Exogenous melatonin alleviated growth inhibition and oxidative stress induced by drought stress in apple rootstock

Drought stress is one of the major environmental obstacles that limit production and development apples (Malus domestica Borkh.). The role melatonin well known in protection plants under stresses. In this study, we investigated effect on apple rootstock M. hupehensis Rehd drought stress. results showed inhibited growth dramatically reduced root surface area, volume, number tips forks, diameter. Drought-induced inhibition was significantly decreased by adding melatonin. Net photosynthetic rate (Pn), intercellular CO2 concentration (Ci), stomatal conductance (Gs), transpiration (Tr), were markedly However, application could mitigate damage to apparatus increase quantum yield PSII photochemistry. Additionally, generation hydrogen peroxide (H2O2) superoxide radicals (O2•–) sharply increased leaves after 4 days stress, accumulation electrolyte leakage (EL) represented oxidative while applying O2•– H2O2 protected membrane from damages. These suggest adverse effects can be minimized apples.