Spatial relationships among Empoasca vitis (Gothe) and Toxoptera aurantii (Boyer) and natural enemies in tea gardens of autumn-winter season in Hefei suburban PRELIMINARY STUDY ON RESISTANCE OF DIFFERENT TEA VARIETIES TO SMALLER GREEN LEAFHOPPER Study on prediction models of beginning period of Empoasca vitis activity peak Genetic variation of Empoasca vitis (Göthe) (Hemiptera: Cicadellidae) among different geographical populations based on mtDNA CO I complete sequence