Walnuts are widely distributed in China where they have a long history of cultivation (Gao et al., 2010). Walnut germplasms have been collected and used in various countries, including China, allowing for the discovery of promising genotypes (Chen et al., 2014). Selected or crossbred cultivars have been used to establish orchards since the 1980s in China (Zhao et al., 2010). China has 440,300 hm2 of walnut cultivation area with an annual nut production of 1.6 million metric tons and is ranked first among the walnut-producing countries of the world (Yi, 2017). The Liaoning Institute of Economic Forestry (LIEF) was one of the pioneers of walnut research in China and initiated its walnut breeding program in 1959. International walnut cultivars, including Payne, Franquette, Sunland, and Chico, were introduced into China during 1992–95, but they were unable to survive the cold winter in Liaoning province. ‘Liaoning 1’ was released as a new Persian walnut (Juglans regia L.) cultivar in China on 15 Oct. 2018. This new cultivar was bred and evaluated at LIEF. It has a high yield and excellent nut traits and has thus been widely planted in North China.
Gao, Y., He, F., Wang, H., Zhang, Z., Lei, L. & Guan, R. 2010 Consideration on the development of a walnut industry in China Acta Hort. 361 45 48
Liu, L. & Gao, B.W. 2012 Inoculation test of disease resistance in 17 walnut cultivars or clones (in Chinese) Nonwood Forest Research 30 1 392 394
Pei, D., Zhang, J.P., Zhou, J.R., Huang, F.J., Wang, H., Wang, B.Q. & Yang, W.Z. 2011 The national standard of the People’s Republic of China: Guidelines for the conduct of tests for distinctness, uniformity and stability—Juglans (Juglans L.) (in Chinese). General Administration of Quality Supervision, Inspection and Quarantine of the P.R.C. and Standardization Administration of the P.R.C., Beijing, China
Yi, S.J. 2017 General situation of international walnut production and promotion strategy of walnut industry in China (in Chinese) Journal of Sichuan Forestry Science and Technology 5 105 108
Zhang, J.Y., Mao, X.H. & Xu, P. 2012 Investigation and analysis of winter injury of walnut in Hebei province in 2009 (in Chinese) Hebei Fruits 4 8 10