Gen-ichi Koidzumi (小泉 源一, Koizumi Gen'ichi, 1 November 1883 – 21 December 1953) was a Japanese botanist, author of several papers and monographs on phytogeography including work on roses and Amygdaloideae (Rosaceae), maples (Aceraceae), mulberries (the genus Morus), and many other plants. His name is sometimes transliterated as Gen’ichi or Gen-Iti, or as Koizumi.
|Born||1 November 1883|
|Died||21 December 1953(aged 70)|
|Author abbrev. (botany)||Koidz.|
- 1956. Plants of Jaluit Island (Pacific surveys report / U.S. Army, Corps of Engineers, Far East)
- 1952. The Big Button Palm which produces the ivory nut ([Reports] - USGS, Pacific Geological Surveys)
- 1930. Florae Symbolae Orientali-Asiaticae sive Contributions to the Knowledge of the Flora of Eastern Asia. Kyoto, Japan., 115 pp.
- 1928. Plantae Novae Amami-Ohsimensis nec non Insularum adjacentium: 1 Phytogeographical notes on the flora of the Loochoo Archipelago. 2 Description of new species. 19 pp.
- Nakaike, T, A Yamamoto. 2002. Enumeration of the Latin names of pteridophytes published by Dr. Gen'ichi Koidzumi. Journal of Phytogeography and Taxonomy 50 (1): 63–68. ISSN 0388-6212