Breading of a new cold-resistant and late-ripening nectarine cultivar Daqingpiliguangtao

Daqingpiliguangtao is a new cold-resistant and late-ripening nectarine variety, a natural seedling from Qingpi nectarine in Jiuquan City, and selected over several years. It was officially named Daqingpiliguangtao after being reviewed and approved by the Gansu Provincial Forest Tree Variety Approval Committee in March 2024. The original maternal plant of Daqingpi was the green- skinned Prunus persica (L.) Batsch. The cultivar Qingpiliguangtao was discovered in 1998 at Fuqiang Village, Huangqu Township, Dunhuang City (Accession No. D008), with average fruit weight of 80 g. Through seedling propagation from 1999 to 2002 and subsequent selection of elite seedlings from 2003 to 2006, a superior genotype was identified at Dujiadun Village, Qili Town, Dunhuang City. Since 2007, scion grafts collected from this selected mother plant have been vegetatively propagated for regional adaptation trials. Daqingpiliguangtao exhibits moderate tree vigor with an open canopy architecture. Eightyear-old trees trained in the natural open-center system attain the heights of 2-3 m with crown spread reaching 3-4 m. One-year-old shoots display glossy purplish- red coloration on sun-exposed surfaces. The branching capacity is moderate, with approximately 90% of fruiting shoots bearing compound buds and 10% single buds, all densely pubescent. Leaves measure 12- 13 cm in length and 3- 3.5 cm in width, exhibiting emerald- green coloration and thickened lamina. Venation patterns show yellowishgreen primary veins extending straight to leaf margins with minimal reticulation. Petioles (0.6-0.8 cm in length) bear 2-3 reniform glands with grayish-brown pigmentation. Leaf margins present obtuse-ser-rated dentations with blunt apices. The campanulate flowers feature pink corollas composed of five obovate petals. The androecium consists of over 18 stamens, while the pistil displays pale yellow coloration, maintaining equal or slightly superior height relative to stamens. The fruit is spherical, with an average single fruit weight of 124.5 g and a maximum of 188.0 g. The fruit surface is entirely smooth and green, occasionally adorned with purple stripes. The stone is easily separable, and the flesh is creamy white, becoming soft and juicy when fully ripe. The flesh is delicate with minimal fiber, offering a delightful balance of sweet and sour flavors. The soluble solids contents range from 11.80% to 12.40%. It exhibits a high self-fertility rate and ripens in late September in Jiuquan City, with a fruit development period of approximately 150 days. After years of cultivation and observation, this variety has exhibited tolerance to drought, cold, and pests and diseases, coupled with high yields. It is ideally suited for cultivation in arid and semi-arid peach-producing regions in the north, such as the Hexi Corridor. Proper orchard selection and planning should be conducted before planting, preferably in a north-south orientation. For planting, seedlings with root lengths exceeding 30 cm, at least four lateral roots, stem diameters of at least 0.8 cm, heights of at least 100 cm, at least six full buds within the training zone, wellhealed grafts, and free from damage and pests and diseases should be selected. The method of shallow planting in large holes should be adopted, with planting holes of 60 cm×60 cm. The optimal tree shapes include the three-leader open center, natural open center, Y-shape, and independent trunk system. Pruning should be conducted in winter and summer to ensure uniform fruiting each year. Irrigation and fertilization should be managed according to the water and nutrient requirements in the peach growth cycle. Integrated pest management strategies, including agricultural practices, physical controls, biological controls, and chemical control measures, should be employed.