Insights Into the Mondia Whitei Microbiome Across Geographic Regions in Eastern Africa

Mondia whitei (Hook.f.) Skeels is an essential medicinal plant in African societies. However, little is known about the plant's metabolome and its microbiota. Here, we examine the root endosphere and rhizosphere from five locations in Uganda using high-throughput amplicon sequencing, qPCR and multifactorial modelling. Root metabolite profiles obtained with GC/LC-MS were comprehensively catalogued through a deep literature survey using 516 sources. Plant roots were inhabited by microbiota ranging between 50 and 500 ASVs, also with an average microbial abundance of 10¹¹ gene (16SrRNA or ITS) copies per gram. The microbiota was dominated by Gammaproteobacteria, Alphaproteobacteria and Actinobacteria, as well as Sordariomycetes, Dothideomycota, Eurotiomycetes and Agaricomycetes. We identified that a major portion of the microbiome (i.e., 45%-70%) was potentially transferred from the rhizosphere into the roots. Therefore, the root microbiota showed a strong location-specific microbial and metabolite fingerprint. Fraxin, 4-methoxy-benzaldehyde, monobutyl phthalate, 2-hydroxy-4-methoxybenzaldehyde, and scopoletin were among the 86 compounds found in plant roots that were strongly correlated with the root microbiota. Moreover, the identified plant compounds have been shown to mediate microbe, plant, and animal interactions. Our research advances the research frontiers of endangered African herbal plants, through providing insights into the microbiome and potential compounds of M. whitei, a medicinal plant used in sub-Saharan Africa.