Ibolya Hatala ZSELLÉR1,
Endre SZÉLL2
1 Plant Health and Soil Conservation
Station of Csongrád Cunty, Hódmezövásárhely,
Hungary
2 Cereal Research Non-Profit
Company, Szeged, Hungary
First occurrence of Diabrotica virgifera virgifera LeConte was detected in Hungary in 1995 in the South-east region close to the Yugoslavian and Romanian border. Since 1996 a trapping system has been operated by the plant protection network all around the country to follow the distribution of the pest. Permanent trapping system has been established to measure the increase of WCR population in different areas, at least three sites in each infected country.
According to the captures of different applied traps Csongrád county is the most infested part in Hungary. In our country the permanent trapping has been continued since 1996 in four sites: Csanádpalota, Hódmezöbásárhely, Nagylak and Szeged. Observations took place at the same fields using pheromone (CSALOMON) and yellow sticky (MULTIGARD and PHEROCON) traps.
Beside trapping of adults determination of larvae development was also carried out by weekly root observations.
On each field 10 emergence cages were set up above one corn plant to measure the number of beetles developed on root system.
The weather in the vegetation season of 2000 can be characterized with extremely high temperature without considerable precipitation for a long period. Under this condition the larvae of WCR hatched 3-4 weeks earlier than in the previous years. Appearance of the beetles were also detected at least 3 weeks earlier in the traps. The number f the adults increased considerably in the pheromone traps in each site compared to previous years. Even higher growth of number of beetles was observed in yellow sticky Multigard traps in the area of Szeged and Csanádpalota. Number of females was much higher in Multigard traps than in the last years.
The number of emerged adults in cages were low in Csanádpalota and Nagylak observation fields. In Szeged the number of beetles varied between 4 and 53 per plant. Significant correlation was observed concerning the number of adults, the root damage and the weight of yield of plants.
In spite the significant increase of WCR population economic damage caused by larvae or adults of the pest was not observed in our country.