In vitro sensitivity of Alternaria solani to conventional fungicides and a biofungicide based on tea tree essential oil

Abstract

A study of in vitro sensitivity of five Alternaria solani isolates to cooper-oxychloride, chlorothalonil, difenoconazole, pyraclostrobin and a biofungicide based on tea tree essential oil was carried out. The isolates were obtained from infected tomato leaves collected from five different locations in Serbia. The tested isolates showed the highest sensitivity to pyraclostrobin with EC50 values ranging from 0.0014 to 0.0041 μg ml-1. The EC50 values of difenoconazole were 0.018-0.037 μg ml-1, chlorothalonil 2.99-4.54 μg ml-1, and cooper-oxychloride 13.27-15.63 μg ml-1. All tested A. solani isolates were the least sensitive to tea tree oil (1323.97-3307.08 μg l-1).

Ispitivana je osetljivost pet izolata Alternaria solani u in vitro uslovima na bakar-oksihlorid, hlorotalonil, difenokonazol, piraklostrobin, kao i etarsko ulje čajnog drveta. Izolati su dobijeni iz zaraženih listova paradajza sakupljenih sa pet lokaliteta na teritoriji Republike Srbije. Ispitivani izolati su pokazali najveću osetljivost na piraklostrobin, sa EC50 vrednostima u intervalu od 0,0014 do 0,0041 μg/ml. Vrednosti EC50 za difenokonazol su bile od 0,018 do 0,037 μg/ml, hlorotalonil 2,99-4,54 μg/ml i bakar-oksihlorid 13,27-15,63 μg/ml. Svi ispitivani izolati A. solani su ispoljili najmanju osetljivost na etarsko ulje čajnog drveta (1323,97-3307,08 μg/ml).