The response of arbuscular mycorrhizal fungi to nitrogen and phosphorus addition along with subtropical secondary forest succession.. response of Arbuscular mycorrhizal fungi to nitrogen and phosphorus addition

Arbuscular mycorrhizal (AM) fungi form symbiotic relationships with more than 80% of terrestrial plant species and contribute water and nutrient uptake to plants. Thus the responses of AM fungi to fertilization in different plant-growing seasons are very important for understanding biodiversity maintenance, community stability and ecosystem functioning under global climate change scenarios. However, the response of AM fungi Nitrogen and Phosphorus fertilization in subtropical forests across different growth seasons remains largely unexplored. In the present study, we examined the responses of AM fungi to nitrogen and phosphorus fertilization in the subtropical forests of Zhejiang province, China. AM fungal extra-radical hyphal (ERH) density and spore density in soil and colonization rate in root were measured by the morphology based analysis. The AM fungal communities in soil and root were examined using Illumina MiSeq sequencing of 18S rDNA sequences. Drought significantly decreased AM fungal ERH density, spore density and root colonization rate in both seasons. AM fungal ERH density was significantly different between control and phosphorus fertilization treatment. No significant difference in spore density was observed among fertilization treatments but different between two forest successions in nitrogen fertilization treatment. AM fungal abundance and community composition differ significantly in fertilization treatments. But no significant difference was observed in OTU richness. This finding enhances our understanding of the responses of AM fungi to fertilizer addition in subtropical forest ecosystems.