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Matthew P. Reynolds (Ed): Climate change and crop production

Food Sec. (2011) 3:111–112
DOI 10.1007/s12571-010-0090-3


Matthew P. Reynolds (Ed): Climate change and crop
CAB International, Wallingford, 292pp. 2010
Peter J. Gregory

Received: 29 November 2010 / Accepted: 29 November 2010 / Published online: 7 December 2010
# Springer Science+Business Media B.V. & International Society for Plant Pathology 2010

This volume is the first in a new series from CAB
International on climate change. Matthew Reynolds has
done a good job in bringing together a range of high-quality
authors to explore the issues raised for crop production by
the recorded and projected changing climate, in a book that
goes well beyond the conventional explorations of impact,
adaptation and mitigation. The 13 chapters comprising the
main elements of the book are grouped under four headings: predictions of climate change and its impact on crop

productivity (2 chapters); adapting to biotic and abiotic
stresses through crop breeding (5 chapters); sustainable and
resource-conserving technologies for adaptation to and
mitigation of climate change (3 chapters); and finally, new
tools for enhancing crop adaptation to climate change (3
chapters). As might be imagined from these headings, the
book is focussed on technological ways of dealing with the
changing climate, and there is little acknowledgement of
agriculture as a socially constructed activity, nor of the
contributions of markets, institutions and governance
arrangements in the way societies might organise themselves to cope with the challenges that climate change
Underlying the narrative is the realisation that, even
without the challenges posed by a changing climate, crop
production will need to increase substantially in the next
few decades to feed a growing population with, on average,
a higher standard of living than at present. Robert Watson
(Chief Scientific Advisor, Defra, UK) captures this well in
his introduction to the book, writing that “doubling food

P. J. Gregory (*)
Scottish Crop Research Institute (SCRI),
Dundee DD2 5DA, UK
e-mail: peter.gregory@scri.ac.uk

availability over the coming decades in the context of
climate change and other stresses will require advances in
crop research and agricultural practices, with emphasis on
the sustainable management of water and soils”. Throughout the book there are many attempts to marry these
multiple requirements of increased crop production, of new
crop genotypes that are less susceptible to biotic and abiotic
stresses, and of sustainable production practices to gain
multiple benefits in addition to coping with the challenges
of a changing climate.
Chapter 2 gives a measured account of what is known
and unknown about the future climate. It recognises that the
amount of warming will depend on the quantities of
radiatively-active gases emitted and suggests a 1-3°C global
increase in temperature by 2050, rising to 2-4°C by 2100.

Of course, for crop production, the changes in rainfall are
likely to be of greater importance than those in temperature
for much of the world. Here the projections are much more
uncertain because precipitation is driven by a wider range
of atmospheric processes than temperature, with regional
changes more likely than global ones. So, as today, there
may be drought in some places and waterlogging elsewhere
(but just more variable?). Overall, if temperature increases
by more than a degree or so, warming effects are likely to
decrease crop growth and yield. However, as the authors
state very clearly, the high degree of uncertainty about
impacts on crops “makes the prediction of effects on
agriculture difficult and can result in contradictory results”.
This is a good start because it frames well the challenge
facing crop scientists as they seek to develop appropriate
interventions to deal with an uncertain future.
The chapters on crop breeding deal with these uncertainties in different ways. The physiological and genetic
bases for adaptation of germplasm to heat and drought
stresses are only partially understood so, despite some


advances in the development of markers for these traits,
empirical multi-location testing of elite materials is still
required. The authors emphasise the need for better
characterisation of environments to assist with the deployment of markers for complex, adaptive traits but there is
silence as to how this might be achieved in practice in a
more climatically variable, and uncertain, world. Moreover,
while much literature predicts increases in the prevalence of
agricultural pests and diseases, only a handful of studies
have quantified the possible impacts. Several authors point
out that this has been a much neglected area of research
despite ample evidence that pests and diseases are major
causes of inefficiency and waste in our current production
systems. In part this is because of the difficulty of
separating the influences of normal, regional, seasonal
variations in weather from global climate change effects.
With or without climate change, though, the increases in
production required in the next few decades mean that
breeding for pest and disease resistance is an essential
component of germplasm improvement.
Chapters 9 and 10 on greenhouse gas mitigation and
conservation agriculture contain highly complementary
messages although they are written from different perspectives. Both highlight the need for research that more closely
integrates the links between sustainability, resource use
efficiency and the reduction of greenhouse gas emissions.
The links between these facets of crop production are
complex but there are currently few experiments or data
sets that contain simultaneous measurements of methane,
nitrous oxide and carbon dioxide emissions together with
those of carbon sequestration. Conservation agriculture,
based on minimal soil disturbance, permanent ground cover
and rotations, has been shown in several locations to result
in improved soil biological and physical fertility, better
nutrient cycling and crop growth. In rice production
systems, it can also result in less methane emissions when
flooding is reduced, but considerable care is required with
the method and timing of N fertiliser applications if nitrous
oxide emissions are also to be reduced. If conservation
agriculture is to play its full part as a mitigation strategy for

P.J. Gregory

greenhouse gas emissions, then the understanding of the
integrated effects of the practices on all greenhouse gases,
and the development of technologies and fertilisation
practices, will require the sort of research effort that has
previously been expended on production systems involving
inversion of the soil.
Unusually for a book on this subject, the final set of
chapters examines some of the new tools that are emerging
to assist with speeding up the rate of crop improvement.
Throughout the chapters the message is clear: that conventional and biotechnological approaches will be needed to
decrease the impact of agricultural production by increasing
the efficiency of production and simultaneously decreasing
greenhouse gas emissions. The chapter on the use of
biotechnology in agriculture combines both a conventional
account of the range of methodologies that are now
available with an original description in a series of boxes
distributed throughout the text of thirty examples of the
benefits that biotechnology has brought to crop improvement. These examples range from the well-known introgression of the Rht gene from the Japanese Norin-10 into elite
wheat varieties, through gamma-irradiation mutation of
cereals to produce, for example, Golden Promise, which
was a top malting barley in Scotland in the 1970s and 1980s,
to the recent use of TILLING populations to identify 196
new alleles in the A and B genome waxy genes (granule
bound starch synthase genes) in chemically induced mutants
of wheat. These examples should be compulsory reading for
all students of crop science. The final two chapters
demonstrate the vital role that mathematical and statistical
scientists play in modern programmes of crop improvement
and how their skills can be employed to understand a more
climatically uncertain future.
In summary, this is one of the best collections of papers
that I have read on the subject of climate change and crop
production and contains much to challenge the reader. Its
implicit message to simultaneously research crop improvement through breeding, and crop husbandry through
improved pest, disease, tillage, fertiliser and water management is to be applauded.

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