Effect of water deficiency to the yield of several Sabah Dryland Paddy

Water deficiency is one of the critical factors affecting rice productivity. The average yields from the major crop plants may be reduced by more than 50 percent as a result of water stress. FAO estimated that by 2025, 1.9 billion people will live in countries or regions with absolute water scarcity, and two-third of world population could be under water stress conditions. Therefore, cultivating crops that are tolerant to water deficiency could be a way to ensure food security. Three cultivars of Sabah dryland paddy namely Kambiring, Purak Bukit and Pulut Tadong was used to investigate the effect of water deficiency to their yields. The objectives of the study were to compare the yields between selected Sabah dryland paddy varieties under water deficient condition and to determine the best Sabah dryland paddy variety in term of yield under water deficiency. The days to fifty (50) percent heading, days to leaf curling, relative water content (%), plant height (cm), culm height (cm), number of tillers per plant, number of panicle per plant, percentage of productive tillers (%), panicle length (cm), 1000 grain weight (g) and extrapolated yield (tonnes ha-1) in plants subjected to the water deficit stressed and controlled-well-watered were recorded. The result was analysed using two-way ANOVA and the mean comparison was compared using Tukey's test. Based upon the results, there were no significant difference in the interaction between varieties and the water stress treatment in all parameters. However, there were significance difference in factors, in term of variety, number of tillers/plant, number of panicle/plant, 1000 grain weight (g), extrapolated yields (tonnes ha-1) and in term of water stress level in extrapolated yields (tonnes ha-1). The Purak Bukit rice cultivar was considered to be the highly drought-tolerant cultivar and Pulut Tadong was considered the least tolerant to drought