Abstract

The global food economy is vast and technologically advanced, but none the less prone to substantial negative outcomes in poor weather years. The economic gains or losses associated with climate change will depend on the pace of climate change, the response of cropping systems - including the vast number of growers, researchers, extension agents and others who determine how croplands are managed - to these changes, and the response of global markets to resulting changes in crop yields. We...

Adaptation of Rice to Heat Stress

Adaptation to increasing heat stress is likely to be more difficult than to changes in hydrology, mainly because managed stress screening is difficult for national breeding programmes that may not have access to trial sites at which high temperatures can be reliably expected at appropriate growth stages. However, Wassman et al. (2009b) noted that there are several rice-producing regions in which temperatures during the sensitive flowering stage exceed 36 or even 40 C. Germplasm from these areas...

Adapting Crops to Climate Change a Summary

Reynolds and Rodomiro Ortiz The Intergovermental Panel on Climate Change (IPCC, 2009) indicates that rising temperatures, drought, floods, desertification and weather extremes will severely affect agriculture, especially in the developing world. While the convergence of population growth and climate change threatens food security on a worldwide scale, the opportunity also exists to address the pernicious threat of famine. Indeed the prerequisites to develop a globally coordinated...

Approaches and Technologies for Genetic Improvement

Crop improvement needs to be appropriate for specific circumstances (local cultivation conditions and practices) as well as targeting specific crops and end uses of these crops. The traits involved in yield production and in efficient resource utilization are complex and involve many genes. The classical approach is breeding for phenotypes. Genetic analysis provides molecular markers to facilitate MAB and no knowledge of the precise mechanisms or specific genes controlling the traits is...

Building knowledge and understanding

An 'explosion' in plant genetics and genom-ics research as well as the quantity of information about plant genome structure, has resulted in a 'technology gap'. Resource development has exceeded the ability to solve practical plant breeding problems using those resources. This gap is being closed by providing tools and methods to breeders to help them identify, and select, traits and underlying genes. order to fully exploit these genetic mechanisms (Reynolds et al., 2005). Developing new crop...

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Chemical control

Chemical control is among the options available for limiting yield losses (Oerke, 2006). Intrinsic pest pathogen characteristics (e.g. diapause, life cycle, generation time, minimum, maximum and optimum growth temperatures, and host interaction) and intrinsic ecosystem characteristics (e.g. monoculture and biodiversity) lead to changes in microorganism populations. An increase in pest infestation might lead to greater use of chemical pesticides to control them. It has been estimated that the...

China

1 2 3 4 5 6 Local temperature change ( C) 1 2 3 4 5 6 Local temperature change ( C) Fig. 3.1. Crop model estimates of rice yield changes for different levels of warming for (a) China and (b) India, as reported in various studies. Black dots indicate effects without CO2 fertilization, and grey dots with CO2 fertilization, with arrows connecting points from the same study. The only difference between points connected by arrows is thus the simulated effect of CO2. Values were derived from three...

Climate Change Crop Production

Climate change is a major environmental challenge to the world today, with significant threats to ecosystems, food security, water resources and economic stability overall. In order to understand and research ways to alleviate the effects of climate change, scientists need access to information that not only provides an overview of and background to the field, but also keeps them up to date with the latest research findings. This series addresses all topics relating to climate change, including...

Climate Change Predictions

The IPCC TAR (2001) provided a baseline for the prediction of climatic changes at broad scales by using historical measurements and future predictions made by several global circulation models or GCMs in addition to what the first and second assessment reports had previously outlined (IPCC, 1990, 1995), but included the definitions of more politically oriented scenarios (i.e. the Special Report on Emissions Scenarios (SRES) scenarios IPCC, 2000) rather than the IS92 emission scenarios described...

Conclusions

GIS and crop simulation modelling will see increasing use in climate change research and in applications of research in decision making. Maps are especially valuable for allowing people to understand how climate change impacts, as well as possible adaptations vary, across the landscape. Examples highlighted in this review illustrate how the combination of GIS and crop models may assist with policy and breeding decisions in relation to climate change. Knowledge surrounding the potential shifts...

Conclusions Prospects

Climate change poses both threats and opportunities to crop production. Even where it is possible to escape any effects of climate change by altering spatial or temporal patterns of production, genetic improvement aimed at improving crop performance will occur and have an environmental foot print. Both conventional and biotechnologi-cal approaches are necessary to decrease the impact of agricultural production by increasing the efficiency of production, minimizing storage losses and decreasing...

Contents

1 Adapting Crops to Climate Change a Summary 1 Matthew P. Reynolds and Rodomiro Ortiz Predictions of Climate Change and its Impact on Crop Productivity 2 Scenarios of Climate Change Within the Context of Agriculture 9 Andy Jarvis, Julian Ramirez, Ben Anderson, Christoph Leibing and Pramod Aggarwal 3 Economic Impacts of Climate Change on Agriculture to 2030 38 Adapting to Biotic and Abiotic Stresses Through Crop Breeding 4 Preventing Potential Disease and Pest Epidemics Under a 5 Breeding for...

David Hodson and Jeffrey White

The challenges that climate change presents to humanity require an unprecedented ability to predict the responses of crops to environment and management. Geographic information systems (GIS) and crop simulation models are two powerful and highly complementary tools that are increasingly used for such predictive analyses. The role of both technologies in predicting future situations centres around extrapolation. For GIS, extrapolation from the past based on correlation in a very loose sense...

Delivery Pathways and Processes

MAS has enhanced conventional breeding methods by providing greater flexibility and new selection strategies than were previously possible. The delivery pathway for biotechnology has been facilitated by training of a new generation of plant breeders who have a thorough knowledge of molecular biology, genetics and heritability. Some of the key factors influencing marker application are listed in Table 12.6. From 1995 a new industry rapidly developed to generate GM plants, but there have only...

Fixedeffect Linear Bilinear Models

Williams (1952) was the first to link the Eqn 14.1 model with principal components (PC) analysis by considering the model y + T + Xai Yj + ej where X is the largest singular value of ZZ' and Z'Z (for Z yy - yy.), and ai and yi are the corresponding eigenvectors. Gollob (1968) and Mandel (1969, 1971) rediscovered and extended Williams' (1952) work by considering the bilinear GE term as (t 8) aik y jk. Thus, the general formulation of the linear-bilinear model is

Forecasting models

Modelling is a tool for developing early warning systems and reducing the application of chemicals. Forecasting models need to be valid and to predict actual field observations adequately. With climate change, the challenge is to take account of the variability in disease epidemiology. Disease forecasting systems using non-linear responses to temperature and leaf wetness offer more potential for representing these effects (Bourgeois et al., 2004). However, although modelling is becoming more...

Functional Biology of Disease Suppressive Soils

Disease suppressive soils have been identified for a number of plant pathogens, with a few of the more prominent examples including those soils suppressive to Fusarium wilt (Rouxel et al., 1979 Scher and Baker, 1980), potato scab (Menzies, 1959), cyst nematode (Westphal and Becker, 1999), Rhizoctonia root rot (Henis et al., 1979 Barnett et al., 2006 Garbeva et al., 2006), Pythium root rot (Adiobo et al., 2007) and take-all of wheat (Cook and Rovira, 1976). Harnessing the potential of these...

Gene expression or functionality

Apart from the evolutionary forces influencing population diversity, climate change may induce phenotypic change leading to differences in gene expression or functionality, which also tend to modify pathosystems. Increases in temperature can modify host physiology and resistance by changing gene expression and activity. For example, temperatures above 20 C deactivate temperature-sensitive resistance to stem rust in oat cultivars with Pg3 and Pg4 genes (Maertens et al., 1967). In tetraploid...

Genetic Improvement of Yield

Crop improvement is usually targeted at improving yields, whether by husbandry or genetic improvement. Breeding improvements are generally aimed at intrinsic increases in yield potential or at the alleviation of either biotic (Brown, 2002) or abiotic (Takeda and Matsuoka, 2008) stresses. As an example, major improvements in inherent yield potential of wheat have occurred over the last 50 years, with the major impact being the introduction of dwarfing genes (the 'Green Revolution'), which...

Global circulation models SRES emissions scenarios and uncertainty

Global circulation models, also often referred as 'global climate models', 'general circulation models' or simply GCMs, are based on well-established physical principles and have been demonstrated to reproduce observed features of recent (IPCC, 2001, 2007) and past climatic changes accurately as evaluation methods have become available (IPCC, 2007 Pierce et al., 2009). Currently, more than a dozen centres around the world develop climate models to enhance our understanding of climate and...

Global scale economic impacts

Given these aggregate yield impacts, what might the economic effects be A simple estimate would be to multiply the percentage change in yield by the global production and price of each crop, currently roughly 700 t year and US 150 t in the case of maize. Thus, a 14 drop in yields would correspond to roughly US 15 billion year at current production and price levels, and even more as global production grows. However, the price effects of these production changes will lead to adjustments in the...

Global scale yield changes

To begin, one can consider impacts of climate change on average global yields of major commodities. A recent study by Tebaldi and Lobell (2008) attempted to estimate the probability distribution function (pdf) of impacts for maize, wheat and barley - three crops for which the relationships between average yields and crop-area weighted temperature and precipitation are relatively strong. The authors computed a pdf for temperature and precipitation changes, based on a Bayesian analysis of 18...

Hans Joachim Braun Gary Atlin and Thomas Payne

Plant breeding, using the combined potential of conventional, molecular and genetically modified technologies, will provide cultivars with greatly enhanced nutrient and water-use efficiency, enhanced tolerance to heat and drought, resistance to diseases and appropriate end-use and nutritional quality, and, possibly most important, increased ability to cope with the increasing extremes in temperature and precipitation occurring at one location over years. Modern crop cultivars developed by seed...

Heat

High temperature stress is relatively predictable in some regions (e.g. parts of South Asia and sub-Saharan Africa) increasing slowly in a way that permits plants to acclimate. In other regions, however, stress can occur quite suddenly and may be accompanied by desiccating winds (e.g. the Great Plains in the USA or North Africa). An additional dimension to heat stress is relative humidity (RH). In moist tropical regions, high RH further exacerbates heat stress in two ways. Saturated air (i)...

Impacts of Climate Change on Agriculture

The impacts of climate change on agriculture are expected to be widespread across the globe, although studies suggest that African agriculture is likely to be most affected due to heavy reliance on low-input rainfed agriculture and due to its low adaptive capacity (Mertz et al., 2009). Broadly speaking, climate change is likely to impact crop productivity directly through changes in the growing environment, but also indirectly through shifts in the geography and prevalence of agricultural pests...

Impacts on pest and disease prevalence

Global climatic change is also likely to impact agriculture through shifts in patterns of pests and diseases (organisms that range from weeds, certain herbivorous insects, arthropods and nematodes to fungi, bacteria and viruses). Rising temperatures and variations in precipitation, humidity and other abiotic factors are affecting the diversity and responsiveness of agricultural pests and diseases across diverse geographic ranges (Rosenzweig and Liverman, 1992 Estay et al., 2009). Of all the...

Increasing Amounts of C Fixed Per Unit Water

An important goal of crop improvement to decrease GHG emissions and mitigate the environmental impact of agriculture is to decrease the gap between yield potential and actual yield by overcoming the negative effects on yield of abiotic and biotic stress. Drought stress has been identified as a major target. Since the traits important in determining yield under stress-free environments are also important in water-limited environments, the yield potential of crops is strongly correlated with...

Induced genetic variation

Sexual reproduction has many barriers, such as hybrid infertility, that prevent the use of wild germplasm in plant breeding. Mutagenesis can be used to induce, or create, new genetic variability. Radiation, such as gamma-rays, or chemicals such as alkylalkanesulfonates, can be used to generate variation from which plants with desirable characteristics can be selected. Example 4 The first successful mutant barley with 'stiff straw' (cultivar 'Pallas', 1958) was generated because of a new process...

Infection

The infection or penetration of a plant host by infectious propagules is also determined by specific environmental conditions. Fungal pathogens usually require high relative humidity or even free water for infection. The infection process is limited by the duration of surface wetness or high humidity in most terrestrial environments (Magarey et al., 2005). Various components of climate change are likely to affect the level and duration of humidity in the environment of pathogens, including...

Info

Comparison of relative distribution of irrigated spring wheat mega-environments (MEs) in South Asia. ME1 is for favourable climatic conditions, and ME5 is for regions where heat stress is expected. (a) MEs under current climatic conditions. (b) MEs for a 2050 scenario (2 x CO2, com3 model Govindasamy et al., 2003). From Hodson and White (2007) reprinted with permission from Cambridge University Press. Fig. 13.3. Comparison of relative distribution of irrigated spring wheat...

Interaction of heat and drought with elevated CO2

By 2050 atmospheric CO2 levels are expected to be around 550 ppm. In C3 species such as wheat and rice, the elevated CO2 level is expected to increase productivity due to the improvement of CO2 diffusion through stomata and a consequent effect on photosynthesis. However, a complex of interactions can arise among plant development, growth and environment variables. Plants that have acclimated to high CO2 and grown new leaves over time (with typically fewer and smaller stomata) do not show the...

Introduction

The consequences of climate change for the modern food economy will depend on three main factors. First is the nature of climate change itself. For example how fast will temperatures rise, and where and by how much will rainfall patterns change In large measure these changes will depend on emissions of greenhouse gases (GHGs) and the response of the climate system to these gases, although changes in aerosols and land use can also affect local climate trends, particularly in agricultural regions...

Inundation

Many saltland habitats are also subject to inundation, but the impacts of this combination of stresses on the growth and survival of crop plants are poorly understood. Within cereal crops, nearly all inundation research has focused on rice under non-saline conditions (e.g. Setter et al, 1987, 1988). Our understanding of the kinds of physiological adaptations that are important to inundation come largely from studies of rice and Fig. 6.3. Relationship between the porosity of adventitious roots...

Jose Crossa Juan Burgueno and Mateo Vargas

Annual crop production will be greatly affected by increases in mean temperature and climate change, which will be likely to reduce agricultural production and decrease food availability. Plant breeding will play an important role in developing more sustainable lines and varieties for less favourable environments that will be subjected to extreme changes in biotic and abiotic stresses. Breeding cultivars with enhanced tolerance to heat, moisture stress and salinity is essential for long-term...

Maize breeding

Maize is grown on approximately 150 million ha worldwide, of which 100 million ha is in developing countries, though the latter account for less than half of total production. Over the last 100 years, maize has been the major commercial success of cereals. Adaptation of the crop in the main production areas of the USA is now expanding further into the more marginal western areas (Mason et al., 2008), while production and adoption of hybrids has also begun to increase more rapidly in tropical...

Nature of adaptive change

Biological organisms undergo adaptive change as they acclimatize to new environments. Many adaptive characteristics result from the prevailing environment influencing expression of genes related to adaptation. Genes are also subject to constant change random changes or 'mutations' can occur through internal errors in DNA repair CAB International 2010. Climate Change and Crop Production (ed. M.P. Reynolds) and replication or when subjected to external influences such as ultraviolet irradiation....

Physiological effects of water stress

Water deficit leads directly to stomatal closure and reduces the potential for CO2 fixation relative to well-watered plants. Closure is caused both by hydraulic effects and by chemical signalling, the latter being an adaptive function that increases transpiration efficiency (Davies et al., 2005) and is the basis of the common practice of deficit irrigation in water-scarce environments (Fereres and Soriano, 2007). A consequence of reduced transpiration rate may be that plant organs experience...

Predicted changes in temperature

The FAR of the IPCC (2007) describes changes in temperature at different levels of the atmosphere. We will focus only on near-to-surface changes on land as those changes directly influence agricultural production. Results of different GCMs indicate that in both the TAR and the FAR (IPCC, 2001, 2007) global temperatures are to increase. Land and sea surface temperatures will increase at rates never experienced before, and, depending on the emission scenario, these changes are reversible to a...

Predictions of Climate Change and its Impact on Crop Productivity

In the first section of the book, chapters by Lobell and Burke (Chapter 3) and Jarvis et al. (Chapter 2) address predictions of climate change over the next 30+ years and their likely biological and economic consequences CAB International 2010. Climate Change and Crop Production (ed. M.P. Reynolds) in the context of crop productivity. Their main points are summarized as follows. Developing countries will be affected most for three reasons (i) climate change will have its most negative effects...

Regional impacts

Although global scale economic impacts are important, especially for consumers tied to global markets, local and regional deviations from global trends will also be of interest. In particular, one may wish to know how production will change in areas where the ability to purchase food on global markets is more limited, a situation that characterizes many of the poorest areas in the world where subsistence agriculture is common and local prices respond directly to changes in local production....

Regulation

GM organisms are subject to tight regulatory approvals in countries where they are developed and grown. These regulations allow GM research only in suitably approved containment facilities and by organizations and staff who have the appropriate qualifications and experience. For GM crops, field evaluation is an essential component of the development and delivery process. Special approvals are required for conducting such trials. In some countries, the approval process is relatively...

Rice Systems CH4 and N2O Mitigation

Rice requires special attention in terms of GHG emissions due to the unique semi-aquatic nature of this crop. About 90 of Area harvested (ha) 0-100,000 100,001-500,000 500,001-750,000 750,001-1,000,000 1,000,001-3,000,000 3,000,001-5,000,000 5,000,001-28,074,000 Fig. 9.2. Maize production worldwide 2007 (data from FAOSTAT, 2009 map drawn by Dave Hodson, CIMMYT). Table 9.1. Assessing mitigation potentials in agriculture (from Barker et al., 2007). Restoration of cultivated organic soils 1260...

Salinity

Soil salinity affects plant growth and survival because ions (mainly Na+ and Cl-, but also Ca2+, Mg2+ and SO42- Richards, 1954) increase in the soil solution to concentrations that adversely decrease the availability of water to the plant (the 'osmotic effect'). The accumulation of these ions in the plant tissues also impairs plant metabolism and growth (the 'toxic effect') (Greenway and Munns, 1980). The effects differ in their timing the osmotic effects are immediate, but the ion toxicity...

Sexual and asexual reproduction

By affecting the distribution of gene diversity among individuals in a population, reproduction is a strong driver of evolution, particularly for pathogens undergoing regular recombination, but also for asexually reproducing pathogens because environmental conditions promote the selection of adapted individuals. Phytophthora infestans, the causal agent of potato late blight, has often caused major damage as the fungus has moved into new countries. The Irish famine, from 1844 to 1849, is a...

Survival

Changes in the environment can initially affect the survival rate of pathogens and pests. Higher minimum temperatures and reduced frequency or intensity of cold days favour the survival of pests with the falling temperatures (Coakley et al., 1999). Leaf rust epidemics caused by Puccinia triticina in wheat in Kansas, USA were found to cause higher yield losses over nearly two decades in areas where the pathogen could overwinter (Eversmeyer and Kramer, 2000). Likewise, if the frost line moves...

Technology Access

The patent system grants monopoly rights to patent owners so that they can exclude others from practising patented technologies for a period of time. The quid pro quo is that society is afforded free access to those inventions upon the expiry of the patent. Large international companies have scrambled to gain market monopoly returns by assembling large patent portfolios. These portfolios not only include genetic technologies per se, but also so-called 'enabling' technologies such as...

Titles in Preparation

Crop Stress Management and Global Climate Change Edited by Jose L. Araus and Gustavo A. Slafer Cold Adaptation and Climate Change a Mechanistic Perspective Edited by Ken Story and Karen Tanino 7 Multi-location Testing as a Tool to Identify Plant Response to Hans-Joachim Braun, Gary Atlin and Thomas Payne 8 Genetic Approaches to Reduce Greenhouse Gas Emissions Increasing Carbon Capture and Decreasing Environmental Impact 139 Martin A.J. Parry and Malcom J. Hawkesford Sustainable and...

Variation Natural genetic variation

Genetic variation can be exploited by introgression genes are moved into the cultivated gene pool by continuously backcrossing with the cultivated parent. While this takes many generations, it is the most widely adopted method for expanding available variation in a breeding programme. However, it can be a slow process. Example 1 Improved resistance of cultivated European spring barley to mildew has been achieved by introgressing an Ethiopian landrace mlo-11 (J0rgensen, 1992). Norman Borlaug...

Variation within existing germplasm pools

Waterlogging Tolerance Geens

Genetic variation within cultivated crops has been identified, but it is unclear if there exists sufficient diversity to deliver the range in adapted phenotypes required for adequate yield gains. It is difficult to accurately determine the level of diversity within crops due to differences in genotypes selected for studies and the contrasting experimental and environmental conditions in which they are screened (see the 'Stresses and the Key Plant Physiological Adaptations' section). Perhaps an...

Management of Biologically Mediated Soil Suppressiveness

Various attributes of a cropping system including plant species (Garbeva et al., 2006), input system (organic versus conventional) (Workneh et al., 1993 van Bruggen, 1995 Liu et al., 2007), tillage (Peters et al., 2003) and fertilization (Smiley, 1978), among others, will influence ecological processes that determine microbial community structure and function, including its capacity to induce suppression of soilborne plant pathogens. These observations imply that, given knowledge of the...

Knowledge Data Technology and Intellectual Constraints

The accuracy of crop models is constrained by uncertainty over physiological processes related to climate change. This includes effects of CO2 and temperature on photosynthesis (Crafts-Brandner and Salvucci, 2004) and net crop responses (Long et al., 2006 Tubiello et al., 2007). There also is evidence that CO2 affects crop growth and development through mechanisms besides carbon fixation and transpiration. Elevated CO2 can either accelerate or slow development, depending on the plant species...

Mutation and genetic drift

Mutation is the ultimate source of genetic variation, leading directly to changes in the DNA sequence of individual genes and thus creating new alleles in populations (McDonald and Linde, 2002). The loss of alleles over time, or genetic drift, can also generate new diseases through the selection of gene combinations that can adapt to a new ecosystem. The evolutionary potential of a small population is limited, but its adaptation capability to a new environment should not be underestimated....

Crop Production N2o Emissions

Annual global consumption of N fertilizer was expected to exceed 100 million t in 2007-2008 (Heffer and Prud'homme, 2007), while in 1965 it was only 20 million t. During 2006 approximately 70 of that was applied in developing countries (IFA, 2009). In the growing season 2006-2006 07 wheat and maize both contributed 17.3 of world usage, followed by rice with 15.8 . Together wheat, maize and rice consume 50 of all N fertilizer produced around the world (Heffer, 2009). However, only half of the N...

References

Anagnostakis, S.L. (1987) Chestnut blight - the classical problem of an introduced pathogen. Mycologia 79, 23-37. Anderson, P.K., Cunningham, A.A., Patel, N.G., Morales, F.J., Epstein, P.R. and Daszak, P. (2004) Emerging infectious diseases of plants pathogen pollution, climate change and agrotechnology drivers. Trends in Ecology and Evolution 19, 535-544. Baker, K.M., Kirk, W.W., Stein, J.M. and Andresen, J.A. (2005) Climatic trends and potato late blight risk in the upper Great Lakes Region....

Rice Megaenvironments and Climate Change

Rice, eaten by about three billion, directly supports more people than any other staple food (Maclean et al., 2002). Rice adaptation is affected by many environmental factors, including day length and temperature, and soil factors such as salinity, aluminium toxic-ity and iron toxicity. However, within broad bands of latitude, rice MEs tend to be defined in terms of hydrology, water availability and maximum water depth (Khush, 1984). Rice is grown in a much wider range of hydro-logical...

Introduction To Climate And Crop Production

Climate change is expected to have a variety of effects on global temperatures, sea levels and the availability of water in agricultural landscapes. According to the Intergovernmental Panel on Climate Change (IPCC), since 1950 average global surface temperatures have risen by 0.7 C and the sea level has risen by 10 cm. There has also been decreased precipitation in the Sahel, the Mediterranean, southern Africa and parts of southern Asia, and an increased risk of heavy precipitation events over...

Regional climate models RCMs and seasonal forecasting

Aogcm Sres

Assessing future projections of climates driven by the different changes of concentrations of GHGs, anthropogenic activities, natural forces, and other boundary and initial conditions through a GCM requires a large storage and processing capacity and, due to that, temporal and spatial resolutions of GCM outputs are still limited. Agricultural landscapes vary on a small scale and broad resolution results of GCMs do not provide the necessary spatial accuracy in order to assess the likely impacts...

Molecular breeding for drought and heat

In breeding applications, molecular markers may be either diagnostic (i.e. perfect markers of a specific allele within a specific gene sequence) or putative (e.g. markers associated with or flanking a QTL that has been discovered via mapping in biparental crosses or in association panels of related or unrelated lines). Diagnostic markers are preferable as they can be used to select desired alleles in any parental or progeny line of a species under any crossing strategy. Alternatively, such...

Suppressive Soils

A significant body of research has focused on the description and function of soils possessing the capacity to suppress soilborne plant diseases. Disease suppressive soils have been defined as those in which disease development is minimal even in the presence of a virulent pathogen and a susceptible host. The concept of disease suppressive soil has been described in terms of both general suppression and specific suppression. Every natural soil possesses some ability to suppress the activity of...

Factors Leading to Potential Disease and Pest Epidemics

Three essential components are required simultaneously for a disease to occur a virulent pathogen, a susceptible host and a favourable environment. A favourable environment includes all abiotic factors, such as moisture (e.g. air humidity, rainfall and irrigation), temperature, sunlight, wind, nutrition and soil quality, as well as biotic factors, such as beneficial microorganisms and or predators that might interfere with the pathogen or the plant. The relationship between the three essential...

Sea level rise

As temperatures increase, seawater expands in volume and increases in level (thermal expansion). Temperature increases also contribute to glaciers and ice caps melting. The IPCC (2007) estimated that under an intermediate emission scenario (A1B), thermal expansion would produce between 0.3 and 0.8 m of sea level rise by 2300. This is mainly due to the fact that energy moves slowly from the surface to the deep parts of the ocean (IPCC, 2007). Understanding of sea level rises is still limited,...

Genomic Selection a Powerful Tool for Maize Cultivar Adaptation to Climate Change

New genotyping platforms are coming on-stream that will rapidly change the nature of maize cultivar development. These methods have the potential to greatly facilitate the process of developing cultivars adapted to a changing climate, and will increase the importance of 'open-source' multinational testing networks. It is estimated that, within maize breeding programmes, approximately between two and eight haplotypes per gene are present, and that many of these haplotypes recur across breeding...

T 8j XXk aik Y jk 142

Where the constant Xk is the singular value of the kth multiplicative component that is ordered X1> X2> > Xt the aik elements are elements of the kth left singular vector of the true interaction and represent geno-typic sensitivity to hypothetical environmental factors represented by the kth right singular vector with elements Yjk. The aik and yjk elements satisfy the ortho-normalization constraints Xaikak Y,K 0 for k k and Xa2k i XYy 1. When Eqn 14.2 is saturated, the number of bilinear...

Case Studies of Applications of GIS and Modelling to Climate Change

The application of GIS-based systems to agro-climatic analysis under current climate conditions has already been outlined. The availability of a range of GCM outputs run under a suite of emission scenarios is now permitting similar approaches for potential future climates. With any such approaches it should always be borne in mind that outputs from the GCMs are not precise and variation occurs between different models and scenarios. In addition, for agricultural assessments downscaled GCM...

Detecting Crossover Interaction Under Fixed and Mixed Effects Linear Bilinear Models

Can biplot analysis help detect crossover interaction The most important GE in agriculture is COI (Cornelius et al., 1993). In the absence of COI, GE is simply due to differences in scales, and the best genotype in one environment remains the best in all other environments. The usual AMMI2 biplot analysis does not distinguish COIs from non-COIs. A SREG1 biplot based on a constrained singular value decomposition (SVD) non-COI PC1 solution (Crossa and Cornelius, 1997) has been used to predict the...

Conservation Agriculture as a Climate Change Adaptation Strategy

As mentioned earlier, CA improves the soil physical and biological properties. Several of the effects of CA for different systems are summarized in Table 10.1. The resulting improved soil quality and improved nutrient cycling will improve the resilience of crops to adapt to changes in local climate change. The minimal soil disturbance and soil cover will protect the biological component of the soil and help with biological tillage, keeping pests and diseases under control through biological...

Breeding for Tolerance

The improvement of crop performance in saline, waterlogged and inundated environments through conventional breeding programmes has been a challenging pursuit. While significant increases in crop yields were achieved in drought and hot environments during the post-Green Revolution era (Lantican et al., 2003) large areas of land subject to salinity, waterlogging and inundation are still to benefit from such a powerful and sustained research thrust. Genetic progress in breeding for tolerance to...

Conclusion On How Biotechnology Improve Organic Manure

Biotechnology provides a range of new tools and techniques that can provide increased flexibility and efficiency to plant breeders. Some of the most promising targets are described in Table 12.9. Despite climate change, breeders will be able to respond more rapidly to the requirements of cropping systems. Improvements in conventional breeding are already being realized by many programmes through the application of molecular markers, the use of doubled haploids and a greater understanding of...

Wide Adaptation to Buffer Temporal Climatic Variability in Wheat

The impact of CIMMYT's wheat breeding on international collaborative wheat improvement has been discussed by Reynolds and Borlaug (2006). CIMMYT's wheat breeding philosophy and methodology embraces three important principals the development of germplasm with high and stable yield across a wide range of environments. The concept of wide adaptation has been criticized, with local or specific adaptation advocated. However, we believe that wide adaptation to a broad range of environments becomes...

Adapting to Biotic and Abiotic Stresses Through Crop Breeding

One of the most challenging aspects of adapting crops to climate change will be to maintain their genetic resistance to pests and diseases, including weeds, herbivorous insects, arthropods, nematodes, fungi, bacteria and viruses. Rising temperatures and variations in humidity affect the diversity and responsiveness of agricultural pests and diseases and are likely to lead to new and perhaps unpredictable epidemiologies (Gregory et al., 2009). Legreve and Duveiller in Chapter 4 explain that, for...

New Tools for Enhancing Crop Adaptation to Climate Change

The final section of the book presents tools at the 'cutting edge' of agricultural technology. Increased integration of these approaches into breeding programmes is inevitable, at least for those providing unequivocal benefits. Recent advances in genomics research address the multigenic nature of plant abiotic stress adaptation, including the potential of genetic engineering of new traits which are not amenable to conventional breeding (Ortiz, 2008 Federoff et al., 2010). The marriage of...

Mixedeffect Linear Bilinear Models

What if genotypes or environments, or both, are random effects A mixed-model analogue of biplot analysis has been developed using the factor analytic (FA) model for approximating the variance-covariance GE structure (Piepho, 1998 Smith et al., 2002). Research conducted by Crossa et al. (2006) and Burgueno et al. (2008) described how to model variance-covariance GE and GGE using the FA model and how to incorporate the additive (relationship A) matrix and the additive x additive covariance matrix...

Green manure systems to induce biological soil suppressiveness

Green manures have been examined extensively as a means to improve soil quality, but although long studied (Millard and Taylor, 1927 Rouatt and Atkinson, 1950) this practice has been less effective or consistent when applied to a system for the control of soilborne diseases. As with certain organic residue amendments, green manuring may exacerbate disease development if used in concert with an inappropriate pathosystem (Manici et al., 2004). The lack of consistency can be attributed to various...

Supporting conventional breeding

Breeding programmes often grow thousands, or millions, of individual plants to increase the probability of identifying individual plants with specific gene combinations this requires new tools, some biotechnological, for plant selection. Isozyme markers were used in the 1980s to hasten the introgression of monogenic traits from wild germplasm into a cultivated background, a process now known as marker assisted selection (MAS) and now based around the direct detection of variation in DNA...

Genetic Modification or Transgenic Technologies

Genetic modification (GM) involves alteration of an organism's genetic material (DNA or RNA) involving 1. Transferring genes between organisms. 2. Moving, deleting, modifying or multiplying genes within an organism. 4. The incorporation of newly constructed genes into a new organism. Example 18 GM techniques have been used to develop male sterility for use in hybrid breeding, cereals enriched in commercially valuable oils, proteins and starches as well as resistance to herbicides such as...

C sequestration in maize and wheat cropping systems

The global C cycle is constituted by a short-term biochemical cycle superimposed on a long-term geochemical cycle. Annually, anthropogenic activities distort both cycles by emitting 8.6 Pg C, which is absorbed by the atmosphere (3.3 Pg C), the oceans (2.2 Pg C) and unknown sinks (Lal, 2007). The soil C pool comprises two components (i) the soil organic carbon (SOC) pool and (ii) the soil inorganic carbon (SIC) pool. Agricultural activities affect mainly the SOC pool, which constitutes a...

Contributors

Dr Pramod Aggarwal, Indian Agricultural Research Institute, Environmental Sciences, New Delhi-110012, India. E-mail pkaggarwal.iari gmail.com Mr Ben Anderson, International Centre for Tropical Agriculture (CIAT), Cali, Colombia, AA6713 and School for International Service, American University, Washington, DC 20016-8048, USA. E-mail bowenanderson gmail.com Dr Gary Atlin, International Maize and Wheat Improvement Center (CIMMYT), Apdo. Postal 6-641, 06600 Mexico, D.F., Mexico. E-mail g.atlin...

Mitigation of N2O emissions through conservation agriculture

The two main processes of the N cycle that determine the production of N2O are nitrification and denitrification. Denitrification occurs under anaerobic conditions where nitrate is reduced to various N forms as follows Any management practice that creates anaerobic conditions including flooding, especially in heavy textured soils, when nitrate is present will lead to increased N2O emissions (Ball et al., 1999). These emissions can be reduced by aerating the soil, especially in coarse textured...

Mitigation of CH4 through conservation agriculture

Changes in land use, especially cultivation of formerly undisturbed soils, strongly decrease CH4 oxidation and consequently the uptake of atmospheric CH4 by the soil (Hutsch, 1998 Chan and Parkin, 2001). Typically, agricultural soils vary from being minor emitters of CH4 to small sinks for atmospheric CH4 (Chan and Parkin, 2001). Hutsch (1998) suggested that a reduction in tillage intensity could help minimize the adverse effects of cultivation on soil CH4 uptake. But according to Omonode et...

Agricultural practices rotation time of planting and avoidance

In many regions, intensification has replaced diverse agroecosystems and increased the vulnerability to pest attacks. Monoculture and growing 'megacultivars' (varieties occupying millions of hectares, such as the wheat cultivars 'PBW343' and 'Inqualab' in India and Pakistan) increase the likelihood of pathogen recombination or mutation by selection pressure. Changes in seasonal weather patterns could also contribute to the displacement of land use and crop-producing areas (Kiritani, 2007)....

Domestication of halophytes

Dryland soils that have ECe values greater than 8 dS m can be described as being highly salt affected and such soils are generally too saline for major crops to produce commercial yields. The growth of plants for commercial use in these landscapes necessitates the use of halophytes. The case for this is made more compelling by the fact that many halophytes have an increase in growth with some salinity (50-200 mM NaCl) in the root zone (Greenway and Munns, 1980). Current databases list more than...

Breeding approaches

Breeding approaches for improving abiotic stress tolerance in crop species are evolving at a rapid pace. With the development of molecular technologies, transgenic approaches have become a prominent part of many research initiatives. Genetic transformation currently assists in the study of cellular mechanisms underlying salt, waterlogging and inundation tolerance, and there have been many potentially beneficial genes identified for genetic transformation (Dennis et al., 2000 Yamaguchi and...

References Of Crop Production

Amani, I., Fischer, R.A. and Reynolds, M.P (1996) Canopy temperature depression association with yield of irrigated spring wheat cultivars in a hot climate. Journal of Agronomy and Crop Science 176, 119-129. Ammar, K., Lage, J., Villegas, D., Crossa, J., Hernandez, H. and Alvarado, G. (2008) Association among durum wheat international testing sites and trends in yield progress over the last twenty-two years. In Reynolds, M.P, Pietragalla, J. and Braun, H.-J. (eds) International Symposium on...

Impact of Climate Change on Wheat Megaenvironments

CIMMYT develops improved wheat germ-plasm for use in developing and emerging countries, which grow wheat on about 110 million ha (Lantican et al., 2005). To address the needs of these diverse wheat growing areas, CIMMYT uses the concept of megaenvironments (MEs) (Rajaram et al., 1994) to target germplasm development. A ME is defined as a broad, not necessarily contiguous, area occurring in more than one country and frequently transcontinental, defined by similar biotic and abiotic stresses,...

Incorporating External Covariables for Explaining Genotype x Environment Interaction

This section is related to the issue outlined by Yang et al. 2009 , which is how relevant is biplot analysis for understanding the nature and causes of interaction Factorial regression FR or partial least squares PLS analysis e.g. Vargas et al., 1999 van Eeuwijk et al., 2005 is useful for studying the effects of both genetic and environmental covari-ables and to develop functional relationships and predictability with explanatory covari-ables. The structural equation model SEM using endogenous...