Food security and climate change: on the potential to adapt global crop production by active selection to rising atmospheric carbon dioxide

Abstract

Agricultural production is under increasing pressure by global anthropogenic changes, including rising population, diversion of cereals to biofuels, increased protein demands and climatic extremes. Because of the immediate and dynamic nature of these changes, adaptation measures are urgently needed to ensure both the stability and continued increase of the global food supply. Although potential adaption options often consider regional or sectoral variations of existing risk management (e.g. earlier planting dates, choice of crop), there may be a global-centric strategy for increasing productivity. In spite of the recognition that atmospheric carbon dioxide (CO 2 ) is an essential plant resource that has increased globally by approximately 25 per cent since 1959, efforts to increase the biological conversion of atmospheric CO 2 to stimulate seed yield through crop selection is not generally recognized as an effective adaptation measure. In this review, we challenge that viewpoint through an assessment of existing studies on CO 2 and intraspecific variability to illustrate the potential biological basis for differential plant response among crop lines and demonstrate that while technical hurdles remain, active selection and breeding for CO 2 responsiveness among cereal varieties may provide one of the simplest and direct strategies for increasing global yields and maintaining food security with anthropogenic change.

Evolutionary and Ecological Responses to Anthropogenic Climate Change

“…Although it may be difficult to simulate future climates precisely because of uncertainties in projections (Shaw and Etterson, 2012), multifactorial manipulative experiments can tease apart the effects of different agents of selection on the evolution of complex traits, investigate the interactive effects of these variables, and more closely resemble future climatic conditions. As an example of the need for multifactorial studies, elevated atmospheric CO 2 concentration alone could enhance growth, hasten development, and increase fecundity, but reductions in performance from drought and warmer temperatures could offset those effects (Ainsworth and Long, 2005;Long et al, 2006;Ziska et al, 2012). Experiments run in controlled environmental facilities can model past, present, and future climatic conditions to test adaptation to climate in isolation from other environmental factors.…”

Can a collapse of global civilization be avoided?

“…But climatic conditions may change sufficiently that those industrial high yields can themselves no longer be sustained [45]. Thus, reducing the chances of a collapse calls for placing much more effort into genetic and ecological research related to agriculture [75] and adopting already known environmental-friendly techniques, even though that may require trading off immediate corporate profits for social benefits or long-term sustainability [3].…”

Sunflower crop and climate change: vulnerability, adaptation, and mitigation potential from case-studies in Europe

“…Breeding for new varieties better adapted to thermal shocks (heat, cold) and drought is often suggested as the major long-term adaptation. The breeding strategies aim at improved water efficiency, improved drought stress tolerance, and increased responsiveness to higher atmospheric [CO 2 ] (Ceccarelli et al, 2010;Ziska et al, 2012). However, prospective results of plant breeding are unforeseeable and the impact assessment strongly depends on the assumptions made on breeding progress (Graß et al, 2015).…”