Understanding the variability and the association existing among natural rubber genetic materials for important traits is vital for the effective utilization of such materials for breeding purposes. The aim of this study was to determine the genetic variability and associations among the nine traits used as indices for picking drought tolerant genotypes. The test genotypes were RRIM 600, NIG 800, NIG 801, NIG 802, NIG 803, NIG 804, PR 107, RRIM 628, GT I, and PB 5/51. Observations were made on

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... lant height, number of leaves, plant girth, plant vigor, percentage plant survival, leaf yellowing, leaf senescence and leaf fall among the ten genotypes. Results obtained from the analysis of variance (ANOVA) showed that there were significant variations for all the characters studied. The plant height, number of leaves, plant girth, leaf area, leaf yellowing, leaf senescence and leaf fall, showed highly significant variations across the genotypes and drought stress periods. Genotypic variances were relatively high for number of leaves, leaf fall, plant survival and plant girth leading to high broad sense heritability estimates 0.96, 0.82, 0.76 and 0.71 respectively. Also high genotypic coefficients of variation (GCV) for all the traits from 29% to 395% and high genetic advance at 20.98% in leaf area to 25.55% in plant girth, leaf yellowing (34.13%), plant vigor (36.16%) and 69.98% in number of leaves were obtained. All the traits except percentage plant survival had positive and significant association with each other. The negative correlation between plant survival and other agronomic characters suggests that a considerable decrease in percentage plant survival will increase agronomic traits such as plant height, girth and vigor. Striking a balance between plant survival, also a desired trait and other agronomic characters is necessary.