THE EFFECTS OF DROUGHT STRESS AND ZEOLITES ON MORPHO -PHYSIOLOGICAL TRAITS OF Lathyrus sativus L. (GRASS PEA)

The objective of this study was to determine the effect of different rates of zeolites and drought stress on some Morpho-Physiological traits in Lathyrus sativus. Factors were considered as two levels of irrigation (irrigation at field capacity (FC) and 50 % FC) was applied in two-leaf stage and four levels of zeolites(0, 10, 20, 30 ton/ha). Before planting, zeolite was added to the soil in deepness of root development. Results of ANOVA showed significant effect of irrigation and zeolite on the stem length, stem and leaf weight, chlorophyll a and b, total chlorophyll, chlorophyll index (SPAD). There were significant effect of irrigation on chlorophyll b, leaf proline content and carotenoid, and however significant interaction effect between irrigation and zeolite on the number of leaf, leaf area, leaf width, leaf length and stem diameter, too. The results indicated that water deficit stress significantly decreased stem length, stem weight, leaf weight, leaf chlorophyll content and carotenoid and proline, Whereas the application of zeolites compensated the negative effect of drought stress, especially in high rates of polymer application (30 ton/ha). The highest stem length (23.03 cm), stem weight (0.64 g/plant), leaf weight (0.65 g/plant), leaf chlorophyll content (24.58 mg/g) and carotenoid (1.65 mg/g) were obtained from application of 30 ton/ha zeolite. These findings strongly suggested that the irrigation intervals of Lathyrus could be increased by application of zeolite.