Study on Responses Characteristics of Leaf Water Potential in Amorpha fruticosa Seedlings to Biochar-based Fertilizer and Drought Stress
To investigate the response characteristics of leaf water potential in Amorpha fruticosa seedlings un-der drought stress and rewatering,various amounts of biochar-based fertilizer were applied.Pot experiments were conducted in a greenhouse to evaluate the effects of different application rates of biochar-based fertilizer(750 kg/hm2,1 500 kg/hm2 and 2 250 kg/hm2),different levels of water stress(100.00%,87.84%,70.00%,52.16%,and 40.00%soil relative water content),and rewatering conditions on leaf water poten-tial in A.fruticosa seedlings.The results revealed that severe drought conditions led to a decrease in leaf water potential and an increase in the water stress index of A.fruticosa seedlings when biochar-based fertilizer was applied at rates of 750 kg/hm2,1 500 kg/hm2 and 2 250 kg/hm2.Among the treatments,the lowest leaf wa-ter potential in seedlings was observed under the 40.00%SRWC treatment.Notably,the application of 2 250 kg/hm2 of biochar-based fertilizer resulted in a decrease of 0.67 MPa in leaf water potential after 15 days of drought stress.However,the leaf water potential of A.fruticosa seedlings exhibited recovery over time upon rewatering.A strong correlation was found between the severity of drought stress and the duration of the drought.Conversely,after 6 days of rewatering,the leaf water potential of A.fruticosa seedlings subjected to 30 days of drought stress did not fully recover to the control level in the 52.16%and 40.00%SRWC treat-ments.However,in the case of 15 days of drought stress,the leaf water potential of A.fruticosa seedlings re-covered to the control level and even exhibited compensation and super-compensation effects.
Drought stressBiochar-based fertilizerLeaf water potentialRewaterRecovery