Screening of Different Substrate for Mass Production of AM Fungi and Their Interaction with N2 Fixer and Po4 Solubilizer on Growth and Yield of Finger Millet (Eleusine corocana L)

Application of Arbuscular Mycorrhiza (AM) to field crops has remained yet unresolved as AM fungi are obligate symbionts and cannot be cultured in the laboratory. At present soil based inoculum production and application as such to crops is in vogue. To ease the application procedure, this study was carried out to understand whether or not AM fungi inoculated at nursery level can serve as inoculum to transplantable crops in field. The experiment was conducted under glass house conditions to screen different substrates viz., Vermicompost, Farm Yard Manure, Tank silt for obtaining enhanced colonization and spore numbers. The vermicompost enhanced the colonization and spore numbers. Further, study was carried out to determine the colonization interval of nursery inoculated finger millet seedlings. The root colonization was observed after 20 days of sowing. The colonization percentage increased as days increased. At 30 days interval, root colonization was increased to >50 %. The seedlings thus colonized were used for transplantation to study the interaction effects with Nitrogen fixing and Phosphate solubilizing bacteria on growth and yield of finger millet under glass house conditions. The results showed that the AM colonized seedlings treated with N2 fixer and Phosphate solubilizer during transplantation, significantly increased the growth, yield and root colonization compared to uninoculated plants. Thus, this study revealed the possibility of application of AM fungi at nursery level to transplantable crops.