International Crops Research Institute for the Semi-Arid Tropics
ICRISAT Open Access RepositoryNot a member yet
12134 research outputs found
Sort by
Flies Pests of Food Legumes
No full textThe agromyzid flies are important pests of many agricultural crops, including food legumes. The agromyzids belonging to the genera Melanagromyza, Phytomyza, Liriomyza, and Ophiomyia severely damage legume crops worldwide, causing enormous yield losses. Agromyzids are strictly host-specific, and few species exhibit oligophagy. Some species (Phytomyza spp.) are highly polyphagous, feeding on diverse host plants. The adult agromyzids are small flies, and the larval stages are internal feeders that damage leaves, stems, seeds, pods, or roots of the plants. Successful control of these pests requires strict monitoring, detection, identification, and knowledge of their host plants and biology. In this chapter, the economically important agromyzid flies infesting legume crops, their management, and other aspects are described in detail
Influence of Bidirectional Reflectance Distribution Function in Estimating Basic Soil Properties Using Airborne Hyperspectral Data
Get PDFRecent studies on hyperspectral remote sensing (HSR) have shown that the estimation accuracy of different vegetation characteristics improves when the HSR data are corrected for the bidirectional reflectance distribution function (BRDF) effects. Similar studies involving soil parameters are limited. Here, we used the BRDF-corrected HSR data collected using the airborne visible-infrared imaging spectrometer-next generation (AVIRIS-NG) sensor to estimate soil parameters over a 138-km2 agricultural catchment. Surface soil samples were collected from 173 ground reference locations (GRLs) from this catchment to measure clay and sand contents, pH, electrical conductivity (EC), and soil organic carbon (SOC) contents. The BRDF correction was applied using the flexible BRDF (FlexBRDF) algorithm, and a polynomial unmixing approach was used to extract soil spectra from the corrected image. The BRDF correction successfully removed the shading effects and produced smooth transitions along the overlapping regions when multiple AVIRIS-NG images were mosaicked. Upon unmixing, soil spectra could be extracted at 140 GRLs when BRDF-corrected spectra were used, while uncorrected spectra produced soil spectra only for 114 GRLs. Chemometric models were validated using 109 common GRLs to compare estimation accuracy across laboratory-measured soil spectra ( SSLab ) and those obtained from unmixing of BRDF-corrected and uncorrected spectra. The coefficient of determination ( R2 ) values in the validation datasets ranged from 0.40 to 0.83 for both the BRDF-corrected and SSLab data, while the uncorrected spectra showed poor estimation accuracy (R2: 0.25–0.56). The resulting root-mean-squared error (RMSE) was reduced by 10% and 47% for the BRDF-corrected soil spectra compared to their uncorrected data. The BRDF-corrected and unmixed soil spectra were used to map soil properties at ~5-m spatial resolution for the entire catchment. Low SOC contents in the resulting maps adjoining the Ganges river flowing through our study site captured the topsoil loss typically observed from river banks. Thus, the BRDF-corrected HSR data not only improved the accuracy of soil estimates but also showed potential to identify vulnerable areas needing precision management measures with high spatial resolution
Restoring Degraded Landscapes for Sustainable Crop Intensification and Improving the Livelihood Security of the Particularly Vulnerable Tribal Groups in Odisha, India
No full textLand degradation is one of the major challenges that affects about 29% of land area and impacting nearly 3.2 billion people, globally. Land degradation takes many forms and affects soil, forests, biodiversity, water and socio-economic services derived from the ecosystem. Moreover, rapidly changing land use and deforestation in uplands leads to accelerated land degradation and generates large volume of runoff along with high rate of siltation. This runoff loss not only creates water/moisture deficit in uplands but
also invades mid- and lowlands of the landscape due to flooding, eutrophication, and heavy siltation in water bodies. These changes have been accompanied by negative externalities such as climate change, loss of biodiversity, poor retention ability of the landscape and heavy land degradation. These alterations have influenced number of planetary boundary conditions which are negatively influencing available natural resources, sustainability, and productivity of the landscape at local, regional, and global scale. These challenges are catastrophic, especially in uplands, those were historically covered with forests however, converted into desolated landscapes over the period. The impact is severe as these landscapes largely belonging to marginal and small landholders which coincide with high poverty and malnutrition. With the absence of resource availability, in habitants residing in these areas are compelled to migrate to urban centres in search of their livelihoods leaving behind their valuables and families. This situation often result in a precarious socio-economic conditions including large scale unemployment and delinquency in the society. However, this also provides an opportunity to harvest surface runoff through sciencebased
landscape resource conservation approaches using both engineering and biological measures. This facilitates improving the water retention ability of the landscapes which governs the water availability in surface and groundwater systems that facilitates sustainable intensification and diversification of agri-food system
Targeting nutrient sources and forms to identify yield-limiting nutrients for wheat under contrasting rainfall regimes and landscape positions in mixed-farming systems
Get PDFWheat yield gap in Ethiopia is high due to low nutrient availability, soil heterogeneity, undulating landscape, and climate. A study was conducted to identify yield-limiting nutrients for wheat yield under varying landscape positions and rainfall regimes. The treatments included all nutrients in blended (All-Blend), compound (All-Comp), and individual (All-Ind) forms containing N, P, K, S, Zn, and B, while K, S, Zn, and B omitted treatments were (All-Blend)-K, (All-Blend)-S, (All-Blend)-Zn, and (All-Blend)-B. Besides, NP only, 50 and 150% of the rate of all nutrients in the blended form (All-Blend), and a control without any nutrients were included. Results showed that the highest yield was obtained from the application of 150% of All-Blend across landscape positions and rainfall regimes, with grain yield improvement of 109.5% (2.54 t ha−1) by applying 150% of All-Blend under the foot slope position and high rainfall regime compared to the control and yield improvement of 72.5% under the low rainfall regime. With the control treatment grain yield was lower by 27–70% across landscape positions and rainfall regimes. The grain yield penalties due to K, S, Zn, and B omission were 0.54–9% over landscape positions and rainfall regimes compared to applying All-Blend, implying that the omission of K, S, Zn, and B were not yield-limiting nutrients for wheat production in the study areas. Thus, it will be crucial to consider landscape strata and rainfall regimes to optimize NP rates. Further study is also suggested as nutrient applications in blended, compound, or individual forms are inadequate to conclude
Tree integration in conservation agriculture: A case study of teak (Tectona grandis) + bael (Aegle marmelos) based agroforestry in the Bundelkhand region
Get PDFThe present study was carried out during the winter (rabi) seasons of 2021–22 and 2022–23 at ICAR-Central Agroforestry Research Institute, Jhansi, Uttar Pradesh to study the impact of conservation agriculture practices within a teak (Tectona grandis L.)+ bael (Aegle marmelos L.)-based agroforestry system on growth rate and yield parameters of tree and crop component, as well as on soil properties. It examined the effect of tillage methods and residue retention on the growth and yield of chickpea (Cicer arietinum L.) and linseed (Linum usitatissimum L.) as well as soil properties. The experiment was laid out in a randomized block design (RBD), with three replications having eight treatments of comprising combinations, viz. Tillage methods (conventional and minimum); Cropping systems (sorghum-chickpea and maize-linseed); and Residue management practices (residue retention and no retention). Results indicated that residue retention under conventional tillage significantly enhanced plant height and dry matter accumulation in both linseed and chickpea. Crop yields were comparable under conventional and minimum tillage, although residue retention significantly boosted the yields of both crops. Conservation agricultural practices contributed to higher productivity in the teak+ bael-based agroforestry system. Residue retention improved soil organic carbon content by 24–39% compared to no residue retention. Additionally, nutrient availability (N, P, K, S, Zn, Fe, Mn, and Cu) was enhanced through minimum tillage combined with residue retention
Application of Genome Editing Tools for Genetic Enhancement of Pulses for Stress-Resilient Traits
No full textGenome editing tools can revolutionize the genetic enhancement of pulses for stress-resilient traits. Genome editing tools, such as CRISPR/Cas9, TALENs, and ZFNs, enable precise modification of an organism’s DNA, offering a broad range of applications from understanding molecular responses to various environmental cues to improving resilience in pulse crops. These tools help to introduce nucleotide variations leading to the generation of new, modify existing, or delete alleles of our genes of interest, leading to phenotypic changes. In pulse crops, genome editing can help to develop genotypes tolerant to abiotic stresses, including moisture, temperature, and poor soil, and resistant to biotic stresses, including diseases and insect pests. The application of genome editing tools in pulses is still in its early stages but has the potential to significantly contribute to improving global food security and sustainability
Harnessing Genebank Diversity for Future-ready Crops
No full textPlant genetic resources for food and agriculture (PGRFA) play a vital role in ensuring sustainable agriculture and food security worldwide. The conservation of PGRFA is primarily through ex-situ genebanks, with approximately 7.4 million germplasm accessions stored in 1,750 genebanks globally. Notably, the 11 CGIAR genebanks conserve over 730,000 accessions of crop, forage and tree species, and are made available through the Plant Treaty's multilateral system. These resources are conserved at CGIAR genebanks and safety duplicated Svalbard Global Seed Vault and at one more genebank under long term storage condition. Exsitu genebanks, that conserve PGRFA serve as vital repositories for preserving crop diversity. The ICRISAT genebank is one of the largest repositories in the CGIAR system and conserves over 131,000 accessions of 11 crops and their wild relatives. Among the 11 crops, groundnut is one of the important crops with 15393 accessions from 93 countries including 7484 landraces and 401 accessions of wild species. National genebank of India conserves 13893 accessions of
groundnut both under long term and medium-term storage conditions. These genetic resources are reservoirs of useful genes that can contribute to the present and future crop improvement programs. To promote the utilization of these resources, ICRISAT genebank developed diverse subsets in groundnut, such as core (1704 accessions), and mini core (184 accessions). Extensive evaluation of these subsets resulted in the development of trait-specific subsets for rust and late leaf spot (76 accessions) and multiple trait-specific subset (56 accessions). Furthermore, SSRbased
genotyping of the global groundnut composite collection led to the formation of reference set (300 accessions). ICRISAT genebank, so far has distributed over 1.72 million seed samples to users in 151 countries, including, 102,859 samples of groundnut. Germplasm and breeding material distributed from ICRISAT led to development and release of 250 varieties in 39 countries. Genome-wide association studies on the mini-core collection have led to the identification of several MTAs linked with key traits such as fresh seed dormancy, stem rot resistance and nutritional traits. These genomic resources provide ample opportunities for germplasm curators, breeders and molecular biologists to optimize genebank operations, allele mining, identify genetically diverse material with traits of importance and accelerate crop improvement to enhance production in the face of climate change
Effect of fermentation on the proximate composition, antinutrients, bioaccessibility of minerals, and sensory quality of pearl millet-based Injera
Get PDFPearl millet is a cereal rich in both macro- and micronutrients; however, it also contains high levels of antinutrients, such as phytate, tannin, and phenols, which can hinder nutrient absorption. This study examined the impact of fermentation on the nutrient composition, antinutritional content, mineral bioaccessibility, and sensory quality of Injera prepared from pearl millet flour alone, as well as from a composite flour of pearl millet and maize (in 1:1 and 1:2 ratios). Fermentation significantly improved the nutrient profile and sensory attributes of Injera samples. Significant improvements (p < .05) were observed in all Injera samples, with reductions in phytate (81.5%–99.2%) and tannin (72.4%–96.1%) contents, and increased mineral bioaccessibility for iron (62.1%–73.5%), zinc (53.8%–83.3%), and calcium (19.6%–54.6%). These findings showed that traditional fermentation methods can effectively decrease antinutrients, enhance the nutrient profile, and improve mineral bioaccessibility in pearl millet-based Injeras
South Asia's Ecosystems Are a Net Carbon Sink, But the Region Is a Major Net GHG Source to the Atmosphere
Get PDFAs part of the REgional Carbon Cycle Assessment and Processes-2 (RECCAP-2) project of the Global Carbon Project, here we estimate the GHG budgets (anthropogenic and natural sources and sinks) for the South Asia (SA) region as a whole and each country (Afghanistan, Bangladesh, Bhutan, India, Nepal, Pakistan, and Sri Lanka) for the decade of 2010–2019 (2010s). Countries in the region are experiencing a rapid rise in fossil fuel consumption and demand for agricultural land, leading to increased deforestation and higher greenhouse gas emissions. This study synthesizes top-down (TD) and bottom-up (BU) dynamic global vegetation model results, BU GHG inventories, ground-based observation upscaling, and direct emissions for major GHGs. The fluxes for carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) analyzed include fossil fuel emissions, net biome productivity, land use change, inland waters, wetlands, and upland and submerged soils. Our analysis shows that the overall total GHG emissions contributed to a net increase of 34%–43% during the 2010s compared to the 2000s, primarily driven by industrial activities. However, terrestrial ecosystems acted as a notable exception by serving as a CO2 sink in the 2010s, effectively sequestering atmospheric carbon. The sink was significantly smaller than overall carbon emissions. Overall, the 2010s GHG emissions based on BU and TD were 4,517 ± 639.8 and 4,532 ± 807.5 Tg CO2 eq, with CO2, CH4, and N2O emissions of 2165.2 ± 297.1, 1,404 ± 95.9, and 712 ± 466 Tg CO2 eq based on BU models 2,125 ± 515.1, 1,531 ± 205.2, and 876 ± 446.0 Tg CO2 eq based on TD models. Total emissions from SA in the 2010s accounted for approximately 8% of the global share. The terrestrial CO2 sinks estimated by the BU and TD models were 462.9 ± 195.5 and 210.0 ± 630.4 Tg CO2, respectively. Among the SA countries, India was the largest emitter contributing to 80% of the region's total GHG emissions, followed by Pakistan (10%) and Bangladesh (7%)
A Comprehensive Review of Aflatoxin in Groundnut and Maize Products in Africa: Prevalence, Detection and Mitigation Strategies
Get PDFAflatoxins are a toxic secondary metabolite, mainly produced by the fungi Aspergillus flavus and A. parasiticus. Aflatoxin contamination of food is a global concern, as they are carcinogenic, mutagenic and teratogenic. Groundnuts and maize products are highly susceptible to aflatoxin contamination at both pre- and postharvest stages; this leads to a great risk for those countries that rely on these products for food and nutrition security as well as income. Groundnut and maize products have contributed a substantial amount of aflatoxin exposure to human and animal health risks, especially in countries that experience tropical climate and recurrent drought, favouring mould developments. Due to the strange health impacts of aflatoxin in agricultural commodities, different countries have set the acceptable limits for groundnut and maize products, whereas most of the countries use the same limit for both commodities. Detection and quantification of aflatoxins in groundnut and maize products are mainly through enzyme-linked immunoaffinity assay (ELISA) and high-performance liquid chromatography (HPLC), among others. However, currently rapid, accurate and cost-effective techniques are emerging to quickly monitor and enforce the regulation limits. Among the widely applied strategies for aflatoxin mitigation are biological control including atoxigenic Aspergillus strains, plant extracts, and chemical and physical methods of detoxification and decontamination. Aflatoxin decontamination using plant extracts is promising for most countries in sub-Saharan Africa owing to the availability, ease of access and affordability; however, there is a need for further screening to isolate the bioactive ingredients. This review could provide insight into the researchers, stakeholders and consumers on the prevalence of aflatoxin in groundnut and maize products as well as mitigation strategies to improve food safety