Přerovská Tereza, Jindřichová Barbora, Henke Svatopluk, Yvin Jean-Claude, Ferrieres Vincent, Burketová Lenka, Lipovová Petra, Nguema-Ona Eric
Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR-UMR 6226, Univ Rennes, Rennes, France.
Laboratory of Pathological Plant Physiology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague, Czechia.
Front Plant Sci. 2022 May 20;13:893858. doi: 10.3389/fpls.2022.893858. eCollection 2022.
Natural compounds isolated from macroalgae are promising, ecofriendly, and multifunctional bioinoculants, which have been tested and used in agriculture. Ulvans, for instance, one of the major polysaccharides present in spp. cell walls, have been tested for their plant growth-promoting properties as well as their ability to activate plant immune defense, on a large variety of crops. Recently, we have characterized for the first time an arabinogalactan protein-like (AGP-like) from , which exhibits several features associated to land plant AGPs. In land plant, AGPs were shown to play a role in several plant biological functions, including cell morphogenesis, reproduction, and plant-microbe interactions. Thus, isolated AGP-like proteins may be good candidates for either the plant growth-promoting properties or the activation of plant immune defense. Here, we have isolated an AGP-like enriched fraction from and we have evaluated its ability to (i) protect oilseed rape () cotyledons against , and (ii) its ability to activate immune responses. Preventive application of the AGP-like enriched fraction on oilseed rape, followed by cotyledon inoculation with the fungal hemibiotroph , resulted in a major reduction of infection propagation. The noticed reduction correlated with an accumulation of HO in treated cotyledons and with the activation of SA and ET signaling pathways in oilseed rape cotyledons. In parallel, an ulvan was also isolated from . Preventive application of ulvan also enhanced plant resistance against . Surprisingly, reduction of infection severity was only observed at high concentration of ulvan. Here, no such significant changes in gene expression and HO production were observed. Together, this study indicates that AGP-like glycoproteins exhibit promising elicitor activity and that plant eliciting properties of extract, might result not only from an ulvan-originated eliciting activities, but also AGP-like originated.
从大型藻类中分离出的天然化合物是很有前景的、环保且多功能的生物接种剂，已在农业中进行了测试和应用。例如，石莼多糖是石莼属物种细胞壁中的主要多糖之一，已针对其促进植物生长的特性以及激活植物免疫防御的能力，在多种作物上进行了测试。最近，我们首次对石莼中的一种阿拉伯半乳聚糖蛋白样（AGP样）物质进行了表征，它具有一些与陆地植物AGP相关的特征。在陆地植物中，AGP已被证明在多种植物生物学功能中发挥作用，包括细胞形态发生、繁殖以及植物与微生物的相互作用。因此，分离出的AGP样蛋白可能是促进植物生长或激活植物免疫防御的良好候选物质。在此，我们从石莼中分离出了一个富含AGP样物质的组分，并评估了其（i）保护油菜子叶免受核盘菌侵害的能力，以及（ii）激活免疫反应的能力。在油菜上预先施用富含石莼AGP样物质的组分，随后对子叶接种半活体营养型真菌核盘菌，导致感染传播大幅减少。观察到的减少与处理过的子叶中过氧化氢的积累以及油菜子叶中水杨酸和乙烯信号通路的激活相关。同时，还从石莼中分离出了一种石莼多糖。预先施用石莼多糖也增强了植物对核盘菌的抗性。令人惊讶的是，仅在高浓度石莼多糖时才观察到感染严重程度的降低。在此，未观察到基因表达和过氧化氢产生的此类显著变化。总之，这项研究表明石莼AGP样糖蛋白具有有前景的激发子活性，并且石莼提取物的植物激发特性可能不仅源于石莼多糖产生的激发活性，还源于AGP样物质产生的激发活性。
