Khao Thongdi, Thong Di, Thongo Dei, US 145, USDA Thong Dee (sec. Cottin 2002)
Citrus maxima (Burm.) Merr. (sensu Mabberley 1997, Bayer et al. 2009; sensu Tanaka sec. Cottin 2002); Citrus grandis (L.) Osbeck (sensu Swingle and Reece 1967)
Hodgson (1967) noted that: "The description of this Siamese variety was adapted from Groff (1927) and does not correspond with the clone received in California in 1930 from the U.S. Department of Agriculture. Groff states, however, that the original materials sent to the United States consisted of seeds and seedlings. The clone in the California collections produces non-pigmented fruits of indifferent quality. That grown in Florida seems to be different since it is reported to correspond with Groff's description."
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 pubescent, length short, medium, long, or very long; wings narrow or wide, tucking beneath blade. Leaflets one, margin entire or bluntly toothed, shade leaflet blades flat or weakly conduplicate, sun leaflet blades weakly conduplicate. Leaflets not scented when crushed. Fruit as broad as long or longer than broad; rind green-yellow (6), yellow (7-10), or yellow-orange (11); rind texture slightly rough (4-5); firmness leathery; navel absent; flesh yellow; taste acidic-sweet.
Hodgson (1967) provided the following additional notes on the cultivar:
"Fruit medium-large, very broadly obovoid to oblate; apex slightly depressed; seedy. Light yellow at maturity. Rind medium-thin, smooth, and tightly adherent. Under favorable conditions both albedo and flesh are pink-tinged, the latter in streaks. Carpellary membranes thin but tough and readily separable from pulp. Vesicles large; juice plentiful; flavor good. Midseason in maturity.
Tree vigorous and large."
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.
Groff, G.W. 1927. Culture and varieties of Siamese pummelos as related to introductions into other countries. Lingnan Science Journal 5: 187–254.
Hodgson, R.W. 1967. Horticultural varieties of Citrus. In: Reuther, W., H.J. Webber, and L.D. Batchelor (eds.). The Citrus industry, rev. University of California Press. http://lib.ucr.edu/agnic/webber/Vol1/Chapter4.html.
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
Additional information on this cultivar at University of California: Riverside Citrus Variety Collection
Citrus ID Edition 2
October, 2011
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