Studies On The Physiological And Biochemical Mechanism On Ethephon Promoting Effective Tillering In Sugarcane

Field and barrel-cultured experiments were conducted, and physiological and biochemical analyses in laboratory and physiological-ecological analyses in fields were employed to investigate the effects of different concentrations of ethephon on the activities and isozymes of IAAO, POD~+ in roots, and on root morphology and light response curve of leaves of sugarcane plants at tillering stage. And especially for the treatments of 200 mg/L and 0 mg/L (control) ethephon applied by foliar spray and seedcane soaking, the effects on the endogenous hormone, and the activities and isozymes of IAAO, POD~+, POD~- in the roots, mother stem base and tiller stem, respectively, at the tillering stage, and on the root morphology, and on the photosynthetic characteristics including chlorophyll content, gas exchange parameters and fluorescence parameters, and the nutrient absorption of the plants including the contents of nitrogen, phosphorus and potassium in the roots, stems and leaves were comparatively studied. For the field experiments, two sugarcane varieties, ROC16 and ROC22, were employed to investigate the effects of different concentrations of ethephon on the population structure, photosynthetic characteristics, agronomic characters, and cane yield and quality in both the plant and ratoon crops. The purpose of the present study is to illustrate the physiological and biochemical mechanism on ethephon promoting effective tillering in sugarcane. The experimental results were as follows.1) As compared with the control, the treatments with different concentrations of ethephon showed higher activity of peroxidase but lower IAA oxidase in the...