. Bulletin. Natural history; Natural history. September 1985 125 Years of Biological Research 193. Fig, beetles killed after 5 days of feeding on cut fruit of C. pepo x C. hybrid dusted with g of methomyl insecticide (Rhodes et al. 1980). ( ha). (Metcalf et al. 1982,1983a). In experiments in sweet and dent corn such applications killed from 160,000 to 230,000 Diabroticina beetles per acre ( ha) and remained effective for at least 2 weeks. A notable feature of the Cuc-kairomone insecticide baits is that the quantity of insecticide re- quired per unit of area is o
. Bulletin. Natural history; Natural history. September 1985 125 Years of Biological Research 193. Fig, beetles killed after 5 days of feeding on cut fruit of C. pepo x C. hybrid dusted with g of methomyl insecticide (Rhodes et al. 1980). ( ha). (Metcalf et al. 1982,1983a). In experiments in sweet and dent corn such applications killed from 160,000 to 230,000 Diabroticina beetles per acre ( ha) and remained effective for at least 2 weeks. A notable feature of the Cuc-kairomone insecticide baits is that the quantity of insecticide re- quired per unit of area is only about 1 percent of that required for conven- tional spray applications for Diabro- ticina beetle control. The applications are highly selective because of the kairomonal effect on the Diabroticina, and other insects, including beneficial insects, are not appreciably affected. HOST-PLANT RESISTANCE BY ANTIXENOSIS (NONPREFERENCE) Antixenosis is a major type of host- plant resistance to insect attack in which the plant lacks the characteris- tics desired by insect pests and is an unsuitable host. Antixenosis, therefore, is the major resistance factor limiting most phytophagous insects to a mono- phagous or oligophagous host range. Increasing appreciation of the role of plant allelochemics acting as kairo- mones, suggests that genetic manipu- lations to remove them from cultivars is a logical approach to host-plant resistance. Indeed, this removal has oc- curred inadvertently in the Cucur- bitaceae from primitive man's efforts to find palatable squash, melons, and cucumbers free of the bitter cucur- bitacins. However, antixenosis has had only limited exploitation in the de- velopment of pest-resistant cultivars compared with the development of an- tibiosis, involving genetic manipula- tion to produce or increase allelochem- ics or other factors adverse to host selection and pest development and reproduction (Kogan 1983). The importance of antixenosis as a mechanism for host-pla
Size: 1884px × 1327px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., booka, bookcentury1900, bookdecade1910, booksubjectnaturalhistory
