Subtropical Plant Science, 53: 16-18.2001 16 ‘Miho’ and ‘Seto’—New High Quality Satsumas For Texas Larry A. Stein 1 and Jerry M. Parsons 2 1 Texas A& M University Research and Extension Center, P.O. Box 1849, Uvalde, TX 78802-1849 2 Texas Cooperative Extension, 3355 Cherry Ridge, Suite 212, San Antonio, TX 78230 INTRODUCTION AND HISTORY Satsuma mandarins (Citrus unshiu Marc.) are among the most cold hardy citrus varieties that have sufficient fruit quality for potential commercial marketing as well as for homeowners outside the typical citrus belt in the Lower Rio Grande Valley (Mortensen, 1983). Satsuma mandarin was first reported in Japan more than 700 years ago where it is now the major cultivar grown, but more than likely it originated in China (Ferguson, 1996). The first recorded introduction into the United States was in Florida by George R. Hall in 1876 (Ferguson, 1996). The name “satsuma” is credited to the wife of the United States minister to Japan, General Van Valkenberg, who sent trees home in 1878 from Satsuma where it was believed to have originated (Ferguson, 1996). While this fruit is grown primarily for fresh consumption, a portion of the crop is canned as fruit segments or juice in Japan, China and Spain. In these countries, deeply colored juice is blended with orange juice to improve color or sold as single-strength tangerine juice. Fresh fruit is also imported into Canada and non-citrus producing areas of the U.S., where it is the earliest seasonal citrus crop to reach the market (Ferguson, 1996). Approximately one million ‘Owari’ satsuma trees were imported from Japan (1908-1911) and planted throughout the lower Gulf Coast states from the northern Florida Gulf coast to Texas, where an extensive tangerine industry developed (Ferguson, 1996). The earliest citrus in Texas was from seed planted in dooryards by the early settlers (Mortensen, 1983). The coastal area near Houston and Beaumont had a citrus “boom” until February, 1911, when the temperature dropped to -13.3ºC at Alvin. Most growers were lucky to save 10 percent of their trees. This was followed by the 1915 hurricane, so the Texas Orchard Development Company moved its operations to the Lower Rio Grande Valley where a railroad had recently been built. The Texas Experiment Station at Beeville was also growing citrus and reported success with satsumas in a publication in 1909. There were an estimated 800 acres of trees in the Winter Garden (Uvalde- Crystal City-Pearsall) in 1945 (Mortensen, 1983). Satsumas have been observed to tolerate temperatures of -9.9 to -11.0ºC without injury if trees are totally dormant and the temperature doesn’t remain there more than 3 hours (Ferris and Richardson, 1923; Mortensen, 1983; Ferguson, 1996). Because of their low total heat requirement, some cultivars ripen earlier than most other citrus. Hence, the satsuma is ideally adapted to regions with winters too cold for other citrus fruit but with growing seasons warm enough to produce fruit of early maturity and good quality. The range of climatic adaption for commercial culture is therefore narrow and restricted to the higher elevations and colder areas of the sub-tropical zones. Although these areas are subject to severe freezes, current cold protection methods, using in-tree micro- sprayers, can protect trees to a height of approximately four feet. This cold protection strategy may be the key to at least partial revitalization of satsuma planting in these areas (Ferguson, 1996). ‘Miho’ and ‘Seto’ Cultivars. Early-maturing, high- quality, cold-tolerant varieties of satsumas were obtained from Japan for evaluation in Texas. ‘Miho’ and ‘Seto’ are two such varieties developed from seed produced by controlled pollination of ‘Miyagawa’ satsuma (similar to ‘Okitsu’, which was introduced to Spain in 1983, starting its commercial spread in 1987, (IVIA, 1983)). ‘Miho’ and ‘Seto’ were obtained as seed from the Fruit Tree Research Station - Okitsu Branch, Obitsu, Shimizu, Shizuoka 424-02 Japan in November, 1984, and subsequently planted in containers in Table 1. Characteristics of satsuma varieties in Texas (Sauls, 1998). Peel Variety Fruit size Seed Peel color Flesh color adherence Season Owari Medium 0-4 Red-orange Orange Loose Nov-Dec Armstrong Early Large 0-4 Red-orange Lt-orange Loose Oct-Nov Kimbrough Medium 0-4 Red-orange Orange Loose Nov-Dec Obawase Large 0-4 Red-orange Orange Loose Oct-Nov Okitsu Medium 0-4 Red-orange Orange Loose Nov-Dec Miho Large 0-2 Red-orange Orange Loose Oct-Nov Seto Large 0-2 Red-orange Orange Loose Oct-Nov Mr. Mac Medium 0-4 Red-orange Orange Loose Nov-Dec Changsha tangerine Medium 20-30 Orange Orange Loose Oct-Jan