Mycorrhiza in Agriculture and Industry

Abstract

Pot culture experiments were conducted in an acidic sandy loam soil with organic matter 20%, PH-5.3, available P-2.5mg/Kg, N2-6.8mg/Kg and K- 20mg/Kg, to isolate and multiply Vesicular Arbuscular Mycorrhizal spores in sterilized soil using Paddy (Oryza sativa) as host plant. Multiplied single spore culture of Glomus mosseae was used to study the effect of these mycorrhizae on two leguminous plants- Vigna unguiculata (cow pea) and Arachis hypogeae (ground nut), grown under soil based stressors like heavy metals, Pesticides, physiological stressors like drought salinity etc. The growth rate, NPK levels, biochemical constituents like chlorophyll, carbohydrates, reducing sugars, proteins etc, and the antioxidant enzymes, antioxidants etc and the level of proline were estimated. It was found that the stressors reduced the VAM fungal spores in the soil and thus lowered the percentage of mycorrhizal infection. There was a direct relation between the percentage of VAM infection and growth of host plants. Lower doses of heavy metals and pesticides did not affect the VAM colonization significantly, but higher doses of heavy metals and recommended dose of BHC reduced VAM infection significantly. It may be concluded that the proper selection of a VAM fungus enabled the host plants to survive even on adverse environmental conditions. The inoculation of mycorrhizal fungus along with other microorganisms like N2 fixing bacteria- Rhizobium, Phosphate solubilizing bacillus etc enabled the host plants to grow better. The tetra partite association of VAM fungus, Rhizobium, Bacillus in leguminous plants showed increased nutrient status and biochemical constituents. From this, we could be able to recommend VAM as a good biofertilizer and bioremediator.