Cytotoxicity and Nematicidal Potential of Leaf Extracts of <em>Adansonia digitata</em> and <em>Khaya senegalensi</em>s on Root Knot Nematode (<em>Meloidogyne incognita</em>) Associated with Cabbage

Abstract

Purpose: Cabbage, an indispensable vegetable is often plagued by Meloidogyne incognita, a circumstance which lessens yield. Extracts of Khaya senegalensis and Adansonia digitata were appraised for possible nematicidal activity to check the menace of M. incognita sequel to the undesirable effect of synthetic nematicides in the environment. Research Method: Leaf materials were extracted in organic and aqueous extracts. The extracts were used as soil admix at 0, 150, 200 and 250 g/Kg soil, in a randomized complete block design experiment. Carbofuran a synthetic nematicide served as positive check for the extracts. Data was taken on vegetative growth, yield and nematode population. Lethality of the various extracts to brine shrimp larvae was also assessed. Findings: The aqueous extract was not as productive as the ethanol and methanol extracts. A. digitata extracts demonstrated weak nematicidal activity as against what was observed in cabbage plants treated with K. senegalensis extracts. Cytotoxicity evaluation of the organic and aqueous extracts of A. digitata indicated that the methanol extract expressed weak cytotoxicity (500 µg/ml - 1000 µg/ml), while the aqueous and ethanol extracts were not toxic to the brine shrimps (LC50 >1000µg/mL). K. senegalensis extracts were active against brine shrimp larvae with LC50 values <1000µg/mL The methanol and ethanol extracts demonstrated strong cytotoxicity with LC50 values <100µg/ml. Extracts from K. senegalensis significantly (p=0.05) increased the vegetative growth of cabbage plants. Originality/ Value: These results signify that the species have a probable use in the bio-pesticide industry, without any toxicity as the synthetics.