Eggplant Integrated Pest Management AN ECOLOGICAL GUIDE

__________________________________________________________________________________Major Diseases of EggplantLife cycle of Meloidogyne rootknot nematodes(from: Kerruish et al, 1994)Importance - plant compensation - physiological impactGiven the very broad host plant range and the fact that these nematodes live in the soil, they are verydifficult to control once present in the field. When temperature and humidity are favorable, nematodepopulations can build up in time and this may increasingly result in crop damage.As a result of nematode infestation, the plants secondary root production is reduced which means thatthe uptake of water and nutrients will be interrupted. This reduces growth and production capacity ofplants. Plants can compensate for some injury by producing new roots but it depends on how muchinjury occurs if this will result in yield loss.Natural enemies/antagonistsThe action of certain species of fungi that attack nematodes has been studied for many years. Onefungus, Arthrobotrys irregularis, has proven successful in the control of rootknot nematode. The successof using this fungus depends largely on how well the fungus is able to establish itself within the soil.Another fungus, P. lilacinus, has been reported to control rootknot nematode. This fungus also controlsthe potato cyst nematode in the Philippines. In the Philippines a fungus was isolated from the soil knownas “Bioact strain 251”. A commercial formulation called “Bioact” containing spores of this fungus wasdeveloped. Bioact is very effective against all stages of plant parasitic nematodes, including rootknot(FAO – Dalat report (V. Justo), 1998).Another fungus, Myrothecium verrucaria, is an antagonist that occurs naturally in soils. A commercialstrain has been isolated in the USA and it is sold as “DiTera”, a powder formulation containing spores of136Eggplant Ecological Guide