06-08-2013, 04:40 PM
VAM- Potential tool for disease management
ABSTRACT
VAM fungi colonize plant roots, ramify into the surrounding bulk soil and extend root depletion zone around the root system. They transport water and mineral nutrients from soil to the host plant while the fungal partner benefits from the carbon compounds manufactured by the host. Therefore, VAM fungi have pervasive effect on plant form and function. The establishment of VAM fungi in the plant root has been shown to reduce the damage caused by soil-borne plant pathogens with the enhancement of resistance in mycorrhizal plants. The effectiveness of VAM fungi in bio control is dependent on the VAM fungus involved as well as the substrate and host plant. VAM fungi generally reduce the severity of plant diseases to various crops suggesting that they may be used as potential tool in disease management. VAM fungi modify the quality and abundance of rhizosphere microflora and alter overall rhizosphere microbial activity. These fungi induce changes in the host root exudation pattern following host colonization which alters the microbial equilibrium in the myco-rhizosphere. Given the high cost of inorganic fertilizers and health hazards associated with chemical pesticides, VAM fungi may be most suitable for sustainable agriculture and also for increasing the yield of several crops through biocontrol of plant pathogens. Significant advances have been made in last two decades to understand the potential of mycorrhizal fungi in suppression of plant pathogens especially soil borne pathogens in wide range of fruits and vegetable host plants.