CIAT Articles in Journals

Permanent URI for this collectionhttps://hdl.handle.net/10568/35700

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Modernization of a peasant crop in Colombia: Evidence and implications
(Journal Article, 1994-01) Janssen, Willem G.; Londooo, N. Ruiz de
Susceptibility of common weeds and cultivated crops in major maize growing agroecological zones of Uganda to viruses causing maize lethal necrosis disease
(Journal Article, 2019-10-19) Mudde, B.; Miano D.W.; Olubayo, F.M.; Asea, G.; Kilalo, D.C.; Kwemoi, D.B.; Adriko, J.; Ssekiwoko, F.; Male, A.; Kiggundu, A.
Maize lethal necrosis (MLN) disease is caused when maize plants become co-infected with Maize chlorotic mottle virus (MCMV) and potyviruses notably Sugarcane Mosaic Virus (SCMV). Apart from maize, little is known about susceptibility of weed species and cultivated crop species usually growing in proximity with maize to MLN viruses in Uganda. The common weeds and crop plants were mechanically inoculated with combined sap from MCMV and SCMV infected maize plants. Samples were tested for MLN causing viruses by Double Antibody Sandwich Enzyme-Linked Immunosorbent Assay (DAS-ELISA) and Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). The weeds that were susceptible to MCMV were Digitaria abyssinica, Eleusine africana and Roetboellia cochinchinensis; while those susceptible to SCMV were Pennisetum purpureum, Panicum maximum and Roetboellia cochinchinensis. The cultivated crops were susceptible only to MCMV and included cassava (Manihot esculenta), groundnut (Arachis hypogaea) and bean (Phaseolus vulgaris). Common weeds and cultivated crops growing close to maize in Uganda have differential susceptibility to MLN causing viruses and can act as reservoirs of MLN causing viruses. It is critical to identify non-MLN hosts in cultivated crops for crop rotation and early weeding to reduce on MLN virus inoculum in cropping system
DNA extraction from silica gel-preserved common bean (Phaseolus vulgaris L.) leaves
(Journal Article, 2018-11-08) Ssekamate, Allan Male; Kato, Fred; Mukankusi, Clare
Extraction of non-degraded and contaminant-free DNA from field specimen requires collection under liquid nitrogen which is not readily available in resource constrained laboratories in low and middle income countries (LMICs). A method of extracting DNA from silica gel-preserved common bean (Proteus vulgaris L.) leaves is presented. The method, which does not involve the use of phenol, chloroform or isoamyl alcohol also obviates the need for low temperature incubation during the DNA extraction steps and the grinding of desiccated leaf tissue in liquid nitrogen. It relies on inactivating proteins using SDS and proteinase K along with precipitation of polysaccharides using a high salt solution (0.8 M NaCl). DNA is further purified by exploiting its insolubility in aqueous media. High quality pure DNA (mean concentration 2.84 ± 0.013 µg/g of dry leaf tissue) with mean DNA purity values of 2.1 ± 0.1 was extracted. The DNA was also found to be free of protein and polysaccharide contamination. This method enables DNA amplification using molecular markers routinely used in molecular biology laboratories like random amplified polymorphic (RAPD) markers, inter simple sequence repeat (ISSR) markers, sequence-characterized amplified region (SCAR) markers and simple sequence repeat (SSR) markers. The findings of this study show that it is possible to obtain high quality DNA from leaf tissue preserved in silica gel. The method used in this research will be invaluable to resource constrained laboratories in low and middle income countries (LMICs) that cannot afford to buy or access liquid nitrogen in order to extract high quality DNA and for research groups undertaking field surveys that require several days or weeks off station without laboratory freezers to maintain the integrity of the tissues which is crucial for obtaining high quality DNA.
Returns to food and agricultural R&D investments in Sub-Saharan Africa, 1975–2014
(Journal Article, 2016-12) Pardey, Philip G.; Andrade, Robert Santiago; Hurley, Terrance; Rao, Xudong; Liebenberg, Frikkie
Research-enabled growth in agricultural productivity is pivotal to sub-Saharan Africa's overall economic growth prospects. Yet, investments in research and development (R&D) targeted to many national food and agricultural economies throughout Africa are fragile and faltering. To gain insight into what could be driving this trend, this article updates, summarizes and reassesses the published evidence on the returns to African agricultural R&D. Based on a compilation of 113 studies published between 1975 and 2014 spanning 25 countries, the reported internal rates of return (IRRs) to food and agricultural research conducted in or of direct consequence for sub-Saharan Africa averaged 42.3%py. In addition to the 376 IRR estimates, the corresponding 129 benefit-cost ratios (BCRs) averaged 30.1. Most (96.5%) of the returns-to-research evaluations are of publicly performed R&D, and the majority (87.6%) of the studies were published in the period 1990-2009. The large dispersion in the reported IRRs and BCRs makes it difficult to discern meaningful patterns in the evidence. Moreover, the distribution of IRRs is heavily (positively) skewed, such that the median value (35.0%py) is well below the mean, like it is for research done elsewhere in the world (mean 62.4%py; median 38.0%py). Around 78.5% of the evaluations relate to the commodity-specific consequences of agricultural research, while 5.5% report on the returns to an "all agriculture" aggregate. The weight of commodity-specific evaluation evidence is not especially congruent with the composition of agricultural production throughout Africa, nor, to the best that can be determined, the commodity orientation of public African agricultural R&D.
Carotenoid crystal formation in Arabidopsis and carrot roots caused by increased phytoene synthase protein levels
(Journal Article, 2009-07-28) Maass, Dirk; Arango, Jacobo; Wüst, Florian; Beyer, Peter; Welsch, Ralf
As the first pathway-specific enzyme in carotenoid biosynthesis, phytoene synthase (PSY) is a prime regulatory target. This includes a number of biotechnological approaches that have successfully increased the carotenoid content in agronomically relevant non-green plant tissues through tissue-specific PSY overexpression. We investigated the differential effects of constitutive AtPSY overexpression in green and non-green cells of transgenic Arabidopsis lines. This revealed striking similarities to the situation found in orange carrot roots with respect to carotenoid amounts and sequestration mechanism.
Molecular mechanisms of carotenoid accumulation in carrots
(Journal Article, 2017-03) Welsch, Ralf; Arango, Jacobo; Beyer, Peter; Jourdan, Matthieu; Geoffriau, Emmanuel
Orange carrots are the example par excellence for extraordinary high and accumulation of carotenoids. In contrast to other carotenoid-accumulating systems, knowledge on the molecular mechanisms involved is rather sparse. The first enzyme of the carotenoid pathway, phytoene synthase (PSY), frequently determines carotenoid amounts in many other tissues, and we thus investigated its contribution to carotenoid accumulation in carrots. Overexpression of PSY in white-rooted carrots resulted in the accumulation of β-carotene as crystals. This confirmed that increased phytoene synthesis is sufficient to achieve β-carotene concentrations high enough to result in the formation of crystals. In agreement with this, PSY protein amounts were high in orange but almost absent in white-rooted carrot cultivars. However, this contrasted with only slightly different PSY expression levels comparing white and orange carrots and suggests additional mechanisms acting beyond transcription. In fact, we found a negative feedback regulation emerging from xanthophyll-derived metabolites which modulate PSY protein levels. This was shown by the overexpression of the carotene hydroxylase CYP97A3 from Arabidopsis in orange carrots. These lines showed strongly reduced α-carotene levels through its enhanced CYP97A3-catalyzed hydroxylation, but also lower PSY protein levels which accordingly resulted in lower total carotenoid amounts. In agreement with these findings, we identified an 8 nt frame shift insertion in a carrot CYP97A3 hydroxylase allele encoding a truncated and thus non-functional enzyme. The corresponding polymorphism was significantly associated with high α-carotene levels and high α-/β- carotene ratios determined in a large association mapping analysis and explained a large proportion of the variation in carrots. Our results emphasize the rate-limiting role for PSY in carotenoid biosynthesis and show that previously unknown regulatory mechanisms determine carotenoid accumulation in orange carrots.
Rheological and textural properties of lafun, a stiff dough, from improved cassava varieties
(Journal Article, 2021-03) Bouniol, Alexandre; Adinsi, Laurent; Padonou, Sègla Wilfrid; Hotegni, Francis; Gnanvossou, Désiré; Tran, Thierry; Dufour, Dominique; Joseph, Djidjoho; Akissoé, Hounhouigan Noël
We studied the textural and rheological (viscoelastic) properties of fresh lafun dough, a fermented cassava product, and their changes during storage at 45 °C for 5 and 24 h, in order to determine after‐cooking storability. Lafun flours were produced from three types of cassava varieties: seven improved white‐fleshed varieties, seven improved provitamin A carotenoids (pVAC) varieties and two local white‐fleshed varieties; and processed into lafun doughs. Pasting properties of the flours were assessed. Flours from local varieties had pasting profiles with highest viscosities, while pVAC flours had the lowest. The three types of cassava varieties varied significantly in most of their pasting properties. Four promising improved varieties were identified, based on high peak viscosity (55.8–61.5 P) and stiffer texture than local varieties during storage. Undesirable varieties were also found, which softened during storage instead of hardening. Optimum texture of lafun dough was obtained after 5 h of storage.
Cost and benefit analysis of adopting climate adaptation practices among smallholders: The case of five selected practices in Ghana
(Journal Article, 2020-12) Williams, Portia Adade; Karanja Ng'ang'a, Stanley; Crespo, Olivier; Abu, Mumuni
Smallholder farmers mostly depend on agriculture for their sustenance yet the sector is threatened by changing climate. It is essential for smallholders to adapt to reduce their vulnerability. Estimating the economic effectiveness of climate adaptation practices would enhance planning and actions among stakeholders and consequently impact policy. This study conducted an ex-ante in-depth empirical analysis of the costs and benefits of implementing five climate adaptation strategies identified among smallholder horticultural farmers in Ghana. A total of 180 smallholder households who have implemented the identified practices in two horticultural cropgrowing municipalities were surveyed. Profitability indicators, evaluation of environmental and social externalities were employed to comparatively estimate the cost-effectiveness of the practices. The results indicated that, from private and public perspectives, implementing any of the five adaptation practices would yield positive benefits. However, considering the capital required, payback period for investments made and risks from implementation, two out of the five practices are particularly fitting choices for the smallholders. Institutional and policy support is desirable if all the practices are to be adopted. To broaden information on potential of climate adaptation vis-a-vis ` climatic effects with economic analysis, the study proposes integrating localized climate vulnerability and economic assessments for enhanced climate adaptation actions.
A review of cassava semolina (gari and eba) end‐user preferences and implications for varietal trait evaluation
(Journal Article, 2021-03) Awoyale, Wasiu; Oladeji, Emmanuel; Chijioke, Alamu Ugo; Tran, Thierry; Noel, Hubert; Tchuente, Takam; Ndjouenkeu, Robert; Kegah, Ngoualem; Maziya‐Dixon, Busie
The purpose of this review is to support breeders and food scientists by examining research carried out on end-user preferences for gari and its derived dough product, eba, in Africa. The review focused on gari regarding the physical and chemical composition of raw cassava roots, methods of storage, the composition of gari with or without enrichment, and the sensory evaluation of gari and eba. The primary sensory attributes identified to describe gari are colour, taste, texture, aroma and flavour. Texture attribute of importance is crispiness for uncooked gari, and hand feel before consumption for eba. There was a significant correlation between the sensory characteristics of gari and the starch and cyanogenic potential (CNP) contents of the raw roots. Hence, the correlation of the end-user preferences with the chemical composition of the cassava roots could be helpful to breeders in refining selection criteria and developing high-throughput screening methods.
Identification of critical versus robust processing unit operations determining the physical and biochemical properties of cassava‐based semolina (gari)
(Journal Article, 2021-03) Escobar, Andrés; Rondet, Eric; Dahdouh, Layal; Ricci, Julien; Akissoé, Noël; Dufour, Dominique; Tran, Thierry; Cuq, Bernard; Delalonde, Michèle
The gari‐making process involves several unit operations (U.O.), some of which strongly influence the quality of the end product. Two contrasting process scales (laboratory‐scale vs conventional) were compared in order to identify which U.O. were affected by the change of scale. U.O. that changed end‐product characteristics depending on process scale were deemed critical; whereas U.O. that resulted in similar characteristics were deemed robust. The classification depended on quality attributes considered: rasping and roasting were critical for physical properties, in particular particle size which ranged from 0.44 to 0.89 mm between the two process scales; and robust for biochemical properties. In contrast, fermentation and pressing were critical for biochemical properties such as lactic acid content (0.93–1.88 g/100 g dry matter after pressing), which influences the perception of flavour, and robust for physical properties. This classification between critical and robust operations help quality control of gari, by pinpointing which U.O. control specific quality characteristics.
Ex ante mapping of favorable zones for uptake of climate-smart agricultural practices: A case study in West Africa
(Journal Article, 2021-03) Andrieu, Nadine; Dumas, Patrice; Hemmerlé, Emma; Caforio, Francesca; Falconnier, Gatien N.; Blanchard, Mélanie; Vayssières, Jonathan
Towards low carbon agriculture: Systematic-narratives of climate-smart agriculture mitigation potential in Africa
(Journal Article, 2020-12) Weniga Anuga, Samuel; Chirinda, Ngonidzashe; Nukpezah, Daniel; Ahenkan, Albert; Andrieu, Nadine; Gordon, Christopher
The agricultural sector is the second major source of climate change globally, contributing to anthropogenic Greenhouse Gas (GHG) emissions. In low-to-middle income countries, estimations indicate future increases in agricultural emissions. Climate-Smart Agriculture (CSA) has an express opportunity to transform agriculture across the globe. In Africa, CSA targets focused on resilience building and food security with less emphasis on the GHG mitigation potential. Nevertheless, to make CSA conclusive as an express low emission development strategy in Africa, understanding the mitigation potential in this context is paramount. Through a systematic-narrative review approach conducted on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses), the study aimed to identify opportunities to mitigate GHG emissions in Africa. We observed that the distribution of studies that quantitatively assessed the GHG emissions of CSA practices was disproportionate across Africa. For instance, out of twenty studies evaluated, nine were conducted in Southern Africa; three in East Africa, and the rest distributed among Central, Western, and North Africa. Observed in the studies, advanced livestock breeding and feeding, organic nitrogen input, improved pastures and switching land-use practices, all contributed to GHG emission reduction. As limited experimental evidence exist on the GHG mitigation potential for some of the CSA alternatives including agroforestry, rotational farming, improved livestock breed and intensification of ruminants' diet, we recommend further experimental studies into these alternatives in more locations/contexts in Africa. Also, progress on the mitigation pillar is still limited in Africa due to lack of the necessary analytical infrastructure to conduct the needed measurements. We call for urgent investments into laboratory facilities and skills training to improve data collection and quality.
Can we turn the tide? Confronting gender inequality in climate policy
(Journal Article, 2020-09-01) Huyer, Sophia; Acosta, Mariola; Gumucio, Tatiana; Ilham, Jasmin Irisha Jim
Emerging global crises such as climate change, massive migrations, pandemics, and environmental degradation are posing serious risks to humanity, threatening ecosystems and rural livelihoods across the globe. The poor, and especially the most marginalised among the poor, are disproportionately affected. Climate change in particular is expected to exacerbate pre-existing social inequalities, including gender inequalities. Therefore, innovative and equitable climate adaptation and mitigation strategies will be needed. This article reviews the progress so far in integrating a gender perspective into climate change policy discussions and agreements at global and national levels.
Fusarium wilt of banana, a recurring threat to global banana production
(Journal Article, 2020-12) Drenth, Andre; Kema, Gert; Dita Rodriguez, Miguel Angel; Jansen, Kees; Vellema, Sietze R.; Stoorvogel, Jetse
TR4 first emerged in Southeast Asia (Ploetz, 1990) and its current rapid spread was analysed by Ordóñez et al. (2015). Subsequent studies showed that the TR4 strain is extremely virulent towards many banana cultivars, including Cavendish cultivars grown in large-scale monoculture plantations for export markets and many banana varieties important for food security and domestic consumption. There are no readily available solutions to manage this disease. Moreover, this global threat connects export trade, strongly dependent on the susceptible Cavendish cultivars, to local production systems wherein a range of banana varieties contributing to food security are also impacted.This research topic aims to provide a platform for information exchange and knowledge sharing. The contributions demonstrate an active research community in search of effective control of FWB. Taken together, the papers provide an overview of our current understanding of the biology and epidemiology of TR4, its management and how integrated and innovative solutions are required and need to be embraced by all stakeholders in an effort to build a sustainable banana industry for the future.
Support indigenous food system biocultural diversity
(Journal Article, 2020-12) Argumedo, Alejandro; Song, Yiching; Khoury, Colin K.; Hunter, Danny; Dempewolf, Hannes
The Comment by Carol Zavaleta-Cortijo and colleagues1 was timely in emphasising the challenges faced by Indigenous peoples due to the combined effects of climate change, COVID-19, and longstanding inequities. Although pressure on Indigenous livelihoods is nothing new, current effects are extreme, both in terms of deaths due to the virus and disruptions to lifeways, including Indigenous food systems. Both the importance and also the vulnerability of Indigenous food systems, and therefore the obligation to “ensure that current decisions and development trajectories do not further jeopardise the resilience of Indigenous food systems, which have integral roles in the response of Indigenous populations to current and future pandemics and climatic changes”,1 should be highlighted in all pertinent policy and development arenas, including the Convention on Biological Diversity's Post-2020 Global Biodiversity Framework and upcoming UN Food Systems Summit, among many others. Our experiences in the Andean, Himalayan, and other mountainous regions offer the insight that Indigenous food system biocultural diversity provides the foundations for resilience. This diversity encompasses not only the many crop and livestock species, and their varieties and breeds, but also the wild organisms supporting and interacting with Indigenous agriculture and food. Traditional knowledge systems around this diversity provide health and sustainability solutions that are unique to place, but whose benefits are urgently needed globally.2, 3 The ongoing loss of this biocultural diversity and associated knowledge is a global tragedy. We draw hope from two ongoing movements regarding Indigenous food system biocultural diversity. First, Indigenous communities have organised around nurturing this diversity by sharing experiences and visions on food, health, climate adaptation, conservation, and livelihood generation with others facing similar threats around the world, through networks such as the International Network of Mountain Indigenous Peoples. Second, Indigenous communities are finding ways to engage on their own terms with national and international organisations and institutions about shared interests, on the basis of respect for Indigenous food system diversity and knowledge systems.4 In the aftermath of COVID-19 and ongoing efforts to adapt to and mitigate climate change, we heartily agree with Zavaleta-Cortijo and colleagues that food systems are essential to health and resilience in Indigenous communities. Moreover, as these biocultural processes embody the longest ongoing human experiences with the provision of food under environmental stresses, shocks, and extremes, we suggest that the world has much to learn from Indigenous food systems. Now, more than ever, what is needed is respect for diversity and for the knowledge systems that have both nurtured it and survived because of it.
Survey data on income, food security, and dietary behavior among women and children from households of differing socio-economic status in urban and peri-urban areas of Nairobi, Kenya
(Journal Article, 2020-12) Nyakundi, Fridah N.; Mutua, Mercy M.; Lung'aho, Mercy G.; Chege, Christine G. Kiria; Ndung'u, John; Nungo, Rhoda; Karanja, David
This article describes data collected to analyze consumer behaviors in vulnerable populations by examining key access constraints to nutritious foods among households of differing socio-economic status in urban and peri‑urban areas of Nairobi, Kenya. The key variables studied include wealth status, food security, and dietary behavior indicators at individual and household level. Household food insecurity access scale (HFIAS), livelihood coping strategies (LCS), food expenditure share (FES), food consumption score (FCS), household dietary diversity score (HDDS), minimum dietary diversity-women(MDD-W), and child dietary diversity score (CDDS) indicators were used to measure food security. Household assets were used to develop an asset-based wealth index that grouped the study sample population into five wealth quantiles, while income levels were used to estimate FES. The hypothesis that guided the cross-sectional survey conducted to generate these data is that vulnerability to food insecurity and poverty are important drivers of food choice that influence household and individual dietary behavior. Data from this study was thus used to assess direction and strength of association between; household food insecurity, wealth status, women, children, and household dietary behavior in both urban and peri‑urban populations sampled.
Genomic prediction of agronomic traits in common bean (Phaseolus vulgaris L.) under environmental stress
(Journal Article, 2020-11) Keller, Beat; Ariza-Suárez, Daniel; Hoz, Juan Fernando de la; Aparicio, Johan Steven; Portilla, Benavides Ana Elisabeth; Buendia, Hector Fabio; Mayor, Victor Manuel; Studer, Bruno; Raatz, Bodo
In plant and animal breeding, genomic prediction models are established to select new lines based on genomic data, without the need for laborious phenotyping. Prediction models can be trained on recent or historic phenotypic data and increasingly available genotypic data. This enables the adoption of genomic selection also in under-used legume crops such as common bean. Beans are an important staple food in the tropics and mainly grown by smallholders under limiting environmental conditions such as drought or low soil fertility. Therefore, genotype-by-environment interactions (G × E) are an important consideration when developing new bean varieties. However, G × E are often not considered in genomic prediction models nor are these models implemented in current bean breeding programs. Here we show the prediction abilities of four agronomic traits in common bean under various environmental stresses based on twelve field trials. The dataset includes 481 elite breeding lines characterized by 5,820 SNP markers. Prediction abilities over all twelve trials ranged between 0.6 and 0.8 for yield and days to maturity, respectively, predicting new lines into new seasons. In all four evaluated traits, the prediction abilities reached about 50–80% of the maximum accuracies given by phenotypic correlations and heritability. Predictions under drought and low phosphorus stress were up to 10 and 20% improved when G × E were included in the model, respectively. Our results demonstrate the potential of genomic selection to increase the genetic gain in common bean breeding. Prediction abilities improved when more phenotypic data was available and G × E could be accounted for. Furthermore, the developed models allowed us to predict genotypic performance under different environmental stresses. This will be a key factor in the development of common bean varieties adapted to future challenging conditions.
Towards environmentally sound intensification pathways for dairy development in the Tanga region of Tanzania
(Journal Article, 2020-12) Notenbaert, An Maria Omer; Groot, Jeroen C.J.; Herrero, Mario; Birnholz, Celine A.; Paul, Birthe K.; Pfeifer, Catherine; Fraval, Simon; Lannerstad, Mats; McFadzean, Jamie N.; Dungait, Jennifer A.J.; Morris, Joanne; Ran, Ylva; Barron, Jennie; Tittonell, Pablo A.
The gap between milk demand and domestic supply in Tanzania is large and projected to widen. Meeting such demand through local production of affordable milk presents an opportunity to improve the welfare of producers and market agents through the income and employment generated along the value chain (VC). Efforts to maximize milk yields, production and profitability need to be balanced with long-termsustainability. We combined environmental and economic ex-ante impact assessments of four intervention scenarios for two production systems in the Tanzanian dairy VC using the CLEANED model and an economic feasibility analysis. Intervention scenarios propose increases in milk production through (i) animal genetic improvement, (ii) improved feed, (iii) improved animal health and (iv) a package combining all interventions. Results show that economically feasible farm-level productivity increases of up to 140% go hand-in-hand with increased resource-use efficiency and up to 50% reduction in greenhouse gas (GHG) emission intensities. Absolute increases in water, land and nitrogen requirements in mixed crop-livestock systems call for careful management of stocks and quality of these resources. An overall rise in GHG emissions is expected, with a maximum of 53% increase associated with an 89% increase in milk supply at VC level. The CLEANED tool proved effective to evaluate livestock interventions that improve incomes and food security with minimal environmental footprint. Here, our simulations suggest that due to current low productivity, the greatest efficiency gains in combination with relatively low increases in total GHG emissions can be made in the extensive agro-pastoral dairy systems, which represent the majority of herds.
Genetic mapping for agronomic traits in a MAGIC population of common bean (Phaseolus vulgaris L.) under drought conditions
(Journal Article, 2020-12) Díaz, Santiago; Ariza-Suárez, Daniel; Izquierdo, Paulo; Lobaton, Juan David; Hoz, Juan Fernando de la; Acevedo, Fernando; Duitama, Jorge; Guerrero, Alberto F.; Cajiao V., César Hernando; Mayor, Victor; Beebe, Stephen E.; Raatz, Bodo
Background Common bean is an important staple crop in the tropics of Africa, Asia and the Americas. Particularly smallholder farmers rely on bean as a source for calories, protein and micronutrients. Drought is a major production constraint for common bean, a situation that will be aggravated with current climate change scenarios. In this context, new tools designed to understand the genetic basis governing the phenotypic responses to abiotic stress are required to improve transfer of desirable traits into cultivated beans. Results A multiparent advanced generation intercross (MAGIC) population of common bean was generated from eight Mesoamerican breeding lines representing the phenotypic and genotypic diversity of the CIAT Mesoamerican breeding program. This population was assessed under drought conditions in two field trials for yield, 100 seed weight, iron and zinc accumulation, phenology and pod harvest index. Transgressive segregation was observed for most of these traits. Yield was positively correlated with yield components and pod harvest index (PHI), and negative correlations were found with phenology traits and micromineral contents. Founder haplotypes in the population were identified using Genotyping by Sequencing (GBS). No major population structure was observed in the population. Whole Genome Sequencing (WGS) data from the founder lines was used to impute genotyping data for GWAS. Genetic mapping was carried out with two methods, using association mapping with GWAS, and linkage mapping with haplotype-based interval screening. Thirteen high confidence QTL were identified using both methods and several QTL hotspots were found controlling multiple traits. A major QTL hotspot located on chromosome Pv01 for phenology traits and yield was identified. Further hotspots affecting several traits were observed on chromosomes Pv03 and Pv08. A major QTL for seed Fe content was contributed by MIB778, the founder line with highest micromineral accumulation. Based on imputed WGS data, candidate genes are reported for the identified major QTL, and sequence changes were identified that could cause the phenotypic variation. Conclusions This work demonstrates the importance of this common bean MAGIC population for genetic mapping of agronomic traits, to identify trait associations for molecular breeding tool design and as a new genetic resource for the bean research community.
The influence of household refrigerator ownership on diets in Vietnam
(Journal Article, 2020-12) Heard, Brent R.; Huong, Trinh Thi; Burra, Dharani Dhar; Heller, Martin C.; Miller, Shelie A.; Duong, Than Thi; Simioni, Michel; Jones, Andrew D.

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