Leaf physiological and anatomical characters contribute to drought tolerance of Nusa Tenggara Timur local rice cultivars

Morpho-anatomical characters supporting the resilience of a plant under certain environmental conditions cannot be interpreted individually but thoroughly along with the physiological factors to determine the ability of plants to survive in the drought environment. In this study, we conducted a selection of Nusa Tenggara Timur (NTT) local drought-tolerant rice through the assessment of leaf anatomical characters and their correlation with physiological mechanisms. Materials used in this study were 18 local rice cultivars and 2 control cultivars. The characters of leaf includes epidermal thickness, stomatal density and size, bundle-sheath size, vascular-bundle size and bulliform-cell size were found to be negatively correlated with the changes of chlorophyll, carotenoid, and anthocyanin contents. Moreover the change in anatomical characters is positively correlated with relative water content and cell membrane stability index based on two-way ANOVA test with 95% confidence level. Although most of the cultivars undergo decreasing in all characters measured, several cultivars includes Boawae 100-Malam, Gogo Sikka, Gogo Jak, Hare Tora, Pak Mutin and Gogo Fatuhao showed high potential to be drought tolerant cultivars as found with low reduction percentage of parameters measured.