Open pollination progeny test and excellent family selection of Liquidambar f ormosana
The growth traits of 11 year old Liquidambar formosana plus tree progeny were analyzed, the results were as followes. Differences of tree height, DBH, volume and crown volume among families were very significant, the additive variation coefficient of each trait was above 25%. The maximal value of tree height was 13. 0 m,the minimum is only 1. 30m; the maximal value of DBH was 12. 2 cm, the minimum is only 1. 0cm; the maximal value of volume was 0. 074 85 m3, the minimum is only 0. 000 15 m3, and more than half families were better than the local commodity species. The family heritability of tree height, DBH and volume were were above 0. 7; the correlations a-mong tree height, DBH, volume and crown volume were very plus close, the correlation coefficients were above 0. 4,and the correlation coefficients of height, DBH and volume were above 0. 8. According to the comprehensive comparison, 19 superior families with good performance in growth were selected from 54 open pollinated families tested, the average of height, DBH and volume was 7. 67 m,6. 38 cm and 0. 015 7 m3 respectively, the average genetic gain was 8. 75%, 9. 87% and 24. 97% respectively, the average real gains of 10. 44%, 12. 56% and 31. 93% respectively; the best family average of tree height, diameter and volume of the average of 7. 72 m, 6. 9 cm and 0.0189 m3, the genetic gain was 9.4%, 17.6%, 46.0%, the real gain was 11. 2%, 22.4% and 58.8%. The selected family should be saved to the gene bank or directly applied to production.