Klein, Joanna (5 September 2017). "Why Onions Make You Cry". The New York Times. Archived from the original on 17 April 2018 . Retrieved 16 April 2018.

Cantisani, C; Visconti, B; Paolino, G; Frascani, F; Tofani, S; Fazia, G; Calvieri, S (2014). "Unusual food allergy: Alioidea allergic reactions overview". Recent Patents on Inflammation & Allergy Drug Discovery. 8 (3): 178–84. doi: 10.2174/1872213X08666141107170159. PMID 25381903. Onions are toxic to dogs, cats, guinea pigs, and many other animals. [53] [54] Cultivation Large-scale onion cultivation Freshly cut onions often cause a stinging sensation in the eyes of people nearby, and often uncontrollable tears. This is caused by the release of a volatile liquid, syn-propanethial-S-oxide and its aerosol, which stimulates nerves in the eye. [7] This gas is produced by a chain of reactions which serve as a defence mechanism: chopping an onion causes damage to cells which releases enzymes called alliinases. These break down amino acid sulfoxides and generate sulfenic acids. A specific sulfenic acid, 1-propenesulfenic acid, is rapidly acted on by a second enzyme, the lacrimatory factor synthase (LFS), producing the syn-propanethial-S-oxide. [7] This gas diffuses through the air and soon reaches the eyes, where it activates sensory neurons. Lacrimal glands produce tears to dilute and flush out the irritant. [39] Daniel (last working) link: http://danielas3rtn54uwmofdo3x2bsdifr47huasnmbgqzfrec5ubupvtpid.onion/ 9. Numbers StationSavoy, Daniel (2017). The Globalization of Renaissance Art: A Critical Review. BRILL. p.55. ISBN 9789004355798 . Retrieved 21 January 2018– via Google Books. Abdel-Maksouda, Gomaa; El-Aminb, Abdel-Rahman (2011). "A review on the materials used during the mummification process in ancient Egypt" (PDF). Mediterranean Archaeology and Archaeometry. 11 (2): 129–150. Archived (PDF) from the original on 8 March 2014 . Retrieved 13 September 2013. The amount of sulfenic acids and lacrimal factor released and the irritation effect differs among Allium species. In 2008, the New Zealand Institute for Crop and Food Research created "no tears" onions by genetic modification to prevent the synthesis of lachrymatory factor synthase in onions. [41] One study suggests that consumers prefer the flavour of onions with lower LFS content. [42] Since the process impedes sulfur ingestion by the plant, some find LFS− onions inferior in flavour. [43] The triploid onion is a hybrid species with three sets of chromosomes, two sets from A. cepa and the third set from an unknown parent. [3] :19 Various clones of the triploid onion are grown locally in different regions, such as 'Ljutika' in Croatia, and 'Pran', 'Poonch', and 'Srinagar' in the India-Kashmir region. 'Pran' is grown extensively in the northern Indian provinces of Jammu and Kashmir. There are very small genetic differences between 'Pran' and the Croatian clone 'Ljutika', implying a monophyletic origin for this species. [73]

Onions are best cultivated in fertile soils that are well-drained. Sandy loams are good as they are low in sulphur, while clayey soils usually have a high sulphur content and produce pungent bulbs. Onions require a high level of nutrients in the soil. Phosphorus is often present in sufficient quantities, but may be applied before planting because of its low level of availability in cold soils. Nitrogen and potash can be applied at regular intervals during the growing season, the last application of nitrogen being at least four weeks before harvesting. [55] Music streaming on the dark web – what could go wrong? Absolutely nothing; Deep Web Radio is all about tunes and enriching your dark web experience. So, hook up those headphones to your laptop, choose a radio station, and browse away. USDA, NRCS (n.d.). " Allium cepa". The PLANTS Database (plants.usda.gov). Greensboro, North Carolina: National Plant Data Team . Retrieved 31 March 2013. Considerable differences exist between onion varieties in phytochemical content, particularly for polyphenols, with shallots having the highest level, six times the amount found in Vidalia onions. [35] Yellow onions have the highest total flavonoid content, an amount 11 times higher than in white onions. [35] Red onions have considerable content of anthocyanin pigments, with at least 25 different compounds identified representing 10% of total flavonoid content. [35]Dark.fail (last working) link: http://darkfailenbsdla5mal2mxn2uz66od5vtzd5qozslagrfzachha3f3id.onion/ 19. The CIA Guinea hen weed and honey garlic contain a similar lachrymatory factor. [49] Synthetic onion lachrymatory factor has been used in a study related to tear production, [50] and has been proposed as a nonlethal deterrent against thieves and intruders. [51] [52] Onion bulbs used for planting and seeds Toxicity to animals Allium × proliferum". Germplasm Resources Information Network. Agricultural Research Service, United States Department of Agriculture . Retrieved 21 February 2011.