Identification of superior walnut (Juglans regia) genotypes in north-eastern Anatolia, Turkey

This research was conducted to identify promising native walnut (Juglans regia) trees growing wild in the Coruh Valley, north-eastern Anatolia, Turkey. The research material consisted of uncultivated walnut trees. From c. 39 000 trees growing in the region, 20 genotypes with superior yield and fruit characteristics were selected and evaluated. These genotypes were resistant to anthracnose and early autumn-late spring frost injuries. The ranges of average fruit characteristics determined for the selected genotypes were: 85-100% terminal fruitfulness; 40-63% lateral fruitfulness; 2.24-3.20 fruits per terminal shoot; 1.45-2.15 fruits per lateral shoot; 9.07-16.01 g nut in shell weight 5.00-7.37 g kernel weight; 45.66-67.14% kernel ratio, and 0.58-1.53 mm shell thickness. The best genotypes were CVWS 13, 46, 138, 150 and 193. These types had thinner shell (0.58 mm, CVWS 13), heavier kernel (7.37 g, CVWS 138), and more lateral fruitfulness (63% CVWS 193 and 60% CVWS 46 and C'VWS 150). Selected walnut genotypes in the Coruh Valley will be used for further breeding purposes in terms of yield capacities, nut characteristics, and cold hardiness.