Ahmer, Sunrise (sec. Cottin 2002)
Citrus x aurantium L., pro sp. [Grapefruit Group] (sensu Mabberley 1997, Bayer et al. 2009); Citrus paradisi Macfad. (sensu Swingle and Reece 1967; sensu Tanaka sec. Cottin 2002)
The Chiefland Budwood Facility (2010) provided the following notes on the cultivar (clone DPI-60): "Originated from Texas A&I from irradiated seed of Hudson grapefruit variety 1970....Released in 1977."
Crown compact or dense, not weeping. First-year twig surface pubescent; second- or third-year twig surface striate; thorns absent or not persistent; prickles absent or not persistent. Petiole glabrous, length short, medium or long; wings medium or wide, tucking beneath blade. Leaflets one, margin bluntly toothed, shade leaflet blades flat or weakly conduplicate, sun leaflet blades weakly or strongly conduplicate. Scent of crushed leaflets sweetly orange-like. Fruit as broad as long or longer than broad; rind green-yellow (6), yellow (7-10), yellow-orange (11), orange (12), or red-orange (13); rind texture slightly rough (4-5); firmness leathery; navel absent; flesh red/purplish-tinged; taste grapefruit-like.
The Chiefland Budwood Facility (2010) provided the following additional notes on the cultivar (clone DPI-60): "The principal advantages are the deep red internal color and exterior red blush. Leaves blotchy, chlorotic areas. Problems: Sensitive to some herbicides, footrot, and cold. Fruit quality is not as good as Ruby Red with slightly smaller fruit size."
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.
Chiefland Budwood Facility. 2010. 2010 Annual report July 1, 2009 - June 30, 2010. Bureau of Citrus Budwood Registration, Florida Department of Agriculture & Consumer Services, Winter Haven.
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