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Methods of AM Fungal Inoculation
Since it has not been possible to culture AM fungi, alternate methods of plant inoculation have been practiced. Individual spores, soil sievings, in­fected roots or plants and soil from around the roots can be used for in­oculating fresh plants. However, these methods are subject to contamination with unwanted microorganisms and pathogens.

Growing plants infected with specific species of AM fungi in pots is currently one of the recognised practices not only to maintain the fungal germplasm on live roots but also to mass produce inoculum for pot and limited scale field experiments. For this purpose spores that look alike morphologically are isolated by means of glass capillaries from soil siev­ings and transferred to individual watch glasses.

The macarate can be directly used as inoculum by plac­ing it close to the roots (at the rate of 5-10 per cent of the potting mix) to about 2-5 cm below the soil level and watered periodically. Alternatively, seeds can be pelletted, air dried and sown.

There have been improvements in culturing AM fungi on plant roots by a system known as 'aeroponic culture', wherein roots are grown in a fine continuous mist of nutrient solution under aseptic conditions with the shoot system intact in open air to facilitate the production of high quality inoculum without contamination. The roots are checked for colonization by the specific AM fungus, macerated in a waring blender and used as inoculum