Gustaf Otto Rosenberg, termed Otto Rosenberg in publications, born June 9, 1872, in

Gothenburg Gothenburg ( ; ) is the List of urban areas in Sweden by population, second-largest city in Sweden, after the capital Stockholm, and the fifth-largest in the Nordic countries. Situated by the Kattegat on the west coast of Sweden, it is the gub ...

Sweden Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...

, died November 30, 1948, was a Swedish botanist; son of Johan Olof Rosenberg. Rosenberg studied in

Uppsala Uppsala ( ; ; archaically spelled ''Upsala'') is the capital of Uppsala County and the List of urban areas in Sweden by population, fourth-largest city in Sweden, after Stockholm, Gothenburg, and Malmö. It had 177,074 inhabitants in 2019. Loc ...

Stockholm Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...

and

Bonn Bonn () is a federal city in the German state of North Rhine-Westphalia, located on the banks of the Rhine. With a population exceeding 300,000, it lies about south-southeast of Cologne, in the southernmost part of the Rhine-Ruhr region. This ...

, he gained a bachelor's degree at the

University of Uppsala Uppsala University (UU) () is a public research university in Uppsala, Sweden. Founded in 1477, it is the oldest university in Sweden and the Nordic countries still in operation. Initially founded in the 15th century, the university rose to s ...

in 1895, and a PhD in

in 1899 where he studied under

Eduard Strasburger Eduard Adolf Strasburger (1 February 1844 – 18 May 1912) was a Polish- German professor and one of the most famous botanists of the 19th century. He discovered mitosis in plants. Life Eduard Strasburger was born in Warsaw, Congress Poland, t ...

(1844–1912). His PhD thesis addressed the cytological changes that occur in the cells of the Sundew plant (''

Drosera ''Drosera'', which is commonly known as the sundews, is one of the largest genus, genera of carnivorous plants, with at least 194 species. 2 volumes. These members of the family Droseraceae lure, capture, and digest insects using stalked mucil ...

'') when they are irritated. Also in 1899, he became an associate professor of botany at the University of Stockholm. Rosenberg worked at the Botanical Institute in Stockholm from 1904 and was promoted to a professorship in plant anatomy and cytology in 1911, at the same university. Later, Rosenberg studied meiosis in the hybrid of ''Drosera longifolia'' crossed with ''D. rotundifolia'', this was the first cytologically examined plant hybrid. The former of the two parent species contained 40 chromosomes, the latter 20; however, the near-sterile hybrid (''D. obovata'') contained 30 chromosomes. This ''Drosera'' 'scheme’ was almost certainly the first example of the parents of a hybrid being identified through the analysis of chromosome pairing during

meiosis Meiosis () is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, the sperm or egg cells. It involves two rounds of division that ultimately result in four cells, each with only one c ...

.ROSENBERG, O. 1909b. Cytologische und morphologische Studien an Drosera longifolia x rotundifolia. Kungliga Svenska Vetenskaps-Akademiens Skrifter Naturskyddsarenden Handlingar, 43: 1-64. Rosenberg's writings dealt mainly in cytology and plant embryology and he became very prominent in these fields. In 1917 he was elected a member of the

Royal Swedish Academy of Sciences The Royal Swedish Academy of Sciences () is one of the Swedish Royal Academies, royal academies of Sweden. Founded on 2 June 1739, it is an independent, non-governmental scientific organization that takes special responsibility for promoting nat ...

and, in 1925, a member of the

Royal Danish Academy of Sciences and Letters The Royal Danish Academy of Sciences and Letters ({{Langx, da, Det Kongelige Danske Videnskabernes Selskab or ''Videnskabernes Selskab'') is a Danish academy of science. The Royal Danish Academy was established on 13 November 1742, and was create ...

. Rosenberg became a Commander of the

Order of the Polar Star The Royal Order of the Polar Star (Swedish language, Swedish: ''Kungliga Nordstjärneorden''), sometimes translated as the Royal Order of the North Star, is a Swedish order of chivalry created by Frederick I of Sweden, King Frederick I on 23 F ...

, November 22, 1932.

References

{{DEFAULTSORT:Rosenberg, Otto 1872 births 1948 deaths People from Gothenburg 20th-century Swedish botanists University of Bonn alumni Swedish scientists