‘Tsunonozomi’ is a new early-ripening citrus (Citrus sp.) cultivar released by the National Agriculture and Food Research Organization (NARO), Institute of Fruit Tree Science (NIFTS). It originated from a cross between ‘Kiyomi’ (C. unshiu × C. sinensis) and ‘Encore’ (C. nobilis × C. deliciosa) that was performed in 1974 at the Kuchinotsu Branch, Fruit Tree Research Station, Nagasaki, Japan. It was initially selected in 1985. From 2001, when it was designated Kankitsu Kuchinotsu No.37, it was included in the 9th citrus selection national trial, which was conducted at 31 experimental stations in Japan. It was ultimately selected in August 2009 and authorized under the name Mikan Norin No.18 ‘Tsunonozomi’ in March 2012, and subsequently registered as a new cultivar (No.20788) under the Plant Variety Protection and Seed Act of Japan on 24 May, 2011.
The tree has medium vigor with a shape intermediate between upright and spreading. Its degree of alternate bearing is lower than those of ‘Benibae’ and ‘Encore’. There is no fruit puffing. Its resistance to citrus scab caused by Elsinoë fawcettii is higher than that of satsuma mandarin, but its resistance to citrus canker caused by Xanthomonas citri pv. citri is low, similar to that of navel orange. Stem pitting due to citrus tristeza virus is minor. The oblate fruit weighs about 180 g. The rind is orange, 2.4 mm thick on average, and has medium peelability. The fruit surface texture is medium. The fruit ripens in late December in open field cultivation at Minamishimabara, Nagasaki. The soluble solids content (Brix) of juice is moderately high (about 12%), and the acidity decreases to <1.0 g/100 ml in the ripe fruit. The flesh is moderately soft and juicy with a distinctive flavor like that of ‘Encore’. The β-cryptoxanthin content in the flesh is as high (1.82 mg/100 g fresh weight [FW]) as that of satsuma mandarin. The fruit contains a moderate number of seeds.
雑誌名
農研機構研究報告 果樹茶業研究部門
雑誌名(英)
Bulletin of the NARO, Fruit Tree and Tea Science
巻
3
ページ
47 - 60
発行年
2019-03-26
出版者
国立研究開発法人 農業・食品産業技術総合研究機構
National Agriculture and Food Research Organization (NARO)