Quantitative Analysis of ABA and SA in Rice (Oryza sativa L.) Grown Under Drought Stress

Abstract

Rice cultivation requires plenty of water for its proper growth, development, and productivity. The regular life cycle of rice plants is disrupted by moderate to severe drought. Both abscisic acid (ABA) and salicylic acid (SA) have involvement in rice physiology under drought. With the limited information, we aimed to study the relationship between ABA and SA concentration in leaves of rice plants under drought. The experiment was performed on a drought-sensitive variety of Swarna MTU 7029 rice. The HPLC method was used to analyse the endogenous ABA and SA content. This study provided data on ABA and SA content in 0.5 mM SA treated and untreated 56 days old rice plants at 7, 14 and 28 days of drought. The result showed that the concentration of ABA was enhanced by 74.6%, 82.8%, and 99.4% during 7, 14, and 28 days of drought, respectively, while it was increased by 64.6%, 74.3% and 78.5% in SA treated plants under 7, 14 and 28 days drought, respectively. The concentration of SA enhanced by 132.2%, 19.7%, and 3.0% during 7, 14, and 28 days of drought, while it was increased to 137.5%, 54.8%, and 23.2% in SA treated plants under 7, 14, and 28 days drought, respectively. This explains that on the 7th day of drought stress, SA may suppress the formation of ABA but not much on the 14th and 28th days of drought stress in treated rice plants. This outcome helps study the interaction of ABA and SA at the gene level under drought stress.