Mycorrhizas in Forest Tree Health
Mycorrhizas impart fungus-root associations and a true symbiotic relation between fungi and plant roots, which is very close to that of nodular microbes (actinomycetes and bacteria) in legume crops. This type of association boosts both the allies (i.e. the fungus and its specific host plant) to be reciprocally benefited by each other, as the fungus absorbs hydrogenous nutrients and edaphic factors from soil and channelizes the same to the plant system, and in turn synthesis its nutrition (carbohydrates and photosynthates) from the host plant for its growth and multiplication.
There is now plenty of proof to support the mutual declaration that most tree species in normal ecosystems have mycorrhizal associations. Evidence about the global distribution of tree plants with diverse populations of mycorrhizal relations is used to establish associations with the major abiotic factors (water, temperature) which control the distribution pattern of forest trees, and also to extend more restricted edaphic factors. Environmental inferences of mycorrhizal associations in forest ecosystems and the role of soil or ecological influences, mycorrhizal fungus physiognomies or host plant belongings in an individual manner or in groupings are considered accordingly. Factors which can affect the existence mycorrhizal associations are (a) root characteristics, (b) edaphic or ecological factors, (c) soil biodynamics, (d) soil commotion and (e) tree host-fungus compatibility, thus, we address the overall ecological dynamics in this review. Environmental themes on ecological aspects have been discussed in this chapter which include (a) mycorrhizal phenology, (b) influences responsible for variable grades of mycorrhizal reliance in host trees, (c) the implication of mycorrhizal hyphae in soil, (d) nutritional rivalry connecting mycorrhizal and non-mycorrhizal tree species and (e) mycorrhizal connections associating effluence and additional stresses, the rhizosphere, soil possessions and so on. The population dynamics of mycorrhizal fungi and the impact of their relations on forest tree ecology also form a comprehensive discussion.
KeywordsArbuscular Mycorrhizal Fungus Arbuscular Mycorrhizal Arbuscular Mycorrhiza Ectomycorrhizal Fungus Mycorrhizal Association
Ajit Varma is thankful to the Department of Science and Technology and the Department of Biotechnology for partial financial funding, and to DST-FIST for providing a confocal microscope facility.
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