ニホンナシ栽培品種の変遷と農研機構における品種育成の現状

抄録

The Japanese pear (Pyrus pyrifolia Nakai) is one of the most commercialized fruit trees in Japan and it has been consumed for a long time. The concept of pear cultivars was first developed in the middle of Edo Era (1603-1887). Commercial pear orchards were established in the late Edo Era and over 1000 cultivar name have since been recorded. ‘Taihei’ was the leading cultivar in 1890-1900, followed by ‘Kozo’ in 1900-1910. ‘Chojuro’ became the leading cultivar from the 1910s to the late 1940s due to its high productivity and disease resistance, but ‘Nijisseiki’ replaced it until the late 1980s, as this cultivar had superior flesh texture despite its extreme susceptibility to black spot disease. The systematic breeding program of the Horticultural Research Station [currently National Institute of Fruit Tree and Tea Science (NIFTS), National Agricultural Research Organization (NARO)] began in 1935 and it mainly aimed to improve fruit quality by focusing on flesh texture and black spot disease. As a result, cultivars ‘Kosui’ and ‘Hosui’ were released in 1959 and 1972, respectively. ‘Kosui’ became a leading cultivar in the late 1980s and ‘Hosui’ became second in the beginning of the 1990s. Current breeding at NIFTS uses DNA marker-assisted selection for combining superior fruit quality with traits related to labor and cost reduction, multiple disease resistance, and self-compatibility.