The lumia (''Citrus lumia'' Risso. & Poit., or ''Citrus aurantiifolia'' (Christm. et Panz.) Swingle var. ''lumia'' hort.) is also called the pear lemon (''Citrus'' × ''lumia'' 'pyriformis'), since its shape resembles a

pear Pears are fruits produced and consumed around the world, growing on a tree and harvested in the Northern Hemisphere in late summer into October. The pear tree and shrub are a species of genus ''Pyrus'' , in the family Rosaceae, bearing the p ...

. It is also called French lime and sometimes

sweet lemon Sweet lemon and Sweet lime refer to groups of citrus hybrids that contain low acid pulp and juice. They are hybrids often similar to non-sweet lemons or limes, but with less citron parentage. Sweet limes and lemons are not sharply separated: ...

, even though it is not necessarily sweet. Lumia - Limon à Zucheta Volkamer 1708 138b

In German, the lumia is called Birnenlimone, Patriarch-Citrone, Süsse Limone or Birnenlumie; in French it is called ''Poire du commandeur''. In Chinese it is called Lu mi (露蜜), in Japanese Rumii (ルミー), Vietnamese, Chanh Pháp. The fruit resembles a pear in shape, has a thick peel and is not very juicy. Like a citron, it can grow to a formidable size.

Pomum Adami

There is variety of Lumia called ''Pomme D'Adammo'' or

Adam's apple The Adam's apple or laryngeal prominence is the protrusion in the human neck formed by the angle of the thyroid cartilage surrounding the larynx, typically visible in men, less frequently in women. Structure The topographic structure which is e ...

, and is also included under the name ''Citrus lumia'', according to Risso & Poit, the variety name is ''pomum adami''.

Origin and genetics

The most likely origin for the lumia is the Mediterranean basin. The Lumia is also classified as ''Citrus limon var. lumia'' by Swingle which places it under the taxonomy of

lemon The lemon (''Citrus limon'') is a species of small evergreen trees in the flowering plant family Rutaceae, native to Asia, primarily Northeast India (Assam), Northern Myanmar or China. The tree's ellipsoidal yellow fruit is used for culin ...

, and ''Citrus medica L. var. lumia'', that suggests it is similar to citron. Lumias represent several distinct citrus hybrids. Usually lumias are referred to as a

citron The citron (''Citrus medica''), historically cedrate, is a large fragrant citrus fruit with a thick rind. It is said to resemble a 'huge, rough lemon'. It is one of the original citrus fruits from which all other citrus types developed throu ...

hybrid, because of their size, thick peel and dryness of pulp. Pomo d'Adamo was also described by

Johann Christoph Volkamer Johann Christoph Volkamer (June 7, 1644 – August 26, 1720) was a German merchant, manufacturer and botanist. Life Johann Christoph Volkamer (also: ''Volcamer'', ''Volckamer'', ''Volkammer'', ''Volcameris'') was the son of the physician Johann G ...

as a ''Cedrato'' which is Italian for a citron hybrid, whilst ''Cedro'' refers to a true citron. A recent genomic analysis of several species commonly called "lemons" or "limes" revealed that the various individual lumias have different genetic backgrounds. The 'Hybride Fourny' was found to be an

F1 hybrid An F1 hybrid (also known as filial 1 hybrid) is the first filial generation of offspring of distinctly different parental types. F1 hybrids are used in genetics, and in selective breeding, where the term F1 crossbreed may be used. The term is somet ...

of a citron-

pomelo The pomelo ( ), ''Citrus maxima'', is the largest citrus fruit from the family Rutaceae and the principal ancestor of the grapefruit. It is a natural, non-hybrid, citrus fruit, native to Southeast Asia. Similar in taste to a sweet grapefr ...

cross, while the 'Jaffa lemon' was a more complex cross between the two species, perhaps an

F2 hybrid An F1 hybrid (also known as filial 1 hybrid) is the first filial generation of offspring of distinctly different parental types. F1 hybrids are used in genetics, and in selective breeding, where the term F1 crossbreed may be used. The term is somet ...

. The Pomme d'Adam arose from a citron- micrantha cross, while two other lumias, the ‘Borneo’ and ‘Barum’ lemons, were found to be citron-pomelo-micrantha mixes. In ''The Citrus Industry'', Hodgson wrote of the lumias:

Medicine

According to a Japanese study of 1996, the

albedo Albedo (; ) is the measure of the diffuse reflection of sunlight, solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body ...

extract of the Lumia, was shown to possess the highest inhibitory activity against

cyclooxygenase Cyclooxygenase (COX), officially known as prostaglandin-endoperoxide synthase (PTGS), is an enzyme (specifically, a family of isozymes, ) that is responsible for formation of prostanoids, including thromboxane and prostaglandins such as prosta ...

(IC50 = 24 μg/mL), among other citrus studied. Flavedo extract of ripe Lumia inhibited cyclooxygenase to the same degree as the albedo, more than the pulp extract.

References

MADDI Taklit., Pérez-Román, E., Maiza-Benabdesselam, F. Khettal B., Talon M., Ibanez-Gonzalez V. 2018. New Citrus chloroplast haplotypes revealed by molecular markers using Algerian and Spanish accessions. Genet Resour Crop Evol 65: 2199. https://doi.org/10.1007/s10722-018-0685-7

Sources

Citrus PagesUSDA pageZitrusgarten
{{Taxonbar, from=Q3840598 Lemons Citrus hybrids