METABOLOMIC ANALYSES TO EVALUATE THE EFFECT OF DROUGHT STRESS ON CHILI PEPPER (CAPSICUM ANNUUM L.) AT VEGETATIVE STAGE

Abstract

Water shortage due to competition from the various sector, global warming, and climate change leading to less-irrigated field occurred is serious now and future problems for all cultivated plants involving chili pepper. In the situation drought stress give high and significant effect on reducing plant production as a result of alteration in metabolite homeostasis in vegetative tissues. To reveal metabolomic alteration on chili pepper to the stress as main objective of the study, three capsicum genotypes with different tolerance levels to less irrigation condition compared to normal condition were evaluated. Leaves extract of three different chili genotypes grown in less irrigation and normal conditions were analyzed with Gas Chromatography-Mass Spectrophotometry (GC-MS) to reveal profiling of their volatile compounds. Based on principal component analysis (PCA), ten metabolites, i.e., neophytadiene, linolenic acid-ethyl ester, linolenic acid, gamma-sitosterol, phytol, alpha-tocopherol, squalene, i-propyl 7,10,13,16,19-docosapentaenoate, ergost-5-en-3-ol and bicyclo [10.1.0] tridec-1-ene were known to contribute to the existence of diversities in the three genotypes. Furthermore, under hierarchical cluster analyses (HCA) from the ten metabolite compounds, there were only three important metabolites of linolenic acid, gamma-sitosterol, and alpha-tocopherol revealing differences of them compared to the normal irrigation plants. In the less irrigated plants, lowering linolenic acid and increasing gamma-sitosterol and alpha-tocopherol were expressed to response the drought stress. Tolerance chili plants to the stress were affected by their capacity to reduce linolenic acid degradation and to increase alpha-tocopherol and gamma sitosterol accumulation.

Keywords

• capsicum annuum
• drought stress
• gc-ms
• volatile compound
• vegetative stage