| Quality improvement has become a major goal of wheat breeding program in our country, and it gets more and more hard and important especially after china attending WTO.The research of molecular mechanism of wheat quality traits can provide with scientific basis and direction for breeding practice.In this study, 57 wheat cultivars in huanghuai region were analyse for it's quality traits of seed and content of total glutenin polymer (TGP) and glutenin macropolymer (GMP).The study has two aims. One is to find out the correlation between glutenin polymer's content and size distribution and quality traits, the other is to study the accumulation regularity of glutenin polymer in different quality wheat and to confirm the key factors which affect the form of quality traits in wheat.The major results are as follows:(1) There were seed hardness,protein content and SDS- sedimentation quality traits in 57 wheat cultivars in huanghuai region. Seed hardness and protein content had narrower variation, but SDS- sedimentation had wider variation. According to these three quality traits, the 57 wheat cultivars were classed three big groups.(2) The content of TGP and GMP changed from 3.63% to 8.38% and 0.95% to 3.63% respectively,and there variance cofficients were 19.68% and 26.94%.The result indicated that the content of TGP and GMP had a wider variation.Most of strong-gluten-type wheats had more content than weak-gluten-type wheats.(3) Using the multistacking (MS) SDS-PAGE, the results showed that the proportion of larger molecular SGP in strong-gluten-type wheats were more than that in weak-gluten-type wheats. At the same time, the proportion of smaller SGP in strong-gluten-type wheats were fewer than that in weak-gluten-type wheats.Therefore, it had nearly correlation between size distribution and bread-making quality in wheat.(4) This research studied the correlation and regression between seed hardness,SDS- sedimentation and four biochemical traits.The results showed that GMP% (X3),FP% (X1)influenced SDS- Sedimentation (YI), and its regression equation was Y1=6.396X1 + 6.430 X3 - 47.276. TGP% (X2) was the key biochemical trait influencing seed hardness, and its regression equation was Y2=2.050X2 + 42.947.(5) After analysing accumulation regularity of two strong-gluten-type wheats and two weak-gluten-type wheats from grain filling to maturation, the result indicated that larger molecular glutenin subunits of wheat appeared 12 days later after ablooming of wheat. The content of glutenin subunits got more and more while the day got longer and longer,and it reached maximum value after ablooming 42 days of wheats.But smaller molecular glutenin subunits formed later and accumulated quickly.In addition, the appearance time of larger molecular glutenin subunits in strong-gluten-type wheats was earlier than that in weak-gluten-type wheats.(6) Accumulate trend of TGP and GMP followed the rule of"rise-down-rise -down-rise /down"in grain filling to maturation. The later stage of the wheat filling to maturation was the kye time.In the end of the accumulation of seed, the content of TGP,GMP in strong-gluten-type wheats were more than that in weak-gluten-type wheats.(7) Using the MS-SDS-PAGE to study the molecular distribution of SGP in wheats filling to maturation,the result indicated that the proportion of larger molecular glutenin in strong-gluten-type wheats was higher than that in weak-gluten-type wheats,and the proportion of smaller molecular glutenin in strong-gluten-type wheats was lower than that in weak-gluten-type wheats.Secondly, the appearance time and accumulation speed of SGP in strong-gluten-type wheats was earlier and faster respectively than that in weak-gluten-type wheats.This study provided with scientific basis and direction for parents choice of breeding pr- actice and quality choice of offspring material in wheats of Huanghuai region. |
PDF Full Text Request