Total Dry Weight Increment in Relation to Net Assimilation Rate, Total Amount of Leaf Area, Leaf Duration, and Leaf Longevity in Some Poplar Clones

1990

S. 1-10

7 Abb., 1 Tab., 21 Lit. Ang.

Unselbständiges Werk

200087901

Effects of net assimilation rate and total amount of leaf area and leaf duration, leaf longevity on total dry weight increment among seven poplar clones: OP20 (P. charkowensisxP. caudina), OP29 (P. charkowensisxP. trichocarpa), OP206 (P. deltoidesxP. trichocarpa). OP226 (P. deltoides virgianaxP. caudina), 172/51 (P. deltoides), I214 (P. euramericana cv.). The experiment were studied, repeated twice at Tokyo University Experiment Station, Tanasi, Tokyo. Young Cuttings of clones mentioned above were used for the experiment. The plants were grown in pots arranged in line and the pots were burried to their rims in the field. The measurements of height growth, leaf area and leaf longevity, were carried out at a week interval through a whole growing season, and the plants employed in the experiment, finally were dug out for the calculation of total dry weight increment. In both years, total dry weight increment were in proportion to both leaf area duration and total leaf area per plant, regardless of clonal differences. As a result, net assimilation rate was similar among all poplar clones. However, total leaf area per plant showed a significant difference among the clones used in the present experiment, and this is attributed to difference among clones in both years. Furthermore the difference in relatinship between total dry weight increment and total leaf area per plant among clones, were attributed to leaf longevity among clones in growing season. The differences in leaf longevity were remarkable among the clones in a season of vigorous growth, For example, OP20 continuously shed old leaves and regenerated new leaves in short interval, on the other hand, OP206 shed scarcely and their leaves were long-lived. The results as above mentioned, showed that the growth of poplar clones in this experiment highly depends on total leaf area per plant and leaf longevity through the growing season.