Genetic Analysis And QTL Mapping For Heading Date On Wild Emmer Chromosome 3A

Wheat heading date is a very important agronomic trait which has a close relationship with wheat yield, quality, disease resistance, resistance to salt or drought. Researching the molecular basis of wheat heading and the growth period is a good way to improve the yield and quality of wheat population. The F2 population derived from three crosses(3AL×2BS, 3A×4A and 3AL×CS) were used for QTL analysis of heading date under three environments to screen QTLs that can be expressed stably.We accorded the genetic map and phenotypic variation in different environments to identify the major QTL. This research mainly included the following three aspects:1.To elucidate the genetic basis of the heading date, two F2 populations derived from three crosses were assessed in there continuous years from 2012 to 2014 in Linan,Zhejiang province. The heading date varied considerably among individuals in different environments. There is a transgressive segregation phenomenon in the populations.2.22 polymorphic loci from 68 SSR makers amplified in 3AL and CS were detected. The average percentage of polymorphic loci was 32.35%.We built three linkage maps of 3A chromosome using3AL×2BS population.The total length of 3A genetic linkage map was 72.90cM、104.00cM、106.01 c M respectively with an average distance of 3.31cM、4.73cM、4.81 cM. 13 polymorphics amplified in 2BS and CS were detected. We built two linkage maps of 2BS chromosome using 3AL × 2BS population.The total length of 2BS genetic linkage map was 61.58 cM with an average distance of4.74 cM and 69.99 cM with an average distance of 5.38 cM.3.CIM model is used to detect QTL in different environments. Three early QTLs of heading date,explaining 4.80~34.19% phenotypic variance and their additive effect were about 3.16~7.22, were detected on binC-3AL3(0.42) and 3AL5(0.78)-1.00. The Ppd-B1 between Xwmc154-Xwms429 was the putative late heading gene on 2BS. QHd-3AL-1 near centromere has large genetic effect in the condition of autumn-sown, however it become very small in the condition of spring-sown. There is no QTL detected in the F2 populations of 3AL×4AL and 3AL×CS...