Anthracnose (lentils) (Colletotrichum truncatum)

Anthracnose (lentils): biology

The anthracnose pathogen is a mainly stubble-borne disease. The pathogen overwinters and can persist for several years on lentil residue, infecting subsequent crops when tissues touch or conducive weather conditions occur (warm weather, humidity, rain splash and winds).

As a member of the Anthracnose Resistance Task Force, Syngenta worked with Saskatchewan Pulse Growers, Agriculture Canada and other industry stakeholders in 2020 on an anthracnose sampling project that covered an extensive area of Saskatchewan’s lentil growing region.

We found that anthracnose was highly common and infection levels varied greatly in fields that appeared otherwise healthy.

With anthracnose, trouble brews beneath the canopy.

When it comes to anthracnose, the true damage it does to your lentil crop’s yield and quality is often not what’s visible from the road:

• Initial disease symptoms typically develop around the 10 – 12 node stage, or at early flower, on lower leaflets and stems close to the soil surface. At this stage, you may see white to greyish-coloured spots on leaflets and stems. See Figure 1.
• Later – at canopy closure – you’ll begin to see distinct, burnt-looking stem lesions develop like those illustrate in Figure 2. Leaflets will then fall off the plant, and a look under the canopy will show a significant collection of these leaflets.
• The stem lesions eventually girdle the stem and cause death, which can result in extensive yield losses. You may also see small to large dead patches developing in the crop as shown in Figure 3.