Susceptibility of The Saw-Toothed Grain Beetle, Oryzaephlius surinamensis (L.) and The Indian Meal Moth, Plodia interpunctella (Hübner) Infested Stored Products to Cold Plasma حساسیة خنفساء الحبوب المنشاریة وفراشة جریش الذرة الهندیة التى تصیب المواد المخزونة للبلازما

The response of the saw-toothed grain beetle, Oryzaephilus surinamensis (L.) stages and immature stages of the Indian meal moth, Plodia interpunctella (Hubner) to cold plasma generated from corona discharge was investigated. Three voltage levels of cold plasma (150, 200 and 250 V) in a combination of six exposure times between (1-25 minutes) were used. Results showed clearly that, the effect of cold plasma against two insect stages was power and exposure time–independent. In addition, the effect of cold plasma was higher on O. surinamensis stages than immature stages of P. interpunctella and thelarval stage of each insect species was most sensitive to cold plasma, which completely killed at the lowest voltage (150 V)after 20 and 25 min of exposure for O. surinamensis and P. interpunctellalarvae, respectively. While, the pupal stage of each insect was the most tolerant one. Mortality percentages at the highest voltage (250 V) and the longest time of exposure (25 min) were 98.9 and 99.0% for P. interpunctella  and O. surinamensis pupae, respectively. Thus, cold plasma is a promoting technique for stored product insects control in the near future with further studies to know the best method for product exposure without any effect on product quality.