The Effect of the Injury Caused by Tea Leaf Roller, Caloptilia theivora on the Quality and Yield of Tea

Abstract

This paper reports the influence of damage by tea leaf roller, Caloptilia theivora WALSINGHAM on the qualities and yield of tea.This pest gives a serious damage to the tea plant as rolling the young leaves.Contamination of this rolled leaves deteriorates the qualities of manufactured tea, especially causes taint to the color of liquor. But when the contamination of rolled leaves is less than 3 per cent, contaminating influence is not recognized on the qualities of tea, and the infested leaves by the leaf mining larvae are permissible.The injuries of leaves by the first, second and third instar, and the leaf mining stage do not influence the growth and yield of the tea plant.The decrease of production is caused by the fourth and fifth instar in the leaf rolling stage.From these results, it is pointed out that the control of this pest has to be carried out in the leaf mining stage.