Breeding of a new blueberry cultivar Chenyan

Abstract：Chenyan, a new blueberry cultivar, was bred from the natural hybrid seedlings of Brigitta. The collected seeds were sown in the spring of 2011 and 231 seedlings were planted in the spring of 2012. Those bushes ripened in early July, 2015, from which a superior offspring was selected and numbered SMN- 473, which was later named Chenyan. After a series of tasting and identification, it was found that the cultivar had excellent characteristics, such as large fruit grains, oblate shape, light blue color, medium fruit powder and uniform texture, sweet and crisp fruit, good flavor with fragrance, proper firmness and good yield, and it was suitable for fresh market. From July 2017 to July 2018, the comprehensive evaluation on the traits of excellent strains and clones was completed. The results indicated that the plant morphology, fruit quality, fruit yield, flowering and fruiting characteristics and other comprehensive traits were quite consistent, and the specific traits were also stable. In May, 2022, it obtained the new variety certificate issued by the State Forestry and Grassland Administration, and was formally named Chenyan. This cultivar belongs to Northern High-bush Blueberry, the bush gesture is semi-open and vigor is medium. The leaves are long elliptic and dark green in color, and the edge of the leaves is serrated, with an average leaf area of 8.37 cm2 , leaf shape index of 1.77 and early germination of leaf bud. The average length of new bearing branches is 4 cm, and the number of fruits per branch is 9. The cluster of fruit is dense. The fruit shape is oblate, and the color is medium blue (102-B), the scar is small and wet, fruit firmness (3.46 kg·cm^-2 ) is high, and the average single fruit size is 1.47 cm × 1.93 cm. Themaximum fruit weight is 3.32 g, the average fruit weight is 2.6 g, the soluble solids content is 12.11%, and the acidity is medium. Under natural conditions, the initial ripening period is about in the first ten days of July, and it is a medium-early maturing cultivar. Northern areas of the Yangtze River is suitable for planting this cultivar. The cultivar requires loose, deep and fertile soil, and well drained and wet but not water logging land. The soil texture should be loam or sandy loam with pH value of 4.0-5.5 and the organic matter content of more than 10.0% is better. The chilling requirement of the planting area should reach more than 600 h. The selected land must be ploughed and leveled, and the ploughing depth is about 20-30 cm. As for planting, we usually select 2 or 3-year-old potted seedlings or bare-rooted seedlings with a plant height of more than 40 cm and a diameter of more than 0.4 cm at the base of the main stem to establish an orchard. With regard to the management of soil, fertilizer and water, the whole orchard is required to be covered with straw, sawdust or pine needles on the ground. The thickness of the mulch is more than 10 cm, as it can moisturize the soil and upgrade soil organic matter content, and meanwhile, the physical and chemical properties of the soil are improved. Before planting seedlings, it is required to apply decomposed organic manure. At flowering stage, bees can be applied to increase pollination rate and fruit set, and a special attention should be paid to water supply during fruit swell stage.