灌木植物量测定技术的研究

本文对梭梭，柠条，毛条和花棒四种树冠具有代表性的旱生灌木植物量的测定技术进行了系统的分析和研究，结果表明：用传统的样方收获法测定这类灌木的植物量不具备实际的可行性，而数量化处理法，相对生长法和标准木法是测定这类植被植物量的理想方法，其中以数量化处理法效果最佳，相对生长法次之。     

国外紫花苜蓿引种栽培研究

引进美国、加拿大若干优良苜蓿品种，意在解决吉林省内苜蓿品种产草量偏低、种子质量差这一多年的问题，分别在吉林省长岭县、辽源市、四平市等立地条件及降水量不同的地带进行试验，选出最适宜在我省生长的WL232HQ，该品种的产量为国内主推品种的2．3倍。     

利用生物工程提高乳锌含量技术

文章利用生物转化工程原理将硫酸锌加入牛饲料间接强化牛乳进行了试验观察,效果转好。强化后牛乳无外观质量变化,乳锌经一个高峰期四周后处于稳定状态,其含量可满足婴幼儿生长发育的需要。同时,还提出了硫酸锌强化饲料的适量剂量。并就乳牛饲龄、胎次、体重、产乳期对乳锌的影响和强化方法进行了探讨分析。通过此项研究,为解决目前缨幼儿缺锌问题,开发了一个吸收率高、副作用小、安全可靠的补锌源。     

加快淮北地区杂交粳稻发展的几个问题

回顾了淮北地区十多年来杂交粳稻示范推广的发展过程，分析了影响杂交粳稻发展的主要原因，并论述了加快该地区杂交粳稻发展的几个主要问题。     

苎麻自交一代分离和变异的研究

1983～1985年以“黄壳早”、“芦竹青”、“古巴苎麻”和“武冈红皮种”为材料进行自交,并观测了自交一代的分离和变异情况,研究结果表明:a.根据自交一代的形态分类,可将“芦竹青”繁殖后代分为40个类型,“芦竹青”自交一代的麻骨颜色分离为四种,其分离比例为9.3:4.2:3:0.7,基本符合孟德尔遗传规律;b.个体间产量性状差异很大,株高变冥为0.23～1.68m,茎粗变异为0.48～1.14 cm,有效株变异为1～23株;c.40个类型的纤维细度的变异呈正态分布,变异为1168～1905公支,最细的类型和最粗的类型相差747支上述结果表明:苎麻自交后代的形态性状、产量性状和纤维细度均产生显著的分离和差异。     

佛甲草的栽培管理技术

概述了长沙地区栽培佛甲草的生物学特性及其可行的栽培技术和管理措施。     

黄瓜全雌性基因连锁的AFLP和SCAR分子标记

 本研究以全雌品种‘戴多星’自交系和弱雌品种‘北京截头’自交系为双亲杂交获得F₁ ,然后得到F₂ 性型分离群体, 利用分离群体分组分析法(Bulked Segregant Analysis, BSA) 构建全雌和弱雌两个基因池, 筛选了64对AFLP选择性引物EcoR I-NN +Mse I-NNN组合, 发现EcoR I-TG +Mse I-CAC引物组合在全雌基因池中扩增出一条分子量为234 bp的特异带。经F₂ 代单株验证, 该特异条带能在全雌单株中稳定出现。以MAP MAKER (Version 310) 软件分析, 该标记与全雌性位点的连锁距离在617 cM。命名该连锁标记为TG/CAC₂₃₄。将该特异条带回收、克隆、测序, 设计特异SCAR引物, 再对F₂ 代单株基因组DNA进行扩增, 仅在全雌单株中扩增出1条分子量为166 bp 的特异带, 表明已成功地将与黄瓜全雌性连锁的AFLP标记转化为操作简便、表现稳定的SCAR标记, 该标记命名为SA₁₆₆。     

Molecular genetics of behaviour: research strategies and perspectives for animal production

Genetic factors are undoubtedly involved in inter-individual variability of the behaviours that may be important for livestock production, as shown by pedigree studies, comparison of genetic stocks raised in the same environment, and selection experiments. The knowledge of gene polymorphisms responsible for genetic variability would increase the efficiency of selection, as shown for instance by the identification of the ryanodine receptor gene that harbours the mutations responsible for the porcine stress syndrome, that allows the eradication of the susceptibility allele. One strategy is to screen systematically the genes that are known to be involved in regulation of behaviour (functional candidate genes). This strategy is however very difficult for most behavioural traits, since behaviour is an emerging function from the whole brain/body and the molecular pathways involved in genetic variability are very poorly understood. Another strategy is to investigate linkage between trait variation and genetic markers in a segregating population (usually an intercross or backcross between two strains or breeds contrasting for the trait under study). It allows the detection of genomic regions influencing that trait (quantitative trait loci or QTL), and further investigation aims at the identification of the gene(s) located in each of these regions and the molecular polymorphisms involved in phenotypic variation. Although many QTL have been published for behavioural traits in experimental animals, very few examples are available where strong candidate genes have been identified. Further progress will be very much dependent upon the careful definition of behavioural traits to be studied (including their importance for animal production), on the reliability of their measurement in a large number of animals and on the efficient mastering of environmental factors of variability. The fast increase in the knowledge of genome sequence in several species will undoubtedly facilitate the application to farm animal species of the knowledge obtained in model organisms, as well as the use of model organisms to explore candidate genes detected by QTL studies in farm animals.     

柑橘抗CTV转基因与分子标记研究进展

综述了柑橘抗衰退病基因工程中两方面的研究进展。介绍多种来源于柑橘衰退病毒(Citrustriztezavirus,CTV)核酸序列的转基因柑橘和抗性种质资源中抗性基因的分子标记,以及所涉及的方法和遇到的问题。目前研究表明,虽然已成功实现对病毒衣壳蛋白(CP)等基因的转化和Ctv等抗性基因的标记,但尚未获得对CTV有高度抗性的转基因柑橘,而抗性基因亦不能实现定点克隆和转化。因此上述两方面研究还有待深入。     

Effects of winter wheat cultivars and seed rate on the biological characteristics of naturally occurring weed flora

Summary Differential competitive ability of six winter wheat cultivars and traits that confer such attributes were investigated for a range of seed rates in the presence or absence of weeds for a naturally occurring weed flora in two successive years in split-plot field experiments. Crop height and tillering capacity were considered suitable attributes for weed suppression, although competitiveness is a relative rather than an absolute characteristic. Maris Huntsman and Maris Widgeon were the most competitive cultivars whereas Fresco was the least competitive. Manipulation of seed rate was a more reliable factor than cultivar selection for enhancement of weed suppression, although competitiveness of cultivars Buster, Riband and Maris Widgeon was not enhanced by increased seed rate. Crop densities ranging between 125 and 270 plants m⁻² were found to offer adequate weed suppression. Linear relationships were observed between individual and total weed species dry weight and reproductive structures per unit area.