利用选择导入系进行水稻耐低磷鉴定与 QTL 定位分析

摘要

选取我国当前生产上大面积推广应用的籼稻恢复系明恢86和蜀恢527作为轮回亲本,以籼稻品种爷驼崽为供体亲本构建了2个 BC2 F4群体,在河北廊坊田间正常土壤正常施肥(对照)、贫瘠土壤正常施肥和贫瘠土壤低磷胁迫这三种处理下进行产量及相关性状的表型评价.同时,在北京温室采用水培法进行苗期耐低磷鉴定.在廊坊检测到49个产量及相关性状主效 QTL,这些 QTL 对表型变异的贡献率为6．7％~16．5％；其中有25个(51．0％)QTL 的有利等位基因来自供体亲本爷驼崽.在北京检测到影响耐低磷相关性状(根长、根系干质量、根冠比、地上部分干质量和总干质量)的主效 QTL 48个,这些 QTL 对表型变异的贡献率为7．7％~16．6％；其中有21个(43．8％)QTL 的有利等位基因来自供体亲本爷驼崽.多达79•6％的 QTL 能在廊坊环境两个或两个以上处理下被检测到,特别是与每穗总粒数、结实率和千粒重有关的 QTL,不仅能稳定的表达,并且它们在不同处理下具有比较一致的效应.在检测到的所有 QTL 中,有8个染色体区段在两种环境的低磷胁迫条件下被同时检测到,其中与第12染色体 RM511(Bin12．4)紧密连锁的位点,同时控制每穗实粒数、每穗总粒数、根长、根系干质量、地上部分干质量和总干质量等6个性状.%Two BC2 F4 backcrossing populations were generated by using the two widely used elite indica restorers in China,Shuhui 527 and Minghui 86 as recurrent parents,the indica variety Yetuozai as donor.The grain yield and its related traits were evaluated under normal fertilizer application level in normal soil (as control)and in poor soil,low phosphorus stress conditions in poor soil in Langfang,Hebei Province.Meanwhile,the introgressed lines (ILs)of two populations were investigated at seedling stage using nutrient solution in the glasshouse in Beijing.A total of 49 main-effect QTLs underlying yield related traits were identified,the contribution of phenotypic variations ranged from 6.7%to 1 6.5 %.Of which,25 (5 1 .0%)QTLs had favorable alleles from donor parent.A total of 48 main-effect QTLs were identified for yield related traits,the contribution of phenotypic variations ranged from 7•7% to 1 6.6%.Of which,21 (43.8%)QTLs had favorable alleles from donor parent.About 79.6% of the QTLs can be detected repeatedly under two or more treatments,especially those QTLs associated with grain number per panicle,spikelet fertility and thousand grain weight which displayed consistent phenotypic effects.Among all detected QTLs, eight could be simultaneously identified across two environments.RM5 1 1 (Bin.12.4 )on chromosome 12 showed the most strong pleiotropism,simultaneously controlling filled grain weight,total grain weight per panicle,root length,dry weight of root,dry weight of shoot and total dry weight.