豇豆胰蛋白酶抑制剂和硫氧还蛋白的融合表达和活性测定

采用融合蛋白表达技术，通过1个人工设计合成的柔性接头，将豇豆胰蛋白酶抑制剂(cowpea trypsin inhibitor,CpTI)基因与表达载体上的硫氧还蛋白(thioredoxin )基因连接，构建了融合表达载体。将表达载体转入大肠杆菌(Escherichia coli )GI724，通过色氨酸诱导获得高效表达，产物以可溶状态存在。活性测定显示，融合蛋白具有抑制胰蛋白酶的生物学活性。以大豆胰蛋白酶抑制剂为参照，将融合蛋白热处理后进行活性测定，发现它具有较好的热稳定性。将肠激酶(enterokinase)与融合蛋白在37 ℃作用16 h，可获得切掉thioredoxin的CpTI蛋白。活性测定显示，切除thioredoxin后CpTI的胰蛋白酶抑制活性比同样处理条件下的thioredoxin-CpTI明显下降，比活力仅为原来的80%，说明融合蛋白具有更高的稳定性。研究结果为thioredoxin-CpTI作为一种生物农药的应用奠定了基础。     

吉林省农业资源的综合评价

吉林省是农业大省，因此农业资源对农业生产，特别是对粮食生产具有决定性作用。运用定性分析和定量分析相结合的方法，对吉林省农业资源进行了综合评价，进而提出今后合理利用农业资源的对策。     

番茄内生链霉菌S5的分离及其除草活性

采用植物内生放线菌分离方法从健康番茄（Lycopersicon esculentum）根中分离纯化出58株内生放线菌，从中挑选部分代表性菌株进行代谢产物除草活性检测，发现编号为S5的菌株的代谢产物对小麦（Triticum aesfivum L．）和绿豆（Phaseolus radiatus L．）种子的发芽有强烈的抑制作用，但对发芽后的幼苗生长无明显影响。以百喜草（Paspalum notatum）和狗牙根（Cynodon dactylon）为实验对象，证明S5菌株的代谢产物的确能抑制草籽的发芽，该活性具有潜在的除草效能。经初步鉴定，S5菌株为淡紫灰链霉菌淡青变种（Streptomyces lavendulaevar．glaucescens）。发酵条件实验结果表明，S5菌株在1％葡萄糖和0．3％牛肉膏的S培养基中，以2％接种量在pH7．0和25℃摇床培养，可得到最强的抑制种子发芽的生物活性。     

黄土高原水土流失区森林资源价值核算

概述了目前常用的森林资源价值核算方法,较系统、全面地核算了黄土高原水土流失区森林资源环境价值(包括涵养水源价值、保育土壤价值、固碳制氧价值、景观游憩价值和净化环境污染价值)和实物价值(包括林地价值、林木和果品价值)的现值,并且分析了不同贴现率时森林资源价值的差异,指出基于可持续发展的需要,应取低贴现率进行森林资源价值核算。同时计算结果表明,森林资源环境价值是森林资源价值的主要部分,充分说明了森林环境价值的重要性,应该引起人们的高度重视。     

水资源管理与可持续发展

从当前国内外水资源状况的角度入手,分析了我国水资源利用管理上存在的主要问题,通过水资源和可持续发展的关系阐述了可持续水资源管理的概念和基本对策,并对未来可持续水资源管理提出了几点设想与建议.     

小麦/蚕豆间作体系中的氮节约效应及产量优势

通过田间小区试验,研究了小麦/蚕豆间作条件下作物的产量优势及不同施氮水平和种植方式中土壤硝酸盐累积。研究表明,间作可以提高作物单位面积复合产量,增产幅度在6%3～3%之间,不施氮处理间作小麦产量比单作增加达84%;间作和施氮对蚕豆产量没有显著影响。不同种植方式下土壤剖面中硝酸盐累积量趋势表现为蚕豆单作>小麦、蚕豆间作>小麦单作。不施氮、施氮量为20、406、0.kg/hm2条件下,种蚕豆的土壤硝酸盐累积量分别比种小麦的土壤增加了25.4、63.5、50.9、93.4.kg/hm2,间作降低了土壤中硝酸盐累积。小麦、蚕豆间作体系中的产量优势主要是种间氮营养生态位发生了分化,蚕豆通过固定空气氮而减少对土壤有效氮的吸收,把土壤中的有效氮节约供给与之相伴的作物小麦利用。     

Molecular characterization of emmer (Triticum dicoccon Schrank) Italian landraces

Emmer (Triticum dicoccon Schrank,2n = 4x = 28) is a hulled wheatspecies [more] widely spread in the Mediterranean basin. In Italy it survives as acrop in a few marginal areas and peculiar ecological niches in different regionsof central and southern Italy. A renewed interest has occurred during the lastdecade toward local varieties belonging to this species. As a matter of fact,local varieties have the highest genetic variation and adaptation to the naturaland anthropological environment from where they originated. Results on thegenetic diversity within and relationships among 11 Italian local varieties ofemmer as assessed with 17 RAPD marker loci are here reported. The proportion ofthe among-local variety genetic diversity was as high as 48% (G_ST =0.479). Thus, about 52% of the total variation was within population. Localvarieties of emmer proved to be formed by a variable number of lines geneticallydistinguishable from each other, and the vast majority of individuals overpopulations proved to be different multilocus genotypes. Landraces of emmer fromcentral and southern Italy showed distinctive molecular traits. In particular,local varieties classified as «Central Italy» types were characterized by a common set of RAPD marker alleles and proved to bedistinguishable from both the «Southern Italy» and the«Garfagnana» accessions. The overall results confirm the highvariability that can be found within landrace populations, underlining thevalues of landraces as an irreplaceable bank of genetically diversified andhighly co-adapted genotypes. Information for an appropriate insitu conservation and management of this valuable source of emmergermplasm is discussed.     

A forage grass and small grain legume plant collecting expedition in South East Poland, 1990

Summary The Plant Genetic Resources Unit (PGRU) of the Institute of Grassland and Environmental Research, Welsh Plant Breeding Station (IGER, WPBS), UK, and the Plant Genetic Resources Section of the Plant Breeding and Acclimatization Institute (PBAI), Poland, carried out a joint collecting expedition in Poland between 25 August and 7 September 1990. The expedition was unique in that it was the first time that vegetative sampling had been applied to the perennial forage grass and legume populations of south east Poland. The expedition focused on seminatural vegetation in agriculturally managed situations and detailed collection site data on management systems was obtained from landowners.Samples were collected from 62 sites. Vegetative collections of Lolium spp. (37 populations) and Trifolium spp. (56 populations), and seed collections of Festuca spp. (32 populations) were made by the IGER team (Table 2). The PBAI team made 59 separate seed collections, mainly of Leguminosae.The expedition covered four geographical subregions of south east Poland. (See Fig. 1). These were the Nizina Mazowiecka south of Warszawa, the Wyzyna Malopolska with the town of Kielce at its centre and the Beskidy Zachodnie and Beskidy Wschodnie regions of the Carpathian mountains.A diverse range of habitats was sampled covering a broad range of altitude agricultural management systems and ecological conditions. Polish agriculture is faced with the problems of a rapid orientation to a market economy and it is likely that the diverse range of habitats encoutered will be reduced as agricultural practices change. This will lead to genetic erosion of the unique forage grass and legume populations to be found in Poland.Abbreviations ECP/GR European Co-operative Programme on Crop Genetic Resources - IGER Institute of Grassland and Environmental Research - PBAI Plant Breeding and Acclimatization Institute - PGRU Plant Genetic Resources Unit - WPBS Welsh Plant Breeding Station     

基于分布式水文模型的水土保持水文水资源效应研究

 以往水土保持水文水资源效应研究所采取的方法均为水文法和水保法。由于这2种方法都不能系统地揭示水土保持对水循环影响的物理机制,并且采用的水资源评价口径只是单一的狭义水资源,使得研究成果不能真实反映水土保持的水文水资源效应。以狭义水资源和广义水资源为评价口径的基于物理机制的分布式水文模型则能克服水文法和水保法的严重弊端。评述分布式水文模型的研究进展;应用基于物理机制的分布式水文模型(WEP-L模型),以黄河流域的重点水土流失治理区——河口镇至龙门区间为例,对水土保持的水文水资源效应进行定量研究。结果表明:水土保持使广义水资源量增加72．6亿m3,增幅27．1％;使狭义水资源量减少9．0亿m3,减幅14．4％;使狭义水资源的构成发生了变化,即地表水资源量减小、不重复量和地下水资源量增加。     

宁南山区小流域雨水资源潜力与供需分析

根据宁南山区典型小流域土地利用现状和相关雨水集蓄资料,计算了彭阳王洼小流域雨水资源潜力,结合小流域节水农业发展规划,对雨水资源开发利用潜力及其供需关系进行了初步评价。结果表明:(1)示范区雨水资源最大理论潜力为7682598m3,就地利用、异地利用和叠加利用3种利用方式的比例分别为50.96%,7.16%和41.88%。(2)示范区雨水资源可实现潜力量为7164885m3,占全流域雨水资源理论潜力的93.26%。(3)目前示范区小流域的需水总量为3739352m3,仅占可实现供水量的52.19%,从示范区小流域雨水资源的可实现潜力来看,还有较大的开发利用潜力。(4)示范区小流域雨水资源利用评价结果表明小流域所制定的雨水利用规模对雨水资源的利用还很不充分,应适当地扩大雨水就地利用规模。