Development Durations, Colonization and Insecticide Efficacy of Leaf Mite, <i>Oligonychus oryzae</i> Hirst on Rice

Abstract

Oligonychus oryzae is an economic mite pest infesting rice crops in India and other Asian countries. This study examined the duration of development instars at 20 °C – 35 °C , level of colonization of mites in eight commercial rice varieties viz., ADT 36, ADT 43, ADT 45, IR 50, CO 47, ASD 16, ADTRH 1 and TN 1 and assessment of efficacy of five insecticides against O. oryzae during 2005 and 2006. The duration of development from egg to adult lasted 8.33±0.20 days at 35 °C. ASD 16, ADTRH 1 and CO 47 were moderately resistant to leaf mite; ADT 45, TN 1, IR 50 and ADT 36 were moderately susceptible; ADT 43 was the most susceptible variety. Among the chemicals tested, Abamectin 1.8 EC was found to be the most effective DOI: http://dx.doi.org/10.4038/tar.v21i1.2584Tropical Agricultural Research Vol. 21(1): 30-38 (2009)

Keywords

• oligonychus oryzae
• leaf mite