ISSN:
1573-5036
Keywords:
Fine roots
;
Forest trees
;
Host-dependence of mycorrhizal fungi
;
Mycorrhizal successions
;
Provenance effects
;
Root biomass
;
Root/shoot ratios
;
Soil moisture
;
Spatial and temporal distribution of roots
;
Structural roots
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Summary Many factors affect root development. While considering seasonal and other abiotic influences, the major, genetically controlled differences, attributable to provenance (site of origin), should not be ignored. Site preparation, involving the development of drainage channels and the inversion of some soil horizons, leads to an increasingly complex milieu for root development with a changed availability of nutrients and the restriction of root growth to largely linear configurations. Fruitbodies of sheathing mycorrhizal fungi do not occur at random. Their distribution, in time and space, is host-dependent: there is strong evidence of a succession. Together, fruitbody observations and controlled inoculations suggest that there are functional differences between fungi occurring in the early stages of the mycorrhizal successione.g. species ofHebeloma andLaccaria, and those occurring at a later stagee.g. species ofAmanita. White both groups of fungi readily form sheathing mycorrhizas with tree seedlings in axenic conditions, only early-stage fungi form mycorrhizas with seedlings growing in unsterile soils. The difference seems to be related to the occurrence of other soil microbes; it highlights the need to adopt an epidemiological approach to a three membered biological complex of host, mycorrhizal fungi and other soil microbes. For the future the functional relationship between fine roots and tree growth, and the effects of changes in the soil environment, should be extended to include mycorrhizas and their external wefts of strands and hyphae.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02182637
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