大豆苗期耐淹性的遗传与QTL分析

Inheritance and QTL Analysis of Submergence Tolerance at Seedling Stage in Soybean [Glycine max (L.) Merr.]

涝害是世界上许多国家的重大自然灾害。耐涝性可分为耐湿(渍)性和耐淹性。以科丰1号(高度耐淹)×南农1138-2(不耐淹)衍生的RIL群体(NJRIKY)为材料,以盆栽全淹条件下的存活率为耐淹性指标,采用主基因+多基因混合遗传模型分离分析法进行遗传分析,并利用WinQTL Cartographer Version 2.5程序的复合区间作图法(CIM)及多区间作图法(MIM)进行QTL定位。结果表明,两次试验的耐淹性均存在超亲变异,试验间、家系间以及试验与家系互作间的差异均极显著;NJRIKY大豆群体的耐淹性为3对等加性主基因遗传模型,主基因遗传率为42.40%;在QTL分析中,用CIM和MIM共同检测到3个耐淹QTL,分别位于A1、D1a和G连锁群上的Satt648~K418_2V、Satt531~A941V、Satt038~Satt275(B53B^Satt038)区间,表型贡献率为4.4%~7.6%。分离分析与QTL定位的结果相对一致,可相互印证。

Flooding is often a serious natural disaster in the word. Flooding tolerance has been recognized in two categories： tolerance to soil wateflogging and tolerance to submergence. The objective of the present study was to reveal the inheritance and then to map the QTLs of tolerance to submergence in soybean. The survival percentage of seedlings of the RIL population NJRIKY derived from Kefeng No.1 （highly tolerant） x Nannong 1138-2 （sensitive） was evaluated under completely submerged condition in a pot experiment. The results from segregation analysis under major gene plus polygene mixed inheritance model showed that submergence tolerance of soybean was dominated by three major genes with the heritability of 42.40% and no polygene detected. With composite interval mapping （CIM） and multiple interval mapping （MIM） under Win QTL Cartographer Version 2.5, three QTLs associated with submergence tolerance were identified, which located in Satt648-K418_2V, Satt531-A941V and Satt038-Satt275 （B53B-Satt038） on linkage groups A1, Dla and G, respectively, explaining 4.4-7.6% of the total phenotypic variation. The results from segregation analysis and QTL mapping appeared relatively consistent and could be verified each other.