Studies On Genetical Law Of Quality Character In Hybrid Wheat

The study was mainly to investigate genetical law of quality character in hybrid wheat. 12 varieties with different quality types were selected as parents. 3 types of Different hybrid crosses were made according to strength of gluten content; 2 single crosses made in last year were selected and back-crossed with their parents; 4 male sterile types of alloplasmic wheat with Ae.kotschyi(K), Ae.ventricosa(Ven), Ae.bicornis(B), Ae.variabilis(V) cytoplasms were crossed with three restoring lines with good restoration performance. Quality characteristics of corresponding parents, hybrid F1, hybrid F2 and back-cross F1 were determined respectively. By heterosis analysis, correlation analysis, genetic variation analysis and principal component analysis, genetical law of quality character in hybrid wheat and influence of alloplasmic on seed quality were studied. The results were as follows:1. Heterosis of seed quality characters in F1 generation hybrid was significant, higher than that in p2 generation. There was higher heterosis of dough quality in F2 generation hybrid, which was very important for utilization of heterosis in wheat. It was easier to improve sedimentation value and wet gluten content than to improve protein content by utilization of heterosis. Cytoplasm has effect on quality characters, so it is well to select high quality parents as female when crosses were made.2. Correlation analysis illustrated: Provided the 2 traits(Hardness, Protein content) were used as selection criterions in early generations of quality improvement, it may be possible to acquire excellent varieties with high quality. By improving sedimentation value and protein content, it was possible to improve dough quality.3. Parent-offing correlation analysis illustrated: low-parent value shouldn't be neglected when selecting protein content of seed in early generations of hybrid; for improving Zeleny sedimentation value of hybrid F2 the key was to improve the value of high parent and mid-parent, while low-parent shouldn't be neglected. For most of seed quality characters, it was not ideal to estimate average level of hybrid F2 according to hybrid F1.4. Comparing the effect on hybrid wheat quality of 4 alien cytoplasms testified that the contribution of the 4 alien cytoplasms for wheat seed quality had no significant variance. It may be judged that this 4 alien cytoplasms have little negative effects when crosses are made.5. Principal component analysis illustrated: in the 8 characters analysed , sedimentation value, protein content, dough development time and stability time had the most contribution for wheat quality, so they have representative for wheat quality. So in the process of quality improving, the above quality characters can be selected as principal criterions, especially sedimentation value and protein content ,which are easily tested, should be used as priority.