Effects of Neem (Azadirachta indica) seed and Turmeric (Curcuma longa) rhizome extracts on aphids control, plant growth and yield in okra

Abstract

The use of synthetic pesticides to control pests and increase crops yield is a common practice, but they cause several environmental and health problems. Therefore, there is a need to explore alternative approaches to reduce the sole dependence on synthetic pesticides. The present study was conducted to screen the extracts of Neem seed and Turmeric rhizome for pesticidal activities against okra pests (aphids). Experiments were conducted in field with four plots. One plot was kept as a control (unsprayed) and one was sprayed with synthetic pesticides, one with Neem seeds extract and one with Turmeric rhizome extract. The effect on number of pests, plant growth and yield was observed at regular intervals. A significant reduction in pests was recorded in all treatments as compared to the control. Neem seed extract was more effective than Turmeric rhizome extract as revealed by a 73% decrease in aphids by Neem extract in comparison to 54% by Turmeric extract after last application. Both the extracts were found to be more effective than the synthetic pesticides in controlling okra pests. Both the extracts had stimulatory effects on okra growth and yield. For example, the total yield of plots sprayed with Neem (53.3 kg plot-1) and Turmeric extract (47.7 kg plot-1) was higher than the yield of control plot (33.8 kg plot-1) and plot sprayed with synthetic pesticides (39 kg plot-1). It is concluded that Neem and Turmeric extracts can be used as alternative of synthetic pesticides for controlling pests attacks in okra.