人爲倍數性 林木에 關한 硏究 XII 人爲 4倍體 아까시나무 次代의 減數分裂

Studies on Artificial Polyploid Forest Trees XII. Meiosis in Progenies of Colchitetraploid Robinia pseudoacacia

The chromosome configuration and its behavior in the meiosis of pollen mother cell were observed on four individuals of Robinia pseudoacacia; one was colchitetraploid and the others were one of triploid and two of tetraploid selected from the progenies of colchitetraploid. 1. Chromosome configuration for colchitetraploid, mother tree, was appeared to be slightly irregular and however, most of nuclear plates showed not only chromosome pairing of 20 Ⅱ at metaphaseⅠbut chromosome distribution of 20 at metaphase Ⅱ. 2. At metaphaseⅠ, the numbers of nuclear plates with early separation chromosome were observed with the lowest proportion in the progeny-3 of triploid and with the highest proportion in progeny-5 of tetraploid with the appearance rate of 39.87% 3. At metaphase Ⅱ, the numbers of nuclear plates with early separation chromosome were observed with the lowest proportion in the progeny-16 of tetraploid and with the highest proportion in the progeny -3 of triploid with the appearance of 8.33%. The appearance rate of chromosome bridge between chromosome groups was minimum in the progeny-16 of tetraploid. 4. At anaphaseⅠ, the numbers of nuclear plates with lagging chromosome were observed with the lowest proportion in the progeny-5 of tetraploid and with the highest proportion in the progeny -3 of triploid with the appearance of 27.87%. The maximum appearance rate of chromosome bridge was also in the progeny-3 of the triploid. 5. At anaphase Ⅱ, the number of nuclear plates with lagging chromosome were observed with the lowest proportion in the colchitetraploid, mother tree and with the highest proportion in the progeny-3 of triploid with the appearance rate of 33.45%. The appearance rate of chromosome bridge was maximum in the progeny-3 of triploid. 6. The number of normal pollen sporad was maximum in the colchitetraploid, mother tree.