Photosynthesis in lightfleck areas of homobaric and heterobaric leaves

Pieruschka, Roland; Chavarrí-Krauser, Andrés; Schurr, Ulrich; Jahnke, Siegfried
April 2010
Journal of Experimental Botany;Apr2010, Vol. 61 Issue 4, p1031
Academic Journal
Leaves within a canopy are exposed to a spatially and temporally fluctuating light environment which may cause lateral gradients in leaf internal CO2 concentration and diffusion between shaded and illuminated areas. In previous studies it was hypothesized that lateral CO2 diffusion may support leaf photosynthesis, but the magnitude of this effect is still not well understood. In the present study homobaric leaves of Vicia faba or heterobaric leaves of Glycine max were illuminated with lightflecks of different sizes, mimicking sunflecks. Photosynthetic properties of the lightfleck areas were assessed with combined gas exchange measurements and chlorophyll fluorescence imaging. Lateral diffusion in homobaric leaves with an interconnected intercellular air space stimulated photosynthesis and the effect was largest in small lightfleck areas, in particular when plants were under drought stress. Such effects were not observed in the heterobaric leaves with strongly compartmented intercellular gas spaces. It is concluded that lateral diffusion may significantly contribute to photosynthesis of lightfleck areas of homobaric leaves depending on lightfleck size, lateral diffusivity, and stomatal conductance. Since homobaric leaf structures have been reported for many plant species, it is hypothesized that leaf homobary may have an impact on overall plant performance under conditions with a highly heterogeneous light environment.


Related Articles

  • The Blue Light-Specific Response of Vicia faba Stomata Acclimates to Growth Environment. Frechilla, Silvia; Talbott, Lawrence D.; Zeiger, Eduardo // Plant & Cell Physiology;Nov2004, Vol. 45 Issue 11, p1709 

    Stomata in epidermal strips from growth chamber-grown Vicia faba leaves opened less in response to white light than did stomata from greenhouse-grown leaves. Chlorophyll-mediated, red light-stimulated opening was similar in stomata from the two growth conditions, but stomata from the growth...

  • Low sink-induced stomatal closure alters photosynthetic rates of source leaves in beans as dependent on HO and ABA accumulation in guard cells. Xu, M.; Duan, W.; Fan, P.; Wu, B.; Wang, L.; Ma, L.; Archbold, D.; Li, S. // Russian Journal of Plant Physiology;May2014, Vol. 61 Issue 3, p397 

    Low sink demand provided by pod removal and stem girdling of beans ( Vicia faba, cv. Daqingshan) (-Sink) induced a significantly lower net photosynthetic rate ( P), stomatal conductance ( g), internal CO concentration ( C), and transpiration rate ( E) compared with pod and root sink retention...

  • Activities of Noncyclic and Alternative Pathways of Photosynthetic Electron Transport in Leaves of Broad Bean Plants Grown at Various Light Irradiances. Nikolaeva, M. K.; Bukhov, N. G.; Egorova, E. A. // Russian Journal of Plant Physiology;Jul2005, Vol. 52 Issue 4, p427 

    Activities of noncyclic and alternative pathways of photosynthetic electron transport were studied in intact leaves of broad been ( Vicia faba L.) seedlings grown under white light at irradiances of 176, 36, and 18 µmol quanta/(m2 s). Electron flows were followed from light-induced absorbance...

  • Seasonality of photosynthetic parameters in a multi-specific and vertically complex forest ecosystem in the Sierra Nevada of California. Laurent LM Misson; Kevin KPT Tu; Ralph RAB Boniello; Allen AHG Goldstein // Tree Physiology;Jun2006, Vol. 26 Issue 6, p729 

    Understanding seasonal variations of photosynthetic parameters is critical for accurate modeling of carbon dioxide (CO2) uptake by ecosystems. Maximum carboxylation velocity (Vcmax), maximum rate of electron transport (Jmax), leaf respiration in the light (Rday), light-saturated assimilation...

  • leaf.  // American Heritage Student Science Dictionary;2009, p199 

    A definition of the term "leaf" is presented. It refers to a flat, usually green plant part that grows on the stem and takes in carbon dioxide and sunlight to manufacture food by photosynthesis. Leaves consist of an outer tissue layer called the epidermis through which water and gases are...

  • Effects of Cytokinin Preparations on the Stability of the Photosynthetic Apparatus of Two Wheat Cultivars Experiencing Water Deficiency. Monakhova, O. F.; Chernyad'ev, I. I. // Applied Biochemistry & Microbiology;Nov/Dec2004, Vol. 40 Issue 6, p573 

    Carboxylase activity of the key enzyme of carbon metabolism, ribulose-bisphosphate carboxylase/oxygenase (RuBisCO; EC, and phosphoenolpyruvate carboxylase (PEPC; EC, as well as the intensity of carbon dioxide photosynthetic assimilation in young seedlings and adult leaves of...

  • C4 photosynthesis and water stress. Ghannoum, Oula // Annals of Botany;Feb2009, Vol. 103 Issue 4, p635 

    Background: In contrast to C3 photosynthesis, the response of C4 photosynthesis to water stress has been less-well studied in spite of the significant contribution of C4 plants to the global carbon budget and food security. The key feature of C4 photosynthesis is the operation of a...

  • Structural and functional alteration of photosynthetic apparatus in rice under submergence. Panda, Debabrata // Journal of Stress Physiology & Biochemistry;2012, Vol. 8 Issue 1, p95 

    Submergence induced alteration of photo-system II (PS II) structure and function was probed using fast O-J-I-P chlorophyll a fluorescence transient and CO2 photo-assimilation rate. Submergence resulted in an inhibition of CO2 photo-assimilation rate and reduction in leaf chlorophyll content in...

  • Polysomes from Vicia faba L. leaves bound to the actin cytoskeleton. Zak, EA; Sokolov, OI; Greengauz, OK; Bocharova, MA; Klyachko, NL // Journal of Experimental Botany;May1997, Vol. 48 Issue 310, p1019 

    The presence of polymeric actin in the polysome preparations from broad bean leaves (Vicia faba L. var. Russkie chernye) was detected on dob blots and under the electron microscope using the phalloidin-colloidal gold marker. The fractions enriched in the cytoskeleton-bound polysomes were...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics