Allelic Variation of Glu-A1,Glu-B1 and Glu-D1 in Chinese Released Wheat Varieties in the Last 50 Years

The high-molecular-weight glutenin subunit (HMW-GS) components from about 85 varieties were fractionated by SDS-PAGE, including 22 corner stone breeding parents, 45 varieties taking important role in Chinese wheat production and 18 varieties with good bread making quality. The 22 corner stone breeding lines carry either null ? or l(a) summits on Glu-Al loci. Five types are detected on Glu-Bl, which are 7 + 8(b), 7 + 9 ?, 14 + 15 (h), 17 + 18 (i), 6 + 8 (d). 7 + 8 and 7 + 9 are the two major types. Six types have been detected on Glu-Dl, which are 2 + 12 (a), 2 + 10 €, 5 + 10 (d), 4 + 10 (j), 4 + 12 ?, 2 + 11 (g). 2 + 12 and 2 + 11 are the two major types. In the corner stone breeding lines, early premium from American carries 5 + 10, St2422/464 from Italy carries the 14 + 15. In addition, two relatively essential varieties, Mara and Alondra carry 5 + 10. In the 45 commercialized varieties, sowed more than 666 000 ha (10 million mu) annually, only Yangmai 5 conveys the 5 + 10 on Glu-Dl, and Xiaoyan 6 and Yumai 7 carry the 14 + 15 on Glu-B1. Four varieties, Funo, Nongda 139, Zhengzhou 683 and Fan 6 convey the 17 + 18 on Glu-B1. The 18 bread wheat varieties recommended by the Ministry of Agriculture in 1992 could be classified into two groups, 5 + 10 and 14 + 15. Zhongzuo 8131 and its selections are the typical genotype of 5 + 10. Genes coding the two subunits are from either Yecora F-70 or IRN68-181. Xiaoyan 6 and its derivative varieties are the typical genotype of 14 + 15. The genes coding 17 + 18 subunits in Chinese varieties were derived from Funo or its selections. These results basically reflect allelic changes on Glu-1 in Chinese wheat varieties in the past 50 years. It is also proven that HMW-GS components may have great diversity between lines from the same cross, which causes great difference on baking quality.

Study on Selection of Wheat Varieties for Noodle Production in Hebei Province and Factors Affecting the Processing Quality

[Objectives]To screen out the specific wheat varieties for noodle production in Hebei Province and analyze the factors affecting the processing quality of noodle.[Methods]The quality characteristics of grains,flour and noodle of major medium gluten wheat varieties in Hebei Province were detected and analyzed.[Results]The sensory score of noodle is significantly positively correlated with wet gluten content of medium gluten wheat flour,and extensile length,cohesiveness,resilience,elasticity,gumminess,chewiness and extensile distance of TPA of noodle,and is significantly negatively correlated with softening degree.TPA of noodle can indirectly reflect sensory quality of noodle.[Conclusions]Han 7086,Xingmai 4,Liangxing 66,Shiyou 17,Heng 5229 and Liangxing 99 are suitable for producing high-quality noodle,and they can be used as noodle-specific varieties for promoting in Hebei Province.

Assessment of wheat variety distinctness using SSR markers

Assessment of variety distinctness is important for both the registration and the protection of particular variety. However, the current testing system, which assesses a range of morphological characters of each pair of varieties grown side-by-side, is time-consuming and is not suitable for the assessment of hundreds of samples. The objective of this study was to develop a procedure for the assessment of wheat variety distinctness using simple sequence repeat（SSR） markers. A comparison between the molecular and morphological profile of 797 varieties was made. On the basis of the comparison, pairs of varieties with a genetic similarity value（GSV） ≤90% were deemed to be distinct, accounting for ~85% of varieties assessed in wheat regional trials. For the remaining ~15% of varieties, GSVs between different varieties were 〉90%, among which ~35% were not distinct and the other ~65% were distinct. Therefore, if given a GSV〉90%, the pairs of varieties should be morphologically assessed in the field. To avoid any errors in the assessments, we proposed the elimination of contaminant plants from the sample before comparing the varietal genotypes, scoring of the genotype at each locus with a pair of allele numbers when constructing a molecular profile, and faithfully recording two alleles at a non-homozygous locus. To reduce the workload and cost, a three-grade markers comparison among varieties is suggested. In addition, 80 SSR markers and a technical procedure for assessment of wheat variety distinctness have been proposed. Based on the procedure, the distinctness assessment of ~85% of all wheat varieties is completed in our laboratory annually. Consequently, total field assessment has been reduced considerably.