白背毛木耳组织分离菌株栽培对比试验

通过出耳栽培试验,比较分析白背毛木耳菌株‘漳耳43-28’、06283与其组织分离菌株 Z43-28-1、Z06283的菌丝生长速度、生长势、抗污染能力、产量等,结果表明：分离菌株Z43-28-1、Z06283比出发菌株‘漳耳43-28’、06283栽培袋菌丝生长速度分别提高10.3％、13.5％,污染率分别降低11.48％、38.55％,产量分别提高6.2％、2.7％。应用组织分离可以达到较好的品种复壮效果。     

低循环风速下木材表层水分蒸发的试验研究

木材干燥过程中,介质循环速度是一个影响木材干燥的重要工艺参数.在木材各含水率阶段,通过试验分析研究不同介质循环速度对木材干燥速度的影响.结果表明,介质循环速度对干燥速度的影响显著,但其影响随木材含水率（MC）的降低而减弱.在低介质循环速度条件下,试件MC大于45％时,表现为木材干燥速度和木材含水率偏差（△MC）随循环风速的增加而增加,呈显著正相关关系;试件MC介于35％ ～ 45％之间时,正相关关系存在但不显著;试件MC小于35％时,干燥室内循环风速的大小不影响木材的干燥速度和木材含水率偏差（△MC）.对试件表层含水率分析,试件表层含水率大于25％时,试件表面循环风速对试件表层含水率的影响显著;试件表层含水率小于25％时,试件表面循环风速对试件表层含水率的影响很小,不同循环风速下试件表层含水率基本一样.     

建立相似林分样木因子回归模型推算采伐木蓄积

在安化县杉木人工林相似林分内设立样地,测量样地对角线上26株林木的地径、胸径和树高,用Excel软件建立地径与胸径、胸径与树高的回归模型,再测量采伐木地径,用回归模型预测采伐木的胸径和树高,推算采伐木蓄积量。同时,采用地径一元立木材积表法测算林木蓄积量,并与采伐作业设计的二元立木材积表法测算的林木蓄积量相比较。结果表明:采用建立相似林分样木因子回归模型推算采伐木蓄积量方法接近采伐作业设计的蓄积量。     

正交试验优化红豆杉硒多糖的提取

以恩施高硒地区的珍贵药用植物红豆杉为研究对象,以料液比、水浴浸提时间以及微波处理时间为试验因素设计正交试验,优化了红豆杉硒多糖的提取分离纯化工艺.通过硫酸苯酚法测定红豆杉中硒多糖的含量,采用原子荧光法测定硒多糖中硒的含量,并以SPSS统计软件对正交试验结果进行处理和分析.结果表明,3因素对硒多糖提取率影响大小为料液比＞微波处理时间＞水提时间,且红豆杉中硒多糖的最佳提取条件为料液比1∶80(W/V)、水浴浸提时间30 min、微波处理时间5 min.在此条件下,测得红豆杉中硒多糖含量为1.96％,硒多糖中硒含量为0.0555 μg/g.     

油茶籽粕提取物中抑菌活性物质的分离纯化研究

以油茶籽粕正丁醇萃取物为原料,通过大孔树脂柱层析、正相硅胶柱层析、高效液相色谱等分离纯化技术将较强抑菌活性的物质进行分离.结果表明,采用60％乙醇进行大孔树脂柱层析,然后以乙酸乙酯、甲醇、甲酸体积比分别为9∶1∶0.1、8∶2∶0.1、7∶3∶0.1进行正相硅胶梯度洗脱,以30％甲醇作流动相进行高效液相色谱纯化,油茶籽粕正丁醇萃取物能分离出纯度非常高的抑菌活性物质.     

东莞与邻近地区土沉香居群的叶形态 和遗传多样性分析

利用ISSR 技术分析了土沉香也Aquilaria sinensis（Lour.）Gilg.页4 居群的遗传多样性及遗传分化。应用9 条 引物从4 个居群共221 份样品中共扩增出105 个位点,其中多态性位点为104 个,多态位点百分率（PPB%）为 99.05%。等位基因数（Na）和有效等位基因数（Ne）分别为1.9905 和1.5854;Nei爷s 基因多样性指数（H）为0.3390, Shannon 信息指数（I）为0.5054,表明土沉香种内存在较丰富的遗传多样性。土沉香4 个居群总的遗传变异（Ht）为 0.3236,居群内的遗传变异（Hs）为0.2500,居群间的遗传分化系数（Gst）为0.2274,基因流（Nm）为1.6983。UPGMA 聚 类分析结果显示,电白居群和大岭山居群优先聚类,然后再与清溪居群聚类,而广西居群与其余3 个居群明显分离, 显示出较大的遗传分化;电白居群的大叶类群的分化大于小叶类群;东莞大岭山小叶类群与电白居群遗传相似性较 高,而大岭山大叶类群与清溪居群的遗传相似性较高。基于该研究结果,认为东莞大岭山居群部分来自清溪自然居 群,部分与电白居群来源相同,它们均来源于海南。     

Functional characterization of Farfantepenaeus californiensis, Litopenaeus vannamei and L. stylirostris haemocyte separated using density gradient centrifugation

Haemocytes from penaeid shrimp (Farfantepenaeus californiensis, Litopenaeus vannamei and L. stylirostris) were separated using a discontinuous Percoll gradient. Shrimp haemocytes were spontaneously adhered to glass, allowing slide preparations for staining and microscopic differential counting. Like other crustaceans, shrimp has three main populations differing in presence and size of cytoplasmic granules and each population seems to be biochemical or functionally compromised. Prophenoloxidase (proPO )activity was mainly located in large granules haemocytes (75%) while the small granules cells participate with 25%, but seem to be responsible for encapsulation. Haemocyte discrimination ability was tested using Sephadex? (Seph?), DEAE‐Seph? and CM‐Seph?. Only DEAE‐Seph? was encapsulated by shrimp haemocytes and provoked the release of proPO activating system, indicating the role of particle charge in the activation of shrimp immune response.     

基于WebGIS和条码技术的土壤空间信息管理系统

针对精准农业土壤肥力诊断的需要,基于条码技术和WebGIS构建了针对土壤样品采集、化验和存储以及分析数据的空间管理与发布的松耦合系统。该系统基于条码技术对土壤样品采集、化验及存储等流程进行管理,基于WebGIS进行空间数据管理和发布,同时,基于Web Service技术实现数据同步,较好地解决了分布式系统中异构数据库数据的同步问题。应用实践表明,系统的设计思想和架构符合精准农业信息获取、信息管理的需要,同时,在大规模土壤调查、土壤监测领域也具有良好应用前景。     

Microbial respiration activities related to sequentially separated, particulate and water-soluble organic matter fractions from arable and forest topsoils

This study aimed to reveal differences in the relevance of particulate as well as water-soluble organic matter (OM) fractions from topsoils to the easily biodegradable soil organic matter (SOM). We selected eight paired sites with quite different soil types and soil properties. For each of these sites, we took samples from adjacent arable and forest topsoils. Physically uncomplexed, macro-, and micro-aggregate-occluded organic particle, as well as water-soluble OM fractions were sequentially separated by a combination of electrostatic attraction, ultrasonic treatment, density separation, sieving, and water extraction. The easily biodegradable SOM of the topsoil samples was determined by measuring microbial respiration during a short-term incubation experiment (OC_R). The organic carbon (OC) contents separated by i) the physically uncomplexed water-soluble OM, ii) the macro-, and iii) the micro-aggregate-occluded organic particle as well as water-soluble OM fractions were significantly correlated with OC_R. The correlation coefficients vary between 0.54 and 0.65 suggesting differences in the relevance of these OM fractions to the easily biodegradable SOM. The strongest correlation to OC_R was detected for the OC content separated by the physically uncomplexed water-soluble OM indicating the most distinct relation to the easily biodegradable SOM. This was found to be independent from land use or soil properties.