不同地理来源MGIII组大豆品种生育期结构分析及E基因型鉴定

Characterization of Growth Period Structure and Identification of E Genes of MGIII Soybean Varieties from Different Geographic Regions

In 2014 and 2015, 60 Maturity Group (MG) III soybean varieties from different geographic regions were chosen to characterize the maturity-related traits and to identify the alleles of the maturity genes (E alleles) in these varieties. The MGIII soybean varieties shared the similar growth period but owned different growth period structure. The spring-sowing MGIII soybean varieties from Northern China and the US bloomed earlier (shorter VP) and exhibited lower R/V values than those from Yellow-Huai-Hai River Valley (YHH) and South China. Six combinations of E alleles were identified in the tested Chinese varieties, among them E1e2E3E4 and e1-asE2E3E4 were found to distribute in larger areas of different regions and cover more ecotypes than other four combinations. In contrast, the type of e1-asE2E3E4 was the only E allele combination in the eight US standard varieties, indicating that the Chinese MGIII varieties were more abundant in genetic variations for the maturity-related traits. By comparing the average effect of each E allele on the maturity-related traits in MGIII soybean varieties under different sowing dates, it was found that the varieties with more dominant E alleles showed longer VP, shorter RP and smaller R/V value. The effects of different E alleles on flowering time and maturity were different, and the effect of the dominant E alleles on spring- sowing soybeans was stronger than that on the summer-sowing ones. The agronomic traits for MGIII varieties from different regions were significantly different and that correlated with the growth period structure. The height of bottom pods of MGIII soybean varieties from Northern China was negatively correlated with R/V, while the number of pods per plant was positively correlated with R/V. Branch number, pod number per plant and 100-seed weight of YHH MGIII varieties were not correlated with R/V. The branch number of southern soybean varieties was significant negative correlated with the VP. These results provide a basis for the improvement of the growth period structure of soybean varieties and adaptability of soybeans to multiple environments.