Effects of climatic conditions on Colorado beetle (Leptinotarsa decemlineata Say) in soil biology and its appearance in Suceava

摘要

During all winters between 2008-2011 was registered only one colder period. If in the last two winters, this was registered in the first decade of January, in the winter 2007-2008 the coldest period was the third decade from January, and in the winter 2008-2009 the lowest temperatures, in the air and on soil, were registered in the third decade from February. In order to evaluate the biological reserve were made 15 surveys on the 0-40 cm depth, at the end of October and in the following year after the defrosting of the whole soil profile. The results of the surveys show that in the analyzed winters only 29% were registered significant losses of the hibernate adults. From a total of 30 emergences in the year 1976-1995 and 2008-2011, 68% from these were produced in April and only 32% in May. During 1976-1991 the tendency of emergence of the hibernate adults was towards the end of April and the first decade of May, following that in the last 10-15 years due to the general global worming, the apparition of the hibernate adults to be produced earlier, respectively the decade second and third of April.