THE potato has been grown in Kenya for more than half a century, frequently under conditions of temperature and humidity favourable to blight epidemics. It was not, however, until 1941 that blight appeared, and in that year caused widespread destruction of the crop from the eastern escarpment of the Rift Valley, where the first outbreak was observed, to Mt. Kenya1. In the following year the disease occurred throughout the Highlands, reaching Tanganyika, Uganda and the Belgian Congo, and is now apparently endemic.