Carbonic anhydrase (CA) catalyzes the first biochemical step of the carbon-concentrating mechanism of C4 plants, and in C4 monocots it has been suggested that CA activity is near limiting for photosynthesis. Here, we test this hypothesis through the characterization of transposon-induced mutant alleles of Ca1 and Ca2 in maize (Zea mays). These two isoforms account for more than 85% of the CA tr...

Carbonic anhydrase (CA) catalyzes the first biochemical step of the carbon-concentrating mechanism of C4 plants, and in C4 monocots it has been suggested that CA activity is near limiting for photosynthesis. Here, we test this hypothesis through the characterization of transposon-induced mutant alleles of Ca1 and Ca2 in maize (Zea mays). These two isoforms account for more than 85% of the CA tr...

This experiment was consisted in 2007-2008 and 2008-2009 cropping seasons in field Agriculture and Research center of West-Azerbaijan. The experimental design was split-split-plot experiments using Randomized Complete Block Design (RCBD) with 3 replications. The factor main was consisted irrigation treatment including optimum irrigation, moderate stress and sever stress where irrigation was don...

CURRENT SCIENCE, VOL. 101, NO. 1, 10 JULY 2011 47 This is the fifth article on the theme ‘Photosynthesis and the Global Issues’, being guest-edited by Govindjee, George C. Papageorgiou and Baishnab C. Tripathy. The first article by Lars Olof Björn and Govindjee discussed the evolution of photosynthesis and the chloroplasts and was published in 2009 (96, 1466–1474). The second article, by Maria ...

CO(2) exchange between air and leaf is conceived as a current along a resistor with a respiratory current, unaffected by CO(2) concentration, entering the resistor. The conclusion follows that a plant placed in an atmosphere free of CO(2) will increase the CO(2) concentration to the compensation concentration along a curve determined by the resistor and the volume of the atmosphere. This was ve...

This research was conducted in 2007 and 2008 cropping seasons in the experimental field of Shahid Salemi, Ahvaz, south west of Iran. In each year, the study consisted of a split split-plot experiment, using Randomized Complete Block Design (RCBD) with three replications. Four irrigation levels including irrigationoff at the 8 leaf, the 12 leaf and the tasseling stages and optimum irrigation wer...

Accurate representation of photosynthesis in terrestrial biosphere models (TBMs) is essential for robust projections of global change. However, current representations vary markedly between TBMs, contributing uncertainty to projections of global carbon fluxes. Here we compared the representation of photosynthesis in seven TBMs by examining leaf and canopy level responses of photosynthetic CO2 a...

Photosynthesis has provided life-energy for the biosphere during most of earth’s history. It provides us with all our food and fuel for our vehicles, and much of our building materials and other commodities. When our society now faces the big energy crisis, this ancient process may come to our rescue, both in the form of biofuel produced by plants and in novel, technologically modified versions...

1 Department of Physical Sciences, Alabama State University, Alabama, AL, USA 2 Institute of Plant Physiology, Russian Academy of Sciences, Moscow, Russia 3 Institute of Basic Biological Problems, Russian Academy of Sciences, Moscow, Russia 4 Department of Chemistry, Center of Climate Change and Global Warming, Institute for Advanced Studies in Basic Sciences, Zanjan, Iran 5 Departments of Bioc...

Canopy photosynthesis has typically been estimated using mathematical models that have the following assumptions: the light interception inside the canopy exponentially declines with the canopy depth, and the photosynthetic capacity is affected by light interception as a result of acclimation. However, in actual situations, light interception in the canopy is quite heterogenous depending on env...