| Buddha-finger,Dongtinghuang and Dragon-eye, three important seed-purpose cultivars of Ginkgo biloba L., were selected to study on effects of storage treatments on quality of seed stone as experimental materials. The seed stones of those cultivars, harvested after full ripening , were stored in ice-box with 5 β after treating with radiation of 100Gy60Co and CaCl2-soak for 24h respectively, and were measured on weight of single seed stone , percentage of seed stone floated, respiration intensity(RI), catalase(CAT) activity and contents of water, starch, amylose, amylopectin, soluble sugar, protein, lipid, Chlorophyll and Carotenoid, and were observed on the ultrastructure of shell and endosperm cell at interval of 30days during storage period of 140 days,respectively. The results of above researches after comparing with that of the seed stones stored under room temperature (CK) indicated as follows:(1) The shell of seed stone, cross section of which was consisted of about 25-layer tracheides on which there were a lot of circular and lacerative holes , of the two the latter arranged as spirality , was a thickness of 423.28 u m; tracheid diameter of Buddha-finger, Dongtinghuang and Dragon-eye was 50.056 u m, 57.772 μm and 17.339μm, respectively, percentage of circular and lacerative ones in holes on the surface of tracheid was 83.3%, 97.7%, 6.73% and 16.70%, 2.72%, 93.27%, and the diameter of both was 3.3 μ m, 1.62 μ m,2.40μ m and 9.02 μ m X 3.39μm, 1.38 μ m X 2.56μ m, 14.86 μ m X 2.57 u m on the average.(2) Single stone weight and water content in kernel of above three cultivars began obviously decreasing at the 120th day after storage , the arrangement of which was Dragon-eye > Dongtinghuang > Buddha-finger in order of decreasing rate.(3) The seed stones of those cultivars , were not taken with a mildew until the 120th day after storage, and the embryo growth of which could be inhibited byradiation of 100Gy60Co- γ. and the surface of which treated by 1%CaCl2-soak was attached with a number of calcium grains. The two treatments, made the percentage of seed stone floated be 12.22% and 6.67% lower, and the percentage of water content in kernel be 2.48% and 1.54% higher, and single stone weight be 0.1067g and 0.0891g higher, chlorophyll content in kernel be 1.96mg g-1 and 12.28 mg g-1 higher, than that of CK respectively. Carotenoid content in kernel was 1.59 mg g-1 lower for radiation of 100Gy60Co-γ and 1.05 mg g-1 higher for 1%CaCl2-soak than that of CK respectively.(4) RI of seed stone was rapidly descending after harvest, following that RI began snowly descending and maintaining a lower and stable level. CAT activity was higher at harvest, following that began declining until the 60th day after harvest, then kept a relative stability.(5) In kernels of Buddha-finger, Dongtinghuang and Dragon-eye, the content of starch was 82.06%, 74.95% and 83.88%, the content of amylose was 18.66%, 18.58% and 18.94%, and increased significantly from 30d to 60d after storage, the content of amylopectin was 63.40%, 56.37% and 64.94%, the ratio of the content of amylopectin to that of amylose was 3.40. 3.03 and 3.43. respectively: the content of soluble sugar was 3.80 mg g-1 . 2.87 mg g-1 and 3.41 mg g-1, and was relatively increasing with decreasing of the content of starch and amylopectin during storage.(6) The content of protein and lipid was 7.29%, 8.30%, 8.74% and 3.25%, 3.35%. 2.95%, which increased significantly during storage period of 0~60d and 60~90d, respectively , the content of chlorophyll and carotenoid was 33.28 mg g-1 32.10 mg g-1, 27.04 mg g-1 and 12.05 mg g-1, 10.43 mg g-1, 11.12 mg g-1. which in kernels had no any significant differences among Buddha-finger. Dongtinghuang and Dragon-eye throughout storage period.(7) The endosperm of seed stone, surrounded by aleurone layer, remained most of which to be consisted of thin-walled cell of isodiameter in which the organella had retrogressed and only left starchsome to fill the cell at harvest. Each starchsomeco...
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