安価な原料用サツマイモを用いたアリモドキゾウムシの大量増殖

Abstract

We compared three sweet potato cultivars used mainly for starch and alcohol production, (‘Shirosatsuma’, ‘Shiroyutaka’ and ‘Koganesengan’) with another used for cooking (‘Tosabeni’) to study the feasibility of those three cultivars as an inexpensive diet material for the mass-production of adult sweet potato weevils to be sterilized for insect release. About 1,500 adult weevils (sex ratio≒1:1) were reared on sweet potato storage roots for 2 wk to allow oviposition. Four roots (ca. 800 g) were set out at a time and were replaced with new ones at intervals of 3–4 d. The emergence time of new adults from the roots of Shiroyutaka tended to be a little earlier, and those of Koganesengan a little later than those of Tosabeni. The number of adult weevils available for sterile insect release was no more than 2.7% less when weevils were reared on Koganesengan than when reared on Tosabeni. There was no significant difference in the number of adult weevils produced per gram of sweet potato root between the three cultivars and Tosabeni. Importantly, the percentage of males among emerged adults (sex ratio) was significantly higher in the three cultivars than in Tosabeni. The weevils in a root of Shiroyutaka tended to reach the stage suitable for irradiation 1–2 d earlier than those in Tosabeni. Based on these results, it was concluded that the three cultivars 'Shirosatsuma, Shiroyutaka and Koganesengan' were suitable as diet materials for the mass-production of weevils.