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Efficacy of Event MON 87460 in drought-tolerant maize hybrids under optimal and managed drought-stress in Eastern and Southern Africa
No full textBackground: Frequent drought events due to climate change have become a major threat to maize (Zea mays L.) production and food security in Africa. Genetic engineering is one of the ways of improving drought tolerance through gene introgression to reduce the impact of drought stress in maize production. This study aimed to evaluate the efficacy of Event MON 87460 (CspB; DroughtGard®) gene in more than 120 conventional drought-tolerant maize hybrids in Kenya, South Africa, and Uganda for 3–6 years under managed drought-stress and optimal conditions and establish any additional yield contribution or yield penalties of the gene in traited hybrids relative to their non-traited isohybrids. Germplasm used in the study were either MON 87460 traited un-adapted (2008–2010), adapted traited DroughtTEGO® (2011–2013) or a mix of both under confined field trials. Results: Results showed significant yield differences (p < 0.001) among MON 87460 traited and non-traited hybrids across well-watered and managed drought-stress treatments. The gene had positive and significant effect on yield by 36–62% in three hybrids (CML312/CML445; WMA8101/CML445; and CML312/S0125Z) relative to non-traited hybrids under drought, and without significant yield penalty under optimum-moisture conditions in Lutzville, South Africa. Five traited hybrids (WMA2003/WMB4401; CML442/WMB4401; CML489/WMB4401; CML511/CML445; and CML395/WMB4401) had 7–13% significantly higher yield than the non-traited isohybrids out of 34 adapted DroughtTEGO® hybrids with same background genetics in the three countries for ≥ 3 years. The positive effect of MON 87460 was mostly observed under high drought-stress relative to low, moderate, or severe stress levels. Conclusion: This study showed that MON 87460 transgenic drought tolerant maize hybrids could effectively tolerate drought and shield farmers against severe yield loss due to drought stress. The study signified that development and adoption of transgenic drought tolerant maize hybrids can cushion against farm yield losses due to drought stress as part of an integrated approach in adaptation to climate change effects
Post-intervention outcomes in farmers behaviour and crop diversification in Rangpur, Bangladesh
No full textCrop production is highly rice-centric in Bangladesh and, although economically rational, is risky and arguably unsustainable (1). Crop diversification emerged as an important strategy for achieving sustainable agriculture in Bangladesh (2). On-farm trials were conducted to evaluate new cropping patterns in the Rangpur district and promote crop diversification among smallholder farmers. This brief summarizes the results from post-intervention outcomes in farmer behavior covering a) preferred cropping patterns among farmers; b) perceived benefits, challenges, and transaction costs of crop diversification, and c) market awareness among on-farm trial farmers. Data were collected through face-to-face interviews in the Rangpur district.24 page
Feed the Future Zimbabwe mechanization and extension activity FY 2025 Quarter One Report: October 1, 2024 - December 31, 2024
No full textThis is the Financial Year 2 (FY2) annual report covering October 2023 to September 2024 of the Feed the Future Zimbabwe Mechanization and Extension Activity, funded by USAID/Zimbabwe under the contract AID-BFS-IO-17-00005 and implemented by the International Maize and Wheat Improvement Center (CIMMYT) in cooperation with its subcontractor. The FY2 annual report outlines key achievements by the Mechanization Activity in its quest to improve smallholder farmers' land and labor productivity and income and reduce drudgery through mechanization. Major efforts focused on establishing service providers, increasing awareness and demand for mechanization, promoting irrigation solutions, and facilitating access to finance.48 page
A penalized regression method for genomic prediction reduces mismatch between training and testing sets
No full textGenomic selection (GS) is changing plant breeding by significantly reducing the resources needed for phenotyping. However, its accuracy can be compromised by mismatches between training and testing sets, which impact efficiency when the predictive model does not adequately reflect the genetic and environmental conditions of the target population. To address this challenge, this study introduces a straightforward method using binary-Lasso regression to estimate beta coefficients. In this approach, the response variable assigns 1 to testing set inputs and 0 to training set inputs. Subsequently, Lasso, Ridge, and Elastic Net regression models use the inverse of these beta coefficients (in absolute values) as weights during training (WLasso, WRidge, and WElastic Net). This weighting method gives less importance to features that discriminate more between training and testing sets. The effectiveness of this method is evaluated across six datasets, demonstrating consistent improvements in terms of the normalized root mean square error. Importantly, the model's implementation is facilitated using the glmnet library, which supports straightforward integration for weighting beta coefficients
Development of climate smart mechanization and irrigation lending: status report on supply chain partner engagement 2024
No full text11 page
Identification and management of Bipolaris sorokiniana in wheat and barley in Southeast Kazakhstan
No full textWheat and barley serve as significant nutrient-rich staples that are extensively grown on a global scale, spanning over 219 million hectares. The annual combined global yield is 760.9 million tons, with Kazakhstan contributing 14.3 million tons of wheat and 3.83 million tons of barley to this total. The productivity of grain crops has declined annually due to fungal disease, especially root and crown rot caused by Bipolaris sorokiniana and Fusarium spp. Research has focused on pinpointing the pathogens responsible for common root rot in various types of wheat and barley grown in Southeast Kazakhstan. The main goal was to examine the efficacy of certain chemical and biological substances in safeguarding barley seedlings during the early growth stage against root rot root rot. Moreover, this study sought to gauge their effects on seed quality by examining aspects such as germination rates, the colonization of seeds by particular fungal pathogens, and the overall vitality of seeds and seedlings. Visual inspection of the plants revealed that the prevalence of B. sorokiniana was an average of 51.8%, and that of Fusarium species was 58.6%. Three isolates were obtained from the roots of the winter wheat promising line 231, three from the spring wheat roots of the Kazakh variety 10, four from the winter wheat variety Steklovidnaya variety 24, fourteen from the spring barley variety Symbat, and fourteen from the winter barley variety Aidyn variety 2. The external spread of common root rot on spring wheat and spring barley varieties reached 50% and 53%, respectively. Promising line 231 of winter wheat and variety Kazakh 10 of spring barley were affected by the disease by 60%, whereas the winter wheat Steklovidnaya 24 was impacted by 67%. Molecular analysis of B. sorokiniana isolates via species-specific primers (COSA_F/COSA_R) from infected plant tissues confirmed their identification. Koch postulates were fulfilled for B. sorokiniana isolates Kz 48, 60, and 82 on Steklovidnaya 24 winter wheat and Symbat spring barley varieties. Biological products such as Phytosporin-M and Sporobacterin-Rassada significantly reduced the level of fungal infection, confirming their potential as environmentally safe plant protection agents.O trigo e a cevada são alimentos básicos ricos em nutrientes, cultivados extensivamente em escala global, abrangendo mais de 219 milhões de hectares. A produção global combinada anual é de 760,9 milhões de toneladas, com o Cazaquistão contribuindo com 14,3 milhões de toneladas de trigo e 3,83 milhões de toneladas de cevada para esse total. A produtividade das culturas de grãos diminui anualmente devido a doenças fúngicas, especialmente podridões de raízes e copas causadas por Bipolaris sorokiniana e Fusarium spp. A pesquisa se concentrou em identificar os patógenos responsáveis pela podridão radicular comum em vários tipos de trigo e cevada cultivados no sudeste do Cazaquistão. O objetivo principal era examinar a eficácia de certas substâncias químicas e biológicas na proteção das mudas de cevada durante o estágio inicial de crescimento contra a podridão das raízes. Além disso, o estudo procurou avaliar os seus efeitos na qualidade das sementes, examinando aspectos como as taxas de germinação, a colonização das sementes por determinados fungos patogênicos e a vitalidade geral das sementes e mudas. A inspeção visual das plantas indicou prevalência média de B. sorokiniana de 51,8% e de espécies de Fusarium de 58,6%. Três isolados foram obtidos a partir de raízes da linha promissora de trigo de inverno 231, e três de raízes de trigo de primavera da variedade cazaque 10, quatro de trigo de inverno variedade Steklovidnaya 24, quatorze de cevada de primavera variedade Symbat e quatorze de cevada de inverno variedade Aidyn 2. A disseminação externa da da podridão radicular comum nas variedades de trigo de primavera e cevada de primavera foi de 50% e 53%, respectivamente. A linha promissora 231 de trigo de inverno e a variedade cazaque10 de cevada de primavera foram afetadas pela doença em 60% das unidades, enquanto o trigo de inverno Steklovidnaya 24 foi afetado em 67% das unidades. A análise molecular de isolados de B. sorokiniana, utilizando primers específicos da espécie (COSA_F/COSA_R) de tecidos vegetais infectados, confirmou sua identificação. Os postulados de Koch foram cumpridos para os isolados de B. sorokiniana Kz 48, 60 e 82 em variedades de trigo de inverno Steklovidnaya 24 e cevada de primavera Symbat. Produtos biológicos como Fitosporin-M e Sporobacterin-Rassada reduziram significativamente o nível de infecção fúngica, confirmando seu potencial como agentes de proteção de plantas ambientalmente seguros
Economic, social and environmental ex ante impacts of scaling mechanized direct-seeded rice technology package: evidence from Cambodia
No full textDirect broadcast seeding, the dominant rice establishment method among smallholder farmers in Southeast Asia, is associated with suboptimal rice productivity, profitability and environmental sustainability. Mechanized direct-seeded rice with complementary agronomic management practices, has been proposed to address these challenges and improve outcomes relative to those of broadcast seeded rice. Yet there is sparse evidence to date on the potential impacts of scaling this technology package, particularly from a sustainability lens. This study assesses the potential economic, social and environmental impacts of scaling the mechanized direct-seeded rice technology package in Cambodia. We use data from on-farm validation trials, a baseline farm-household survey, and secondary sources to parameterize a partial equilibrium economic surplus model to estimate the potential impacts. Results show that investments in scaling the technology package can generate high economic returns, reduce the number of poor people, and substantially mitigate carbon dioxide equivalent emissions. These findings hold even under lower- and higher-than expected yield and input cost changes, which allow for variability in expected investment returns. In addition, the results show considerable variation in potential economic returns between the provinces in Cambodia, which indicates that spatial context likely matters in the potential investment returns. Overall, our findings suggest that policy interventions to promote wider adoption of the technology package are vital entry points to harnessing the potential benefits of the mechanized direct-seeded rice technology package.27 page
Genomic insights into the modifications of spike morphology traits during wheat breeding
No full textOver the past century, environmental changes have significantly impacted wheat spike morphology, crucial for adaptation and grain yield. However, the changes in wheat spike modifications during this period remain largely unknown. This study examines 16 spike morphology traits in 830 accessions released from 1900 to 2020. It finds that spike weight, grain number per spike (GN), and thousand kernel weight have significantly increased, while spike length has no significant change. The increase in fertile spikelets is due to fewer degenerated spikelets, resulting in a higher GN. Genome-wide association studies identified 49,994 significant SNPs, grouped into 293 genomic regions. The accumulation of favorable alleles in these genomic regions indicates the genetic basis for modification in spike morphology traits. Genetic network analysis of these genomic regions reveals the genetic basis for phenotypic correlations among spike morphology traits. The haplotypes of the identified genomic regions display obvious geographical differentiation in global accessions and environmental adaptation over the past 120 years. In summary, we reveal the genetic basis of adaptive evolution and the interactions of spike morphology, offering valuable resources for the genetic improvement of spike morphology to enhance environmental adaptation.5470-548