In Alberta and Manitoba, Aphanomyces euteiches has been identified for quite some time, but this pathogen was first reported in Saskatchewan in 2012. Aphanomyces root rot affects pea, lentil, bean, vetch, clover and alfalfa. Chickpea, canola, flax, soybean, cereal crops and some cultivars of faba bean are susceptible to other root rots, but have tolerance to Aphanomyces euteiches.
There are no seed treatments registered for the control of Aphanomyces euteiches. Host crops are most severely affected under water-logged conditions; however, it is important to note that crops can be diseased even under ideal moisture conditions. Crops can also suffer due to wet feet regardless of pathogen pressure. A distinguishing feature of Aphanomyces root rot is the development of caramel-coloured roots. When growing under optimal conditions, an infection of Aphanomyces can result in symptoms within 10 days, and spores can be formed between 7 and 14 days. Spores become dormant after being formed, and can survive for more than 10 years in the soil. Diagnostic laboratories can examine freshly infected roots for spores or confirm its presence using DNA testing.
Discovery Seed Labs has developed a molecular assay that detects the presence of Aphanomyces. To screen plants please send the plant and roots with minimal soil in a sealed Ziploc bag. Ensure that we receive the sample 1 – 2 days after extracting the plant from the field. To screen soil for the presence of Aphanomyces please provide approximately 2 cups or 500 ml of soil sampled from the area of soil that is between 4 inches and 9 inches below the surface of the soil.