Morphological, physiological and molecular responses of Indonesian cassava to drought stress

Abstract

In Indonesia, investigations of drought-tolerant cassava by characterizing the morphological, physiological, and molecular responses have not been carried out. This research was aimed to characterize the morphological, physiological, and molecular features of 10 Indonesian cassava varieties (Adira 1, Malang 1, Cimanggu, Kaspro, Ketan, Litbang UK-2, Malang 4, Malang 6, UJ-3, and UJ-5) under drought stress. 30 days after planting, drought stress was applied by stopping irrigation of plants for 15 days. The plant height, root system, and wilting were measured as morphological responses of cassava. For physiological responses, the percentage of opening stomata, chlorophyll, and hydrogen peroxide (H2O2) content were also investigated. Gene expression of MeGBF3 and MeMSD was evaluated to analyze the response of candidate drought-tolerant genotypes. The studied parameters revealed that drought stress inhibits the growth of cassava. Some genotypes could not survive because the excessive content of H2O2 would be toxic to plant cells and disturb the plant growth. The up-regulated gene expressions of MeGBF3 and MeMSD has correlations with morphological and physiological responses of cassava to drought stress. Adira 1 and Kaspro are thought as drought-tolerant genotypes due to the morphological, physiological, and molecular responses.