Responses of some genetically diverse lines of chick pea (Cicer arietinum L.) to salt

Abstract

The salt tolerance of three tolerant accessions of chick pea, CM 663, 10130 and 10572 and three sensitive accessions 10582, 12908 and 12909 selected at the germination and seedling stage was assessed at the adult stage using sand culture salinized with 0, 40 or 80 mol m^-3 NaCl. The two tolerant accessions, CM 663 and 10572 and one sensitive, 12908 showed consistent correlation between the degrees of salt tolerance at the early growth stages and adult stage as the former two produced significantly higher seed yield compared with the other accessions and the latter did not survive till seed setting in the salt treatments. By contrast 10130 which was found relatively salt tolerant at the two early growth stages could not survive in 40 mol m^-3 NaCl till seed setting. Similarly two sensitive accessions, 10582 and 12909 not only survived at the adult stage but produced some yield as well. On the basis of performance of the six accessions at three different stages, accessions CM 663 and 10572 can be categorised as relatively salt tolerant, 12908 as sensitive and 10130, 10582 and 12909 as moderately tolerant. The tolerant accession CM 663 had high Na⁺ and Cl^- in the leaves but maintained high K:Na ratios and high K⁺ versus Na⁺ selectivity. This accession had relatively low leaf osmotic potential which may be due to its high accumulation of Na⁺ and Cl^- in the leaves. By contrast the second tolerant accession 10572 had lowest Na⁺ and moderate Cl^- in the leaves.of all accessions but had highest K⁺ versus Na⁺ selectivity, although its leaf K:Na was intermediate. It had also relatively low osmotic potential which cannot be related to different ions determined in this study. The salt sensitive accession 12908 had high leaf Na⁺ and moderate Cl^- but had very low K:Na ratio (less than one) and K⁺ versus Na⁺ selectivity. The remaining accessions as a whole did not show any consistent pattern of uptake of different ions. The positive correlation between the degree of salt tolerance at different growth stages do exist in some accessions of chick pea examined in the present study, but for others in which no positive correlation was observed suggests that a combination of certain characters can be used as selection criterion for improving salt tolerance in chick pea.