Superior differentiation of arbuscular mycorrhizal fungal communities from till and no-till plots by morphological spore identification when compared to T-RFLP

In our experiments we intended to document the impact of tillage on arbuscular mycorrhizal (AM) fungal communities under temperate climate conditions and intensive agriculture in a Luvisol of a fertile Loess area in Saxony (Germany). AM fungal community structure and diversity have been examined in a long-term field experiment in plots subjected to conditions of intensive agriculture with continuous 3-year rotation of winter wheat, winter wheat and sugar beet and managed by till and no-till treatments for thirteen years. AM fungal diversity was assessed by sequence analysis and terminal restriction fragment length polymorphism (T-RFLP) using the nested PCR-primers LR1/FLR2 and FLR3/FLR4 as well as by morphological spore identification. While both analyses resulted in essentially similar pictures of fungal community composition and of negative effects of tillage for AM fungal diversity, morphological spore identification allowed a considerable better differentiation of fungal taxa and a more sensitive detection of changes in community composition and diversity when compared to molecular methods.