JOURNAL ARTICLE

Effects of growth and measurement light intensities on temperature dependence of CO(2) assimilation rate in tobacco leaves

Wataru Yamori, John R Evans, Susanne Von Caemmerer
Plant, Cell & Environment 2010, 33 (3): 332-43
19895395
Effects of growth light intensity on the temperature dependence of CO(2) assimilation rate were studied in tobacco (Nicotiana tabacum) because growth light intensity alters nitrogen allocation between photosynthetic components. Leaf nitrogen, ribulose 1.5-bisphosphate carboxylase/oxygenase (Rubisco) and cytochrome f (cyt f) contents increased with increasing growth light intensity, but the cyt f/Rubisco ratio was unaltered. Mesophyll conductance to CO(2) diffusion (g(m)) measured with carbon isotope discrimination increased with growth light intensity but not with measuring light intensity. The responses of CO(2) assimilation rate to chloroplast CO(2) concentration (C(c)) at different light intensities and temperatures were used to estimate the maximum carboxylation rate of Rubisco (V(cmax)) and the chloroplast electron transport rate (J). Maximum electron transport rates were linearly related to cyt f content at any given temperature (e.g. 115 and 179 micromol electrons mol(-1) cyt f s(-1) at 25 and 40 degrees C, respectively). The chloroplast CO(2) concentration (C(trans)) at which the transition from RuBP carboxylation to RuBP regeneration limitation occurred increased with leaf temperature and was independent of growth light intensity, consistent with the constant ratio of cyt f/Rubisco. In tobacco, CO(2) assimilation rate at 380 micromol mol(-1) CO(2) concentration and high light was limited by RuBP carboxylation above 32 degrees C and by RuBP regeneration below 32 degrees C.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
19895395
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"