MANJUNATH, A.CHAITHRA, B. M2017-08-012017-08-012015-07-10Th-110135http://krishikosh.egranth.ac.in/handle/1/5810026989A greenhouse investigation was conducted to determine the effect of biochar application on effectiveness of VAM symbiosis in Leucaena leucocephala at different nutrient levels. This investigation consisted of 24 treatments resulting from factorial combination of two levels of biochar, six levels of nutrient and two levels of Glomus aggregatum inoculation. Mycorrhizal colonization in roots of Leucaena was significantly reduced at higher nutrient levels. The phosphorus content in shoot as well as root and total phosphorus uptake increased significantly in plant colonized with VAM fungus at all levels of nutrient amendment, irrespective of biochar application. The inoculation of soil with VAM fungus increased biomass production by Leucaena at all nutrient amendment at both levels of biochar application. Leucaena plants grown in soil amended with biochar produced less biomass than those grown in soil without biochar amendment at all levels of nutrient application. The linear regression analysis of data indicates the effect of nutrient levels on total biomass and total phosphorus uptake is more pronounced than that of biochar levels. The results of this investigation exemplifies the significance of optimizing nutrient application rate as well as level of biochar amendment in order to derive maximum benefit from VAM symbiosis.ennullThesis