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...

References

Atlin, G.N., Baker, R.J., Lu, X. and McRae, K.B. (2000) Selection response in subdivided target regions. Crop Science 40, 7-13. Atlin, G.N., Lafitte, H.R., Tao, D., Laza, M., Amante, M. and Courtois, B. (2006) Developing rice cultivars for high-fertility upland systems in the Asian tropics. Field Crops Research 97, 43-52. Banziger, M., Betran, F.J. and Lafitte, H.R. (1997) The efficiency of high nitrogen selection environments for improving maize for low-nitrogen target environments. Crop...

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...

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...