‘Changjo’ Pear

Abstract

‘Changjo’ pear ( Pyrus pyrifolia[Burm. F.] Nakai) was developed from a cross between ‘Tama’ and ‘81-1-27 (‘Danbae’ × ‘Okusankichi’)’ made in 1995 at the National Institute of Horticultural and Herbal Science (NIHHS) of the Rural Development Administration in Korea. It was first selected as ‘95-1-27’ in 2000 for its attractive eating quality, large size and good appearance. After regional adaptability tests at 10 sites for 5 years from 2005 to 2009 as ‘Wonkyo Na-44’, it was named in 2009. It blooms two days later than ‘Niitaka’, a mid-late season leading pear cultivar in Korea. ‘Changjo’ is strong in tree vigor and has an upright-spreading tree habit. It is classified as highly susceptible to pear scab ( Venturia nashicolaTanaka & Yamamoto) having a degree of susceptibility similar to ‘Niitaka’. ‘Changjo’ shows no visual symptoms on any leaves to black necrotic leaf spot caused by apple stem grooving virus. ‘Changjo’ is cross-compatible with major Korean pear cultivars such as ‘Niitaka’, ‘Wonhwang’ and ‘Chuhwangbae’ but not with ‘Whangkeumbae’. The average optimum harvest time of ‘Changjo’ was Oct. 2, 10 days earlier than ‘Niitaka’. The fruit is oblate in shape and yellowish-brown in skin color. Average fruit weight was 789 g and total soluble solids concentration was 13.1 °Brix.