Efficacy of certain pesticides against red spider mite Tetranychus cinnabarinus Koch infesting okra.
The efficacy of dicofol 18.5 EC (0.02%), propargite 57 EC (0.08, 0.11 or 0.17%), monocrotophos 36 SL (0.05%) and NSKE [neem seed kernel extract] (5.0%) against T. cinnabarinus infesting okra (cv. Super Anamika) was evaluated near Ghaziabad, Uttar Pradesh, India, from April to July 2003. The mite appeared in May and its population gradually increased. All treatments significantly reduced the mite population up to 7 days after treatment. Mite mortality at 7 days after the initial spraying was greatest with propargite at 0.17 and 0.11% (49.1 and 53.37 per 3 leaves, respectively) and dicofol (56.7 per 3 leaves). The mite population started to increase again at 7 days after the initial spraying. At 15 days after the first spraying, a second spray was given. The mite population at one day after the second treatment ranged from 30.19 (propargite 57 EC at 0.17%) to 42.94 (NSKE). After the second spray, all treatments maintained the mite population at significantly low levels up to 15 days. T. cinnabarinus completely disappeared during the rainy season.