Selection in M2 Generation of Black Soybean Using RAPD Markers Associated with Salt Tolerance

Abstract

The black soybean was mutagenized with gamma rays to increase the genetic variation in our previous article. In this paper, the
RAPD markers of black soybean in M2 generation were further analyzed. A total of 9 M2 genotypes were investigated for molecular variations. Furthermore, our PCR results demonstrated that the all markers, associated with salt tolerance, produced
different-sized fragments. RAPD analysis detected a total of 32 amplification products, among which 23 were found to be
polymorphic. Primer OPAA-01 produced the maximum number of bands (10), while the least number of bands (1) was recorded
for primer OPAA-03. The amplified DNA fragments ranged from 303 to 1,931 bp. The maximum polymorphism (100%) was
recorded for the primers OPAA-02 and OPAA-14, while the minimum polymorphism (0%) was produced by the primer OPAA-03.
Analysis of genetic relationship showed there were two groups in the coefficient of 0.55. The first group inluded Detam 3 Prida as
salt-sensitive black soybean cultivar and it is closely related with BSMG-160, BSMG-304, BSMG-256, BSMG-352, BSMG-400, BSMG-448, BSMG-496, and BSMG-592 genotypes, sequentially. The second group has only BSMG-208 genotype as an effective out-group. In conclusion, contruction of genetic relationships can be done using RAPD markers and the use of molecular markers will allow a quick selection. Together, our results indicated that, M2 generation showed molecular variations and the strong potential usage for further advances in black soybean breeding.