First Fruiting Intergeneric Hybrids between Citrus and Citropsis

Abstract

<jats:p>Fruiting hybrids are reported for the first time between the genera <jats:italic>Citrus</jats:italic> L. and <jats:italic>Citropsis</jats:italic> (Engl.) Swing. &amp; M.Kell. Conventional hybridization using the recently described species <jats:italic>Citrus wakonai</jats:italic> P.I.Forst. &amp; M.W.Sm. and <jats:italic>Citropsis gabunensis</jats:italic> (Engl.) Swing. &amp; M.Kell. resulted in high rates of fruit set and seed formation. Although seed were only half normal size, over 90% germinated without the need for embryo rescue techniques. Plant losses were high during the first few months but after six months, the 327 surviving hybrids were potted on. These grew vigorously on their own roots and 35 of them flowered within two years of sowing. Plants flowered continuously but all were pollen-sterile and ovaries abscised shortly after petal fall. However, at 25 months, two newly flowering hybrids began setting fruit. The development, identification, morphology, breeding efficiency, and future implications of this unique germplasm are described.</jats:p>

Molecular Characterization and Stress Tolerance Evaluation of New Allotetraploid Somatic Hybrids Between Carrizo Citrange and Citrus macrophylla W. rootstocks

“…The morphology of somatic hybrids SMC-58 and SMC-73 shows some intermediate characters between the parents. This type of inheritance has also been described in somatic hybrids between Citrus and related genera such as Citropsis, Severinia , and Microcitrus (Smith et al, 2013 ) and also between different Citrus species (Olivares-Fuster, 1998 ). The growth of somatic hybrids when compared with their parents is slower as it has also been described in several citrus allotetraploid somatic hybrids (Grosser et al, 1998 ; Grosser et al, 2012 ).…”

A Review on Role of Wide Hybridization in Crop Improvement

“…Within two years, 35 hybrids flowered continuously, albeit pollensterile, with ovaries abscising shortly after petal fall. Nonetheless, at 25 months, two newly flowering hybrids exhibited fruit set, marking a significant milestone in the development of this unique germplasm with implications for future breeding endeavors (Malcolm W. Smith et al, 2013).…”

“…Additionally, an intervarietal hybridization between varieties Surya and Pusa Dwarf yielded a fruit set rate of 91.7% with 300 viable seeds per fruit. Hybridity of the progenies was verified using ISSR primers, which identified malespecific bands present in progenies but absent in the female parent, providing further evidence of successful hybridization [15][16][17].…”

Microsatellites assisted rapid identification of mandarin hybrids and assessment of their phenotypic variability

“…The true citrus fruits fall under tribe Citreae and subtribe Citrenae of the subfamily Aurantioideae (Swingle and Reece 1967). Within the subtribe, the genera Poncirus and Citropsis bear trifoliate and multifoliate leaves, and show dominant inheritance pattern over unifoliate leaves present in Citrus (Tan et al 2007, Smith et al 2013. However, the differences among the individuals bearing unifoliate leaves are difficult to quantify (Iwata et al 2002).…”