Effect of drought on endogenous hormone contents and balance in main stem leaves of cotton.

As Lumianyan 28 to be the material,the dynamic changes of endogenous hormone contents in main stem leaves of cot-ton were studied by enzyme-linked immunosorbent assay,two different water treatments drought(the earth RWC60%) and CK(the earth RWC as normal) being set.The results indicated that ZR contents in main stem leaves both showed single peak curves under two treatments,and were very significantly higher but later under drought condition than that of CK.The GA3 content of drought leaves showed second-order peak value,which indicated plants entered the reproductive stage earlier.IAA content in-creased at metaphase in drought stress,but there was no obvious difference in variation tendency between two treatments.It took on a higher peak value of ABA in early drought leaves,and later,ABA ascended slowly to promote premature.Also,drought in-fluenced the dynamic balance of ZR/ABA、GA3/ABA、IAA/ABA and(ZR+GA3)/ABA.It took longer actions of ZR under drought condition;GA3/ABA was closely related in the hormone mutual actions;IAA/ABA played an important physiology role at later growth even in water deficiency.