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1.
Brix weight per stool (BW) of sugarcane is a complex trait, which is the final product of a combination of many components. Diallel cross experiments were conducted during a period of two years for BW and its five component traits, including stalk diameter (SD), stalk length (SL), stalk number (SN), stalk weight (SW), and brix scale (BS) of sugarcane. Phenotypic data of all the six traits were analyzed by mixed linear model and their phenotype variances were portioned into additive (A),dominance (D), additive×environment interaction (AE) and dominance×environment interaction (DE) effects, and the correlations of A, D, AE and DE effects between BW and its components were estimated. Conditional analysis was employed to investigate the contribution of the components traits to the variances of A, D, AE and DE effects of BW. It was observed that the heritabilities of BW were significantly attributed to A, D and DE by 23.9%, 30.9% and 28.5%, respectively. The variance of A effect for BW was significantly affected by SL, SN and BS by 25.3%, 93.7% and 17.4%, respectively. The variances of D and DE effects for BW were also significantly influenced by all the five components by 5.1%~85.5%. These determinants might be helpful in sugarcane breeding and provide valuable information for multiple-trait improvement of BW.  相似文献   
2.
The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits (fruit length and fruit perimeter) in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage (1-12 d after flowering) for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage (13-60 datter flowering). The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage.  相似文献   
3.
多对性状的遗传分析计算,往往是遗传学的难点之一,如果不能准确把握分析和计算的思路,往往会发生配子、基因型、表现型种类和数目计算的遗漏、混乱或错误,而在解决这些诸多问题的时候,乘法定律的灵活使用,会帮助解决多对性状的组合问题。  相似文献   
4.
蒋雪  梁旗 《生物学教学》2006,31(3):74-74
典型的常染色体显性遗传病系谱往往具备有共同的特点:①患者双亲之一患病,且多为杂合体;②患者同胞有1/2可能患病;③患者后代有1/2可能患病;④男女患病机会均等;⑤连续传递。而在分析系谱时,某些常染色体显性遗传病由于不同因素的影响,产生特殊性质,出现特殊表型,不符合上述系谱特点,属于常染色体显性遗传病特殊类型,它们具有各自不同的遗传学特点,现介绍3种。  相似文献   
5.
郭军英 《新高考》2008,(7):103-104
一、链孢霉简介 粗糙链孢霉(Neurospora crassa)属于真菌类中的子囊菌(Ascomycetes),它是遗传分析的好材料。它既有高等生物减数分裂的特点,又有低等生物的特点:  相似文献   
6.
利用RAPD技术,从248个随机寡核苷酸(10bp)中筛选出18个引物能在供试的Ⅱ优系杂交水稻及部分亲本间扩增出51条稳定性较好的多态性片段。其中有6个引物能在供试材料间稳定地扩增出19个强的多态性标记。利用这些标记能有效地区分各组合中不育系、保持系、恢复系和F1,并能看出各组合中不育系与保持系、不育系与恢复系、F1与亲本间的遗传关系。  相似文献   
7.
陆美琴  赵理清 《科技通报》1995,11(6):365-369
采用特矮大麦/早熟3号、特矮大麦/紫皮大麦、特矮大麦91-6411、91-6411/早熟3号4具杂交组合的P1、P2、F1、F2、B1、B2世代,研究了大麦抗赤霉病性的遗传,结果表明,大麦抗郝霉病性表现 部分显性或超显性,细胞质作用不明显,在特矮大麦/早熟3号、特矮大麦/紫大麦和特矮大麦/91-6411中,共同亲本特矮大感病性主要受一对隐性基因控制;在91-6411/早熟3号中,抗赤霉病性为数量性  相似文献   
8.
多发性双胞胎家系的遗传分析   总被引:2,自引:0,他引:2  
报道了3个多发性双胞胎家系,在这3个家系中有环境因素起主导作用的,有遗传因素起主导作用的,而这些因素都是通过母体发生效应的。  相似文献   
9.
短光敏不育系宜DS-1为新型生态型核两用不育系,本研究表明:其不育基因遗传较复杂,共有三对显性短光低温敏基因与两对隐性保持基因互补控制短光低温敏感核不育现象,与现有光温敏核两系不育基因间能相互恢复,且含有对WA-CMS与DA-CMS的强恢复基因。短光低温敏原始供体材料红粳是美国光身稻品种pecos。  相似文献   
10.
<正>自由组合定律计算题是很多高中学生在学习生物课程中遇到的"拦路虎",也是高考考查的重点和热点。由于自由组合定律涉及两对或多对相对性状的遗传分析,情况复杂,需要有  相似文献   
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