Submitted to: Journal of Cereal Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/1/2010
Publication Date: 9/8/2010
Publication URL: hdl.handle.net/10113/45310
Citation: Chen, F., Zhang, F., Cheng, X., Morris, C.F., Xu, H., Dong, Z.D., Zhan, K., He, Z., Xia, X., Cui, D. 2010. Association of puroindoline b-2 variants with grain traits, yield components and flag leaf size in bread wheat (Triticum aestivum L.) varieties of Yellow and Huai Valley of China. Journal of Cereal Science 52:247-253. Interpretive Summary: Puroindoline a and b genes have a dramatic impact on grain hardness (kernel texture), a significant effect on quality characteristics, and may play a role in plant disease defense. In China, the wheat producing region of the Yellow and Huai Valleys, covering all of Henan and parts of Hebei, Shanxi, Shaanxi, Gansu, Anhui, Jiangsu, and Shandong Provinces, is the largest and most important wheat production zone, with 45% of the total harvested area and 48% of the total wheat production. Improvement of grain yield through better adaptation to target environments has historically been the major focus of most breeding programs in this area, whereas only recently have detailed molecular genetic strategies been considered for increasing grain yield. In this study, associations between Puroindoline D1 alleles and Puroindoline b-2 variants and grain hardness, other grain traits, grain yield components, and flag leaf size were reported. Varieties with the Pinb-B2v3 allele possessed more preferable grain yield traits than those of varieties with the Pinb-B2v2 allele. These results identify additional avenues for gaining a better understanding of the molecular genetic basis of wheat grain yield and yield improvement.
Technical Abstract: A total of 169 wheat (Triticum aestivum L.) varieties (landraces and cultivars) were used to asses the relationship between Puroindoline D1 alleles and Puroindoline b-B2 variants and grain hardness, other grain traits, grain yield components, and flag leaf size. Results indicated that the average SKCS hardness of Pinb-B2v3 varieties was significantly greater than that of Pinb-B2v2 varieties within the soft Puroindoline D1 haplotype sub-group. Conversely, no statistically significant difference was obtained for SKCS hardness between varieties with the Pinb-B2v2 vs. Pinb-B3v alleles within the two hard Puroindoline D1 haplotypes (Pinb-D1b and Pinb-D1p sub-groups). Therefore, the Puroindoline b-B2 gene may have a bigger impact on soft wheat varieties than hard. Across all varieties, thousand-kernel weight, grain weight per spike, grain diameter, grain number per spike, flag leaf width and area of Pinb-B2v3 varieties were significantly greater than those possessing Pinb-B2v2. These results indicated that the Pinb-B2v3 allele was associated with preferable grain yield traits compared to the Pinb-B2v2 allele in bread wheat. This study provides evocative information for better understanding the molecular and genetic basis of wheat grain yield and improvement.