引进亚洲百合新品种的筛选

本研究以国外引进的11个亚洲百合品种为试验材料,通过箱式栽植将其种植在国家花卉工程中心温室内,并对植株生长高度、花蕾和花径大小等综合性状进行对比与分析,从中筛选出了适宜北京地区温室栽培的‘Black Out’、‘Cheops’和‘Navona’等3个百合切花品种以及名为‘Mount Duckling’的1个盆栽品种。本研究为亚洲百合新品种的筛选提供了一定的参考价值。     

浅析新时期我国农业推广中存在的问题及科学应对策略

依据我国新时期农业发展的优势环境展开了农业推广进程中普遍存在问题的深入分析,并针对目前农业发展中重科研、轻推广,机制建立不健全等现状制定了切实可行的应对策略,对促进我国农业的成果转化与合理推广有重要的实践意义。     

稻草与氨化稻草干物质采食量的模型化研究

本研究分别以稻草、氨化稻草为唯一能量和蛋白质来源,实测了山羊稻草、氨化稻草的干物质采食量(DMI),并借鉴现有成熟模型,建立了以稻草、氨化稻草的中性洗涤纤维(NDF)为预测因子的干物质采食量预测模型:DMI稻(g/d.kgMW)=30/NDF(%DM),DMI氨稻(g/d.kgMW)=39/NDF(%DM)。经验证,稻草、氨化稻草DMI预测模型的平均偏差(MD)分别为0.48g/d.kgMW与0.85g/d.kgMW,相应的平均预测方差(MSPE)为0.3599与1.0124。稻草与氨化稻草的MD、MSPE均很低,表明所建DMI预测模型精确可用。     

Parsimoniously modelling perennial vegetation suitability and identifying priority areas to support China's re-vegetation program in the Loess Plateau: Matching model complexity to data availability

The Chinese Central government's policy to re-vegetate large areas of the Loess Plateau is currently being rapidly implemented at the provincial, prefecture, county, township, and village levels of government. Managers at these five levels of government need access to information to assist them to plan the land use change prior to performing on-ground activities. To this end, the suitability of 38 predominately native species in the 113,000 km² Coarse Sandy Hilly Catchments (CSHC) has been mapped at a 100 m resolution. In this data-sparse region, this was achieved by using a five-variable spatial overlay approach as we were able to readily access the required environmental variables and rule-set defining the species’ requirements (or tolerances). As the rules did not consider optimal growth they were possibly ‘too inclusive’, so the spatial extent of areas suggested for re-planting was refined by defining ‘target areas’ for trees, shrubs and grasses based on precipitation, aspect, landform, and slope. In the land-use planning criteria developed here we suggest that hill-slopes and gullies with slopes greater than or equal to 15° (defined from a 100 m resolution DEM) be left for natural succession. Due to lateral flow of water, sediment and nutrients from these steep slope and gullies, further prioritising re-vegetation target areas to the zone adjacent to and down slope from these steep portions of the landscape reduces sediment entering the river network with a minimal decrease of regional stream flow. These two functions (mapping species suitability and locating where priority and target re-vegetation activities should be undertaken) are available at a 100 m resolution for the entire CSHC by accessing a bilingual decision support tool called ReVegIH (Re-Vegetation Impacts on Hydrology). Finally, an ecohydrological model was used to simulate changes in average annual stream flow originating from the CSHC based on implementing the ‘target’ and ‘priority’ area re-vegetation activities within the constraints of two land limits.     

茉莉酸诱导小麦抗病虫性初步研究

初步研究了茉莉酸诱导对小麦苗抗病虫能力的影响,结果显示,小麦在喷施茉莉酸后能够提高植株对麦长管蚜和小麦白粉病菌、小麦叶锈病菌的抵抗能力,可显著降低小麦白粉病、叶锈病的发病级别和病斑数量,对麦长管蚜则在体重和产仔数量上有显著的抑制作用。     

白头翁根不同提取物体外抑菌试验研究

白头翁为毛莨科多年生白头翁属植物白头翁Pulsatilla chinensis Bunge Regel 的根茎.始载于<神农本草经>,列为下品,是常用中药,具有清热解毒、凉血止痢、燥湿杀虫的功效.传统主要用于治疗细菌性痢疾、阿米巴痢疾等.现代研究认为白头翁除了抗菌和抗病原作用外,还具有提高机体免疫力、抑制巨噬细胞分泌IL-6、抗癌、抗炎、抗毒、止泻、镇静、镇痛、杀灭滴虫和球虫、抑制肠运动、抗内毒素血症等作用[1].     

六六六在生态环境中的行为特征与起用林丹的科学依据

本文根据80年代初中国生态环境中六六六的污染概况,特别是六六六各异构体在植物、动物样品中的残留水平,在土壤中的消解、被作物吸收和在食物链中生物浓缩的特     

氟苯尼考的研究应用进展

氟苯尼考（florfenicol）又称氟甲砜霉素，是美国先灵一葆雅公司于1988年研制成功的一种新型兽医专用氯霉素类广谱抗菌药，其化学名称为D（＋）-苏-1-对甲砜基苯基-2-二氯乙酰氮基-3-氟丙醇。它具有抗菌谱广、吸收良好、体内分布广、安全高效、耐药性发生率低等特点，对敏感菌所致的畜禽细菌性疾病治疗效果显著。目前，已在亚洲、欧洲、美洲等20多个国家上市，主要用于禽、猪、牛、鱼等疾病的治疗。我国现已通过该药的审批，生产的剂型有水针剂、溶液和散剂等。     

大鼠BDNF基因真核表达载体的构建

从23日龄大鼠脑组织中抽提总RNA,应用RT-PCR技术扩增脑源性神经营养因子(BDNF)基因片段,将此片段克隆入T载体,酶切反应鉴定。然后双酶切BDNF-T载体和空质粒pEGFP(N1),将所获目的片段和线性空载体用T4 DNA连接酶连接,构建真核表达载体pEGFP(N1)-BDNF,并进行酶切反应鉴定及DNA测序。序列测定的结果与GenBank比较,所克隆的BDNF基因从起始密码子ATG到终止密码子TAG全长共750 bp序列完全相同。结果表明成功构建真核表达载体pEGFP(N1)-BDNF,为进一步研究BDNF基因表达,神经系统疾病治疗和生物制药奠定基础。     

无籽西瓜枯萎病抗性的遗传分析

西瓜枯萎病（Fusarium oxysporum f．sp．niveum）是西瓜生产中的毁灭性病害，培育和应用抗病品种是防治此病害最经济有效的措施。我国自20世纪80年代开展西瓜抗枯萎病育种以来，已培育出一批抗病品种并在生产上推广应用，但主要集中于二倍体西瓜，在三倍体无籽西瓜育种方面几乎没有涉及，因此无籽西瓜生产中缺少抗枯萎病品种。生产上对无籽西瓜枯萎病的防治主要是采用嫁接，防病的效果也较为理想，但嫁接增加了生产成本而且还存在不亲和、果实品质降低等问题。目前无籽西瓜生产面积正在逐年扩大，适时开展无籽西瓜抗枯萎病育种是满足生产需要、有效防治病害的根本途径。本试验采用NCⅡ杂交设计配制了部分无籽西瓜组合，鉴定双亲及F1的枯萎病抗性并进行配合力分析，以初步了解无籽西瓜抗枯萎病组合双亲选配的一般规律。