对辽东地区无性系评比林中的日本落叶松、长白落叶松及其正反交杂种的光合速率、呼吸速率、全株总叶面积、生长期、生长节律和生长量等指标进行了测定,以比较它们光合生产力的差异。结果表明:与光合速率相比,生长期和全株总叶面积是形成光合生产力差异的主要因素。与长白落叶松相比,日本落叶松的光合速率较低而呼吸速率较高,但因生长期和总叶面积的优势而光合生产力较高。与纯种相比,杂种光合速率和呼吸速率较高,但没有达到差异显著性水平;由于生长期、总叶面积呈偏母系遗传特性,日本落叶松×长白落叶松杂种继承了日本落叶松生长期长和总叶面积大的特点,因而拥有最高的光合生产力,而长白落叶松×日本落叶松杂种的光合生产力较低。综合来看,日本落叶松×长白落叶松杂种的光合生产力最高,长白落叶松的光合生产力最低,日本落叶松和长白落叶松×日本落叶松杂种居中。
In order to compare photosynthetic productivities of Larix kaempferi and L. olgensis, as well as their reciprocal hybrids, traits including photosynthetic and respiration rate, length of growing period, growing rhythm, whole-tree leaf area, and height growth were studied among the four taxa growing in a clone trial located in Dagujia, Liaoning Province, China. The results indicated that compared with photo- synthetic rate, length of growing period and whole-tree leaf area appeared to play determinant roles in forming photosynthetic productivity variation. Although both photosynthetic and respiration rates of Lar- ix kaempferi were inferior to L. olgensis, superiority in length of growing period and whole-tree leaf area endowed it superior photosynthetic productivity. Reciprocal hybrids had the highest photosynthetic and respiration rates compared with the parent species, although not statistically significant. Owing to the ma- ternally inherited pattern of length of growing period and whole-tree leaf area, L. kaempferi X L. olgensis inherited the superiority in these two elements, which helped it possess the greatest photosynthetic pro- ductivity, while L. olgensisXL, kaempferi only showed moderate photosynthetic productivity due to the same reason. In sum, L. kaempferiXL, olgensis possessed the highest photosynthetic productivity, L. olgensis had the lowest photosynthetic productivity, L. olgensis X L. kaempferi and L. kaempferi was between the two taxa.