Seed Traits Variability And Selection For Nut Production Clones Of Ginkgo Biloba L.

27 and 52 clones of Ginkgo biloba in Tancheng gene pool and Pizhou germplasms were studied. The photosynthesis indices, the weight and morphological indices of seed and nut, the chemical compositions of nut were analyzed, based on these analyses, the variability and the correlativity between clones were determined. These indices were evaluated and the superior clones for nut production were chosen. The main results were described as follows:(1)The variability coefficient of photosynthesis indices between 79 clones were listed in descending order as Tr(18.191%), Gs(17.42%), WUE(15.599%), Pn(12.577%), Ci(7.820%). Analyses on the variability of weight and morphological indices of seed and nut in two experimental sites showed that single seed weight(20.922%) and single nut weight(19.106%), percentage of nut to seed(11.553%) were high while the variability of morphological indices such as length of nut(9.568%), width of nut(8.455%) and thickness of nut(7.340%)were low. Analyses on the variability of the chemical composition of nut in descending order were listed as the content variability of Cu(51.274%), that of Ca(52.140%), that of total flavonoids(48.473%), that of Zn(35.526%), that of K(19.040%), that of fat(17.2%) and that of starch(9.802%) were lower.(2)There were 528 pairs of relevant values, of which 110 correlation coefficients were very significant or significant. There were 67 pairs of relevant values showing positive correlation, while 43 pairs of relevant values showing negative correlation.(3)Based on the improved analytic hierarchy process, the weight and morphological indices of seed and nut, the chemical compositions of nut and nut yield of single clone were evaluated, the clones with higher evaluation index listed in descending order as 71~#,1~#,62~#,35~#,52~#,42~#,15~#,50~#. These eight clones were showed with higher weight of seed and nut, content of chemical compositions among 79 clones.15~#, 19~# and 59~# clones were chosen as medical using clones for nut production, the average content of total flavonoids and total lactones were 1.692 and 1.423 times of average content of 79 clones respectively. 1~#, 15~# and 71~# clones were chosen as high single nut weight clones for nut production, the average single nut weight of these clones was 1.460 times of average single nut weight of 79 clones. 9~#, 12~#, 34~#, 39~#, 49~#, 54~#, 56~# and 60~# clones were chosen as for high nut yield clones, the average nut yield of single clone of these clones were 2.440 times of average yield of 79 clones.