, Volume 41, Issue 1, pp 361–368 | Cite as

Non-random metaphase I orientation of the chromosomes of a trivalent

  • Marjorir P. Maguire


Relative frequencies were compared of metaphase I orientation for alternate and adjacent distribution of two chromosomes from a trivalent configuration when the third member of the trivalent was of two different types. The two chromosomes whose distribution was studied were a normal sequence maize chromosome 2 and a maize-Tripsacum interchange chromosome. The third chromosome was either: 1. the reciprocal interchange chromosome, segmentally homologous of the normal sequence chromosome (knob (+) plants) or 2. a homologue of the normal sequence chromosome (knob (-) plants). With other conditions apparently similar, adjacent distribution was very significantly greater in knob (+) plants than in knob (-) plants. There seems to be no simple explanation for these results.


Relative Frequency Simple Explanation Normal Sequence Sequence Chromosome Maize Chromosome 
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Copyright information

© Martinus Nijhoff 1970

Authors and Affiliations

  • Marjorir P. Maguire
    • 1
  1. 1.Genetics FoundationUniversity of TexasAustinU.S.A.

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