The prevalence of Fusarium spp. colonizing seed corn stalks in southwestern Ontario, Canada

Gibberella zeae, Fusarium verticillioides and F. subglutinans are the most important causes of Fusarium stalk rot in corn (Zea mays L.). Gibberella zeae also causes fusarium head blight in wheat (Triticum aestivum L.) and gibberella ear rot in corn. The objectives of this study were to investigate prevalence of Fusarium species in the stalks of seed corn over time and to investigate the influence of sampling time and internode position on Fusarium spp. and G. zeae, particularly. Fusarium subglutinans and G. zeae were the most frequently recovered species from asymptomatic host tissue and from pink discoloration on stalks, respectively. More G. zeae was isolated from the basal internode of stalks than from the higher ones closer to harvest time. Other species isolated from seed corn stalks over time included F. verticillioides, F. oxysporum, F. sporotrichioides and F. equiseti. A similar spectrum of Fusarium species was identified from corn ears and from winter wheat across southwestern Ontario. Key words: Zea mays L., Fusarium spp.