|Morales-Ramos, Juan - TX AGRI EXPER STATION|
|Saldana, Guadalupe - TX AGRI EXPER STATION|
|Greenberg, Shoil - TX AGRI EXPER STATION|
Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 25, 1997
Publication Date: N/A
Interpretive Summary: The wasp, Catolaccus grandis, is an effective natural enemy of the boll weevil in cotton fields. To optimize effectiveness of the female wasps, the rearing requires laboratory conditioning prior to field releases. Because the mass production of the boll weevil is expensive and laborious, we tested other insect species for their suitability to induce egg production and oviposition by C. grandis females, and allow development of the parasitoid and determine if any of these insect pests could be used for parasitoid female conditioning prior to field releases. Four species of moths (wax moth, bollworm, tobacco budworm, and rice stalk borer) and 3 species of beetles (cowpea curculio, pepper weevil, and cowpea weevil) were tested. Our results indicated that the moth larvae were not suitable either for wasp development or for stimulating egg production on adult wasp. The 3 beetle species allowed development of the wasps; however, survival to adulthood was considerably reduced in the cowpea curculio and the pepper weevil. When reared in cowpea weevil, the wasps developed from egg to adult in rates similar to those observed when reared in boll weevil. Also, cowpea weevil induced substantial egg production in adult wasps. Nevertheless, the levels of stimulation were lower than those induced by boll weevil larvae. We concluded that cowpea weevils are a promising substitute for the boll weevil in the mass rearing of C. grandis.
Technical Abstract: Seven species of insects were tested as factitious hosts for the boll weevil (Anthonomus grandis grandis Boheman) ectoparasitoid Catolaccus grandis (Burks). Four of these species were lepidopterans: Galleria mellonella (L.), Helicoverpa zea (Boddie), Heliothis virescens (F.), and Chilo plejadellus Zincken. Only H. zea and H. virescens stimulated oviposition by C. grandis; nevertheless this parasitoid did not complete development in any of these lepidopterans. The other 3 species were coleopterans: Chalcodermus aeneus Boheman, Anthonomus eugenii Cano, and Callosobruchus maculatus (F.). Females of C. grandis oviposited and the parasitoids completed development in all 3 coleopteran species tested. However, C. grandis females reared on C. maculatus oviposited a significantly higher number of eggs per day than those reared in A. eugenii or C. aeneus. Even though A. eugenii and C. maculatus were able to stimulate oogenesis on adult C. grandis females after 3-d of exposure, the degree of stimulation was significantly lower than that induced by exposure to weevil larvae.