Iyo is described in [Hodgson, 1978], p. 531. This accession is probably NOT the same as [PI 539256]. (E.M. Nauer, 04-1988)As a natural consequence of eagerly searching for a Satsuma-like citrus of a good looking and coming to the market a little later, Iyo attracted attention of growers especially in warmer countries where Satsuma cannot be stored satisfactorily until March-April season. It was first discovered in 1883 as a chance seedling tree in Abu-gun, Yamguchi prefecture and was introduced to the Citrus world by several leading horticulturists, finally calling attention of an Iyo nurseryman of Mochida, Matsuyama city, who propagated it and distributed it widely in the same province (Ehime Pref.). It was first called Anado in connection with its native prefecture, but then it became to be called "Iyo". It is a beautiful looking fruit, perhaps more attractive than the Santra of India...or any one of the tangors, but the quality of pulp is nothing better than the Naruto...and Sanbô...being subject to the change of flavor very soon after being picked. (Tanaka, 1961)
The Iyo is believed by Tanaka (1954) to be a natural tangor and was found about 1883 by M. Nakamura in Obu-gun, Yamaguchi Prefecture, Japan. First described as Anado mikan in 1892, it was early introduced into Ehime (formerky Iyo) Prefecture, where it was widely planted and came to be known as Iyo. While attractive in appearance and of good flavor, it loses quality rapidly in storage and on the tree. As a result, it has been little planted in recent years. Currently, its culture is limited largely to the vicinity of the city of Matsuyama. Fruit medium-sized, subglobose to broadly obovoid, apical end shallowly depressed. Rind thick, lightly pitted, tender, and easily separable; deep orange-colkord. Medium seed content (some with pale green cotyledons). Central column broadly open and segments about 10. Flesh orange-colored; tender, very juicy, sweet; flavor rich and pleasant. Midseason in maturity. Tree vigorous. (Hodgson, 1967, p. 531)
Iyokan (C. iyo hort. ex Tanaka) was found in 1886 in a citrus orchard in Yamaguchi Prefecture and was first introduced into Ehime Prefecture, which was formerly called Iyo. It is apparently a tangor. The fruit are medium-large (200 - 300 g), can be easliy peeled,a nd are very fragrant. The segment membrane is not as thick as that of Natsumikan or Hassaku, but it is difficult to eat unless peeled. An early-maturing mutant, Miyauchi Iyokan was found in 1952, and since then plantings have been increasing. The fruits of Miyauchi have a thin skin and are seedless. Their eating quality is mcuh better than that of fruit of the common strain. In 1980, another mutant was found and called Ohtani Iyokan. Ohtani fruit have a smooth, reddish-colored skin and are very attractive. Iyokan is picked before January and is stored until shipment, which occurs from december to April with a peak in February - March. (Kitagawa and Kawada, 1986)
The fruit...is medium to large as compared with other tangors...round in shape...often slightly flattened and has a depressed area at the stem end...a most handsome and attractive fruit with a smooth or very slightly pebbled rind of deep orange colour [sic]...the rind ranges from moderately thick to chick, becoming puffy with age, and is very easily removed. The flavour [sic] is delicately sweet and free from bitterness and notably acidic...15 to 20 seeds per fruit. Most Iyokan are harvested in December then stored until marketed in the February to April period. Thereafter they become dry and rather insipid. Grown mainly in Ehime Prefecture...Iyokans are extremely popular in Japan...(Saunt, 2000)
I have nothing to add at this time except we have the Miyauchi Iyo selection and another standard Iyo selection. (R.R. Krueger, 2021-09-16)
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