The features of branching and growth studied included height, diameter at breast height (DBH), total number of branches, annual height growth, annual branch elongation in the year of elongating, annual branch number for four consecutive years, diameter of branches of different ages, and diameter of stem where branch-whorl originates. For features of total growth and overall branching, no significant differences were found between families, except for DBH. For annual features, no significant differences were found in annual stem height growth, annual branch elongation in the year of elongation and diameter of branches. In the last four years, differences in number of branches were not significant in the first two years but were significant in the last two year; differences in stem diameter where branch-whorls grow were significant for the four consecutive years. Trend of annual growth and branching features of families can be divided into three types as increasing type, stable type and fluctuating type. Most of families have an increasing type with respect of annual height growth and annual branch elongation, while most families belong to a fluctuating type with annual branch number. The results indicated that in the fifth year after planted in seedling seed orchard, differences between families were mostly insignificant. This result may have two main explanations: one is the growth rhyme in early ages of Masson pine, the other one is the complex paternal components to form the open-pollinated families. Family selection seemed to be not useful based on the result. It is suggested to select some of families in the nursery instead of to use all the families when establishing seedling seed orchards with open-pollinated families from plus-trees.
Eleven microsatellite(SSR)markers were used to evaluate the genetic diversity and paternal parents of a seed orchard for Pinus massoniana planted at Wuyi Forest Farm,Fujian Province.The seed orchard contains 286 open_pollinated progenies derived from 129 candidate paternal clones and three maternal trees.Both the parental and progeny populations displayed high genetic diversity(h),with the estimated h values of 0.543 8 and 0.455 6,respectively.Paternal clones contributed differently to the progeny;only 5.3%～15.8% clones contributed 27.08%～48.96% pollen.More strikingly,one paternal clone contributed 10% and 17% pollen,respectively,to two maternal trees.It was found that the mating compatibility of a clone was not related to its origin.There was no significant influence of the physical location of a clone on the amount of paternal constituent and genetic diversity.The rate of contamination by pollen outside the seed orchard was as high as 9.44%.No selfing progeny was observed,suggesting that selfing depression will not be an issue in the seed orchard of P.massoniana.
