Effect of cold storage on the quality of Trichogramma nerudai (Hymenoptera: Trichogrammatidae)

The recently discovered species Trichogramma nerudai Pintureau and Gerding (Hymenoptera: Trichogrammatidae) could be useful in biological control programs of forest and agricultural insect pests ( Rhyacionia buoliana Denis and Schiffermuller, Tuta absoluta Meyrick, Plutella xylostella Linnaeus, Cydia pomonella Linnaeus). The possibility of storing T. nerudai at low temperatures and the effects of such storage on the quality of the parasitoid and its progeny were studied. T. nerudai pupae were stored 25, 50, 75, 100, 125, and 150 days at 4 ± 1 °C in a refrigerator, RH=75 ± 5% and in full darkness. T. nerudai pupae were tolerant to cold storage. The numbers of emerged adults, the proportions of deformed adults and the mobility capacity of T. nerudai were greatly affected from 50 days of cold storage onwards. The single quality traits were combined to show the added effect of low emergence, deformation of emerging individuals, and loss of mobility of the non-deformed individuals. The usefulness to cold store T. nerudai pupae up to 50 days is discussed.