Cotton flea beetles, Podagrica spp. (Col., Chrysomelidae), and leaf roller, Sylepta derogata F. (Lep., Pyralidae), cause in Togo severe damage to leaves of okra plants and other species of the Malvaceae family, including cotton. Hence field trials were conducted in 1981–82 in order to investigate the efficacy of crude methanolic extracts of neem leaves and seed kernels and to compare it with that of a standard insecticide, deltamethrin.
It was found after 6 sprayings at weekly intervals that the number of feeding holes in leaves caused by cotton flea-beetles and leaf rolls caused by larvae of S. derogata on okra plants were distinctly reduced by all concentrations of the methanolic neem extracts compared to control plants. Also a higher yield of undamaged okra pods was recorded in the neem-treated plots (4–5 t/ha) which was almost twice as much as that of untreated plots (1.5–2.5 t/ha).
Cotton flea beetles, Podagrica spp. (Col., Chrysomelidae), and leaf roller, Sylepta derogata F. (Lep., Pyralidae), cause in Togo severe damage to leaves of okra plants and other species of the Malvaceae family, including cotton. Hence field trials were conducted in 1981–82 in order to investigate the efficacy of crude methanolic extracts of neem leaves and seed kernels and to compare it with that of a standard insecticide, deltamethrin.It was found after 6 sprayings at weekly intervals that the number of feeding holes in leaves caused by cotton flea-beetles and leaf rolls caused by larvae of S. derogata on okra plants were distinctly reduced by all concentrations of the methanolic neem extracts compared to control plants. Also a higher yield of undamaged okra pods was recorded in the neem-treated plots (4–5 t/ha) which was almost twice as much as that of untreated plots (1.5–2.5 t/ha).
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