QTL Mapping And Dynamic Genetic Analysison Main Agronomic Traits In Agropyron Gaertn.

Agropyron Gaertn.,the most widely distributed wheat relative,with the characteristics of high yield,stress resistance and wide adaptability,is a high-quality genetic resource for improving wheat crops and grass crops.Using of three sites of Langfang,Zhangjiakou and Qinhuangdao in Hebei as different environmental effects,a quantitative trait locus(QTL)analysis of the main agronomic traits and dynamic QTL mapping of plant height and tiller number in Agropyron Gaertn.were conducted in a CP(cross pollinated)hybrid population derived from a cross between Agropyron mongolicum Keng Z2098 and Agropyron cristatum(L.)Gaertn.Z1842,with a genetic map constructed by SNP,SSR and STS molecular markers.The mainly results are as follows.1.The main agronomic traits of Agropyron Gaertn.were surveyed in the three years(2016-2018)of Langfang,Zhangjiakou and Qinhuangdao in Hebei Province.It found that the same trait showed significant differences in different years and different environments,but the differences of the years was less than the difference of the environments.The dynamics survey of the plant height and tiller number in two years(2017,2018)at two sites(campus,farm)was done.It found that the growth and development of plant height and tiller number showed the growth characteristics of having a quick growth in the early development period while steady growth in the later period.The investigation and analysis of the agronomic traits of Agropyron Gaertn.in the flowering period of the Changli campus for two years(2017,2018)was done,it found that there were a significant or high significant correlation between traits.2.The parents,A.cristatum L.Z1842 and A.mongolicum Z2098,were screened for 164 pairs of SSR and STS primers designed and synthesized by our research group.Sixty-three pairs of polymorphic primers and 22 molecular markers successful typed for mapping were screened.The genetic map of Agropyron Gaertn.consisting of 66 markers was constructed by combining with existing typing 44 markers.The map was consisted of seven linkage groups with a total length of 1452.81 cM and theaverage map distance was 22.01 cM.3.The QTL mapping of the main agronomic traits in CP hybrid population of Agropyron Gaertn.at two years and three sites were investigated.In 2016,a total of89 QTLs and two major QTLs controlling 14 agronomic traits were found in three environments.In 2017,a total of 72 QTLs and a major QTL were found in three environments.In 2018,a total of 68 QTLs were found in three environments.Dynamic QTL mapping analysis for plant height was carried out,it found that 69 unconditional QTLs and 130 conditional QTLs were detected in four environments,and 37 QTLs were both unconditional QTL and conditional QTL.Dynamic QTL mapping analysis for tiller numbers was done,it found that 53 unconditional QTLs and 55 conditional QTLs were detected in two years,and these QTLs were distributed on six chromosomes except chromosome 7.The QTL mapping of eight agronomic traits at flowering stage at two years was conducted,which detected 50 QTLs with a larger genetic effect,fourteen QTL rich regions found mainly in chromosome 2.The traits at flowering stage had a correlation.The molecular genetic analysis of main agronomic traits and the QTL expression patterns of plant height and tiller number in different growth stages would provide a basis for further fine mapping of excellent characters in Agropyron Gaertn.,gene cloning and molecular marker-assisted breeding of wheat and grass crops.