Endogenous Hormones's Adjust Mechanism of Cichorium intybus L. under Drought Stress

[Objective] The aim was to study endogenous hormones's adjust mechanism of Cichorium intybus L.under the drought stress.[Method] The contents of three kinds of endogenous hormones(ABA,IAA and GA3) in three chicory(C.intybus L.) strains(space-mutagenesis-bred strains PA-82 and PA-43 and their initial strain CK) under different drought stress were determined by using high performance liquid chromatographic method.[Result] Under drought stress,the ABA contents of three strains increased,among them the ABA contents of PA-82 with strong drought resistance and CK with middling drought resistance didn't change under the light drought stress,but they ascended largely under the modest and severe drought stress,while the ABA content of PA-43 with weak drought resistance had an equipotent increase under each water stress disposal.Under drought stress,the IAA contents of three strains increased,among them the increase of IAA content of PA-82 was more than that of CK and PA-43.Under drought stress,the GA3 contents of three stains decreased,among them the decrease of GA3 content of PA-82 and CK were more than that of PA-43.Principal component analysis result showed that ABA was chosen for evaluating drought resistance of chicory.[Conclusion] The research lay the foundation for the application of artificial hormone regulation in drought-resistance cultivation and breeding of C.intybus L..