Pathogenicity of two entomopathogenic fungi and toxicity, oviposition deterrent, and repellency of two essential oils on Eutetranychus orientalis

Document Type : Original research articles

Authors

1 Fruit Trees Mites Dept., Plant Protection Research Institute, ARC, Dokki, Giza, Egypt.

2 Fruit Trees Mites Dept., Plant Protection Research Institute, ARC, Dokki, Giza, Egypt

3 Bio-Insecticide Production Unit, Plant Protection Research Institute, Agricultural Research Center, Giza, Egypt

Abstract

Eutetranychus orientalis (Klein) (Tetranychidae) is a worldwide polyphagous mite causing economic damage to several crops. A laboratory experiments was carried out to evaluate the pathogenicity of two entomopathogenic fungi, Beauveria bassiana (Balsamo) Vuillemin and Metarhizium anisopliae (Metschnikoff) Sorokin, on E. orientalis at three spore concentrations (106, 107, and 108 conidia ml-1). Probit analysis indicated that B. bassiana was significantly effective and more virulent (LC90 = 1.34×108 conidia ml-1) than M. anisopliae (LC90 = 2.46×1011 conidia ml-1), with relative toxicity of 100: 0.2. Toxicity of two essential oils: neem (Azadirachta indica A.Juss. (Meliaceae) and caraway, Carum carvi L. (Apiaceae) against E. orientals was also evaluated at concentrations of 0.125, 0.25, 0.5, and 0.75%. Based on LC90, caraway oil caused higher mortality percentage of E. orientalis females than neem oil after 72 h (i.e., LC90 = 0.198 and 0.753%, respectively) with relative toxicity of 100: 26.30. Oviposition deterrent index increased as concentration increase. It was highest for caraway as 59.91 and 39.2% for neem at concentration of 0.75%. Repellency effect increased as oil concentration increase, and decreased as time increase. Environmentally suitable options for bio-control of E. orientalis might consider the obtained results.

Keywords

Files

Share

How to cite

Statistics