STERILITY IN SUCCESSIVE BACKCROSSES OFRAPHANOBRASSICA(2n = 4x = 36) WITH RECURRENTBRASSICA OLERACEA(2n = 2x = 18)

Publisher Website
Google Scholar
Abstract
A series of crosses to develop cytoplasmic male sterility in the cole crops by transferring the Brassica oleracea L. (2n = 18) genome into the cytoplasm of radish (Raphanus sativus L., 2n = 18) through the amphidiploid Raphanobrassica (2n = 4x = 36) was terminated because of complete seed sterility of the only two BC6hybrid plants obtained. There was no improvement of seed set in six backcrosses to diploid B. oleracea, and the chromosome numbers of the few plants producing seeds were higher than expected, frequently being close to the triploid number (2n = 3x = 27) of the BC1. Zygotes with less than two radish chromosomes were not found; those with less than four were few; and those with less than six rarely produced offspring.