POTENCY OF Azadirachta indica AND Tithonia diversifolia BASED BIO-PESTICIDE ROOT DIPS IN THE MANAGEMENT OF ROOT-KNOT NEMATODE INFECTION IN TOMATO (Solanum lycopersicum L.)

Abstract

Root-knot nematodes, Meloidogyne species, remain very important economic threats to tomato cultivation. Screen-house experiment was carried out in 2014 and repeated in 2015 to test the efficacy of two plant-based pesticide slurries from Mexican sunflower (Tithonia diversifolia) and Neem (Azadirachta indica) at three different concentrations (0%, 0.5% and 1%), singly or in combination on root-knot nematodes disease on tomato. There were six treatments which included Roma VF tomato seedlings dipped for five minutes in Neem at 0%, 0.5%, and 1%, Tithonia at 0%, 0.5% and 1% slurries and transplanted in 7litrepots containing 6 kg sterilized soil. Treatments were arranged in Completely Randomized Design and replicated Eight times. At four weeks after transplanting, each treatment was inoculated with approximately 5000 eggs of Meloidogyne incognita except the control. Data were collected at 2, 4, 6 and 8 Weeks After Inoculation (WAI) on plant height, stem girth, leaf area and number of leaves. At 60 days after inoculation, the experiment was terminated to determine the final nematode population. Data collected were subjected to Analysis of Variance. Statistically different means were separated using Duncan Multiple Range Test (DMRT) at 5% level of probability. Results showed that dipping roots of Roma VF tomato seedlings slurries made from powdered leaves of T. diversifolia and A. indica for 5 minutes at 1% concentrations significantly reduced Meloidogyne incognita populations between 4% and 35% compared with the control in 2014 and 2015.In 2014, there was a significant reduction in Meloidogyne species populations in plant treated with Tithonia at 1% (3.84%) compared with Neem at 1% (16%). In 2015, plant treated with Neem at 1% reduced (p≤0.05) egg number from 50% to 35% while Tithonia at 1% caused significant (p≤0.05) reduction from 50% to 24%.The study concluded that, although, both Tithonia diversifolia and Azadirachta indica can be used to suppress nematode population and improve the Roma VF tomato plant growth. T. diversifolia proved to be more effective in nematode management strategy.