Influence of organic and inorganic additives to the substrate on the quality of AM fungal inoculum
Authors:   Center for Natural Biological Resources and Community Development (CNBRCD),  41 RBI Colony, Anand Nagar Bengaluru-560 024 Email: djbagyaraj@gmail.com, R. PRAVEEN , R. ASWIN , D.J. BAGYARAJ 
Published: December 2024

Abstract
The production of a good quality arbuscular mycorrhizal fungal (AMF) inoculum is essential for its application in sustainable agriculture. The system for producing AMF inoculum using vermiculite, Perlite, and soilrite mixed at 3:1:1 as substrate with the addition of nutrient solution is a well-known method of mass production. However, organic and inorganic amendments added to the substrate can stimulate colonization and sporulation of AMF and increase the overall quality of the inoculum. The present study was undertaken to improve the quality of AMF Funneliformis caledonius (earlier called Glomus caledonium) culture using selected organic and inorganic amendments (humate, chitosan, kaolin, bentonite, biochar, vermicompost and fermented cocopeat) added to the usual substrate. The results of the experiment revealed that the production of spores, infective propagules (IP) and per cent root colonization varied among the amendments. The increased spore numbers (66.5 and 62.5/g), root colonization (92 and 85%) and IP numbers were recorded in treatments amended with kaolin and biochar, respectively, each @10g/kg substrate. The system of inoculum production using substrate amended with 1% kaolin or 1% biochar favours the production of good quality inoculum of F. caledonius compared to the conventional method.
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