Quality control in mass-reared melon files, Bactricera cucurbitae, after eradication is discussed, based on the results of artificial selection experiments. First, a brief history of quality control in mass-rearing of insects is described. In practical mass-rearing of melon fly, many traits habe already been differentiated between mass-reared and wild files. These differing traits are reviewed and the factors which caused these differences are considered. It was considered that the differences between wild and mass-reared melon files depended on the selection pressures from the mass-rearing method. Next, the results of several artificial selection experiments using the melon fly are reviewed. Finally, consideration is given to some correlated responses to artificial selection in mass-rearing. Longevity that is correlated to early fecundity was successfully controlled by artificial selection for reproduction in the mass-rearing system. On the basis of these results, an improved method for quality control in mass-reared melon fly with considerations for quantitative genetics is discussed.ウリミバエ根絶後の大量増殖における虫質管理について，人為選択実験の結果に基づいて考察した．まずミバエ類の大量増殖における虫質管理の簡単な歴史について触れた．沖縄県で現在飼育されている大量増殖虫は，野生虫と比べて多くの形質が異なっている．そこで現在飼育されている大量増殖虫の特質を明らかにし，なぜそのような違いが生じたのかについて考えた．その結果，形質の変化には大量増殖方法による選択圧が大きく関与していると考えられた．そこで，大量増殖虫のいくつかの形質に対する人為選択実験の結果をレビューした．さらに，大量増殖虫の繁殖と寿命に関わる形質を人為的に操作することに成功した沖縄県の事例を紹介した．以上の結果をふまえて，ウリミバエ根絶後の大量増殖における虫質管理の方向性について考察した
