Abstract
Since 1922, more than 2300 varieties of cultivated rice were widely colleected in the rice growing countries in the world. They were grown on the field of the Experimental Farm of the Kyushu Imperial University under the managements of the Plant Breeding Institute. Although many of the tropical or subtropical varieties were unable to produce seeds on account of the unfavorable climatoligical conditions, pedigree cultures of more than 1000 varieties have been carried on every year. During the three successive seasons from 1938 to 1940, observations were made with 1089 varieties on the distribution of pigments in the plant, and the results obtained are presented in this paper.
The varieties were classified into four main types by the colour tone, that is colourless or green type, red coloured type, purple coloured type and the other miscellaneous coloured type. The number of varieties belonging to each type respectively amounted to 749, 160, 146, and 43.
Three coloured types excepting the first were then subdivided into classes according to the coloured parts or the mode of the distribution of colour. Thus the red type were divided into 17, the purple type into 40 and the last type into 5 classes.
Grouping into nonglutinous, glutinous and mutant varieties, the number of varieties belonging to each classes was summarised for each countries.
The author discussed on the occurence of such special classes as found in particular countries and the common ones of wide distribution from the standpoint of the geographical differentiation of the cultivated rice varieties.
