Kotaro' is a sweet, midseason, medium-sized red apple (Malus pumila Mill.) released in 1998 by the National Institute of Fruit Tree Science (NIFTS), Ministry of Agriculture, Forestry and Fisheries. 'Kotaro' originated from a cross of 'Fuji'×'Hatsuaki' made in 1976. The tree was first selected based on its fruit quality and growth habit in 1986 and was subjected to the local adaptability test, conducted at 20 research sites in 15 prefectures in Japan, as selection number Apple Morioka No.56 from 1991. The cultivar was ultimately selected and released as 'Kotaro' in 1998 and registered as No.9403 under the Plant Variety Protection and Seed Act of Japan on October 18, 2001. At NIFTS in Morioka the 'Kotaro' fruit ripens in late October, 157 days after full bloom, almost the same time as 'Jonagold'. The shape of the fruit is slightly oblong to round with a mean fruit weight of 250 g. The skin color of the fruit at harvest time is almost 100 % red blush and can be dulled by a grayish scarfskin. Small cracking at the stem cavity occasionally occurs. The texture of the flesh is medium, firm, crisp and juicy. The fruit quality is excellent, mean soluble solids content (Brix) in juice is 14.5 % and titratable acidity averages 0.37 g/100 ml as malic acid at harvest. The fruit maintains its firmness and crisp texture for about 80 days in refrigerated storage at 1−4 ℃. The tree is productive without preharvest drop, strong in vigor and spreading in shape, blooming about 4 days after 'Fuji'. Since the S genotype of 'Kotaro' Is S_1 S_3, this cultivar is cross-compatible with major commercial cultivars such as 'Fuji' and 'Tsugaru'. 'Kotaro' is resistant to Alternaria leaf spot.
雑誌名
果樹研究所研究報告
雑誌名(英)
Bulletin of the National Institute of Fruit Tree Science
リンゴ新品種 'こうたろう'
nifs_report_No14p11-23p.pdf
(993.9KB)
各記事の著者欄「