Susceptibility of codling moth populations originated from Czech Republic to Cydia pomonella granulovirus (CpGV)

Abstract: Baculoviruses are very important agents of organic and integrated crop production due to their favorable ecotoxicological qualities, high selectivity and efficacy. Whereas many European countries and the USA have been using Cydia pomonella granulovirus (CpGV) products to control codling moth for many years, registration of CpGV in the Czech Republic is still in progress. However, in the last six years, populations of the codling moth resistant to CpGV-M isolate were locally found in some European countries. With regard to this experience, the object of this research is to evaluate the susceptibility of various codling moth populations in the Czech Republic to CpGV-M and also to propose a suitable anti-resistance strategy for the Czech Republic. In 2008, the first monitoring of wild codling moth populations’ susceptibility to CpGV-M was evaluated by laboratory bioassays. Three wild populations (Prague-Ruzyne, Bulhary and Velke Bilovice) and a reference (sensitive) laboratory strain were assessed. LC50 in the 7th and 14th day after the infection of the first larval instar was determined by probit analysis. No decreased sensitivity to the CpGV-M was demonstrated.