The development of new radiation protocols for insect sterilization using long wavelength x-rays

Abstract

Abstract. Control of insect species for the protection of crops, livestock, and prevention of disease such as dengue fever and malaria is a high priority in today's global economy. Traditional methods such as pesticides have fallen out of favor because its effects are indiscriminate as well as adverse and unpredictable impacts on the environment. Modern novel techniques such as genetic modification have had trouble gaining traction due to ethics concerns and the potential for unforeseen side effects. One approach that has gained traction and has proven its efficacy is the use of ionizing radiation to affect sterility in insect species in order to scale back their population. Known as Sterile Insect Technique (SIT), it has proven very effective in eradicating certain dipteran insect populations. However, when standard sterilization methods developed for dipertans are applied to mosquito populations significant complications arise, such as an inability to compete with non-irradiated males and high mortality rates. We have investigated the effect of treatment with x-rays of different wavelengths on x-ray sterilized mosquito males. Our results have demonstrated that longer wavelength x-rays have a significant effect on the outcome of the sterile males' longevity as well as an increase on the efficacy of sterilization while employing a substantially lower dose. OVERVIEWWe have investigated the utilization of X-ray radiation to achieve sterilization for use in insect pest management programs. The denials of trans-boundary shipments of radioisotopes due to political instabilities are creating a severe constraint to sterile insect technique (SIT) programs around the world as SIT relies on the use of ionizing radiation from radioisotopes for insect sterilization. In SIT programs a large number of sterilized males are released area-wide. The sterile males compete with wild males for female insects. If a female mates with a sterile male then it will have no offspring. Ultimately, this leads to a reduction of the wild population [1]. The sexual sterility is induced with gamma radiation emitted from radioisotopes such as Cesium-137 and Cobalt-60 in almost all SIT programs. The Gammacell 220, a 60 Co irradiator (MDS Nordion International Inc., Ottawa, ON, Canada) has been the most commonly used irradiator and has proven extremely reliable for the purpose of sterilizing target insect pests. This technique has been used successfully for suppression, eradication, containment and prevention of many insect pests [2,3]. The use of sterile insects in area-wide integrated pest management (AW-IPM) programs will continue to expand as constraints are increasing on the use of chemical pesticides in relation to the public's growing demand for a cleaner environment and residue-free food.In 2006, a serious problem arose when the production of the Gammacell 220 irradiator was discontinued. The future availability of these small scale irradiators is in doubt due to growing difficulties associated with the transboundary shipment of radioisotop...

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“…Spermatogenesis initiates at the anterior tip of the testis where germline stem cells (GSCs) undergo successive mitosis and meiosis, and progress through spermatogonia, spermatocyte, and spermatid to produce spermatozoa [13]. Earlier stages of spermatogenesis, especially the mitotic spermatogonia and meiotic spermatocytes, are more sensitive to radiation and are more likely to experience irreversible irradiation-induced chromosomal damage and are eliminated [14]. Irradiation on spermatids and spermatozoa could also lead to dominant lethal mutations.…”

Determine the Gamma Radiation Technique to Sterilization of Insects from Risk Factor

“…Control of insect species for crop and livestock protection, as well as the prevention of diseases such as infectious diseases. Pesticides, for example, have fallen out of favor due to their indiscriminate effects as well as negative and unpredictable effects on the environment [9].…”