Aphanomyces root rot showing up in pea and lentil fields

Wet spring = increased presence of

Aphanomyces root rot in pea and lentil fields

Mid-June is the time to scout for Aphanomyces root rot as it will start showing up 4 – 6 weeks after seeding when rainfall has been plentiful. Finding it early makes it easy to distinguish from later-season Fusarium species that will overtake Aphanomyces symptoms on the roots.

What to look for:

How to confirm:

Lentil roots with early infection. Lateral roots have a honey-brown colour and a ‘soft rot’. Infection is just starting to move into the epicotyl in some plants (black arrows).

Pea roots with early infection that has already moved into the epicotyl, note pinching of epicotyl that stops at the green stem (blue arrow). The lateral roots are wiry and honey brown. This is evident in the field without having to wash roots.

If roots are washed, the honey-brown discolouration of the lateral roots becomes more obvious, as does the browning of the epicotyl.

What you can do:

Prepared by: Syama Chatterton, June 18, 2024