COLCHICINE-INDUCED CYTOCHIMERAS OF ALLIUM-WAKEGI ARAKI AND THEIR GROWTH-CHARACTERISTICS

Of the 537 shoot apices of Allium wakegi Araki cultured on MS medium with 0.2% colchicine, 85 plants which developed revealed various cytochimeras when their ploidy of three germ layers (L-I, L-II and L-III) were analyzed. The ploidy of the L-I, L-II, and L-III layers was determined by measuring the size of guard cells, counting the number of nucleoli per mesophyll cells, and counting the number of chromosomes in the root tip cells, respectively. From among these cytochimeras, 2-4-4 and 4-2-2 plants were selected and their growth characteristics were compared with those of wholly diploid and tetraploid plants. Tests were made under natural short-day, 13 and 14 hr day length conditions during the winter months. The 4-2-2 plants yielded the greatest number of tillers and leaf blades and formed bulbs earlier than did diploid plants. The 2-4-4 plants were similar to tetraploid ones in nearly all growth characteristics.