The fungus causes a rot of the crown of the plant with similar results to that of the root rots and wilts mentioned above. In contrast to those problems, this is a hot weather disease and is worst in dry soil. Control the disease by maintaining adequate water in the root zone through regular irrigation. Root knot nematodes are common in most soils and can cause wilting and illthrift in hot weather. Use of infected runners can spread the disease but in the main the problem is soil borne.
Roots become galled or knotted and uptake of water and nutrients is affected.
Preplanting treatment with soil fumigants or specific nematicides is necessary to control this disease. Eye spot is mainly a leaf disease and if severe will cause sufficient defoliation to affect yield. Symptoms are reddish-purple spots with greyish centres studded with the small black fruiting bodies of the fungus. When severe, the leaves scorch and may fall. Spread is most rapid in wet weather, the fungus being spread in rain splash.