Die Richtungen in der gegenwärtigen Entwicklung der biologischen Schädlingsbekämpfungsmethoden in Polen1

The currents of the development of biological control in Poland. Gradually, complex methods of forests protection have been introduced. The great role has been stressed on biological control among others on the protection of birds and colonization of ants. The application in greenhouses of mite Phytoseiulus persimilis becomes more and more important. Among the basical works a great importance is given to the research on viruses of caterpillars. Recently, three new species have been described and their pathogenicity has been investigated. With a particular interest the researches on the parasite nematodes have been developed. These are concentrated on the nematodes of the genus Neoaplectana and the Pristionchus uniformis. The pathogenicity of these nematodes has been investigated in relation to different insects, and also their pathogenicity jointly with the fungi of the genus Beauveria and Paecilomyces. The researches are based on original methods of the cultivation of the nematodes. It has also been taken into consideration the changes of ultra-structure of the host's tissues and hemolimphe.