Jessica Klekar (TU Dresden)
Comparison of selected beet species of the sections Beta (upper row) and Corollinae (lower row). All plants were ultivated under greenhouse conditions, adult plants are older than one year, young plants are about four months old. Images: J. Klekar
Jessica Klekar's Master thesis was awarded with the Prize for the Best Plant Science Master Thesis, which was carried out at TU Dresden in the year 2021
Title: Karyotype evolution within the genus Beta
By barcoding of the chromosomes of sugar beet and closely related species, it was possible to detect major structural changes as species boundaries.
Cytogenetics, as an important branch of genetics, deals with chromosome structure and composition in order to link these to phenotypic phenomena. In most plants, chromosomes cannot be distinguished on the basis of simple staining so that karyotyping is not readily possible. To address this lack for sugar beet (Beta vulgaris) and related wild beets, we developed a two-colour barcode for karyotyping the nine chromosome pairs of sugar beet through fluorescent in situ hybridization (FISH) and applied it to the genomes of closely related species. In addition to confirming the pericentric inversion on chromosome 5 of Beta patula, a paracentric inversion on chromosome 7 of Beta macrocarpa was identified using an altered barcode. The knowledge gained about the structural chromosomal differences between the species should not be understood exclusively as species boundaries, but may also be indications of the high heterogeneity of the wild species. This could become relevant for breeding if resistance genes to diseases can be identified on the affected chromosomes of the wild species, which are not (or no longer) present in the cultivated sugar beet.
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Jessica Klekar conducted this work at the Chair of Plant Cell and Molecular Biology in the research group of Dr. Tony Heitkam.