Tosu sour orange hybrid

Citrus neo-aurantium

CRC 3607

PI 316538

Photos by David Karp, CVC,  2/11/2008. Photo rights.

Source: Received as seed from the Horticulture Research Station, Okitsu, Japan, via W.P. Bitters, 1966. Open pollinated seedling.

Parentage/origins: Parents unknown. From Izu branch, Shizuoka Prefectural Station.

Rootstocks of accession: Carrizo citrange, C-35 citrange

Season of ripeness at Riverside: January to March

Notes and observations:

3/1987, EMN: A vigorous grower, to be tried as a rootstock. This accession was heat treated in about 1975 for moving out of tristeza quarantine to Lindcove. Subsequent Lindcove nucellar block tree was the bud source. This accession has fruit which appears to be very similar and possibly identical to CRC 3611 (Konejime).

2/26/1988, EMN: This and CRC 3611 still look alike. Many fruit on ground at this date. Small grapefruit sized fruit, yellow to yellow/orange, slightly rough rind, round but most fruits flattened at ends. Rind of medium thickness; fruit seedy. Flesh light orange/yellow, very sour.

2/11/2008 OJB, TS & DK: Light-colored flesh and rind, juicy, very sour; maybe a hybrid of sour orange and citron or mandarin; leaves look more like mandarin or sweet orange. 

Availability: Not commercially available in California.

USDA Germplasm Resources Information Network page for Tosu sour orange hybrid