Photosynthetic Adaptation to Light Intensity in Sakhalin Knotweed ( Polygonum sachalinense )

• Published in: Weed Science
• Main Authors: Patterson, David T., Longstreth, David J., Peet, Mary M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1977
• Subjects: Plant Science; Agronomy and Crop Science; Sakhalin
• Online Access: http://dx.doi.org/10.1017/s0043174500033555; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0043174500033555

The capacity for photosynthetic acclimation to light intensity in Sakhalin knotweed ( Polygonum sachalinense F. Schmidt) was studied by growing plants in four light environments [out-of-doors in full sun and under 50% shade, and in a growth chamber at 800 μ E m 2 sec -1 photosynthetically active radiation, 400 to 700 nm (PAR) and 150 μ E m -2 sec -1 PAR], and then determining, with an infrared gas analyzer (IRGA), the photosynthetic rates of single leaves exposed to a range of light intensities from 100 to 2000 μ E m 2 sec -1 PAR. The plants grown in high light had higher photosynthetic rates throughout the range of 100 to 2000 μ E M -2 sec -1 PAR. Maximum photosynthetic rates were 37 mg CO 2 dm -2 h -1 for plants grown in full sun out-of-doors and 16.5 mg CO 2 dm -2 h -1 for plants grown in low light in the growth chamber. There was no indication of positive adaptation to low light intensity in Sakhalin knotweed. Differences in light-saturated photosynthetic rates were closely related to differences in mesophyll conductance and chlorophyll content per unit leaf area.