A citrus hybrid is typically a somatic hybrid within the genus citrus, thus, combining two different citrus varieties or species into one, in order to get intermediate traits or the most desirable traits of both parents. This is done by plant breeding which is also called cross pollination. The selection of the progeny of the new hybrid into a new variety is called hybrid speciation. Citrus hybrids are usually marked with the "×" after the word "Citrus", for example Citrus × aurantifolia.
Major citrus hybrids
Minor citrus hybrids (partial list)
- Shikwasa, Hirami lemon - Citrus × depressa
- Kaffir lime - Citrus × hystrix
- Persian lime - Citrus × latifolia
- Rangpur lime - Citrus × limonia
- Sudachi - Citrus sudachi
- Yuzu - Citrus ichangensis × reticulata
- Ponderosa - Citrus limon × medica
- Lumia - Citrus lumia
- Rhobs al-arsa - Citrus limon
- Florentine citron - Citrus limonimedica
- Oroblanco, oro blanco (white gold) or sweetie and Melogold - (Citrus grandis Osbeck × Citrus Paradisi Macf.)
- Pixie mandarin - a cross between King tangor and Dancy mandarin with possible unknown pollen donor
There are also some so called graft hybrids, or more commonly graft-chimaeras, which are not somatically fused but rather combine variegated tissue from scion and rootstock via grafting, a popular example the Bizzaria orange. Those are commonly marked with a plus sign "+" instead with an "x".
Citrofortunella according to the Swingle system, is a hybrid genus, containing intergenetic hybrids between members of the genus citrus and the closely related Fortunella. It is named after its two parent genera. Such hybrids often combine the cold hardiness of the Fortunella, such as the Kumquat, with some edibility properties of the citrus species. Citrofortunellas, which are all hybrids, are marked with the "×" before the word "Citrofortunella", for example × Citrofortunella microcarpa or × Citrofortunella mitis which refer to the same plant.
These plants are hardier and more compact than most citrus plants, often referred to as cold hardy citrus. They produce small acidic fruit and make good ornamental plants. Citrofortunella hybrids include:
- Calamondin — (tangerine crossed with kumquat)
- Citrangequat — (citrange crossed with kumquat)
- Limequat - (Citrofortunella floridana) — (Key lime crossed with kumquat)
- Orangequat - Citrofortunella nippon — (satsuma mandarin crossed with kumquat)
- Procimequat - (Citrofortunella floridana) (limequat crossed with kumquat)
- Sunquat - Citrus limon × japonica — (lemon crossed with kumquat)
- Yuzuquat - Citrus ichangensis × reticulata — (yuzu crossed with kumquat)
Citrocirus also according to the Swingle system, is a hybrid genus, containing intragenetic hybrids between members of the genus citrus and the closely related Poncirus, which includes the trifoliate orange, a cold hardy plant that commonly uses as a citrus rootstock. Citrocirus commonly refer to the citranges which are somatic hybrid between the trifoliate and sweet oranges. They are botanically classified as × Citrocitrus. However a molecular investigation suggested that Fortunella, Citrofortunella, Poncirus and Citrocirus should all be equivocally included in the genus citrus.
- Citrange - Citrus sinensis × Poncirus trifoliata - three cultivars: Troyer, Rusk and Carrizo.
- Citrumelo - Citrus paradisi × Poncirus trifoliata
- "EasyBloom :: Calamondin - x Citrofortunella mitis :: Detailed Plant Information". easybloom.com.
- Gardens World
- Nicolosi et al. (2000), de Araújo et al. (2003)