The population differentiation in seven natural populations of Pinus densiflora was studied based on RAPD markers. Four trees were sampled from each population. Six megagametophytic DNAs per tree were used as template DNAs for genotyping of a seed tree. Two hundred and fifty bands resolved in RAPD with twenty random primers were used to measure the genetic variation of population. The level of genetic diversity was relatively high (A=1.92, P₉₅=92.7, H₀=0.56, H_e=0.40) and the degree of genetic differentiation among populations (F_ST=0.135) was higher compared with those of other pines. The rate gene flow was estimated high ( N_m=1.604). The mean values of genetic distance (0.083) was a very low differentiation and a close genetic relationship in P. densiflora of Korea. Especially, we could find statistically significant relationship between genetic and geographic distances (r= 0.8337, P<0.001). The results obtained suggests that RAPD markers are valuable for the estimation of genetic diversity and for the study of the divergence among population in P. densiflora.

View full abstract

In this paper, the distribution of root systems, the growth and the soil condition were investigated, about 15 Japanese black pines that were planted to the Shonai airport green buffer zone and the nearby windbreak. As a result, the following results were obtained. 1) The relation between the tree height and the root system quantity was straight line with both logarithms. 2) It turned out that phase rate of the object ground had no problem to the root system progress in the soil condition. 3) The growth proportion of the small seedling was higher than the large seedling. From these, we obtained such a conclusion that the small seedling is more advantageous than the large seedling in windbreak development.

View full abstract

The stand structure of Pinus thunbergii Parl. forests were analyzed to provide the information for conservation of coastal forest in eastern part of Kangwon province, Korea. The floristic composition on P. thunbergii Parl. forests were composed of 34 families, 81 genera, 83 species, 11 varieties, 1 forma, totaling 95 taxa. Generally, increasing of the stand age was increased understory vegetation in P. thunbergii Parl. forests. Especially, inland plants were increased. Understory vegetations of P. thunbergii Parl. forests were helpful in many ways. It was stabilized of forest floor and blocked up the movement of sand from the coast.

View full abstract