(47(2):135-141)Seasonal Occurrence and Chemical Control of Indian-jujube Leafhopper (Quadria pakistanica) (Homoptera: Cicadellidae) in Taiwan

印度棗葉蟬 (Quadria pakistanica (Ashmead)) 為印度棗之主要害蟲，能刺吸葉液並分泌蜜露誘發煤病，影響植株發育至鉅。於本省南部印度棗產地之為害葉率介於2.81－50.50%，平均20.07%。其族群密度自9月開始增加，11月達最高峰，12月開始下降，利用黃色粘片（1521.5cm2）誘集其成蟲數（Y）與葉片若蟲數（X）之直線關係式為Y＝-19.23＋0.59X，r2＝0.9564。於大社地區調查結果本蟲於9～11月受昆蟲寄生真菌 (Vertici llium lecaric) 感染最多，罹病率為1.12－36.47%，平均為4.24%。田間藥劑防治篩選結果，以2.8%賽洛寧乳劑、85%加保利可濕性粉劑、90%納乃得可濕性粉劑及3%亞滅寧乳劑防治效果較佳。Indian-jujube leafhopper damaging leaf and inducing sootymold by excreting sticky honeydew is a destructive insect pest on Indian-jujube in southern Taiwan. The leaves were usually infested by 2.81-50.50% with 20.07% in average. Its population built up rapidly in September, with a peak in November and declined gradually in December. The number of nymphs on the leaf of plant (X) and adults (Y) caught by yellow trap could be expressed as Y = -19.23 + 0.59X, (r2 = 0.9564**). It was highly infected by Verticillium lecaric from September to November ranging between 1.12-36.47% and with 4.24% in average in Ta-sou area. Nine insecticides were tested in this experiment for its control. Results indicated that 2.8% Cyhalothrin EC, 85% Carbaryl WP, 90% Methomyl WP and 3% Fastac EC showed better control