Basil is an annual, or sometimes perennial, herb. Depending on the variety, plants can reach heights of between 30 and 150 centimetres (1 and 5 feet).[6] Basil leaves are glossy and ovulate, with smooth or slightly toothed edges that typically cup slightly; the leaves are arranged oppositely along the square stems.[7] Leaves may be green or purple. Its flowers are small and white, and grow from a central inflorescence, or spike, that emerges from the central stem atop the plant.[citation needed] Unusual among Lamiaceae, the four stamens and the pistil are not pushed under the upper lip of the corolla, but lie over the inferior lip. After entomophilous pollination, the corolla falls off and four round achenes develop inside the bilabiate calyx.[citation needed]
The exact taxonomy of basil is uncertain due to the immense number of cultivars, its ready polymorphy, and frequent cross-pollination (resulting in new hybrids) with other members of the genus Ocimum and within the species. Ocimum basilicum has at least 60 varieties, which further complicates taxonomy.[5]
Cultivars
Most basils are cultivars of sweet basil. Most basil varieties have green leaves, but a few are purple, such as, 'Purple Delight'.
Napolitano basil, also known as Napoletano basil, Neapolitan basil, Mammoth basil, Bolloso Napoletano basil, Napolitano Mammoth-Leafed basil, or Italian Large-Leaf basil (Ocimum basilicum)
Spice basil (Ocimum basilicum × O. americanum), which is sometimes sold as holy basil
Etymology
The name "basil" comes from the Latinbasilius, and the Greekβασιλικόν φυτόν (basilikón phytón), meaning "royal/kingly plant", possibly because the plant was believed to have been used in production of royal perfumes.[21] Basil is likewise sometimes referred to in French as "l'herbe royale" ('the royal herb').[22] The Latin name has been confused with basilisk, as it was supposed to be an antidote to the basilisk's venom.[21]
Distribution and habitat
Basil is native to India and other tropical regions stretching from Africa to South East Asia, but has now become globalized due to human cultivation.[5]
Basil is sensitive to cold, with best growth in hot, dry conditions. It behaves as an annual if there is any chance of a frost. However, due to its popularity, basil is cultivated in many countries around the world. Production areas include countries in the Mediterranean area, those in the temperate zone, and others in subtropical climates.[23][page needed]
In Northern Europe, Canada, the northern states of the U.S., and the South Island of New Zealand, basil grows best if sown under glass in a peat pot, then planted out in late spring/early summer[24] (when there is little chance of a frost); however, it can also thrive when planted outside in these climates. Additionally, it may be sown in soil once chance of frost is past. It fares best in well-drained soil with direct exposure to the sun.[citation needed]
Although basil grows best outdoors, it can be grown indoors in a pot and, like most herbs, will do best on a sun-facing windowsill, kept away from extremely cold drafts. A greenhouse or row cover is ideal if available. It can, however, even be grown in a basement under fluorescent lights. Supplemental lighting produces greater biomass and phenol production, with red + blue specifically increasing growth and flower bud production. UV-B increases the volatiles in O. basilicumessential oil, which has not been reproducible in other plants, and so may be unique to the genus or even to this species.[25]
Basil plants require regular watering, but not as much attention as is needed in other climates. If its leaves have wilted from lack of water, it will recover if watered thoroughly and placed in a sunny location. Yellow leaves towards the bottom of the plant are an indication that the plant has been stressed; usually this means that it needs less water, or less or more fertilizer.[26] Basil can be propagated reliably from cuttings with the stems of short cuttings suspended in water for two weeks or until roots develop.[citation needed]
Pruning, flowering, and seeding
Once a stem produces flowers, foliage production stops on that stem, the stem becomes woody, and essential oil production declines. To prevent this, a basil-grower may pinch off any flower stems before they are fully mature. Because only the blooming stem is so affected, some stems can be pinched for leaf production, while others are left to bloom for decoration or seeds. Picking the leaves off the plant helps promote growth, largely because the plant responds by converting pairs of leaflets next to the topmost leaves into new stems.[citation needed]
Once the plant is allowed to flower, it may produce seed pods containing small black seeds, which can be saved and planted the following year. If allowed to go to seed, a basil plant will grow back the next year.[citation needed]
Diseases
Basil suffers from several plant pathogens that can ruin the crop and reduce yield. Fusarium wilt is a soil-borne fungal disease that will quickly kill younger basil plants. Seedlings may be killed by Pythiumdamping off. A common foliar disease of basil is gray mold caused by Botrytis cinerea; it can cause infections post-harvest and is capable of killing the entire plant. Black spot can be seen on basil foliage and is caused by the fungigenusColletotrichum. Downy mildew caused by Peronospora belbahrii is a significant disease, as first reported in Italy in 2003.[27] It was reported in the Florida in 2007 and by 2008 had spread along the eastern United States, reaching Canada.[28][29] Basil cultivars resistant to P. belbahrii have been developed.[30]
Basil is most commonly used fresh in recipes. In general, it is added last, as cooking quickly destroys the flavor. The fresh herb can be kept for a short time in plastic bags in the refrigerator, or for a longer period in the freezer, after being blanched quickly in boiling water.[citation needed]
Leaves and flowers
The most commonly used Mediterranean basil cultivars are "Genovese", "Purple Ruffles", "Mammoth", "Cinnamon", "Lemon", "Globe", and "African Blue". Basil is one of the main ingredients in pesto, an Italian sauce with olive oil and basil as its primary ingredients. Many national cuisines use fresh or dried basils in soups and other foods, such as to thicken soups. Basil is commonly steeped in cream or milk to create flavor in ice cream or chocolate truffles.[citation needed]
Lemon basil has a strong lemony smell and flavor due to the presence of citral. It is widely used in Indonesia, where it is called kemangi and served raw as an accompaniment to meat or fish.[citation needed]
Studies of the essential oil have shown insecticidal and insect-repelling properties,[36] including potential toxicity to mosquitos.[37] The essential oil is found by Huignard et al. 2008 to inhibit electrical activity by decreasing action potential amplitude, by shortening the post hyperpolarization phase, and reducing the action frequency of action potentials. In Huignard's opinion this is due to the linalool and estragole, the amplitude reduction due to linalool, and the phase shortening due to both.[38]
^ abcdefgSimon, James E (23 February 1998). "Basil". Center for New Crops & Plant Products, Department of Horticulture, Purdue University, West Lafayette, IN. Archived from the original on 2 May 2017. Retrieved 22 January 2018.
^Kandil, M. A. M.; Khatab, M. E.; Ahmed, S. S.; Schnug, E (2009). "Herbal and essential oil yield of Genovese basil (Ocimum basilicum L.) grown with mineral and organic fertilizer sources in Egypt". Journal für Kulturpflanzen. 61 (12): 443–449.
^Britannica, The Editors of Encyclopaedia. "basil (herb)". Encyclopedia Britannica. Retrieved 21 December 2023.
^Lee, Seung-Joo; Umano, Katumi; Shibamoto, Takayuki; Lee, Kwang-Geun (2005). "Identification of Volatile Components in Basil (Ocimum basilicum L.) and Thyme Leaves (Thymus vulgaris L.) and Their Antioxidant Properties". Food Chemistry. 91: 131–137. doi:10.1016/j.foodchem.2004.05.056.
^Eberhard Breitmaier (22 September 2006). Terpenes: Flavors, Fragrances, Pharmaca, Pheromones. John Wiley & Sons. pp. 11–. ISBN978-3-527-31786-8. Archived from the original on 12 October 2013. Retrieved 2 August 2013. Acyclic monoterpenoid trienes such as p-myrcene and configurational isomers of p- ocimene are found in the oils of basil (leaves of Ocimum basilicum, Labiatae), bay (leaves of Fimenta acris, Myrtaceae), hops (strobiles of Humulus lupulus, ...
^Md Shahidul Islam (4 February 2011). Transient Receptor Potential Channels. Springer. pp. 50–. ISBN978-94-007-0265-3. Archived from the original on 12 October 2013. Retrieved 2 August 2013. Eugenol is a vanilloid contained in relatively high amounts in clove oil from Eugenia caryophyllata, as well as cinnamon leaf oil (Cinnamomum zeylanicum) and oil from the clove basil Ocimum gratissimum. While eugenol is often referred to as ...
^Baritaux, O.; Richard, H.; Touche, J.; Derbesy, M.; et al. (1992). "Effects of drying and storage of herbs and spices on the essential oil. Part I. Basil, Ocimum basilicum L.". Flavour and Fragrance Journal. 7 (5): 267–271. doi:10.1002/ffj.2730070507.
^Miele, Mariangela; Dondero, R; Ciarallo, G; Mazzei, M; et al. (2001). "Methyleugenol in Ocimum basilicum L. Cv. 'Genovese Gigante'". Journal of Agricultural and Food Chemistry. 49 (1): 517–521. Bibcode:2001JAFC...49..517M. doi:10.1021/jf000865w. PMID11170620.
^Fandohan, P.; Gnonlonfin, B; Laleye, A; Gbenou, JD; Darboux, R; Moudachirou, M; et al. (2008). "Toxicity and gastric tolerance of essential oils from Cymbopogon citratus, Ocimum gratissimum and Ocimum basilicum in Wistar rats". Food and Chemical Toxicology. 46 (7): 2493–2497. doi:10.1016/j.fct.2008.04.006. PMID18511170.
^"Ocimum tenuiflorum L., Synonyms". The Plant List, Royal Botanic Gardens, Kew and Missouri Botanical Gardens. 23 March 2012. Retrieved 28 November 2019.
^Garibaldi, A.; Minuto, A.; Minuto, G.; Gullino, M. L. (March 2004). "First Report of Downy Mildew on Basil ( Ocimum basilicum ) in Italy". Plant Disease. 88 (3): 312. doi:10.1094/PDIS.2004.88.3.312A. PMID30812374.
^Roberts, P. D.; Raid, R. N.; Harmon, P. F.; Jordan, S. A.; Palmateer, A. J. (February 2009). "First Report of Downy Mildew Caused by a Peronospora sp. on Basil in Florida and the United States". Plant Disease. 93 (2): 199. doi:10.1094/PDIS-93-2-0199B. PMID30764112.
^Wick, R. L.; Brazee, N. J. (March 2009). "First Report of Downy Mildew Caused by a Peronospora Species on Sweet Basil ( Ocimum basilicum ) in Massachusetts". Plant Disease. 93 (3): 318. doi:10.1094/PDIS-93-3-0318B. PMID30764191.
^National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Food and Nutrition Board; Committee to Review the Dietary Reference Intakes for Sodium and Potassium (2019). "Chapter 4: Potassium: Dietary Reference Intakes for Adequacy". In Oria, Maria; Harrison, Meghan; Stallings, Virginia A. (eds.). Dietary Reference Intakes for Sodium and Potassium. The National Academies Collection: Reports funded by National Institutes of Health. Washington, DC: National Academies Press (US). pp. 120–121. doi:10.17226/25353. ISBN978-0-309-48834-1. PMID30844154. Retrieved 5 December 2024.
^ abDube S, Upadhhyay PD, Tripath SC (1989). "Antifungal, physicochemical, and insect-repelling activity of the essential oil of Ocimum basilicum". Canadian Journal of Botany. 67 (7): 2085–2087. Bibcode:1989CaJB...67.2085D. doi:10.1139/b89-264.