A study on the dynamics of the oviposition and hatching of Ostrinia nubilalis Hbn. larvae on transgenic maize line MON 810 (DKC 3421YG cultivar) and isogenic maize (DKC 3420 cultivar) was carried out in 2008-2011 in G³uchów (south-eastern Poland). No significant differences were found between the number of egg clusters deposited by O. nubilalis on Bt and non-Bt maize based on the carried out observations. A small, statistically significant difference in the number of egg clusters between the studied cultivars was found only in 2011 and was most likely associated with weather changes. Female O. nubilalis did not significantly prefer any of the cultivars when depositing eggs. In addition, we found no differences in the dynamics of oviposition and larvae hatching between Bt and non-Bt maize. The first egg clusters, their maximum number, and the last egg clusters were found on similar dates for both studied cultivars. Empty egg clusters proving larval hatching were also found on similar dates for Bt and non-Bt maize.
