Variation Analysis of Growth Characters in Young Clones Forest of Pinus massoniana

Pinus massoniana cutting orchard was constructed with 10 tissue culture seedlings as mother plant for the setting up of experimental clonal forest with cutting propagation. The comprehensive evaluation of 1-year-old clone was carried out by character expression level analysis and weighted coefficient method respectively. Results show that the average ground diameter and height and survival rate of clones in P. massoniana were 25.64 mm, 1.32 m and 95.8% respectively, which exceeded the control mean 8.5%, 21.1% and 6.4% respectively. The difference of growth characters between clones and seedlings was very significant (P < 0.01); The ground diameter and height of clones were between 22.16−31.07 mm and 1.12−1.57 m respectively, and the growth difference reached a significant level (P < 0.05), phenotypic variation was abundant between clones; The repeatability of ground diameter and height of clones was 0.84 and 0.92 respectively, and the growth was mainly controlled by heredity. According to the 20% selection rate, MGC-1 and MGC-7 were selected, which average ground diameter and height were 29.80 mm and 1.53 m respectively, the average genetic gain were 13.61% and 14.64% respectively, the average real gain were 16.21% and 15.91% respectively, compared with the control group, the average genetic gain were 21.87% and 37.01% respectively.