caa a22 4500 467900841 CHVBK 20180406152817.0 cr unu---uuuuu 170328e20061001xx s 000 0 eng 10.1007/s00299-006-0170-1 doi (NATIONALLICENCE)springer-10.1007/s00299-006-0170-1 Extra divisions and nuclei fusions in microspores from Brassica allohexaploid (AABBCC) × Orychophragmus violaceus hybrids [Elektronische Daten] [Xian-Hong Ge, Zai-Yun Li] Abnormal meiosis and microspore development and related defective mutants have often been reported in plants and wide hybrids. Here extra divisions and nuclei fusions were observed to occur in microspore nuclei of partial hybrids between synthetic Brassica hexaploid (2n=54, AABBCC) and another crucifer Orychophragmus violaceus (2n=24). Abnormal spindle were formed and chromosomes were separated into several nuclei of variable sizes after bi-, or multi-polar divisions in the four cells of tetrads. As a consequence, more than eight mini-microspores of different sizes were produced by one tetrad. Genomic in situ hybridization results indicated that no chromosome replication occurred during such divisions. In some tetrads, the four nuclei were fused to form one large cell with increased chromosome number. The extra divisions or fusions appeared only in some flower buds of one plant, some anthers in the same buds, or even in individual cells of tetrads. The possible mechanisms behind these cytological phenomena are discussed. Springer-Verlag, 2006 Brassica allohexaploid nationallicence Cell cycle nationallicence Cell fusion nationallicence Meiosis nationallicence Microspore nationallicence Multi-polar division nationallicence Orychophragmus violaceus nationallicence Ge Xian-Hong National Key Laboratory of Crop Genetic Improvement, National Center of Crop Molecular Breeding Technology, National Center of Oil Crop Improvement (Wuhan), Huazhong Agricultural University, 430070, Wuhan, P. R. China aut Li Zai-Yun National Key Laboratory of Crop Genetic Improvement, National Center of Crop Molecular Breeding Technology, National Center of Oil Crop Improvement (Wuhan), Huazhong Agricultural University, 430070, Wuhan, P. R. China aut Plant Cell Reports Springer-Verlag 25/10(2006-10-01), 1075-1080 0721-7714 25:10<1075 2006 25 299 https://doi.org/10.1007/s00299-006-0170-1 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00299-006-0170-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ge Xian-Hong National Key Laboratory of Crop Genetic Improvement, National Center of Crop Molecular Breeding Technology, National Center of Oil Crop Improvement (Wuhan), Huazhong Agricultural University, 430070, Wuhan, P. R. China aut NATIONALLICENCE 700 1- Li Zai-Yun National Key Laboratory of Crop Genetic Improvement, National Center of Crop Molecular Breeding Technology, National Center of Oil Crop Improvement (Wuhan), Huazhong Agricultural University, 430070, Wuhan, P. R. China aut NATIONALLICENCE 773 0- Plant Cell Reports Springer-Verlag 25/10(2006-10-01), 1075-1080 0721-7714 25:10<1075 2006 25 299 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer