Relationship of arbuscular mycorrhizal fungi and Azotobacter with plant growth, fruit yield, soil and leaf nutrient status of mango orchards in north-western Himalayan region of India

Abstract: The present investigation was undertaken with the objective to find out the nutritional status of mango orchards cv. Dashehari located in north- western Himalayan region of India and to establish the relationship of soil microflora especially, arbuscular mycorrhizal (AM) fungi and Azotobacter with growth, fruit yield, and soil and leaf nutrient contents. The study revealed that the correlation between AM spore population and shoot extension growth, leaf area, fruit yield, available Cu and Zn content and leaf N, P, Cu, Zn and Mn contents was found to be positive and significant, whereas, the relationship with soil as well as leaf K content was negative but significant. Azotobacter count was positively and significantly correlated with fruit yield, soil organic carbon (OC) and leaf Fe content, while, it was negative and significant with leaf K content. The relationship of per cent root colonization with soil OC and available N content of orchard soil was found to be positive and significant, and with shoot extension growth, leaf area, fruit yield, electrical conductivity, available P, K, Cu, Zn and Mn content and P, K and Cu contents of leaf, it was negative but non-significant.