Delta Valencia, Valencia Delta Seedless, Valencia Seedless (sec. Cottin 2002)
Citrus x aurantium L., pro sp. [Sweet Orange Group] (sensu Mabberley 1997, Bayer et al. 2009); Citrus sinensis (L.) Osbeck (sensu Swingle and Reece 1967; sensu Tanaka sec. Cottin 2002)
Hodgson (1967) noted that: "Delta originated as a dooryard seedling. It is thought to be of Valencia parentage and was found in 1952 by A. Smith, Government Entomologist, at Rustenburg, western Transvaal. It is considered to be promising and has already been planted to some extent."
Crown compact or dense, not weeping. First-year twig surface glabrous; second- or third-year twig surface striate; thorns absent or not persistent; prickles absent or not persistent. Petiole glabrous, length short; wings medium, adjoining the blade. Leaflets one, margin entire (by misinterpretation) or bluntly toothed, shade leaflet blades flat or weakly conduplicate, sun leaflet blades weakly conduplicate. Scent of crushed leaflets sweetly orange-like. Fruit as broad as long or longer than broad; rind yellow (7-10), yellow-orange (11), orange (12), or red-orange (13); rind texture smooth (1-3) or slightly rough (4-5); firmness leathery; navel absent; flesh orange; taste acidic-sweet.
Hodgson (1967) provided the following additional information this year: "This South African variety produces a seedless fruit of high quality that resembles the Valencia but matures somewhat earlier. The tree is vigorous and productive."
Bayer, R.J., D.J. Mabberley, C. Morton, C.H. Miller, I.K. Sharma, B.E. Pfeil, S. Rich, R. Hitchcock, and S. Sykes. 2009. A molecular phylogeny of the orange subfamily (Rutaceae: Aurantioideae) using nine cpDNA sequences. American Journal of Botany 96: 668–685.
Cottin, R. 2002. Citrus of the World: A citrus directory. Version 2.0. France: SRA INRA-CIRAD.
Mabberley, D.J. 1997. A classification for edible Citrus (Rutaceae). Telopea 7: 167–172.
Swingle, W.T. and P.C. Reece. 1967. The botany of Citrus and its wild relatives. In: Reuther, W., H.J. Webber, and L.D. Batchelor (eds.). The Citrus industry. Ed. 2. Vol. I. University of California, Riverside. http://lib.ucr.edu/agnic/webber/Vol1/Chapter3.html.
Search for this cultivar in NCBI Entrez , NCBI Nucleotide, or NCBI Expressed Sequence Tags
Additional information on this cultivar at University of California: Riverside Citrus Variety Collection
Citrus ID Edition 2
October, 2011
idtools.org
