摘要: |
The time to flowering and maturity are ecologically and agronomically important traits for soybean landrace and cultivar adaptation. As a typical short-day crop, long day conditions in the high-latitude regions require soybean cultivars with photoperiod insensitivity that can mature before frost. Although the molecular basis of four majorEloci (E1toE4) have been deciphered, it is not quite clear whether, or to what degree, genetic variation and the expression level of the fourEgenes are associated with the time to flowering and maturity of soybean cultivars. In this study, we genotyped 180 cultivars atE1toE4genes, meanwhile, the time to flowering and maturity of those cultivars were investigated at six geographic locations in China from 2011 to 2012 and further confirmed in 2013. The percentages of recessive alleles atE1,E2,E3andE4loci were 38.34%, 84.45%, 36.33%, and 7.20%, respectively. Statistical analysis showed that allelic variations at each of four loci had a significant effect on flowering time as well as maturity. We classified the 180 cultivars into eight genotypic groups based on allelic variations of the four majorEloci. The genetic group of e1-nf representing dysfunctional alleles at theE1locus flowered earliest in all the geographic locations. In contrast, cultivars in the E1E2E3E4 group originated from the southern areas flowered very late or did not flower before frost at high latitude locations. The transcriptional abundance of functionalE1gene was significantly associated with flowering time. However, the ranges of time to flowering and maturity were quite large within some genotypic groups, implying the presence of some other unknown genetic factors that are involved in control of flowering time or maturity. Known genes (e.g.E3andE4) and other unknown factors may function, at least partially, through regulation of the expression of theE1gene. |