Sterile insect technique

Knipling, E. F. (1982) "Present status and future trends of the SIT approach to the control of arthropod pests." In Sterile Insect Technique and Radiation in Insect Control, pp. 3-23. IAEA/FAO, Vienna. 

Construction of sex-linked genetic markers in major economic pests will facilitate expansion of genetic control methods such as the sterile insect technique and backcross sterility in Heliothis virescens. 

International Atomic Energy Agency. 1974a. The Sterile-Insect Technique and its Field Applications. Proceedings of a panel, Vienna, November 13-17, 1972. IAEA, Vienna. Publ. No. STI/PUB/ 364. 137 pp. 

Genetic Control. Some Insect pests have been successfully controlled by releasing sterile Insect males in sufficient quantity so that the pest population cannot reproduce. This has proven particularly effective in the control of the screwworm fly, a major pest of cattle (33). Genetic engineers may be able to provide other genetic techniques that will enhance the control of crop pests (34). 

Some forms of pest resistance involve. hanging the pest rather than the host plant. The best example of autocidal resistance is the sterile male technique used to control. nsects. Scientists rear thousands of males of a particular insect species under controlled conditions, then sterilize them with x-rays. These sterilized males are released in the wild to mate with females of the same species. Since the males are sterile, mated females do not produce eggs, causing populations to drop drastically over time. (The technique is restricted to insect species with females that only mate once.) This method is most successful when the sterile males compete aggressively with the natural population of fertile males. A working example of autocidal resistance occurs at the border of Mexico and California, where sterile males of the Mexican fruit fly are released to help control populations and to prevent the pests from entering California. 

Standing advantages of the technique is that, unlike chemical methods, it becomes more efficient as the population of the pest is reduced because of the increasing ratio of radiation-sterilized insects to fertile ones. There are, however, the following requirements for a successful application of the technique ... 

LaBrecque, G. C., and J. C. Keller (eds.). 1965 Advances in Insect Population Control by the Sterile-Male Technique. International Atomic Energy Agency, Vienna, Tech. Rep. Ser. No. 44. Publ. No. STI/DOC/10/44. 79pp. 

Genetic Control. Manipulation of the mechanisms of inheritance of the insect pest populations has occurred most successfully through the mass release of sterilized males, but a variety of other techniques have been studied, including the environmental use of chemosterilants and the mass introduction of deleterious mutations, eg, conditional lethals and chromosomal translocations (58 ndash 60) (see GENETIC ENGINEERING). 

Sterile Males— Males of some pest insect species may be reared and sterilized in laboratories and released in large numbers into infested areas to mate with native females. These matings produce infertile eggs or sterile offspring and help reduce the pest population. This technique has been used successfully in only a few species and is still being developed. The screw worm, which attacks cattle, is one insect on which this technique has been effective. 

Radiation doses of ss 80 J/kg have been used to sterilize the males of insect species, which are released after sterilization and mate with females. In this way, further reproduction of the species is reduced or prevented. The technique has been applied in the USA, Mexico, Egypt, Libya and other countries to eradicate screw-worm flies and other insect species that are threats to agriculture. 

Choose healthy plants. Inspect new plants refore introducing them to your yard or garden. Look for signs of disease and insects, and reject any that look suspicious. If available, buy certified disease-free plants and seeds. Inquire about seed sterilization practices at your seed source. Buy from suppliers that use sanitation procedures and heat-sterilizing techniques instead of synthetic chemicals to control disease on nursery stock and seeds. 

Radiation has been used to sterilize (80 Sv) the males of certain insect species which when released (the ratio between the sterilized and untreated males was approximately 4 1), mate with females and prevent further reproduction of the species. This technique has been used in the US, Mexico, Egypt, Libya, etc to eradicate screw worm flies which can cause huge damage to the cattle industry. The technique is now also used against other insect species which are threats to agriculture. 

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