Oviposition attractants and stimulants from host plant fruits and leaves for the melon fly, Bactrocera cucurbitae Coquillett

摘要

Fruits and leaves of the bitter melon, Momordica charanlia were evaluated of their roles in attracting and stimulating oviposition of the melon fly, Bactrocera cucurbitae. Volatile oils extracted by steam distillation and diluted with CH2CL2 to obtain 0.8,0.16,0.08 mg fruit and leaf equivalents were tested for female attraction in cubical screened cages of 3 cu.m and I cu.m at long and medium range, respectively. It was found that volatile oils of 0.8 mg fruit and leaf equivalents attracted significantly more females, averaged 17.2 and 9.7 females at long range and 22.1 and 17.7 females at medium range, respectively, than other concentrations and control (CH2CL2). Fruit and leaf juices prepared by pulverizing and straining were tested for stimulating oviposition. When females were allowed to perceive only the juice odor, they laid significantly more eggs, averaged 5.1 and 2.6 eggs, respectively in fruit and leaf juices than control (water). However, when females were allowed to contact and perceive juke taste, they laid significantly more eggs, averaged 9.4 eggs, in fruit juke than leaf juice and control. In addition, fruit jukes prepared from rind, flesh and inner pulp were assayed for stimulating oviposition. The results showed that juices of flesh and inner pulp stimulated significantly more oviposition, averaged 22.4 and 18.2 eggs, respectively, than that of rind and control. Rind juice stimulated significantly more oviposition, averaged 11.2 eggs, than control.