Kirkman Eleanor R, Hilton Sally, Sethuraman Gomathy, Elias Dafydd M O, Taylor Andrew, Clarkson John, Soh Aik Chin, Bass David, Ooi Gin Teng, McNamara Niall P, Bending Gary D
School of Life Sciences, University of Warwick, Coventry, United Kingdom.
Crops for the Future Research Centre, Semenyih, Malaysia.
Front Microbiol. 2022 Feb 11;13:792928. doi: 10.3389/fmicb.2022.792928. eCollection 2022.
The rhizosphere microbiome is a major determinant of plant health, which can interact with the host directly and indirectly to promote or suppress productivity. Oil palm is one of the world's most important crops, constituting over a third of global vegetable oil production. Currently there is little understanding of the oil palm microbiome and its contribution to plant health and productivity, with existing knowledge based almost entirely on culture dependent studies. We investigated the diversity and composition of the oil palm fungal microbiome in the bulk soil, rhizosphere soil, and roots of 2-, 18-, and 35-year old plantations in Selangor, Malaysia. The fungal community showed substantial variation between the plantations, accounting for 19.7% of community composition, with compartment (root, rhizosphere soil, and bulk soil), and soil properties (pH, C, N, and P) contributing 6.5 and 7.2% of community variation, respectively. Rhizosphere soil and roots supported distinct communities compared to the bulk soil, with significant enrichment of Agaricomycetes, Glomeromycetes, and Lecanoromycetes in roots. Several putative plant pathogens were abundant in roots in all the plantations, including taxa related to and sp. The mycorrhizal status and dependency of oil palm has yet to be established, and using 18S rRNA primers we found considerable between-site variation in Glomeromycotinian community composition, accounting for 31.2% of variation. There was evidence for the selection of Glomeromycotinian communities in oil palm roots in the older plantations but compartment had a weak effect on community composition, accounting for 3.9% of variation, while soil variables accounted for 9% of community variation. While diverse Mucoromycotinian fungi were detected, they showed very low abundance and diversity within roots compared to bulk soil, and were not closely related to taxa which have been linked to fine root endophyte mycorrhizal morphology. Many of the fungal sequences showed low similarity to established genera, indicating the presence of substantial novel diversity with significance for plant health within the oil palm microbiome.
根际微生物群是植物健康的主要决定因素，它可以直接或间接与宿主相互作用，促进或抑制生产力。油棕是世界上最重要的作物之一，占全球植物油产量的三分之一以上。目前，人们对油棕微生物群及其对植物健康和生产力的贡献了解甚少，现有知识几乎完全基于依赖培养的研究。我们调查了马来西亚雪兰莪州2年、18年和35年树龄种植园的块状土壤、根际土壤和根系中油棕真菌微生物群的多样性和组成。真菌群落显示出不同种植园之间存在显著差异，占群落组成的19.7%，其中区室（根、根际土壤和块状土壤）以及土壤性质（pH值、碳、氮和磷）分别贡献了6.5%和7.2%的群落变异。与块状土壤相比，根际土壤和根系支持不同的群落，根部的伞菌纲、球囊菌纲和茶渍纲显著富集。在所有种植园的根部，几种假定的植物病原体数量丰富，包括与 和 属相关的分类群。油棕的菌根状态和依赖性尚未确定，使用18S rRNA引物，我们发现球囊菌群落组成存在显著的位点间变异，占变异的31.2%。有证据表明，在较老的种植园中，油棕根部会选择球囊菌群落，但区室对群落组成的影响较弱，占变异的3.9%，而土壤变量占群落变异的9%。虽然检测到了多种毛霉目真菌，但与块状土壤相比，它们在根系中的丰度和多样性非常低，并且与已与细根内生菌根形态相关的分类群关系不密切。许多真菌序列与已建立的属的相似性较低，表明油棕微生物群中存在大量对植物健康具有重要意义的新多样性。
