Genomic changes in generations of synthetic rapeseed-like allopolyploid grown under selection Alexandra V. Amosova . Lyudmila V. Zemtsova . Olga Yu. Yurkevich . Elena N. Zhidkova . Tomasz Ksia ˛ _ zczyk . Natalia G. Shostak . Anatoly A. Muravlev . Anna M. Artemyeva . Tatiana E. Samatadze . Svyatoslav A. Zoshchuk . Olga V. Muravenko Received: 27 June 2017 / Accepted: 23 August 2017 / Published online: 31 August 2017 Ó Springer Science+Business Media B.V. 2017 Abstract Resynthesized Brassica napus L. is an important source for broadening genetic diversity and producing lines with desired characteristics. It is also a fine model to study the processes of genomic reorga- nizations in recently formed polyploids. We firstly performed molecular cytogenetic characterization of newly resynthesized rapeseed (B. rapa ssp. narinosa 9 B. oleracea ssp. capitata) and its parental species, and also examined genomic changes in hybrids of the succeeding generations grown under pressure of selection of yellow-seeded progeny. For karyotype studies, FISH/GISH with 45S, 5S rDNA, C genome specific BoB014O06 BAC clone and genomic DNA of parental B. rapa was performed. Synthetic S0–S2 hybrids had common rapeseed karyotypes (2n = 38) including 14 loci of 45S rDNA sites and 10 loci of 5S rDNA. Progeny selection led to gradual deletion of C genome chromosomes in hybrid karyotypes. So, in karyotypes of S6 and S7 hybrids, the chromosome number was reduced to 2n = 20–22, and only chro- mosomes of A genome bearing 10–13 loci of 45S rDNA and 8–10 loci of 5S rDNA, variations in chromosome number, chromosome rearrangements as well as examples of trisomy and monosomy were revealed. Our findings indicate an enhanced genome instability in resynthesized rapeseed lines developed under the pressure of selection which might lead to chromosome rearrangements or/and deletions and even elimination of the whole parental genome in hybrids in succeeding generations. The approach can be useful for the development of rapeseed lines with A. V. Amosova (&) Á L. V. Zemtsova Á O. Yu. Yurkevich Á N. G. Shostak Á T. E. Samatadze Á S. A. Zoshchuk Á O. V. Muravenko Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilov 32, Moscow, Russian Federation 19991 e-mail: amomar@mail.ru E. N. Zhidkova Lipetsk State Pedagogical P. Semenov-Tyan-Shansky University, Federal Agency for Scientific Organizations, Lenin 42, Lipetsk, Russian Federation 398020 T. Ksia ˛ _ zczyk Institute of Plant Genetics, Polish Academy of Sciences, Strzeszyn ´ska 34, 60-479 Poznan ´, Poland A. A. Muravlev All-Russian Rapeseed Research Institute, Federal Agency for Scientific Organizations, Boyevoy proezd 26, Lipetsk, Russian Federation 398037 A. M. Artemyeva N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR), Federal Agency for Scientific Organizations, B. Morskaya 42-44, Saint Petersburg, Russian Federation 190000 123 Euphytica (2017) 213:217 DOI 10.1007/s10681-017-2009-y