Post Harvest Control of Tomato Fruit Rot Caused by Fusarium solani With Extracts of Azadirachta indica

Fusarium Solani is an important rot-causing organism of tomato fruit in storage. Alcohol and water extracts of bark, rootand leaves of the neem plant (Azadirachta indica) were tested against the pathogen both in vitro and in vivo. The alcoholextract of different parts, especially the bark of the plant, gave the highest growth inhibition of the fungus in culture andin checking rot development in the tomato fruits. Spraying the tomato fruits with the extracts before spray-inoculatingwith the spore suspension of the pathogen gave a better control of the rot disease than when the tomato fruits were sprayinoculatedwith spore suspension before spraying with the extract. The extracts from neem plant, especially the bark,could be used by farmers to control the rot of tomato fruit caused by Fusarium solani in storage. KEY WORDS: tomato fruit, Fusarium solani, Azadirachta indica, in vitro, in vivo Résumé Fusarium solani est un micro-organisme qui provoque la plus grande pourriture des fruits de la tomate lors de leur stockage.Les extraits à l'alcool et à l'eau, obtenus de l'écorce, de la racine et des feuilles de Neem (Azadirachta indica) ont été testéscontre ce pathogène à la fois in vitro et in vivo. L'extrait à l'alcool de différentes parties de la plante, et plus particulièrementl'écorce a provoqué l'inhibition la plus élevée de croissance tant dans la culture du champignon que dans le test dedéveloppement de la moisissure des fruits de tomate. La pulvérisation des fruits de tomate au moyen des extraits deneem avant l'inoculation de la tomate avec les spores du pathogène en suspension a donné un meilleur contrôle contre lamaladie de pourriture, plutôt que quand les fruits étaient préalablement inoculés avec la suspension de spores puispulvérisés avec l'extrait de la plante. Les extraits de la plante de neem et spécialement ceux obtenus de l'écorce pourraientavantageusement être utilisés par des paysans pour contrôler la pourriture du fruit de tomate provoquée par Fusariumsolani lors du stockage de la tomate. Mots-clés: fruit de tomate, Fusariurn solani, Azadirachta indica, culture in vitro, culture in vivoDiscovery and Innovation Volume 15 Number1/2 June (2003) pp. 83-8

Eficácia de extratos de nim para o controle do oídio do feijoeiro Effectiveness of neem extracts in controlling the powdery mildew of bean plant

O nim, Azadirachta indica, vem sendo estudado nos últimos anos para o controle de fitopatógenos. O objetivo deste trabalho foi avaliar o efeito do óleo, do extrato de sementes e do extrato de folhas de nim no controle do oídio do feijoeiro, em casa de vegetação. Uma formulação comercial de óleo emulsionável de nim foi testada em concentrações entre 0,25 e 2,0%, em aplicações antes ou após o surgimento dos sintomas da doença. O extrato de sementes foi produzido em laboratório por meio da trituração das sementes em água destilada, sendo pulverizado 48 horas antes ou 24 horas após a inoculação do patógeno. Avaliou-se, após o surgimento dos sintomas, a eficiência de uma formulação comercial de extrato de folhas, nas concentrações de 0,25 e 0,5%. Verificou-se que o óleo de nim foi eficiente para o controle da doença quando aplicado antes ou depois do surgimento dos sintomas. O extrato de sementes controlou a doença nas três concentrações testadas. Por outro lado, o extrato de folhas não foi eficiente no controle do oídio do feijoeiro.<br>The neem, Azadirachta indica, has been studied in the last years for the use in controlling plant pathogens. The objective of this work was to evaluate the effect of the neem oil, seed kernel extract and leaf extract on the control of the powdery mildew of the bean plant under green house conditions. The emulsified neem oil was tested for concentrations between 0.25 and 2.0% and sprayed before or after the appearance of the symptoms of the disease. The seed kernel extract was produced under laboratory conditions by grinding the kernels in distilled water, which was sprayed 48 hours before or 24 hours after the inoculation of the pathogen. It was also evaluated the efficiency of a commercial leaf extract at the concentrations of 0.25 and 0.5% which was sprayed after the appearance of the symptoms. The results of this work showed that the neem oil was efficient in the control of the disease when applied before or after the appearance of the symptoms. The seed kernel extract controlled the disease at the three tested concentrations. On the other hand, the leaf extract was not efficient in the control of the powdery mildew of bean plant