Yssel Johan, Everaerts Vicky, Van Hemelrijk Wendy, Bylemans Dany, Setati Mathabatha Evodia, Lievens Bart, Blancquaert Erna, Crauwels Sam
Department of Microbial and Molecular Systems (M2S), CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), KU Leuven, Leuven, Belgium.
Leuven Plant Institute (LPI), KU Leuven, Leuven, Belgium.
PLoS One. 2025 Sep 2;20(9):e0331039. doi: 10.1371/journal.pone.0331039. eCollection 2025.
Seaweed extracts are promising plant biostimulants for viticulture, but their effects on white winegrape cultivars grown under cool climates remain fairly undocumented. Furthermore, information is limited on the biostimulant potential of some brown seaweed species like Ecklonia maxima. This study evaluated the impact of two commercial extracts (derived from Ascophyllum nodosum and Ecklonia maxima) on Vitis vinifera cv. Chardonnay in Belgium during the 2021 and 2022 growing seasons. The extracts, alongside a water‑control and an NPK‑reference (NPK‑Ref) treatment (with nitrogen, phosphorus, and potassium levels comparable to the extracts), were applied as foliar sprays five times at regular intervals, from flowering to ripening. In 2021 and 2022, A. nodosum significantly increased individual leaf area (+12% and +15%), while in 2021 A. nodosum‑treated vines had an increased chlorophyll content index (+12% CCI) and photosystem II (PSII) reaction centre density (+6%) relative to control vines. This corresponded with a small, but significant, improvement (+1.5%) in PSII maximum quantum yield (Fv∕Fm), whereas PSII electron transport efficiency (ΦE0) remained unchanged. Furthermore, increased berry size, mass, and sugar content were observed in A. nodosum‑treated vines during ripening in 2022, comparable to NPK‑Ref vines. Conversely, the E. maxima extract had limited effects on vegetative growth, physiology, and subsequent berry development. Yield increase from 2021 to 2022 varied by treatment, with a significant increase observed for E. maxima (+60%) and NPK‑Ref vines (+80%), relative to control vines. Our results indicate that seaweed extracts, specifically A. nodosum‑based, can enhance grapevine leaf area, CCI, and Fv∕Fm under cool climatic conditions. A. nodosum treatment was also associated with increased berry size and sugar content, while E. maxima treatment was associated with increased yield in the subsequent, warmer season. Altogether, our study highlights that the differential effects of seaweed extracts on grapevine development are modulated by species and environmental conditions.
海藻提取物有望成为葡萄栽培中颇具前景的植物生物刺激剂，但它们对凉爽气候下种植的白葡萄品种的影响仍鲜为人知。此外，关于一些褐藻物种（如巨藻）的生物刺激潜力的信息也很有限。本研究评估了两种商业提取物（分别源自泡叶藻和巨藻）在2021年和2022年生长季对比利时霞多丽葡萄的影响。这些提取物与水分对照和氮磷钾参考（NPK-Ref）处理（氮、磷和钾水平与提取物相当）一起，从开花期到成熟期每隔一段时间进行五次叶面喷施。在2021年和2022年，泡叶藻显著增加了单叶面积（分别增加12%和15%），而在2021年，与对照葡萄藤相比，经泡叶藻处理的葡萄藤叶绿素含量指数增加（CCI增加12%），光系统II（PSII）反应中心密度增加（增加6%）。这与PSII最大量子产量（Fv∕Fm）有小幅但显著的提高（提高1.5%）相对应，而PSII电子传递效率（ΦE0）保持不变。此外，在2022年成熟期间，经泡叶藻处理的葡萄藤的浆果大小、质量和糖分含量均有所增加，与NPK-Ref葡萄藤相当。相反，巨藻提取物对营养生长、生理和随后的浆果发育影响有限。2021年至2022年的产量增幅因处理方式而异，与对照葡萄藤相比，巨藻处理的葡萄藤（增加60%）和NPK-Ref处理的葡萄藤（增加80%）产量显著增加。我们的结果表明，海藻提取物，特别是基于泡叶藻的提取物，在凉爽气候条件下可以增加葡萄叶面积、CCI和Fv∕Fm。泡叶藻处理还与浆果大小和糖分含量增加有关，而巨藻处理与随后较温暖季节的产量增加有关。总之，我们的研究强调了海藻提取物对葡萄发育的不同影响受物种和环境条件的调节。
