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- ItemA Conceptual Framework for Delivering Improved Fertilizers to Smallholder Farmers in Africa(2018) Wendt John; L.W. MbuthiaMost smallholder African farmers have access to only NP and NPK fertilizers. A host of secondary and micronutrient deficiencies have been identified throughout the continent, which when addressed, results in marked yield improvement. A challenge is to get balanced fertilizers (those that supplement available fertilizers with secondary and micronutrients) to these smallholders, who often can neither afford nor access quality soil analyses. We lay out a conceptual framework, which is being implemented to varying degrees in various African countries, to deliver improved fertilizers to smallholders. The SMART framework stands for Soil testing. Mapping. Recommendations development, and Technology transfer. Soil testing is done on a broad scale to identify major likely deficiencies, using complete analyses by a qualified laboratory. The major deficiencies are mapped, and crop-specific recommendations are developed through on-farm "best bet" and omission trials, considering predominant deficiencies and crop-specific nutrient demands. Once superior fertilizers have been validated, these recommendations are transferred to farmers by commercial fertilizer interests. Fertilizer regulations in many African countries need to be adjusted to accommodate new fertilizers, as regulations were often designed primarily for commodity NPK fertilizers.
- ItemA secured Market as a Trigger for Organizing the Value Chain: The Case of Yellow Maize and Sesame Partnerships in Mali(2017) Faoussa Tadjo ; Youssouf Traore; Baba TogolaThis paper discusses the development of sustainable sourcing relationships between lead firms targeting secure markets and producers through a collector system for yellow maize and sesame. Coordinating value chains for these commodities presents unique challenges, including the need to establish sourcing relations with producers and the difficulty of maintaining lasting relationships with sesame producers due to the demand-driven market. The lead firms, SONAF for maize and PROSEMA for sesame partnered with 2SCALE to develop strategies for engaging with stakeholders, particularly producer organizations, and utilized collectors to ensure a secure sourcing of products. The partnership focused on strengthening the organization of producer cooperatives and their relations with other agribusiness cluster members, resulting in enhanced coordination among actors in Mali's agricultural sector. This case study specifically examines SONAF's sourcing of yellow maize in Mali, highlighting the initial situation, the SONAF-2SCALE partnership, interventions implemented, and the results achieved, including increased formalization of business relationships, improved access to quality seeds, establishment of input credit mechanisms, and capacity strengthening of producers. Overall, the study demonstrates the effectiveness of value chain coordination and stakeholder engagement in promoting sustainable sourcing practices and fostering agricultural development in challenging market environments.
- ItemAfrica Fertilizer Summit Proceedings(2007-04) IFDCThe New Partnership for Africa's Development (NEPAD) recognizes the crucial role of economic growth in Africa and the need for a comprehensive strategy to promote agricultural development, food security, and rural progress. To achieve this vision, NEPAD has adopted the Comprehensive Africa Agricultural Development Programme (CAADP), which aims to achieve 6% annual growth in agricultural production. However, African farmers face numerous challenges, including low productivity, limited access to agricultural technologies, and weak markets. A significant obstacle is the severe depletion of soils due to decades of nutrient mining, resulting in impoverished soil fertility and the inability to feed the growing population sustainably. Addressing Africa's fertilizer crisis is essential for unleashing the continent's agricultural potential. Currently, fertilizer usage in Africa is only 10% of the global average, averaging eight kilograms per hectare. To overcome this crisis, urgent and bold actions are required. The African Union (AU) convened the Africa Fertilizer Summit in 2006, where African leaders expressed their commitment to solving the fertilizer crisis and achieving a Green Revolution in Africa. The AU's resolution outlines several vital measures to accelerate farmers' access to fertilizers. These include increasing fertilizer usage from the current average of 8 kilograms per hectare to at least 50 kilograms per hectare by 2015, reducing the cost of fertilizer procurement through policy harmonization and tax exemptions, improving farmers' access to fertilizers through networks and subsidies, and investing in infrastructure and financing facilities for input suppliers. The resolution also emphasizes promoting regional fertilizer production, trade, and intra-regional cooperation. Africa's agricultural productivity has stagnated, resulting in chronic food insecurity, poverty, and economic stagnation. By learning from the successful Green Revolution experiences in Asia and Latin America, Africa can unlock its agricultural potential and achieve sustainable development. Increasing productivity, improving farmers' access to inputs, and addressing the fertilizer crisis are essential steps toward ending hunger, reducing poverty, and spurring economic growth in Africa. Establishing monitoring mechanisms and a dedicated financing mechanism will ensure the effective implementation of these measures. With strong commitment and collaboration among governments, development partners, and the private sector, Africa can pave the way for a uniquely African Green Revolution that ensures its people's dignity, peace, and food self-sufficiency.
- ItemCalibration of Solvita CO2 Burst System for Reducing Nitrogen Pollution in Agronomic Systems(2021-11-10) Annabelle E. McEachin; Elizabeth A. Guertal; Audrey V. Gamble; Upendra SinghOver application of nitrogen (N) fertilizer causes reduced fertilizer use efficiency, and possible drinking water contamination and eutrophication of affected waterways. Nitrogen fertilizer is often over applied because standard soil tests do not include a well-calibrated soil-test for N. This is partly because it is challenging to account for the N soil microorganisms will mineralize during the growing season. Quantification of potentially mineralizable soil nitrogen by multiweek incubations is time consuming and often not possible for large scale commercial labs. CO2 base trap titrations and analysis with gas chromatography are also tedious and not suitable for high volume use. The Solvita Field CO2 Test provides an alternative that only requires a 24-hour incubation period, with evolved CO2 directly correlated to the quantity of N mineralized. The objective of this project was to conduct incubation experiments on soils gathered from Alabama fields under a variety of management strategies (including high crop residue) and to compare N mineralization from that predicted via the initial Solvita test. Samples were collected from four crop rotation systems for initial testing, with soils sampled from the 0-15cm layer for: 1) conventional tillage corn with complete N-P-K fertilization, 2) no tillage turfgrass with minimal fertilization, 3) conservation tillage cotton with and complete N-P-K fertilization, and 3) conservation tillage cotton with rye cover and complete N-P-K fertilization. Initial analysis have not indicated a strong correlation between the three traditional measurement methods and the Solvita test data.
- ItemCan Controlled-Release Phosphate Fertilizer Improve Phosphorus Efficiency?(2012-10-23) Sampson Agyin-Birikorang; Upendra Singh; Joaquin Sanabria; Wendie D. BibleMany phosphorus (P) uptake kinetic studies show that the pattern of P uptake in the early growth stages of annual crops is generally similar to crop dry matter accumulation. Thus, we hypothesized that matching P delivery to crops’ P demand could increase P uptake and use efficiency of annual crops in the season of P application. In greenhouse studies, we simulated controlled-release P fertilizer by making small, periodic additions of fertilizer P directly into the root zone of two cereal crops through “feeding” tubes for quick and continual plant P uptake. The crops were grown on a P deficient highly weathered soil with P retention capacity of ~20%. Split application of P, where a portion of P is applied at planting and other portions applied at subsequent time intervals, was utilized as a simulation of controlled-release P fertilizer. Upland rice and winter wheat were used as test crops in the spring-summer and winter seasons, respectively. The crops’ growth phenology was monitored, and samples were harvested at heading and maturity stages to determine yield and P uptake. Preliminary data show that supplying P in small doses over time shortened the days to panicle initiation, heading and maturity, and improved P uptake efficiency relative to basally applying P at planting. Treatment effects on yield, so far, are not conclusive. However, based on P uptake efficiency and growth rate of the two cereal crops, we hypothesize that controlled-release P fertilizer could improve P efficiency in the season of P application. This could have major agronomic and environmental benefits.
- ItemCan Optimal Fertilizer Application Rate Differ from Economically Optimal Fertilizer Rate? A Case Study with Zinc Application for Maize Production in Northern Ghana(2021-11-09) Sampson Agyin-Birikorang; Ignatius Tindjina; Haruna W. Dauda ; Job FugiceAlthough fertilizer recommendations are based on optimal yields, the minimal fertilizer application rate that ensures both high productivity and profitability will be attractive to most farmers. In a three-year study at six locations across the savanna agroecological zones (AEZs) of northern Ghana, we quantified maize yield responses to seven Zn application rates (0 to 15 kg Zn ha-1), and determined the economically optimal Zn rate for maize production. Across all experimental sites and for the three growing seasons, maize grain yield followed the order: 15 kg Zn ha-1 = 12.5 kg Zn ha-1 = 10 kg Zn ha-1 = 7.5 kg Zn ha-1 > 5 kg Zn ha-1 > 2.5 kg Zn ha-1 > control, suggesting that 7.5 kg Zn ha-1 was the optimal Zn application rate. However, based on agro-input prices at local level and farmgate prices of maize, the potential gross profits resulting from Zn application was maximized at 5 kg Zn ha-1 instead. At Zn application rates of 12.5 and 15 kg ha-1, there was a significant increase in grain Zn concentration. From the combined results, we conclude that for increased profitability from the maize production system, Zn application rate of 5 kg ha-1 is economically justified, but for increasing the Zn content of the grains, Zn application rate should not be lower than 12.5 kg ha-1. Nonetheless, unless premium prices are paid for Zn-enriched maize grains, for sustainable and profitable maize production in these Zn-deficient soils of the savanna AEZs of northern Ghana, ideal Zn applications rate should be 5 kg Zn ha-1, although the optimum Zn application rate was observed to be 7.5 kg ha-1.
- ItemCan Secondary and Micronutrients Really Increase Maize Productivity? A Case Study in the Savanna Agroecological Zones of Northern Ghana(2023-11-01) Sampson Agyin-Birikorang; Raphael Adu-Gyamfi; Job Fugice; Ignatius TindjinaOver the past decades, fertilizer recommendation for maize production in savanna agroecological zones of northern Ghana has been NPK-based. However in recent times there is a strong push for the inclusion of secondary- and micro-nutrients in the fertilizer recommendations. During the 2018 and 2019 growing seasons, we conducted nutrient omission trials in 12 locations within the Sudan savanna and Guinea savanna agroecological zones of northern Ghana to quantify maize yield gaps resulting from omission of secondary and micronutrients from NPK-only fertilization for maize production. In the 2018 and 2019 growing seasons, applying only NPK fertilizer resulted in average yields of 3.22 and 3.89 t ha−1, respectively, in the Guinea savanna agroecological zone and 2.0 and 2.65 t ha−1, respectively, in the Sudan savanna agroecological zone. During the two growing seasons, application of sulfur (S), zinc (Zn), and boron (B) in addition to the NPK fertilizers (“balanced” fertilization) resulted in an average of 60% and 64% yield increases over those of the NPK-only treatment in the Sudan savanna and Guinea savanna agroecological zones, respectively. Compared to balanced fertilization, omission of S, Zn, and B reduced grain yield by an average of ~34%, ~28%, and ~14%, respectively, in the Guinea savanna agroecological zone and 27%, 29% and 15%, respectively, in the Sudan savanna agroecological zone. The combined data suggest that, even though secondary and micronutrients are needed in small quantities by plants relative to N, P, and K, they have an enormous effect on crop productivity. Therefore, to ensure sustainably increased maize productivity in the savanna agroecological zones of northern Ghana, fertilizer recommendations should not be restricted to only NPK fertilizers; limiting secondary and micronutrients must be accounted for in a holistic and balanced fertilizer recommendation.
- ItemCapping Fertilizer Use while Enhancing Food and Nutrition Security in China(2016-03) Bindraban, Prem S.; Marco Ferroni; Dominik Klauser; Christian O. Dimkpa; Wendt John; Yam Kanta Gaihre; Kalimuthu Senthilkumar; Deborah Bossie; Weifeng Zhang; Kempen Bas ; Satish Chander; Renu Pandey; Jason C. White; Bonnie Mcr Jaffcrty!; Scott AngleDespite concerns about the ability of China to be self-sufficient in food, it has increased the per capita availability of food for its 1.4 billion people and dramatically reduced food insecurity over the past decades. However, China's self-sufficiency in food production came with dramatic environmental trade-offs due to excessive use of fertilizers. In response, the government of China imposed a policy of zero growth in the use of chemical fertilizers by 2020, with a challenge to the agricultural and fertilizer community to improve the nutrient use efficiency (NUE) of crops. These objectives have to be met while still ensuring food and nutrition security, and sustaining ecosystem health. In this paper we make a case for revisiting the functioning of fertilizers, in order to achieve a more effective and multifaceted impact on ecology and society. This leads to the notion of adopting a range of strategies with the potential for addressing the low NUE. These include identification of currently most effective fertilizer products and improved nutrient management practices for the immediate term, while designing innovative fertilizers based on plant nutrient physiology, developing "smart" fertilizers that recognize plant cues, deploying bio-nano-technology, and fortifying basic fertilizers with micronutrients.
- ItemClimate-Smart Fertilizers: Pioneering Tools to Address an Overlooked Yet Disruptive Problem(2023-11-01) Tiziano Celli; Katherine Smith; Job Fugice; Jay Schwalbe; Joshua McEnaney; Nicolas PinkowskiNitrogen (N) fertilizers are essential for enhancing crop productivity. However, both production and soil application responses related to N fertilizers can lead to significant greenhouse gas (GHG) emissions. Conventional production methods use fossil fuels and emit 4 lbs of CO2 per lb of N. Once applied, reactions in the soil can produce nitrous oxide (N2O) that constitutes up to 6% of US GHG emissions. N2O emissions are lower in absolute mass than CO2, but their warming effect is 300 times greater over a century. Agriculture is responsible for 75% of global N2O emissions, primarily due to N fertilizer use. Nitricity Inc. is committed to providing innovative solutions for reducing these environmental concerns. In 2022, Nitricity partnered with the International Fertilizer Development Center (IFDC) to implement a containerized production system and produce N fertilizer using air, water, and renewable energy (hydroelectric power) on-site in Muscle Shoals, AL. The fertilizer was used for experiments with two objectives: quantifying N2O emissions from different fertilizer sources and assessing the effectiveness of continuous monitoring using the Picarro G2508 Gas Concentration Analyzer. Two soil types were fertilized with the equivalent of 200 kg N/ha from either Urea or Calcium Nitrate (CN) produced with Nitricity's technology and two different calcium sources. The results demonstrated that CN significantly reduced soil N2O emissions compared to urea, regardless of the calcium source. The study also highlighted the efficacy of the Picarro G2508 Analyzer in reducing labor costs and continuously monitoring N2O emissions. These findings emphasize the success of Nitricity’s novel, electrified production and the need to explore alternative management practices to mitigate the environmental impact of N fertilizers. By embracing innovation and utilizing available tools, the industry can make substantial contributions to reducing GHG emissions and creating a more sustainable future.
- ItemClimate-Smart Water and Nitrogen Management Strategies for Lowland Rice(2015-03-17) Yam Kanta Gaihre; Bindraban, Prem S.; Upendra Singh; Joaquin Sanabria; M. Abdus SatterWorld Nitrogen (N) fertilizer consumption is around 100 million metric tons and is expected to increase with growing food production. However, the N use efficiency with current surface application of urea is extremely low (35-40%) due to its losses from ammonia volatilization, nitrification, denitrification and runoff, particularly under flooded rice cultivation. N losses disrupt natural ecosystems, impair water quality and contribute to global warming (nitrous oxide [N2O] emissions). Climate-smart technologies maximize synergies while minimizing tradeoffs associated with increased productivity and sustainable farmer income, reduced environmental pollution and reduced vulnerability to climate variability and risks. Technologies that reduce environmental footprint without sacrificing productivity, farmer income and sustainability are more likely be adopted by farmers. Modified urea-N fertilizers and/or subsurface application have resulted in significant reduction in N losses and increased productivity. In Bangladesh subsurface application of urea – urea deep placement (UDP) – has increased rice yield by 15-18% while reducing N use by one-third compared with broadcast urea. UDP also resulted in significant reduction in N volatilization loss (<5% vs. 25-35% with conventional application) and N2O emissions. N2O emissions from UDP fields were as low as emissions from unfertilized N plots, ranging from 20-50 g N2O-N ha-1 (wet season) to 100-160 g N2O-N ha-1 (dry season). Moreover, the drudgery of deep-placement was reduced with the use of affordable applicators, and, combined with a single N application and reduced weeding, it decreased labor requirement by 15-25% compared to broadcast urea. UDP technology has proven to be an effective climate-smart agricultural practice that increases the food production and wellbeing of poor rice farmers and reduces GHG emissions through the combination of reduced N fertilizer use and reduced N losses. Preliminary results also show reduced N2O emissions from UDP under alternate-wetting and drying conditions (AWD). The combination of UDP and AWD resulted in reduced N2O and methane emissions, water saving and higher grain yield compared to continuously flooded conditions with conventional application of urea.
- ItemComparison of Yield Response and Nutrient Use Efficiency between Urea Deep Placement Technology and Farmers' Practice of Surface Broadcasting Urea on Transplanted Lowland Rice in Myanmar(2018) Myint Aung; Z.Y. Myint; S. Thura; Grahame Hunter ; Upendra Singh; Joaquin SanabriaUrea deep placement (UDP) adaptation trials in randomized complete block design with four treatments and three replications were conducted in two wet seasons (2014 and 2015) and two dry seasons (2105 and 2016) at selected sites in the Delta Region of Myanmar to study yield comparison and nutrient use efficiency between UDP and surface broadcasting urea on transplanted lowland rice. The four treatments were: (1) control (0 N), (2) farmers' practice of urea application with farmers' rate (FP). (3) urea broadcasting (UB) with the same rate as UDP, and (4) UDP. A Generalized Linear Mixed Model was used to analyze variances among treatments, locations, and interaction of location by treatment for each year/season. Yield superiority of UDP over other treatments and nutrient use efficiency (NUE) for each urea applied treatment were calculated. Significant differences at Poon) were observed among treatments and locations in every year/season. Significant differences of interaction of treatments by locations at Pons) were found in wet season trials only. UDP gave the highest yield at all times. It was significantly higher than FP treatment and often higher than UB treatment. Yield superiority of UDP over UB and FP was 16-18% in the wet season and 24-28% in the dry season. Nutrient use efficiency with UDP was double the NUE with other N-applied treatments. UDP produced 30 kg of rice grain for every kg of N applied while other treatments produced 14-17 kg of rice grain per kg of N applied. UDP is therefore the more effective technology to apply N fertilizer on transplanted lowland rice, and dry season results indicated that yield with UDP could be expected more with best management practices under favorable water conditions and proper water management.
- ItemDetermination of Optimum Farmyard Manure and Np Fertilizers for Maize on Farmers’ Fields(2001-02) Wakene Negassa; Kefyalew Negisho; Dennis K. Friesen; Joel Ransom; Abebe YadessaA study was initiated in 1997 to introduce the culture of supplementing low rates of NP fertilizers with farmyard manure (FYM) in the maize based farming systems of western Oromia. The treatments were 0/0, 20/20, 40/25 and 60/30 kg N/P ha-1 and 0, 4, 8, and 12 t FYM ha-1 in factorial arrangement in a randomized complete block design with three replications. The experiment was conducted at Laga Kalla, Walda, Shoboka, Harato, and Bako Research Center using BH660 hybrid maize. The FYM used for the experiment was well decomposed under shade and spot applied together with the P fertilizer at planting; N was applied in split form. The residual effects of FYM were investigated for Laga Kalla, Walda and Shoboka during the 1998 cropping season. Statistical analysis revealed that the N/P fertilizers and FYM significantly (p<0.05) increased grain yield in all locations except for Walda in 1997. Interactions of FYM and NP fertilizer rates were significant (p≤0.05) at all locations except for Shoboka. The application of FYM alone at rates of 4, 8, and 12 t ha-1 produced average grain yields of 5.76, 5.61 and 5.93 t ha-1, respectively, compared to 3.53 t ha-1 for the control treatment. Laboratory analysis confirmed that considerable amounts of macronutrients and small amounts of micronutrients were supplied by the FYM. There were significant residual effects of FYM and NP fertilizers applied in 1997 on maize grain yields in 1998. Based on the results of this study, the integrated use of properly managed FYM and low rates NP fertilizers could be used for maize production in the areas under consideration. Moreover, sole applications of FYM on relatively fertile soils like Walda and Harato are useful in maintaining soil fertilty and are encouraging for resource poor farmers.
- ItemDevelopment of Slow Release Carrier of Phosphorus to Improve its Use Efficiency(2016-04) Mandira Barman; Renu Pandey; Anjali; Bindraban, Prem S.The concentration of inorganic phosphorus (P) in soil solution is usually much lower than that of the root cells due to its fixation by different soil components. Developing a controlled release technology to reduce P fixation and loss through run-off will therefore be helpful in enhancing P use efficiency in crops. Low molecular organic acids such as oxalic acid or citric acid are known to solubilise fixed P in soil. Hence, these can be used to increase P availability in soil. Therefore, our aim was to develop controlled delivery system using clay and polymer which can be used as a release carrier of different materials like oxalic acid, P and phosphate solubilising bacteria (PSB) in soil to increase P availability. Clay polymer composite (CPC) was synthesized using poly acrylate and bentonite. After synthesis, the polymers were dried in oven at 100" C. Then dried CPCs were loaded with loaded with oxalic acid, P and PSB. To assess the response of crop to applied CPC a greenhouse experiment was conducted using wheat as a test crop. Treatment combination consisted of oxalic acid @ 40 ppm, half of recommended dose of P through CPC, PSB through CPC and full recommended dose of P (RDP) through di- ammonium phosphate (DAP) fertilizer. Results indicate that at 45 DAS available P in soil was highest in full RDP through DAP treated pots which was at par with half recommended P through CPC and PSB through CPC treated pots, But at harvest available P was much lower in DAP fertilizer treated pots (5.0 mg/kg) than half recommended P through CPC (7.87 mg/kg), PSB through CPC (8.1 mg/kg) and oxalic acid through CPC (6.8 mg/kg) treated pots. Half recommended P and PSB through CPC and DAP fertilizer were equally effective as far as dry matter yield and uptake were concerned. This indicates that half recommended P applied through CPC is able to maintain soil available P for longer period. Also oxalic acid and PSB applied through CPC can be used to solubilize native soil P. Therefore, CPC can be used as controlled delivery system of nutrients and other agrochemicals to improve nutrient use efficiency.
- ItemDifferential Response of Rice Plants to Foliar Application of Iron and Phosphate is Regulated by Antioxidant Scavenging System(2016-03) Sandeep Sharma; Priyanka Borah; Lakshmi Raj; Mukesh Kumar Meena; Bindraban, Prem S.; Mandira Barman; Renu PandeyThis conference paper investigates the differential response of rice plants to foliar applications of iron (Fe) and phosphate (P) and explores the role of the antioxidant scavenging system in regulating this response. Phosphorus and iron are essential nutrients for plant growth and development, and foliar application is a practical approach to supplement these nutrients due to their limited bioavailability in soil. The study conducted experiments to assess how different Fe and P compounds affect rice plants and found varying responses based on the compounds used. Specifically, the paper discusses the impact on antioxidant enzyme activities, lipid peroxidation, nutrient partitioning, and yield-related traits. The results highlight the importance of optimizing nutrient concentrations to achieve better plant growth while avoiding oxidative stress. The findings provide valuable insights into enhancing nutrient management strategies for rice cultivation.
- ItemDrought and Low Nitrogen Tolerant Hybrids for the Moist Mid Altitude Ecology of Eastern Africa(2004-01) Alpha O. Diallo; J. Kikafunda; Legesse Wolde; Omari Odongo; Z. O. Mduruma; W. S. Chivatsi; Stephen N Mugo; Marianne Bänziger; Dennis K. FriesenMaize is the principal food staple of the rural and urban poor of eastern and central Africa, constituting > 50% of the caloric intake derived from cereals in the region. Drought and low soil fertility are among the most important constraints to maize production even in the high potential moist mid-altitude eco-zone. This zone, generally falling within the altitudinal range of 1000-1800 masl and characterized by rainfall of >500 mm and mean temperature of 21.5°C, comprises a total area of approximately 500,000 hectares in Kenya alone, and is among the most densely populated regions on the continent. Though of high potential productivity, fertilizer use is constrained by high costs and lack of credit for small holders. Maize productivity in maize-based cropping systems could be greatly improved using varieties that utilize nitrogen (N) from fertilizers and other sources more efficiently as well as tolerating the periodic moisture stress. Farmers in this region have shown a preference for hybrid maize varieties. The objective of the research described here was to develop hybrid maize varieties adapted this ecology that are tolerant of low soil fertility and drought. Drought and low N tolerant inbred lines developed by CIMMYT-Harare in collaboration with CIMMYT Mexico were crossed with two streak resistant testers (CML202 and CML206) during the 1997-98minor season. In 1999, the resulting crosses were evaluated across 7 sites and compared with local checks under both stressed (managed drought and low N) and unstressed conditions. The selected best single cross hybrids were crossed with 2 other testers (CML78 and CML384) in 2000 and the resulting 3 way-hybrids were evaluated as in 1999. Grain yield and secondary traits such as Anthesis-Silking Interval (ASI), leaf senescence, and number of ears per plant were used to select the most promising materials. Eight drought and low N tolerant 3-way hybrids were identified which yield 24, 15 and 64% more than the best commercial hybrid checks under optimum, low N and drought stress conditions, respectively. These hybrids have the potential to increase yields, reduce input requirements and improve yield stability for resource-poor farmers in densely populated high potential eco-zones of Eastern and Southern Africa.
- ItemDSSAT CERES-Teff Model Development(2021-11-9) Mulugeta Demiss Belew; Willingthon Pavan; Upendra SinghCrop models are powerful tools that describe crop development and growth as a function of crop management, weather, and soil conditions. However, a comprehensive model that captures these factors and their interaction for Teff [Eragrostis tef (Zucc.) Trotter], was initiated only recently. Teff is the most important cereal in Ethiopia grown in about 3.1million hectares (24.17% of the total grain crops). Teff’s popularity is increasing globally due to gluten-free grains with high in calcium and iron content. This presents a growing economic opportunity for Ethiopia and its farmers. Teff is also becoming a viable source of high quality and high yielding hay and silage in a relatively short growing season in the USA. Teff straw is valued as a high quality, low input, warm season fodder. CERES-Rice model within the Cropping System Model platform of the Decision Support System for Agrotechnology Transfer (DSSAT) was used as the module to develop the teff model. Rice model offered options for direct-seeding and transplanting of teff, cultivar-specific tillering effect, and the ability to simulate wide range of hydrologic regime from anaerobic flooded/saturated to aerobic upland conditions, all of which capture teff’s characteristics and growing conditions. The CERES- teff model as presented here simulated the effect of water, nitrogen, carbon dioxide, and daylength on crop growth and development. A concerted effort is needed to conduct knowledge-gap research on teff and evaluate teff model under a wide range of conditions. Teff can play greater role in food and nutritional security and as a climate resilient crop.
- ItemEconomic Feasibility of Alternative Technologies and Strategies for Sri Lanka’s Fertilizer Crisis: A Simulation Analysis for Paddy-Based Dry Zone Agricultural Systems(2024-08) Jeevika Weerahewa; Tharakabhanu de Alwis; Saman Dharmakeerthi; Latha Nagarajan; Zachary P. StewartThe government of Sri Lanka has introduced a mix of controversial fertilizer policies amid its economic crisis. The objective of this study is to assesses economic feasibility of a range of fertilizer technologies and strategies being introduced for paddy based dry zone agricultural systems of the country. A linear programming model was developed for a small paddy land holder considering maximization of profits as the objective and lowland and highland extents, labor, irrigation water, subsistence consumption, and financial resources allocated for fertilizers as constraints. The simulation scenarios included tax on urea-based fertilizers, increase in the cashgrant provided to farmers, innovative marketing arrangements for environmentally friendly products and innovative fertilizer technologies. The results of the simulation experiments provide some quantitative estimates on the magnitude of changes in farm enterprise profits, nitrogen usage by the crops, and wastage of nitrogen from the system owing to the policy changes. The simulation exercises underscored the positive impact of incorporating slow-releasing fertilizer types on farm enterprise profits and nitrogen wastage from the system, contingent upon the financial viability of such fertilizers. The study offers insights into the interplay of policy interventions in shaping the profitability and environmental dynamics of dry zone farming in Sri Lanka.
- ItemEffect of Waterlogging Duration on Teff [Eragrostis Tef (Zucc.) Trotter] Yield and Nutrient Uptake(2023-11-01) Mulugeta Demiss Belew; Upendra Singh; Zach Paul Stewart; Latha Nagarajan; Job FugiceTeff is considered tolerant to seasonal waterlogging. However, studies on the duration of waterlogging and its effects on yield and nutrient uptake of teff have not been conducted. A greenhouse study was conducted to investigate the impact of different waterlogging durations on growth, yield, and nutrient uptake of teff. Teff was subjected to waterlogging for 0 (control), 20, 40, and 60 days after transplanting (DAT) and for the entire growth period. The results showed that teff can tolerate waterlogging for the entire growth period without significant grain yield loss as long as there is sufficient nutrition. Grain yield for 20 DAT, 40 DAT, and the entire growth period treatments was lower than the control and 60 DAT showed an increase. Straw dry weight in the 40 DAT and entire growth period treatments was lower than the control, while that of the 20 DAT and 60 DAT treatments was higher. However, the differences in both straw and grain yields were not statistically significant among treatments. On the other hand, the treatment with waterlogging for the entire season had significantly greater root weight than the control treatment. Nutrient uptake data showed that N, P and K uptake reduced in grain and straw while their uptake increased in roots of teff as waterlogging duration increased. Application of the optimum amount of nutrients may contribute to the reduction in the detrimental effect of waterlogging on teff yield components. Understanding the regulation of root metabolism during waterlogging conditions, evaluating whether varietal differences in waterlogging tolerance exist, and identifying the physiological mechanisms that help teff tolerate waterlogging for longer durations need further study. The results will contribute to the prospects of developing improved germplasm for waterlogging tolerance. Validating the results under field conditions is recommended.
- ItemEfficient Fertilizer and Water management in Rice Cultivation for Food Security and Mitigating Greenhouse Gas Emissions(2018) Yam Kanta Gaihre; Upendra Singh; S.M. Mofijul Islam; Azmul Huda; M.R. Islam; Jatish Chandra BiswasIncreasing nitrogen fertilizer application has increased crop productivity and met the food demands of growing populations, but its use efficiency is very low. More than 50% of applied nitrogen is not utilized by crops, posing huge economic costs and environmental concerns. Therefore, fertilizer management should consider optimum source, rates, time, and methods of application (the “4Rs” of nutrient stewardship) to increase use efficiency, crop yield, soil health, and farm profits and to reduce negative environmental effects. Fertilizer deep placement (FDP) is one of the best currently applicable management techniques to achieve these multiple benefits. Multi-location experiments were conducted in Bangladesh to determine the effects of urea deep placement (UDP) and multi-nutrient fertilizer briquette (NPK) deep placement versus broadcast prilled urea (PU) on rice yields, nitrogen use efficiency, and nitrogen losses, including floodwater ammonium, ammonia volatilization, and nitrous oxide emissions. Deep placement of both urea and NPK briquettes in the dry (Boro) season increased grain yields. Across the years, the average observed yield increase was 30% compared to broadcast PU. Deep placement significantly reduced nitrogen losses compared to broadcast PU. Broadcast PU resulted in higher amounts of ammonium in floodwater and ammonia volatilization, both of which were negligible in deep-placed treatments. Moreover, UDP reduced nitrous oxide emissions by 70% as compared to broadcast PU. In Bangladesh, fertilizer briquettes are produced by micro-enterprises and applied manually in fields. This approach is effective in small-scale farming where household labor is sufficient for cultivation but requires modifications to work in larger scale farming systems where labor availability is an issue. Another issue relates to the nonavailability of fertilizer briquettes throughout the country. Therefore, for large-scale dissemination in other rice-growing countries in Asia, including China and India where greater N use efficiency gains can be realized, government and/or private sector actors must work together to promote wide-scale adoption by farmers through industrial-level briquette production and mechanized on-farm application.
- ItemEvaluation of Boron Produced As Seed-Core Urea for Urease Inhibition(2013-11) Upendra Singh; Job Fugice; Wendie D. Bible; Austin, E. Rick ; Joaquin SanabriaBorax (Na2B4O7.5 H2O) and boric acid (H3BO3) were evaluated as urease inhibitors by quantifying ammonia (NH3) volatilization loss under upland and flooded conditions. Boron-enriched urea was produced by two methods – compaction/tableting and seed-core granulation. The NH3 losses from the B products were compared with urea, urea + N-(n-butyl) thiophosphoric triamide (NBTPT) and urea + cyclohexyl phosphoric triamide (CHPT). The greenhouse study was conducted over a 17-day period and a 25-day period for the upland and flooded soils, respectively. The following year the experiment was repeated using freshly made and original products. Ammonia volatilization loss was a major N loss pathway under both the upland and flooded conditions accounting for losses of 34% and 51% of applied urea-N, respectively under the conditions of the experiment. The method of production of urea products containing B did not influence the NH3 volatilization loss. All B seed-core urea products were effective in reducing ammonia volatilization losses; however, when compared with urease inhibitors, NBTPT and CHPT, they were less effective. Under the upland condition, B seed-core urea gave as much as 37% lower NH3 volatilization loss than urea during the first 5 days, compared to only 17% lower volatilization loss after 17 days. Similar results of 37% and 10% lower NH3-N losses were obtained with flooded soil for first 5 days and after 15 days, respectively. Throughout the entire experimental period, losses of ammonia from soil treated with B seed-core urea were significantly lower than losses of ammonia from the same soils with urea applied alone. While there was no decline in the effectiveness of B seed-core urea products, the NBTPT product showed significant loss of activity during the 12-month storage period. Among the B products 0.5% B as boric acid was as effective as 2% B as borax in reducing volatilization losses. The single high rate of urea-N application (200 kg N ha-1) and the absence of a crop in this study may have influenced the effectiveness of B as a urease inhibitor, and most likely resulted in higher ammonia volatilization loss.