Effect of Soil Sodicity on the Growth of Four Cultivars of Grape

Several growth parameters of Perlette, Beauty seedless, Deiight and Thompson seedless have been studied at 13, 22, 39 and 67 per cent exchangeable sodium (ESP). Bud bursting was delayed at 67 ESP only. Mortality of buds took place after 20–30 days of sprouting at the highest level of sodicity. Both shoot and root biomass production was affected adversly as ESP increased. Cultivar differences of ESP × cul-tivar interactions in respect of root or shoot biomass production, behaved differently in the cultivars studied. 50 per cent reduction in root dry weight happened at 51 ESP in Thompson seedless as compared to 27 in Perlette. However in terms of aerial growth Delight was comparatively more tolerant than Beauty seedless, Perlette and Thompson seedless. Thus indicating the possibility of evaluating various stocks-scionic combinations for scaling up sodicity tolerance of grapes. Tolerance seems to be related with K/Na ratio in the leaf and not with absolute contents of sodium. It appears that there was excessive transportation of K from roots to aerial parts for coping up with sodium toxicity until there was breakdown in its translocation mechanism.