N_(98s)×特青(亚种间杂交稻)抽穗后物质生产及分配特点研究初报

对N×特青示范田中试区与肥料试验田各处理小区稻株分析结果表明:抽穗后,亚种间杂交稻N×特青比常规稻特青干物质生产能力强,灌浆速度快;地上部各器官占植株干重比例,前者叶片比重大于茎,后者茎比重大于叶。亚种间杂交稻对肥料反应敏感,抽穗后,干物质累积,植株高度,每穗总粒数和粒重均随施肥量增加而增加,在高肥区有利于进一步提高产量,但增施氮肥后,灌浆速度明显滞后。     

二化螟群集性的调查研究

通过对二化螟群集性的调查分析,初步查明在不同类型田、水稻的不同生育期、二化螟幼虫的不同龄次,二化螟幼虫的群集性不同.这为科学制订二化螟防治指标提供了理论依据。     

农业产业化主体的困惑——个人理性与团体理性的冲突

龙头企业、中介服务机构和农户构成农业产业链条不可缺少的组成部分。任何一方对个人理性的盲目追求，会损害团体理性。因此，有必要对个人理性作适当的调整，以利于团体理性的发挥。     

七星瓢虫幼虫空间分布型及抽样技术研究

采用颍次分布X~2检验、Iwao平均拥挤度m~*=a+βx和Taylor幂法则S~2=am~b等8种方法,分析了七块麦田中七星瓢虫幼虫的空间分布型,认为其分布型为负二项分布,且聚集的原因是由于个体之间存在着相互吸引,并确定了代表性较强的棋盘式抽样技术,最佳抽样数量为:Q=28.7088/+0.7552。     

Imperfect Competition and Common Resource Exploitation—An Analysis of Renewable Resource Management with Non—use Values

This article analyzes the importance of non-use values in the management of natural resources with a model of imperfect competition.By constucting a framework of duopolistic exploiters.the incorporation of non-use values based on self-interest and altruistic motives appears to be significant for determining the degree of inefficiency caused by the problem of common property at the non-cooperative Nash equilibrium.It is found that when the non-use value placed by the altruist exploiter is bounded by that placed by the pure selfinterest exploiter,the effect of market power is dominated by the effect of common exploitation.In this case,the exploiters‘ harvesting strategy will response in the same direction to the change of each other‘s harvesting at the non-cooperative Nash equilibrium.In contrast,when the non-use value placed by the altruist is substantially larger or smaller than that placed by the self-interest exploiter,one exploiter‘s increase in harvesting will lead to a decrease in harvesting of the other exploiter at the non-cooperative Nash equilibrium.     

60日龄肉鹅发生小鹅瘟的诊治

吴川市板桥镇某养鹅专业户饲养的一群肉鹅，６０日龄时发生一种以下痢、脱水死亡为特征、伴有阵发性抽搐及扭头神经症状的疫病。经诊断检查，确诊为小鹅瘟病，现将诊治情况报告如下：１发病情况２０００年４月１９日，该专业户共购进雏鹅１８７只，１日龄时注射抗小鹅瘟血清，每只鹅１ｍＬ，育雏期间共死亡３只，尚余１８４只。养至６月１８日时发现病鹅１只，２０日病鹅发展到５只，并出现死鹅１只。至２２日时共发病１０只，死亡５只。发病期间，鹅主曾用土霉素、青霉素、禽菌灵等多种抗菌药物进行治疗，但效果均不理想。２　临床症状　病…     

Antibody directed against Marek's disease-associated tumor surface antigen can be eluted from Marek's disease tumor cells.

Antibody directed against Marek's disease-associated tumor surface antigen (MATSA) was eluted from tumor cells of lymphomas and peripheral blood lymphocytes that were isolated from Marek's disease virus-infected chickens. Feather follicular Marek's disease virus (MDV) antigen could not be demonstrated with this antibody by indirect immunofluorescent (IF) staining. Monoclonal antibody directed against MATSA could completely block the activity of eluted antibody and vice versa. By indirect IF staining using eluted antibody and fluorescein isothiocyanate (FITC) labelled antichicken globulin conjugate. MATSA-bearing cells were detected in MDV infected and herpes virus of turkey (HVT) vaccinated birds. Blocking of immunoglobulin molecules present on B-cells by anti-chicken globulin is critical in this test.     

亚麻工艺长相关性状的通径分析

本试验以6个普通亚麻品种为材料,进行工艺长相关性状的通径分析。结果表明,5个相关性状对工艺长度影响大小顺序为:单株粒重>单株粒数>千粒重>株高>主茎分枝数。降低单株粒重是提高工艺长度的主要途径。在千粒重、单株粒重相对稳定的类型中,选择植株较高、单株粒数较多者,或在株高、单株粒数相对稳定的类型中,选择千粒重较高者是提高工艺长度的重要途径。减少主茎分枝数亦可有效提高工艺长度,但作用较小。     

植物叶面铺展剂的复配规律Ⅰ.SDS和TX100混合水溶液体相及表面层相互作用行为

2种典型固体表面铺展剂SDS和TX100混合水溶液,无论在其表面层或在混合胶团中两组分之间均存在一定程度的相互作用,使得以廉价的SDS为主的溶液中加入少许TX100组成的复配体系表面活性提高,在植物叶面上的润湿性能改善,并从理论上计算了其相互作用参数,初步解释了实验现象,上述结果不仅对指导优良植物叶面铺展剂配方具有指导意义,也预示了潜在的实用价值.