Photosynthesis and leaf water relations in four American sycamore clones
Photosynthesis, transpiration, stomatal conductance, and xylem pressure potential were studied to examine clonal variation and clone-by-season interactions in rooted cuttings of four sycamore clones (Platanus occidentalis L.). These physiological parameters were measured during June through November of the second and third growing seasons in the field. Stomatal conductance, xylem pressure potential, and photosynthesis were higher in June-July than in August-November. The four clones did not differ significantly in yearly average photosynthetic rates, but clone 11 tended to have higher rates early in each growing season (June-July) than did the other three clones. Dry periods during August-September of the second season and during October of the third season apparently caused clone 11 to close its stomata more than clone 17, as indicated by significant clone-by-season interactions for reductions in stomatal conductance and transpiration late in the morning. Clone 17 was generally able to maintain high xylem pressure potential, stomatal conductance, and transpiration throughout the growing season, probably because of its large root system. 36 refs., 2 figs., 5 tabs.
- OSTI ID:
- 486436
- Journal Information:
- Forest Science, Journal Name: Forest Science Journal Issue: 4 Vol. 41; ISSN 0015-749X; ISSN FOSCAD
- Country of Publication:
- United States
- Language:
- English
Similar Records
Physiological indicators of nitrogen response in short-rotation sycamore plantations. [Platanus occidentalis L]
Water relations of populus clones