夏大豆重组自交系群体NJRIMN开花期和株高QTL定位

Mapping QTL for Flowering Time and Plant Height in a Summer-sowing Soybean RIL Population NJRIMN

大豆开花期和株高是存在相关性的重要育种目标性状,但江淮夏大豆该性状研究相对较少。为进一步解析这2个相关性状的遗传基础,本研究以夏大豆重组自交系群体NJRIMN为试验材料,利用QTLNetwok 2. 1软件基于混合线性模型的复合区间作图法(MCIM)和Win QTLCart 2. 5软件的多性状复合区间作图法(MT-CIM),对该供试材料5个环境下开花期和株高性状进行QTL定位。研究结果表明利用MCIM法定位到8个开花期加性QTL,其中q FT-6-2和q FT-11-1存在显著的加性与环境互作效应;还定位到11对开花期上位性QTL,其与环境的互作均不显著。加性效应共解释了71. 30%的开花期表型变异,而上位性效应只占8. 88%。定位到6个株高加性QTL,其中qPH-6-1、qPH-12-1和qPH-19-2存在显著的加性与环境互作效应;还定位到4对株高上位性QTL,其中qPH-8-1和qPH-16-1存在显著的上位性与环境互作效应。加性效应共解释了41. 04%的株高表型变异,上位性效应可解释14. 45%的表型变异。共发现4个同时控制开花期和株高的QTL,其中位于6、10和19号染色体上的位点分别与E1、E2和Dt1基因位置重叠。

Flowering time and plant height of soybean are important target traits for soybean breeding with significant correla- tion. However, relatively less studies of the traits for summer-sowing soybeans in the region between lower Yangtze River and Huai river were conducted. Mapping QTLs for these two traits by using recombinant inbred line populations can provide deep knowledge for their genetic basis. QTL mapping for flowering time and plant height in NJRIMN was conducted by using Win- QTLCart2. 5 with multiple-trait composite interval mapping （MT-CIM） and mixed-model based composite interval mapping （MCIM） via QTLNetwok2. 1. The results showed that 8 additive QTLs for flowering time were detected by MCIM method, a- mong which qFT-6-2 and qFT-11-1 had significant additive and environmental interaction effects. Eleven pairs of epistatic QTLs were also mapped, but there was no significant interaction with environment. The additive effects totally explained 71.30% of the phenotypic variation for flowering time, while epistatic effects accounted for only 8.88%. Six additive QTLs for plant height were mapped, among which qPH-6-1, qPH-12-1 and qPH-19-2 had significant additive and environmentM in- teraction effects. Four pairs of epistatic QTLs were also mapped, and there were significant epistasis and environmental inter- action effects in the epistasis between qPH-8-1 and qPH-J6-1. The additive effects totally explained 41.04% of the phenotypic variation for flowering time, while epistatic effects accounted for 14.45%. Five QTLs simultaneously controlling flowering time and plant height were found, and the three QTLs on chromosome 6, 10 and 19 were overlapped with El, E2 and Dtl gene.