Chemical control of pollen beetle in winter oilseed rape

Povećanje rezistentnih populacija repičina sjajnika na piretroide, u svim europskim zemljama i Hrvatskoj, uzrokuje znatne probleme i smanjuje prinos uljane repice. Cilj rada bio je istražiti učinkovitost različitih insekticida u suzbijanju rezistentnih populacija repičina sjajnika: pimetrozina, lambda cihalotrina, alfacipermetrina, pirimifos metila, tau fluvalinata, tiakloprida te kombiniranih pripravaka na osnovi aktivnih tvari tiakloprid + deltametrin i klorpirifos + cipermetrin. Poljski pokus postavljen je prema EPPO metodici sa devet varijanata u četiri ponavljanja. Osnovna parcelica bila je 30 m2 . Visina populacije repičina sjajnika praćena je otresanjem terminalnih cvatova (BBCH 38/39 do BBCH 55). Tretiranje je provođeno nakon prijeđenih pragova odluke. Učinkovitost je izračunata formulom prema Henderson-Tiltonu. Rezultati su statistički obrađeni. Pripravci iz skupine piretorida pokazali su slabiju učinkovitost na repičina sjajnika, što je posljedica već utvrđene rezistentnosti, pripravak na bazi aktivne tvari tiakloprid ima slabiju učinkovitost zbog nižih temperatura u vrijeme suzbijanja repičina sjajnika, a pripravak na bazi aktivne tvari pimetrozin pokazao je vrlo visoku učinkovitost u suzbijanju repičina sjajnika.The increase of resistant populations of pollen beetles to pyrethroids, in all European countries and Croatia, leading to significant problems and yield loss of oilseed rape. The aim of this study was to investigate the effectiveness of various inescticides on resistant populations of pollen beetles: pymetrozine, lambda cyhalothrin, alfacipermetrin, pirimiphos methyl, tau fluvalinate, thiacloprid and combination active ingredient thiacloprid + deltamethrin and chlorpyrifos + cypermethrin. Field trial was conducted according to EPPO methodology with nine variants in four replications. The basic plot size was 30 m2. Population of pollen beetles were sampled using the beating method (BBCH 38/39 to BBCH 55). The efficiency was calculated by the Henderson -Tilton formula. The results were statistically analyzed. Pyrethroids showed lower efficiency at pollen beetle because of established resistance, active ingredient thiacloprid has lower efficiency because of the lower temperatures that are present in field, while the active ingredient pymetrozine demonstrated a very high effectiveness in chemical control of pollen beetle