Effect of varying population and feeding preferences of Helopeltis schuotedeni Reuter (Hemiptera: Meridae) on parts of tea shoot (Camellia sinensis Kuntze) in Kenya

Abstract

Tea (Camellia sinensis Kuntze) is a very important cash crop in Kenya. Several insect pests, however, have been recorded on tea affecting production and prominent among which is the tea mosquito, Helopeltis schoutedeni Reuter. The tea mosquito bug is assumed to damage the pluck able shoots and can cause up to 60% crop loss by denying the farmer any plucking shoots. This study was conducted to determine the effect of varying population on puncture numbers and the most preferred part of the tea shoot by the tea mosquito bug (Helopeltis schuotedeni Reuter) in a greenhouse at Tea Research Foundation of Kenya. Five population levels of pests were used as treatments and replicated three times in a completely random design. Data on the punctures were collected on different parts of the leaves. The result showed that punctures made by the insects increased significantly (p=0.01) with the increase in the insect population. Punctures made by one to three tea mosquito bugs were significantly less than punctures made by four and five pests on shoots. There was also a significantly (p<0.01) lower number of punctures on internodes made by three pests than those made by five pests but there was no significant difference of punctures on different internodes. There were significant (p<0.01) effect to puncture distribution on the shoot. Feeding preference was concentrated on first and second leaves of the shoot than the other parts. This study showed that the bug prefers the pluckable parts of the bush and that the threshold population that would cause significant damage to tea shoot are three bugs and above.

Key words: Helopeltis schoudoteni, tea mosquito bug, feeding preference, threshold population, Kenya.