Abstract:

The cone and seed characters of Pinus Massoniana were investigated in a clonal seed orchard for two successive years(1998 and 1999).The results showed that significant genetic variation existed among clones,while variation within clone had not come up to remarkable standard.Broad sense herit ability of cone and seed characters in P.massoniana were influenced by genetic factors,most of them were at over middle level.There was a extremely significant difference in the correlation coefficients among the characters of cone and seeds,and the correlation coefficients of the same character in different years were at the extremely significant level,which indicated that the clones were quite stable from year to year in cone and seed quality and size.At last,the comprehensive evaluation was estimated in 140 clones by main index of reproductive capacity.The genetic gain of cone yield of a single tree,the seed numble of a single cone,and full seed percentage,and reselection of clones were discussed under different selection intensities.

Key words: Pinus massoniana, Clonal seed orchard, Cone and cone characteristics, Reproductive capacity, Genetic parameter