Breeding report of a new pitaya cultivar Yuehong No. 5

Abstract: Yuehong No. 5 is a new pitaya cultivar selected from the crossing progenies of Dahong × Common white flesh. Dahong is a self-compatible and productive variety with red flesh and medium quality. Its fruits are usually small and the scales are easily dry in high temperature season. Common white flesh is a self-compatible and productive variety with white flesh and grass taste. About 3000 hy-brid seeds were sowed in July, 2013. About 1000 healthy seedlings were chosen and transplanted in nursery in August. The scions of the seedlings were grafted on white- fleshed variety in the breeding nursery in Oct, and a total of 350 grafted seedlings survived and were planted in the field. Eight excel-lent strains were preliminarily selected in Oct 2014. The strain S8-301 was characterized by self-com-patibility, white pulp, high sweetness, and pleasant taste without grass taste. Even more impressively, few thorns were seen on the stem of the strain, which would make planting safer and easier. The strain had stable yield and quality fruits. The regional field trials initiated in Guangzhou, Dongguan, Jiang-meng and other nearby regions in Guangdong Province in 2015. The results of five years trials showed that the cultivar had stable botanical and biological traits, wide adaptability, high disease resistance and excellent fruit quality. It was registered as a non-major crop cultivar by the Crop Variety Approval Com-mittee of Guangdong Province and was named as Yuehong No. 5 in August, 2021. The bracts were linked to the peel closely or slightly stretched out. The length and thickness of bracts were moderate. The number of bracts per fruit was 16-22. The apex of bract was green. The fruit was oval and medium size, with average single fruit weight of 310.0 g, average longitudinal diameter of 10.5 cm, average hori-zontal diameter of 7.6 cm. After full ripening, the peel is pink and the flesh is white, compact, crispy, juicy and sweet, with soluble solids content of 14.14%, total sugar content of 12.54%, reducing sugar content of 10.12% and titratable acid content of 0.172%. It takes 16-18 days from bud germination to flowering, and blooms in several batches from late April to late Oct. The fruit development period is 28- 40 d. The first and last batch of fruit ripened in the ends of May and November. The first batch of flow-er buds appears 8-10 d earlier than the parents. The fruit setting rate of natural pollination was 92%. The cultivar showed strong resistance to pitaya canker disease, while the parents were easily infected. The yield was high and stable. It should be cultivated in the soil with pH 5.5-7.5, good soil drainage, sufficient sunshine and convenient transportation.