Divergence of rhizosphere microbial communities between females and males of the dioecious Hippophae tibetana at different habitats

Abstract

ABSTRACT Females and males of dioecious plants have evolved sex-specific characteristics in terms of their morphological and physiological properties. However, little is known about the difference in rhizosphere microbes in dioecious plants. In this study, we used amplicon sequencing to analyze the differences in rhizosphere microbial diversity and community composition of males and females of dioecious Hippophae tibetana at different habitats, and their key factors in driving the differences were investigated. The results showed that there were differences in the diversity, community composition, and connectivity and complexity of the co-occurrence network of rhizosphere microbes between females and males of the dioecious H. tibetana at different habitats. Zoopagomycota is a unique phylum of rhizosphere fungi in the males of the dioecious H. tibetana , while Dependentiae is a unique phylum of rhizosphere bacteria in the females of the dioecious H. tibetana . Linear discriminant analysis effect size (LEfSe) analysis indicated significant enrichment of species at different levels, suggesting that these species could be potential biomarkers for females and males of H. tibetana . Spearman’s analysis showed that the dominant genera of rhizosphere fungi were significantly positively correlated with soil physicochemical properties (total nitrogen and phosphorus; organic matter; available phosphorus, potassium and nitrogen; salt content; water content). PICRUSt and FUNGuild predictive analysis indicated that the function of rhizosphere fungi was different between females and males of the dioecious H. tibetana at different habitats, while metabolites were the dominant functions of rhizosphere bacteria in all samples. These results highlighted the sexual discrimination of rhizosphere microbes on the dioecious plants and provided important knowledge for females and males of the dioecious plant–microbe interaction. IMPORTANCE This study explores the differences in rhizosphere microbes of dioecious Hippophae tibetana at different habitats and their key factors in driving the differences. Through employing amplicon sequencing techniques, we found that rhizosphere microbial communities and diversity were different between females and males of the dioecious H. tibetana at different habitats, and there notably existed unique phylum and potential biomarkers of rhizosphere microbes between females and males of the dioecious H. tibetana . Rhizosphere fungi were significantly positively correlated with soil physicochemical properties. This study reveals the differences in rhizosphere microbes of dioecious H. tibetana at different habitats and driving factors; it also contributes to our understanding of the dioecious plant–microbe interaction.