Ascochyta is one of the world’s major chickpea diseases, and is currently a major problem in the South Australian and Victorian chickpea growing areas, but also is present in Western Australia and New South Wales. In areas where this disease is endemic, losses average are approximately at 50 per cent; individual crop losses may be greater.
Symptoms of the disease usually are first noted in late winter when small patches of blighted plants become visible throughout paddocks. Ascochyta speads to healthy parts of the crops during cool wet weather from infected plants by rain splash of spores (Dept Ag Vic).
Ascochyta can survive in the soil, on infected seed and on crop residues. Infection can occur at any stage of plant growth, depending upon environmental conditions. Moisture is essential for the disease to infect. Ascochyta is spread by both wind and rain-splash. Initially it appears on the younger leaves as small water-soaked spots. These rapidly elongate and become lesions on the leaves and buds. Small black spots can be seen in the affected area. Lesions around the stem cause the plant to collapse. In severe cases, the plant dries up suddenly.
- Treat the seed with a seed treatment such as Thiraflo or Evershield
- Sow disease free seed and practice good farm hygiene
- Increase the length of rotation between chickpea crops and monitor crops
- Use of resistant varieties