Meiotic studies carried out on seven plants/clones of Tradescantia spathacea did not show the expected ring of 12 chromosomes in any of the 1765 cells studied at diakinesis (1202 cells) and metaphase I (563 cells). While at diakinesis the chromosomes resolved into chain configurations of all lengths ranging from one through 12 chromosomes, with the mean per cell being 2.47 ± 1.28, at metaphase I chains carrying up to 10 chromosomes were seen and the mean per cell was 4.18 ± 1.47. However, the larger chains were not the most frequent configurations observed at the two stages. Bivalents and univalents were the most frequent configurations observed in 38.68 and 43.92% cells at diakinesis and 63.94 and 57.72% cells at metaphase I, followed by chains of 10 (29.95% cells) and chains of three (51.50% cells) at the two stages, respectively. The larger chains, though visible at both the meiotic stages, varied significantly in the centromere orientation patterns. While at diakinesis they predominantly showed linear or indifferent orientation, at metaphase I 83.25% chains showed alternate orientation, with the rest showing linear and/or indifferent orientation. A high frequency of alternate orientation was observed in chains of three chromosomes (93.93%), followed by the chains of five and four, where 74.19 and 71.27% chains appeared in alternate orientation, respectively. In 4.97% cells with two chains of six chromosomes each, contrasting behavior was noticed in the two chains in respect of orientation. While one chain appeared zigzagged with alternate centromeres facing the same pole, the other chain invariably appeared in linear configuration. As a result of complex configurations at metaphase I and the high frequency of univalents, anaphase I segregation of chromosomes was highly irregular with 84% cells showing 1-3 lagging chromosomes. The average pollen viability determined for the seven clones studied was very low (17.87 ± 2.57%). The probable cause(s) of the different behaviors of the chain multiples at the two meiotic stages is discussed.

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