Ovicidal and adulticidal effect of acaropathogenic fungi, neem oil and new acaricide molecules onTetranycus urticae Koch

摘要

The relative toxicity of two acaropathogenic fungi (Hirsutella thompsonii and Beauveria bassiana), neem oil and three new acaricide molecules viz., fenazaquin 10 EC, spiromesifen 240 SC and diafenthiuron 50 WP to two-spotted spider mites (egg and adults) were evaluated against a standard check and untreated control under laboratory conditions. 24 hours after treatment, fenazaquin 10 EC excelled in ovicidal activity with a mean egg mortality of 40.81 per cent. The next best treatment was spiromesifen240 SC which recorded 15.17 percent egg mortality. Both fenazaquin 10 EC and diafenthiuron 50WP exhibited 100 per cent adult mortality within 24 hours of treatment application. After 72 hours, all the treatments except B. bassiana caused significantly high egg mortality. Neem oil (41.00 per cent) and H. thompsonii (31.98 per cent) emerged as the next best candidates with respect to adult mortality, while spiromesifen 240 SC recorded the lowest adult mortality of 3.40per cent.