Extended Impacts of Prolonged Mild Water Stress on Cassava leaves: Physiological Responses and Implications for Irrigation Management

Drought stress at specific growth stages not only impacts cassava growth during those stages but also has lingering effects in subsequent stages. Most existing studies focus primarily on the immediate physiological impacts of drought at particular stages, overlooking prolonged mild drought and overwater stress effects. Our research aims to understand cassava's response to prolonged mild water stress by examining its physiological traits in the leaf. The study in the KU50 cultivar reveals that prolonged mild drought stress impacts leaf area (LA) during the first month but significantly increases LA during the canopy establishment stage (4-5 months after planting, MAP). Conversely, mild overwater stress does not show this effect. Additionally, leaf water potential measurements at pre-dawn and noon demonstrate significant differences between treatments at 1, 3, and 6 MAP. The water potential difference findings suggest that prolonged mild water stress influences each growth stage—leaf and root formation, canopy establishment, and carbohydrate translocation to roots to cassava, at least in this cultivar. This research emphasizes the need to account for the extended impact of mild water stress on cassava growth and development, thereby promoting improved irrigation management practices in cassava cultivation.