Data Sheet 1_Pandan–vanilla rotation mitigates Fusarium wilt disease in vanilla: insights from rhizosphere microbial community shifts.pdf

IntroductionVanilla monoculture often leads to Fusarium wilt disease, affecting the industry globally.
MethodsHere, we evaluated the effects of vanilla–black pepper, –pandan, and –sweet rice tea rotations (i.e., growing vanilla in soil previously planted with these crops) on Fusarium oxysporum abundance and rhizosphere microbial communities using real-time quantitative PCR and high-throughput sequencing.
ResultsPandan rotation, in particular, reduced disease incidence to 17% and decreased F. oxysporum copy numbers; sweet rice tea showed similar suppressive effects. Crop rotation significantly increased fungal diversity and richness. Different cropping systems, including fallow, monoculture and crop rotation, significantly influenced fungal and bacterial community development, with cropping system and rotated crops being the main drivers of rhizosphere community assembly. The black pepper and pandan rotations specifically enriched certain fungal OTUs, such as OTU1_Thermomyces, OTU37_Arthrobotrys, and OTU18_Arthrobotrys, which serve as biomarkers for the presence of F. oxysporum. After pandan rotation, microbial interactions within the rhizosphere intensified, with notable enrichment of core bacterial taxa, including OTU22_Nitrosospira, OTU56_Lacibacterium, and OTU178_Actinospica. Soil pH was identified as a significant factor influencing microbial community assembly. The fungal community structure, along with core OTU22_Nitrosospira and soil pH, was pivotal in curbing pathogen growth, explaining 25.19%, 8.61%, and 20.45% of the variance, respectively.
ConclusionThis study revealed that incorporating pandan into crop rotation may effectively alleviate soil-borne diseases during vanilla production.

引言：香草单作常引发镰刀菌枯萎病（Fusarium wilt），对全球香草产业造成负面影响。
方法：本研究针对香草-黑胡椒、香草-香露兜、香草-甜米茶轮作模式（即在前茬种植过上述作物的土壤中种植香草），采用实时荧光定量PCR（real-time quantitative PCR）与高通量测序（high-throughput sequencing）技术，分析轮作对尖孢镰刀菌（Fusarium oxysporum）丰度及根际微生物群落（rhizosphere microbial communities）的影响。
结果：研究结果显示，香露兜轮作可将病害发病率降至17%，并降低尖孢镰刀菌的拷贝数；甜米茶轮作亦表现出类似的抑菌效果。作物轮作可显著提升真菌群落的多样性与丰富度。不同种植体系（包括休耕、单作与轮作）对真菌及细菌群落的构建均产生显著影响，其中种植体系与轮作前茬作物是驱动根际微生物群落组装的核心因素。具体而言，黑胡椒与香露兜轮作可富集特定真菌操作分类单元（Operational Taxonomic Unit，OTU），例如OTU1_热霉属（Thermomyces）、OTU37_节丛孢属（Arthrobotrys）及OTU18_节丛孢属，这些类群可作为尖孢镰刀菌存在的生物标志物。香露兜轮作后，根际微生物间的相互作用增强，核心细菌类群得到显著富集，包括OTU22_亚硝化螺菌属（Nitrosospira）、OTU56_拉西杆菌属（Lacibacterium）及OTU178_放线孢菌属（Actinospica）。土壤pH值被证实为影响微生物群落组装的关键环境因子。真菌群落结构、核心OTU22_亚硝化螺菌属及土壤pH值在抑制病原菌生长过程中发挥关键作用，分别解释了25.19%、8.61%及20.45%的群落变异度。
结论：本研究表明，将香露兜纳入香草轮作体系，可有效缓解香草生产过程中的土传病害。