Aqueous extracts from Anabaena minutissima BEA 0300B (ANA), Ecklonia maxima (ECK) and Jania adhaerens (JAN) were evaluated for their antifungal effect against powdery mildew disease caused by Podosphaera xanthii on cucumber detached cotyledons and seedlings. All the extracts were sprayed on detached cotyledons at 2.5, 5.0 and 10.0 mg dry biomass mL⁻¹ water and those of ANA and JAN at 5.0 and 10.0 mg mL⁻¹ on seedlings before pathogen challenge (10⁶ spores mL⁻¹). ANA and JAN at 5.0 and 10.0 mg mL⁻¹ reduced infected area and fungal sporulation on both detached cotyledons and seedlings. ANA and JAN at 5.0 and 10.0 mg mL⁻¹ were also evaluated for their elicitation of seedling defence responses, 1, 2 and 3 days before P. xanthii inoculation. Treatments reduced disease symptoms depending on extract, concentration and application time. Both extracts differentially induced the expression of PR genes, which may have concurred to pathogen control. At all times, ANA mainly induced AePR3 and PR1 genes, at 5.0 and 10.0 mg mL⁻¹, respectively, while JAN mainly induced AePR3 and PR4 at 5.0 mg mL⁻¹. This suggests that both ANA and JAN activated the expression of genes within the jasmonic acid and salicylic acid pathway. Proteins, phycobiliproteins, chlorophylls, carotenoids and antioxidant activities determined in the extracts could be involved in the antifungal effect or induction of plant systemic resistance. These results demonstrate that aqueous extracts from algae and cyanobacteria may be considered for further studies as a bio-based strategy for sustainable disease management.

从含水提取鱼腥minutissima BEA 0300B（ANA），Ecklonia最大值（ECK）和Jania adhaerens（JAN），用于其针对由白粉病疾病抗真菌效果进行了评价叉丝单囊苍耳对黄瓜子叶分离和幼苗。所有的提取物在2.5，5.0和10.0毫克干生物质毫升喷雾在子叶分离^-1水和那些ANA和JAN的在5.0和10.0mg毫升^-1上病原体攻击前秧苗（10个⁶孢子毫升^-1）。ANA和JAN分别为5.0和10.0 mg mL ^-1减少了分离的子叶和幼苗的感染面积和真菌孢子形成。在黄腐病菌接种前1、2和3天，还评估了ANA和JAN分别为5.0和10.0 mg mL ^-1引起的幼苗防御反应。根据提取物，浓度和施用时间的不同，治疗可以减轻疾病症状。两种提取物均差异性诱导PR基因的表达，这可能与病原体控制有关。在任何时候，ANA分别在5.0和10.0 mg mL ^-1下主要诱导AePR3和PR1基因，而JAN在5.0 mg mL ^-1下主要诱导AePR3和PR4基因。。这表明ANA和JAN均激活了茉莉酸和水杨酸途径中基因的表达。提取物中测定的蛋白质，藻胆蛋白，叶绿素，类胡萝卜素和抗氧化活性可能与抗真菌作用或诱导植物的系统抗性有关。这些结果表明，藻类和蓝细菌的水提物可能被认为是基于生物的可持续疾病管理策略，需要作进一步研究。