English

Abstract

Rice is one of the important cereal crops drastically affected by water scarcity in rice ecosystems. In a pot study, the impact of externally applied gibberellic acid (GA3), indole acetic acid (IAA) and kinetin was investigated on assimilates mobilization and yield parameters of rice under water stress. Twenty five days seedlings of two rice genotypes KS-133 and Basmati-2000 were transplanted in soil filled pots and sprayed with GA3, IAA and kinetin each of 10 M concentration at panicle initiation stage. Water stress was imposed to plants 80 days after transplanting for 10 days. Water stress (p≤ 0.05) reduced leaf chlorophyll content and yield of rice but increased the concentration of proline, leaf soluble protein and enhanced mobility of assimilates from leaves to grains. Application of GA3 and kinetin significantly (p≤ 0.05) increased chlorophyll content, growth and yield attributes in both genotypes under water stress conditions. However, IAA application did not improve the grain yield in rice genotypes under water stress. The positive impact of GA3 and kinetin spray was imitated in the form of enhanced solute accumulation; enhanced growth and greater grain assimilate deposition. This may be concluded that GA3 and kinetin can be applied exogenously prior to flower initiation in rice to reduce panicle sterility by increasing assimilates mobility under water deficit for optimal economic yield. © 2016 Friends Science Publishers