Abstract
Pedigrea and plant numbers of the artificially indnced napus plants, which have been bred by selfing since 1946 in the progenies of COO (cf. the previous paper I, 1950), are shown in Table 1. The fertility of C-type (chinese cabbage type) plants may be disturbed by the irregular meiosis. That is to say, the fruit setting of 2n=38 plants among them are fairly good and the leaves of the plants are just like those of O-type (forage rape type) or N-type (oil rape type) . On the contrary, the 2n=40, 41 etc. plants have low fertility and their leaves are like those C-type(cf.Table 5). The fertility of O- and N-type plants may be disturbed by an interaction of self, -incompatible genes rather than the irregular meiosis. The O-type plants have already been utilized as a new type of forage rape, but the N-type plant will be worth of consideration as crops when the complete self-compatible plant is found in the progenies.
