Physiologie, Morphologie und Gesundheit von Mykorrhizierten Pflanzen

Summary

The formation of vesicular arbuscular mycorrhiza (VAM) is a tightly interlacement of fungi and plant structures which resulted in the development of dual organsims. This leads in plants to physiological, bioehemical and morphological ehanges. In root, it should be differentiated between the local and systemic efFect of mycorrhiza, in shoot the effects could be systemic only. These ehanges are often connected with increased resistance to root pathogens and increased suseeptibility to shoot pathogens. As it has been shown with the infection of linseed by Oidium lini, in spite of the increased suseeptibility the mycorrhizal plants suffered less than non mycorrhizal plants (induced tolerance). However, at high infection pressure the effects of mycorrhiza are not efficient and reliable enough to reduce losses at the level of economic threshold. Nevertheless, mycorrhiza achieves a notable contribution for the plant health, since mycorrhizal plants are more produetive than non mycorrhizal, if they grow under the influence of impairing factors. The mechanisms for this are yet not well understood, however ehanges in the phytohormone balance may play a determining role.