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81.
82.
种猪选育系统工程的若干问题研究 总被引:1,自引:0,他引:1
本文就种猪选育系统工程中的最优选配问题和饲料配方问题展开讨论,给出了系统建模,计算机仿真,数据库等技术的综合应用的研究结果. 相似文献
83.
南黄大麦系辐射突变选育而成。植株前期叶色浅黄,后期淡绿,是一种稀有的黄化型大麦。南黄大麦的发现,不仅丰富了大麦的基因库,而且在遗传、核质关系,超微结构、光合作用等方面具有理论和实践的意义。 相似文献
84.
Increasing the efficiency of water use by crops continues to escalate as a topic of concern because drought is a restrictive environmental factor for crop productivity worldwide.Greater yield per unit rainfall is one of the most important challenges in wa 相似文献
85.
戴陵江 《贵州大学学报(自然科学版)》1987,(2)
本文从染色体易位的发现开始,综述了国内外学者对植物染色体易位的研究进展。主要叙述了应用易位原理来进行育种研究以及其所取得的成果,从而说明易位不仅是一种染色体畸变现象,而且可作为一种研究手段,在对遗传学理论、生物进化、诱变育种等研究中都具有重要的价值。 相似文献
86.
87.
C. Gentsch M. Lichtsteiner H. Feer 《Cellular and molecular life sciences : CMLS》1991,47(10):998-1008
Paired groups of rats (derived from divergent, selective breeding or living in divergent environmental conditions) were compared with regard to locomotor activities. Intrapair differences were found to vary non-systematically, depending upon whether the rats were initially exposed to a test-environment with or without a slight environmental modification (reactive activities), or were allowed to habituate extensively to the environment (spontaneous activity). Since the behavioral patterns were found to represent distinct entities, this pointed to the necessity of differentiating clearly between spontaneous and reactive activities and indicated, once again, that both genetic and environmental influences are important in these behaviors and must be taken into account. Accepting and controlling for these variables makes it possible to use the factor of individual differences in laboratory animal behavior to advantage. 相似文献
88.
梅渠年 《首都师范大学学报(自然科学版)》1991,(1)
1977~1989年,我国按一雄配多雌,饲养雌性黑叶猴22头,共怀孕90胎,育成66仔,成活率达73%。母猴的发情无季节性,持续时间为2.57±0.68d,发情周期为22.5±7.93d。母猴因流产、早产、新生儿死亡、哺乳期夭折平均经75±27.42d后恢复发情交配。怀孕期为184±15d。胎盘属血绒膜型胎盘,重117.7±23.18g、脐长24.83±3.25cm,脐中段外径0.48±0.04cm,胎盘大18.38±2.76cm×7.25±1.2cm。在正常情况下,母猴的一个生殖周期为17.42±1.79个月。乳齿8d龄开始萌出;半岁长齐,20枚。2岁2个月龄至4岁为齿的更替期。4岁10个月龄后长齐,32枚,恒齿。仔猴4岁10月龄前平均月增重为115.69±51.02g。雌性3.96±0.53岁、雄性5.5~6岁性成熟。 相似文献
89.
Genetic and environmental influences on behavioral and neurochemical aspects of emotionality in rats
Summary Three pairings of rats (two derived from divergent, selective breeding and one from divergent environmental conditions) were compared with regard to behavioral and hormonal parameters. Striking differences were observed: results obtained in our own laboratory as well as those found in a review of the literature pointed to higher emotionality (e.g., increased defecation and corticosterone secretion, etc.) in Roman low-avoidance, Wistar-Kyoto and group-housed rats, as compared to their respective counterparts, Roman high-avoidance, spontaneously hypertensive, and individually housed Wistar rats. Concomitant receptor binding studies reviewed here (3H-diazepam- and3H-imipramine-binding sites) have revelaed, however, less consistent intrapair differences. 相似文献
90.
Most of the important agronomic traits in crops,such as yield and quality,are complex traits affected by multiple genes with gene × gene interaction as well as gene × environment interaction.Understanding the genetic architecture of complex traits is a long-term task for quantitative geneticists and plant breeders who wish to design efficient breeding programs.Conventionally,the genetic properties of traits can be revealed by partitioning the total variation into variation components caused by specific genetic effects.With recent advances in molecular genotyping and high-throughput technology,the unraveling of the genetic architecture of complex traits by analyzing quantitative trait locus (QTL) has become possible.The improvement of complex traits has also been achieved by pyramiding individual QTL.In this review,we describe some statistical methods for QTL mapping that can be used to analyze QTL × QTL interaction and QTL × environment interaction,and discuss their applications in crop breeding for complex traits. 相似文献