Ascochyta pisi

Pea blight, leaf and pod spot

General

Ascochyta pisi is a fungal plant pathogen that causes Ascochyta blight on pea (leaf blight or pea blight) and lesions of stems, leaves, and pods (pea leaf spot and pea pod spot).

Life cycle and appearance of Pea blight, leaf and pod spot

Ascochyta pisi hardly survives in the soil or on crop residues because of its poor saprophytic competitiveness and because chlamydospores are rare. Primary infection is purely seed-borne. Conidia and other fungal structures are transmitted on the outside of the seed coat and cause primary infection.

The conidia germinate and infect through the stomata or directly through the cuticle. On the lesions, pycnidia are formed from which orange-red masses of two-celled conidia are exuded. Secondary infection is by splash dispersal of these conidia. There is no known sexual stage. Ascochyta fungi develop most rapidly at temperatures below 20 °C and the spores require water for dispersal.

How to prevent Pea blight, leaf and pod spot

  • Grow peas in arid regions
  • Use clean seed
  • Use a minimum crop rotation of four years with non-host crops
  • Bury or remove crop debris

Prevent plant diseases by optimizing plant potential and crop resilience.