Arbuscular Mycorrhizal Dependency of Plants (original) (raw)

2016, IK International Pvt. Ltd.

Arbuscular mycorrhizal (AM) symbioses occur with more than 80% of land plants and are widely distributed in almost all the ecological range where plants grow. Mycorrhizal fungi as such are non-host specific but as reported, the preference and mycorrhizal dependency of plants may vary with the soil. It is known that phosphorus is a relatively immobile element in soil and its demand is much higher than its mobility. Other than phosphorus, AM fungi also help plants to capture micronutrients such as copper, zinc, Boron, etc. AM is said to be a key factor of plant establishment in different plant communities; plant growth and soil sustainability in nutrient poor soils. Several workers have worked on the mycorrhizal dependency of different plants which include weeds, agricultural, horticultural and forest crops. Parameters mainly used to determine MD is biomass, leaf phosphorous, phosphpous utilization of plants, root morphology, etc. Mycorrhizal dependency is the degree to which a plant is dependent on the mycorrhizal condition to produce its maximum growth or yield, at a given level of soil fertility. Even same plant with same VA fungi may vary on MD, according to some reports. Majority of the agricultural species are either obligate or facultative mycorrhizal. Most of the mycorrhiza dependent plant species show better result at lower P content. Increased soil P concentration depresses the mycorrhizal infection and also the intensity of infection which is reflected in the degree of MD of such plant species. However, totally dependent species may continue to derive benefit from mycorrhizal symbiosis irrespective of concentration of soil P.