Table1_Stalks and roots are the main battlefield for the coevolution between maize and Fusarium verticillioides.xlsx

Fusarium species are the dominant cause of maize ear rot, but they also inflict serious damage to the roots and stalks. Theoretically, the organ where the host interacts with the pathogen most frequently should exhibit the highest degree of symptom-genotype correlation. Because that symptom-genotype correlation is an indicator reflecting the degree of coevolution between pathogen and its hosts. We wonder which organ is the main battlefield for the antagonism between maize and Fusarium. For this purpose, 43 isolates of Fusarium were isolated from infected maize ears. Fusarium verticillioides and F. graminearum are the two dominant pathogens, accounting for 44% and 30%, respectively. Furthermore, 14 elite maize inbreds were exposed to 43 Fusarium isolates and the symptoms of ear rot, stalk rot and root rot were investigated. In general, symptoms caused by F. graminearum were significantly more severe than those caused by other Fusarium species. Surprisingly, the genotype of F. verticillioides showed a strong correlation with stalk and root rot, but not with ear rot. Accordingly, our study may provide the first evidence that the stalk and root of maize, rather than the ear, is the main battlefield for the coevolution between maize and F. verticillioides.镰孢菌属（Fusarium）物种是引发玉米穗腐病的主要病原菌，同时也会对玉米根部与茎秆造成严重危害。理论上，宿主与病原菌互作最频繁的器官，其症状-基因型相关性应最高——该相关性可反映病原菌与宿主间的协同进化程度。本研究旨在明确玉米与镰孢菌属病原菌拮抗互作的主要发生器官。为此，我们从发病玉米果穗中分离得到43株镰孢菌菌株，其中轮枝镰孢菌（Fusarium verticillioides）与禾谷镰孢菌（Fusarium graminearum）为优势病原菌，占比分别为44%与30%。此外，选取14份优良玉米自交系，分别接种上述43株镰孢菌菌株，并对其穗腐病、茎腐病与根腐病的发病症状进行调查。整体而言，禾谷镰孢菌所引发的病害症状显著重于其他镰孢菌物种。值得注意的是，轮枝镰孢菌的基因型与玉米茎腐病及根腐病症状呈现显著相关性，但与穗腐病症状无明显关联。据此，本研究首次提供证据表明，玉米茎秆与根部而非果穗，才是玉米与轮枝镰孢菌协同进化的核心互作场所。