In nature, plants are typically exposed to various pathogens. A pathogen infestation either strengthens or weakens plant resistance against subsequent pathogen attacks, depending on the different plant-pathogen systems. In this study, it is reported that aphids induce tobacco systemic acquired resistance against the soil-borne bacterium Ralstonia solanacearum. It was found that aphid feeding significantly reduced the disease index and wilt symptoms during R. solanacearum infection, and tobacco resistance positively correlated with aphid density within certain ranges. Analysis of the hormone levels demonstrated that salicylic acid content significantly increased in tobacco leaves and roots, whereas jasmonic acid levels remained unchanged. The expression of defense-related genes was upregulated in both the leaves and roots, and the activities of the defense-related enzymes increased. In addition, microbiological analyses of the rhizosphere revealed that the richness, community structure, and composition of the soil fungi and bacteria changed significantly during aphid infestation. These data indicate that aphid feeding not only induces systemic resistance to R. solanacearum infection but also affects the rhizospheric microbial community, which could result in feedback on plant growth and pathogen control.

在自然界中，植物通常暴露于各种病原体。取决于不同的植物病原体系统，病原体侵染会增强或减弱植物对后续病原体侵袭的抵抗力。在这项研究中，据报道，蚜虫诱导了烟草对土壤传播的青枯雷尔氏菌的系统性抗药性。据发现，蚜虫喂养显著减少在疾病指数和萎蔫症状青枯感染和烟草抗性与蚜虫密度在一定范围内呈正相关。对激素水平的分析表明，烟叶和根中的水杨酸含量显着增加，而茉莉酸水平保持不变。防御相关基因的表达在叶和根中均被上调，并且防御相关酶的活性增加。此外，根际微生物学分析表明，在蚜虫侵染期间，土壤真菌和细菌的丰富度，群落结构和组成发生了显着变化。这些数据表明，蚜虫摄食不仅诱导对青枯菌的系统抗性 感染，但也会影响根际微生物群落，这可能会导致对植物生长和病原体控制的反馈。