Thompson Grapefruit: Sources

[1]

Marsh Pink grapefruit (opens in a new tab)

University of California, Riverside — Citrus Variety Collection

https://citrusvariety.ucr.edu/crc2010 (opens in a new tab)

Accessed September 18th

[2]

The Origins of Red Pigmented Grapefruits and the Development of New Varieties (opens in a new tab)

J.V. da Graça, E.S. Louzada, and J.W. Sauls · Proceedings of the International Society of Citriculture · 2004

https://www.researchgate.net/publication/263596266_The_Origins_of_Red_Pigmented_Grapefruits_and_the_Development_of_New_Varieties (opens in a new tab)

The paper reports a Marsh bud sport found in Florida in 1913, first named Pink Marsh and released/renamed Thompson Pink in 1924 (p. 369). These are discovery and release/naming milestones, not one date.

Accessed September 27th

[3]

Varieties of grapefruit (opens in a new tab)

CIRAD Market News Observatory · June 2011

https://agritrop.cirad.fr/561087/1/ID561087.pdf (opens in a new tab)

Fruitrop, English Edition no. 190, June 2011, “Close-Up Grapefruit,” pp. 44–46. Printed p. 45 table rates Thompson (Pink Marsh) flesh pigmentation one star on a weak-to-very-strong scale and marks skin pigmentation with a dash; the table is based on James Saunt, Citrus Varieties of the World. This is a secondary categorical comparison, not a measured sample.

Accessed September 29th

[4]

Grapefruit: History, Use, and Breeding (opens in a new tab)

Eliezer S. Louzada and Chandrika Ramadugu · HortTechnology · 2021-05-05

https://doi.org/10.21273/HORTTECH04679-20 (opens in a new tab)

HortTechnology 31(3):243–258 (2021). The review describes Thompson as a Marsh grapefruit bud sport (printed p. 250), and reports limited-region RAPD/SSR similarities among named cultivars (printed p. 252); this does not establish genome-wide identity. Its Ruby Red/Redblush historical dates remain attributed secondary claims, not a replacement for the existing chronology.

Accessed September 29th