Stress Tolerance Through Plant, Mycorrhizal Associations : Benefits of VAM mycorrhiza associations in alleviating drought, salinity and pathogenic plant infection

The unique morphological manifestations called " Mycorrhizae" represents one of the nature's most widespread phenomenon of symbiosis. VAM fungi largely help plants in both, nutrient mobilization and cycling through their extrametrical hyphae. VAM fungi increase the absorption of immobile elements in soil such as phosphorus, copper and zinc. Plants respond to the VAM fungi more in sites exposed to stress conditions such as drought, salinity. VAM fungi was also reported to reduce severity of plant diseases particularly diseases caused by soil- borne pathogens since mycorrhizal roots are more lignified than non-mycorrhizal roots. This resistance to pathogen is primarily due to improvement of host vigor and development and production of inhibitory substances. Because of these attributes, mycorrhizae are today considered an important component in the re-establishment of plants especially those plants growing under inhospitable sites such as sand dunes and other stressed locations. The objectives of this work are to identify VAM fungi widely colonizing plant roots under stress conditions to investigate the potential role of mycorrhizae for alleviating stress conditions.