Abstract: Maturity and its related traits are important for the yield, quality and adaptability of soybean [Glycine max (L.) Merr.]. Up to now, several major genes have been identified to control the flowering and maturity time in soybean. The understanding of the maturity gene effect under different photoperiods will facilitate the qualitative design of growth period traits in soybean variety development. In this study, 39 near-isogenic lines (NILs) derived from Clark and Harosoy were used to analyze the effects of 6 major maturity gene pairs including E1/e1, E2/e2, E3/e3, E4/e4, E5/e5, and E7/e7 on developmental periods of soybean. The re-sult showed that the dominant alleles tend to delay the flowering and maturity time in most of the genotypes studied. Gene effect was found to be dependent on the genetic background, and the dominant allele could strengthen the effect of other maturity genes, indicating that there were interactions between major genes. The major gene effects under long-day (LD) condition differed from those under short-day (SD). LD promoted the roles of dominant alleles and delayed the flowering and maturity while SD had the opposite effects. Additionally, the photoperiod effects were also varied in the developmental stages of soybean. E1 and E4 were sensitive to photoperiod before and after flowering respectively, whereas E3 was sensitive to photoperiod during both of the two stages.

Key words: Soybean, Near-isogenic lines, Maturity genes, Photoperiod