Influence of water stress on phenological development, biomass production and yield of Malaysian aerobic and lowland rice

Abstract

This experiment was conducted to examine the comparative growth performance and yield of the first Malaysian aerobic rice variety, MARDI Aerob 1 (MA1) along with local lowland rice, MR 253 grown under water stress condition at selected growth stages. The experiment consisted of four treatments with three replications arranged in a randomized complete block design. The four treatments consisted of the control with no water stress throughout (T1), and water stress imposition at panicle initiation (T2), flowering (T3) and ripening (T4) stages. Water stress treatments were terminated when water deficit symptoms such as leaf rolling and wilting were detected. The effects of stress were assessed using parameters related to phenology, biomass and yield components. Results showed that both varieties were significantly affected, when water stress was imposed at the panicle initiation stage. At this stage, the water stress delayed the phenological development, reduced the panicle dry mass, and severely caused grain yield reduction for both varieties. The MR 253 variety had higher grain yield than MA1 under normal aerobic condition but not under water stress, while MA1 still was able to maintain reasonable high yield even under water stress condition, except when the water stress occurred at the panicle initiation stage. Panicle initiation stage was the most sensitive period for both varieties as water stress at this stage greatly affected the overall growth performance and grain yield for both varieties.