Monopodial and sympodial bamboos grown in tropic and sub-tropic countries

Hamid, N. H., Jawaid, M., Abdullah, U. H., and Alomar, T. S. (2023). “Monopodial and sympodial bamboos grown in tropic and sub-tropic countries – A Review,” BioResources 18(3), 6499-6560.

Abstract

Bamboo belongs to the grass family and is an important non-timber forest product in tropic and sub-tropic countries. The global trade of bamboo products is worth billions of dollars and is mainly dominant with monopodial bamboo grown in sub-tropic countries such as China and Japan. Many researchers globally discuss that in addition to species and region, bamboo quality can differ based on its rhizome types because the physiology is different for both monopodial and sympodial bamboo. However, there is a massive competition within the yearly forest products due to the challenges posed by underground root system in agroforestry. This review studied the properties of bamboo with regards to their differences in terms of monopodial and sympodial types of rhizomes. It was found that most of the structural, chemical organic, and mechanical properties are higher in monopodial bamboo, but there is a greater fibre morphology and decay resistance in the sympodial bamboo.

Download PDF

Full Article

Monopodial and Sympodial Bamboos Grown in Tropic and Sub-tropic Countries – A Review

Norul Hisham Hamid,^a,b Mohammad Jawaid,^b,* Ummi Hani Abdullah,^a,b and Taghrid S. Alomar ^c

DOI: 10.15376/biores.18.3.Hamid

Keywords: Bamboo; Rhizome; Growth; Anatomy; Physical; Mechanical properties; Chemical properties; Decay resistance

Contact information: a: Faculty of Forestry and Environment Universiti Putra Malaysia 43400 UPM Serdang, Selangor, Malaysia; b: Institute of Tropical Forestry and Forest Products Universiti Putra Malaysia 43400 UPM Serdang, Selangor, Malaysia; c: Department of Chemistry, College of Science, Princess Nourah bint Abdulrahman University, Riyadh 11671, Saudi Arabia; *Corresponding author: h_noroul@upm.edu.my

INTRODUCTION

Bamboo is a monocotyledon plant and is classified as sub-family of Bambosoidea in the family of Graminae. Worldwide, bamboo consists of 119 genera and 1500 species under three main tribes, namely, Arundinarieae (temperate woody bamboo), Bambuseae (tropical woody bamboo), and Olyreae (herbaceous bamboo). They are distributed within the tropic and sub-tropic regions from sea level to the alpine, with the altitude or from 47° S° to 50° 30’ N and latitude from sea level to 4300 m (Clark et al. 2015). Bamboo stands exist in all continents except for Europe and Antarctica (Ram et al. 2010; Hagarth and Belcher 2013; Mera and Xu 2014).

Bamboo culms cover about 3.2% (37 million hectares) of the world forest area. Approximately 80% of the bamboo stand and species are distributed in the Asia and pacific regions (Mera and Xu 2014). China owns the largest bamboo forest area (601,000 km²) followed by India (108,630) and Myammar (8950 km²) (Fei et al. 2016). The deforestation that occurs in these countries is relieved by the emergence of bamboo forests and in turn this balances the ecosystem.

A bamboo forest is part of the forest ecosystem, and it acts as an important source of carbon and carbon sink (Li et al. 2003). Bamboo possesses a great advantage of reducing global warming by utilizing the carbon dioxide emission produced from modern vehicles, industries, and population growth. One hectare of bamboo culms is able to absorb more than twelve tons of carbon dioxide per year (Raka et al. 2011), while the dicotyledon trees only absorb slightly lower carbon dioxide, ranging from 1.1 to 9.5 tons per year (Chasan 2019). This is due to the fact that bamboo achieves its maximum growth within a one year and matures within 3 to 4 years for sympodoal bamboo and 7 to 8 years for monopodial bamboo (Razak et al. 2010; Fangchun 2001a,b). Depending on the bamboo culm, the photosynthesis process that produces carbohydrates for the growth and maturation is also involved in nutrient uptake from soils.

The bamboo culm grows toward maturation, and when it gets old, it loses its ability to uptake nutrients from soil. The amount of nutrients or inorganic contents in Gigantochloa scortechinii culm declines from a young age (6 months), toward its old age of 6.5 years (Norul Hisham et al. 2006). The oldest bamboo culm experiences an insufficiency in nutrients and will produce flowers and then die if it is not being utilised for any purpose. Therefore, mature bamboo culm needs to be harvested to allow a new shoot to emerge from the rhizome to produce a new culm. The age-maturation of bamboo culm is important to determine the harvesting cycle of each bamboo culm for production, propagation, and its overall sustainability for further utilization. The making of a specific bamboo product depends on the culm age for its maximum quality. Bamboo shoot as a food is best when it emerges less than 3 weeks from soils (Fangchun 2001b). The quality of bamboo higo products, such as barbeque and chop sticks, are maximum for the bamboo culm aged 1 to 2 years (Hamdan and Mohmod 1992). While the most suitable age for bamboo timber and flooring ranges from 3 to 4 years for sympodial bamboo to achieve its maximum strength (Sattar et al. 1994; Mohmod and Phang 2001; Banik 2015).

A mature bamboo culm as a biological material for human products evolved from traditional to a modern application parallel to human civilization. Historical records show that bamboo was used as fire work and in rockets during the Chinese dynasties (Deluca 2016). Indigenus people in Southeast Asia used bamboo as a rice cooker and in weapons in their daily life. Fei et al. (2016) mentioned that half of the world population utilizes bamboo products such as in housing, biocomposites, mats, chopsticks, charcoal, activated carbon, pulp, shoot, and other applications.

Medicine is another category of a small amount of bamboo products. The Pleioblastus amarus leaves can remedy fever, fidgeting, and lung inflammation (Kiruba et al. 2007). The extracts of Sasa senanensis, Bambusa caulis, and Pseudosasa japonica have anti-cancer activity (Panee 2009; Seki et al. 2010; Kim et al. 2013). In addition, bamboo is reported to have great potential for soil erosion control, water conservation, land rehabilitation, and carbon sequestration (Zhou et al. 2005).

The bamboo industry has evolved from being used as basic tools for domestic requirement to world commodities for international markets. The global bamboo market was about USD 68.8 billion in 2018 (Market Research Report 2019). The most popular product, woven bamboo, represents the largest proportion of global exports, estimated at USD 380 million in 2017 (Inbar 2020). China with the largest bamboo forest area is a main exporter for bamboo products. China’s bamboo industry success is not only related to its culture that has been ever expanding, but the proper selection of bamboo species for a specific product for optimum qualities is the main contribution for success. Norul Hisham et al. (2006) explained that there are thousands of bamboo species worldwide and their properties differ by species, age, location, and other external factors. According to the phenotype, bamboo can be divided into three types of rhizomes, namely monopodial (leptomorph), sympodial (pachymorph), and amphipodial. The different rhizome structure possibly influences its growth, development, and maturation (Fangchun 2001a; Fei et al. 2016).

Despite being in the same tribe, the growth and development phases in monopodial and sympodial bamboo culms may be different due to different rhizome structures. Zhao et al. (2014) made comparison between the micro Ribonuleic acid (mRNA) of monopodial bamboo (Phyllostachys pubescens) and sympodial bamboo (Dendrocalamus latiflorus). In their reports, the rhizome of monopodial bamboo can spread laterally while grown in soil, and can also be separated from the mother plant, while sympodial bamboo grows in clusters within a relatively small range. The result indicates that there are 19,295,759 and 11,513,888 raw sequence reads, in which 92 and 69 conserve miRNAs, as well as 95 and 62 novel miRNAs are identified in P. pubescens and D. latiflorus, respectively. The ratio of high conserved miRNA families in D. latiflorus is more than that in P. pubescens. In addition, a total of 49 and 106 potential targets are predicted in P. pubescens and D. latiflorus, respectively, in which several targets for novel miRNAs are transcription factors that play important roles in plant development. Experiments show that miR397, miR1432, and miR7748 are specifically conserved in the leaf sample of P. pubescens.

Taken together, the comparison between P. pubescens and D. latiflorus indicate that monopodial and sympodial bamboo may share different miRNAs and target genes to have a better adaption for their development in different stages, and stress response in their diverse course of evolution. Therefore, monopodial bamboo requires more self-regulation to adapt to the environment than sympodial bamboo, which might be consistent with the generation of lower conserved miRNAs families. Fangchun (2001a) investigated the physical properties of 96 bamboo species and the mechanical properties of 65 bamboo species from both monopodial and sympodial bamboo. The moisture content, density, shrinkage, tensile, and compression properties vary by species, which originated from different rhizome type. The growth, development, and properties of some bamboo species either from monopodial and sympodial rhizomes may also be influenced by the site condition and climate of a specific area.

The International Network for Bamboo and Rattan (INBAR) proposed priority species of bamboo and rattan that include 20 taxa (species and genera) of particular economic importance and another important 18 taxa (Rao et al. 1998). In this context, the priority is based on its specific uses, and the main criteria for the classification of species-usage is general characteristics, such as diameter, wall thickness, internode length, and overall culm height. The priority species by the culm physical properties, P. pubescens, is categorized as medium to large monopodial bamboo with 10 to 20 m height, 18 to 20 cm diameter, internodes up to 45 cm long, and thick wall up to 2 cm (Rao et al. 1998). The P. pubescens is the most successful bamboo species in China for manufacturing glue-laminated timber flooring.

A similar characteristic in sympodial bamboo such as Dendrocalamus asper with up to 20 to 30 m height, internodes 20 to 45 cm long, diameter of 8 to 20 cm, and thick walls up to 2 cm, is that they are only used as furniture, musical instruments, chopsticks, household utensils, and handicrafts (Rao et al. 1998). The thick wall of D. asper does not give advantage for manufacturing glue-laminated board or flooring in Asian countries. The examples of end products from monopodial and sympodial bamboo species are shown in Table 1 and 2.

Table 1. Example of the Utilization of Monopodial and Sympodial Bamboo in China (Liu et al. 2018)

Table 2. Example of the Utilization of Sympodial Bamboo in Malaysia

Another example is the trial of glue laminated bamboo board and flooring from sympodial bamboo G. scortechinii in Peninsular Malaysia during 1998 to 2001. The G. scortechinii culm has an internode ranging 32 to 50 cm long, 11 to 18 cm in diameter, and 6 to 9 mm in wall thickness (Norul Hisham et al. 2006), which is similar to P. pubescens grown in China. However, after two decades of trial, the quality appearance and marker acceptance of laminated bamboo flooring from G. scortechinii was not comparable to P. pubescens. In the period of 1998 to 2015, two laminated bamboo board factories in Malaysia were closed down due to lack of quality appearance for the local market. Another contributing factor is unsustainability of the material, as most of the stock is obtained in the natural forest and the bamboo plantation is not established at the beginning. This indicates that the quality of laminated bamboo flooring and other biocomposites is not only dependent on the basic and physical characteristics. Other properties, such as chemical, mechanical, machining, and appearance that vary between monopodial and sympodial bamboos, are a collective factor for optimum quality. In view of the above, this review aims to elaborate the properties characterization in monopodial and sympodial bamboos.

RHIZOME

The monopodial rhizome has a long and slender culm with a cylindrical or sub-cylindrical form. Its diameter usually is less than that of the culm coming from it (Fig. 1).

Its internode is longer, relatively uniform in length, rarely solid, typically hollow with interruptions at each node by a diaphragm; nodes in some genera usually elevated or inflated, in others no lateral buds in the dormant state are boat-shaped (McClure 1966). The monopodial bamboo is characterized as having strong frost resistance and is distributed in area of higher latitudes, such as Japan, Korea, Yellow River, and Yangtze Valley where there is a slight winter (Fangchun 2001a).

The sympodial rhizome has 6 to 7 large lateral buds on either side of the thick rhizome proper, and the buds grow up to new bamboos with a short rhizome neck (Fig. 1). The rhizome internodes are broader, long, solid, and asymmetrical, while the nodes are not elevated. The underground rhizome consists typically of two parts: the rhizome proper and the rhizome neck. The neck is basal to the rhizome proper, generally shorter in length and obconical in shape. It connects the new rhizome to the mother rhizome. Rhizomes are usually more or less curve-shaped and rarely straight, with maximum thickness, typically somewhat greater than that of the culm (Liese and Kohl 2015).

Being morphologically different, the monopodial bamboo rhizome can be extended horizontally under the soils depending on the species, and its length ranges from 50 to 70 m for P. heteroxyxla, 90 to 250 m for P. viridis, and 200 to 350 m for P. niagra (Jinghua 2000). Sympodial bamboo rhizome, such as B. tulda, can only be extended under the soils, up to 5.2 m (White and Childers 1945). Due to this capability, monopodial and sympodial bamboo rhizomes are commonly referred to as running and clumping bamboos, respectively. Amphipodial, which is a combination of monopodial and sympodial rhizomes, belongs to the genera including Bashania and Shibataea (Maoyi 2007). These genera originated from Japan.

Fig. 1. Monopodial bamboo and rhizome and sympodial bamboo and rhizome (Redrawn with inspiration from Banik et al. 2015)

SPROUT AND GROWTH

Monopodial Bamboo

The P. nigra var. henosis has the shortest sprouting phase (19 days), followed by P. nidularia (20 days), and P. makinio (25 days) as shown in Table 2. The P. heteroclade has the longest sprouting phase (45 days) among the Phyllostachys genera. The sprouting phase of P. pubescence grown in China (28 days) is quicker than those grown in the USA (44 days). This is reflected by the different site and climate between these countries. The growth phase is quickest for P. nigra (24 days) followed by P. pubescens (31 days) and P. makinoi (32 days) in China (Hwang and Ma 1994; Zhang et al. 1997; Li et al. 2005).

Sympodial Bamboo

The Fargesia spathecea has the earliest sprouting phase (59 days) amongst the sympodial bamboo, followed by F. robusta (80 days) and F. denudate (90 days). D. latiflorus has the longest sprouting phase (180 days) amongst the sympodial bamboo. The growth phase is the quickest for Fargesia robusta (70 days) followed by Dendrocalamopsis oldhani (80 days) and D. latiflorus (90 days) in China (Zhou 1999; Qin et al. 1993; Gao et al. 2000).

Overall

The sprouting and growth phases are significantly shorter in monopodial bamboo (32.7 and 33.2 days) compared to the sympodial bamboo (105.8 and 102.6 days), respectively, from further analysis of the statistical data (Table 3). The bamboo shoot elongation rate within 24 h depends on the genera, species and rhizome. P. reticulate records the fastest growth rate (maximum 120 cm/day) for monopodial bamboo (Ueda 1960), and the rate is same as D. asper for sympodial bamboo (Subsansenee 1994). The growth rate of B. balcooa, D. gigantus, and B. vulgaris are recorded as 77 cm/day, 58 cm/day, and 44 cm/day, respectively (Osmastos 1918; Banik 1993).

Table 3. Sprouting and Growth Phases of Monopodial and Sympodial Bamboos

Mono – monopodial, Sym – sympodial, S.E – South east, N – North, S.W – South west, C- central, W – West, E- East, S – South

Table 4. Statistical Analysis of Sprouting and Growth Phases for Monopodial and Sympodial Bamboos

*** Significant at P < 0.01. The value in the parenthesis is standard deviation.

CULM DIAMETER AND HEIGHT

Most bamboo culm achieves maximum height within one year, without showing any further growth for subsequent years (Liese 1985). The classification of culm diameter and height is useful in helping to identify the growth factors for individual species in different site location, topography, climate, and other conditions (Fangchun 2001a). It is also commonly used to classify bamboo according to its suitable usage (Benton 2015; Liese and Kohl 2015). Fangchun (2001a) classified the bamboo growth according to the average diameter namely: Class 1 (diameter more than 12 cm), Class 2 (10 to 12 cm), Class 3 (8 to 10 cm), Class 4 (6 to 8 cm), and Class 5 (less than 6 cm).

Monopodial Bamboo

The P. nigra var. henonis grown in Central China achieves a maximum height of 400 cm in only 34 days (Li et al. 2005). The culm diameter and height vary with genera and species in different site locations (Table 4). The P. makinoi grown in the Dasi site, West Taiwan records the highest diameter at breast height (DBH), height, and point density (5.9 cm, 11.1 m, and 18767 culm/ha) compared to Jhudong site, West Taiwan (4.7 cm, 10.7 m, and 17567 culm/ha), respectively. The P. pubescence is grown in the Shi Zhua site, Taiwan with a lower temperature (11.5 °C), and higher elevation that has a significantly higher DBH, height, and culm density (10.6 cm, 21.4 m, and 8344 culm/ha) compared to the Hui sun site (6.8 cm, 10.3 m, and 7933 culm/ha), which has temperature and elevation of 20.3 °C and 667 m, respectively (Wang and Chen 2015). This indicates that the P. pubescens prefers the mountain climate with elevation of 1000 to 1500 m.

The majority of the monopodial bamboo (Table 5) species is classified as class 4 and 5, with exception of P. pubescens (Class 2). Physically, P. pubescens is selected for manufacturing laminated flooring and other composite board in China. The quantity of bamboo strips is proportional to the culm diameter. The P. pubescens records the longest culm (21.4 m) for monopodial bamboo. Other monopodial bamboo species produce a culm length less than 12 m (Table 4).

Sympodial Bamboo

Clump size also influences the culm DBH and height as in sympodial bamboo. Generally, the culm’s DBH and height increases with increasing clump size (Table 5). The small (4.5 m²), medium (7.13 m²), and large (9.3 m²) clump sizes of B. stenostachya produce the DBH (8.7 cm, 9.3 cm and 10.2 cm) and height (15.3 m, 17.4 m, and 20.3 m) respectively (Chen et al. 2012). The sympodial bamboos have all the classes as shown in Table 5. The species with diameter class 1 including D. asper, D. latiflorus, G. levis, Melocanna bambusoides, and Oxytenanthera abyssinica. Others, including B. vulgaris var. striata, B. stenostachya, Gigantochloa scortechinii, G. wrayi, and S. grande are classified as class 2, the same as P. pubescens. The D. latiflorus and T. oliveri are recorded as the longest culm (25 m) for sympodial bamboo. This is followed by B. vulgaris var. striata, D. asper, and M. bambusoides (23 m), and lastly, by B. stenostachya, G. ligulata, and S. funghomii (20 m).

Overall

The sympodial bamboo (9.3 cm and 17 m) has a significantly higher DBH and height than monopodial bamboo (5.6 cm and 10.8 m), as shown by the statistical analysis of the data (Table 5). This factor may be due to the fact that most sympodial bamboo are grown in tropical countries that are rich in sunlight and rain for photosynthesis. The starch stored in parenchyma is used for the culm growth. By contrast, most monopodial bamboo is grown in temperate countries with less sunlight, and the starch are stored in the parenchyma that are later used for their sustenance during winter and snow.

Table 5. DBH and Maximum Height of Monopodial and Sympodial Bamboo

Table 6. Statistical Analysis of Basic Characteristics of Monopodial and Sympodial Bamboos

*Significant at P < 0.1

The application of NPK (the proportion of three plant nutrients in order: nitrogen (N), phosphorus (P) and potassium (K)) fertilizer of 0.75 to 0.93 kg/clump at 2 or 3 times per year could increase the bamboo production for Neosinocalamus affinis (Long and Jiang 1996). The G. levis clump applied with 12 kg chicken manure gives the highest shoot sprouting. The fertilization using cow dung, chicken manure, and rusk husk ash at 0.5, 1, and 2 kg per clump during growth and development in G. leavis and D. asper were only important at the first year of plantation establishment (Fernandez et al. 2003). The average DBH of P. pubescens clump aged more than one year fertilized with N:P:K (244 kg N ha/year, 196 kg P/ha, 196 kg K ha/year) for 30 years is identical with the unfertilized clump (10.1 cm). This shows that the bamboo achieves its maximum growth in one year, as mentioned by Liese (1985) and Banik (2015).

ANATOMY

Microstructure

In the transverse section, the microstructure of monopodial and sympodial bamboo is the same as they are both covered by epidermis, hypodermis, and cortex in the outermost zone. The epidermis consists of axially elongated cells, shorter cork, silica cells, and stomata. The epidermis cells are always covered on the outside by a cutinized layer of cellulose and pectin with tangential lamellation. Its main function is for water blockage and tissue protection. The hypodermis is the next layer, and it consists of several layers of thick-walled scerenchymatous cells. This is followed by the pith ring or pith periphery, in which a non-vascular tissue is composed of layers of parenchyma cells, and often heavily thickened and lignified. They are commonly long in tangential direction, but small in radial and longitudinal directions. The ground tissue is next to the pith ring. The ground tissue contains parenchyma cells with embedded vascular bundle (Grosser and Liese 1971).

Table 7. Vascular Bundle Type Classification by Grosser and Liese (1971, 1973)

The thin walls of parenchyma cells are connected to each other by numerous simple pits. The cell is thinner than the fibre wall, and they are located mainly on the longitudinal walls, while the horizontal walls are scarcely pitted. The parenchyma tissue is lignified during the sprouting of the culm and the cells may store a certain amount of starch. A small and elongated parenchyma cell, like a cubic cell, appear and are interspersed between the long cells. The cubic-like cell is characterized with a denser cytoplasm and thin walls, it is not lignified even in mature culm (Grosser and Liese 1971).

Vascular Bundle

The bamboo vascular bundle consists of two metaxylem vessels, phloem, and protoxylem attached to the fibre bundle. The size and shape vary with genera and species, as well as along the internode height and across the culm wall in transverse direction. The classification of vascular bundle was slightly different between European and Chinese researchers. Grosser and Liese (1971, 1973) on their detailed analysis of 52 species in 14 genera classified the vascular bundle to four different classes as shown in Table 7.

Types I, II, III, and IV of the vascular bundles obtained from sympodial bamboo are reported by researchers (Suzuki and Itoh 2001; Sharma et al. 2017; Nordahlia et al. 2019). In contrast to the vascular bundle classified by Grosser and Liese (1971), Xin and Qion (1983) classified vascular bundles into four different classes using 10 genera and 45 species belonging to monopodial bamboo natively from China (Table 8).

Table 8. Classification of Vascular Bundle Type According to Xin and Qion (1983)

Vascular bundle classification made by Grosser and Liese (1971) is mostly used and referred to by many researchers worldwide. In an anatomical structure point of view, the sympodial bamboo has more fibre strands or island at the bottom (Type III), and both bottom and top (Type IV) of vascular bundle. This generally gives additional support and strength to the culm. The monopodial bamboo is structured by only a central vascular bundle (Type I) and surrounded with sclerenchyma sheaths. Therefore, the monopodial bamboo, such as P. pubescens, is more pliable and softer, which is advantageous during processing such as cutting, splitting, moulding, and sanding. The type of vascular bundle may be the same or differ within the individual culm of each species. In monopodial bamboo, the S. manii grown in India has vascular bundle Type I, as classified by Grosser and Liese (1971), along its culm height (Naithani et al. 2010). In contrast, Sharma et al. (2017) found a Type III vascular bundle at the basal and middle portions, while the Type II of vascular bundle was at the top portion of S. manii. The P. pubescens, P. nigra, and P. bambusoides grown in South Korea have vascular bundle Type 1 with tylosoid in the intercellular space (Jeon et al. 2018).

Monopodial Bamboo

The vascular bundle dimension and shape vary with genera, species, site location, culm height, and diameter in transverse section (Mohamed et al. 2019). In monopodial bamboo (Table 9), the vascular bundle frequency differs across the transverse and longitudinal directions. The frequency of vascular bundle in 12 China bamboo species is biggest at the outer zone (14/mm²), followed by the middle zone (4.8/mm²), and smallest at the inner zone (2.9/mm²). The frequency is also increased with the internode height in P. pubescens (Fangchun 2001a). The frequency of vascular bundle is highest in order of Arundinaria japonica (7/mm²), Brachystachyum densiflorum (7/mm²), and Indocalamus mingoi (6.67/ mm²).

Sympodial Bamboo

In sympodial bamboo, the S. pergracile has Type II vascular bundle along the culm height (Sharma et al. 2017). The B. rigida grown in Sichuan, China has vascular bundle Type III at the middle zone of the transverse direction, while Type I and II are located at inner and outer zone, respectively (Huang et al. 2015). In the transverse direction, the D. brandisii grown in China has vascular bundle Type II, Type III, and Type V at the periphery, middle, and outer zones, respectively (Wang et al. 2016). The vascular bundle of bamboo grown in Malaysia is dominated with Type II, III, and IV. The species with Type II includes S. brachycladum and S. zollingeri. The Type III includes G. thoii, G. scortechinii, G. ligulata, G. wrayi, G. brang, S. grande, B. heterostachyum, and B. vulgaris cv. vittata. Type IV includes B. vulgaris, B. blumeana, and D. asper. In all cases, the vascular bundle Type IV is mostly classified as a thick-walled and large-diameter bamboo species (Nordahlia et al. 2019). This indicates that the vascular bundle type may be similar to or different from each of the individual culm of the same species.

The vascular bundle dimension for radial/tangential (R/T) in sympodial bamboo, G. scortechinii increases from the inner zone to the outer zone, and it significantly differed at the middle portion with age. A smaller vascular bundle tends to be denser than a bigger one (Norul Hisham et al. 2006). The R/T ratio of vascular bundle increases from inner zone toward the outer zone in basal, middle, and top portion of B. rigida aged 1, 3, and 5 years. Overall, the R/T ratio of vascular bundle is not significantly different with culm height for all ages (Huang et al. 2015). The radial length and tangential diameter of vascular bundle in G. scortechinii is longer at the nodal portion compared to the internode portion (Table 10). In the internode, the vascular bundle is longest in descending order of G. levis (1171.14 µm), G. scortechinii (787.2 µm), and G. wrayi (754.1 µm). In the node, the vascular bundle length in descending order is G. levis (1193.2 µm), G. scortechinii (1078.2 µm), and G. wrayi (963.4 µm). In the internode, the vascular bundle width is highest in G. levis (798.3 µm), followed by G. scortechini (544.6 µm), and G. wrayi (532.9 µm). In the node, the vascular bundle width in descending order is G. levis (720.4 µm), G. scortechinii (587.9 µm), and G. wrayi (685.8 µm) (Mohd Tamizi et al. 2011).

The metaxylem vessel diameter increases from the outer zone toward the inner zone in all age classes of G. scortechiii (0.5, 1.5. 3.5, 5.5, and 6.5 years) (Table 11). Vessel diameter is significantly bigger with age at the outer and inner zones, but this is not the same at the middle zone. The diameter gradually increased from the youngest age of 0.5 years (0.51 µm) to a maximum diameter at the age of 5.5 years (0.62 µm). The vessel diameter in G. scortechinii is also smaller than P. pubescens, which has an average of 0.98 µm (Fangchun 2000a). A smaller metaxylem vessel diameter is reported in D. brandisii (Wang et al. 2016), where it slightly increases with age from 139.4 µm (aged 1 year) to 162.0 µm (aged 3 years). The metaxylem vessel is slightly elliptical in B. rigida due to the radial length is longer than the tangential diameter (Table 9). The metaxylem vessel diameter is not significantly different with age but it tends to be slightly smaller from the basal portion toward the top. The diameter also significantly increases from outer part of the vessel towards the inner in all ages. The metaxylem diameter ranges from 112.3 μm to 127.4 μm, 97.8 μm to 127.5 μm, and 104.6 μm to 129.2 μm for bamboo aged 1, 3, and 5 years, respectively (Huang et al. 2015). Liu et al. (1998) mentioned that larger vessel diameter in laminated bamboo of D. latifflorus could probably cause its lower glue bond strength compared to P. edulis.

Table 9. Vascular Bundle Frequency in Monopodial and Sympodial Bamboos

Table 10. Radial Length, Tangential Diameter, and R/T Ratio of Vascular Bundle in Monopodial and Sympodial Bamboos

Overall Features

The radial length and tangential diameter of the vascular bundle is significantly higher in monopodial bamboo (0.39 μm and 0.37 μm) than sympodial bamboo (0.28 μm and 0.22 μm), respectively, as shown in the statistical reanalysis results (Table 12). While the R/T ratio of vascular bundle is significantly higher in sympodial bamboo (1.23) than the monopodial bamboo (1.07), the metaxylem vessel diameter is significantly higher in sympodial (127.97 μm) than the monopodial bamboo (72.38 μm). In contrast, the vascular bundle frequency is significantly higher in monopodial (5.18/mm²) than the sympodial bamboo (2.80/mm²).

Table 11. Metaxylem Vessel Diameter in Monopodial and Sympodial Bamboos

Table 12. Statistical Reanalysis of the Vascular Bundle Elements in Monopodial and Sympodial bamboos

DF– Degree of freedom, F– F ratio, NS is not significant at P > 0.1, * is significant at P < 0.1, ** is significant at P < 0.05. The value in parentheses is standard deviation.

The proportion of metaxylem vessel diameter is significantly higher in sympodial (6.40%) than the monopodial bamboo (5.21%), but not for fibre and parenchyma proportions. The proportion of fibre and parenchyma are not significantly different for monopodial (40.92% and 45.56%) and sympodial (53.00% and 53.38%) bamboos, respectively.

Fibre Morphology

Monopodial bamboo

In monopodial bamboo (Table 13), I. migoi and P. pubescens growing in China have the longest fibre (2250 μm), while the Indocalamus tessellatus grown in China has the shortest fibre (1435 μm). The Brachycladum densiflorus grown in China records the widest fibre (16.9 μm), while the Arundinaria amabilis also grown in China has the thickest fibre wall, and the P. viridis grown in USA has the widest fibre lumen (5.63 μm). The fibre of the three monopodial bamboos grown in Taiwan is the longest, when ranked in descending order of Phyllostachys bambusoides (2033 to 2239 μm), P. nigra (1934 to 2199 μm), and P. pubescens (1375 to 1573 μm). The outer zone has a longer fibre than the inner zone for all species (Jeon et al. 2018).

Table 13. Fibre Morphology in Monopodial and Sympodial Bamboos

FL: Fibre length; FD: fibre diameter; FLD: fibre lumen diameter; FWT: fibre wall thickness

Sympodial bamboo

In sympodial bamboo (Table 14), the longest and shortest fibres are recorded for G. scortecinii (4240 μm) grown in Malaysia and B. basihirsuta (1667 μm) grown in China, respectively. The fibre is widest in B. heterostachya (26.8 μm) grown in Malaysia and narrowest in D. striticus (9.9 μm) grown in China. The fibre wall is thickest in G. thoii (12.2 μm) grown in Malaysia and thinnest in D. gigantus (1 μm) grown in Thailand. The fibre lumen is largest in B. blumeana (10 m) grown in Malaysia and smallest in Sinarundina chungi (1.59 μm) grown in China. The fibre wall diameter, thickness, and lumen diameter of B. blumena, B. vulgaris, and G. scortechinii are not significantly different with culm aged one to three years. The fibre length ranges from 1.89 μm to 1.99 μm in B. blumeana, from 3.30 μm to 3.76 μm in B. vulgaris, and from 3.50 μm to 4.24 μm in G. scortechinii. The fibre diameter ranges from 0.018 μm to 0.02 μm in B. blumeana, 0.017 μm in B. vulgaris and G. scortechinii. The fibre wall thickness is 0.05 in B. blumeana, ranges from 0.06 to 0.07 in B. vulgaris, and 0.07 to 0.08 in G. scortechinii. The fibre lumen diameter ranges from 0.009 to 0.010 in B. blumana, from 0.002 to 0.003 in B. vulgaris, and G. scortechinii (Mohmod et al. 1990).

In the G. scortechinii aged 0.5 to 6.5 years grown in the same clump, the youngest culm aged 0.5 years had the shortest fibre (2.23 μm). Culm aged 1.5 years had the longest fibre, but the fibre tends to be shorter with ageing. The fibre diameter does not differ by age, and the mean is 26 μm. The widest fibre lumen diameter is recorded in the youngest culm aged 0.5 years (10 μm) and the diameter remains unchanged beyond age 1.5 years. The fibre wall is thinner at the early age of 0.5 years (8 μm) but thickens as much as 1 μm at age of 1.5 years (Norul Hisham et al. 2006). The fibre length is significantly higher for the internode than the node with an average of 2074.2 μm and 1672.6 μm in G. brang, G. levis, G. scortechinii, and G. wrayi. The fibre is longest in the middle section (2064.4 μm), followed by the inner (1861.4 μm) and outer (1698.5 μm) for the above three species. The fibre is wider in the node (22.0 μm) than the internode (18.2 μm). It is the widest in descending order of G. brang (22.8 μm), G. levis (22.7 μm), G. wrayi (17.9 μm), and G. scortechinii (17.3 μm), respectively. The fibre is also widest at the middle section (22.4 μm), followed by the inner (19.6 μm) and outer sections (18.5 um) across the culm wall.

The fibre lumen is widest in descending order of G. scortechinii (8.60 um), G. brang (4.75 um), G. levis (4.75 um), and G. wrayi (4.75 um). The lumen is also larger in node compared to the internode. The lumen diameter is largest at the inner section (5.96 um) and smaller toward the outer section (5.44 um). The fibre wall is thickest in descending order of G. levis (9.34 μm), G. brang (9.02 μm), G. wrayi (7.02 μm), and G. scortechinii (4.30 μm). The node has a thicker fibre wall than the internode. The fibre wall is also thickest in the middle zone (8.43 μm) followed by the outer (7.03 μm) and inner (6.80 μm) zones (Mohd Tamizi et al. 2011). The fibre length in Schizostachyum manii, Scizostachyum munroi, and Schizostachyum pergracile grown in India increased from the inner zone and reached a maximum at the middle zone but further decreased toward the inner zone in the transverse section of all culm height. The fibre characteristics, such as diameter, lumen diameter, and wall thickness decreased along the culm height (Sharma et al. 2017). Amongst the 4-year-old G. scortechinii, G. thoii, G. ligulate, G. wrayi, G. brang, S. brachycladum, S. grande, S. zollingeri, B. vulgaris, B. blumeana, B. heterostachya, B. vulgaris cv Vittata, and D. asper grown in Malaysia, G. thoii has the longest fibre (4070 μm) and the fibre length for all species are ranged from 2330 μm to 4070 μm (Norhadlia et al. 2019).

Table 14. Statistical Reanalysis of the Fibre Morphology in Monopodial and Sympodial Bamboos

DF– Degree of freedom, F– F ratio, NS is not significant at P > 0.1, *** is significant at P < 0.01. The value in parentheses is standard deviation

The statistical reanalysis of the fibre morphology data shows that the fibre length and diameter are significantly longer and wider in sympodial bamboo (2494.8 μm and 17.06 μm) than the monopodial bamboo (1929.7 μm and 12.95 μm), respectively. In contrast, fibre lumen diameter and wall thickness are not significantly different in monopodial (3.63 μm and 3.93 μm) and sympodial (4.49 μm and 4.39 μm) bamboos, respectively.

PHYSICAL PROPERTIES

Basic Density and Volumetric Swelling

The density is closely related to the mechanical properties of bamboo and it differs by species, age, culm height, and portion. The density increases from the basal portion towards the top as well as from inner to the outer culm wall. The main reason for this trend is that the top and outer portion are heavily distributed by vascular bundles and a thinner vessel diameter.

Monopodial Bamboo

The density progressively increases with age as occurs in P. pubescens and S. affinis aged 1 (0.43 g/cm³ to 0.49 g/cm³) to 7 years (0.62 g/cm³ and 0.63 g/cm³), respectively, but it tends to decrease beyond 8 years (Table 16). The density is higher for bamboo grown in drought and low temperature areas, as it has compact tissue. In contrast, the bamboo density is lower in warm, moist climates and nourishing soil because its thick culm wall tissue is loose (Fangchun 2001a).

The same trend occurs for N. affinis grown in China, for which the density significantly increases with age for 1 year (0.56 g/m³), 2 years (0.68 g/m³), and 3 years (0.77 g/m³). However, all bamboo age classes fertilized with potassium, calcium, and nitrogen show a lower density than the unfertilized bamboo especially with a higher dose of nitrogen (Xie et al. 2019). These results are in a good agreement with the findings of Yang et al. (2014), in which the long-term nitrogen fertilization significantly decreased the basic density of P. pubescens. The density increases from basal portion (0.60 g/m³) toward the middle (0.69 g/m³) and top (0.79 g/m³) portions of B. vulgaris aged 4 years grown in China (Huang et al. 2014). The volumetric swelling is highest and lowest in B. sinospinosa (32.8%) and P. glauca F. Youzhu (7.4%).

Sympodial Bamboo

The density decreases with age for 1-year (1.10 g/m³), 2-years (1.04 g/m³), and 3-years-old (1.00 g/m³) wild B. blumeana culms. In contrast, the density increases with ages in 1-year (0.29 g/m³), 2-years (0.51 g/m³), and 3-years-old (0.54 g/m³) wild B. vulgaris var. striata. The same trend occurs in wild G. scortechinii, where the density increases with age in 1-year (0.47 g/m³), 2-years (0.53 g/m³), and 3-years-old (0.56 g/m³) culms. Overall, B. blumeana has the highest density follow by G. scortechinii and, lastly B. vulgaris (Abdul Latif et al. 1990). The density of wild G. scortechinii grown in the same clump also increased with age for 0.5 (0.53 g/m³), 1.5 (0.59 g/m³), 3.5 (0.61 g/m³), 5.5 (0.63 g/m³), and 6.5 years (0.68 g/m³). Along the internode height, the density trends are also slightly increased from the bottom portion toward the top portion along the sixth internode, for all age classes ( Norul Hisham et al. 2003; Norul Hisham et al. 2006).

The densities of 4-year-old Malaysian bamboo, as reported by Nordahlia et al. (2019) in descending order, are G. thoii (0.75 g/m³), G. scortechinii (0.64 g/m³), G. wrayii (0.63 g/m³), S. grande (0.63 g/m³), B. vulgaris (0.61 g/m³), S. brachycldum (0.59 g/m³), D. asper (0.56 g/m³), B. vulgaris cv vittata (0.55 g/m³), G. brang (0.54 g/m³), B. heterostachya (0.53 g/m³), B. blumeana (0.48 g/m³), G. ligulata (0.44 g/m³), and S. zollingeri (0.36 g/m³). Within the culm region, the node density is not significantly different from internode density either at basal or top portions for D. asper grown in Thailand. The density at basal portion of culm without node (0.71 g/m³) is not significantly different from the one with node (0.69 g/m³). The density at the top portion of culm without node (0.90 g/m³) is not significantly different from the one with node (0.92 g/m³). The same trend is reported for P. bambisoides (monopodial type) by Tomak et al. (2012) as well as for Guadua angustifolia (sympodial type) by De Vos (2010).

Overall Analysis

The statistical reanalysis of the density in monopodial and sympodial bamboos shows that there is no significant different of density (0.58 g/cm³ and 0.59 g/cm³) for both types of bamboo. In contrast, the volumetric shrinkage is significantly higher for sympodial (16.92%) than the monopodial (12.63%) bamboos.

Table 15. Basic Density and Shrinkage Properties of Monopodial and Sympodial Bamboo

Table 16. Basic Density and Volumetric Shrinkage of Monopodial and Sympodial Bamboos

DF– Degree of freedom, F– F ratio, NS is not significant at P > 0.1, *** is significant at P < 0.0. The value in parentheses is standard deviation

MECHANICAL PROPERTIES

Bamboo has high mechanical and workability properties and is a preferable material for many uses in agricultural, industrial, building, and architecture sectors. The flexural ductility of bamboo (Ph. pubescens) is 3.06 times that of wood (Tectona grandis). The bending MOR of bamboo (P. pubescens) is 1.72 times that of wood (Tectona grandis), while its MOE is 0.84 higher than wood at similar density. High length-to-width ratio, density, and strength of bamboo fibers, as well as their parallel orientation all contributed to the excellent ductility and strength properties of bamboo (Chen et al. 2020). The mechanical properties differ with the bamboo culm position, portion, and section. Generally, it is higher at the upper position than the lower position, and higher at the outer section of the culm wall than the inner section. This gives rise to a denser and larger vascular bundle in the outer section than at the inner section (Fangchun 2001b).

Monopodial Bamboo

The effect of age on the mechanical properties of bamboo is significantly important for choosing an optimum harvesting age, the quality of end products, and service life ( Norul Hisham et al. 2006). The compression and tensile strengths of Ph. pubescence gradually increase from one to five years but are almost constant from six to eight years before slightly declining from nine to ten years. Therefore, it is assumed that the best harvesting age for P. pubescens ranges from six to eight years (Fangchun 2001b). The mechanical properties of bamboo are clearly influenced by the species seen as shown in Table 17. The highest compression, tensile, and modulus of rupture for monopodial bamboo grown in China are P. pubescens (86.5 MPa), P. decora (310.8 MPa) and P. glauca (213.4 MPa).

Sympodial Bamboo

The highest compression, tensile, and modulus of rupture strenghts for sympodial bamboo species grown in China are B. rigida (79.8 MPa), D. latiflorus (199.1 MPa), and B. rigida (196.4 MPa). It is G. scortechinii (59.1 MPa), D. asper (222 MPa) and G. wrayi (201 MPa) for Malaysia bamboo respectively. The B. bambos has a highest tensile (260 MPa) and modulus of rupture (225 MPa) for the Thailand bamboo (Table 17).

In contrast, the lowest compression, tensile and modulus of rupture strengths for sympodial bamboo grown in China is recorded in D. beecheyanis and the values are 19.4 MPa, 92.9 MPa and 40.5 MPa respectively. In Malaysia bamboo, the lowest is B. blumeana (27.1 MPa), D. asper (222 MPa) and B. heterostachya (120 MPa) respectively. The lowest tensile (110 MPa) and modulus of rupture (145 MPa) is recorded in B. longispiculata for Thailand bamboo.

The shear, compression, and static bending strength of B. blumeana, B. vulgaris var. striata and G. scortechinii aged 1, 2 and 3 years are significantly increased with age (Mohmod et al. 1990). Nordahlia et al. (2019) also found that the MoR and MoE of 13 Malaysian bamboos are increased with the culm height and the trend is the same for G. scortechinii (Shahril and Mansur 2009), D. latiflorus, D. meerrillanus, B. vulgaris (Leoncio 2017) and D. strictus (Bhonde et al. 2014). The increment of MoR and MoE along the culm height is accompanied by the higher number of vascular bundles (Nordahlia et al. 2019).

Hamdan et al. (2009) reported that the MoR of bamboo without node is significantly higher at the top (258 MPa) than the basal (140 MPa) portions. The MoR at the top portion (147 MPa) is also significantly higher than at the basal portion (95 MPa) for the bamboo with node. A higher MoR at the internode portion is also contributed to its longitudinal straight cells as compared to the partially interrupt of radial cells at the node region. Bamboo with node fails quickly at the node region itself as compared to bamboo with internode. This trend is the same for sympodial bamboo, Guadua angustifolia (De Vos 2010) and Gigantochloa scortechinii. However, it is contradicted with monopodial bamboo, P. pubescens (Shoa et al. 2010; De Vos 2010), which the MoR is not significantly different in bamboo with and without the node. The MoR of bamboo with node is 32% (basal portion) and 43% (top portion) lower than bamboo without node in D. asper (Srivaro and Jakronod 2016), 20% lower than bamboo without node in G. angustifolia (De Vos 2010) and 27% lower for bamboo without node in G. scortechinii (Hamdan et al. 2009).

There is no significant difference of the MoE for D. asper with or without node (Srivaro and Jakronod 2016), as well as in P. pubescens and G. angustifolia (De Vos 2010); P. bambusoides (Lee et al. 1994; Tomak et al. 2012). The mechanical properties are higher at the top portion in the same or different species due to a higher volume fraction of vascular bundles and density (Amada et al. 1996; Malanit 2009; Dixon and Gibson 2014). The shear strength of D. asper aged 10 years without node are not significantly different for basal (12.3 MPa) and top (14.2 MPa) portions. The same trend occurs for D. asper with node for basal (11.9 MPa) and top (13.1 MPa) portions. The shear strength is higher at the top portion than the lower portion regardless of node or internode as the shear strength is mostly influenced by both density and culm height. This demonstrates that failure occurs by slipping of two shearing planes and a tearing failure of the soft parenchyma ground tissue as a result of the shear force (Srivaro and Jakronod 2016).

In the same study, Srivaro and Jakronod (2016) reported that the tensile strength of D. asper without node is significantly higher at the top (299 MPa) than the basal (165 MPa) portions. The same trend for the D. asper with node for the top (145 MPa) and basal (73 MPa) portions. A higher tensile strength at the internode than the node of the region for all culm heights is also obtained in P. bambusoides and P. pubescens (Lee et al. 1994; Shao et al. 2010). A higher tensile strength at the internode region is due to its longitudinal straight cell as compared to partly radial aligned cells at the node of the region, which is likely a loose compact structure (Wang et al. 2014).

Overall

The monopodial bamboo (207.18 MPa and 160.66 MPa) has a significantly higher tensile and modulus of rupture than the sympodial bamboo (122.27 and 72.63 MPa), respectively, as shown in the statistical reanalysis of the data. However, the compression strength is not significantly different from the rhizome as shown in Table 17.

Table 17. The Compressive, Tensile and Modulus of Rupture for Monopodial and Sympodial Bamboos

Table 18. Statistical Reanalysis of the Compressive, Tensile and Modulus of Rupture in Monopodial and Sympodial Bamboo

DF– is degree of freedom, F– is F ratio, NS is not significant at P > 0.1, *** is significant at P < 0.0. The value in parentheses is the standard deviation.

CHEMICAL PROPERTIES

Bamboo tissue consists of cellulose, hemicellulose, lignin, extractives, ash, silica (as a component of ash), starch, as well as various sugars akin to other monocotyledon and dicotyledon plants. The bamboo cellulose is composed of a longer chain of C₁₂H₁₀O₁₅, and its molecular weight is approximately 1,500,000 g/mol. The cellulose in bamboo can be further separated into 70% to 80% alpha cellulose, 25% beta cellulose, and 1% to 5% gamma cellulose (Fangchun 2001a). The bamboo hemicellulose is mainly composed of pentosane with a small quantity of hexoan. About 90% of bamboo hemicellulose is made from xylan. The bamboo xylan is made up of D-glucuranate arabinoxylan, which comprises 4-oxygen-methyl-D-glucuranate, L-arabinose, and D-xylose. The composition of bamboo arabinoxylan is different from conifers and broad-leaved trees. The polymerized molecules of bamboo xylan are more than that of trees. The content of pentose in bamboo ranges from 19% to 23%, which is close to broad leaves and much higher than that of conifers, which is 10% to 15% (Maoyi et al. 2007).

The structure of hemicellulose is determined by mainly arabinoxylans linked via (1-4)-ß-glycosidic bonds with branches of arabinose and 4-O-methyl-D-glucuronic acid (Lou et al. 2012). The bamboo lignin is a typical herbaceous lignin, consisting of three phenyl propane units, i.e., paradinum, guaiacyl, and mauve in the ratio of 5:34:11. The specific features of bamboo lignin lie in the presence of dehydrogenated polymerides and 5% to 10% of acrylic ester. The lignin content of one-year-old bamboo ranges from 20% to 25%, approaching a broad-leaved wood and some grass (such as wheat straw 22%), and lower than that of conifers. The specific features of bamboo lignin lie in the existence of dehydrogenated polymerides and 5% to 10% of acrylic ester (Maoyi et al. 2007). Information on the content and distribution of lignin at each developmental stage is crucial for the exploitation of bamboo biomass (Chang and Holtzapple 2000; Shimokawa et al. 2009).

The lignin and the process of lignification in bamboo cells are used by researchers to study the earliest growth of bamboo cells toward its maturation. In bamboo, lignification in the culm proceeds acropetally, whereas lignification in each internode proceeds basipetally (Itoh 1990). Fibres and parenchyma cells of bamboo develop thick secondary walls that are composed of polylamellate structures containing broad and narrow lamellae (Parameswaran and Liese 1976; 1980). The deposition of lignin is much denser in the narrow lamella, and the distribution of the lignin-rich layers in bamboo fibres shows concentric rings in cross-sectioned walls (Parameswaran and Liese 1976). The pores of cell walls and cell corners are filled with lignin as seen in rapid-freezing and deep-etching (RFDE) electron microscopy (Nakashima et al. 1997; Fujino and Itoh 1998; Hafrén et al. 1999). In contrast to the findings made by Itoh (1990), the lignification of bamboo cells in various age classes of bamboo P. pubescens still occurred after the first growing season.

The protoxylem vessels are lignified in the early stage of vascular bundle differentiation. Upon completion, metaxylem vessel and fibre walls initiate lignification from the middle lamella and cell corners. Most of the parenchyma cell walls are lignified after the stem reaches its full height, while a few parenchyma cells remain non-lignified even in the mature culm. The cell walls of fibres and most parenchyma cells are further thickened during the stem growth to form polylamellate structure and the lignification process of these cells may last even up to 7 years. The fibre walls are rich in guaiacyl lignin in the early stage of lignification, and lignin rich in syringyl units are deposited in the later stage. Vessel walls mainly contained guaiacyl lignin, while both guaiacyl and syringyl lignin are present in the fibre and parenchyma cell walls (Lin et al. 2002). The unlignified primary wall (ULP) of P. pubescens is characterized by the narrow spacing between the cellulose microfibrils in fibres, but not in parenchyma cells. The unlignified secondary wall (ULS) largely consisted of dense cellulose microfibrils with narrow spacing or “slit-like” pores.

The cell wall architecture of the delignified secondary wall (DLS) in fibres showed porosity similar to that of ULS. Pores in the middle lamella and secondary walls of ULS in fibres are reduced significantly or disappear immediately after lignification. However, the pores reappear following delignification. The deposition of lignin in ULS immediately proceeds in the pores during maturation to LS. The pore sizes of primary and secondary fibre walls are significantly smaller in bamboo than in either Eucalyptus or Pinus, suggesting a denser arrangement of cellulose microfibrils in bamboo fibre walls than in either tree species. The narrow spacing between cellulose microfibrils in bamboo fibres may be one of the reasons for the deposition of less lignin in bamboo than in tree species (Suzuki and Itoh 2001).

In Sinobambusa tootsik (Tsuyama et al. 2017), the content of monolignol glucosides is maximum during the early stages of lignification, whereas the contents of monolignols peak at later stages of lignification. Elongation growth is ended by the culm lignin content, which is approximately half that of mature culms.

Monopodial Bamboo

In relation to species (Table 19), the α-cellulose, hemicellulose, and lignin contents in monopodial bamboo P. heterocycla (Carr.) Mitford cv. Pubescens aged 4 years are 42.7%, 25.52%, and 21.15%, respectively (Wang et al. 2021). The Melocacna baccifera contains 52.78% α-cellulose, 21.1% hemicellulose, 25.2% lignin, 4.13% hot water soluble, 3.24% hot water soluble, 2.45% ash, 19.5% NaOH, and 3.48% ethanol/toluene extractives (Tripathi et al. 2018). In relation to the culm age (Table 20), the holocellulose, lignin, ethanol/toluene extractive of monopodial bamboo P. edulis are not significantly different with age (1, 2, and 3 years) ranging from 65.97% to 67.24%, 30.48% to 32.09%, and 4.59% to 5.11%, respectively. The ash content is significantly lower in the oldest culm (0.89%), and it is not significantly different for culm aged 1 (1.83%) and 2 years (1.68%). In contrast, the silica content is significantly high for the oldest culm (0.30%), while it is not significantly different for culm aged 2 (0.28%) and 3 years (0.21%) (Ju et al. 2021).

In relation to the culm portion (Table 20), the holocellulose, ethanol/toluene, ash, and silica contents in monopodial bamboo P. edulis aged 1, 2, and 3 years are not significantly different with the culm height ranging from 65.77% to 67.69%, 4.58% to 4.85%, 1.36% to 1.72%, and 0.23 to 0.33%, respectively, with the exception of the lignin content. The lignin content is significantly highest at the middle portion of the culm (32.92%), while it is not significantly different at the basal (31.01%) and top portions (30.67%), regardless of age (Zhan et al. 2021).

Sympodial Bamboo

The chemical composition of cultivated sympodial bamboos G. brang, G. levis, G. scortechinii, and G. wrayi varies by species, portion (node or internode), and section (outer, middle, or inner) of the culm (Table 20). The α-cellulose is highest in descending order of G. brang (51.58%), G. scortechinii (46.87%), G. wrayi (37.66%), and G. leavis (33.81%). Regardless of species, the α-cellulose is not significantly different with node (42.74) and internode (42.22), but the outer culm layer has a significantly highest α-cellulose (49.07%), followed by middle (41.28%), and inner (37.09%) layers. The holocellulose is highest in G. wrayi (84.53%) but it is not significantly different from G. levis (84.52%). The G. brang (79.70%) has a significantly higher holocellulose content than the G. scortechinii (74.63%). Overall, the node (81.66%) has a significantly higher holocellulose than the internode (80.03%) and it is significantly in descending order of outer (82.99%), middle (80.89%), and inner (78.65%) layers of the culm wall.

The lignin is significantly highest in G. scortechinii followed by G. wrayi (37.66%), but it is not significantly different for G. brang (24.83%) and G. levis (26.50%). Overall, the lignin content is significantly higher in internode (32.295) than the node (24.76%) portions, and it is significantly highest at the outer (33.43%), followed by inner (30.03%) and middle (21.98%) culm wall layers. The ash content is significantly highest in G. scortechinii (2.84%) followed by G. levis (1.30%), G. brang (1.26%), and G. wrayi (0.88%). Overall, the ash is significantly higher at the node (1.6%) than the internode (1.54%) portions. Opposite of α–cellulose and lignin, the ash is significantly highest at the inner (1.89%) culm wall, followed by the outer (1.52%) and lastly middle (1.28%) culm wall layers. The ethanol/toluene extractive is significantly highest in G. levis (9.23%), followed by G. wrayi (8.62%). The extractive content is not significantly different for G. brang (8.30%) and G. scortechinii (8.00%). The node (8.63%) has a significantly higher extraction content than the internode (8.46%), while it is significantly highest in the inner (13.42%) culm wall followed by the middle (7.21%) and lastly the outer (4.99%) layers of the culm wall (Razak et al. 2013).

In seven sympodial bamboo species grown in India, B. nutan Dehradun has 51.6% cellulose, 26% lignin, 8.1% hot water soluble, 7.1% cold water soluble, 28.1% NaOH soluble, and 4.2% ethanol/toluene extractive contents. The B. tulda has 56.2% cellulose, 24% lignin, 7.8% hot water soluble, 5.5% cold water soluble, 26.1% NaOH soluble, and 3.2% ethanol/toluene extractive. The B. arundinacea Allahabad has 47.7% cellulose, 26.5% lignin, 11.4% hot water soluble, 9.8% cold water soluble, 27.0% NaOH soluble, and 3.5% ethanol/toluene extractives. The B. pallida IWST, Bangalore has 46.5% cellulose, 20% lignin, 12.6% hot water soluble, 11.1% cold water soluble, 27% NaOH, and 5.2% ethanol/extractive contents. The B. bambos IWST, Bangalore has 50.5% cellulose, 21.5% lignin, 11.2% hot water soluble, 10% cold water soluble, 27.4% NaOH soluble, and 4.2% ethanol/toluene extractive.

The D. strictus Alalhabad has 53.6% cellulose, 25% lignin, 8.4% hot water soluble, 6.7% cold water soluble, 27.9% NaOH soluble, and 4.2% ethanol/toluene extractives. The D. strictus Teri has 53.4% cellulose, 27% lignin, 8.3% hot water soluble, 6.2% cold water soluble, 28.0% NaOH soluble, and 4.9% ethanol/toluene extractive contents (Kaur et al. 2016ab). The chemical composition of sympodial bamboo B. garuchokua, B. pallida, and B. assamica aged 3 years grown in India behave differently (Brahma and Brahma 2018). The α-cellulose is highest in B. pallida (38.29%), followed by B. garachokua (36.75%) and B. assamica (31.37%). Regardless of species, the α-cellulose content is highest at the outer culm all section followed by the middle (37.31%) and inner (35.90%) sections. In contrast, the holocellulose is highest in ascending order of B. assamica (60.18%), B. pallida (65.92%), and B. garuchokua (68.86%).

Overall, the holocellulose content is highest at the outer section (69.63%), followed by the middle (62.81%, and inner (62.51%) sections. The lignin content is highest in ascending order of B. assamica (18.29%), B. pallida (22.42%), and B. garuchokua (23.03%). Overall, the outer section has the highest lignin content (23.98%) and it is not much different with the inner (22.23%) and lastly the middle (17.78%) sections. The ash content is increased in ascending order of B. garachukua (0.99%), B. pallida (1.08%), and B. assamica (1.12%), while it is increased from the outer wall section (0.95%) toward the middle (1.04%) and inner (1.20%) sections. The hot water soluble is highest in B. garuchokua (5.90%) followed by B. pallida (5.70%) and lastly B. assamica (4.24%), while it gradually increases from outer section (4.43%) toward the middle (5.32%) and inner (6.09%) sections. The alcohol/toluene content is almost identical for B. garuchokua (4.12%) and B. pallida (4.37%), but it is lowest in B. assamica (3.44%). Across the culm wall, the extractive content is gradually decreased from the inner (4.55%) section toward the middle (4.02%) and outer sections (3.36%).

In relation to the culm section (Table 19), the contents of holocellulose, α-cellulose, lignin, ash, hot water soluble, cold water soluble, and 1% NaoH soluble are not significantly different with node or internode regions at the basal, middle, and top portions of sympodial bamboo D. asper aged 3 years ranging from 75.65% to 77.36%, from 67.07% to 69.64%, from 26.47% to 30.86%, from 0.92 to 2.29%, from 6.47 to 9.63%, from 4.23 to 14.05%, and from 23.40 to 26.78% (Kamthai and Puthson 2005). Almost all major chemical constituents in sympodial bamboo G. scortechinii aged 0.5, 1.5, 3.5, 5.5, and 6.5 years are relatively low at the youngest age of 0.5 years (Table 18). The starch content is low at the age of 1.5 years (0.6%) but increases to 3.5% at the age of 3.5 years and remain unchanged toward the later years. This is probably because no further increase of parenchyma length and lumen diameter occurred beyond the age of 3.5 years. The starch granule is situated or stored in vertically elongated cells of ground parenchyma (Liese and Weiner 1996).

The authors reported that younger 1-year-old bamboo culms do not contain any starch during the growing phase, because all the nutrients must be utilized immediately for metabolic processes. However, Mohmod et al. (1992) reported minor trace of starch content (0.8%) at the basal portion of 1-year-old G. scortechnii. Lignin content drastically increased at the age of 1.5 years (14.5%) and then gradually increased thereafter. No specific trend for alcohol/toluene extractive was observed, but it was high at age of 0.5, 3.5, and 6.5 years. The α-cellulose content remained unchanged, but the holocellulose content slightly increased beyond 3.5 years. The α-cellulose, holocellulose, hot water soluble, NaOH soluble, and ash contents in G. scortechinii are not significantly different with bamboo aged 1, 2, and 3 years (Table 20). The averages are 40.7%, 41.41%, and 40.49% for α-cellulose; 66.7%, 67.8%, and 67.9% for holocellulose; 6.3%, 5.9%, and 5.4% for hot water soluble; 19.6%, 19.2%, and 19.6% for NaOH soluble; and 11.0%, 11.1% and 11.4% for ash contents, respectively (Mohmod et al. 1994).

The lignin content is not significantly different in culm aged 1 (25.7%) and 2 years (24.9%), but significantly highest in the oldest culm (28.0%). The same trend occurs for cold water soluble and ethanol/toluene extractive. The average cold water soluble is 4.3%, 4.4%, and 5.5% in culm aged 1, 2, and 3 years, while it is 3.2%, 3.2%, and 3.5% for the ethanol/toluene extractives. Zhang et al. (2015) examined the chemical composition of F. fungosa aged 1, 2, and 3 years. The holocellulose content is not significantly different, with age ranging from 69.86% to 70.77%. Regardless of age, the holocellulose content is also not significantly different at the basal (70.11%), middle (69.99%), and top (70.56%) portions of the culm. Same as holocellulose, the lignin is not significantly different with age ranging from 22.66% to 24.21%. The alcohol/toluene extractive is significantly highest for the oldest culm (4.14%) and it is not significantly different for culm aged of 1 year (3.01%) and 2 years (3.22%). The ash content is significantly highest at a youngest age of 1 year (2.88%) but declines toward 2 (1.51%) and 3 years (1.40%). The silica content is significantly decreased in descending order of 1 year (0.48%), 2 years, (0.38%) and 3 years (1.40%).

In sympodial bamboo of D. hamiltonii (Zhan et al. 2016), the holocellulose content is significantly increased at the youngest age of 1 year toward the older age of 2 (68.7%) and 3 (76.7%) years. In contrast, the lignin content is not significantly different with ages ranging from 21.4% to 23.6%, but it is significantly different with the culm portion. The ethanol/toluene extractive content is significantly increased at the youngest age of 1 year (0.9%) toward the older aged of 2 years (1.2%) and 3 years (1.9%). The ash content is not significantly different with age ranging from 2.0% to 2.9%. In contrast to F. fungosa (Zhan et al. 2015), the silica content is significantly increased with age from 1 year (0.3%), 2 years (0.7%), and 3 years (2.1%) (see Fig. 2).

Fig. 2. The effect of ageing on the chemical properties in monopodial and sympodial bamboos

In relation to the culm portion (Table 19), the α-cellulose, lignin, holocellulose, cold water soluble, and ash contents in G. scortechinii aged 1, 2, and 3 years are not significantly different with the culm height (basal, middle, and top portions); ranging from 40.3% to 41.1%, 25.5% to 26.6%, 67.2% to 68.90%, 4.4% to 4.9%, and 1.10% to 1.13%, respectively. The hot water soluble is significantly increased at the basal (5.3%) toward the middle (6.0%) and top (6.5%) portions. A same trend occurs for NaoH soluble and ethanol/toluene extractives. The average NaoH soluble is 18.49% (basal), 19.8% (middle), and 20.1% (top), while it is 3.0% (basal), 3.3% (middle), and 3.6% (top) for the ethanol extractive contents (Mohmod et al. 1994). The holocellulose content in D. hamiltonii (Zhan et al. 2016) is not significantly different with portions ranging from 69.2% to 73.4%. The lignin content is significantly decreased in descending order of top (24.8%), middle (22.4%), and basal (21.60%) portions. Within the culm height, the extractive content is not significantly different with the culm portion ranging from 1.1% to 1.5%. The ash and silica contents are not significantly different with the culm portion ranging from 1.8% to 3.1% and 0.4% to 1.6% respectively.

The lignin content of F. fungosa aged 1, 2, and 3 years is significantly highest at the top (24.66%) but not significantly different from the basal (23.76%) portions. The middle portion has the lowest lignin content (21.86%). The ash content is not significantly different from the culm portion, ranging from 1.90% to 1.96%. Within the culm wall section, the silica content is significantly decreased in descending order of top (0.43%), middle (0.39%), and basal (0.33%) portions (Zhan et al. 2015). The maximum cellulose, hemicellulose, lignin, ash, silica, hot water soluble, cold water soluble, NaOH soluble, and ethanol/toluene extractive contents in monopodial bamboo are recorded for P. heterocycle (75.30%), P. edulis (29.66%), Sasa albomarginate Makin (39.76%), S. albomarginate Makin (3.38%), P. sp (0.13%), P. heterocycla (15.94%), P. heteroclada (13.57%), and P. mayeri (35.31%). While the minimum contents in monopodial bamboo are obtained in P. bambusoides (12.02%), M. baccifera (15.03%), P. bissetii McClure (14.69%), C. utilis (0.74%), B. garuechokua (0.99%), S. affinis (0.17%), P. bisseti McClure (1.68%), P. pubescens Mazel (2.38%), P. bambusoides (14.60%), and P. pubescens (1.60%) (Table 20).

In contrast, the maximum cellulose, hemicellulose, lignin, ash, silica, hot water soluble, cold water soluble, NaOH soluble, and ethanol/toluene extractive contents in sympodial bamboo are recorded by D. striticus (68.00%), S. affinis (25.41%), D. striticus (32.20%), D. sp (4.39%), S. funghpmii McClure (3.76%), B. sinaspinosa (9.91%), B. sinaspinsa McClure (10.53), B. textilis (32.27), and B. sinaspinosa (28.02%); while, the minimum contents for sympodial bamboo are recorded in B. sinanpinosa (17.10%), D. striticus (15.05%), D. sp (17.62%), B. garuechokua (0.99%), S. affinis (0.17%), O. travancorica (3.13%), T. sp (1.61%), D. hamiltonii (13.81%), and D. hamiltonii (0.9%).

Overall

Regardless of the rhizome, the overall monopodial type of bamboo has a significantly higher cellulose, hemicellulose, lignin, hot water soluble, cold water soluble, and 1% NaOH soluble (47.63%, 20.81%, 25.57%, 6.97%, 6.89%, and 28.09%) contents compared to the sympodial type of bamboo (40.42%, 14.24%, 24.33%, 5.75%, 5.61%, and 24.69%), respectively. In contrast, the sympodial type of bamboo has a significantly higher ash content (2.06%) compared to the monopodial type of bamboo (1.54%). Both the silica (0.27% and 0.92%) and ethanol/toluene extractive (4.72% and 7.20%) are not significantly different in monopodial and sympodial types of bamboo (Table 21).

Table 19. Chemical Properties in Monopodial and Sympodial Bamboos

Table 20. Statistical Reanalysis of the Chemical Properties in Monopodial and Sympodial Bamboos

NS –Not significant at P > 0.1, * – significant at P < 0.1, **- significant at P < 0.05, and ***- significant at P < 0.01

SUSCEPTIBILITY AND RESISTANCE TO FUNGI

Akin to other monocotyledon and dicotyledon plants, bamboo contains structural organic chemicals, inorganic chemicals, and extractives. It is easily decayed by micro-organisms, such as mold, fungi, and insects, under appropriate conditions. Although it is well known that the bamboo has been used by human and animals, a few hundred years ago both in tropic and temperate climate, minimal information is known regarding its susceptibility to different fungi, mode of attack, resistance, and the classes. In the earliest research on susceptibility of bamboo to micro-organism, Liese (1985) reported that it is attacked especially by insects at ambient temperature; while the white, brown, and soft rot fungi are able to attack above the bamboo fibre saturation point. Liese (1985) and George (1985) both agree that the bamboo service life is estimated between 6 months to 3 years when in contact with soils. This finding is in a good agreement with Kaur et al. (2016b), which reveals that the untreated D. strictcus damages at 60% within 3 months and is completely destroyed within 6 months of exposure to termites.

The soft rot decay on the different ages of Sinobambusa tootsik (Makino) is characterized by cavities only in the fibre cell walls, but parenchyma and vessel components are unattacked. The rate of decaying is influenced by the location of the fibre, culm age, and the degree of lignification of individual fibers (Murphy et al. 1991). In bamboo, the brown rot fungi consume the carbohydrate fraction of the walls and modifying lignin during the process. The white rot is able to consume both the carbohydrate and lignin fraction of the walls, while the soft rot consumes the carbohydrate fraction but probably not the lignin. Each fungal type gives its own microscopic characteristics at the cell wall levels after the decaying process. Brown rot gives indication of widespread amorphous degradation of the bulk cell wall, and white rot gives indication of localized degradation adjacent to the hyphae (bore holes and erosion troughs). The soft rot shows indication of discrete cavities within the secondary wall, erosion of the wall from the lumen, and possibly, a generalized dissolution of the wall (Sulaiman and Murphy 1994).

The compound middle lamellae (CML) encompassing the cell corner regions are preferentially degraded in P. pubescens at an early stage of decaying process by white rot Lentinus edodes. The fibre secondary walls remain largely intact during this period. The preferential degradation of the CML compared to the fiber secondary walls strongly involves not only enzyme systems of the white rot fungus, but also a relationship to physicochemical properties of bamboo cell walls, particularly the influence of lignin composition and distribution (Kim et al. 2008). Same as the mode of white rot attacks, the CML in P. pubescens fibers are degraded at an early stage of decaying process by the G. trabum, which is confirmed by the distribution of H-unit lignin in the middle lamella. The absorbance bands assigned to lignin are decreased in the Fourier transform infrared spectra. The decay of bamboo fiber walls by G. trabeum is influenced by lignin distribution in the fiber walls. Polylaminate layers in bamboo fibers had an influence on cell wall degradation, with the narrow layers showing greater resistance than the broad layers (Cho et al. 2008).

In G. scortechinii decayed by white rot (Coriolus versicolor) and brown rot (Coniophora puteana) fungi, the mode of hyphae attacks is penetration of the larger methaxylem vessel cell and further to the neighbor parenchyma and fibre cells through small pit membrane cells (Norul Hisham et al. 2012). Similarly, the hyphae of white rot P. chrysosporium and brown rot G. trabum attack the P. edulis through the parenchyma cells. Places near the inner skin are the most frequently attacked, and the vessels are the primary paths for the spread of mycelium. The bamboo crystalline structure decreases after being decayed by both fungi and the crystalline cellulose in bamboo is well deteriorated. The white rot strongly degrades the lignin component, then the hemicellulose and cellulose components. The brown-rot selectively degrades the hemicellulose fraction over cellulose and lignin. The decaying process is accompanied by oxidation and hydrolysis surface reactions, but the reaction rates behave differently for cellulose and lignin (Xu et al. 2013).

In the decay resistance class of several bamboo species (Wei et al. 2013), the G. angustifolia is rather resistant to Trametes versicolor and same with D. asper against Chaetomium globosum. For brown-rot fungi, the Coniophora puteana and Gloeophyllum trabeum produce a low mass loss (maximum 2.9%). In contrast, the white-rot, T. versicolor yields the highest decay (max. 15.3%), while the Schizophyllum commune is considered as inactive (max. 3.2%). For soft-rot fungi, Ch. globosum gives a medium degradation (max. 9.6%) and Paecilomyces variotii exhibits low degradation (max. 3.1%). The decay resistance depends on the bamboo species, type of fungi, the standard of testing, incubation period, and its environmental conditions. The deterioration is always expressed in percentage weight loss of oven-dried specimen before and after the exposure. For instance, the G. scortechinii exposed to brown rot Coniophora puteana showed 8.90% of weight loss after 8 weeks incubation period (Norul Hisham et al. 2012), while it was 18.70% weight loss after 52 weeks of incubation (Schmidt et al. 2013). The D. asper recorded 15.3% weight loss after it was exposed to Schizosphyllum commune for 12 weeks (Suprapti 2010), and it was only 4.3% weight loss after it was exposed to the same fungus for 52 weeks (Schmidt et al. 2013). The P. pubescens showed only 5.3% weight loss after 52 weeks was exposed to Gloeophyllum trabeum (Schmidt et al. 2011), and it recorded 54.36% of weight loss after it was exposed for 8 weeks (Li et al. 2020). The weight loss of P. pubescens decayed by brown rot Coniophora puteana contact with soil was 6.3% compared to without soil contact, 25% (Schmidt et al. 2011)

Overall

Regardless of fungi (Table 22), the decay resistance is not significantly different for both monopodial (16.72%) and sympodial (14.22%) bamboo. The resistance is also not significantly different with fungi, either white, brown, or soft rot for both monopodial (19.06%, 15.92%, and 11.05%) and sympodial (14.03%, 12.88%, and 17.38%) bamboos, respectively. Generally, in all type of fungus, the monopodial bamboo is less resistant toward white, brown, and soft rot compared to the sympodial bamboo.

Table 21. Weight Loss of Monopodial and Sympodial Bamboos Decayed by Fungi

Table 22. Statistical Analysis of Weight Loss of Decayed Monopodial and Sympodial Bamboo

DF– Degree of freedom, F– F ratio, NS is not significant at P > 0.1, *** is significant at P < 0.0. The value in parentheses is standard deviation.

CONCLUSIONS

The bamboo properties are not only different with genera, species, and site location, but also with rhizome type. The monopodial bamboo has shorter sprouting time, growth phase, diameter breast height, and overall height than the sympodial bamboo.
Anatomically, the monopodial bamboo contains a higher radial length and tangential diameter, but its radial length/tangential diameter is smaller than the sympodial bamboo. The vascular bundle frequency is higher in monopodial bamboo.
The monopodial bamboo contains higher α-cellulose, hemicellulose, lignin, hot water soluble, cold water soluble, and 1% NaOH soluble contents. Monopodial bamboo has a higher tensile and modulus of rupture but there is not much difference in the compression strength.
The fibre length and diameter are longer and wider in sympodial bamboo, but the fibre lumen diameter and wall thickness are not different in either monopodial or sympodial bamboos.
The proportion of metaxylem vessel diameter is higher in sympodial bamboo but the proportion of fibre and parenchyma are not much different for monopodial and sympodial bamboos. The volumetric shrinkage is higher in sympodial bamboo, but the density is not much different for both rhizome types.
Sympodial bamboo has a significantly higher ash content, but both the silica and ethanol/toluene extractive contents are not much different from either monopodial or sympodial bamboo. Overall, the sympodial bamboo is more resistant toward white, brown, and soft rot compared to the monopodial bamboo.

ACKNOWLEDGMENTS

The authors are grateful for the support of the Ministry of Higher Education (Grant No: PRGS/1/2019/WAB07/UPM/02/1-5534900)

REFERENCES CITED

Amada, S., Munekata, T., Nagase, Y., Ichikawa, Y., Kirigai, A., and Zhifei, Y. (1996). “The mechanical structures of bamboo in viewpoint of functionally gradient and composite materials,” Journal of Composite Material 30(7), 800-819. DOI: 10.1177/002199839603000703

Awalludin, D., Mohd Azreen, M. A., Osman, M. H., Mohd Warid, H., Mohammed, A. I., Lee, H. S., and Nor hasanah, A. S. L. (2017). “Mechanical properties of different bamboo species,” MATEC Web of Conferences 138(4), article ID 01024. DOI: 10.1051/matecconf/201713801024

Azmy, H. M., and Razak, A. O. (1991). “Field identification of twelve commercial Malaysian bamboos,” in: FRIM Technical Information No. 25, Forest Research Institute Malaysia, Kepong, Malaysia.

Banik, R. L. (1993). “Periodicity of culm emergence in different bamboo species of Bangladesh,” Annals of Forestry 1(1), 13-17.

Banik, R. L. (2015). “Morphology and growth,” in: Bamboo. The plant and its uses, W, Liese & M, Kohl. (Eds.), 43-90.

Bharma, S., and Brahma, B. K. (2018). “Chemical composition: The prerequisite criteria for bamboo utility, (Study of Bambusa garauchokua, Bambusa pallida and Bambusa assamica of Kokkrajhar district of Btc, Assam, India),” Journal for Advance Research in Applied Sciences 5(4), 1-9.

Bhonde, D., Nagarnaik, P. B., Parbat, d. K., and Waghe, U. P. (2014). “Physical and mechanical properties of bamboo (Dendrocalamus strictus),” International Journal of Scientific and Engineering Research 5(1), 455-459.

Brito, F. M. S., Raes, J. B., Oliveira, J. T. D. A., Arantes, M. D. C., and Dudecki, L. (2020). “Chemical characterisation and biological resistance of thermally treated bamboo,” Construction and Building Materials 262, article ID 120033. DOI: 10.1016/j.conbuildmat.2020.120033

Camargo, J. C. (2006). Growth and Productivity of the Bamboo Species Guadua angustifolia Kunth in the Coffee Region of Colombia, Ph.D. Dissertation, University of Göttingen, Göttingen, Germany.

Chang, V. S., and Holtzapple, M. T. (2000). “Fundamental factors affecting biomass enzymatic reactivity,” Applied Biochemistry and Biotechnology 84, 5-37. DOI: 10.1385/ABAB:84-86:1-9:5

Chen, M., Ye, L., Li, H., Wang, G., Chan, Q., Fang, C., and Dai, C. (2020). “Flexural strength and ductility of moso bamboo,” Construction and Building Materials 246, article 118418. DOI: 10.1016/j.conbuildmat.2020.118418.

Chen, T. H., Wang, D. H., and Chung, H. Y. (2012). “The growth and biomass of Bambusa stenostachya plantation at Zeochen Area in Tainan City,” Quarterly Journal of Chinese Forestry 45(3), 341-350. DOI: 10.30064/QJCF.201209.0005

Cho, C. H., Lee, K. H., Kim, J. S., and Kim, Y. S. (2008). “Micromorphological characteristics of bamboo (Phyllostachys pubescens) fibre degraded by a brown rot fungus, (Gloeophyllum trabum),” Journal of Wood Science 54(3), 261-265. DOI: 10.1007/s10086-007-0937-1

Clark, L. G., Londoño, X., and Ruiz-Sanchez, E. (2015). “Bamboo taxonomy and habitat,” in: Bamboo, W. Liese, and M. Köhl (Eds.), Springer, Cham, Switzerland, pp. 1-30. DOI: 10.1007/978-3-319-14133-6_1

Correal, J., and Camargo, J. (2010). “Influence of age and height position on Colombian Guadua angustifolia bamboo mechanical properties,” Maderas: Ciencia y Technologia 12(2), 105-113. DOI: 10.4067/S0718-221X2010000200005

De Vos, V. (2010). Bamboo for Exterior Joinery: A Research in Material and Market Perspectives, B.Sc. Thesis, University of Applied Sciences, Van Hall Larenstein, Leeuwarden, Netherlands.

Deluca, L. T. (2016). “Highlights of solid rocket propulasion history,” Springer Aerospace Technology 1015-1032. DOI:10.1007/978-3-319-22748_42.

Dixon, P. G., and Gibson, L. J. (2014). “The structure and mechanics of Moso bamboo material,” The Journal of the Royal Society Interface 11(99), article ID 20140321. DOI: 10.1098/rsif.2014.0321 DOI: 10.1007/s004680000084

Espiloy, Z. B. (1987). “Mechanical properties and anatomical relationship of some Philippines bamboos,” in: Proceedings of the International Workshop on Bamboo, A. N. Rao, G. Dhanarajan, and C. B. Sastry (eds.), The Chinese Academy of Forestry and International Development Research Centre, Hangzhou, China, pp. 257-265.

Fangchun, Z. (2001a). “Annual highlights. International bamboo and rattan organisation,” in: Selected Works of Bamboo Research, The Bamboo Research Editorial Committee, Nanjing Forestry University Publisher, Nanjing, China.

Fangchun, Z. (2001b). Cultivation and Integrated Utilisation on Bamboo in China, China National Bamboo Research Centre Publisher, Hangzhou, China.

Fei, B., Gao, Z., Wang, J., and Liu, Z. (2016) “Biological, anatomical, and chemical characteristics of bamboo secondary xylem biology,” in: Secondary Xylem Biology, Y. S. Kim, R. Funada, and A. P. Singh (eds.), Academic Press, Cambridge, MA, USA, pp. 283-306. DOI: 10.1016/B978-0-12-802185-9.00014-0

Fernandez, E. C., Palijon, A. M., Liese, W., Esguera, F. L and Murphy, R. J. (2003). “Growth performance of two bamboo species in new plantation,” Journal of Bamboo and Rattan 2(3), 225-239.

Fujino, T., and Itoh, T. (1998). “Changes in the three dimensional architecture of the cell wall during lignification of xylem,” Cells in Eucalyptus Tereticornis 52(2), 111-116. DOI: 10.1515/hfsg.1998.52.2.111

Gao, R. L., Lin, Z. P., and Wang, J. L. (2000). “Growth dynamics of bamboo shoot and young bamboo of Dendrocalamopsis oldhami,” Subtropical Plant Science 29(2), 27-30.

George, J. (1985). “Preservative treatment of bamboo, rubber wood and coconut palm. Simple methods for treating building timbers,” in: Preservation of Timber in the Tropics, W. P. K. Findlay (ed.), Springer Science+Business Media, Dordrecht, Netherlands, pp. 233-247. DOI: 10.1007/978-94-017-2752-5_11

Gratani, L., Crescente, M. F., Varone, L., and Fabrini, G. (2008). “Growth pattern and photosynthetic activity of different bamboo species growing in the Botanical Garden of Rome,” Flora – Morphology, Distribution, Functional Ecology of Plants 203(1), 77-84. DOI: 10.1016/j.flora.2007.11.002

Grosser, D., and Liese, W. (1971). “On the anatomy of Asian bamboos, with special reference to their vascular bundles,” Wood Science and Technology 5, 290-312. DOI: 10.1007/BF00365061

Grosser, D., and Liese, W. (1973). “Present status and problems of bamboo classification,” Journal of the Arnold Arboretum 54(2), 293-308. DOI: 10.5962/p.184524

Hafrén, J., Fujino, T., and Itoh, T. (1999). “Changes in cell wall architecture of differentiating tracheids of Pinus thunbergii during lignification,” Plant and Cell Physiology 40(5), 532-541. DOI: 10.1093/oxfordjournals.pcp.a029574

Hagarth, N. J., and Belcher, B. (2013). “The contribution of bamboo to household income and rural livelihoods in a poor and mountainous county in Guangxi, China,” International Forestry Review, 15(1), 71–81. DOI:10.1505/146554813805927237

Hamdan, H. and Mohmod, A. L. (1992). “Effects of physicoanatomical characteristics on machining properties of Malaysian bamboos,” Bamboo Journal 10, 57-65.

Hamdan, H., Anwar, U. M. K., Zaidon, A., and Mohd Tamizi, M. (2009). “Mechanical properties and failure behaviour of Gigantochloa scortechinii,” Journal of Tropical Forest Science 21(4), 336-344.

Huang, K., and Ma, B. (1994). “Study on the growth regulation of young shoots from Phyllostachys makbzoi,” Journal of Fujian College of Forestry 14, 291-294.

Huang, X. Y., Qi, J. Q., Xie, J. L., Hao, J. F., Qin, B. D., and Chen, S. M. (2015). “Variation in anatomical characteristics of bamboo, Bambusa rigida,” Sains Malaysiana 44(1), 17-23. DOI: 10.17576/jsm-2015-4401-03

Huang, X. Y., Xie, J. L., Qi, J. Q., Hao, J. F., Jiang, X. Q., and Hu, W. H. (2014). “Investigation of the physical and mechanical properties and chemical composition of Bambusa rigida before and after accelerated aging,” BioResources 9(2), 3174-3184. DOI: 10.15376/BIORES.9.2.3174-3183

Itoh, T. (1990). “Lignification of bamboo (Phyllostarchys heterocycla Mitf.) during its growth,” Holzforschung 44(3), 191-200. DOI: 10.1515/hfsg.1990.44.3.191

Jeon, W. S., Kim, Y. I., Lee, J. A., and Kim, A. R. (2018). “Anatomical characterisation of three Korean bamboo species,” Journal of the Korean Wood Sience and Technology 46(1), 29-37. DOI: 10.5658/WOOD.2018.46.1.29

Jiang, Z. (2002). Bamboo and Rattan in the World, Liaoning Science and Technology Press, Shenyang, China

Jin, A., Shao, X., Qiu, S., and Zhang, F. (1999). “Biological characteristics of Phyllostachys heteroclada,” Journal of Zhejiang Forestry College 16(3), 238-241.

Ju, Z., Zhan, I., Cui, J., Brosse, N., Zhang, H., and Hong, L. (2021). “Eco-friendly method to improve the durability of different bamboo (Phyllostachys pubescens, Moso) sections by silver electrochemical treatment,” Industrial Crops and Products 172, article ID 113994. DOI: 10.1016/j.indcrop.2021.113994

Kamthai, S., and Puthson, P. (2005). “The physical properties, fibre morphology and chemical composition of sweet bamboo (Dendrocalamus asper Backer),” Kasertsart Journal (Natural Science) 39, 581-587.

Kaur, P. J., Kardam, V., Pant, K. K., Naik, S. N., and Satya, S. (2016a). “Characterisation of commercially important Asian bamboo species,” European Journal of Wood and Wood Products 74(1), 137-139. DOI: 10.1007/s00107-015-0977-y

Kaur, P. J., Pant, K. K., Satya, S., and Naik, S. N. (2016b). “Field investigations of selectively treated bamboo species,” European Journal of Wood and Wood Products 74(5), 771-773. DOI: 10.1007/s00107-016-1055-9

Kim, A., Im, M., Yim, N. H., Jung, Y. P., and Ma, J. Y. (2013). “Aqueous extract of Bambusae caulis in Taeniam inhibits PMA-induced tumor cell invasion and pulmonary metastasis: Suppression of NFkB activation through ROS signaling,” PLoS ONE 8(10), article e78061. DOI: 10.1371/journal.pone.0078061

Kim, J. S., Lee, K. H., Cho, C. H., Koch, G., and Kim, Y. S. (2008). “Micromorphological characteristics and lignin distribution in bamboo (Phyllostachys pubescens) degraded by the white rot fungus Lentinus edodes,” Holzforschung 62(4), 481-487. DOI: 10.1515/HF.2008.080

Kiruba, S., Jeeve, S., Manohardas, S., and Kannan, D. (2007). “Bamboo seed as a mean to sustenance of the indigenous community,” Indian Journal of Traditional Knowledge 6(1), 199-203.

Lee, A. W. C., and Addis, S. C. (2001). “Growth characteristics of Moso bamboo in South Carolina,” Forest Product Journal 53, 88-89.

Lee, A. W., Bai, X., and Peralta, P. N. (1994). “Selected physical and mechanical properties of giant timber bamboo grown in South Carolina,” Forest Products Journal 44(9), 40-46.

Leoncio, M. C. A. (2017). “Comparative mechanical properties of selected bamboo species,” International Journal of Precious Engineering Research and Application 2(1), 1-8.

Li, W., Liu, M., Zhai, H., Wang, H., and Yu, Y. (2020). “Preparing highly durable bamboo materials via bulk furfurylation,” Construction and Building Materials 262, article ID 120726. DOI: 10.1016/j.conbuildmat.2020.120726

Li, X. (2004). Physical, Chemical, and Mechanical Properties of Bamboo and its Utilization Potential for Fiberboard Manufacturing, Master’s Thesis, Louisiana State University and Agricultural and Mechanical College, Baton Rouge, LA, USA.

Li, Z. (2003). Diversity and Ecology of Mountain Bamboos in the Shennongjia National Reserve of Central China Implications for Resource Management and Biodiversity Conservation, Cuvillier Verlag, Göttingen, Germany.

Li, Z. C., Fu, M. Y., and Xu, D.Y. (2003). “Bamboo ecosystem and carbon dioxide sequestration,” Journal of Bamboo Research 4, 1-6.

Li, Z. H., Denich, M., and Porsch, T. (2005). “Growth behaviour of Phyllostachys nigra var henonis (Bambusoides) in central China,” Journal of Forestry Research 16(3), 163-168. DOI: 10.1007/BF02856808

Liese, W. (1985). Bamboos-Biology, Silvics, Properties, Utilisation, TZ- Verlag & Print GmbH, Roßdorf, Germany.

Liese, W. and Kohl, M. (2015). Bamboo. The Plant and Its Uses. Springer, Switzerland. 346p.

Liese, W., and Weiner, G. (1996). “Ageing of bamboo culms. A review,” Wood Science and Technology 30, 77-89. DOI: 10.1007/bf00224958

Lin, J., Yuxi Hu, X. H., Kuang, T., and Ceulemons, R. (2002). “Lignification and lignin heterogeneity for various age classes of bamboo (Phyllostachys pubescens) stems,” Physiologia Plantarium 114(2), 296-302. DOI: 10.1034/j.1399-3054.2002.1140216.x

Liu, C. T., Li, W. J., and Wang, Y. H. (1998). “Properties and utilization of laminated bamboo,” TFRI Extension Series 96, 507-514.

Liu, W., Hui, C., Wang, F., Wang, M., and Liu, G. (2018). “Review of the resources and utilization of bamboo in China,” in: Bamboo – Current and Future Prospects, H. P. S. Abdul Khalil (ed.), IntechOpen, London, UK. DOI: 10.5772/intechopen.76485

Long, X. W., and Jiang, X. (1996). “Studies on the fertilization of Sinocalamus affinis,” Journal of Fujian Forestry Science and Technology 23(2), 38-43.

Lü, C. M. (2001). Cultivation and Management of Bamboo Forests, TFRI Extension Series, No. 135, Taiwan Forestry Research Institute Publisher, Taipei, Taiwan.

Luo, J., Lian, C., Liu, R., Zhang, S., Yang, F., and Fei, B. (2019). “Comparison of metaxylem vessel and pits in four sympodial bamboo species,” Scientific Reports 9, article 10826. DOI: 10.1038/s41598-019-47419-7

Malanit, P. (2009). The Suitability of Dendrocalamus asper Backer for Oriented Strand Lumber, Ph.D. Thesis, University of Hamburg, Germany.

Maoyi, F., Xiasheng, Y., and Shenxui, J. (2007). Technical Manual on Utilisation of Sympodial Bamboos, China Forestry Publishing House, Beijing, China.

Marsoem, S. N., Setiaja, F., Kim, N. H., Sulistyo, J., Irawati, D., Nugroho, W. D., and Pertiwi, Y. A. B. (2015). “Fiber morphology and physical characteristics of Gigantochloa atter at three different ages and heights of culms for better utilization,” Journal of the Korean Wood Science and Technology 43(2), 145-155. DOI: 10.5658/WOOD.2015.43.2.145

McClure, F. A. (1966). The Bamboos: A Fresh Perspective, Harvard University Press, Cambridge MA, USA.

Mera, F. A. T., and Xu, C. (2014). “Plantation management and bamboo resource economics in China,” Maderas: Ciencia y Tecnología 7(1), 1-12. DOI: 10.18779/cyt.v7i1.181

Mohamed, J., Hazandy, A. H., Ahmad, A. N., and Nik Mohd, M. N. A. (2019). “Chemical attributes of Gigatochloa scortechinii bamboo rhizome in relation with hydraulic conductance,” BioResources 14(4), 8155-8173. DOI: 10.15376/biores.14.4.8155-8173

Mohmod, A. L. and Phang, M. T. (2001). “The mechanical properties of Bambusa vulgaris and Gigantochloa scortechinii grown in Peninsular Malaysia,” Journal of Tropical Forest Products 7(1), 111-125.

Mohmod, A. L., Khoo, K. C., Jamaludin, K., and Abdul Jalil, H. A. (1994). “Fiber morphology and chemical properties of Gigantochloa scortechinii,” Journal of Tropical Forest Science 6, 397-407.

Mohmod, A. L., Ashaari, A., Jamaluddin, K. and Zim, J. M. (1993). “Effect of anatomical characteristics on physical and mechanical properties of B. blumeana,” Journal of Tropical Forest Science 6, 159-170.

Mohmod, A. L., Tarmeze, W. A. and Fauzidah, A. (1990). “Anatomical features and mechanical properties of three Malaysian bamboos,” Journal of Tropical Forest Science 2(3), 227-234.

Mohmod, A. L., Khoo, K. C. and Nor Azah, M. A. (1992). “Carbohydrates in some natural stand bamboos,” Journal of Tropical Forest Science 4(4), 310-316.

Murphy, R. J., Alvin, K. L., and Tan, Y. F. (1991). “Development of soft rot decay in the Bamboo sinobambusa tootsik,” IAWA Journal 12(1), 85-94. DOI: 10.1163/22941932-90001209

Naithani, H. B., Bisht, N. S., and Singsit, S. (2010). Distribution of Bamboo Species in Manipur, Forest Department, Government of Manipur, Imphal, India.

Nakashima, J., Mizuno, T., Takabe, K., Fujita, M., and Hiroshi, S. (1997). “Direct visualization of lignifying secondary wall thickenings in Zinnia elegans cells in culture,” Plant and Cell Physiology 38(7), 818-827. DOI: 10.1093/oxfordjournals.pcp.a029240

Noor Zuraida, J., Mansur, A., and Azmi, I. (2013). “Study on compressive strength of semantan bamboo culm (Gigantochloa scortechinii),” Applied Mechanics and Materials 330, 96-100. DOI: 10.4028/www.scientific.net/AMM.330.96

Nordahlia, A. S., Uyup, M. K. A., Husain, H., Mohmod, A. L., and Awalludin, M. F. (2019). “Anatomical, physical, and mechanical properties of thirteen Malaysian bamboo species,” BioResources 14(2), 3925-3943. DOI: 10.15376/biores.14.2.3925-3943

Norul Hisham, H., Mohmod, A.L. and Sulaiman, O. (2003). “Decay resistance of bamboo (Gigantochloa scortechinii) compared to 24 Malaysian hardwood,” XII World Forestry Congress, Quebec, Canada.

Norul Hisham, H., Othman, S., Azmy, M., and Norasikin, A. L. (2012). “The decay resistance and hyphae penetration of bamboo Gigantochloa scortechinii decayed by white and brown rot fungi,” International Journal of Forestry Research 2012, article ID 572903. DOI: 10.1155/2012/572903

Norul Hisham, H., Othman, S., Rokiah, H., Abdul Latif, M., Ani, S., and Mohd Tamizi, M. (2006). “Characterisation of bamboo Gigantochloa scortechinii at different age,” Journal of Tropical Forest Science 18(4), 236-242.

Osmastos, B. B. (1918). “Rate of growth of bamboo,” India Forester 44(2), 52-57.

Panee, J. (2009). “Bamboo extract in the prevention of diabetes and breast cancer,” in: Complementary and Alternative Therapies and the Aging Population, R. R. Watson (ed.), Academic Press, San Diego, CA, USA, pp. 159-177. DOI: 10.1016/B978-0-12-374228-5.00009-3

Parameswaran, N., and Liese, W. (1976). “On the fine structure of bamboo fibres,” Wood Science and Technology 10, 231-246. DOI: 10.1007/BF00350830

Parameswaran, N., and Liese, W. (1980). “Ultrastructure aspects of bamboo species,” Cellulose Chemistry & Technology 14, 587-609.

Poonia, P. K., Deepa, S. R., Kumar, M., and Kumar, M. (2021). “Viability of wood decaying fungal mycelium after microwave radiation of bamboo culm,” Maderas: Ciencia y Tecnologia 23(4), 1-6. DOI: 10.4067/s0718-221×2021000100404

Qin, Z., Taylor, A., and Huang, J. Y. (1993). “Research into Fargesia robusta biological characteristics,” Journal of Bamboo Research 12(1), 16–17.

Raka, I. D. N., Alit Wiswasta, I. G. N., and Made Budiasa, I. (2011). “Pelestarian Tanaman Bambu sebagai UpayaRehabilitasi Lahan dan Konservasi Tanah di Daerah Sekitar Mata Air pada Lahan Marginal di Bali Timur [Conservation of bamboo plants as an effort for land rehabilitation and soil conservation in the area around springs on marginal land in East Bali],” Agrimeta 1(1), 1-11.

Ram, N., Singh, L., and Kumar, P. (2010). “Bamboo plantation diversity and its economic role in North Bihar, India,” Nature and Science 8(11), 111-115.

Rao, A. N., Ramanatha Rao, V., and Williams, J. T. (1998). Priority Species of Bamboo and Rattan, International Plant Genetic Resources Institute, International Network for Bamboo and Rattan, Rome, Italy.

Razak, W., Mohd Tamizi, M., Othman, S., Aminuddin, M., Affendy, H., and Khalid, I. (2010). “Anatomical and physical properties of cultivated two and four years old Bambusa vulgaris,” Sains Malaysiana 39(4), 571-579.

Razak, W., Mohd Tarmeze, M., Mohammed Abdus, S., Mahmud, S., Hashim, W. S., and Mohd Sukhairi, M. R. (2013). “Chemical composition of four cultivated tropical bamboo in Genus Gigantochloa,” Journal of Agricultural Science 5(8), 66-75. DOI: 10.5539/jas.v5n8p66

Riaño, N. M., Londoño, X., López, Y., and Gómez, J. H. (2002). “Plant growth and biomass distribution on Guadua angustifolia Kunth in relation to ageing in the Valle del Cauca – Colombia,” The Journal of the American Bamboo Society 16(1), 43-51.

Sattar, M. A., Kabir, M. F and Battacharjee, D. K. (1994). “Effect of age and height position of Muli (Melocanna baccifera) and Borak (Bambusa balcooa) bamboos on their physical and mechanical properties,” FORSPA NO.6. IDRC/FAO/UNDP, 183-187.

Schmidt, O., Sheng, W. D., Liese, W., and Wollenberg, E. (2011). “Fungal degradation of bamboo samples,” Holzforschung 65(6), 883-888. DOI: 10.1515/HF.2011.084

Schmidt, O., Wei, D. S., Tang, T. K. H., and Liese, W. (2013). “Bamboo and fungi,” Journal of Bamboo and Rattan 12, 1-14.

Seki, T., Kida, K., and Maeda, H. (2010). “Immunostimulation-Mediated anti-tumor activity of bamboo (Sasa senanensis) leaf extracts obtained under ‘vigorous’ condition,” Evidence-Based Complementary and Alternative Medicine 7(4), 447-457. DOI: 10.1093/ecam/nen026

Shahril, A. B., and Mansur, A. (2009). “Effect of culm height levels and node presence on mechanical properties and fracture modes of Gigantochloa scortechinii strips loaded in shear parallel to grain,” The Journal of American Bamboo Society 22(1), 41-44.

Shao, Z., Fang, C., Huang, S., and Tian, G. (2010). “Tensile properties of moso bamboo (Phyllastochys pubescens) and its composites with respect to its fibre-reinforced composite structure,” Wood Science and Technology 44(4), 655-666. DOI: 10.1007/s00226-009-0290-1

Sharma, M., Sharma, C. L., and Laishram, D. (2017). “Variation in anatomical and physical properties of some Schizostachyum species of Manipur, India,” Journal of Indian Wood Science 14(1), 79-90. DOI: 10.1007/s13196-017-0191-0

Shimokawa, T., Ishida, M., Yoshida, S., and Nojiri, M. (2009). “Effects of growth stage on enzymatic saccharification and simultaneous saccharification and fermentation of bamboo shoots for bioethanol production,” Bioresource Technology 100(24), 6651-6654. DOI: 10.1016/j.biortech.2009.06.100

Srivaro, S., and Jakranod, W. (2016). “Comparison of physical and mechanical properties of Dendrocalamus asper Backer specimens with and without nodes,” European Journal of Wood and Wood Products 74, 893-899. DOI: 10.1007/s00107-016-1048-8

Sulaiman, O., and Murphy, R. J. (1994). “Soft rot decay in bamboo,” Material und Organismen 28(3), 167-195.

Suprapti, S. (2010). “Decay resistance of five Indonesian bamboo species against fungi,” Journal of Tropical Forest Science 22(3), 287-294.

Suzuki, K., and Itoh, T. (2001). “The changes in cell wall architecture during lignification of bamboo, Phyllostachys aurea Carr,” Trees 15, 137-147.

Tomak, E. D., Topologlu, E., Ay, N., and Yilidz, U. C. (2012). “Effect of accelerated aging on some physical and mechanical properties of bamboo,” Wood Science and Technology 46, 905-918. DOI: 10.1007/s00226-011-0454-7

Tomak, E. D., Topaloglu, E., Gumuskaya, E., Yildiz, U. C. and Ay, N. (2013). “An FT-IR study of the changes in chemical composition of bamboo degraded by brown rot fungi”, International Biodeterioration & Biodegradation 85,131-138. doi.org/10.1016/j.ibiod.2013.05029

Tripathi, S. K., Muhra, O. P., Bhardway, N. K., and Varadhan, R. (2018). “Pulp and papermaking properties of bamboo species Melocanna baccifera,” Cellulose Chemistry and Technology 52(1-2), 81-88.

Tsuyama, T., Shimada, N., Motoda, T., Matsushita, Y., Kijidani, Y., Fukushima, K., and Kamei, I. (2017). “Lignification in developing culms of bamboo Sinobambusa tootsik,” Journal of Wood Science 63, 551-559. DOI: 10.1007/s10086-017-1651-2

Ueda, K. (1960). Studies on the Physiology of Bamboo with Reference to Practical Application, Kyoto University Forests Publisher, Kyoto, Japan.

Wang, D. H., and Chen, T. H. (2015). “Bamboo resources and carbon storage in Taiwan,” in: 10^th World Bamboo Congress, Damyang-gun, Korea, pp. 1-18.

Wang, D., and Shen, S. (1987). Bamboos of China, Timber Press, Portland, OR, USA.

Wang, H., An, X., Li, W., Wang, H., and Yu, Y. (2014). “Variation of mechanical properties of single bamboo fibers (Dendrocalamus latiflorus Munro) with respect to age and location in culms,” Holzforschung 68(3), 291-297. DOI: 10.1515/hf-2013-0081

Wang, J. X., Ma, Z. G., Liu, C. X., and Gan, L. M. (1991). “Preliminary study on the growth and development roles of Fargesia denuduta bamboo,” JoumaI of Bamboo Research 10(3), 38-48.

Wang, J., Chen, T. H., Chung, H., Li, T., and Liu, C. P. (2009). “Structures, aboveground biomass, carbon storage of Phyllostachys pubescens stands in Huisun experimental forest station and Shi-Zhuo,” Quarterly Journal of Forestry Research 31(4), 17-26. DOI: 10.29898/SHBQ.200912.0002

Wang, Q., Wu, X., Yuan, C., Lou, Z., and Li, Y. (2020). “Effect of saturated steam heat treatment on physical and mechanical properties of bamboo,” Molecules 25(8), Article Number 1999. DOI: 10.3390/molecules25081999

Wang, R., Wang, K., Zhou, M., Xu, J., and Jiang, J. (2021). “Efficient fractionation of moso bamboo by synergistic hydrothermal-deep eutectic solvents pre-treatment,” Bioresource Technology 328(9), article ID 124873. DOI: 10.1016/j.biortech.2021.124873

Wang, Y., Zhan, H., Ding, Y., Wang, S., and Lin, S. (2016). “Variability of anatomical and chemical properties with age and height in Dendrocalamus brandisiii,” BioResources 11(1), 1202-1213. DOI: 10.15376/biores.11.1.1202-1213

Wei, D., Schmidt, O., and Liese, W. (2013). “Durability test of bamboo against fungi according to EN standards,” European Journal of Wood and Wood Products 71(5), 551-556. DOI: 10.1007/s00107-013-0707-2

White, D. G., and Childers, N. F. (1945) “Bamboo for controlling soil erosion,” Agronomy Journal 37(10), 839-847. DOI: 10.2134/agronj1945.00021962003700100007x

Xie, J., Qi, J., Hu, H., De Hoop, C. F., Xiao, H., Chen, Y., and Hse, C. (2019). “Effect of fertilisation on anatomical and physical mechanical properties of Neosinocalamus affnis bamboo,” Journal of Bioresource and Bioproducts 4(1), 67-72. DOI: 10.21967/jbb.v4i1.183

Xin, J., and Qion, L. (1983). “Preliminary observations on vascular bundles of bamboos native to China,” Journal of Sichuan Agricultural University 1(1), 68-70. DOI: 10.16036/j.issn.1000-2650.1983.01.010

Xu, G., Wang, L., Liu, J., and Wu, J. (2013). “FTIR and XPS analysis of the changes in bamboo chemical structure decayed by white-rot and brown-rot fungi,” Applied Surface Science 280, 799-805. DOI: 10.1016/j.apsusc.2013.05.065

Yang, X., Tian, G., Shang, L., Lv, H., Yang, S., and Lie, X. (2014). “Variation in the cell wall mechanical properties of Dendrocalamus farinosus bamboo by nanoindentation,” BioResources 9(2), 2289-2298. DOI: 10.15376/biores.9.2.2289-2298

Zhan, H., Tang, G. S., Wang, C. M., and Wang, S. H. (2015). “Chemical properties and fibre morphology of Fergesia Fungosa at different culm age and height,” BioResources 10(3), 5666-5676. DOI: 10.15376/biores.10.3.5666-5676

Zhan, H., Zhang, L. Y., Niu, Z. H., Wang, C. M., and Wang, S. G. (2016). “Chemical properties and fibre morphology of Dendrocalamus hamiltonii as potential pulp material,” European Journal of Wood and Wood Products 74(2), 273-276. DOI: 10.1007/s00107-015-0993-y

Zhang, Z., He, X., Hu, C., Zheng, F., Wang, P., and Jin, H. (1997). “Study on biological properties of PhytIostachys nigra,” Journal of Bamboo Research 16(1), 6-12.

Zhao, H., Wang, L., Dong, L., Sun, H., and Gao, Z. (2014). “Discovery and comparative profiling of microRNAs in representative monopodial bamboo (Phyllostachys edulis) and sympodial bamboo (Dendrocalamus latiflorus),” PLoS ONE 9(7), 1-3. DOI: 10.1371/journal.pone.0102375

Zheng, Y., Hong, W., and Zhang, W. (1998). “Study on age structure of high-yield both bamboo shoot and timber stand,” Scientia Silvae Sinicae 34(zk), 46-51.

Zhou, B. (1999). “Rule of shooting and height growth of Dendrocalamus latiflorus,” Forest Research 12(5), 461-466.

Zhou, B. Z., Fu, M., Xie, J. Z., Yang, X. S., and Li, Z. C. (2005). “Ecological function of bamboo forest: Research and application,” Journal of Forestry Research 16(2), 143-147. DOI: 10.1007/BF02857909

Article submitted: June 9, 2022; Peer review completed: November 30, 2022; Revisions received: April 18, 2023; Revisions accepted: April 24, 2023; Published: May 25, 2023.

DOI: 10.15376/biores.18.3.Hamid