Ertrag und Wurzelkolonisation mit arbuskulären Mykorrhiza- Pilzen von organisch oder mineralisch gedüngtem Weizen auf trockenem, sandigen Boden

Summary

We investigated wheat yield and arbuscular mycorrhiza (AM) fungal root colonization
and spore formation in response to fertilization, either with high or low amounts of
mineral fertilizer or cattle manure since 27 years. At low rates there was no difference
in yield between minerally and organically fertilized plants. High rates of mineral
fertilizers reduced yields. Reasons can be that either the high nitrogen availability was
less effectively used for grain development of minerally fertilized plants, or the mineral
fertilization rendered the plants more sensitive towards drought stress. The extent of
AM fungal root colonization appeared to depend on the plant P nutritional status rather
than the type of fertilizer applied. The lower fertilization showed higher rates of AM
root colonization. The number of AM spores, however, was higher in organically
compared with minerally fertilized soil, indicating that organic fertilization increased
reproduction of these beneficial microbes under dry soil conditions.