Mango weevil: cobalt-60 gamma -irradiation of packaged mangoes.
Laboratory studies were carried out in Hawaii on the elimination of Sternochetus (Cryptorhynchus) mangiferae (F.) from packaged mangoes by exposure of opposite sides of each carton to gamma -radiation from radioactive cobalt (60Co). Minimum doses of 20.6 and 32.9 krad eliminated infestations of about 1200 eggs, larvae, pupae and adults in fruits in corrugated fibre-board cartons with absorber thicknesses (the product of the density of the carton (g/cm3) and the mid-distance from the irradiated sides of the carton) of 2.56 and 4.27 g/cm2, respectively. Also, the few irradiated adults recovered alive six months after treatment at 20.6 krad of cartons with absorber thicknesses of 3.2 and 3.97 g/cm2 were sterile and had short lives. As the dose was increased, the length of life of the treated adults decreased logarithmically, the mean length of life being about 3.5 and 2.2 months following treatment at 20.6 and 32.9 krad, respectively.<new para>ADDITIONAL ABSTRACT:<new para>Minimum doses of 20.6 or 32.9 krad eliminated ca. 1200 eggs, larvae, pupae and adults of Cryptorhynchus mangiferae from mango fruits in corrugated fibreboard cartons with absorber thicknesses of 2.56 and 4.27 g/cm2, respectively. The fruit was not damaged.