Genetic Analysis Of Development Stability And Yield Traits In Wheat

Wheat is one of the most important food crops in the world,which feeds about one-third of the world's population.With the global climate change gradually intensifies,it is becoming increasingly urgent to explore the growth and development mechanism of wheat so that ensure grain production stably.In this study,the recombinant lines(RILs)population derived from a cross “Xinong1376 × Xiaoyan81” was researched.All the materials were planted in Yangling and Zhumadian during 2014-2017,and the sowing were duplicated twice and divided into two stages with 30 days interval.The wheat 90 K chip and STS makers(related to Vrn-1?Vrn-3?Ppd-D1)were used to detecting polymorphic sites by scanning the whole genome of the parents and RILs,and a high density genetic map was constructed.QTLs were identified using the composite interval mapping method.Analysis results are as follows:1.Totally 9847 polymorphic SNP makers were detected between the parents Xinong1376 and Xiaoyan 81.Only Vrn-A1 and Vrn-D1 were polymorphic in the all STS makers.The SNPs with high missing ratio(>20%)or segregation distortion(P<0.05)were discarded.Finally 5966 makers(5964 SNPs and Vrn-A1,Vrn-D1)were incorporated into the genetic linkage maps of the 21 chromosomes.The total genetic distance was 2972.7cM,and the average marker interval was 0.50 cM.The A genome was consisted of 2858 makers,covering 1448.03 cM,with the average interval distance 0.51cM;the B genome was consisted of 2617 makers,covering 1091.99 cM,with the average interval distance 0.41cM;the D genome was consisted of 491 makers,covering 432.75 cM,with the average interval distance 0.88 cM.2.The software QTL IciMapping 4.0 and its composite interval mapping method were applied to identify QTLs for wheat development and yield traits in different environments.As the result,35 QTLs were identified,which located on chromosomes 1A?2D?3A?3B?4A?4B?5A?5B?5D?6A?6D?7A?7D,and explaining 2.59%~13.77% of the phenotypic variance.In generally,a total of 11 QTLs associated with development traits were identified,and 8 of them stably expressed in two or more environments;24 QTLs associated with yield traits were identified,and 8 of them expressed stably.Among those expressed stably QTLs,there were 4 major effect QTLs which respectively controlled seeding phase,sterile spikelets,seedset ratio and grains per spike.What's more,4 QTLs showed pleiotropic effects,which could controlled different traits on the same loci..