Gas exchange recovery of Calotropis procera Ait. seedling in different irrigation periods

The present study aimed to investigate rate of photosynthetic recovery Calotropis procera seedling under drought stress at greenhouse conditions were conducted. This research was at two separate experiments، first experiments، 6 level periodic drought stress (3، 6، 9، 12، 15 and 18 days of irrigation interval) to 180 days and then second experiment، full recovery seedlings after the first experiment for 36 days in a completely randomized design with three replications. Gas exchange values of seedling under drought stress and recovery were significantly influenced. Drought stress and recovery experiments with increasing values of gas exchange parameters except for the water use efficiency and leaf temperature decreased. Paired T Test، values of water potential seedlings، mesophyll conductance، and intracellular concentration of Co2 and water use efficiency show of the recovery in drought levels. In general photosynthesis، stomatal conductance، transpiration and leaf temperature at the drought levels more than 3 days irrigation approximately in some of drought levels، demonstrated seedling recovery.