Department of Crop and Soil Sciences, Washington State University, PO Box 646420, Pullman, WA 99164, USA.
USDA-ARS: Wheat Health, Genetics and Quality Research Unit, Pullman, WA 99164-6430, USA.
Plant Physiol Biochem. 2018 Aug;129:429-436. doi: 10.1016/j.plaphy.2018.06.011. Epub 2018 Jun 13.
Leaf chlorosis in vineyards is associated with reduced crop yields and quality. While iron (Fe) is understood to play a crucial role in chlorosis, total plant and soil Fe are not always indicative of chlorosis in grapevines. Physiology of chlorosis in vineyards has been well-studied, but the soil microbial consequences of and contributions to chlorosis have received little attention. We used next-generation sequencing (NGS) to examine the bacterial and fungal communities associated with grapevines demonstrating varying degrees of visual chlorosis symptoms. Additionally, chemical analyses of soils and grape leaves were used to explore the influence of plant nutritional status and soil chemistry on microbial community composition. Finally, factors influencing bacterial community composition were correlated with predicted bacterial community function. Leaf tissue magnesium (leaf Mg) concentrations and chlorosis rank were correlated with bacterial community composition as determined via dbRDA (distance-based Redundancy Analysis) using Bray-Curtis dissimilarities. Non-metric multidimensional scaling (NMDS) revealed a significant correlation between fungal community composition and soil Fe and pH, along with leaf N, Mg, and Ca (mg.kg). Chlorosis rank was moderately correlated with KEGG Orthology (KO) terms associated with nitrogen (N) and carbon (C) metabolism in soils, while leaf Mg was associated with a spectrum of KO terms including glycosphingolipid biosynthesis, glycan degradation, transporters, and porphyrin and chlorophyll metabolism. Additionally, abundance of many bacterial operational taxonomic units was significantly correlated with leaf Mg, including those from the following orders: Rhodobacterales, Acidobacteriales, Opitutales, Sphingomonadales, Burkholderiales, Saprospirales, and Flavobacteriales. Our findings suggest grapevine chlorosis is interrelated with soil microbial community structure and function, plant nutrition, and soil chemistry.
葡萄园叶片黄化与作物产量和品质下降有关。尽管人们知道铁（Fe）在黄化中起着关键作用，但植物和土壤中的总铁并不总是能反映出葡萄藤的黄化情况。葡萄园黄化的生理学已经得到了很好的研究，但土壤微生物对黄化的影响和贡献却很少受到关注。我们使用下一代测序（NGS）技术研究了表现出不同程度视觉黄化症状的葡萄树相关的细菌和真菌群落。此外，还对土壤和葡萄叶片进行了化学分析，以探讨植物营养状况和土壤化学对微生物群落组成的影响。最后，将影响细菌群落组成的因素与预测的细菌群落功能相关联。叶片组织镁（leaf Mg）浓度和黄化等级与细菌群落组成相关，这是通过基于距离的冗余分析（dbRDA）使用 Bray-Curtis 不相似性确定的。非度量多维尺度分析（NMDS）显示，真菌群落组成与土壤 Fe 和 pH 以及叶片 N、Mg 和 Ca（mg.kg）之间存在显著相关性。黄化等级与土壤中与氮（N）和碳（C）代谢相关的 KO 术语中度相关，而叶片 Mg 与一系列 KO 术语相关，包括糖脂生物合成、聚糖降解、转运蛋白以及卟啉和叶绿素代谢。此外，许多细菌操作分类单元的丰度与叶片 Mg 显著相关，包括红杆菌目、酸杆菌目、卵形菌目、鞘氨醇单胞菌目、伯克霍尔德菌目、螺旋体目和黄杆菌目。我们的研究结果表明，葡萄黄化与土壤微生物群落结构和功能、植物营养和土壤化学密切相关。
