배추 청방약근${\times}$무우 울산재래의 속간잡동에 대한 세포유전학적 연구

Intergeneric crossings between the inbred line of Brassica pekinensis var. Chongbangkokun and inbred line of Raphanus sativus var. Oolsanjaelae were made using Brassica as female plant, and obtained two individuals of intergeneric hybrids. Morphological characters of the two F1 hybrids are mostly intermediate of the two parental species, and their somatic chromosome number is 19. Meiotic behaviors of the parental plants were normal, while those of F1 plants were extremely irregular. The mean pairing frequencies per cell of hybrids are 1.09II＋16.811(examined in May), and 1.76II＋15.47i(examined in June). Majority of the pollen grain of parent species are normal, whereas those of F1's are invariably abortive. No seed setting was obtained in the hybrid plants left in the open field.