A survey of insect pest species associated with sunflower (Helianthus annuus L.) in Kenya.

Abstract

The results are presented of a survey of insect pests on sunflower in Kenya in 1974-75. A list is provided of 80 species of Coleoptera, Hemiptera, Lepidoptera, Orthoptera, Diptera and Thysanoptera that were found damaging the crop in the pre-flowering or post-flowering stage, with an indication of the stage in the life-history of the insect that was injurious, the parts of the plant attacked and the localities affected. The major pests were Agrotis segetum (Schiff.), A. ipsilon (Hfn.), Diachrysia orichalcea (F.) (Plusia orichalcea), Heliothis armigera (Hb.) and Nezara viridula (L.); special attention is paid to the seasonal incidence of these species. The foliage pests Agrotis spp. and D. orichalcea peaked in numbers 2 and 12 weeks, respectively, after crop emergence, and the flowerhead pests H. armigera and N. viridula peaked 18 and 14 weeks after crop emergence; flowering took place at 10 weeks.