Susceptibility of western flower thrips (Frankliniella occidentalis Pergande 1895) on insecticides

Kalifornijski trips (Frankliniella occidentalis) najvažniji je štetnik plodovitog povrća u zaštićenim prostorima. Izrazita polifagnost, kratki životni ciklus, visoki potencijal razmnožavanja i veliki broja generacija omogućuju brz razvoj rezistentnosti koja je zabilježena u cijelom svijetu pa i na području Hrvatske, gdje je utvrđena na pripravke iz skupine piretroida i neonikotinoida na svim testiranim populacijama, a samo pojedine testirane populacije bile su osjetljive na pripravke na osnovi aktivne tvari spinosad. Cilj rada je utvrditi različitu razinu osjetljivosti odraslih oblika kalifornijskog tripsa na aktivne tvari iz skupine piretroida, neonikotinoida i spinosina. Tijekom 2019., otresanjem biljnih dijelova paprike i krastavaca, prikupljeni su odrasli oblici kalifornijskog tripsa na području četiri županije, s devet lokaliteta, a testiranje se provodilo prema IRAC test metodi broj 10. Tijekom istraživanja testirane populacije kalifornijskog tripsa bile su rezistentne na osam lokacija na aktivnu tvar lambda-cihalotrin. Visoka rezistentnost abamektina utvrđena je na gotovo svim lokacijama, osim s lokaliteta Ferovac gdje je utvrđena umjerena rezistentnost. Populacije kalifornijskog tripsa bile su rezistentne na aktivnu tvar spinosad, jedino je populacija Mlinište 1 (krastavac) bila visoko osjetljiva. Zbog nedovoljne učinkovitosti dopuštenih pripravaka učinkovito suzbijanje kalifornijskog tripsa može se provoditi samo u sklopu integrirane proizvodnje odnosno integrirane zaštite povrća.Western flower thrips (Frankliniella occidentalis) are the largest pests of fruit-bearing vegetables in protected areas. Extremely polyphagous, short life cycle, high potential of reproduction and a large number of generations enables quick development of resistance that has been observed all over the world, and also in Croatia, where it was determined for pyrethroid and neonicotinoid preparations on all tested populations, and only some of the tested populations were sensitive to the active substance - spinosad. The main goal of the study is to determine the different sensitivity of adult forms of Western flower thrips to the active substances from the pyrethroids, neonicotinoids and spinosin groups. During 2019, removing pepper and cucumber plant parts, adult forms of Western flower thrips across the four counties were collected from nine localities, and testing was performed according to IRAC Test Method No. 10. During the studies, the treated population of Western flower thrips were resistant on eight sites to the active substance lambda-cyhalothrin. High abamectin resistance was determined at almost all locations, only the population of „Ferovac“ site was being resistant in some places. Populations of Western flower thrips were resistant to the active substance spinosad, only the population of „Mlinište 1“ (cucumber) was highly sensitive. Due to insufficient efficiency of permitted preparations, the suppression of the Western flower thrips can only be carried out in its integrated production and / or integrated vegetable protection