History and concept of Sterile Insect Technique

The History of Sterile Insect Technique

SIT technology was initiated by E.F. Knipling in the 1930s, when he worked with the screwworm fly, a devastating scourge of cattle in North America. The first successful use of SIT to control screwworm was on the island of Curaçao in 1953.

Since then SIT has been further refined and developed for a number of insect pests mainly by the United States Department of Agriculture and the FAO/IAEA.

SIT has been developed to suppress or eradicate more than 20 insect pests, many of them being fruit flies and other fruit pests. There are at least 15 facilities around the world rearing Mediterranean fruit flies, and another 10 or so rearing other species of fruit flies. Production of sterile pupae varies from approximately 5 million per week to as many as 5 billion per week, the latter at the El Pino Facility in Guatemala.

The El Pino Medfly Rearing Facility in Guatemala

The Concept of Sterile Insect Technique

Simply put, SIT is birth control for insects. It is used primarily to control or eradicate insect pests, usually crop pests or human and animal pests. The target insect is reared in great numbers, and the males sterilized, usually using gamma radiation. The sterile males are released weekly in high numbers in the target areas, usually throughout the year. They mate with the wild females which results in infertile eggs being laid, and provided certain other population management activities are properly carried out, the wild population then declines rapidly.
It is a proven technique, used in various other countries to create pest-free areas or areas of low pest prevalence. It is an ecologically compatible technique that should only be used as an area-wide technique – over large areas, and cannot be implemented on a farm-by-farm basis.

SIT is management intensive, requiring good coordination, communication, and the active cooperation of all the growers in an SIT area.