| In order to detect the quality law and high molecular weight glutenin subunits compositions of F1 of hybrid wheat, 14 parents with different quality patterns was selected and 8 kinds of hybrid combinations was conducted as follows: strong-gluten×strong-gluten, strong-gluten×medium-gluten, strong-gluten×weak-gluten, medium-gluten×strong-gluten, medium-gluten×medium-gluten, weak-gluten×strong-gluten, weak-gluten×medium-gluten, weak-gluten×weak-gluten, and then quality of 8 types of F2 and high molecular weight glutenin subunits compositions of parents, F1 and F2 were determined. In the interim, 6 types of wheat with alloplasmic cytoplasms and 2 types of common wheat were selected and mutually bred in order to study the influence of alloplasmic cytoplasms on wheat seed protein content. This study aimed at providing theoretical base and technical assistance to conduct combination of high yield and good quality wheat and improve the quality using alloplasmic cytoplasms.It got the following results:1 Determination of the quality of F2 hybrid wheat showed that, in hybrid combinations of the same male parent with different female parents, the quality of combinations with strong-gluten female parent were more desirable than that with medium-gluten and weak-gluten female parents; in hybrid combinations of the same female parent with different male parents, the quality of combinations with strong-gluten, medium-gluten and weak-gluten male parents cannot be discriminated, indicting that female parent had a stronger role in quality improvement than male parent and female parent particularly took an important part in the seed quality improvement of F2. Therefore, female parent with desirable quality should be selected when mating combination was prepared.2 As for the performance of F2 HMW glutenin subunits, 1 and 5+10 subunits had stronger impact on protein, wet- gluten, dough stability time, development time and degree of softening than l and 2+12 subunits, so introduction of 5+10 subunits was of significance to the quality improvement of wheat.3 Comparison of glutenin subunits between parents and F1 of hybrid wheat showed that subunits co-dominance and deletion was observed in F1, moreover, deleted bands were subunits bands of male parents. It was suggested that female parent with elite subunit took an important role in quality improvement of hybrid wheat.4 Comparison of glutenin subunits between hybrid wheat parents and F2 showed that subunits composition of F2 was consistent with that of female parent. When F1 was planted, subunits appeared segregated, and because of the maternal inheritance of HMW-GS, subunits of female parent occupied a larger proportion, so progeny subunit was close to that of female parent. It was further proved that parent, particularly female parent, carrying elite subunit, could function necessarily to improve the quality of F2.5 As for the influence of alloplasmic cytoplasm on F1 protein content, orthogonal combinations with 6 types of alloplasmic cytoplasms as female parent, had strong positive effect on protein content compared with counter-junctions combinations, and the types of Ae.u-niaristata cytoplasm and Ae.bicornis cytoplasm had the strongest positive effect, more remarkable than that of other 4 types of nucleoplasm combinations. It was indicated that the types of alloplasmic cytoplasms had good interaction with different nuclear genotypes combinations in improvement of protein content, so the universal and special hererosis of nucleo-cytoplasmic interaction was present. It was showed that the two types of alloplasmic cytoplasms had high utilization value in improvement of protein content and development of sterile cytoplasms favorable to quality.6 The research of alloplasmic cytoplasm influence on HMW-GS of backcross offspring showed that subunits co-dominance was observed in seed. The improvement of protein content by alloplasmic cytoplasm types might be resulted from the interaction of different subunits at Glu-B loci. Therefore, not only remarkable interaction between cytoplasm and nucleolus improve the protein content, but the interaction of different HMW-GS.
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