![]() Fully-grown caterpillars are 4 to 5 cm long. Older caterpillars have a plump body their colour varies from grey, dark green to brown or black with shiny, greasy-looking skin. Young caterpillars are pale, yellowish-green with a blackish head. Damp, low-lying areas within untilled fields are particularly attractive for egg-laying moths. Preferred substrates are densely growing plants relatively low to the ground and fine-textured plant debris in untilled fields. Eggs are laid singly or in small groups on moist soil, on weeds or on the stem and lower leaves of host plants or on low growing vegetation. When newly laid they are cream coloured turning reddish-yellow to blackish before hatching. ![]() The eggs are ribbed, globular and small (about 0.5 mm in diameter). ![]() Roots: Holes ranging from small and superficial to very large deep ones. Leaves: "windowpane" holes on leaves abnormal leaf fall. Seedling stage and vegetative growing stage. potatoes) may be difficult to recognise before harvest.ĭamage is far more severe under very dry conditions and occurs deeper below the surface ( Thygesen, 1971 Esbjerg, 1990). Whole plants fall over and on root crops deep holes become visible at and above the soil surface. The activity of the fully-grown caterpillars is very obvious. A further sign of their activity is the presence of leaf pieces partly pulled down into the soil. Alternatively, small holes may be found on the stems and roots at the soil surface. Feeding on tubers and roots results in a variety of holes, ranging from small and superficial to very large deep ones.įeeding by medium to large caterpillars is easier to recognise because whole leaves may fall off the plant after being cut through at the base of the stalk. Feeding on leaves, stalks and stems results in falling leaves, small holes in the stems or cut stems respectively. Common host plants include okra, cabbage, cauliflower, rutabaga, bell pepper, tomato, potato, maize and cotton.Įxternal feeding on leaves by young caterpillars results in the presence of very tiny round 'window panes'. Close-up of cutworm (inset)Ĭutworms attack cultivated plants belonging to more than 15 families. Okra seedling damaged by cutworm caterpillar (right).
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