Potential Plant-To-Plant Transmission: Shared Endophytic Bacterial Community Between Ziziphus lotus and Its Parasite Cuscuta epithymum.

Abstract

Microbiota associated with host-parasite relationships offer an opportunity to explore interactions among plants, parasites, and microbes, thereby contributing to the overall complexity of community structures. The dynamics of ecological interactions between parasitic plants and their hosts in arid environments remain largely understudied, especially in Africa. This study aimed to examine the bacterial communities of Cuscuta epithymum L. (clover dodder), an epiphytic parasitic plant, and its host, Ziziphus lotus L. (jujuba), in an arid environment. Our goal was to uncover the ecological complexities of microbial communities within the framework of plant-plant interactions. We conducted a comprehensive analysis of the bacterial composition and diversity within populations of the C. epithymum parasite, the infected- and non-infected jujuba host, and their interface at the shoots of the host. This involved amplicon sequencing, targeting the V5-V6 regions of the 16S rRNA gene. A total of 5680 amplicon sequence variants (ASVs) were identified, with Pseudomonadota, Bacillota, and Actinobacteriota being prevalent phyla. Among the bacterial communities, three genera were dominant: Cutibacterium, Staphylococcus, and Acinetobacter. Interestingly, analyses of alpha-diversity (p = 0.3 for Shannon index and p = 0.5 for Simplon index) and beta-diversity (PERMANOVA, with p-values of 0.6 and 0.3) revealed no significant differences between Cuscuta-infected and non-infected jujube shrubs, suggesting a shared shoot endophytic bacteriome. This finding advances our comprehension of microbial communities linked to plant-parasite interactions in the arid environments of Africa. Further research on various hosts is required to confirm plant-to-plant bacterial transmission through Cuscuta infection. Additionally, studies on functional diversity, cytology, ecophysiology and the mechanisms by which bacterial communities transferred between host and parasite are necessary.