Dr. Phyto

oilseed rape / canola

Brassica napus

Diseases & pests on this plant

• pollen beetle / rape blossom beetleBrassicogethes aeneus

  Shiny black 2 mm beetles on developing flower buds and open flowers, buds aborted before opening leave bare flower stalks (candle-stick appearance).

• phoma stem canker / blacklegLeptosphaeria maculans

  Round pale-grey leaf spots with black pycnidia in centre (autumn), grey-brown sunken cankers at stem base in spring, lodging of affected plants in summer.

• Redlegged earth miteHalotydeus destructor

  Silvered, whitened or bleached patches on leaves and cotyledons where mites have fed; distorted, shrivelled seedlings; worst on cool, overcast autumn days on emerging canola, lucerne and pulse crops. Tiny 1 mm black mites with red-orange legs feed in dense groups.

• sclerotinia stem rotSclerotinia sclerotiorum

  White cottony growth on stems at flowering height, stems split open to show black sclerotia (1–5 mm) embedded in pith, premature ripening of affected plants.

• alternaria dark leaf spotAlternaria brassicae

  Dark-brown angular leaf spots with concentric rings (target-pattern), spots later coalesce and leaves drop, dark stem and pod lesions late in season.

• Australian plague locustChortoicetes terminifera

  Marching bands of wingless nymphs and later flying swarms that strip pastures and crop leaves; rapid, patchy defoliation spreading from egg-bed areas; heaviest after warm, wet springs that trigger high densities.