Erika C.H. Meng; John P. Brennan

ISBN 978-1-57808-575-0/ October 2009/ 204 pages

Scientific breeding in the twentieth century greatly accelerated wheat’s evolution, producing high-yielding varieties that helped avoid famine in many developing countries. Emerging scientific tools hold promise for identifying and tapping new, useful genetic diversity within wheat’s primary and secondary gene pools and, through genetic engineering, beyond.
The book describes generally how policies affect wheat genetic diversity; it looks at historical changes in wheat genetic diversity, as policy and priorities have evolved; it identifies factors that explain changes and differences in spatial diversity; and finally, it analyzes the productivity impacts of changes in diversity. Chapters define various types of crop genetic diversity and ways to measure them, framing the definitions and metrics in the contexts for which they are most relevant.

Published in Science 327(5967);833-834, 2010

Radically Rethinking Agriculture for the 21st Century

N. V. Fedoroff, D. S. Battisti, R. N. Beachy, P. J. M. Cooper, D. A. Fischhoff, C. N. Hodges, V. C. Knauf, D. Lobell, B. J. Mazur, D. Molden, M. P. Reynolds, P. C. Ronald, M. W. Rosegrant, P. A. Sanchez, A. Vonshak, J.-K. Zhu

Population growth, arable land and fresh water limits, and climate change have profound implications for the ability of agriculture to meet this century’s demands for food, feed, fiber, and fuel while reducing the environmental impact of their production. Success depends on the acceptance and use of contemporary molecular techniques, as well as the increasing development of farming systems that use saline water and integrate nutrient flows.

Published in Functional Plant Biology 37, 166–174, 2010

Stem solidness and its relationship to water-soluble carbohydrates: association with wheat yield under water deficit

Saint Pierre C., Trethowan R., Reynolds M.

A study of 36 wheat (Triticum aestivum L.) genotypes with different levels of stem solidness was conducted to assess the heritability and relationship among stem morphological properties, stem water-soluble carbohydrates (WSC) storage capacity and grain yield. The total amount of pith-fill in the upper stem internode (VOL) was highly correlated with the total content of WSC per stem under both water deficit (DEF) (r = 0.56) and well irrigated conditions (IRR) (r = 0.49). A positive correlation was also found between VOL and grain yield under DEF (r = 0.49), which was explained by the positive contribution of WSC to grain yield. A closer association of grain yield and morphological traits was identified under DEF than under IRR. The closer associations found among estimations of %WSC and WSC-area and grain yield under DEF indicate that these variables may be adaptive rather than constitutive traits. High heritability values (0.77–0.84) observed for stem morphological traits reinforce their potential use in breeding for high WSC and ultimately, higher grain yield under water-limited environments. Stem length, diameter and solidness could be combined in an ideal plant ideotype to maximise WSC reserves as a strategy to improve yield under water-limited conditions.

Published in Plant Disease 94(1):45-53, 2010

Seedling and slow rusting resistance to leaf rust in Chinese wheat cultivars

Li, Z.F.; Xia, X.C.; He, Z.H.; Li, X.; Zhang, L.J.; Wang, H.Y.; Meng, Q.F.; Yang, W.X.; Li, G.Q.; Liu, D.Q.

Identification of resistance genes is important for developing leaf rust resistant wheat (Triticum aestivum) cultivars. A total of 102 Chinese winter wheat cultivars and advanced lines were inoculated with 24 pathotypes of Puccinia triticina for postulation of leaf rust resistance genes effective at the seedling stage. These genotypes were also planted in the field for characterization of slow rusting responses to leaf rust in the 2006–07 and 2007–08 cropping seasons. Fourteen leaf rust resistance genes—Lr1, Lr2a, Lr3bg, Lr3ka, Lr14a, Lr16, Lr17a, Lr18, Lr20, Lr23, Lr24, Lr26, Lr34, and LrZH84—either singly or in combinations, were postulated in 65 genotypes, whereas known resistance genes were not identified in the other 37 accessions. Resistance gene Lr26 was present in 44 accessions. Genes Lr14a and Lr34 were each detected in seven entries. Lr1 and Lr3ka were each found in six cultivars, and five lines possessed Lr16. Lr17a and Lr18 were each identified in four lines. Three cultivars were postulated to possess Lr3bg. Genes Lr20, Lr24, and LrZH84 were each present in two cultivars. Each of the genes Lr2a and Lr23 may exist in one line. Fourteen genotypes showed slow leaf rusting resistance in two cropping seasons.

Published in Applied Geography 30(1):112-125, 2010

Poverty mapping based on livelihood assets: A meso-level application in the Indo-Gangetic Plains, India

Olaf Erenstein, Jon Hellin and Parvesh Chandna

Poverty maps are an increasingly popular mode of visualizing the spatial dimension of poverty. They help guide priority-setting and target poverty-alleviation interventions. The utility of poverty maps can be enhanced by spatially disaggregating the underlying causes of poverty. One promising approach explored in this paper is the use of livelihood assets – natural, physical, human, social and financial – the building blocks of sustainable livelihoods. We illustrate the approach by mapping and contrasting poverty and livelihood assets within the Indian Indo-Gangetic Plains drawing on district-level indicators and livelihood asset-based principal components. The relatively low poverty incidence in the north-western plains is associated with an overall favorable livelihood asset base, particularly pronounced for natural and financial capitals. There is a marked gradient with poverty increasing eastwards, reflecting a similarly marked decline in livelihood assets. The overall unfavorable livelihood asset base in the mid-Gangetic Plains of Bihar and Eastern Uttar Pradesh provides a particularly challenging spatial poverty trap. The maps and regional contrasts of poverty and livelihood assets provide a foundation for future research and development work and reiterate the need for cross-sectoral and inter-disciplinary approaches.

Published in Euphytica 171(1): 23-38, 2010

Phenotypic correlations, G × E interactions and broad sense heritability analysis of grain and flour quality characteristics in high latitude spring bread wheats from Kazakhstan and Siberia

Hugo Ferney Gómez-Becerra, Aigul Abugalieva, Alexei Morgounov, K. Abdullayev, L. Bekenova, M. Yessimbekova, G. Sereda, S. Shpigun, V. Tsygankov, Yu Zelenskiy, Roberto Javier Peña and Ismail Cakmak

Grain and flour samples of 42 high latitude spring bread wheat genotypes from Kazakhstan and Siberia evaluated in a multi-location trial were analyzed for grain concentrations of protein, zinc (Zn) and iron (Fe), as well as flour quality characteristics. The genotypes showed high grain protein concentrations (14–19%), but low dough strength was a common feature for most of them. Significant positive correlations were found between grain protein and flour protein, gluten, gliadin, gli/glu ratio, Zn, and Fe contents. Grain protein was also correlated positively with hardness, sedimentation, farinograph dough development time (DDT), stability time and ash content. Grain Fe concentration was positively associated with sedimentation, stability time, water absorption and valorimeter value, suggesting that improvements in micronutrient concentrations in the grain parallels enhancement in gluten strength. Interestingly, glutenin content correlated negatively with the concentrations of grain and flour protein, gluten, and minerals; and also with gluten deformation index (IDK), DDT, and stability time. Conversely, gliadin content showed strong positive correlations with the concentrations of grain and flour protein, gluten, and minerals. Gliadin also correlated positively, but in lesser magnitude, with DDT, stability time and IDK. Environment and G×E interaction were important sources of variation for some quality characteristics. This was reflected in the low broad sense heritability (H) values for traits related to flour strength, such as sedimentation, IDK, stability time and gliadin content. Breeding strategies, including three testing locations at the advanced selection stages, are adequate for the enhancement of most of the quality traits, but faster improvement in flour strength could be achieved with a larger number of locations.

Published in Food Policy 35(1):41-50, 2010

Mapping natural resource-based poverty, with an application to rural Syria.

Judit Szonyi, Eddy De Pauw, Roberto La Rovere and Aden Aw-Hassan

This study presents advances in resource-based poverty mapping. It illustrates how agricultural income distribution maps can be generated at small pixel-level, providing an application of the approach in rural Syria. Census data on agriculture and population are disaggregated based on pixel-level agricultural productivity coefficients derived in a GIS environment. The approach, triangulated with survey results and compared with sub-national poverty maps, shows that the better-income areas of Syria are located in the irrigated and higher-rainfall areas, though lower-income pockets exist due to the presence of ecological and topographic factors or due to high population density. The method can be used for developing high-resolution, low cost maps for rapid detection of resource-driven poverty in low income countries where agriculture is a major source of rural income, and where poverty mapping is rarely undertaken due to the high costs involved.

Published in Euphytica 171(1): 53-64, 2010

Identifying high yielding stable winter wheat genotypes for irrigated environments in Central and West Asia

Ram C. Sharma, Alexei I. Morgounov, Hans J. Braun, Beyhan Akin, Mesut Keser, David Bedoshvili, Ahmet Bagci, Christopher Martius and Maarten van Ginkel

Improved winter wheat (Triticum aestivum L.) cultivars are needed for the diverse environments in Central and West Asia to improve rural livelihoods. This study was conducted to determine the performance of elite winter wheat breeding lines developed by the International Winter Wheat Improvement Program (IWWIP), to analyze their stability across diverse environments, and to identify superior genotypes that could be valuable for winter wheat improvement or varietal release. One hundred and one advanced winter wheat breeding lines and four check cultivars were tested over a 5-year period (2004–2008). Grain yield and agronomic traits were analyzed. Stability and genotypic superiority for grain yield were determined using genotype and genotype × environment (GGE) biplot analysis. The experimental genotypes showed high levels of grain yield in each year, with mean values ranging from 3.9 to 6.7 t ha⁻¹. A set of 25 experimental genotypes was identified. These were either equal or superior to the best check based on their high mean yield and stability across environments as assessed by the GGE biplot analysis. The more stable high yielding genotypes were ID800994.W/Falke, Agri/Nac//Attila, ID800994W/Vee//F900K/3/Pony/Opata, AU//YT542/N10B/3/II8260/4/JI/Hys/5/Yunnat Esskiy/6/KS82W409/Spn and F130-L-1-12/MV12. The superior genotypes also had acceptable maturity, plant height and 1,000-kernel weight. Among the superior lines, Agri/Nac//Attila and Shark/F4105W2.1 have already been proposed for release in Kyrgyzstan and Georgia, respectively. The findings provide information on wide adaptation of the internationally important winter wheat genotypes, and demonstrate that the IWWIP program is enriching the germplasm base in the region with superior winter wheat genotypes to the benefit of national and international winter wheat improvement programs.

Published in World Development 38(1):64-75, 2010

How Cost-Effective is Biofortification in Combating Micronutrient Malnutrition? An Ex ante Assessment

J.V. Meenakshi, Nancy L. Johnson, Victor M. Manyong, Hugo DeGroote, Josyline Javelosa, David R. Yanggen, Firdousi Naher, Carolina Gonzalez, James García and Erika Meng

Biofortification is increasingly seen as an additional tool to combat micronutrient malnutrition. This paper estimates the costs and potential benefits of biofortification of globally important staple food crops with provitamin A, iron, and zinc for twelve countries in Africa, Asia, and Latin America. Using a modification of the Disability-Adjusted Life Years framework we conclude that overall, the intervention can make a significant impact on the burden of micronutrient deficiencies in the developing world in a highly cost-effective manner. Results differ by crop, micronutrient, and country; and major reasons underlying these differences are identified to inform policy.

Published in Crop Science 50(1):105-117, 2010

Hierarchical Multiple-Factor Analysis for Classifying Genotypes Based on Phenotypic and Genetic Data

Jorge Franco, José Crossa and Santosh Desphande

A numerical classification problem encountered by breeders and gene-bank curators is how to partition the original heterogeneous population of genotypes into non-overlapping homogeneous subpopulations. The measure of distance that may be defined depends on the type of variables measured (i.e., continuous and/or discrete). The key points are whether and how a distance may be defined using all types of variables to achieve effective classification. The objective of this research was to propose an approach that combines the use of hierarchical multiple-factor analysis (HMFA) and the two-stage Ward Modified Location Model (Ward-MLM) classification strategy that allows (i) combining different types of phenotypic and genetic data simultaneously; (ii) balancing out the effects of the different phenotypic, genetic, continuous, and discrete variables; and (iii) measuring the contribution of each original variable to the new principal axes (PAs). Of the two strategies applied for developing PA scores to be used for clustering genotypes, the strategy that used the first few PA scores to which phenotypic and genetic variables each contributed 50% (i.e., a balanced contribution) formed better groups than those formed by the strategy that used a large number of PA scores explaining 95% of total variability. Phenotypic variables account for much variability in the initial PA; then their contributions decrease. The importance of genetic variables increases in later PAs. Results showed that various phenotypic and genetic variables made important contributions to the new PA. The HMFA uses all phenotypic and genetic variables simultaneously and, in conjunction with the Ward-MLM method, it offers an effective unifying approach for the classification of breeding genotypes into homogeneous groups and for the formation of core subsets for genetic resource conservation.