Plant parasitic nematode (PPN) control has historically relied on the use of synthetic chemical nematicides, however many are toxic to both human health and the environment. The withdrawal of the more harmful nematicides coupled with increases in soil temperatures and increased occurrence of pests and diseases associated with climate change, may enable PPN to increase in numbers and spread globally. The need for sustainable and environmentally friendly management options is necessary while facing future food security scares in order to feed the ever-growing population. Seaweed extracts have been used for decades in agriculture and horticulture as soil biostimulants, however there is a growing body of evidence to suggest that they could be used to reduce the occurrence of damaging PPN infections. Using meta-analysis, we investigated whether seaweed extracts applied to soil could reduce root knot nematode (RKN) abundance and whether there could be confounding factors that influence their efficacy. We found that seaweed extracts reduce RKN performance and that various factors affected the efficacy of seaweed, including the seaweed species itself and the crop the seaweed was applied to. Ascophyllum nodosum extracts were found to be the most effective. Particular RKN species were more sensitive than others to seaweed species used and, in some cases, specific seaweed species only affected particular RKN species. Different life cycle stages were also differentially susceptible to seaweed application, where both egg hatching and population abundance could be reduced via seaweed use. This research indicates that seaweed extracts could potentially be used to help reduce RKN attack on plants.

植物寄生线虫 (PPN) 的控制历来依赖于使用合成化学杀线虫剂，但许多对人类健康和环境都有毒。不再使用更有害的杀线虫剂，再加上土壤温度升高和与气候变化相关的病虫害发生率增加，可能使 PPN 数量增加并在全球范围内传播。在面临未来的粮食安全恐慌以养活不断增长的人口时，需要可持续和环境友好的管理方案。海藻提取物已在农业和园艺中用作土壤生物刺激剂数十年，但越来越多的证据表明它们可用于减少破坏性 PPN 感染的发生。使用荟萃分析，我们调查了应用于土壤的海藻提取物是否会降低根结线虫 (RKN) 的数量，以及是否存在影响其功效的混杂因素。我们发现海藻提取物会降低 RKN 性能，并且各种因素都会影响海藻的功效，包括海藻种类本身和应用海藻的作物。发现泡叶藻提取物是最有效的。特定的 RKN 物种对使用的海藻物种比其他物种更敏感，并且在某些情况下，特定的海藻物种仅影响特定的 RKN 物种。不同的生命周期阶段也对海藻应用的敏感性不同，其中通过海藻使用可以减少卵孵化和种群丰度。这项研究表明，海藻提取物可能有助于减少 RKN 对植物的攻击。