Department of Integrative Agriculture, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al-Ain, Abu-Dhabi, UAE.
Department of Biology, College of Science, United Arab Emirates University, Al-Ain, Abu-Dhabi, UAE.
Sci Rep. 2022 Jul 26;12(1):12733. doi: 10.1038/s41598-022-16869-x.
Saline water irrigation has been used in date palm (Phoenix dactylifera L.) agriculture as an alternative to non-saline water due to water scarcity in hyper-arid environments. However, the knowledge pertaining to saline water irrigation impact on the root-associated bacterial communities of arid agroecosystems is scarce. In this study, we investigated the effect of irrigation sources (non-saline freshwater vs saline groundwater) on date palm root-associated bacterial communities using 16S rDNA metabarcoding. The bacterial richness, Shannon diversity and evenness didn't differ significantly between the irrigation sources. Soil electrical conductivity (EC) and irrigation water pH were negatively related to Shannon diversity and evenness respectively, while soil organic matter displayed a positive correlation with Shannon diversity. 40.5% of total Operational Taxonomic Units were unique to non-saline freshwater irrigation, while 26% were unique to saline groundwater irrigation. The multivariate analyses displayed strong structuring of bacterial communities according to irrigation sources, and both soil EC and irrigation water pH were the major factors affecting bacterial communities. The genera Bacillus, Micromonospora and Mycobacterium were dominated while saline water irrigation whereas contrasting pattern was observed for Rhizobium, Streptomyces and Acidibacter. Taken together, we suggest that date-palm roots select specific bacterial taxa under saline groundwater irrigation, which possibly help in alleviating salinity stress and promote growth of the host plant.
由于在极端干旱环境中水资源短缺，海水灌溉已被用于椰枣（Phoenix dactylifera L.）农业，作为非咸水灌溉的替代方法。然而，关于海水灌溉对干旱农业生态系统根相关细菌群落的影响的知识还很缺乏。在这项研究中，我们使用 16S rDNA 代谢组学研究了灌溉水源（非咸淡水与咸地下水）对椰枣根相关细菌群落的影响。灌溉水源之间的细菌丰富度、香农多样性和均匀度没有显著差异。土壤电导率 (EC) 和灌溉水 pH 值分别与香农多样性和均匀度呈负相关，而土壤有机质与香农多样性呈正相关。40.5%的总操作分类单元是淡水灌溉特有的，而 26%的总操作分类单元是咸地下水灌溉特有的。多元分析显示，根据灌溉水源，细菌群落具有强烈的结构，土壤 EC 和灌溉水 pH 值是影响细菌群落的主要因素。在海水灌溉下，芽孢杆菌属、小单孢菌属和分枝杆菌属占主导地位，而根瘤菌属、链霉菌属和嗜酸菌属则呈现相反的模式。总之，我们认为在咸地下水灌溉下，椰枣根选择特定的细菌类群，这可能有助于缓解盐分胁迫并促进宿主植物的生长。
