Baculovirus resistance in codling moth (Cydia pomonella L.) caused by early block of virus replication.

An up to 10,000-fold resistance against the biocontrol agent Cydia pomonella granulovirus (CpGV) was observed in field populations of codling moth, C. pomonella, in Europe. Following different experimental approaches, a modified peritrophic membrane, a modified midgut receptor, or a change of the innate immune response could be excluded as possible resistance mechanisms.

Sex linkage of CpGV resistance in a heterogeneous field strain of the codling moth Cydia pomonella (L.).

The occurrence of codling moth populations in European apple orchards that were not controlled by Cydia pomonella granulovirus (CpGV) is the first reported case of field resistance against a baculovirus control agent. A monogenic dominant sex-linked mode of inheritance was previously demonstrated in single-pair crosses between a homogeneous resistant (CpRR1) and a susceptible (CpS) laboratory strain of codling moth. However, resistant field populations (CpR) are more heterogeneous in their levels of resistance, and the possibility that they could harbor different resistance genes to CpRR1 had not been directly addressed.

Overcoming the resistance of codling moth against conventional Cydia pomonella granulovirus (CpGV-M) by a new isolate CpGV-I12.

Recently, codling moth (CM, Cydia pomonella L.) populations with a significantly reduced susceptibility to C. pomonella granulovirus (CpGV) products have been observed in Germany.

Rapid emergence of baculovirus resistance in codling moth due to dominant, sex-linked inheritance.

Insect-specific baculoviruses are increasingly used as biological control agents of lepidopteran pests in agriculture and forestry, and they have been previously regarded as robust to resistance development by the insects. However, in more than a dozen cases of field resistance of the codling moth Cydia pomonella to commercially applied C. pomonella granulovirus (CpGV) in German orchards, resistance ratios exceed 1000.