Analyze Of Wx Gene Effect On Dough Rheological Properties Using Wheat RIL Lines

The mutation at Wx-A1, Wx-B1 and Wx-D1 alleles of hexaploid wheats causes lack of Wx-A1, Wx-B1 and Wx-D1 proteins, the lack of some or all of the three Wx proteins usually give wheat quality great influence. Using a normal cultivar Gaocheng 8901 (carrying all Wx genes) and NuoMai 1 (null at three Wx alleles), we developed a population of recombinant inbred lines (RIL) using single-seed descent method. Wheat mutants carrying different Wx alleles were indentified using three pair DNA based primers, and the effect of different Wx protein on dough rhological properties were investigated using mixed linear model; Wx genes, HMW-GS and their interaction effect were also calculated, and the random effect were estimated in order to assist selection breeding. The main results were as follows:1. Identification of wheat mutants at the three Wx alleles in the RIL populationA total of 228 RIL F7 lines were obtained to investigate the presence or absence of different Wx proteins, among which 48 of wild types, 26 of Wx-A1 null, 32 of Wx-B1 null, 30 of Wx-D1 null, 28 of Wx-A1 and Wx-B1 null, 20 of Wx-A1 and Wx-D1 null, 28 of Wx-B1 and Wx-D1 null, and 16 of waxy lines with the three null alleles were examined.2. Effect of Wx genes on dough rhological properties in RIL lines8 conbination types of Wx genes have great infucence on dough extensograph and mixograph parameters: AB null and BD null type have significant negative effect on Max Resistance and Area, on Max Resistance, BD null has significant positive effect, waxy type have significant positive effect on Max Resistance and Area, but negative effect on Extensibility;As to mixograph parameters, there wasn't any signification were detected on Mixing Time, Peak line Width, Right of peak slope and Width at 8 min; and B null, D null, AB null, BD null and waxy types have positive or negative effect on Peak line height, AB null, BD null and waxy types have positive or negative effect on Mixograph Energy; These effects agree with the effect of each type on amylose content.3. Effect of Wx gene and HMW-GS interact on dough rhological properties in RIL linesCombination of glutein subunits null, 1 on Glu-A1and 2.2+12, 5+10 on Glu-D1 result in four types; Wx gene and HMW-GS are considered as sepratate factor, with the genetypic as levels, mixed linear model are used to predict all the effects; The result are: Wx genes have effect on Rmax,extensograph area and MPV; HMW-GS have a great contribution on Rmax, Extesibility, MT and mixogragh Energy, the subunits 1 and 5+10 have positive effect on Rmax, MT and Energy, 2.2+12 have negative effect on Extensibility; Interaction effect exists for Extensibility, MT, MPW and Energy, and AD null/1/5+10,B null/1/5+10,AD null/1/2.2+12 and BD null/null/2.2+12 have higher predict values.