Breeding report of a new Torreya grandis cultivar ‘Pan’ an Changfei’

Abstract:‘Pan’an Changfei’is a new cultivar selected from old trees of Torreya grandis in Pan’ancounty of Zhejiang province. The variation maternal plant was an old grafting tree, and the progenieswere cultivated through asexual reproduction. It is a bud mutation variety. It was initially selected in2005 for its thin and long seed. The variation maternal plant was discovered in Dapan town, Pan’ancounty. Through grafting, planting of‘Pan’an Changfei’was expanded in 2010. And the DUS testingfinished in 2017. Finally, the new variety of Torreya grandis was registered in 2018 after several years’selection. This cultivar is a tall tree, attaining a height of 11 m. The tree is vigorous with circular orsemicircular crown and open tree gesture. Leaves are linear lanceolate, 0.8-2.2 cm long, and 0.2-0.3 cmwide. The upper epidermis of its leaf is dark green and the lower epidermis is light green. It is a dioecismplant, the floral bud is a mixed bud, and ovules are attached to the middle part of bearing branch.The seed is drupaceous and encircled by arillus. The shape of its seed (nut, kernel) is thin and extralong, and is different from the shape of Torreya grandis‘Xifei’. The average single mass of fresh seedis 6.8 g, and the average vertical diameter and horizontal diameter of seed is 3.62 cm and 1.73 cm, re- spectively. The average index of seed shape is 2.10, and the average peel thickness is 0.33 cm. The averageratio of fresh nut and seed is 37.13%, while the average ratio of dry nut and seed is 70.24%. Themean fruit weight of fresh nut is 2.5 g. The mean vertical diameter and horizontal diameter of nut is3.45 cm and 1.18 cm, respectively. The mean index of nut shape is 2.95, and the mean shell thickness is0.08 cm. The mean ratio of dry kernel and nut is 69.08%. The mean weight of dry kernel is 1.1 g, andthe oil content of dry kernel is 50.4%. The content of soluble sugar and protein is 2.87% and 14.0%, respectively.The seed quality is excellent and the product performance is good. The anthesis period ismid April, the mature period is early September of next year, and the seed development period is 17months in Pan’an, Zhejiang province. Its seedlings and young trees need dank environments and fearhigh temperature, drought and intense sunlight, but the mature trees are resistant to cold, heat anddrought. Through progeny testing, the results showed that its performance was consistent with maternalplant in the shape of seed and kernel quality. It is a stable variation. It is suitable for cultivation in Torreyagrandis growing areas of Zhejiang province. Its cultivation requirements are the same as Torreyagrandis‘Xifei’. It should choose subacidity to neutral sandy soil which is flat and has ability of moistureand fertilizer retention and the altitude should be less than 800 m. Virus-free seedlings were plantedwith row spacing of 4 m × (4-5) m and 450-670 plants per hectare, and the configuration of pollinizer is5%. For young trees, the tending managements should focus on shading at 5-9 months, trees management,applying fertilizers. For adult trees, the tending managements should put emphasis on fertilizing,weeding, loosening the soil, increasing the set of fruit, pruning and training properly, strengthening thecomprehensive control of pests and diseases.