QTL Mapping For Grain Color And Its Correlation With Pre-harvest Sprouting Resistance In Wheat

Pre-harvest sprouting(PHS)significantly influences grain yield and quality in wheat.The grain color is closely related to pre-harvest sprouting resistance.It is useful to study on the molecular mechanism of grain color and its association with PHS resistance,which can provide important informations for developing white/amber-grained wheat varieties with PHS resistance.In this study,major QTLs for grain color and PHS resistance were identified using linkage analysis and association analysis,their effects on grain color and PHS resistance were evaluated,and then favorable alleles for decreasing grain color and increasing PHS resistance were explored.Moreover,the effects of candidate gene Tamyb10 on grain color and PHS resistance were evaluated using 258 Chinese mini-core collections and 163 lines derived from the cross of Jing411×Hongmangchun21.The main results are as follows:(1)The broad-sense heritability of wheat grain color was 82.4%,and a significantly positive correlation was detected between grain color and PHS resistance.(2)Association analysis indicated 18 MTAs for grain color and 21 MTAs for PHS resistance in 105 wheat varieties,and 3 MTAs were simultaneously associated with the two traits,and located on chromosomes 2BL(mag3425)、3BL(mag3356)and 7BL(wmc517).(3)A SLAF high-density genetic map and the SSR genetic map were construted using Jing411×Hongmangchun21 RILs population.Linkage analysis identified 20 QTLs associated with grain color and 17 QTLs related to PHS resistance.Of these,three loci were stably related to grain color on chromosomes 1B,5A and 5B,eg.Qgc-ahau.1B.la、Qgc-ahau.5A.1a、Qgc-ahau.5B.1b,band two loci were stably associated with PHS resistance on chromosomes 3D and 5A,eg.Qphs-ahau.3D.2a、Qphs-ahau.5A.2a.(4)A totalof 3 favorable alleles for reducing grain color and seed germination index was further explored,including barc80-106bp(1BL)>barc152-103bp(IDS)and wmc402-137bp(7BS).(5)The effect of Tamyb10-Al on grain color was more significant than that of Tamyb10-D1,but its effect on PHS resistance was lower than Tamyb10-D1.