Genetic Mechanisms Controlling Variation for Salinity Tolerance in Upland Cotton at Plant Maturity

The genetic basis of salt (NaCl) tolerance at maturity stage was examined in six accessions of Gossypium hirsutum L. at plant maturity. The six accessions were crossed in all possible combinations. The NaCl tolerance of 30 F(1) hybrids and their six parents were assessed at maturity level in the iron containers by subjecting to constant NaCl treatments i.e., 0, 17.5, and 20 dS/m salinity. Indices of salt tolerance (relative salt tolerance) were analyzed using diallel method. Both additive and dominance effects appeared to be important for the expression of variation under low and high salinity levels. Estimates of narrow sense heritabilities for salt tolerance were remarkable. This suggested that rapid improvement in (NaCl) tolerance in G. hirsutum using high selection pressures in the F(2) population may be made through selection and breeding. (C) 2010 Friends Science Publishers