HERITABILITY OF NACL TOLERANCE IN GERMINATING ALFALFA SEEDS

The objective of this research was the development of salt tolerance in germinating alfalfa (M. sativa L.) seeds. Five cycles of mass selection for NaCl tolerance during seed germination were conducted in the cv. Mesa-Sirsa. Standard germination techniques were employed using blotter paper saturated with NaCl solutions of 5 different concentrations at a temperature of 26.degree. C. The osmotic potential of the NaCl solution needed to produce 1% seed germination decreased from -1.40 to -2.45 MPa [pascal] during the 5 cycles of selection. Germination at -1.30 MPa osmotic potential increased from 3% for the source population to 86% for the 5th cycle of selection. The broad sense heritability estimate for NaCl tolerance during seed germination, averaged over all cells of selection and 5 levels of osmotic potential, was 50%. Significant progress was made in the development of salt tolerance in germinating alfalfa.