摘要
为探明甘蓝型油菜含油量和产量相关性状的遗传机理,利用Sollux/Gaoyou DH群体株系间随机交配构建了包括134个组合的永久F2群体(immortalized F2population)。采用QTL Network 2.0软件对含油量、千粒重和角果粒数进行了4个环境下的联合QTL定位,分析QTL的加性、显性以及相关的上位性效应。结果在7条连锁群上检测到控制上述3个性状相关QTL共8个。除qSWC6和qSPA2,1个含油量,4个千粒重和1个角果粒数QTL与多环境下SG-DH群体定位结果区间重叠,加性效应方向一致,效应值相仿;主效含油量QTL qOILA7和3个千粒重QTL qSWA7,qSWC2,qSWC4无显性效应;qSWC6兼具加性和显性效应,qSWC8加性为主,微效显性,显性效应均呈负向;但两个角果粒数QTL qSPA2和qSPA6除加性主效外,还存在正向显性效应;4对上位互作QTL中,除qOILA7,其余7个位点均只有微弱互作效应。并对qOILA7和qSWA7/qSWC8连锁标记辅助选育提高油菜含油量和千粒重的育种策略进行了探讨。结果表明:油菜种子含油量和千粒重性状的遗传控制体系以加性效应为主,F1代无杂种优势,因而欲提高杂交油菜种子含油量和增加千粒重,需要培育高含油量和大粒亲本材料;而控制角果粒数基因同时具有较强的加性和正向显性效应,利用F1杂交种可望获得超双亲的杂种优势。
In order to study the genetic mechanism of oil content and yield-related traits in B. nap~, an immortal- ized F2（designated as IF2 ） population （134 crosses） was generated by randomly permutated intermating of SG-DH lines. Phenotypic data were collected from four environments. Using updated SG-map and QTL Network 2.0 mapping program, the QTL analysis for oil content （ OIL）, 1000-seed weight （SW） and seeds per silique （SP） were conduc- ted. The genetic effects including additive, dominant and all related digenic epist.asis were estimated. The results showed that in total eight major QTL for three traits were identified in seven linkage groups. Except qSWC6 and qSPA2, one QTL for OIL, four for SW and one for SP were all located in the overlapped confidence intervals with that revealed by SG-DH population, showing similar additive effect and same effect direction. In the loci of qOILA7 and three of SW qSWA7,qSWC2 ,qSWC4, significant additive without dominant effects were found. While for qSWC6 and qSWCS, both additive and negative dominant effects were detected. However, two major QTL for SP （qSPA2 and qSPA6） showed positive dominant effects beside additive effects. Of eight loci corresponding to four pairs of digenic interactions, seven were marker loci without additive effects involved. The QTL-based selection for increasing oil content by flanking markers of qOILA7 and seed weight through linked markers with qSWAT/qSWC8 was discussed. The results showed that predominant additive effects were observed for QTL of oil content and lO00-seed weight, pre- dicting no heterosis of these two traits in F1 generation. Therefore, to increase the oil content and lO00-seed weight in rapeseed hybrids, the strategy was to breed two parents with high oil content and large seed size first. However, since seeds per silique demonstrated both additive and positively dominant effects, the performance which was better than two parents could be expected in hybrids and might contribute to yield heterosis of F1 hybrids.
出处
《浙江农业学报》
CSCD
北大核心
2013年第2期205-212,共8页
Acta Agriculturae Zhejiangensis
基金
国家基金面上项目(31171180)
浙江省基金重点项目(Z3100592)
浙江省重大专项(2011C12005)
关键词
甘蓝型油菜
永久F2群体
QTL
含油量
千粒重
角果粒数
Brassica napus L.
immortalized F2 population
QTL
oil content
1000-seed weight
seeds per silique
