ИСТИНА

The codling moth granulovirus (Cydia pomonella granulovirus, CpGV) is an efficient biological agent of the codling moth which is of great importance in organic fruit growing. Currently there are CpGV preparations from different manufactures available in Europe and about 100-150.000 ha per year are used. Although CpGV has a very narrow host range, in addition to C. pomonella also C. molesta can be infected with lower efficiency. So far there is no effective control agent in organic farming for C. molesta, therefore, the direct control approach using CpGV is tested. Four different CpGV isolates were tested in bioassay against a laboratory strain of C. molesta and the LC50s (median lethal concentration) of these isolates were determined. The rating was carried out after 7 and 14 days. In addition to the biological activity of isolates against C. molesta the CpGV isolates were characterized by restriction analysis. The restriction profiles were compared to the known profiles of CpGV-M. A virus isolate (CpGV-V22, Andermatt Biocontrol), which has great potential as bioinsecticide, is a mixture of different genotypes. Therefore an in vivo cloning procedure was performed. Thereby, a pure genotype "V22P" could be isolated from this mixture of different genotypic variants. In view of using the cloned in vivo CpGV-V22P in pest control it is interesting to determine to what extent the individual genotype shows a higher infectivity for C. molesta than the corresponding CpGV-V22 isolate. The differences in biological activity between mixture and pure genotype are determined in a bioassay.