Endogenous Hormone Content of Fleshy Root in Relation to Early Bolting in Summer Cultivated Carrot on Plateau Study on exogenous hormones inducing parthenocarpy fruit growth and development and quality of Siraitia grosvenorii Effects of Nitrogen on the Antioxidant Enzyme Activities and Endogenous Hormone Contents of Cotton Leaf under Drought Stress and after Soil Re-Watering during the Flowering and Boll-Forming Stage