The effectivity of rice husk ash in enhancing drought tolerance on different rice cultivars

Abstract

Silicon is a beneficial element for rice plants that can reduce the effects of drought stress, improve the efficiency of photosynthesis and the availability of essential elements. Rice husk ash (RHA) is alternative to silicon (Si) source. The objective of this study was to analyze the response of different rice cultivar Cempo merah and Segreng to the application of rice husk ash and the relationships to drought tolerance. This research used complete randomized design with three factors: 1) two different cultivars (Cempo merah and Segreng); 2) rice husk ash with three doses 0.4, and 8 t · ha−1; 3) drought treatments of 100 %, 50 %, and 25 % of field capacity. Drought was imposed by with holding water until soil water content reaches 50 % of field capacity (moderate stress) and 25 % of field capacity (severe stress). The results showed that application of RHA at level 8 t · ha−1 increased density of Si bodies in leaves, followed by greater relative water content (RWC) and index of membrane stability. The density of silica bodies was correlated significantly with RWC of Segreng, neither in Cempo merah. Increasing the density of Si bodies in leaves Segreng and Cempo merah showed the effectiveness of the RHA as a source of Si in enhancing drought tolerance.