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101.
Genetic parameters were estimated for wood and growth traits in two 19-yr-old clonal trials and a 40-yr-old full-sib progeny trial of Norway spruce [Picea abies (L.) Karst.]. In the clonal trials high (>0.4) broad-sense heritabilities were found for wood density traits, lignin content, number of internal cracks, growth traits, spiral grain and number of resin canals. Moderate (0.2–0.4) heritabilities were found for tracheid lumen diameter and cell wall thickness, microfibril angle and tracheid length, while low heritabilities (<0.2) were found for pulp yield, fibre strength, wood stiffness and wood colour. Lignin content and pulp yield showed low genetic variation, whereas the genotypic coefficient of variation for most other traits ranged between 5 and 15%. Most traits showed low levels of genotype by environment interaction. Among the wood properties, latewood proportion, earlywood density and ring density showed significant, adverse correlations with volume in both clonal trials.  相似文献   
102.
The anatomy characteristics of cell wall and lignin distribution in different anatomical regions for 12-month-old bamboo species Pseudosasa amabilis was investigated.The lignin distribution was studied by means of optical microscope and confocal laser scanning microscope and the color reaction. In addition,the distribution of lignin in different tissues(fiber,parenchyma and vessel) was investigated by visible-light microspectrophotometry coupled with the Wiesner and Maule reaction.The cell walls of different tissues were all lignified and the lignin was widely distributed in different tissues, in which there was a difference between tissues and anatomical regions in lignin content.Guaiacyl lignin and syringyl lignin unit could be found in cell wall of fiber,parenchyma and vessel through Wiesner and Maule reaction and the absorbance peak of spectrum. There was no regular variation in lignin content with different radial location of culms and different location in fiber strands.The lamellation of the fiber cell wall was generally had as alternating broad and narrow layers with alternating low and high concentration of lignin.  相似文献   
103.
对世界范围内的木质素乙醇相关专利技术进行了深入分析,包括技术发展趋势分析、技术生命周期分析、申请人分析、国家技术实力分析、关键技术分类分析、同族分析,旨在通过专利分析洞悉木质素乙醇技术的整体发展态势,为本领域的技术创新和决策提供参考。  相似文献   
104.
ABSTRACT

The connection between chemical composition and anatomy of wood is poorly studied. Abiotic and biotic growth conditions affect the synthesis of structural compounds and the anatomy of wood at the same time as they affect growth. In this study, the wood chemical composition, and connections between wood chemistry and anatomy were studied in downy birch (Betula pubescens Ehrh.) grown on four growth sites possessing mineral and peat soils. Lignin, holocellulose, extractive and ash contents, and effective heating value were analysed and compared with libriform fibre double wall thickness and lumen diameter, vessel size and number, and ray and axial parenchyma numbers. Measured lignin and extractive contents were exceptionally high and holocellulose content low. Correlations between wood anatomy and effective heating value were partly different on different soils. Correlations between holocellulose and anatomy were the opposite of the correlations between other chemical compounds and anatomy. The significant correlations between chemical composition and anatomy were commonly opposite in trees grown on peat than in trees grown on mineral soil. Particularly, vessel characteristics and fibre wall thickness correlated significantly with wood chemistry in trees grown on mineral soil. The connections between wood anatomy and chemistry proved to be soil-dependent.  相似文献   
105.
The concentration of live fungal biomass (FDA mycelium) was investigated in seven chemically very different litter types, i.e. grey alder leaves, green and brown leaves of white birch, green and brown needles of both Scots pine and lodgepole pine. Concentration of FDA mycelium in the litters changed with the season, being low during the dry late summer and relatively higher during the more rainy, wet autumn. During autumns, when moisture was not limiting, lignin concentration and live fungal biomass were negatively related. It was concluded that the concentration of live fungal biomass in litter decreased linearly as the lignin concentration increased and thus also decreased linearly to decomposition level of the litter.  相似文献   
106.
The purpose of this study was to understand the variation in root litter mass‐loss rates in a climatic transect across a large region ranging from the Arctic Circle (66°N) in Scandinavia to Berlin (52°N) in north‐east Germany, dominated by coniferous monocultural forests. To investigate the combined influence of litter quality and climate, data were used from 37 sites and plots at which root litters of three coniferous species (Pinus sylvestris, Pinus contorta and Picea abies) had been incubated. In spite of the considerable climatic differences among sites, there were no strong relationships between any climatic variable and the lst‐yr mass loss (range 17.0–40.9%). For the lst‐yr mass loss, the average annual temperature was the most rate‐regulating factor for all litter combined, with a value for R 2 adj of 0.186. Substrate quality also had an influence. Thus, for the whole region lignin concentration was significant, with a value for R 2 adj of 0.142. For the separated groups of pine and spruce stands the value for r 2 increased but the factor average temperature still dominated and for pine the R 2 adj reached a value of 0.346. Over the region N concentration in the fresh pine root litter was significant (R2 adj = 0.232). For the root litter of P. abies the average temperature in July was the strongest rate‐regulating climatic factor, with a value for R 2 adj of 0.381. A combination of temperature in July and the initial P concentration in the litter gave an R 2 adj value of 0.713 for P. abies litter, thus explaining about 71% of the variation.  相似文献   
107.
通过向盆栽土壤中分别添加茅苍术(Atractylodes lancea (thunb) DC.)凋落物(CK)、内生真菌拟茎点霉(Phomopsis sp. 编号B3)和灭菌凋落物(MB)、内生真菌和凋落物(WB)、内生真菌和凋落物及菌体发酵液(WBF)、凋落物和灭菌发酵液 (WMF) 后,定期检测凋落物纤维素、木质素降解率,测定土壤纤维素酶和木质素酶活性,并利用巢式PCR方法跟踪土壤中活体内生真菌B3动态变化,研究了土壤施加内生真菌对掉落的茅苍术残体的分解及土壤降解酶活性影响。结果表明,植物内生真菌离开宿主进入土壤仍具有生理活性,能适应非宿主环境,存活30d之久。在此期间,内生真菌在富含凋落物的土壤中明显加快纤维素、木质素的降解,在10d、30d、60d取样测定,处理组中WBF和MB的土壤纤维素酶活性显著高于其他处理组,处理组MB和WB的土壤木质素酶活性显著高于其他处理组。  相似文献   
108.
《Plant Production Science》2013,16(3):278-282
Abstract

The relationship between chemical components of pod shell and pod dehiscence was investigated using 25 soybean cultivars; 16 with easily dehiscing pods (susceptible cultivars) and 9 with hardly dehiscing pods (resistant cultivars). After air-drying for about three weeks, the pod shells were ground and analyzed for the contents of neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), hemi-cellulose (HCe), cellulose (Ce), uronic acid and calcium. The correlation of the contents of chemical components with the percentage of pod dehiscence (%PD) was examined by principal component analysis. The first principal ingredient score was given by the formula; score = – 0.421[ADF] – 0.038[ADL] + 0.821[HCe] – 0.382[Ce] + 20.556, where, [ADF], [ADL], [HCe] and [Ce] are percentage of each component in dried pod shell. This score gave an eigenvalue of 30.2 and contribution rate of 97.1%, and the score was higher in the susceptible cultivars than in the resistant cultivars on the average. The multiple regression analysis of the relationship between %PD and the content of chemical components also showed that %PD was best predicted by the regression equation with two chemical components, [HCe] and [Ce]. Water retention capacity and cellulose crystallinity of the pod shell were less different between the susceptible and resistant cultivars. The results in this study suggested that the chemical analysis of dry pod shell may provide useful information on breeding and selection of the resistant cultivars.  相似文献   
109.
Leaf litter decomposition and nutrient release patterns from five common multipurpose tree species—viz., Artocarpus heterophyllus, Mangifera indica, Areca catechu, Citrus sp., and Tamarindus indica, found in homegardens of Mizoram—were evaluated using a litter bag technique. The result of the study indicates a varying pattern of decomposition and nutrient release (N&P) among the species. Citrus sp. and T. indica were found to be the most labile species with comparatively much higher decay constant and faster nutrient release. Initial nitrogen concentration, lignin content, and lignin/N ratio of foliage litter showed significantly higher (p < .01) correlation with the decay coefficient and were found to be the important determinants in the decay process. The initial slow release and immobilization of N in A. heterophyllus and M. indica leaf litter reflect their potential as a source of nitrogen storage and effective mulching material. While litter from T. indica and Citrus sp. can provide the short-term nutrient need, foliage for the other three species may supply the long-term nutrient requirement for the understory crops in such agroforestry systems.  相似文献   
110.
本试验旨在研究基于不同地区取样点土壤成分条件下,木质素降解菌的生长特性,并为筛选出降解农作物秸秆中木质素的优势菌奠定基础.通过对扬州、南京、临沂、潍坊和连云港地区5个取样点的土壤成分测定,并利用选择培养基和马铃薯葡萄糖琼脂(PDA)-RB亮蓝与PDA-Bavendamm平板显色反应鉴定不同土壤中木质素降解菌生长量及其木质素降解酶特性,依据各取样点菌株的生长特性最终选择优势菌株.结果表明,扬州取样点土壤中木质素降解菌密度[(5.67±0.58) 105g-1]极显著高于另外4个取样点(P<0.01),所获得的木质素降解菌的产酶特性亦优于其他取样点.可知,5个取样点土壤中木质素降解菌密度存在明显差异,并与土壤中总有机碳含量呈强正相关(r=0.84,P<0.01).  相似文献   
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