International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149, Trieste, Italy.
ARGO Open Lab Platform for Genome sequencing, AREA Science Park, Padriciano 99, 34149, Trieste, Italy.
Microb Ecol. 2020 Oct;80(3):627-642. doi: 10.1007/s00248-020-01529-2. Epub 2020 May 30.
Rice sheath rot has been mainly associated with the bacterial pathogen Pseudomonas fuscovaginae and in some cases to the fungal pathogen Sarocladium oryzae; it is yet unclear if they are part of a complex disease. The bacterial and fungal community associated with rice sheath rot symptomatic and asymptomatic rice plants was determined/studied with the main aim to shed light on the pathogen(s) causing rice sheath rot. Plant samples were collected from different rice varieties in two locations (highland and lowland) in two rice-growing seasons (wet and dry season) in Burundi. Our results showed that the bacterial Pseudomonas genus was prevalent in highland in both rice-growing seasons and was not affected by rice plant varieties. Pseudomonas sequence reads displayed a significant high similarity to Pseudomonas fuscovaginae indicating that it is the causal agent of rice sheath rot as previously reported. The fungal Sarocladium genus was on the other hand prevalent in lowland only in the wet season; the sequence reads were most significantly similar to Sarocladium oryzae. These studies showed that plant microbiome analysis is very useful in determining the microorganisms involved in a plant disease. P. fuscovaginae and S. oryzae were prevalent in symptomatic samples in highland and lowland respectively being present independently and hence are not part of a complex disease. The significant presence of other bacterial and fungal taxa in symptomatic samples is also discussed possibly making this disease more complex. Finally, we also report the microbial communities that are associated with the plant sheath in symptomatic and asymptomatic plants from the same rice fields.
水稻叶鞘腐烂主要与细菌病原体假单胞菌（Pseudomonas fuscovaginae）和在某些情况下与真菌病原体丝核菌（Sarocladium oryzae）有关；目前尚不清楚它们是否属于复杂疾病。本研究旨在阐明引起水稻叶鞘腐烂的病原体，对水稻叶鞘腐烂症状和无症状水稻植株的细菌和真菌群落进行了研究。在布隆迪的两个水稻种植季节（雨季和旱季），从两个地点（高地和低地）的不同水稻品种中采集了植物样本。我们的结果表明，细菌假单胞菌属在两个水稻种植季节的高地上都很普遍，且不受水稻品种的影响。假单胞菌序列读取与假单胞菌（Pseudomonas fuscovaginae）具有显著的高相似性，表明其是先前报道的水稻叶鞘腐烂的病原体。另一方面，丝核菌属真菌仅在雨季的低地流行；序列读取与丝核菌（Sarocladium oryzae）最为相似。这些研究表明，植物微生物组分析在确定参与植物疾病的微生物方面非常有用。P. fuscovaginae 和 S. oryzae 在高地上的症状样本中分别普遍存在，在低地上的症状样本中也普遍存在，它们独立存在，因此不属于复杂疾病。在症状样本中还存在其他细菌和真菌分类群的显著存在，这也可能使该疾病更加复杂。最后，我们还报告了来自同一稻田的症状和无症状植物的叶鞘相关微生物群落。
