Capsicum rhomboideum
{{Short description|Species of flowering plant}}
{{speciesbox
|image = Capsicum rhomboideum at flowering.jpg
|image_caption =Capsicum rhomboideum at flowering featuring yellow flowers.
|genus = Capsicum
|species = rhomboideum
|authority = (Dunal) Kuntze
|synonyms = * Capsicum ciliatum {{au|(Kunth) Kuntze}}
- Witheringia ciliata {{au|Kunth}}
|synonyms_ref = {{cite web|url=http://fatalii.net/Chile_Peppers/Species/C_rhomboideum|title=Fatalii's Empire - C. Rhomboideum }}
}}
Capsicum rhomboideum is a perennial member of the genus Capsicum with 2n=2x=26, and is considered a distant wild relative of the chili pepper. Its fruit do not have any pungency, and are a 0 on the Scoville Heat Unit scale.{{Cite journal|title = DNA Barcoding in a Crop Genebank: The Capsicum annuum Species Complex|last = Jarret|first = Robert L.|date = August 22, 2008|journal = The Open Biology Journal|volume = 1|issue = 1|pages = 35–42|doi = 10.2174/1874196700801010035|doi-access = free}}{{Cite book|title = Peppers: Botany, Production and Uses|url = https://books.google.com/books?id=aR6LUhTL4X0C|publisher = CABI|date = 2012-01-01|isbn = 9781845937843|language = en|first = V. M.|last = Russo}} It gets its name from the rhomboidal to elliptical shape of its leaves.{{Cite journal|title = Lectotypifications, synonymy, and a new name in Capsicum (Solanoideae, Solanaceae)|journal = PhytoKeys|date = 2011-02-11|issn = 1314-2011|pmc = 3174431|pmid = 22171173|pages = 23–38|issue = 2|doi = 10.3897/PhytoKeys.2.730|first = Gloria E.|last = Barboza | doi-access=free }} It is native to Mexico, Central America, and Andean region of South America.{{Cite journal|title = FISH and AgNor mapping of the 45S and 5S rRNA genes in wild and cultivated species of Capsicum (Solananceae)|journal = Genome|date = 2015-11-18|issn = 0831-2796|pages = 95–113|volume = 59|issue = 2|doi = 10.1139/gen-2015-0099|pmid = 26853884|first1 = Marisel A.|last1 = Scaldaferro|first2 = M. Victoria Romero|last2 = da Cruz|first3 = Nicolás M.|last3 = Cecchini|first4 = Eduardo A.|last4 = Moscone|url = https://zenodo.org/record/909110|hdl = 11336/113316|hdl-access = free}}{{Cite journal|url = http://pubag.nal.usda.gov/pubag/downloadPDF.xhtml?id=17481&content=PDF|title = The Evolution of Chili Peppers (Capsicum - Solanaceae): a Cytogenetic Perspective|last = Moscone|first = Eduardo|date = 2007|journal = Acta Hort|issue = 745|pages = 137–170|doi = 10.17660/ActaHortic.2007.745.5|editor-last = Spooner|access-date = 2016-02-20|archive-date = 2017-03-05|archive-url = https://web.archive.org/web/20170305142946/https://pubag.nal.usda.gov/pubag/downloadPDF.xhtml?id=17481&content=PDF|url-status = dead|url-access = subscription}}
Plant description
Capsicum rhomboideum is typically a perennial shrub. It is densely covered in trichomes, making it pubescent. It is best identified by its rhomboidal to elliptically-shaped leaves. The flowers have a five-toothed calyx and yellow bell-shaped corolla.{{Cite journal|title = Three New Species of Capsicum (Solanaceae) and a Key to the Wild Species from Brazil|journal = Systematic Botany|pages = 863–871|volume = 30|issue = 4|doi = 10.1600/036364405775097905|first1 = Gloria E.|last1 = Barboza|first2 = Luciano De Bem|last2 = Bianchetti|year = 2005|s2cid = 85972658|hdl = 11336/38870|hdl-access = free}} The pollen grains are extremely small, 15 μm.{{Cite journal|title = Pollen phenotyping and performance in rocoto chili (Capsicum pubescens Ruiz et Pav., Solanaceae)|journal = Grana|date = 2015-01-02|issn = 0017-3134|pages = 37–44|volume = 54|issue = 1|doi = 10.1080/00173134.2014.985606|first1 = María Laura|last1 = Bo|first2 = Carolina Carrizo|last2 = García|hdl = 11336/12419|s2cid = 85079130|hdl-access = free}} Mature fruit of C. rhomboideum are pea-shaped and sized, bright red to black when fresh, and they darken as they dry. They typically bear 2-6 seed per fruit. The seeds are brown.
Genome
The genome of C. rhomboideum is smaller than that of C. annuum. In the specific differentiation, C. rhomboideum likely underwent genome size reduction. Approximately 5% of the genome is heterochromatic. The typical Capsicum has 2n=24, and since 2n=26 in C. rhomboideum , causing it to be reclassified from Capsicum ciliatum in 2001.