A new early-ripening sweet cherry cultivar 'Chunlu'

Abstract:'Chunlu'is an early-ripening and big-fruit sweet cherry cultivar which was bred by'Van'natural crossing. In late May 2002, mature fruit of'Van'natural crossing in the cherry germplasm resources orchard were harvested and cleaned in room. The seeds were extracted and immediately stratified using the mosit sand in the 4 ℃ refrigerator. In late September, the most seeds germinated and were potted in sterile nutrient media in the greenhouse. The seedlings were cultured till transplanted to the nursery in the next spring. In spring 2004, about two hundred seedlings were planted in the cherry breeding nursery of the Zhengzhou Fruit Institute. By the spring of 2007, most cherry seedlings started to fruition. Based on evaluation of main economic characters of fruits over 3 years, the seedling number'15-31'was picked out for its' big fruit, good eating quality, and stable high yield and grafed in the'ZY-1'semi-dwarf cherry rootstock and planted in the Xinzheng and other places for the cultivar evaluation test of the different places in spring 2010. The variety was examined and approved by Henan Forest Tree Variety Evaluation committee on March 2017, and was named as'Chunlu'. The growth vigor of'Chunlu'is high and the tree branch ability middle. The fruits are purple red, kidney-shape, sunken fruit top, short fruit stem and weighing 8.1 g on average. The flesh is purple red and the soluble solids content, total sugar content, titrtable acid content and vitamin C content are 16.4%, 12.48%, 0.64% and 5.58 mg· 100 g-1, respectively. It has pleasant sweet and little sour taste, a rich flavor and fine quality. The tree is highly adaptable, highly flowering high-temperature resistant, very early fruiting and high yield. It has very little malformed fruit, planting on warm temperate zone, than'Hongdeng''Zaodaguo'of the early-ripening cherry cultivars. In Zhengzhou, 'Chunlu'full-bloom period is on March 30 to 31 and is an early blooming cultivar. Fruit ripening period is on May 12-14, fruit development time about 45 days, and is an early-ripenming cultivar. S-genotype is S1 S6, self-unfruitful. It's pollination tree cultivars in Zhengzhou are'Hongdeng''Zaodaguo''Zaohongzhu'and'Longguan'and so on. Orchards spacing in the rows is usually 2-2.5 m and spacing between rows is 4-4.5 m. Training system are usually improvedHuang spindle-shaped, slender spindle-shaped or vertical axis system, et al. In the young tree training and pruning period, branch angle must be timely enlarged and erect shoots must be wiped out for balancing tree potential. Branch-drooping are carried out on September and October. Pruning rule are with the least shoot cutting back pruning possible and promote formation of the bouquet fruit branches. In fullbearing period, branch cutting back and rejuvenation must be carried out after full fruiting for the good tree growth vigor, big fruit and good eating quality.'Chunlu'is an excellent early-ripening sweet cherry cultivar, suitable for planting on warm temperate zone in the Midwest region of China.