著者

佐藤 洋 白井 保久 田中 定典 今村 太郎 宮ノ下 明大

出版者

日本応用動物昆虫学会

雑誌

日本応用動物昆虫学会誌 (ISSN:00214914)

巻号頁・発行日

vol.47, no.3, pp.97-100, 2003 (Released:2003-11-25)

参考文献数

14

被引用文献数

3 2

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The purpose of this study was to determine the mechanisms by which Plodia interpunctella (Hübner) infest chocolate cartons and to test the effect of sealing tightness of wrapping film on infestation. The carton samples were wrapped with 25 μm thick OPP film by an industrial wrapping machine. Each chocolate carton was placed in a closed plastic box (215×147×130 mm) together with 5 mg of eggs, two weeks old larvae, three weeks old larvae or five pairs of mating adults of P. interpunctella. The plastic boxes were kept at 25°C and 70% R.H. The number of larvae infesting chocolate was recorded after 10 days. Only newly hatched larvae were able to invade the chocolate cartons in these experiments. However, no entry holes made by the larvae were found on the outer coveringfilm, indicating the larvae invaded through tiny unsealed portions of the outer coveringfilm. To test the effect of tightness of the film on larval invasion, outer coveringfilm of chocolate cartons with different air leak values (>100, 100–200, 200–300, 300–500 cc/min) were exposed to newly hatched larvae. A carton without wrapping was used as a control. In cartons with less than 100 cc/min air leak, no larvae were found three weeks after the beginning of the experiment. Furthermore, the number of larvae which invaded cartons increased as the air leakage value increased. It is recommended that the air leakage value of the outer coveringfilm should be less than 100 cc/min to protect chocolate cartons from the infestation of P. interpunctella.