Starch Property And Biochemical And Molecular Markers Of Waxy Protein In Bread Wheat

Starch properties are the important factors to determine noodle quality. 1D-SDS-PAGE eletrophoresis and molecular markers were employed to survey the Waxy proteins and Waxy genes in 312 winter wheat cultivars and lines from Chinese winter wheat and U.S.A. and Austrilia, 60 lines selected from the cross of Baihuomai and Norin 67 which was detected preliminarily to be waxy wheat with Iodine-dyeing-seed-section , 120 F2 plants from cross of Lu935031(Jimai19) and Yumai 47 . Amylose content and RVA properties were also recorded. The major results were presented below:1 The components of waxy protein subunits could be detected precisely by 1D-SDS-PAG Eelectro- phoresis. In total, 39 and 7 cultivars and lines with null Wx-B1 were presented in Chinese wheats and foreign cultivars respectively. Yunfengzao 101 and Zhongliang 93646 were detected with theWx- 4A local mutants. Totally 58 of 60 lines from the cross of Baihuomai and Norin 67 were real waxy wheats. 33 of 120 F2 plants derived from Jimai 19 and Yumai 47 were presented in null Wx-B1, sharing 27.1% of the total number, and agreed with the proportion of 1/4, and showed the inheritance of Waxy protein fitted to the Mendel's segretional law.2 4 molecular markers could be used to detect different Waxy genes. The primer 1 could amplify one diagnostic band of about 1160bp to the regular Wx-7A. The Primer 2 could amplify one diagnostic band of about 440bp to Wx-4A. The primer 3 could amplify one diagnostic band of about 940bp to Wx-7D, and 360bp to Wx-7D to Baihuomai null mutation. The primer 4 could amplify one diagnostic band of about 204bp to Wx-7D, and showed polymorphisms to Wx-7A for different cultivars and lines.3 Differences between waxy protein and molecular markers were observed. In total, there were differences for 81 cultivars or plants in 464 cultivars and lines in primer 1, sharing 17.6%, 49 in primer 2, sharing 10.6%; and 13 in primer 3, sharing 2.8% and 8 cultivars in primer 4 , sharing 1.7%.Significant variantions in starch properties were observed. The variance coefficient of peak viscosity, hold through, break down and final viscosity for Chinese wheat was 15.9%, 18.5%, 31.3%, and 14.9%, respectively. A very significant negative correlation was observed between amylose content and peak viscosity and break down, and a significant4 negative correlation was presented between amylose content and pasting temprature. The correlation coefficients were lower. The difference for peak viscosity and break down and final viscosity between 37 cultivars with null Wx-B1 and the others with normal subunits was at 1% significant level, and the difference for amylose content and the ratio of amylose to amylopectin between 37 cultivars null Wx-B1 and the others with normal subunits is at 5% significant level. Compared with good quality noodle wheats from U.S.A. and Austrilia, significant variation was observed in starch properties in Chinese wheats and the range for amylose content, peak viscosity, break down, final viscosity and setback was 23.1%~ 33.6%, 1151cp~ 3522cp, 192cp~1711cp, 849cp~3456cp and 464cp~ 1192cp, respectively. 5 Significant differences in RVA properties between waxy wheats and non-waxy wheats were observed. Peak viscosity and break down were higher than non-waxy wheats, but hold through, final viscosity, setback and peak time were clearly lower than non-waxy wheats, and the pasting time was similar to the parents...