College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China.
College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China.
Pestic Biochem Physiol. 2024 Sep;204:106028. doi: 10.1016/j.pestbp.2024.106028. Epub 2024 Jul 14.
The destructive disease gray leaf spot, caused by Stemphylium solani, is prevalent in tomato plants in China. A variety of fungicides have been extensively used for controlling the disease, with a particular focus on succinate dehydrogenase inhibitors (SDHIs) and quinone outside inhibitors (QoIs). However, there was a lack of information regarding the resistance of S. solani to boscalid (SDHI) and pyraclostrobin (QoI) in China. In this study, the sensitivity of S. solani to boscalid and pyraclostrobin was monitored. The EC values for boscalid ranged from 0.02 to 3.0 μg∙mL, with an average value of 0.62 μg∙mL, while the EC values for pyraclostrobin ranged from 0.21 to 14.71 μg∙mL, with an average value of 6.03 μg∙mL. Based on these findings, the frequencies of observed resistance were as follows: 36.7% for boscalid and 50% for pyraclostrobin; while the resistance frequency to both boscalid and pyraclostrobin in S. solani was 19.4%. The mutation associated with boscalid resistance in S. solani within tomato fields was identified as SdhB-H277Y, while the mutation related to pyraclostrobin resistance was found in cytochrome b, specifically Cytb-G143A. The resistant mutants displayed diminished fitness in terms of mycelial growth, yet their pathogenicity exhibited no significant disparities. To delay the development of resistance, it is advisable to employ a rotation strategy using alternative fungicides with different modes of action or mix with fungicides with multi-site-contact activity for disease management.
由叶点霉引起的破坏性病害灰斑病在中国番茄植株中普遍发生。为了控制这种病害，人们广泛使用了多种杀菌剂，其中特别关注琥珀酸脱氢酶抑制剂（SDHIs）和醌外抑制剂（QoIs）。然而，关于中国叶点霉对啶酰菌胺（SDHI）和吡唑醚菌酯（QoI）的抗性情况，我们知之甚少。在本研究中，我们监测了叶点霉对啶酰菌胺和吡唑醚菌酯的敏感性。啶酰菌胺的 EC 值范围为 0.02 至 3.0μg∙mL，平均值为 0.62μg∙mL，而吡唑醚菌酯的 EC 值范围为 0.21 至 14.71μg∙mL，平均值为 6.03μg∙mL。基于这些发现，观察到的抗性频率如下：啶酰菌胺为 36.7%，吡唑醚菌酯为 50%；而叶点霉对啶酰菌胺和吡唑醚菌酯的双重抗性频率为 19.4%。在番茄田叶点霉中与啶酰菌胺抗性相关的突变被鉴定为 SdhB-H277Y，而与吡唑醚菌酯抗性相关的突变发生在细胞色素 b 中，具体为 Cytb-G143A。抗性突变体在菌丝生长方面表现出较低的适应性，但它们的致病性没有明显差异。为了延缓抗性的发展，建议采用轮换策略，使用具有不同作用模式的替代杀菌剂，或与具有多部位接触活性的杀菌剂混合使用，以进行病害管理。
