Diverging role of phytohormones and soil nutrients between two broad and narrow-distribution orchids of Satyrium species

Abstract

The community assembly of root-associated endophytic fungi not depend on the distribution pattern of host orchids at the local level. In each case, the host plant uses soil nutrients and host compounds to attract endophytic fungi; yet, it is still necessary to investigate how these factors affect the distribution of sample orchids and their associates. Therefore, we assessed the diverging role of phytohormones and soil nutrients in their host distribution. The root-associated fungi were investigated using the amplicon sequencing method and evaluated the host chemical profiles/soil nutrients associated with the roots of sample species using Gas Chromatography-Mass Spectrometry and High Performance-Liquid Chromatography. Finally, we used the correlation analysis method to examine their relationship with endophytic fungi. Using soil samples that were taken, we assessed nine soil nutrients along with soil pH. Likewise, 22 phytohormones were found in the roots of sample orchids. Where, both sample orchids (Satyrium nepalense D. Don. and Satyrium yunnanense Rolfe.) were dominated by distinct endophytic fungal families (Unclassified_k_fungi and Hygrophoraceae) independently, and they showed either positive or negative correlation with phytohormones and soil nutrients based on the distribution pattern of host orchids. The narrowly-distributed orchid was rich by soil nutrients and endophytic fungi but the broadly-distributed orchid was rich by phytohormones and poor in fungi composition in local level So, the diversity and community composition of endophytic fungi was not related to phytohormones but positively related with soil nutrients in local level. Our limited data cannot provide strong evidence but this finding may open the door for further study over the distribution of orchids and their symbionts. Finally, our results help in ecological resilience and potential biotechnological application or conservation of orchids and their symbionts.