Eeffect of seeds aging on genetic integrity in Pennisetum glaucum germplasm resources

To elucidate the germination rate of pearl millet (Pennisetum glaucum) germplasm resources, seeds were artificially aged at 45 ℃ and 99% relative humidity for 0, 4, 8, 12, 16, 20 and 24 h. After aging, they were analyzed for genetic integrity. The results showed that the germination rate, percentage of polymorphic bands (PPB), number of alleles (Na), effective number of alleles (Ne), Nei’s gene diversity index (H), and Shannon-Wiener’s information index (I) of the treated group were lower than 0 h (CK) and had a negative correlation with aging time, which indicated that the genetic integrity of aged seeds decreased compared with CK. Aged seeds were significantly different (P < 0.05) from CK regarding of PPB, Ne, H and I, when the germination rate went down to 68.23%, which indicated that the regeneration germination rate of P. glaucum was 68.23%. In conclusion, the germplasm resources of P. glaucum should be updated when the germination rate decreased to 68.23% and the genomic-SSR markers could be used to evaluate the effects of seed aging on genetic integrity for its high polymorphism, and low germination was a disadvantage for maintaining the genetic integrity of germplasm resources.