Endomycorrhizal Associations of Acacias in Nurseries and Plantations of Indian Arid Zone

Abstract

Most woody plants depend on mycorrhizal fungi for their survival. Among the different mycorrhizal fungi, Vesicular-Arbuscular Mycorrhizal (VAM) fungi are widely distributed in varied ecosystems including arid and semi-arid deserts and associated with many plant species. An intensive survey was conducted to study the status of VAM fungal associations in Acacia spp. viz., A.nilotica sub species indica and A.tortilis sub species raddiana of various forest nurseries and plantations in arid zone of Rajasthan. The extent of VAM colonization in roots and spore populations in rhizosphere soils were quantified. Variation in per cent root colonization and number of VAM propagules in the rhizoshpere of both nursery and plantation samples was observed. Also, mean number of VAM propagules and per cent root colonization were greater in plantation samples than in nursery samples. Spores from the rhizosphere soils were isolated and tentatively identified as different species of Glomus, Gigaspora and Sclerocystis genera of endomycorrhizal fungi. Among these genera, Glomus is dominant in the rhizosphere of both the tree species screened. The most predominant VAM fungi were multiplied for future nursery inoculations.