Abstract: [Objective] This study aimed to investigate the transformation of nutrients in seeds of different Torreya grandis cultivar sand the change characteristics of its after-ripening qualityby comparing the changes in main nutrients of the wild, half cultivated and cultivated T. grandis seeds during after-ripening period under different retting temperatures.[Method] Two retting temperature were applied in this study. The seeds of four T. grandis cultivars (cultivated seeds:T. grandis ‘Zhuyan’ and T. grandis ‘Dingxiang’,T. grandis ‘Dong No.3’; wild seeds:T. grandis Fort. Ex. Lind)were used as experimental materials to determine the changes in the inter seed coat color, starch content, soluble sugar content,soluble protein content, oil content and fatty acid compositions during after-ripening period under the two different retting temperature conditions.[Result] 1) The inter seed coat color of the four T. grandis cultivars changed from red to dark brown after 20 days of treatment with T₂₀. Except for T. grandis Fort. Ex. Lind, the inter seed coat color of the other three T. grandis cultivars was turned to dark brown after 10 days of treatment with T₃₀. 2) Before the retting treatments, the starch content in seeds of T. grandis Fort. Ex. Lind and T. grandis ‘Dingxiang’ was significantly higher than that in the other two cultivars. Compared with before retting treatment, the starch content of three T. grandis cultivars dramatically decreased after 20 days of treatment with T₂₀ and 10 days of treatment with T₃₀ except that the starch content of T. grandis Fort. Ex. Lind seeds did not chang significantly. 3) The soluble protein content in seeds of T. grandis ‘Zhuyan’ and T. grandis ‘Dong No.3’ was significantly higher than that in T. grandis ‘Dingxiang’ and T. grandis Fort. Ex. Lind. In comparison with before retting treatment, the soluble protein of the seeds of three T. grandis cultivars except for T. grandis Fort. Ex. Lind dramatically decreased after treatment with T₂₀ for 20 days, and the soluble protein of three T. grandis cultivars except for T. grandis ‘Zhuyan’ significantly increased after treatment with T₃₀ for 10 days. 4) The oil content and unsaturated fatty acid content in seeds of the four T. grandis cultivars were in the order of T. grandis ‘Dingxiang’ > T. grandis ‘Dong No.3’ > T. grandis ‘Zhuyan’ > T. grandis Fort. Ex. Lind.In comparison with before retting treatment, the oil content and unsaturated fatty acid content in the seeds of four T. grandis cultivars significantly increased after treatment with T₃₀ for 20 days. The oil content and unsaturated fatty acid content were significantly higher in T. grandis ‘Dingxiang’ and T. grandis ‘Dong No.3’ than those in the other two T. grandis cultivars, with T. grandis Fort. Ex. Lind the lowest, after treatment with T₃₀ for 10 days.[Conclusion] It was indicated that the seed quality ofthree cultivated T. grandis was better than that of the wild T. grandis before retting treatment. After retting treatment,the starch content in seeds of the four T. grandis cultivars significantly decreased, while the oil content significantly increased. The increase of the oil content in T. grandis ‘Dong No.3’ was significantly higher than that in the other three T. grandis cultivars after retting treatment, and the increase of the oil content in T. grandis Fort. Ex. Lind was lowest among the four T. grandis cultivars. Although, the response of the four T. grandis cultivars to different retting temperature were different, the higher retting temperature significantly accelerated the after-ripening process of seeds of the four T. grandis cultivars by increasing decomposition of starch and synthesis of proteins and lipid.

Key words: retting temperature, different cultivars, Torreya grandis seed, after-ripening, quality