CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department of Microbial and Molecular Systems, KU Leuven, Willem De Croylaan 46, B-3001 Leuven, Belgium.
Leuven Plant Institute (LPI), KU Leuven, B-3001 Leuven, Belgium.
FEMS Microbiol Ecol. 2021 Dec 17;97(12). doi: 10.1093/femsec/fiab153.
The rhizosphere is a complex ecosystem consisting of microbes in the interface between growth medium and plant roots, which affects plant productivity and health. This is one of the few studies analysing bacterial communities present in the rhizosphere of hydroponically grown plants. Tomato grown under hydroponic conditions is prone to hairy root disease (HRD) that is caused by rhizogenic Agrobacterium biovar 1 strains. In this study, using high-throughput amplicon sequencing of partial ribosomal RNA (rRNA) genes, we aimed to characterize bacterial communities in rockwool samples obtained from healthy or HRD-infested tomato during an entire growing season. Alpha diversity of rockwool increased in direct relation with time and samples obtained from healthy greenhouses presented a significantly lower alpha diversity than those from HRD-infested greenhouses. Beta diversity showed that bacterial community composition changed throughout the growing season. Amplicon Sequence Variants (ASVs) identified as rhizogenic Agrobacterium bv. 1 were more prevalent in HRD-infected greenhouses. Conversely, ASVs identified as Paenibacillus, previously identified as biocontrol organisms of rhizogenic agrobacteria, were more prevalent in healthy greenhouses. Altogether, our study greatly contributes to the knowledge of bacterial communities in rockwool hydroponics.
根际是一个复杂的生态系统，由生长介质和植物根系之间界面处的微生物组成，它影响植物的生产力和健康。这是少数分析水培植物根际中存在的细菌群落的研究之一。在水培条件下生长的番茄容易患毛根病（HRD），这是由根瘤农杆菌生物变种 1 菌株引起的。在这项研究中，我们使用高通量扩增子测序部分核糖体 RNA（rRNA）基因，旨在描述整个生长季节中从健康或 HRD 感染的番茄中获得的岩棉样本中的细菌群落。岩棉的α多样性与时间呈直接相关，来自健康温室的样本的α多样性明显低于来自 HRD 感染温室的样本。β多样性表明细菌群落组成在整个生长季节发生了变化。鉴定为根瘤农杆菌 bv. 1 的扩增子序列变异（ASVs）在 HRD 感染温室中更为普遍。相反，先前被鉴定为根瘤农杆菌生物防治剂的 Paenibacillus 的 ASVs 在健康温室中更为普遍。总的来说，我们的研究极大地促进了对岩棉水培中细菌群落的认识。
