食用向日葵产量性状的遗传研究

以食葵不育系17-A26为母本、恢复系17-C19为父本,构建P₁、P₂、F₁、F₂、B₁和B₂ 6个世代群体,研究了产量相关性状盘径、单株总粒数、结实率、百粒重、粒长和粒宽的后代变异及遗传率。结果表明,6个性状均为数量性状,变异幅度排序为单株总粒数>粒长>盘径>结实率>百粒重>粒宽,狭义遗传率排序为百粒重>粒长>单株总粒数>粒宽>盘径>结实率。根据遗传进度结果,百粒重、粒长、单株总粒数和粒宽宜早代根据表型选择,盘径宜晚代选择,结实率宜晚代结合多环境联合选择。     

甜樱桃光合作用研究进展

作者综述了甜樱桃光合作用的基本特性,以及甜樱桃品种间的差异、叶片内部叶绿素含量、不同节位、不同冠层、环境条件(光照、温度、水分和空气)等内、外因素对甜樱桃光合作用的影响,并对今后甜樱桃光合作用研究进行了展望,旨为甜樱桃科研与生产提供参考。     

CO_2施肥对大棚油桃光合作用及产量品质的影响

棚内CO2 浓度日变化幅度远大于棚外 ;在天气晴好、光合旺盛、通风受阻时 ,棚内CO2 匮乏可成为光合作用的主要限制因子。在保护地条件下 ,油桃光合速率 (Pn)日变化由露地的双峰曲线变为三峰曲线 ,最大Pn比露地提前 2h ,在 8时左右出现 ;光合“午休”现象不明显 ;晴天棚内日平均Pn为 5 .97(CO2 ) μmol/m2 ·s,比露地降低17.2 5 %。棚内CO2 加富对油桃光合作用和产量、品质有重要影响 ,较大幅度地提高了上午 8时～ 12时之间的Pn和光能利用率 ,日平均Pn 6 .95 (CO2 ) μmol/m2 ·s ,比对照提高 2 5 .90 %。树体生长健壮 ,生物量 (未含果实 )增加 12 .4% ,比叶重增大 ,产量提高 19.80 % ,品质改善     

湖羊生长性状遗传参数的估测

对湖羊生长性状的表型参数和遗传参数的估测表明，性别对这些生长性状有极显著的影响，在遗传参数的估测中剔除性别的效应可提高估计的正确性。初生重、断奶重、三月龄重、六月龄重、周岁重和日增重等性状都属于高遗传力性状，遗传力分别为０．４１９０，０．３０４２．０．６０２３，０．６０７７，０．３９５６和０．６９４５．根据相关分析结果，为提高湖羊的生长速度和肉用性能，把日增重和三月龄重作为主要选择性状，预期可获得较好的效果     

Investigations on the Occurrence of Hereditary Diseases in the Danish Cattle Population 1989-1991

Agerholm, J.S., A. Basse and K. Christensen: Investigations on the occurrence of hereditary diseases in the Danish cattle population 1989-1991. Acta vet. scand. 1993, 34, 245-253.– The methods of the Danish Bovine Genetic Disease Programme are outlined, and the results obtained during the first 3 years in function are described. The most common disease reported was spinal muscular atrophy in calves of the Red Danish Dairy breed with 312 reports. Necropsy was performed on 162 cases, and spinal muscular atrophy was diagnosed in 82 of these. Bovine progressive degenerative mye-loencephalopathy, rectovaginal constriction, syndrome of arthrogryposis and palatoschisis, hereditary chondrodysplasia (2 different types), syndactylism, epitheliogenesis imperfecta, and osteogenesis imperfecta was diagnosed with 1 case each. Lethal trait A46 was diagnosed in 4 calves. Some of these diseases have not previously been described in Denmark, and epitheliogenesis imperfecta was for the first time diagnosed in the Hereford breed. Chromosome translocation 1/29 was detected in the Blonde d’Aquitaine (BAQ), Limousine, and Red Danish Dairy breed. The aberration occurred frequently in BAQ. Furthermore, a complex chromosome translocation t(l;8;9)(q45;ql3;q26) was detected in the Red Danish Dairy breed.     

用RAPD技术筛选中国荷斯坦牛产奶量性状遗传标记

选用320条10碱基随机引物在由36头高产（305d产奶量〉8500kg）和32头低产（305d产奶量〈5600kg）中国荷斯坦牛所组成的2个DNA池间进行RAPD-PCR扩增，从中筛选出稳定性好、带型清晰且在2个DNA池间有明显差异的RAPD引物24条。用筛选到的24条引物对所有个体进行PCR检测，得到了5个与奶牛产奶量性状相关的RAPD标记，并对其中4个进行了克隆测序和SCAR标记转化以及生物信息学分析。结果表明：SCAR标记yield—s139与产奶量密切相关，应用电子克隆方法已将该标记由921bp延伸到2141bp，经同源性比较发现，此标记对应于奶牛基因组中LINEs家族中的一个重复元件，推测该元件附近可能存在与产奶量性状相关的QTLs或主效基因。     

Variation in Doubled Haploid Plants of Wheat Obtained through Wheat (Triticum aestivum) × Maize (Zea mays) Crosses

Variation was investigated in 110 doubled haploid (DH) lines of wheat derived from wheat × maize crosses. Field observation revealed visible variations in 15 DH2 lines such as extreme dwarfism, low seed fertility, alteration of spike type and stripes. Six agronomic traits, i.e., heading date, spike number/ plant, culm length, spike length, seed fertility and grain weight were statistically analyzed in the DH2 and DH3 generations. Out of the 88 DH2 lines/DH3 groups, 26 %/64 % showed significant differences from the parental variety in the means of one or more traits. Ranges of the DH3 lines were larger than those of the DH2 lines, except for spike number/plant. Furthermore, analyses of variance within and between DH lines showed the presence of heterogeneity/heterozygosity in the DH2 lines/plants. These results indicated the occurrence of gametoclonal variation in the DH lines. It is considered that most of the variations detected were due to the colchicine treatment rather than to the 2,4-D treatment or in vitro culture.     

人工种植沙拐枣生长发育特性及营养动态的研究

沙拐枣属蓼科沙拐枣属多年生灌木，主要分布在我国的西北地区,本文就沙拐枣人工种植后的出苗状况，生长发育特性及不同生育期营养成分变化动态等进行了研究，为我国西部大开发生态治理工程中沙拐枣的大面积推广种植提供了指导。     

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.