title: [Cytogenetical comparison of restorers TP-4 and D minghui63 and maintainer D46B of autotetraploid rice].
abstract: Cytogenetical comparison was made between high seed set restorers TP-4 and D minghui63 and eminent maintainer line D46B of autotetraploid rice. The meiosis observation demonstrated the genomes of our autotetraploid materials were all 2n = 48, the same as those in mitosis observation. Low percentages of univalent and trivalent in metaphase I (MI) of restorers TP-4 and D minghui63 and in metaphase I (MI) of maintainer line D46B of autotetraploid rice were observed. And the percentages of chromosome pairing were all over 99%, showing eminent cytological character. The frequency of TP-4 and D minghui63 in metaphase I (MI) was 2.00/PMC and 2.26/PMC, respectively. However the frequency of D46B was 6.00/PMC, significantly higher than those of TP-4 and D minghui63. It indicated that the maintainer D46B has better chromosome pairing capability in metaphase I (MI). While, the frequency of lagging chromosomes of the maintainer D46B in anaphase I (AI) was 10.62%, significantly lower than that of TP-4 (19.44%) or D minghui63 (23.14%), and it was close to the level of diploid control (7.30%). In telophase I (TI), maintainer D46B exhibited a lower frequency of microkernel, and in telophase II (TII) the frequency of normal quartered microspore of maintainer D46B was not only higher than that of TP-4 or D minghui63 but also than that of diploid control. The percentage of the cell observed chromosome lagging in A1 and the percentage of abnormal cell in TI showed a greatly significant positive correlation. That may demonstrate chromo some separation in anaphase I (AI) and microkernel formation in telophase I (TI) are controlled by the same dominant single gene or the major gene of QTL.
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China. lwb33123@163.com
authors.forename: Wen-Bo
authors.initials: WB
authors.lastname: Long
authors.forename: Li
authors.initials: L
authors.lastname: Luan
authors.forename: Xing
authors.initials: X
authors.lastname: Wang
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Liu
authors.forename: Sheng-Bin
authors.initials: SB
authors.lastname: Tu
authors.forename: Fan-Lun
authors.initials: FL
authors.lastname: Kong
authors.forename: Tao
authors.initials: T
authors.lastname: He
mesh_terms: D002453:Cell Cycle / Q000502:physiology*; D002455:Cell Division; D023902:Chromosome Pairing; D032461:Chromosomes, Plant; D012275:Oryza / Q000166:cytology / Q000235:genetics*; D011123:Polyploidy