Henderson Grapefruit

Accounts differ on Henderson’s origin. Maxwell and Rouse describe a dark-red limb found in 1973 on an “Everhard strain of red grapefruit,” later named Henderson; Saunt also relates Everhard to Fawcett, while Hensz attributes Henderson to a Ruby Red bud sport. C. Everhard’s reported personal account rejects Fawcett and suggests an Everhard Ruby Red strain. Rouse, Wutscher and Youtsey’s 2001 retrospective recounts a 1973 limb report in an Everhard orchard and subsequent propagation and evaluation. US Citrus separately describes Henderson as a Ruby Red limb sport and equates it with Ray Ruby. These accounts do not resolve the competing lineage claims.^{⁠[1]⁠[2]⁠[5]⁠[9]}

Citrus ID’s descriptive profile presents Henderson as having a compact or dense crown and fruit with a slightly rough, leathery rind and red or purplish-tinged flesh. In Sauls’s January–March 1998 Texas comparison, the Henderson equatorial-to-polar diameter ratio increased with fruit size; the reported mean was 1.179.^⁠[3]⁠[4]

Two Adana datasets describe different Henderson material. The 2013 rootstock comparison used trees planted in 1997 at the Citrus Experiment Station; the separate Tuzcu collection paper reports 2011–2012 yields and January 2012 fruit measurements from trees planted in 1984. The latter paper does not state Henderson’s rootstock.^⁠[6]⁠[8]

A 2007 cytogenetic comparison using CMA/DAPI staining and rDNA-FISH reported Henderson among grapefruit accessions with three CMA-positive C-type and five D-type chromosomes, and five 45S rDNA sites. The abstract also reports two 5S rDNA-bearing chromosomes in each accession examined. These marker patterns are not a ploidy determination or proof of Henderson’s parentage.^⁠[7]