|NOWICKA, ANNA - Polish Academy Of Sciences|
|SLIWINSKA, ELWIRA - University Of Technology And Life Sciences|
|GRZEBELUS, DARIUSZ - University Of Agriculture - Poland|
|BARANSKI, RAFAL - University Of Agriculture - Poland|
|NOTHNAGEL, THOMAS - Federal Research Centre (FAL)|
|GRZEBELUS, EWA - University Of Agriculture - Poland|
Submitted to: Scientific Horticulture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/17/2016
Publication Date: 6/29/2016
Publication URL: http://handle.nal.usda.gov/10113/62949
Citation: Nowicka, A., Sliwinska, E., Grzebelus, D., Baranski, R., Simon, P.W., Nothnagel, T., Grzebelus, E. 2016. Nuclear DNA content variation within the genus Daucus (Apiaceae) determined by flow cytometry. Scientific Horticulture. 209:132-138. doi: 10.1016/j.scienta.2016.06.023.
Interpretive Summary: The amount of DNA and number of chromosomes in a given cell for any organism is constant, and the same is true among organisms of a given species, but between even closely related species, both DNA content and number of chromosomes can vary quite widely. In this study, these two variables were measured in carrot and several related species in the same genus as carrot. Carrot and its close relatives have 18 chromosome numbers, but some related species have 20 or 22 chromosomes. DNA content varied ~12 % among carrots, but some related species had more than thrice as much DNA per cell as in carrot. This research is of interest to geneticists and plant taxonomists.
Technical Abstract: The genus Daucus (Apiaceae) comprises species from around the world, covering a wide climatic range, and showing great morphological plasticity. Both cultivated and wild forms are described within the genus. The aim of the present study was to estimate the genome size variability in the collection of diploid Daucus species differing in chromosome number (2n = 18, 20 or 22) and originating from various regions of the world. In total, we measured the 2C DNA content in 19 accessions of several wild Daucus species, as well as in 22 wild and 26 cultivated accessions of Daucus carota L. by 'ow cytometry using propidium iodide for DNA staining. Generally, in all accessions, the 2C nuclear DNA content varied over 3-fold, from 0.920 pg in D. carota subsp. maximus (2n = 18, Spain) to 3.019 pg in D. littoralis (2n = 20, Israel). The interspecific genome size differences within wild Daucus species were pronounced and not correlated with chromosome number, e.g. 0.940 pg/2C in D. carota (2n = 18, unknown origin), 2.218 pg/2C in D. broteri (2n = 20, Cyprus), 1.295 pg/2C in D. montevidensis (2n = 22, South America). In the group of 22-chromosome Daucus species we noted high similarity in nuclear DNA content within different accessions of one species, in contrast to the 20-chromosome Daucus species, where intraspecific variation was observed. The nuclear DNA content for non-cultivated forms of D. carota L. varied from 0.920 pg/2C in subspecies maximus (Spain) to 1.154 pg/2C in subspecies halophilus (unknown origin), which reflects a difference at the level of 20%. In turn, in the group of cultivated carrots we observed a high homogeneity among the studied accessions, the 2C nuclear DNA content ranged between 0.950 pg (‘Kuroda type II’, China; ‘Imperial Long Scarlet’, Japan; ‘Koral’, Poland) and 0.977 pg (‘Cape Market’, South Africa). The mean 2C value calculated for both wild and cultivated forms of D. carota L. amounted to 0.973 pg.