Abstract: Objective In order to fully develop and utilize the economic value of Pteroceltis tatarinowii and open up new resources of feed production, the nutritional value of P. tatarinowii leaves for feeding was comprehensively analyzed and evaluated, so as to provide data support for P. tatarinowii to be used as woody feed.Method In this study, the nutritional components, antioxidant activities, components and contents of secondary metabolites and amino acids in leaves of 10 clones were determined, and their feeding characteristics were comprehensively evaluated by quality evaluation indexes.Result 1） There were extremely significant differences in different nutritional indicators of leaves among different clones of P. tatarinowii. Crude protein content ranged from 10.15% to 24.36%, with an average of 17.60%, and among the clones 'Fuyuan' (24.36%) and 'WT' (24.33%) had the highest content. Crude fat ranged from 7.98% to 11.45%, with an average of 9.31%. The crude fiber content was low, with an average of 4.08%. The average value of nitrogen-free extract was 49.69%. The difference of neutral detergent fiber among clones was the greatest, ranging from 17.76% to 67.67%, with an average of 45.51%. The difference of acid detergent fiber was small, with an average of 24.07%. The average total phosphorus content and calcium content were 0.1733% and 5.8633%, respectively. Tannin content was far lower than the standard of antifeeding, with an average of 2.9260 g·kg^?1. 2）There were significant differences in the evaluation indicators of feed quality among clones, and 4 out of 10 clones reached the level 1 standard of AFGC, namely 'WT', 'Jinyuyuan', 'Huiguang' and 'Julong'. 3) The antioxidant activity composite index (APC) showed that leaves of 'Daye', 'Julong' and 'Qinglong' had strong antioxidant capacity, while leaves of 'Wuliang', 'Jinyuyuan' and 'Huiguang' had weak antioxidant capacity. 4) There were significant differences in total flavonoids and five flavonoid substances in the leaves among clones, which provided the basis for screening high bioactive substances. The average content of total flavonoids was 9.92 mg·g^?1. The content of chlorogenic acid was the highest (710.96 μg·g^?1), followed by isorhamnetin (27.12 μg·g^?1), catechin (16.53 μg·g^?1) and quercetin (9.09 μg·g^?1). The caffeic acid content was very low, only 1.73 μg·g^?1. 5) A total of 18 kinds of free amino acids and 19 kinds of hydrolyzed amino acids were detected, with an average total amount of 47.87 mg·g^?1 and 108.20 mg·g^?1, respectively. And the total contents of the two kinds of amino acids were significantly different among clones. The contents of isoleucine and leucine were the highest in the two kinds of amino acids. Conclusion The leaves of P. tatarinowii have high content of crude protein, crude fat and calcium, and low content of crude fiber, neutral detergent fiber, acid detergent fiber and tannin, and the comprehensive grade of feeding evaluation index has reached grade 1 standard. It is concluded that P. tatarinowii has the material foundation to develop into an elite woody fodder species. Three elite clones, 'WT', 'Fuyuan' and 'Julong', have been selected preliminarily.

Key words: Pteroceltis tatarinowii, woody forage, nutritional composition, crude protein, amino acid, forage value