University of Minnesota, Department of Plant Pathology, St. Paul, MN 55108.
GROWMARK Agronomy Services, Bloomington, IL 61702.
Plant Dis. 2024 Sep;108(9):2672-2676. doi: 10.1094/PDIS-02-24-0367-SC. Epub 2024 Sep 5.
Tar spot of corn ( L.) is a significant disease in the United States and Canada caused by , an obligate biotroph fungus. However, field research critical for understanding and managing the disease has been hindered by a need for methods to inoculate corn with in field environments. In this study, we developed and demonstrated the efficacy of a method to initiate tar spot in field settings using inoculations of corn leaves with inoculum that had been stored at -20°C for 10 months. Stromata of were observed 19 days after inoculations in two field experiments, and stromata resulting from secondary spread were initially observed 39 to 41 days after the initial inoculations. Tar spot was not present in the fields beyond the inoculated areas or localized spread area, signifying that the establishment of initial disease resulted solely from inoculations. This study enhances our understanding of inoculation and infection of corn with and tar spot development in field environments. The results will aid new research into understanding the corn tar spot pathosystem and improving management strategies.
玉米叶斑病（Tar spot of corn）是美国和加拿大的一种重要病害，由专性活体营养真菌 引起。然而，由于需要在田间环境中用 接种玉米的方法，因此对该病害的理解和管理的田间研究受到了阻碍。在这项研究中，我们开发并证明了一种使用在-20°C 下储存 10 个月的 接种物接种玉米叶片以在田间环境中引发叶斑病的方法的有效性。在两项田间试验中，接种后 19 天观察到 的原基，而从二次传播产生的原基最初在初始接种后 39 到 41 天观察到。在接种区域或局部传播区域之外的田间没有出现叶斑病，这表明初始疾病的建立仅来自接种。本研究增进了我们对玉米与 接种和感染以及田间环境中叶斑病发展的理解。研究结果将有助于对玉米叶斑病系统的理解和改进管理策略的新研究。
