Helmut E. Freitag (born 1932), German botanist.

IPNI standard form: Freitag

Taxon names authored

(List may be incomplete)

• 47 taxon names authored by Helmut E. Freitag

Publications

(List may be incomplete)

• Freitag, H. & Khani, K. 1987. Salsola griffithii (Chenopodiaceae) comb. nova. — a remarkable species from the sand deserts of SW. Asia. Plant Systematics and Evolution 155(1/4): 49–54. DOI: 10.1007/BF00936286 Reference page. 
• Freitag, H. & Maier-Stolte, M. 1989. The Ephedra-species of P. Forsskal: Identity and typification. Taxon 38(4): 545–556. JSTOR Reference page. 
• Freitag, H., Walter J. & Wucherer W. 1996. Die Gattung Suaeda (Chenopodiaceae) in Österreich, mit einem Ausblick auf die pannonischen Nachbarländer. Annalen des Naturhistorischen Museums in Wien. Serie B, Botanik und Zoologie 98 Suppl.: 343–367. PDF Reference page. 
• Hedge, I.C., Akhani, H., Freitag, H., Kothe-Heinrich, G., Podlech, D., Rilke, S. & Uotila, P. 1997. Chenopodiaceae. In: Rechinger, K.H. (ed.): Flora Iranica Vol. 172. 371 pp., 212 tab., Akademische Druck- u. Verlagsanstalt Graz. Reference page. 
• Freitag, H. & Özhatay, E. 1997. A new subspecies of Salsola canescens (Chenopodiaceae) from SW Anatolia, Turkey. Willdenowia 27: 185–190. DOI: 10.3372/wi.27.2717 Reference page. 
• Freitag, H., Vural, M. & Adıgüzel, N. 1999. A Remarkable New Salsola and Some New Records of Chenopodiaceae from Central Anatolia, Turkey. Willdenowia 29(1–2): 123–139. DOI: 10.3372/wi.29.2911 JSTOR Reference page. 
• Freitag, H. & Duman, H. 2000. An unexpected new taxon of Salsola (Chenopodiaceae) from Turkey. Edinburgh Journal of Botany 57(3): 339–348. DOI: 10.1017/S0960428600000354 ResearchGate Reference page. 
• Freitag, H., Hedge, I.C, Jafri, S.M.H, Kothe-Heinrich, G., Omer, S. & Uotila, P. 2001. Chenopodiaceae. In: Ali, S.I. (ed.): Flora of Pakistan 204. 217 pp., Department of Botany/Missouri Botanical Press, Karachi/St. Louis, ISBN 1-930723-10-5 eFloras. Reference page. 
• Kadereit, G, Borsch, T., Weising, K. & Freitag, H. 2003. Phylogeny of Amaranthaceae and Chenopodiaceae and the evolution of C₄ photosynthesis. International Journal of Plant Sciences 164(6): 959–986. DOI: 10.1086/378649 Reference page. 
• Schütze, P., Freitag, H. & Weising, K. 2003. An integrated molecular and morphological study of the subfamily Suaedoideae Ulbr. (Chenopodiaceae). Plant Systematics and Evolution 239(3): 257–286. DOI: 10.1007/s00606-003-0013-2 Reference page. 
• Lomonosova, M. & Freitag, H. 2003. A new species of Suaeda (Chenopodiaceae) from the Altai, Central Asia. Willdenowia 33: 139–147. DOI: 10.3372/wi.33.33113 PDF Reference page. 
• Kadereit, G., Mucina, L. & Freitag, H. 2006: Phylogeny of Salicornioideae (Chenopodiaceae): Diversification, Biogeography, and Evolutionary Trends in Leaf and Flower Morphology. Taxon 55(3): 617–642. DOI: 10.2307/25065639.Reference page. 
• Freitag, H. & Lomonosova, M. 2006. Typification and identity of Suaeda crassifolia, S. prostrata and S. salsa, three often confused species of Suaeda sect. Brezia (Chenopodiaceae, Suaedoideae). Willdenowia 36: 21–36. DOI: 10.3372/wi.36.36102 Reference page. 
• Kadereit, G., Ball, P.W., Beer, S.S., Mucina, L., Sokoloff, D.D., Teege, P., Yaprak, A.E. & Freitag, H. 2007. A taxonomic nightmare comes true: phylogeny and biogeography of glassworts (Salicornia L., Chenopodiaceae). Taxon 56(4): 1143–1170. DOI: 10.2307/25065909 ResearchGate Reference page. 
• Lomonosova, M., Brandt, R. & Freitag, H. 2008. Suaeda corniculata (Chenopodiaceae) and related new taxa from Eurasia. Willdenowia 38: 81–109. DOI: 10.3372/wi.38.38105 Reference page. 
• Freitag, H. 2011. Typification of Salicornia perennans Willd. (Chenopodiaceae/Amaranthaceae) and the significance of names by Pallas. Willdenowia 41: 231–237. DOI: 10.3372/wi.41.41203 Reference page. 
• Kadereit, G. & Freitag, H. 2011. Molecular phylogeny of Camphorosmeae (Camphorosmoideae, Chenopodiaceae): Implications for biogeography, evolution of C₄-photosynthesis and taxonomy. Taxon 60(1): 51–78. Full text PDF.Reference page. 
• Lomonosova, M. & Freitag, H. 2011. Typification of plant names in Suaedoideae (Chenopodiaceae) published by P. Pallas, C.A. Meyer and A. Bunge. Willdenowia 41(2): 217–229. DOI: 10.3372/wi.41.41202 Reference page. 
• Uotila, P. & Freitag, H. 2011. Salsola boissieri subsp. serpentinicola. In: Greuter, W. & Raab-Straube, E.v. (eds.): Euro+Med Notulae, 5 , Willdenowia, 41(1): 129–138. DOI: 10.3372/wi.41.41117. Reference page. 
• Freitag, H., Brandt, R., Chatrenoor, T. & Akhani, H. 2013. Suaeda iranshahrii, a new species of Suaeda subgenus Brezia (Chenopodiaceae) from the Persian Gulf coasts. Rostaniha 14(1): 68-80. PDF Reference page. 
• Mosyakin, S.L., Rilke, S. & Freitag, H. 2014. (2323) Proposal to conserve the name Salsola (Chenopodiaceae s.str.; Amaranthaceae sensu APG) with a conserved type. Taxon 63(5), 1134–1135. DOI: 10.12705/635.15 Reference page. 
• Freitag, H. & Sennikov, A. 2014. (2256) Proposal to conserve the name Salsola sedoides Pall. against S. sedoides L. (Amaranthaceae/Chenopodiaceae). Taxon 63(1): 186–187. DOI: 10.12705/631.17 Reference page. 
• Brandt, R., Lomonosova, M., Weising, K., Wagner, N. & Freitag, H. 2015. Phylogeny and biogeography of Suaeda subgen. Brezia (Chenopodiaceae/Amaranthaceae) in the Americas. Plant Systematics and Evolution 301(10): 2351–2375. DOI: 10.1007/s00606-015-1233-y Reference page. 
• Freitag, H. & Iamonico, D. 2015. Lectotypification of the name Polycnemum majus (Amaranthaceae s.str.). Phytotaxa 202: 235–236. DOI: 10.11646/phytotaxa.202.3.11 Reference page. 
• Mosyakin, S.L., Freitag, H. & Rilke, S. 2017. Kali versus Salsola: the instructive story of a questionable nomenclatural resurrection. Israel Journal of Plant Sciences 64: 18–30. DOI: 10.1080/07929978.2016.1256135 Reference page. 
• Alonso, M.A., Crespo, M.B. & Freitag, H. 2017. Salicornia cuscoensis (Amaranthaceae/Chenopodiaceae), a new species from Peru (South America). Phytotaxa 319(3): 254–262. DOI: 10.11646/phytotaxa.319.3.4 Reference page. 
• Falatoury, A.N., Iamonico, D. & Freitag, H. 2017. Nomenclature of Caroxylon imbricatum s.lat. (Amaranthaceae / Chenopodiaceae), with a new combination at variety rank. Phytotaxa 331(1): 101–108. DOI: 10.11646/phytotaxa.331.1.8 Reference page. 
• Freitag, H. & Lomonosova, M. 2017. Restoration of Suaeda sect. Helicilla (Chenopodiaceae) and typification of its related taxa. Phytotaxa 323 (1): 51–60. DOI: 10.11646/phytotaxa.323.1.3 Reference page. 

Eponyms

(List may be incomplete)

• Salicornia freitagii Yaprak & Yurdak., 2008
• Salicornia helmutii Piirainen & G.Kadereit, 2017 = Sarcocornia freitagii S.Steffen, Mucina & G.Kadereit, 2009