Studies on the pigments of cocoon. VIII On the classification of the silkworm races and its geographical distribution from the viewpoint of the rate of cocoon pigment contents

Abstract

In this investigation, the silkworm (Bombyx mori L.) races have been classified from the viewpoint of the cocoon pigments (carotenoids and flavonoids) contents. As the result, the races (61 colored cocoon races) were divided into the following five groups. A: the greater part (above 80%) of pigments is carotenoids. B: carotenoids are contained more than flavonoids. C: both carotenoids and flavonoids are contained almost equally. D: flavonoids are contained more than carotenoids. E: all of the pigments are flavonoids. The greater part of European races (about 85%) belong to A group and all of the tropical races do to D and E groups. To C group, Theophila mandarina MOOR which is thought to be a progenitor of the silkworm belong, and some of European, Chinese, and Japanese races are among the same group. © 1961, The Japanese Society of Sericultural Science. All rights reserved.