allium_fistulosum

Allium fistulosum L. - Liliaceae - 葱 cong (chin.), Welsh onion, Chinese spring onion, Japanese bunching onion, bunching onion, scallion, Frühlingszwiebel, Winterzwiebel, Lauchzwiebel, Schlotten

Perennial herb, up to 1m high, ; leaves subequaling scape, covered with leaf sheaths for ca. 1/3 its length; umbel globose, many flowered, flowers white.
„Cultivated as a vegetable since ancient times [possibly native to W China, but no wild plants have been collected; widely cultivated elsewhere].“
http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200027477

„'Welsh' preserves the original meaning of the Old English word 'welisc', or Old German 'welsche', meaning 'foreign'… The Welsh onion is an ingredient in Asian cuisine, especially in East and Southeast Asia.“
https://en.wikipedia.org/wiki/Allium_fistulosum

„The constituents of the steam volatile oils from two kinds of Allium fistulosum, A. fistulosum var. caespitosum and A. chinense, have been investigated by GC and spectral techniques… dipropyl disulphide comprised ca 28% of A. fistulosum oil, ca 23% of A. fistulosum var. caespitosum oil and ca 30% of A. chinense oil. A. fistulosum oil was characterized by a large quantity of tridecan-2-one (ca 52%) and 2,3-dihydro-2-octyl-5-methylfuran-3-one (ca 16%).“
[Sulphides and furanones from steam volatile oils of Allium fistulosum and Allium chinense., Kameoka, H., Iida, H., Hashimoto, S., Miyazawa, M., Phytochemistry, Vol.23(1), 1984, 155-158]

„Volatile components were isolated from Welsh onions and scallions by solvent extraction at ambient temperatures and analyzed by GC and GC-MS. There were 67 volatile components identified, including 12 novel polysulfides. Methyl methanethiosulfinate and 10 dialk(en)yl thiosulfonates were among those volatiles in Welsh onion and scallion extracts. These thiosulfinates and thiosulfonates were not previously identified in their distilled oils, probably due to their instability to heat.“
[Volatile constituents of the solvent extracts of Welsh onions (Allium fistulosum L. variety Maichuon) and scallions (A. fistulosum L. variety Caespitosum)., Kuo, M.C., Ho, C.T., Journal of Agricultural and Food Chemistry, Vol.40(10), 1992, 1906-1910]

The headspace components the plant „… was extracted with solid-phase microextraction (SPME) and analysed by gas chromatography-mass spectrometry (GC-MS). The main volatile components of A. fistulosum were dipropyl disulphide (relative contents: 67%), 1-propenyl propyl disulphide (23%) and dipropyl trisulphide (6%).“
[Onion aphid (Neotoxoptera formosana) attractants, in the headspace of Allium fistulosum and A. tuberosum leaves., Hori, M., Journal of Applied Entomology, Vol.131(1), 2007, 8-12]

Zorn, J., Oskamp, D.L., Vervolg op de Afbeeldingen der artseny-gewassen met derzelver Nederduitsche en Latynsche beschryvingen, vol.1, t.26 (1813)
http://plantgenera.org/species.php?id_species=39965