This study aimed to evaluate the protective effects conferred by polysaccharides obtained from basidiocarps discarded from the commercial production of Lentinula edodes (shiitake mushroom) in tomato cultivars against bacterial spot disease and to study their mode of action. Among 13 cultivars analyzed for resistance to Xanthomonas gardneri cvs. Kada, Natália and Sena were selected and sprayed with polysaccharides from shiitake (PSHII – 1.5 mg/mL) or distilled water 4 days before inoculation with the bacteria. PSHII promoted a 37.7% reduction in disease severity and its mode of action on plants was evaluated according to changes in photosynthetic parameters, and histopathological aspects. Leaves of plants treated with PSHII showed lower stomatal conductance and transpiration rate compared to the control, at the time of inoculation. In addition, in plants of the most susceptible cvs. (Kada and Natalia) treated with PSHII, phenols accumulated in cells close to the epidermis. We observed that the plants of the most resistant cultivar, Sena, presented higher stomatal density, mesophyll thickness and size of palisade cells. In Sena, we also observed intense cell proliferation near the X. gardneri infection site and deposition of phenolic compounds inside the mesophyll. Control of bacterial spot in different tomato cultivars through induced resistance and the mechanisms presented by the plants to resist the bacteriosis are discussed.

这项研究旨在评估从商业生产的香菇（香菇）中丢弃的沉香的多糖获得的番茄品种对细菌斑病的保护作用，并研究其作用方式。在分析了对黄单胞菌抗性的13个品种中简历 选择Kada，Natália和Sena，并在接种细菌前4天用香菇多糖（PSHII – 1.5 mg / mL）或蒸馏水喷洒。PSHII促进了疾病严重程度降低了37.7％，并且根据光合作用参数的变化和组织病理学方面评估了其对植物的作用方式。在接种时，与对照相比，用PSHII处理的植物的叶片显示出较低的气孔导度和蒸腾速率。此外，在最易受感染的简历中。（Kada和Natalia）用PSHII处理后，酚在表皮附近的细胞中积累。我们观察到，抗性最强的品种塞纳的植物呈现较高的气孔密度，叶肉厚度和栅栏细胞大小。在塞纳（Sena），我们还观察到了附近的强烈细胞增殖X. gardneri感染部位和叶肉内部酚类化合物的沉积。讨论了通过诱导抗性来控制不同番茄品种中的细菌斑点，以及植物所呈现的抵抗细菌病的机制。