Molecular characterization of maturity genes of soybean involved in photoperiod-insensitivity and long juvenility

In soybean, delayed sowing dates or lower latitudes causes premature flowering in soybean that reduces the vegetative period and thereby the yield. Molecular analysis of the six soybean genotypes viz . , photoperiod-insensitive (EC 390977 and MACS330); photoperiod-sensitive (KDS 726 and KDS 753) and long juvenile (DT 21 and AGS 25) was done in the present investigation. Six gene specific Cleaved Amplified Polymorphic Markers (CAPS) were used for identifying dysfunctional e3 and e4 mutant alleles responsible for photoperiod-insensitivity. Restriction digestion of the PCR products was observed only with e3-fs CAPS marker; while in rest five CAPS markers no such digestion was observed indicating for absence of the five non-mutant allelic forms ( e3-fs, e3-ns, e4-tsu , e4-oto , e4-kes and e4-kam ) in these six soybean genotypes. The long juvenile (LJ) trait was assessed by using tightly linked SSR ( Satt197 179 and Satt063 116 ) markers which were highly informative, distinguishing the long juvenile genotypes from rest four genotypes. These SSR markers can be used for MAS for transfer of LJ trait from LJ parents to those lacking this trait. To further analyze the sequence of J gene, five primer sets were designed to cover its entire 2827 bp coding region along with small intervening introns (while excluding a 1493 bp intron). DT21 specific polymorphisms were detected in both nucleotide and amino acid sequences. Five additional variations were shared by either or both photoperiod insensitive genotypes with LJ genotypes.