Compositional and structural characteristics of residual biomass from tropical plantations

Many products and abundant wastes from tropical plantations, such as latex, palm oil, and coconut production due to replantation, are waiting effective utilization. Nonutilized tropical biomass — oil palm (Elaeis guneensis Jacq.), coconut (Cocos nucifera L.) coir dust and coir fiber, and rubber (Hevea brasiliensis) wood — were analyzed for chemical and structural characteristics of wall polysaccharides and lignin. Coconut coir dust is mostly composed of middle lamella and is separated from coir fiber, which is composed of secondary walls. These were supported by lignin content, and structural characteristics of wall polysaccharides and lignin. The chemical and spectroscopic characteristics of walls of rubber xylem were similar to those of typical temperate angiosperm woods. Oil palm frond was significantly rich in arabinoxylan, and numerous acetyl groups were substituted to the arabinoxylan. Lignin of oil palm frond and wall polysaccharides of coconut coir dust are substituted with hydroxybenzoic acids with ester and ether linkages. Some p-hydroxybenzoic acid substituted to the wall polymers of coconut coir dust would contribute to the formation of associations between polysaccharides and lignin. Based on the above results it is suggested that coconut coir fiber and rubber wood are suitable resources for chemical pulp production for paper-making, but oil palm frond is not.     

椰子树叶鞘纤维增强体的结构特征

利用傅立叶红外光谱分析、化学分析、Ｘ射线和差热分析等方法,分析和评价了椰子树叶鞘纤维在制备绿色复合材料的用作纤维增强体适应性。用电镜扫描的方法研究了经碱处理和未处理的纤维形态。FTIR光谱分析和化学分析结果表明,经碱处理的纤维中半纤维素含量降低;Ｘ射线衍射证实碱处理的纤维结晶度增加。碱处理的纤维热稳定性略有增加,且抗拉性能也有所增加。综合机械和其他物理性能,这种椰子树叶鞘纤维增强体适用于制作绿色复合材料。     

Phylogenetic and pathogenicity evaluation of the marasmioid fungus Marasmius palmivorus causing fruit bunch rot disease of oil palm

Marasmius palmivorus is a marasmioid fungal species that exhibits parasitic behaviour, although most marasmioids are rarely parasitic. The fungus has been reported to cause fruit bunch rot disease of oil palm and coconut, but only a few studies on its pathogenic behaviour are available, particularly on oil palm. Hence, there is a need to assess the ability of the fungus to act as a pathogen and to study its molecular evolution and taxonomy. Nine isolates of M. palmivorus were successfully isolated from basidiocarps and diseased fruitlets of oil palm collected from oil palm plantations and were morphologically characterized on potato dextrose agar (PDA) followed by molecular identification based on nucleotide sequence alignments of internal transcribed spacer (ITS) regions of ribosomal RNA (rRNA) gene clusters with sequences from GenBank. Koch's Postulates confirmed that M. palmivorus could infect oil palm fruitlets with symptoms similar to those observed for bunch rot disease. Molecular phylogenetic studies using nucleotide sequences of ITS and the nuclear ribosomal large subunit (nLSU) showed that isolates sharing the same phenotypic characteristics of Marasmius palmivorus and Marasmiellus palmivorus are monophyletic and share a common ancestor. The fungus has also been shown to be more closely related to the genus Marasmius than Marasmiellus; therefore, we support retention of the taxon name of the pathogen causing bunch rot disease of oil palm as Marasmius palmivorus.     

Using plant architectural models for estimation of radiation transfer in a coconut-based agroforestry system

Software modules have been developed to predict the radiative environment of plant stands consisting of computer 'mock-ups' of plants. The architecture of plants used for the computation of radiative characteristics was described at the level of individual organs and simulated according to botanical rules. Three-dimensional stochastic numeric mock-ups were computed for coconut (Cocos nucifera L.) and for cacao (Theobroma cacao L.) according to the 'AMAP' methodology. Then the numerical radiative models were applied to these 'virtual plants' to describe the radiative budgets of individual plant parts and entire plants. Modelled light transmission through virtual coconut canopies was in good agreement with field measurements for different treatments and management practices including palm ages, varieties, and planting densities. In a second stage, combining the computer models of coconuts and cacao in a multistrata system, the fraction of radiation that was transmitted through the coconut canopy and intercepted by cacao was sucessfully simulated. This revised version was published online in June 2006 with corrections to the Cover Date.     

Headspace solid‐phase microextraction gas chromatography–mass spectrometry for the detection of volatile organic compounds released from Ganoderma boninense and oil palm wood

Basal stem rot disease caused by the white‐rot fungus Ganoderma boninense is a major threat to the oil palm industry, and hence, the ability to detect infections at an early stage of development is desired. In this study, a headspace solid‐phase microextraction (HS‐SPME) method coupled with gas chromatography–mass spectrometry (GC‐MS) was employed to analyse the volatile organic compounds (VOCs) released from G. boninense cultures and infected oil palm wood. We examined VOCs released from three types of samples: G. boninense mycelium, oil palm wood and oil palm wood colonized by G. boninense. This preliminary study led to the tentative identification of 57 VOCs, including alcohols, alkanes, volatile acids, ketones, aldehydes, esters, sesquiterpenes and polycyclic aromatic hydrocarbon groups. Aliphatic compounds with eight‐carbon atoms, such as 1‐octen‐3‐ol, 3‐octanone, 1‐octanol and (E)‐2‐octenal, were the most abundant constituents of the Ganoderma samples, whereas furfural and hexanal were the major compounds detected in the oil palm wood samples. Chemometric analyses using cluster heat maps and principal component analyses were used to discriminate between the VOC profiles. The results indicated that the novel method described here could be used to detect Ganoderma disease and, more generally, for chemoecological studies of plant–pathogen interactions.     

Perennial crop-based agroforestry systems in Northeast Brazil

Land use systems in the Northeast Region of Brazil are dominated by large holdings and extensive cultivation of perennial crops such as cashew, coconut, carnauba wax palm, babaçu palm and so on. The common feature which links these crops is the silvopastoral system of livestock (chiefly cattle, sheep and donkeys) grazing under them. Agrosilvicultural systems involving cultivation of annual subsistence crops, and in some instances other perennials, in the stands of these perennial crops is also common. The paper presents the available information on the management, production, rate of growth, economic importance, etc. of these agroforestry systems involving cashew, coconut and carnauba palm. These systems are of considerable merit in the environmental, agricultural and socio-economic conditions of Northeast Brazil. However, practically no research nor even systematic data collection has been done on these so that there is an almost total lack of information on them. In order to improve the systems, they should be studied in detail and research undertaken on various components (crops, trees and livestock) individually as well as the system as a whole. Selection of suitable species of grass and other herbaceous crops, appropriate management techniques for both overstorey and understorey species in relation to the age of the overstorey species, optimal stocking rates of animals, etc. have to be determined so as to enable plantation owners and operators to realize the full potential of these systems.     

不同轻基质配方对油茶苗木生长的影响

以椰糠为基本原料,通过与泥炭土、菌渣和木屑按不同比例混合配置了10种轻基质配方,并从根、茎、叶三方面系统的研究这10种配方对岑软3号小苗嫁接苗生长的影响。研究结果表明：除配方6（椰糠：木屑：泥炭土,9∶3∶1）和7（椰糠：木屑：泥炭土,6∶3∶1）外,剩余8种配方都适合做岑软3号小苗嫁接苗的基质,其中配方1（椰糠：泥炭土,4∶1）对茎和叶生长的促进作用最为明显,配方3（椰糠：菌渣,3∶1）和4（椰糠：菌渣,2∶1）对根系生长有明显的促进作用。     

The role of vascular bundles on the mechanical properties of coconut palm wood

This study examines certain physical, mechanical, and anatomical characteristics of coconut palm wood. The results show a correlation between the anatomical characteristics and density as well as lengthwise compression. All properties (density, frequency of vascular bundles (VBs), and mechanical properties) increase with the transverse distance from the center of the trunk. The study also tests VBs from different radial sections of the coconut palm tree (Cocos nucifera) for diameter, ultimate tensile strength, and modulus of elasticity. The influence of the VBs on the overall properties of the wood is discussed.     

椰心叶甲生活习性初探

椰心叶甲是我国林业检疫性有害生物之一，其幼虫和成虫隐藏于棕榈科植物未展开的新叶或狭窄的夹缝中危害，危害部分仅仅限于最幼嫩的心叶部分，叶展开后才离去，严重时可使植株死亡。文章对该虫各个虫态的形态特征进行了描述，并对其生活习性进行了初步的研究，为其防治提供理论依据。     

Comparison of the surface properties of reused brazilwood (Caesalpinia echinata) and imbuia (Ocotea porosa) to peach palm (Bactris gasipaes) plantation-wood

This work deals with characterization of the wear behavior of woods obtained from agribusiness waste and from post-consume items. The main goal on this research is to generate data that could contribute to highlight the engineering performance of endangered wood species, and enhance reintroduction of these species to natural environment. Post-consume samples from Brazilwood (Caesalpinia echinata) and imbuia (Ocotea porosa), and also from the pseudo-stem of peach palm (Bactris gasipaes) were tested and their abrasion behavior was characterized both mechanically and morphologically. The results obtained showed that the wear rate of the tested materials was dependent of their density, and that the pseudo-wood obtained from peach palm has a performance similar to that of several commonly used woods.     

轻型木结构建筑台风荷载响应研究进展

主要介绍了国内外轻型木结构建筑台风荷载响应的相关研究。简述了台风对木结构建筑作用的分析与计算方法;详细介绍了佛罗里达国际大学风墙实验;概述了用于预测风致荷载响应的有限元数值模型建模技术的发展与模型的加载和验证方法;分析了建模方法对结构行为的影响。该文可为轻型木结构建筑的风工程学理论、材性研究及防台风的设计提供借鉴。     

竹下脚料制备吸附黄金用活性炭

以竹下脚料为原料,通过正交试验法制取不定形颗粒炭,经检测其强度好,碘吸附值高,优于LY/T1125-1993《提取黄金用颗粒活性炭》标准A类(椰壳原料)指标,可作为椰壳活性炭的替代品用于黄金吸附,为黄金生产提供了新的活性炭品种。     

Multiclass method for the determination of pesticides in stem of coconut palm using matrix solid-phase dispersion prior to liquid chromatography analysis

A method was developed using matrix solid-phase dispersion and liquid chromatography with ultraviolet diode array detection for the determination of bromopropylate, clofentezine, coumaphos, difenoxuron, diniconazole, fenvalerate, flumetralin, fluometuron, and teflubenzuron in the stem of coconut palm. The parameters evaluated included the type of sorbent (C₁₈-bonded silica, neutral alumina, silica gel, and Florisil) and the volume of the eluting solvent, acetonitrile. The best results were obtained using 0.25 g of stem, 1.0 g of neutral alumina as sorbent, and 5 mL of acetonitrile. The method was validated using stem samples spiked with pesticides at different concentration levels (0.01–10.0 µg mL^?1). Average recoveries (using three replicates) ranged from 70 to 91 %, with relative standard deviations between 1.6 and 10 %. Detection and quantification limits were in the ranges 0.01–0.05 and 0.05–0.2 µg g^?1, respectively.     

“山竹”台风对深圳前湾片区5个公园园林树木的影响

以深圳前湾片区5个公园中的50种园林树木为调查研究对象,选取6个风害受损特征指标,采用层次分析法和模糊综合评价法对园林树木进行风灾后抗风性的调研分析与评价。结果发现,园林树木风害受损率与树高、冠高、冠幅、根系状况、抗弯强度和支撑条件均呈极显著相关性,与顺纹抗压强度和病虫害情况呈显著相关性;新建项目中,抗风表型良好的园林树木多为小乔木,而抗风表现较差的多为存在树木“头重脚轻”现象的树木。最后,总结降低园林树木台风损害的对策和树木配置优化措施。     

Isolation of Xanthomonas campestris pv. populi from stem lesions on Salix matsudana X alba ‘Aokautere’ in New Zealand

A yellow-pigmented, Gram-negative, aerobic, salicin utilising bacterium-identified as Xanthomonas campestris pv. populi was isolated from one year old stems of S. matsudana X alba‘Aokautere’ willows exhibiting stem necrosis. Although the bacterium was isolated from necrotic stem tissue almost in pure culture it was not pathogenic to vigorously growing material of S. matsudana X alba‘Aokautere’ in field inoculations. Stress and predisposing climatic conditions during winter (frost, rain, wind, mild temperatures) are thought to have favoured the initial infections of this opportunistic pathogen. This disease is not considered serious.     

茂名市区椰心叶甲发生与防治初报

调查茂名市区棕榈科植物椰心叶甲的发生及为害,结果显示:受害率为64%,最严重的是椰子,受害率达80%。通过6种施药方式在其不同寄主上进行防治试验试验结果表明:以灌心和挂药效果最佳,平均杀虫效果高于90%,防治效果80%以上。     

The Potential of Oil and Sago Palm Trunk Wastes as Carbohydrate Resources

The carbohydrates content of the water soluble and water insoluble material of the oil and sago palm trunk waste were analysed. The sago palm trunk waste yielded higher water soluble content (17.4%) compared to the parenchymatous tissues and fibers of the oil palm trunk waste i.e. 3.3% and 5.4%, respectively, with less than 10% of neutral carbohydrates detected by cysteine sulphuric assay. However, hot water solubles of the sago palm trunk contained about 61.7% glucose. On the other hand, the acid hydrolysable carbohydrates of the water insoluble materials of both oil and sago palm trunk waste were found to be less than 50% of the total materials. The fibers and parenchyma of the oil palm trunk yielded only 31.9% and 23.6% hydrolysable sugars, respectively. Glucose was the major monosaccharide afforded by all samples of oil and sago palm waste. Received 26 November 1998     

Property gradients in oil palm trunk (<Emphasis Type="Italic">Elaeis guineensis</Emphasis>)

Since the structure of oil palm wood varies dramatically, the property gradients of oil palm wood within a trunk are of great interest. In this study, the physical (density, water uptake and swelling in the radial direction) and mechanical properties (bending modulus of elasticity and strength, compressive modulus of elasticity and strength in the direction parallel to the fiber, compressive strength in the direction perpendicular to the fiber and shear strength in the direction parallel to the fiber) of oil palm wood for a whole trunk were examined. The water uptake, compressive strength in the direction perpendicular to the fiber, shear strength in the direction parallel to the fiber, bending modulus of elasticity and strength and compressive modulus of elasticity and strength in the direction parallel to the fiber appeared to be independent of trunk height but tended to be related to the relative distance from surface or density by a single master curve. However, the swelling in the radial direction of the oil palm wood was not correlated with the relative distance from the surface, trunk height or density. Finally, property map of oil palm wood for a cross section at any height was prepared for practical use.     

5种化学杀虫剂防治椰心叶甲试验

对珠海市椰子树林发生的椰心叶甲，使用10％氯氰菊脂、48％乐斯本乳剂、16％虫线清乳剂、81％马拉松乳剂、90％敌百虫等5种化学杀虫剂，进行施药防治对比试验。结果显示：喷施10％氯氰菊酯乳剂0．67ml/L与48％乐斯本乳剂1ml/L的混合液、16％虫线清乳剂5ml/L，杀虫平均死亡率分别为94．2％和93．8％，降低林木受害程度的防治效果分别为76．81％和78．26％，显著高于其它药剂处理的效果。