Abstract
In this paper the characteristics of morphology and growth of 12-year-old F1 hybrid artificially cross pollinated between Pinus thunbergii Parl. as female parent and P. massoniana Lamb. as male parent were investigated for comparing with the progeny trees of open pollinated parents of each species. The plantations were established in Tokuyama Experimental Forest Station, Kyoto University located at Yamaguchi Prefecture in 1970, and the investigation was carried out in 1980.
The results are summarized as follows;
1) The number and position of main and sub resin ducts in the needles of F1 hybrids showed medial characters between the progenies of female and male parent.
2) The position of resin ducts is the genetical characteristic of the species. The main resin ducts in the needles of F1 hybrids mostly situated within the mesophyll, that were the same as female parent progenies (medial). However, the sub resin ducts in F1 hybrids mostly developed the position same as the male parent progenies (external).
3) On the quantitative character of the length and the dry weight per a needle, F1 hybrids showed the medial character between the progenies of parents.
4) The correlations between the position of resin ducts (R. D. I.) and quantitative characters could be found clearly in F1 hybrids and progenies of parents.
5) The progenies of male parent has inherited a sweeping or forking habit. However, such habit has been scarcely observed in F1 hybrids.
6) The height (H) and diameter (D) of F1 hybrid trees showed nearly medial in those of the progenies of parents.
7) Allometric correlations among each organ of F1 hybrid trees are as follows;
VS=0.109 (D²・H)0.856
WS=0.290 VS
WB=0.318 WS1.388
WL=0.395 WS1.216 (W: dry weight)
8) The biomass of F1 hybrid stand 53.9 ton/ha, 22.62 ton/ha, 17.77 ton/ha and 13.51 ton/ha for total organs, stem, branch and leaf respectively.
