Hakalová Eliška, Čechová Jana, Tekielska Dorota A, Eichmeier Ales, Pothier Joël F
Mendeleum - Institute of Genetics, Mendel University in Brno, Brno, Czechia.
Environmental Genomics and Systems Biology Research Group, Institute of Natural Resource Sciences, Zurich University of Applied Sciences (ZHAW), Wädenswil, Switzerland.
Front Microbiol. 2022 Oct 28;13:1007988. doi: 10.3389/fmicb.2022.1007988. eCollection 2022.
The seed-borne bacterium pv. (Xcc) as a causal organism of black rot disease remains the most serious bacterial problem of agricultural production of cruciferous plants worldwide. The eradication of a primary inoculum originating in seeds is available, but no treatment is totally effective. With the threat of developing chemical resistance and increasing pressure for sustainable disease management, biocontrol methods represent one of the main strategies currently applied in agriculture. Natural antimicrobials, including essential oils, are promising tools in disease management with low risks of environmental pollution and impact on human health. Thyme and clove essential oils were demonstrated to be highly effective in studies ; therefore, their application in black rot control was evaluated in this study. From five phenolic substances originating from thyme and clove essential oils (carvacrol, eugenol, linalool, -cymene and thymol), the most promising results were observed with carvacrol, for which 0.0195% led to the death of all Xcc cells in 30 min. Moreover, a synergistic antibacterial effect of carvacrol and thymol solutions decreased the minimal inhibition concentration to 0.0049% and 0.0195% for carvacrol and thymol, respectively. Using the quadruple bactericidal values, the complete elimination of Xcc from the surface of infested cabbage seeds was obtained for both carvacrol and thymol solutions and their combined mixture at 2 MIC value. The elimination of bacterial infection from germinated cabbage plants was observed for both plate counting and quantitative real-time PCR methods. We also evaluated the effect of the application of phenolic treatment on the seed germination and germinated plants. Our results suggest a high potential of the application of carvacrol and thymol in vegetable seed production, specifically for cabbage, thus representing a suitable alternative to cupric derivatives.
种子携带的野油菜黄单胞菌（Xcc）作为黑腐病的病原生物，仍然是全球十字花科植物农业生产中最严重的细菌问题。虽然可以消除种子中的初始接种体，但没有一种处理方法是完全有效的。随着产生化学抗性的威胁以及可持续病害管理压力的增加，生物防治方法是目前农业中应用的主要策略之一。包括香精油在内的天然抗菌剂是病害管理中有前景的工具，对环境污染和人类健康影响的风险较低。百里香和丁香精油在研究中已证明具有高效性；因此，本研究评估了它们在防治黑腐病中的应用。在源自百里香和丁香精油的五种酚类物质（香芹酚、丁香酚、芳樟醇、对异丙基甲苯和百里香酚）中，香芹酚的效果最有前景，0.0195%的香芹酚在30分钟内可导致所有Xcc细胞死亡。此外，香芹酚和百里香酚溶液的协同抗菌作用分别将香芹酚和百里香酚的最小抑菌浓度降至0.0049%和0.0195%。使用四倍杀菌值，对于香芹酚溶液、百里香酚溶液及其混合液，在2倍MIC值时可从受侵染的白菜种子表面完全消除Xcc。通过平板计数和定量实时PCR方法均观察到发芽白菜植株的细菌感染被消除。我们还评估了酚类处理对种子萌发和发芽植株的影响。我们的结果表明，香芹酚和百里香酚在蔬菜种子生产中，特别是白菜种子生产中具有很高的应用潜力，因此是铜衍生物的合适替代品。
