Physiological basis of differences in salinity tolerance of pigeonpea and its related wild species. uri icon

abstract

  • The physiological responses of a tolerant (ICPL227) and a sensitive (HY3C) pigeon pea genotype and of tolerant (Atylosia albicans, A. platycarpa and A. sericea) and sensitive (Rynchosia albiflora, Dunbaria ferruginea, A. goensis and A. acutifolia) wild relatives were examined over a range of salinity levels (0, 4, 6, 8 and 10 dS/m). Transpiration rate decreased with increasing salinity in tolerant and sensitive pigeon pea genotypes and there were no consistent differences between them in this respect. Although leaf proline concentrations increased under salinity in the cultivated pigeon pea and in some of the wild relatives, there was no relation between salinity tolerance and proline accumulation. The greater salinity tolerance of A. albicans, A. platycarpa and A. sericea was associated with efficient sodium and chloride regulation in the plant system. Shoot sodium concentrations of the tolerant wild species were 5 to 10 times less than those of the sensitive species, while root sodium concentrations in the tolerant species were 2 to 3 times higher than in the sensitive species. The potassium concentrations in the tolerant species increased with salinity, while in the sensitive species they decreased. Leaf magnesium concentrations remained unaffected with increasing salinity in the tolerant species, while in most of the sensitive species they decreased. Thus efficiency of regulation of ion transport to shoots seemed to explain the differences in salinity response among pigeon pea genotypes and related wild species

publication date

  • 1990
  • 1990