A Cytogenetical Study on the Origin of Twin Plants Found in the Progeny of an Aneuploid in Brassica napus L.

Abstract

Six pairs of twins were found in the progeny of an aneuploid (2n=67) in Brassica napus L. var. oleifera DC. The frequency of occurrence of twins was 9.09%. Five pairs had chromosomes between 60 and 68 inclusive. These were presumably of sexual origin. One pair, both members of which had 40 chromosomes, probably originated from the cleavage of a reduced unfertilized cell which developed parthenogenetically.