Cytological studies of the two-spotted spider mite Tetranychus urticae Koch (Tetranychidae, trombidiformes). I: Meiosis in eggs

  title={Cytological studies of the two-spotted spider mite Tetranychus urticae Koch (Tetranychidae, trombidiformes). I: Meiosis in eggs},
  author={C. Feiertag-Koppen},
Meiosis in eggs of Tetranychus urticae Koch is described. The two maturation divisions result in (a) a haploid female pronucleus consisting of three karyomeres; — (b) a divided first polar body in which the chromosomes change into karyomeres; — (c) a second polar body, entering a new mitosis which is blocked in metaphase. Irradiation of adult females produced chromosome fragments in the meiotic divisions. The fragments behave as intact chromosomes which proves that during meiosis a diffuse… Expand
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