Marek-Kozaczuk Monika, Wdowiak-Wróbel Sylwia, Kalita Michał, Chernetskyy Mykhaylo, Deryło Kamil, Tchórzewski Marek, Skorupska Anna
Department of Genetics and Microbiology, Maria Curie-Skłodowska University, Akademicka 19, 20-033, Lublin, Poland.
The Botanic Garden of Maria Curie-Skłodowska University, Sławinkowska 3, 20-810, Lublin, Poland.
Antonie Van Leeuwenhoek. 2017 Dec;110(12):1729-1744. doi: 10.1007/s10482-017-0922-7. Epub 2017 Aug 8.
Trifolium rubens L., commonly known as the red feather clover, is capable of symbiotic interactions with rhizobia. Up to now, no specific symbionts of T. rubens and their symbiotic compatibility with Trifolium spp. have been described. We characterized the genomic diversity of T. rubens symbionts by analyses of plasmid profiles and BOX-PCR. The phylogeny of T. rubens isolates was inferred based on the nucleotide sequences of 16S rRNA and two core genes (atpD, recA). The nodC phylogeny allowed classification of rhizobia nodulating T. rubens as Rhizobium leguminosarum symbiovar trifolii (Rlt). The symbiotic efficiency of the Rlt isolates was determined on four clover species: T. rubens, T. pratense, T. repens and T. resupinatum. We determined that Rlt strains formed mostly inefficient symbiosis with their native host plant T. rubens and weakly effective (sub-optimal) symbiosis with T. repens and T. pratense. The same Rlt strains were fully compatible in the symbiosis with T. resupinatum. T. rubens did not exhibit strict selectivity in regard to the symbionts and rhizobia closely related to Rhizobium grahamii, Rhizobium galegae and Agrobacterium radiobacter, which did not nodulate Trifolium spp., were found amongst T. rubens nodule isolates.
红车轴草（Trifolium rubens L.），通常被称为红羽三叶草，能够与根瘤菌进行共生相互作用。到目前为止，尚未描述红车轴草的特定共生体及其与三叶草属植物的共生兼容性。我们通过分析质粒图谱和BOX-PCR对红车轴草共生体的基因组多样性进行了表征。基于16S rRNA和两个核心基因（atpD、recA）的核苷酸序列推断了红车轴草分离株的系统发育。nodC系统发育允许将结瘤红车轴草的根瘤菌分类为豌豆根瘤菌共生变种三叶草（Rlt）。在四种三叶草物种上测定了Rlt分离株的共生效率：红车轴草、紫花苜蓿、白车轴草和平卧三叶草。我们确定，Rlt菌株与其原生寄主植物红车轴草大多形成低效共生，与白车轴草和紫花苜蓿形成弱效（次优）共生。相同的Rlt菌株与平卧三叶草共生时完全兼容。红车轴草对共生体没有严格的选择性，在红车轴草根瘤分离物中发现了与格雷厄姆根瘤菌、加莱根瘤菌和放射形土壤杆菌密切相关的根瘤菌，这些根瘤菌不能使三叶草属植物结瘤。
