Abstract：
The use of beneficial microorganisms and polysaccharides for the biocontrol of plant diseases currently represents a promising tool for the management of soil-borne pathogens. Despite advancements, enhancing the efficacy and sustainability of these biocontrol methods, particularly in complex soil environments, remains a challenge. Thus, we investigated the potential of four PGPR strains encapsulated in natural alginate extracted from a brown seaweed Bifurcaria bifurcata to evaluate its biocontrol capacities against Verticillium wilt of tomato, ensuring optimal performance through a synergistic effect and innovative bacterial release. Our research demonstrated that the application of PGPR and alginate reduced disease severity and mortality rate and increased the natural defenses of tomato. Results showed that supplying alginate or the PGPR consortium at the root level s stimulates phenylalanine ammonia-lyase activity (the key enzyme of the phenylpropanoid metabolism) and the accumulation of phenolic compounds and lignin in leaves and roots. Treatment with PGPR encapsulated in alginate beads showed the best biocontrol efficiency and was accompanied by a synergistic effect reflecting a rapid, intense, and systemic induction of defense mechanisms known for their effectiveness in inducing resistance in tomato. These promising results suggest that such bioformulations could lead to innovative agricultural practices for sustainable plant protection against pathogens.
摘要：
目前，将有益微生物和多糖用于植物病害的生物防治是管理土壤传播病原体的有希望的工具。尽管取得了进步，提高这些生物防治方法的有效性和可持续性，特别是在复杂的土壤环境中，仍然是一个挑战。因此，我们调查了四种PGPR菌株的潜力，这些菌株被封装在从褐藻Bifurcariabifurcata中提取的天然藻酸盐中，以评估其对番茄黄萎病的生物防治能力。通过协同效应和创新的细菌释放确保最佳性能。我们的研究表明，PGPR和藻酸盐的应用降低了疾病的严重程度和死亡率，并增加了番茄的自然防御能力。结果表明，在根水平提供海藻酸盐或PGPR聚生体刺激苯丙氨酸解氨酶活性（苯丙素代谢的关键酶）以及叶片和根中酚类化合物和木质素的积累。用封装在藻酸盐珠粒中的PGPR处理显示出最佳的生物控制效率，并伴随着协同效应，激烈，和系统诱导防御机制，以其在诱导番茄抗性方面的有效性而闻名。这些有希望的结果表明，这种生物制剂可以导致创新的农业实践，以实现针对病原体的可持续植物保护。
