Spore density and diversity of Arbuscular mycorrhizal fungi in medicinal and seasoning plants

Arbuscular mycorrhizal fungi (AMF) set mutualistic symbiosis with most plants. Understanding this association and meet the diversity of AMF in both the medicinal and the seasoning herbs is very important, since these plants have increasingly contributed to improving the quality of human life. The aim of this study was to assess the spore density, taxonomic diversity, and root colonization by AMF in experimental beds of rosemary (Rosmarinus officinalis L.), nasturtiums (Tropaeolum majus), mint (Mentha crispa L.), boldo (Peumus boldus), oregano (Origanum vulgare) and chamomile (Matricaria chamomilla), all planted in the Medicinal Plant Nursery of the Paranaense University UNIPAR, Umuarama – PR. Soil samples (0 to 10 cm depth) and plant roots were collected in two periods, June and November 2011. Colonization of plant roots by AMF ranged 17 to 48%. The rosemary treatment was highly responsive to the sampling periods, with only 17% of root colonization in June compared with 48% in November. The AMF spore density was higher in June than in November for all species of plants studied. Among the AMF identified within this study, the dominant genus was Glomus sp., followed by Acaulospora sp. in all plants analyzed. Greater knowledge over diversity and density of AMF spores can strongly contribute to the sustainable management of nutrition for medicinal and seasoning plants, particularly on phosphorus supply.