Evaluation of nematicidal action of some botanicals on Meloidogyne incognita in vivo and in vitro

Eggmasses or larvae of Meloidogyne incognita were exposed to varying concentrations of neem leaf (fresh and dry), Borelia sp., groundnut leaf and garlic bulb. Neem leaf and garlic bulb extracts inhibited hatching of eggmasses and were lethal to larva. A comparative study of neem and garlic bulb extracts prepared at 20 % concentration and applied weekly at 25 ml per pot were carried out in the screenhouse. Each pot filled with 2 kg of pasturised soil was inoculated with 2 000 larvae of M. incognita by introducing 500 g of infested soil from tomato culture raised in the screenhouse. These extracts significantly reduced root-knot infection indices on tomato when compared to the control. However, garlic extract demonstrated greater potential than neem leaf extract in the control of root-knot infection of tomato in vivo.