COMMERCIAL USE OF AM FUNGI (AMF)

Although the separation or isolation of AMF is easy, but difficult to culture in the laboratory where it did not grow with the symbiotic association. So far, AMF thrives best in a natural habitat with the association in higher plants. In most of the cases, mycorrhizal fungal propagules are used to produce commercial symbionts in a noil-sterile medium, either soil or some other non-sterile substrate or organic waste. The growth of the mycorrhizal inoculums was veiy slow' in the laboratory as compared to many other microorganisms and propagule numbers (spores, hyphae, and mycelium); in many products, which reflects their presence was in low concentration. To establish AMF in the field, therefore, requires large volumes/weights of inoculums, which are veiy costly. Hence, the production of AMF in the laboratory and its dispersal to the fanners at the commercial level did not suffice the cost of inorganic phosphate fertilizers. In some laboratories, scientists have developed AMF inoculums efficiently in a gel-based earner, which is highly concentrated, but these products are yet to come into the market as commercial products. Such types of techno logical breakthroughs are required for AMF proliferation/propagation to be realistically used in the agriculture production system. In almost all soils, mycorrhizae are present in high or low amount in association with important field and horticultural crops. Hence, the use of AMF symbionts/inoculums may give a boost for production by maintaining soil and plant health.

In the past four years, worldwide fertilizer cost (total) has gone up to more than 400%, and fanner's dependency on the use of chemical fertilizer is dwindling. The cost of DAP, nitrogen, and other fertilizers and combined costs per acre now' exceed, and fanners are hying to find a viable alternative to reduce their fertilizer and water costs (up to 30%). For them, AMF could be a good option. The market intervention of true to type mycorrhizal products could change the science and fanners' interface with profit and soil health for sustainable agriculture, which is long been expected by the country like India and other counties of arid and semi-arid w'orld.

CONCLUSION

Of late, the use of inorganic/synthetic fertilizer in agriculture has been substantially increased across the world and across the different fanning communities to mitigate the glowing demand for food for people. Due to the over demand for fertilizers and plant nutrients, there are escalating cost of inputs in agriculture production system. It has been found that excessive use of fertilizers resulted in a worse impact on soil, water, ecosystem, and total environment. In such a situation, the concept of using AMF as a bio-fertilizer is cost-effective, energy-saving, eco-, and enviromnent-fiiendly, and promising and perspective for rural and poor fanners of the developing countries. The practical utility of AMF in agriculture food production system is well established. To keep the soil healthy and fertility, status intact, and augment of production by supporting sound plant health through the decomposition of organic matter, AMF could be successfully used in sustainable agriculture or low externally input agriculture. In India, mycorrhizae are successfully used in fruit crops like apple, cheny, plum, citrus, banana, litchi, medicinal, and aromatic plants and grain crops like wheat, maize, pulses (mung) and oilseeds (sunflower and mustard). In addition to these, it is widely used for soil amelioration from cadmium toxicity through the cultivation of rapeseed. In Africa, Cassava is also one of the top crops, and AMF is well known for enhancing the yield and growth of the above-said crop. Cassava, the crop of Columbia, is a major staple for nearly a billion rural poor living in more than 100 countries, from South America-Africa-Asia (Brazil to Nigeria to Thailand). Producing more cassava means poor communities can eat more food or give livelihood security to the rural poor. In senriarid areas, fanners are suffered from low’ yield and paying more price to fertilizers. Scientists are trying to get more yields or grow' more crops for the sustainable manner in the underexploited areas through the use of soil microorganisms, especially using different kinds of mycorrhizae in the agriculture production system.

KEYWORDS

• • AM fungi
• • arid and semi-arid climate
• • carbon assimilation
• • defense action
• • Glomus spp.
• • metabolism
• • mycorrhizae
• • nodulation
• • nutrient uptake
• • phosphate acquisition
• • water uptake