SUPPRESSION OF MELOIDOGYNE INCOGNITA IN LYCOPERSICON ESCULENTUM WITH AM FUNGI AND PLANT EXTRACTS

Crop losses inflicted by nematodes are becoming one of the major limiting factors affecting plant growth and yield. Tomato is a highly susceptible crop to root knot disease caused by the nematode Meloidogyne incognita. The prolonged and overuse of chemical pesticides has resulted in several ill effects such as health hazards, ecological imbalances, development of resistance in pests, resurgence of pests, emergence of newer pests and environmental pollution. All these factors led to a search for safer and more compatible alternatives among which natural products are of first importance. A number of plant species possesses nematicidal compounds. Arbuscular Mycorrhizal Fungi (AMF) provide nutrition to the plant by sequestering the nutrients and water from the soil and translocating them to the plant and in return get carbon from the plants. They have also been reported to reduce the infestation of root-knot nematodes on vegetable crops. Therefore, a study was conducted to evaluate the potential of AMF along with five botanicals namely Azadirachta indica, Carica papaya, Ocimum sanctum, Ricinus communis and Tagetes patula, in reducing the M. incognita infestation in tomato (Lycopersicon esculentum var. Pusa Ruby) and results pertaining to the effect of these on plant growth and nematode population were collected. The integration of plant extracts with AMF resulted in reduced nematode multiplication and increased tomato plant growth and yield. The combinations significantly increased the mycorrhizal colonization and uptake of mineral nutrients such as N, P and K by plants. The best results, pertaining to AM root infection, nematode reproduction and plant growth and yield were obtained with the combination of AMF and O. sanctum.