Sowing rateįollow the recommended sowing rates for your district. Paddock selectionĬhoose a paddock at least 500m from last year's chickpea crop. Treat all seed with a seed dressing registered for ascochyta blight control.
A key strategy is to consider growing varieties with the highest resistance ratings available, however all varieties will require at least one fungicide application at early podding to prevent seed infection. Use seed from a paddock where ascochyta was not detected or was well managed. There are a range of ascochyta disease ratings available in the commercially available varieties.įor further information on disease ratings refer to the Victorian Pulse Disease Guide. Select the variety with the highest level of resistance for ascochyta blight in your district. When growing a new variety, obtain a copy of the variety management package for information on specific disease management. Management requires a combination of farm hygiene, resistant varieties, crop monitoring and the use of fungicides. When selecting varieties the added cost of fungicide applications needs to be considered before selecting and growing susceptible to moderately susceptible varieties. To successfully grow varieties where the ascochyta disease rating is less than moderately resistant, foliar fungicides need to be applied throughout the growing season to avoid serious yield losses. Multiple cycles of infection can occur during the growing season. Symptoms become visible in 4–5 days and pycnidia develop in 7–10 days. During wet weather, the disease can spread further than in dry conditions because spores of the fungus are carried onto neighbouring plants by wind and rain splash.Īscochyta can develop over a wide range of temperatures (5–30☌) but develops fastest when temperatures are between 15 and 25☌ and relative humidity is high. Moisture is essential for infection to occur. Infection can occur at any stage of plant growth, provided conditions are favourable. Spores of the fungus produced on crop residues are carried into new crops by wind. In this stage the fungus survives mainly on infected seed and on crop residues. This fungal disease has an asexual and sexual stage the asexual stage is most common in Australia. When infected seeds are sown, the emerging seedlings will develop dark brown lesions at the base of the stem. Severe pod infection usually results in reduced seed set and infected seed. The fungus can penetrate the pod and infect the seed. This creates large blighted patches within crops (Figure 2).Īs the disease progresses elongated lesions can often form on the stem and lead to stem girdling and the stem may die and break off. The disease spreads during cool, wet weather from infected plants to surrounding plants by rain splash of spores. In severe cases of infection the entire plant dries up suddenly and small patches of brown, dead plants appear throughout the paddock. Small black spots (pycnidia), less than 1mm in diameter, can be seen in the affected areas (Figure 1). These spots rapidly enlarge under cool and wet conditions, joining with other spots on the leaves and blighting the leaves and buds. This disease is usually first noticed in late winter when small patches of blighted plants appear throughout the paddock. Variety selection, along with an understanding of the associated disease management package for the variety being grown, is critical for success. Temperate pulse viruses: subterranean clover stunt virusĪscochyta blight of chickpea is caused by the fungal pathogen Ascochyta rabiei (formerly known as Phoma rabiei).
Temperate pulse viruses: pea seed-borne mosaic virus
Temperate pulse viruses: bean yellow mosaic virus Temperate pulse viruses: bean leafroll virus Temperate pulse viruses: cucumber mosaic virus
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