2n=27染色体を持つライおよびその次代植物

抄録

1. In the present report, external characters, seed fertility and meiosis in PMC's of hypo-autotetraploid rye 2n=27 bhomosomes were described. 2. Hypo-autotetraploid plant was inferior in lengths of sterrt and percentage of seed fertility to both parental eu-autotetraploid and original diploid. 3. 3 members of 27 chromosomes of the hypoautotetrapfoid have each a satellite at one end, while in eu-autotetra.ploid 4 members of the 28 chromosomes have each a satellite. 4. At the heterotypic metaphase of P MC's of hypo-autotetraploid 1-3 univalents and 12-13 bivalents were observed. 5. The distribution of chromosomes to the opposite poles at the heterotypic ana-telophase proceeded normally, consequently in most cases chromosomes were distributed to 14 : 13. 6. In filial generation of hypo-autotetraploid plant having 2 n=26 chromosomes, numbers of somatic chromosomes of 18 individuals was observed to be 26-29 (Table 2). Seed fertility of these 18 filial plants was very low in percentage or almost sterile. 7. Eu-autotetraploid rye has 2 n=28 chromosomes forming 7 sets and each of them consisting of 4 homologous chromosomes, while in hypo-autotetraploid plant having 2 n=27, one chromosomes is lacking in a set, or in other words, the set under consideration consists of 3 homologous chromosomes instead of 4 and may be a sort of trisomic. Accordingly it may bc called "trisomcautotetraploid ". Trisomo-autotetraploid prefixed with morio-, di-, tri-, etc. may be employed according as the number of trisomic sets.