生长素的琼脂包覆控释对烤烟上部叶内源激素代谢及耐熟性的影响OA

Yunyan 87 was taken as the test material.Agar blocks containing IAA were applied to topping wounds after topping,with treatments designated as CK,T1,T2,and T3(CK:agar block without IAA;T1:agar block containing 25 mg/g IAA;T2:agar block containing 50 mg/g IAA;T3:agar block containing 100 mg/g IAA).This study investigated the effects of different treatments on endogenous hormone metabolism and maturity tolerance in upper leaves of flue-cured tobacco.The results showed that T1,T2,and T3 significantly increased IAA content in the upper leaves of flue-cured tobacco and brassinolide(BR)content BR at the later stage of topping,inhibited ABA synthesis,increased the ratios of growth-promoting hormone to ABA,enhanced superoxide dismutase and peroxidase activities(POD and SOD),thereby delaying the decline rates of cell membrane stability index(MSI)and SPAD values.Thus,the application of agar-coated controlled-release IAA to topping wounds delayed leaf senescence,and ultimately improved field maturity tolerance,with the T2 treatment demonstrating the most optimal effects.