Survival rate of Plodia interpunctella (Lepidoptera: Pyralidae): On different states of wheat and rye kernels previously infested by beetle pests

The present study was undertaken to determine survival rate of Plodia interpunctella (Hübner, 1813), reared on different mechanical states of Vizija winter wheat cultivar and Raša winter rye cultivar, previously infested with different beetle pests. Wheat was previously infested with Rhyzopertha dominica, Sitophilus granarius, Oryzaephilus surinamensis and Cryptolestes ferrugineus, while rye was infested only with O. surinamensis. Kernels were tested in three different mechanical states: (A) whole undamaged kernels; (B) kernels already damaged by pests and (C) original storage kernels (mixture of B and C type). No P. interpunctella adult emerged on wheat kernels, while 36 adults developed on rye kernels. The highest abundance reached beetle species who fed with a mixture of kernels damaged by pests and whole undamaged kernels. Development and survival rate of five different storage insect pests depends on type of kernels and there exist significant survivorship correlations among them.