Data from: Consistent alleviation of abiotic stress with silicon addition: a meta-analysis

Hundreds of single species studies have demonstrated the facility of silicon (Si) to alleviate diverse abiotic stresses in plants. Understanding of the mechanisms of Si-mediated stress alleviation is progressing, and several reviews have brought information together. A quantitative assessment of the alleviative capacity of Si, however, which could elucidate plant Si function more broadly, was lacking. We combined the results of 145 experiments, predominantly on agricultural species, in a meta-analysis to statistically assess the responses of stressed plants to Si supply across multiple plant families and abiotic stresses. We interrogated our database to determine whether stressed plants increased in dry mass and net assimilation rate, oxidative stress markers were reduced, antioxidant responses were increased and whether element uptake showed consistent changes when supplied with Si. We demonstrated that across plant families and stress types, Si increases dry weight, assimilation rate and chlorophyll biosynthesis and alleviates oxidative damage in stressed plants. In general, results indicated that plant family (as a proxy for accumulator type) and stress type had significant explanatory power for variation in responses. The consistent reduction in oxidative damage was not mirrored by consistent increases in antioxidant production, indicative of the several different stress alleviation mechanisms in which Si is involved. Silicon addition increased K in shoots, decreased As and Cd in roots and Na and Cd in shoots. Silicon addition did not affect Al, Ca or Mn concentration in shoots and roots of stressed plants. Plants had significantly lower concentrations of Si accumulated in shoots but not in roots when stressed. Meta-analyses showed consistent alleviation by Si of oxidative damage caused by a range of abiotic stresses across diverse species. Our findings indicate that Si is likely to be a useful fertilizer for many crops facing a spectrum of abiotic stresses. Similarities in responses across families provide strong support for a role of Si in the alleviation of abiotic stress in natural systems, where it has barely been explored. We suggest this role may become more important under a changing climate and more experiments using non-agricultural species are now needed.已有数百项单物种研究证实，硅（Si）可缓解植物面临的多种非生物胁迫。目前，关于硅介导的胁迫缓解机制的研究正持续推进，已有多篇综述对相关研究成果进行了系统整合。然而，此前仍缺乏对硅缓解胁迫能力的定量评估——此类评估可更全面地阐明植物对硅的功能作用。 本研究通过元分析（meta-analysis）整合了145项实验的结果，实验对象以农作物为主，以此统计评估受胁迫植物在施加硅肥后，不同植物科属及非生物胁迫类型下的响应特征。我们对自建数据库进行检索分析，以明确施加硅肥后，受胁迫植物的干物质量与净同化速率是否提升、氧化胁迫标志物水平是否降低、抗氧化应答是否增强，以及元素吸收是否呈现一致性变化。 研究结果显示，在不同植物科属与胁迫类型中，硅可提升植物干重、同化速率与叶绿素生物合成能力，并缓解受胁迫植物的氧化损伤。总体而言，结果表明植物科属（作为硅积累类型的替代表征指标）与胁迫类型，均可显著解释植物响应的变异情况。值得注意的是，氧化损伤的持续降低并未伴随抗氧化物质生成的一致性提升，这暗示硅参与了多种不同的胁迫缓解机制。施加硅肥可提升植株地上部分的钾（K）含量，降低根系中的砷（As）与镉（Cd）含量，同时降低地上部分的钠（Na）与镉（Cd）含量。此外，施加硅肥对受胁迫植物根系与地上部分的铝（Al）、钙（Ca）及锰（Mn）浓度无显著影响。当植物遭受胁迫时，其地上部分积累的硅浓度显著降低，但根系硅浓度无此变化。 元分析结果证实，硅可持续缓解多种非生物胁迫在不同物种中引发的氧化损伤。本研究结果表明，对于面临多种非生物胁迫的多数农作物而言，硅有望成为一种实用的肥料。不同植物科属间的响应相似性，为硅在自然生态系统中缓解非生物胁迫的作用提供了强有力的支撑——而这一作用此前几乎未被探索。我们认为，在气候变化背景下，硅的这一作用可能愈发重要，未来亟需开展更多针对非农业物种的相关实验。