Ectomycorrhizal Fungi of Comoé Naitonal Park, a Biosphere Reserve in notheast Côte d’Ivoire: Diversity, Fruiting Phenology and Production in Relation to climate variability

Abstract

The key role of ectomycorrhizal (EcM) fungi in ecosystems functioning has been demonstrated worldwide. However, their diversity, spatial distribution, fruiting phenology and production as influenced by climatic parameters variability remain poorly understood in tropical African forests. Weekly surveys were conducted from April to early October 2014 at the Comoé National Park (CNP), Côte d’Ivoire (West Africa) in nine permanent plots established in Isoberlinia doka (IW), Uapaca togoensis (UW) and Mixed (MW) woodlands. Morpho-molecular technics were used to identify collected specimens and to reconstruct their phylogeny. Non metric multidimensional scaling (NMDS) of EcM fungi fruit bodies abundance was run with forest trees´ aggregation fitted within plots using the package VEGAN. Hierarchical clustering based on dissimilarity and indicator species analysis were run to characterize communities. Final, correlation between edible species production and climatic parameters recorded per plot were performed with functions PRCOMP and COR set at Spearman method. All analyses were computed with the statistical program R. A total of 123 EcM fungi species belonging to 23 genera and nine families collected at CNP. High Simpson index of diversity (1-D) but weak evenness were respectively 0.97 and 0.54 for IW, 0.97 and 0.61 for MW, 0.96 and 0.52 for UW. Yet, weekly-based species accumulation curves did not reach an asymptote. Stem density of Uapaca togoensis Pax and Isoberlinia doka Craib & Stapf were the most important tree parameters in EcM fungi distribution (respectively r2 = 0.92 / p-value = 0.002 and r2 = 0.83 / p-value = 0.018). Two sites groups and four species estimated good indicators were thus highlighted. 27 species were identified as edible based on literature. They started fruiting in mid-May, 02 weeks after the first important rain. Productions varied with frequency and intensity of rainfalls. The total fresh biomass production varied from 34.72 kg/ha in UW to 25.25 kg/ha in MW, whilst IW yielded 24.11 kg/ha. Productions of ten edible species were significantly correlated to all climate parameters recorded per habitat: negatively for air and soil temperature and positively for relative humidity, soil moisture and rainfall intensity. However, production of Gyroporus castaneus was negatively correlated with both soil moisture and rainfall intensity recorded in UW.