EFFECT OF BOTANICALS AND SYNTHETIC INSECTICIDES ON INSECT PEST AND DISEASES OF MARIGOLD

The experiment was conducted in the National Horticultural Research Institute (NIHORT) Idi-Ishin, Ibadan to determine the efficacy of the botanicals and synthetic insecticide in controlling the pests and reducing the manifestation of diseases in Marigold. The experiment was arranged in a randomized complete block design (RCBD) with three replicates. Extracts from Chrysanthemum morifolli (garden mum) leaf extracts (100 g/litre), Tithonia diversifolia (tithonia) leaf extracts (200 g/litre), Azadirachta indica (neem) seeds extract (5 ml/10litres) and Cypermethrin (synthetic insecticide 5 ml/10litres of water) were applied as foliar sprays 2, 5 and 7 weeks after transplanting using a hand sprayer. The control plots were without botanicals or any insecticide application. Aphids and Alternaria blight were identified as the major insect pest and fungal disease. The number of aphids was significantly (P < 0.05) lower in the treated plots than in the control. However, of all the botanicals, Azadirachta indica (neem) seed oil extracts significantly reduced aphids population and disease incidence compared with the Tithonia diversifolia (tithonia) and Chrysanthemum morifolli (garden mum) leaf extract. The plant height, number of leaves, number of flowers and seed weight were significantly higher in plots sprayed with Cypermethrin and lowest in the control plots. In the result neem seed extract performed best among the botanicals and was comparable with cypermethrin in the plant height and number of flowers and the reduction in the percentage incidence of disease on marigold and could therefore be used as an alternative to cypermethrin in marigold production.