Trifolium repens and T. subterraneum modify their nodule microbiome in response to soil pH

作者：Anish Shah, Steven A. Wakelin, Derrick J. Moot, Céline Blond, Aurélie Laugraud, Hayley J. Ridgway · 发表于：Journal of Applied Microbiology · 年份：2021 · DOI：10.1111/jam.15050 · 被引用次数：11 · 研究领域：Legume Nitrogen Fixing Symbiosis、Soil Carbon and Nitrogen Dynamics、Agronomic Practices and Intercropping Systems

AIMS: The influence of soil edaphic factors on recruitment and composition of bacteria in the legume nodule is unknown. Typically, low (acidic) pH soils have a negative effect on the plant-rhizobia symbiosis and thereby reduce clover growth. However, the specific relationship between soil pH and the ecology of rhizobia is unknown, in either their free-living or nodule-inhabiting states. We used New Zealand pasture systems with soils of different pH, and white (WC) and subterranean (SC) clovers, to examine the relationship between soil pH and the diversity of bacteria that inhabit the nodules. METHODS AND RESULTS: 92% of the total reads in both clovers, however 28 non-rhizobia genera were also present. Soil pH influenced the community structure of bacteria within the nodule, and this was more evident in non-Rhizobium taxa than Rhizobium. Host strongly influenced the diversity of bacteria in the nodules. The alpha diversity of nodule microbiome in SC nodules was higher than in WC nodules and SC nodules also harbored a higher relative abundance of non-Rhizobium bacteria than WC. Beta diversity of Rhizobium and non-Rhizobium bacteria was influenced more by clover species rather than edaphic factors. CONCLUSIONS: The results indicate that these clover species modified their nodule biomes in response to pH-stress. SIGNIFICANCE AND IMPACT OF THE STUDY: The non-Rhizobium bacteria may have some functional significance (such as improved clover persistence in low pH soils) in legume nod...