Abstract:

The establishment of a coloration method for Fusarium verticillioides can clarify its infection pathway in maize plants and further determine its pathogenic mechanism.This study took Fusarium verticillioides as the research object to explore the staining effects of FDA,trypan blue,toluidine blue,acid fuchsin,basic fuchsin,FM4-64,and red fluorescence vector on fungal spores of F.verticillioides and the root system of maize seedlings inoculated with F.verticillioides.A coloration method for F.verticillioides was established.The results showed that 5% basic fuchsin and 1% toluidine blue had good staining effects on F.verticillioides spores,with clear color and clear structure.After staining with 5.00 g/L FDA,0.4% trypan blue,and 0.50 g/L acid fuchsin,the F.verticillioides spores could be stained with a very light color,making it difficult to observe the spore morphology.Staining the root system of maize seedlings with stains showed that 0.4% trypan blue and 1% toluidine blue stained the root system of maize with blue and brown colors,allowing clear observation of the brown area as the site of root rot caused by F.verticillioides infection in maize.However,staining with 0.50 g/L acid fuchsin and 5% basic fuchsin did not allow clear observation of the site of root rot.Observation of the red fluorescence coloration of F.verticillioides spores showed that FM4-64 had a deeper color and unclear structure,limiting observation time.However,after being transferred to a red fluorescence vector,the fluorescence color was obviousr and the structure was clear,without any time limit for observation.This method can be used in future studies on the pathogenic mechanism of F.verticillioides causing kernel rot in maize and wheat.After comprehensive comparison,the F.verticillioides transferred with a red fluorescence vecror had more advantages than other staining methods in terms of research on pathogenic mechanisms.

Key words: Maize kenel rot, Fusarium verticillioides, Fluorescent vector, Inoculation, Staining