Seasonal dynamics of arbuscular mycorrhizal (AM) fungal community composition in three common mangrove plant species, namely, Acanthus ilicifolius, Excoecaria agallocha, and Rhizophora mucronata, from two sites in Goa, India, were investigated. In all three species variation in AM fungal spore density was observed. Maximum spore density and AM species richness were recorded in the premonsoon season, while minimum spore density and richness were observed during monsoon season at both sites. A total of 11 AM fungal species representing five genera were recorded. Acaulospora laevis was recorded in all seasons at both sites. Multivariate analysis revealed that season and host coaffected AM spore density and species richness with the former having greater influence than the latter. 1. Introduction Mangroves are a type of coastal woody vegetation that fringes muddy saline shores and estuaries in tropical and subtropical regions [1]. They are characterized by high levels of productivity and fulfill essential ecological functions, harbouring precious natural resources [2]. Mangroves have become the center of many conservation and environmental issues because of the beneficial effects they have on the coastal environment. Recent evidence suggests that growth of mangroves is limited primarily by phosphorus (P) availability as it is adsorbed and coprecipitated within carbonate-dominated environments [3]. Phosphate solubilizers, N fixers, and AM fungi are known to interact in the rhizosphere soils [4] where hyphae of AM fungi assist in accessing nutrients by extending beyond the root depletion zone [5]. These fungi also alleviate salt stress and aid physiological processes such as osmotic adjustment via accumulation of soluble sugars in root cells [6] and contribute to the nutritional status of plants [7]. They play a crucial role in determining plant diversity, production, and species composition [8]. The seasons are a result of the tilt of Earth’s axis that causes variation in environmental conditions and spore density, and community composition of AM fungi are influenced by these changes. To understand the ecology and function of plant-fungus associations in natural ecosystems, it is necessary to clarify seasonal diversity of AM fungi, providing insight into the factors and processes regulating ecosystem development [9]. Studies on the occurrence and diversity of AM fungi from different mangrove plants have been documented [2, 10]. However, no studies have been reported on the seasonal dynamics of AM fungi in mangroves. In this paper, spore density and species
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