The genus Allium covers more than 750 species. [1] Allium cepa L. (common onion) and Allium sativum L. (garlic) are considered as the most common and vital Allium species. The importance of some other usefull species depends on the local cultivation and use. [2] Bulbs can be usually stored over several months. However, some bacteria and fungi can infect the stored Allium bulbs and spoil them within a short period of time. [3] In this project, A. cepa, A. sativum, A. altaicum, A. pskmense, A. cornutum, A. fistulosum, and A. ampeloprasum were infected by Fusarium oxysporum, and tested on development of two volatile chemical markers after infection. Healthy and infected bulbs were extracted by ethyl acetate. The extracts were analysed by HPLC/MS to define 2-hexyl-5-methyl-3(2H)-furanone and 2-octyl-5-methyl-3(2H)-furanone. The investigated markers appeared in all infected Alliums species except Allium sativum. Because these compounds only occur after infection, they can be considered as infection markers in many Allium species as well as cultivars.
[1] R. M. Fritsch and M. Keusgen, “Occurrence and taxonomic significance of cysteine sulphoxides in the genus Allium L. (Alliaceae),” Phytochemistry, vol. 67, no. 11, pp. 1127–1135, Jun. 2006.
[2] R. Fritsch and N. Friesen, 1 Evolution, Domestication and Taxonomy. 2002.
[3] H. Shrestha, “A plant monograph on onion,” Sch. Pharm. ans Biomed. Sceinces, vol. Magister S, no. 11, p. 90, 2007.