Mediterranean clues towards the improvement of photosynthesis in crops
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Jeroni Galmés [1]
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[1] Universitat de les Illes Balears
Universitat de les Illes Balears
Palma de Mallorca, España
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- Localización: SEFV 2011: programa de sesiones y resúmenes de conferencias plenarias e invitadas / coord. por Vicent Arbona Mengual, Rosa María Pérez Clemente, María Fernanda López Climent, Aurelio Gómez Cadenas, 2011, ISBN 978-84-8021-805-4, pág. 27
- Idioma: inglés
- Texto completo no disponible (Saber más ...)
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Resumen
In 1961, Calvin was awarded for the Nobel Prize for elucidating the PCRC. Although it mightseem less important, 50 years later I have the honor to receive the Sabater Award for youngresearcher in Plant Biology by SEFV. During this time, world population has increased by 4billion, and it is projected to pass 9 billion by 2050, increasing the demand for food andbioenergy. Despite great advances, crop productivity gains through traditional breeding begin tolag, and strategies to improve crop yield potential have begun to examine aspects of chargingphotosynthesis to drive a new “green revolution”. Compounding the problem are theuncertainties of climate change impact on agriculture, foreseeing a decrease in yield due towater and temperature limitations on carbon metabolism.Unraveling the myriad of processes developed by wild vegetation to adapt the photosyntheticmachinery to highly stressing environments could supply useful clues towards the improvementof crop photosynthesis under stress. In this sense, adaptation displayed by the Mediterraneanvegetation, exposed to water, light and temperature stresses, becomes a clear candidate toexplore.Central to these strategies is addressing the limitations imposed by, on one hand, the leafresistances to water and CO2 and, on the other, by Rubisco. Under water stress, stomatal andmesophyll conductances to CO2 decrease, lowering the availability of substrate forcarboxylation (Cc). The high temperatures experienced by Mediterranean plants further decreaseCc, by lowering mesophyll conductance and the ratio CO2/O2 dissolved in the liquid media.Overall, important pressures have operated on Rubisco in arid environments, selecting thoseversions with more affinity for the scarce CO2. Despite of it, photosynthetic models predict onlymoderate gains in leaf photosynthesis if crops’ native Rubiscos were replaced by the wildimproved versions, although such improvements largely increase when considering situations ofpartial stomatal closure. The transference of the genes encoding Rubisco from natural plants tothe tobacco plastome has been successful, and the resulting recombinant enzyme presentsimproved characteristics. Despite the promising progresses, analyses of the transplantomic linesrevealed a number of failures demanding further research to secure successfulness towardsenhanced photosynthetic capacity in crops.
