Analysis Of Quality Characters Of New Wheat Varieties (Lines) In Sichuan

Wheat quality is one of the main objectives of wheat breeding in China. To evaluate the genetic potential of new wheat varieties (lines) in Sichuan, especially in quality breeding, main agrinomic traits and quality characterss of forty-nine new wheat varieties (lines) in Sichuan province were investigated. A-PAGE and SDS-PAGE were applied to detect their gliadin variations and high-molecular-weight glutenin combinations. The results are as following:1. The plant height of these genotypes ranged from 68.28 to 106.08, with the mean of 86.73. The 1000-grain weight ranged from 40.70~56.85g. with the mean of 49.11g. The spikelet numbers per spike were 18.60-26.20, with the mean of 21.17. The grains per spike varied from 53.40-101.20, averagely 67.70. On average the spike length was 10.75cm and the grains weight per plant was 20.78g. Low level of CVs(coefficients of variation) were observed, and the agrinomic performance of these genotypes were relatively stable.2. The protein contents of these genotypes were medium or low, averagely 12.97%. The average sedimentation values were 22.23ml. The content of wet gluten were 33.68%. The farinograph parameters were not fine, for example, on average the developing time was 2.01min, Stability time was 3.22min and the Farinograph quality number was 35.66. According to the main quality indexes, W7 accorded with the standard of high quality, strong gluten wheat, other 4 genotypes reached the standard of special, medium gluten wheat and 2 materials accorded with the standard of special, weak gluten wheat. The CVs of quality traits such as sedimentation value, developing time, stability time and Farinograph quality number were high, whereas that of water absorption was small.3. The correlation analysis results showed that kernel weight had negative correlation with other agronomic traits, and the plant height had positive correlation with the most agronomic traits. Protein content had significant positive correlation with sedimentation value, gluten content and water absorption, respectively. Sedimentation value had significant positive correlations with other quality traits. There were significant positive correlations between gluten index and Farinograph quality parameters. The correlations between quality traits and kernel weight, grains weight per plant indicated that the nutrition quality could be easily improved with high yield simultaneously. Spikelets per spike and grains per spike had positive correlations with most of the quality traits.4. It was found that there were higher genetic diversity on gliadin in Sichuan wheat,and 48 gliadin patterns were detected. A total of 38 gliadin bands with different relative mobility were observed, among which 35 bands (92.10%) were polymorphic. Eleven to 23 bands could be separated in each variety or advanced line. Fifteen of 49 varieties or lines (30.60%) have the allele GlidlB3.5. High level of genetic variation at Glu-1 locus was observed. Eleven subunit patterns were detected, resulting in 18 subunit combinations. There are four accessions which quality score was 10 , and they are excellent parent accessions in high quality breeding. Twenty-one varieties or lines carried 5+10 subunits and 3 varieties had 2 subunit. The frequency of 5+10 in these Sichuan wheat genotypes, subunit was relatively high, while the frequencies of good subunits and their combinations were still low, indicating that more HMW-GSs with good quality should be introduced and utilized in Sichuan wheat breeding program.