MA Zhoujie, ZHANG Nan, REN Jiankai, WEN Shenghui, YANG Junwei, WANG Jianjun, ZHAO Bianping
To investigate the species composition and pathogenicity of Fusarium pathogens causing maize ear rot in Shanxi Province, a total of 1 238 diseased ear samples were collected from 51 cities/counties/districts across four geographical regions (Northern, Central, Southern, and Southeastern Shanxi) during 2022-2024. From these samples, 1 430 single-spore isolates were obtained. The pathogens were identified using a combination of morphological and molecular biological methods. The results showed that Fusarium was the dominant genus, comprising 1 229 isolates and accounting for 85.94% of the total isolates. Eleven Fusarium species were identified, including F. verticillioides, F. proliferatum, F. subglutinans, F. graminearum, F. boothii, F. oxysporum, F. incarnatum, F. equiseti, F. poae, F. sporotrichioides, and F. acuminatum, with isolation frequencies of 52.73%, 20.34%, 8.62%, 6.02%, 5.53%, 4.39%, 1.06%, 0.98%, 0.16%, 0.08%, and 0.08%, respectively. The composition and isolation frequency of Fusarium species varied by region and year. F. verticillioides was the most widely distributed species across all regions in Shanxi Province and maintained the highest isolation frequency throughout the study period. Pathogenicity tests demonstrated that F. graminearum was the most virulent, with an average disease rating and disease index of 7.39 and 82.07, respectively. In contrast, F. verticillioides and F. subglutinans exhibited comparatively weaker virulence, with average disease ratings of 2.55 and 1.93, and disease indices of 28.30 and 21.38, respectively. These findings offer a theoretical basis for breeding resistant varieties and developing integrated control strategies for maize ear rot in Shanxi Province.
