SELECTING PLUS TREES OF Castanea mollissima Blume FOR FRUIT EXPLOITATION

Abstract

Castanea mollissima Blume is an edible chestnut species, a specialty of the highlands of Trung Khanh district, Cao Bang province, the tree grows at an altitude of 500 - 2,800 m, most suitable for temperatures from 20 - 21°C. Its growing area generally has average rainfall of 1,700 - 1,900 mm/year and average humidity of 81.9 - 82.3%, which is suitable to be grown in Cao Bang, Bac Kan, Lang Son, Lao Cai (Sa Pa) and Central Highlands provinces. Its nut has a relatively round shape with three dimensions at approximately the same size, one kg of nuts has 100 seeds with an error of 5%. Thirty-one (31) dominant trees of Castanea mollissima Blume have been selected and recognized (Decision 447/QD-SNN dated 07/8/2020), belonging to plantation forest stands in 3 localities: Trung Khanh town, Chi Vien commune, Dinh Minh commune in Trung Khanh district. The recognized plus trees have good growth, high fruit yield and good seed quality, with superiority reached 15 - 258.2% in D_1.3, 16.7 - 70% in H_vn. Moreover, fruit production was stable with fruit yield superiority reached 19.0 - 89.4%, the quality of seeds with nutritional composition reached and exceeded in accordance with Decision No. 496/QD-SHTT dated March 21, 2011 of the National Office of Intellectual Property.