The population density of elateridae larvae on the fields after wheat growing in the region of sombor yugoslavia 1979 1983
Radin, Z.; Durkic, J.; Keresi, T.
Zastita Bilja 36(1): 57-63
Larvae Elateridae belong to the group of the most important pests on row crops in the northeastern part of Yugoslavia. In the region of northwest Backa with its center in Sombor, which covers 192,000 ha arable land, investigations of Elateridae were made each year on about 6,000-7,000 ha on chernozem and meadow black earth. Soil inspection was used. In the course of 5 yr material from 513 fields were collected after wheat growing, 18,476 soil samples of 0.25 m2 each were taken. The number of wireworms on the fields after wheat growing in the region of Sombor during the period from 1979-1983 moved from 4.6/m2 up to 9.1/m2, with an average number of 7.0/m2. On 42.5% of inspected fields there was 1-5 wireworms/m2; on 28.7% fields 5-10 wireworms/m2 were found. Agriotes ustulatus Schall.dominated in the whole population with 73.47%, but Adrastus sp. was also represented with 23.19%. On the fields where sugar beet had been grown and after the chemical control of the pests in spring, an average of 1.4 wireworms/m2 was found during 5 yr investigation. The population of Elateridae larvae appears again regardless of the time passed when wheat is grown on the same field 2, 3 or 4 yr after the treatment. It was necessary to treat 99.8% of fields for sugar beet growing. New complex methods of pest control (agrotechnical-biological) must be introduced because the number of wireworms is permanently rising even with the constant chemical treatment.