摘要：选用抗豆象品种 (系 )VC6 0 89A 6、VC1973A×V2 70 9 2、V2 80 2 ,与农艺性状优良的推广品种中绿 1号 (VC1973A)和中绿 2号 (VC2 917A系选 )作亲本 ,按照完全双列杂交试验设计 ,配置杂交组合。对 2 0个杂交组合后代f2 群体主要农艺性状及抗虫性分析 ,发现株高和抗虫性有超亲遗传现象 ,杂交优势明显 ;单株荚数普遍低于亲本 ,而单荚粒数略高于亲本 ,百粒重与亲本之间差异不明显。抗虫基因有抗性累加效应 ,3份抗虫材料的抗虫基因可能不在同一位点上。单株荚数是产量构成的主要因素 ,且遗传变异程度大与抗虫性相关性不紧密 ,在后代选择时 ,应以单株荚数为主攻目标 ,其次是株高、荚粒数、百粒重和抗虫性。初步认为从P1×P4、P1×P5、P2 ×P4、P4×P2 、P2 ×P5、P5×P2 和P5×P3 组合后代中选择效果明显。

摘要：本研究采用遗传模型预测的方法,探究玉米轴部性状的遗传机理,以期为育种家指明育种方向,提高育种效率。以fBHJ和MBUB两亲本组配的含390个家系的f2群体为材料,利用植物数量分离分析软件包中的f2单世代分析方法,对其穗轴长、粒长、穗轴粗、粒宽、穗轴重、百粒重、粒厚等7个轴部相关性状进行数量遗传分析、相关分析以及回归分析。结果表明,穗轴粗、粒长、粒宽3个性状最适遗传模型为A-0,即无主基因遗传;穗轴重和粒厚受2对主基因控制,主基因存在加性-显性-上位性,符合B-1模型;穗轴长和百粒重由1对主效基因控制,最适模型分别为A-1、A-3,各模型主基因遗传率介于28.37%~59.11%,其中百粒重性状的遗传率最大。各性状均与百粒重呈极显著正相关。百粒重(Y)对其他农艺性状的回归方程为Y=-57.126+0.176X1+3.069X2+2.890X3+5.108X4,拟合度为0.723。通径分析中粒宽的间接作用和粒长的直接作用表现最大。这一研究结果为玉米轴部性状的遗传解析提供了理论依据。

摘要：以自育的高抗玉米粗缩病自交系QR-001为母本、高感自交系QS-001为父本,配制了包含281个单株的f2分离群体为作图群体。选用在玉米基因组中均匀分布的1 028对SSR引物在双亲间进行多态性引物的筛选,共检测到110个可以鉴别f2群体各单株标记基因型的SSR多态性标记。借助QTL IciMapping Version 3.3软件构建了较好覆盖玉米10条染色体的分子标记连锁图谱,图谱总长度为1 343.2 cM,标记间平均距离为10.3 cM。其中1个分子标记(bnlg161)不与连锁群连锁。所建连锁群中有26.6%的SSR分子标记发生偏分离。该图谱的构建为玉米抗粗缩病QTL定位、分子标记辅助选择和分子设计抗病育种等研究奠定了基础。

摘要：With the development in spinning technology, the improvement of cotton fiber quality is becoming more and more important. The main objective of this research was to construct a high-density genetic linkage map to facilitate marker assisted selection for fiber quality traits in upland cotton (Gossypium hirsutum L.). A genetic linkage map comprising 421 loci and covering 3814.3 cM, accounting for approximately 73.35% of the cotton genome, was constructed using an f2 population derived from cross GX1135 (P 1 )×GX100-2 (P 2 ). forty-four of 49 linkage groups were assigned to the 26 chromosomes. fiber quality traits were investigated in f2 population sampled from individuals, and in f2:3 , and f2:4 generations sampled by lines from two sites and one respectively, and each followed a randomized complete block design with two replications. Thirty-nine quantitative trait loci were detected for five fiber quality traits with data from single environments (separate analysis each): 12 for fiber length, five for fiber uniformity, nine for fiber strength, seven for fiber elongation, and six for fiber micronaire, whereas 15 QTLs were found in combined analysis (data from means of different environments in f2:3 generation). Among these QTLs, qfL-chr5-2 and qfL-chr14-2 for fiber length were detected simultaneously in three generations (four environments) and verified further by combined analysis, and these QTLs should be useful for marker assisted selection to improve fiber quality in upland cotton.