Improving Photosynthetic Efficiency for Greater Yield

Abstract

Increasing the yield potential of the major food grain crops has contributed very significantly to a rising food supply over the past 50 years, which has until recently more than kept pace with rising global demand. Whereas improved photosynthetic efficiency has played only a minor role in the remarkable increases in productivity achieved in the last half century, further increases in yield potential will rely in large part on improved photosynthesis. Here we examine inefficiencies in photosynthetic energy transduction in crops from light interception to carbohydrate synthesis, and how classical breeding, systems biology, and synthetic biology are providing new opportunities to develop more productive germplasm. Near-term opportunities include improving the display of leaves in crop canopies to avoid light saturation of individual leaves and further investigation of a photorespiratory bypass that has already improved the productivity of model species. Longer-term opportunities include engineering into plants carboxylases that are better adapted to current and forthcoming CO(2) concentrations, and the use of modeling to guide molecular optimization of resource investment among the components of the photosynthetic apparatus, to maximize carbon gain without increasing crop inputs. Collectively, these changes have the potential to more than double the yield potential of our major crops.

Parâmetros genéticos e diversidade em progênies de Macaúba com base em características morfológicas e fisiológicas

“…Como a distribuição da espécie é muito mais ampla (MANFIO et al, 2012), é possível que, ao se amostrar uma maior quantidade de plantas em um número maior de regiões, seja possível identificar diferenças significativas. ZHU et al (2010), entretanto, demonstraram que os incrementos em produtividade obtidos via melhoramento da maioria das culturas não se deu pelo aprimoramento de características fisiológicas (como, por exemplo, capacidade de fixação de CO 2 ), mas sim pela melhoria dos componentes de produção (i.e. caracteres morfológicos).…”

Efficiency of chlorophyll in gross primary productivity: A proof of concept and application in crops

“…A vast literature exists on optimization patterns of plant productivity through maximizing the efficiency of use of photosynthetically active radiation (PAR) (Zhu et al, 2010;Gitelson et al, 2015;Retkute et al, 2015), as well as water, phosphorus, and nitrogen (N) (Anten et al, 1995;Anten et al, 1996;Buckley et al, 2002;Vico et al, 2013;Hikosaka, 2014;Osada et al, 2014) at multiple scales, from individual leaves to entire canopies (Field et al, 1995;Goetz and Prince, 1999). Many of these studies analyze the patterns of individual components in isolation, while fewer evaluate the combination of a limited number of components for assessing synergistic relations and trade-offs (Karlsson, 1994;Herppich et al, 2002;Ali et al, 2012;Xu et al, 2013).…”

A warm welcome for alternative CO2 fixation pathways in microbial biotechnology

“…However, a major challenge to fully realize sustainable autotrophic production of chemicals and fuels is the low growth rate, productivity and energy conversion efficiency of autotrophs. Excluding the energy loss photoautotrophs experience due to inefficient light‐harvesting (Blankenship et al ., 2011), another major energy loss occurs during the fixation of CO 2 in both photoautotrophs and chemolithoautotrophs (Zhu et al ., 2010). The large majority of autotrophs employ the relatively inefficient Calvin–Benson–Bassham cycle for CO 2 fixation (Fig.…”