Betula costata is a valuable timber and ornamental tree species in northeast China. The seed vigor and growth traits of different half-sib families were systematically compared， and a reference for selecting Betula costata superior family would be provided. Variance analysis and correlation analysis on thousand seed weight， germination rate， germination energy， germination index， sapling height， and base diameter were conducted by using 30 Betula costata half-sib families as materials， and principal component analysis was used to evaluate comprehensively the tested families. The results showed that there was an extremely significant difference in thousand seed weight， germination rate， germination energy， germination index， height， and base diameter among families， respectively. The family heritability of each trait was higher than 0.88. There was an extremely significant positive correlation between different traits. Based on the result of principal component analysis， JL6， JL18， JL22， JL7， JL25， and JL4 were selected as the superior families. The average of the thousand seed weight， germination rate， germination energy， germination index， sapling height， and base diameter of superior families were 19.62%， 15.97%， 15.31%， 26.81%， 32.15%， and 14.49% higher than the total average， respectively. The genetic gains of thousand seed weight， germination rate， germination energy， germination index， sapling height， and base diameter of superior families were 19.46%， 22.67%， 22.79%， 24.07%， 32.07%， and 14.44%， respectively. The mother tree of the above superior families could be preliminarily determined as the preferred mother tree for Betula costata seed collection.

In order to better understand the intraspecific diversity of Saxifraga stolonifera and to explore the possibility of its classification， and to provide reference for the resource protection and innovative utilization of S. stolonifera germplasms， 33 traits from 43 populations of S. stolonifera in China were investigated， and the diversity of phenotypic traits was analyzed by numerical trait variation analysis， qualitative trait genetic diversity analysis， correlation analysis， principal component analysis and cluster analysis. The results showed that： （1）The coefficient of variation of numerical traits was 0.05-0.67， and the diversity index of qualitative traits was 0.19-1.39， and the distribution pattern of maculation and leaf color diversity were high among populations， and the branch number and the ratio of leaf length to width of stolon were the most unstable and the most stable traits， respectively. （2）The coefficient of variation of numerical and derived traits， and the diversity index of quality traits were generally high， and the contribution rates of each principal component were relatively scattered， so it was unsuitable to classify the species into different taxa only by morphological traits. （3）There were differences in the correlation of different personality traits among populations of S. stolonifera， and significant correlations included leaf length and width， length of long lower petal and length of short lower petal， width of long lower petal and width of short lower petal， respectively. （4）Based on the results of morphological clustering， S. stolonifera in China could be divided into three branches， which exhibited certain regional character. ClusterⅠ was composed of eight Southwest populations， two East China populations， and three Northwest populations； ClusterⅡ consisted of four populations from East China， four populations from Central China， four populations from Southwest China， and one population from Northwest China， so Cluster Ⅱ was widely distributed； Cluster Ⅲ consisted of ten Central China populations， six Southwest populations， and one East China population.

Pinus koraiensis is an important tree species used as fruit in northeast China， but due to its long growth cycle， its genetic improvement progress is slow. In order to evaluate and screen the elite P. koraiensis germplasm resources， 36 half-sib families of 20-year-old P. koraiensis from Xiyang forest seed orchard in Jilin Province were used as materials， and the growth traits and wood properties of different families were investigated. The results of variance analysis showed that the differences of each trait among families reached extremely significant level（P<0.01）， and the phenotypic variation coefficients of different investigated traits was 5.89%~45.21%. Except trait straightness（0.46）， the family heritabilities of other traits exceeded 0.5， which all belonged to high heritability. Correlation analysis results showed that the growth traits such as tree height and diameter at breast height had significantly positive correlations（r>0.663）. The contents of hemicellulose， cellulose and holocellulose were significantly correlated with each other among wood traits， while only cellulose and holocellulose were negatively correlated with some growth traits among growth traits and wood properties. The results of principal component analysis showed that 14 traits constituted five principal components， and the cumulative contribution rate was 79.24%. The comprehensive evaluation method was used to evaluate 36 half-sib families， with an admission rate of 10%， three elite families（PK61， PK29 and PK22） were selected according to their growth traits， and the genetic gain of each growth trait ranged from 6.41%- 33.91%. According to wood properties， three elite families（PK16， PK78 and PK10） were preliminarily screened， and the genetic gain of each wood trait ranged from 1.08%-6.72%. Combined with growth and wood properties， three excellent families（PK61， PK29 and PK44） were selected， and the genetic gain of each index ranged from 0.27%-37.28%. The elite families selected in this study can provide the basis for the selection of improved varieties of P. koraiensis.