Symptoms:

Both adults and nymphs feed on flower buds and on closed or partially opened cotton bolls. They bore through the fibers and feed on the seeds. The damaged tissues are colonized by microorganisms that cause boll rot and discoloration. Boll abortion, premature opening and early shed are common. Further symptoms are smaller seeds with reduced oil content, stained fibers and lower germination rate. These seeds are not fit for sowing. D. cingulatus is not bound to a single plant and may migrate to other young bolls. A high infestation can cause a severe loss in quality due to the stained lint.

Trigger:

The damage is caused by the nymphs and adults of Dysdercus cingulatus. Adults may reach a length of 12-13 mm and are of a distinct red-orange color. Head is red with a white collar, abdomen is black and forewings have two black dots. Males are smaller than females. Females can lay up to 130 bright yellow eggs at a time in the soil, nearby the host plants. After an incubation period of 7-8 days, nymphs hatch and start to feed on cotton plants. They are also red and have three black dots on the abdomen and three pairs of white dorsal spots. The development period lasts 50-90 days in total, depending on the climate. Infestation occur towards the end of the season, when the first bolls are opening. Alternative hosts include okra, hibiscus and citrus.

Organic Control:

Foliar sprays with diluted neem oil have shown to be effective against this pest.

Chemical Control:

Among the insecticides, Triazophos proved most effective and gave 85% mortality followed by Imidacloprid (79.2%), Profenofos (78.0%) and Dimethoate (75.0%) while Spinosad gave lowest pest mortality (12.5%) followed by Emamectin (16.7%), Pyriproxyfen (25.0%) and Diafenthiuron  (30.0%) after 24 hours of application

Treatment / علاج

Chemical Control:

Among the insecticides, Triazophos proved most effective and gave 85% mortality followed by Imidacloprid (79.2%), Profenofos (78.0%) and Dimethoate (75.0%) while Spinosad gave lowest pest mortality (12.5%) followed by Emamectin (16.7%), Pyriproxyfen (25.0%) and Diafenthiuron  (30.0%) after 24 hours of application