Recently, I sat at the edge of my seat, staring at my computer screen in shock as I read a BBC news story about how scientists are battling to save my favourite fruit from extinction. The Panama disease that threatened to wipe out bananas in the 1950s had made an aggressive comeback. This current outbreak was caused by a different strain of the same culprit, Fusarium. The news almost had me going bananas.
What is fusarium?
Although we do not produce bananas here in Western Canada, we are all very familiar with the problems caused by Fusarium. Fusarium is one of the most challenging groups of disease-causing fungi. For example, Fusarium head blight (FHB) is caused by several species of the fungus and affects cereals including wheat, barley, corn, rye, oats and some forage grasses. These fungi overwinter in the soil, on infected crop residue, and on seed. In the spring and summer, they release spores which are spread by rain-splash and wind to cereal heads during flowering. Moist, humid conditions favour infenction when temperatures are between 16 to 28 °C.
Plants can also be infected through wounds caused by insects or birds. Spores that reach a cereal flower may infect the developing kernel. Visible symptoms appear within a few days after infection. Diseased spikelets show premature bleaching as the pathogen spreads within the head (picture below). Over time, the entire head may be affected.
A wheat spikelet showing symptoms of Fusarium head blight infection. Photo: University of Illinois
What does this mean for my crops?
Fusarium head blight causes significant yield losses, and the fungus also produces mycotoxins that downgrade kernel quality and pose a major health threat to domestic animals and humans. An integrated approach is important for controlling its spread and mitigating risks. Some useful strategies include crop rotation, allowing sufficient time for crop residue to decompose, using fusarium-resistant varieties, using a good seed treatment, and applying appropriate fungicides at the start of flowering to suppress FHB. Your SynergyAG rep can guide you in being proactive against Fusarium.
-Ikenna Mbakwe, PhD, PAg
Head of Research