GROWTH AND DEVELOPMENT OF LARVAE OF THE GRANARY WEEVIL,SITOPHILUS GRANARIUS(COLEOPTERA: CURCULIONIDAE), ON NATURAL AND MERIDIC DIETS

Abstract

AbstractA procedure is described for obtaining free eggs and first-stage larvae ofSitophilus granarius(L.) and rearing the larvae to the adult stage on whole wheat, corn, and rice flours and on diet 2, a casein–starch-based meridic diet.Larval growth rates of males and females reared at 29 °C and 65% R.H. on whole wheat flour were comparable although males attained a higher maximum mean weight. Days to 50% adult emergence (eclosion) were 25.5 and 26.5 for females and males, respectively.Larval growth rates on whole wheat flour were comparable with those on whole corn flour but were better than the rates obtained on whole rice flour; however, growth on diet 2 was improved compared with that on whole wheat flour. The mean weights of 14-day-old larvae were 2.51 ±.40 mg and 1.25 ±.16 mg for those reared on diet 2 and wheat flour, respectively. Similarly, survival to the adult stage was slightly greater (79%) on diet 2 than on wheat (70%). On diet 1, a casein–glucose-based meridic diet, no larvae developed to the pupal stage.