of cutting rooted readily and gave additional numbers of the hybrid plants, 

 some of which were treated with colchicine. It wa.s hoped that a doubled 

 number of chromosomes might influence favorably the apparent lack of 

 fertilitv in the hybrids. Several colchicine-treated plants had extra large 

 flowers, large stomata, large pollen, and a greatly increased number of 

 chromosomes, presumably 38. 



By repeated vegetative propagation, a stock of these hybrids with the 

 large flowers was maintained for several years. In all, about sixty plants 

 were grown in the field from the few seeds that could be obtained from 

 the C-treated hybrids. None of the F2 plants appeared promising, though 

 they were markedlv variable. Again no seed was obtained from these 

 second-generation plants due both to sterility and their late flowering in 

 the field. Insects were observed visiting the flowering plants which should 

 have insured adequate pollination. 



The rutabaga. Brassica capestris var. napobrassica, belongs to the cab- 

 bage family and has either 36 or 38 chromosomes depending on the par- 

 ticular variety. This count is approximately twice that of the Chinese x 

 Red Cabbage hybrid. Hence, it seemed feasible to try crosses between the 

 large-flowered colchcine-treated cabbage hybrids and the rutabaga. Recip- 

 rocal crosses between a yellow-fleshed rutabaga I variety not recorded ) and 

 the large-flowered cabbage hybrids were made without difficulty. Ample 

 seeds for hundreds of plants in the next generation were obtained. Thus 

 it was possible to select either leafy-type vegetables or a root crop from 

 among the variable population of plants grown from the seeds of a com- 

 plex ancestry. 



The following discussion will deal with selections directed toward origi- 

 nation of a red Chinese cabbage. Many plants of the complex hybrids, 

 achieved by crossing of the three Brassica species, were loose-leaf types 

 varying in their respective amounts of red and green pigment, but few 

 showed any promising tendency toward a desired firm-heading, red 

 Chinese cabbage. Production of seed from any selected plants became a 

 problem. Seemingly, indifferent progress was being made. So selected 

 plants of the large-flowered Chinese x cabbage hybrids crossed with ruta- 

 baga were backcrossed with Chinese cabbage. Results from this approach 

 were somewhat encouraging, and it might have been continued had not 

 further work proved chat the vegetatively propagated plants of the ori- 

 ginal colchicine-treated Chinese x red cabbage, when used as female parent, 

 could be backcrossed successfully also with Chinese cabbage. Size of 

 flowers varied from plant to plant among these vegetative propagations. 

 Whether some may have been diploid and others tetraploid cannot be told 

 as no counts of chromosomes were made at that time. Regardless, this 

 backcrossing to Chinese cabbage has now progressed through second back- 

 crosses. Continued selection has been made for those young seedlings in 

 a seed flat that showed red stems soon after germination. Only such colored 

 seedlings were carried along for further seed production. In the field in 

 1956, plants that had a firm head similar to the tall slender varieties of 

 Chinese cabbage and which had some red color in their outside leaves were 

 saved for seed production. These selected plants have been sib-pollinated in 

 the greenhouse to learn whether some of them may be carrying factors 

 for intensification of the red color. Certainly, factors for red color ori- 

 ginally in the common cabbage have been transferred by backcrossing into 

 the Chinese cabbage. Further work is needed to produce a satisfactory red 



Chinese cabbage for commercial use. 



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