Vanlauwe B.,International Institute Of Tropical Agriculture |
Wendt J.,International Fertilizer Development Center |
Giller K.E.,Wageningen University |
Corbeels M.,CIRAD - Agricultural Research for Development |
And 2 more authors.
Field Crops Research | Year: 2014
Intensification of agricultural systems in sub-Saharan Africa (SSA) is considered a pre-condition for alleviation of rural poverty. Conservation Agriculture (CA) has been promoted to achieve this goal, based on three principles: minimum tillage, soil surface cover, and diversified crop rotations. CA originated in regions where fertilizer is commonly used and crop productivity is high, ensuring an abundance of crop residues. By contrast, crop yields are generally low in SSA and organic residues in short supply and farmers face competing demands for their use. Since minimal tillage without mulch commonly results in depressed yields, the use of fertilizer to enhance crop productivity and organic residue availability is essential for smallholder farmers to engage in CA. This is especially true since alternative ways to increase organic matter availability have largely failed. A case study from Kenya clearly demonstrates how fertilizer increases maize stover productivity above thresholds for minimal initial soil cover required for initiating CA (about 3tonneha-1). We conclude that strategies for using CA in SSA must integrate a fourth principle - the appropriate use of fertilizer - to increase the likelihood of benefits for smallholder farmers. © 2013 Elsevier B.V.
Wendt J.W.,International Fertilizer Development Center |
Hauser S.,International Institute Of Tropical Agriculture
European Journal of Soil Science | Year: 2013
Soil carbon stocks are commonly quantified at fixed depths as the product of soil bulk density, depth and organic carbon (OC) concentration. However, this method systematically overestimates OC stocks in treatments with greater bulk densities such as minimum tillage, exaggerating their benefits. Its use has compromised estimates of OC change where bulk densities differed between treatments or over time periods. We argue that its use should be discontinued and a considerable body of past research re-evaluated. Accurate OC estimations must be based on quantification in equivalent soil masses (ESMs). The objective of this publication is to encourage accurate quantification of changes in OC stocks and other soil properties using ESM procedures by developing a simple procedure to quantify OC in multiple soil layers. We explain errors inherent in fixed depth procedures and show how these errors are eliminated using ESM methods. We describe a new ESM procedure for calculating OC stocks in multiple soil layers and show that it can be implemented without bulk density sampling, which reduces sampling time and facilitates evaluations at greater depths, where bulk density sampling is difficult. A spreadsheet has been developed to facilitate calculations. A sample adjustment procedure is described to facilitate OC quantification in a single equivalent soil mass layer from the surface, when multiple-layer quantification is not necessary. © 2013 The Authors. Journal compilation © 2013 British Society of Soil Science.
Chien S.H.,International Fertilizer Development Center |
Gearhart M.M.,Honeywell |
Villagarcia S.,Agrarian National University
Soil Science | Year: 2011
Ammonium sulfate (AS) provides critical plant nitrogen (N) and sulfur (S) nutrients. Compared with other N fertilizers, such as urea and ammonium nitrate (AN), AS may have some potential agronomic and environmental benefits. These are (i) no potential toxicity of aqueous NH3 and nitrite to plants in alkaline soils; (ii) no N loss via NH 3 volatilization when surface applied to acid or neutral soils; (iii) a better N source for saline soils by decreasing the negative specific effects of NaCl on plant growth and for saline sodic calcareous soils by improving soil structure; (iv) positive effects of soil acidification on increasing availability of soil phosphorus (P) and applied phosphate rock and soil and applied micronutrients; (v) no contribution of CO 2 emission to greenhouse gases; (vi) a potential to use AS to reduce NH 3 volatilization from urea and enhance N efficiency of urea; (vii) more acidic root rhizosphere via preference absorption of NH 4-N of AS to NO 3-N of AN that may increase availability of soil P, applied phosphate rock, and micronutrients; (viii) less NO 3-N leaching from AS than AN can increase N efficiency and reduce NO 3-N pollution in groundwater and eventually drinking water; and (ix) less denitrification with AS than AN that may increase N efficiency and minimize greenhouse gases (NO and N 2O). Ammonium sulfate is more effective than granulated elemental S (ES) or ES-enriched NP fertilizers to provide S nutrient because AS is water soluble, whereas ES requires S oxidation to SO 4-S. The possible negative effects of AS compared with other N and S fertilizers are high soil acidification may require more liming and a higher cost per unit of N applied. However, the N cost of AS includes free S nutrient. Copyright © 2011 by Lippincott Williams & Wilkins.
Bindraban P.S.,United Virtual |
Dimkpa C.,United Virtual |
Nagarajan L.,International Fertilizer Development Center |
Roy A.,International Fertilizer Development Center |
Rabbinge R.,Wageningen University
Biology and Fertility of Soils | Year: 2015
Meeting human needs within the ecological limits of our planet calls for continuous reflection on, and redesigning of, agricultural technologies and practices. Such technologies include fertilisers, the discovery and use of which have been one of the key factors for increasing crop yield, agricultural productivity and food security. Fertiliser use comes, however, at an environmental cost, and fertilisers have also not been a very economically effective production factor to lift many poor farmers out of poverty, especially in African countries where application on poor soils of unbalanced compositions of nutrients in fertilisers has shown limited impact on yield increase. Agronomic practices to apply existing mineral fertilisers, primarily containing N, P and K, at the right time, the right place, in the right amount, and of the right composition can improve the use efficiency of fertilisers. However, the overall progress to reduce the negative side effects is inadequate for the desired transformation toward sustainable agriculture in poor countries. Globally, there have been no fundamental reflections about the role and functioning of mineral fertilisers over the past 5 decades or more, and compared to other sectors, dismal investments have been made in mineral fertiliser research and development (R&D). In this paper, we reflect on current fertilisers and propose a more deliberate adoption of knowledge of plant physiological processes—including the diversity of mineral nutrient uptake mechanisms, their translocation and metabolism—as an entry point in identifying the physicochemical “packaging” of nutrients, their composition, amount and timing of application to meet plant physiological needs for improved instantaneous uptake. In addition to delivery through the root, we suggest that efforts be redoubled with several other uptake avenues, which as of now are at best haphazard, for the delivery of nutrients to the plant, including above ground parts and seed coating. Furthermore, ecological processes, including nutrient-specific interactions in plant and soil, plant-microorganism symbiosis, and nanotechnology, have to be exploited to enhance nutrient uptake. It is hoped that concerted R&D efforts will be pursued to achieve these strategies. © 2015, The Author(s).
Agyin-Birikoran S.,International Fertilizer Development Center |
Newman Y.C.,University of Florida |
Kasozi G.N.,University of Florida
Crop Science | Year: 2012
Nitrogen is a critical element for sustainable for age production but N surpluses in sandy soils could result in nitrate leaching and water contamination. Our objective was to identify a N application rate that optimizes yield and quality of 'Tifton 85' bermudagrass (Cynodon Rich. spp.) with minimal N leaching losses in a typical Florida sandy soil. Four N application rates (30, 50, 70, and 90 kg N ha-1 per harvest) and an unfertilized (0 N) control in a Tifton 85 bermudagrass hay field were evaluated. Suction lysimeters were installed in each plot at 30 and 100 cm below the soil surface to measure soil water nitrate concentration. Nitrogen application at the recommended rate of 90 kg N ha-1 per harvest produced the greatest total dry matter yield (DMY) (~22 Mg ha-1 yr-1), but a modeled optimum DMY of ~18 Mg ha-1 yr-1 occurred at 57 kg N ha-1 per harvest. Nitrogen application increased herbage nutritive value, but the difference was not significant above 30 kg N ha-1 per harvest. Treatments with N rates ≤ 50 kg N ha-1 per harvest had leachate nitrate concentration below the maximum contaminant limit (MCL) of 10 mg L-1. However, N rates ≥ 70 kg N ha-1 per harvest had leachate nitrate concentration that exceeded the MCL, suggesting a risk of impacting groundwater quality. The results demonstrate that although Tifton 85 bermudagrass is an efficient N remover, there is potential for N leaching in sandy soils. Therefore, site-specific evaluation of appropriate N management is critical. © Crop Science Society of America.
Pray C.E.,Rutgers University |
Nagarajan L.,International Fertilizer Development Center
AgBioForum | Year: 2013
Biotechnology influenced Indian R&D through three channels: Bt cotton seed sales increased seed companies' income, providing them with money to invest in R&D and increasing their expectation for future profits from R&D; biosafety regulations increased biotech and seed firms' ability to capture some of the economic benefits from research by granting them a monopoly on GM traits and providing regulators to police the monopoly; finally, biotechnology improved technological opportunities with new traits and research tools. We tested the importance of these channels using an econometric model of R&D expenditure by the Indian seed industry with a unique set of individual firm data from 1987 to 2009. Our results show that the introduction of Bt cotton greatly increased seed sales and that these sales were the major determinant of R&D. Evidence also suggests that research increased due to technological opportunities created from GM traits and public-sector research. © 2013 AgBioForum.
Chien S.H.,International Fertilizer Development Center |
Rehm G.W.,University of Minnesota
Soil Research | Year: 2016
Efficiency of use of various phosphate fertilisers is affected by water-insoluble reaction products such as Fe-P, Al-P, and Ca-P in either discrete precipitates or surface-adsorbed forms. A product, maleic-itaconic acid copolymer, has been marketed for increasing efficiency of use of phosphate fertilisers. Field trials have been conducted to evaluate the agronomic effectiveness of this product with no measured positive effects. This absence of positive effects can be explained if fundamental principles of chemistry are considered. The negative logarithm of the equilibrium constant (pK) of CaHPO4.2H2O (DCPD) is higher than that of Ca-maleic acid and Ca-itaconic acid complexes. Therefore, the copolymers cannot prevent DCPD formation in calcareous soils. Likewise, because of the pK values of Fe-maleic, Fe-iticonic acid, Al-maleic acid, and Al-itaconic acid are lower than those values for AlPO4.2H2O, and FePO4.2H2O, the copolymer cannot block or prevent formation of AlPO4.2H2O and FePO4.2H2O in acid soils. The results of agronomic greenhouse and field trials can be explained by the considerations of the solubility-product constant or the dissociation constant of cation-chelate for various reactions. Therefore, the copolymer marketed has little value for increasing P efficiency from phosphate fertilisers as claimed by the manufacturer. Journal compilation. © CSIRO 2016.
News Article | February 16, 2017
CAPE TOWN, South Africa, Feb. 16, 2017 /PRNewswire/ -- Over 520 delegates gathered in Cape Town, South Africa, for the 8th annual Argus FMB Africa Fertilizer conference, bringing the biggest conference of its kind to southern Africa for the first time. The conference was organised by leading commodity price reporting, consulting and events company Argus. The conference was opened by South Africa's minister for agriculture, forestry and fisheries, Senzeni Zokwana. "Fertilizers play a leading role in the global food industry and fertilizer is the largest and most important component to ensure abundant and affordable food for a growing population," Zokwana said, in an opening address that reinforced the importance of collaboration across the supply chain. "I am thankful that Argus FMB has taken a leadership role in organising this conference. There is a need for a commitment from all of us to work together in addressing issues that are of mutual benefit." The conference agenda featured over 30 speakers who addressed ways to increase African farmers' access to fertilizer and consequently to boost agricultural yields across the continent. "We have been running this conference for many years," Argus Media chairman and chief executive Adrian Binks said, "but in the last 12 months we have seen a big surge in interest, in line with a renewal of political will to bring transformative changes to African agriculture." The other keynote speakers included OCP AFRICA chief executive Karim Lofti Senhadji, the African Development Bank's vice-president for agriculture, human and social development, Jennifer Blanke, and the chief executive of African development partnership NEPAD, Ibrahim Assane Mayaki. The conference is supported by the International Fertilizer Association (IFA), the Africa Fertilizer and Agribusiness Partnership (AFAP) and the International Fertilizer Development Center (IFDC) as well as by a number of other organisations involved in promoting fertilizer use in Africa. The agenda focused on increasing consumption of fertilizers and building meaningful supply chain partnerships in Africa. Speakers from the private and public sectors discussed the importance of creating enabling environments for fertilizer supply and distribution, improving access to finance and developing infrastructure that in turn will broaden intra-Africa trade, increase fertilizer consumption across the continent and ultimately boost agricultural productivity. "Argus FMB Africa Fertilizer has become known as the event that brings together the most important players in the global fertilizer trade with all the links in the African supply chain," Argus vice-president, conferences, David Monaghan said. "This conference has attracted delegates from 63 countries, of which 23 are African, and this number is going up every year, as we build on our commitment to increase access to the conference for the small-to-medium sized enterprises that are crucial to delivering appropriate and effective fertilizers to African farmers." Argus is collaborating with the West African Fertilizer Association (WAFA) to hold the West Africa Fertilizer Forum, which will take place on 9-10 May in Abidjan, Côte d'Ivoire. "West Africa is witnessing rapid growth in the development of its fertilizer market and this conference will focus on the specific opportunities and challenges in this region," Monaghan said. Argus conferences have provided opportunities to address issues of policy and regulation and uncover emerging trends in the fertilizer markets for over 30 years. They also provide a platform to meet and do business with leading global producers, traders and distributors. For more information about Argus FMB Africa Fertilizer 2017: Meeting dates: 15-17 February 2017 Venue: The Westin Cape Town, South Africa Contact: Laura Monk, Conference Marketing Manager Tel: +44 (0) 20 7780 4352 Email: firstname.lastname@example.org Visit: www.argusmedia.com/fertilizer-africa About Argus Media Argus is an independent media organisation with more than 800 staff. It is headquartered in London and has 21 offices in the world's principal commodity trading and production centres. Argus produces price assessments and analysis of international energy and other commodity markets, and offers bespoke consulting services and industry-leading conferences. Companies in 140 countries around the world use Argus data to index physical trade and as benchmarks in financial derivative markets as well as for analysis and planning purposes. Argus was founded in 1970 and is a privately held UK-registered company. It is owned by staff shareholders and global growth equity firm General Atlantic. In 2011 Argus purchased FMB Consultants Ltd (FMB), a provider of price reporting, market intelligence and events to the global fertilizer industry. ARGUS, the ARGUS logo, ARGUS MEDIA, ARGUS DIRECT, ARGUS OPEN MARKETS, AOM, FMB, DEWITT, JIM JORDAN & ASSOCIATES, JJ&A, FUNDALYTICS, METAL-PAGES, METALPRICES.COM, Argus publication titles and Argus index names are trademarks of Argus Media Limited.
Takeshima H.,International Food Policy Research Institute |
Nagarajan L.,International Fertilizer Development Center
Environment and Development Economics | Year: 2012
Although farmer market participation raises income, it often also reduces on-farm varietal diversity. However, for under-utilized crops like minor millets, market participation may actually encourage growers to increase on-farm diversity through better access to new varieties exchanged at local markets and higher returns from varieties already grown. We test this hypothesis in two different agro-ecological niches, the Plains and the Hills in southern India. Empirical results based on propensity score matching indicate that, in the less fertile dryland plains, market participation improved on-farm varietal diversity of minor millets and increased net revenues - albeit with insignificant welfare effects on farm households. On the other hand, in the fertile hill ecosystems, market development had no effect on varietal diversity. Insights from such a comparison could help design suitable policy interventions for on-farm conservation of under-utilized crops in their own agro-ecosystems through active stakeholder participation. © Copyright 2012 Cambridge University Press.
Singh U.,International Fertilizer Development Center |
Sanabria J.,International Fertilizer Development Center |
Austin E.R.,International Fertilizer Development Center |
Agyin-Birikorang S.,International Fertilizer Development Center
Soil Science Society of America Journal | Year: 2012
New N fertilizer products-organically enhanced NS plus and organically enhanced NS plus with Fe, manufactured by using sterilized and chemically converted organic additives extracted from municipal wastewater biosolids, were evaluated for N mineralization, ammonia (NH3-N) volatilization, N leaching, and effects on soil acidification, relative to urea. Laboratory incubations at three temperatures (20, 30, and 40°C), two leaching schemes (continuous and intermittent irrigation regimes), and ammonia volatilization experiments under aerobic (upland) and anaerobic (flooded) conditions were conducted in four appropriate soils (Greenville loam [fine, kaolinitic, thermic Rhodic Kandiudults], Lakeland sand [thermic, coated Typic Quartzipsamments], Guthrie silty-clay [fine-silty, siliceous, thermic Typic Fragiauults], and Sumter clay [fine-silty, carbonatic, thermic Rendollic Eutrudepts]). The two organically enhanced fertilizers had significantly lower nitrification than urea. At all three temperature levels in Greenville soil, the lag phase during the nitrification process was 28.6 d for organically enhanced fertilizers compared to 5.5 d for urea. The longer lag phase duration with organically enhanced fertilizers could result in reduced nitrate losses. Amending Guthrie soil with organically enhanced fertilizers had NH3-N volatilization losses (5 and 22% of applied N) significantly lower than those of the urea-fertilized Guthrie soil (33 and 58% of applied N) under aerobic and anaerobic conditions, respectively. Nitrate leaching with the two irrigation regimes in Lakeland sand was significantly lower for organically enhanced fertilizers than urea. Thus, the organically enhanced fertilizers could be an attractive N source. The environmental and food security benefits of organically enhanced fertilizers result from both recycling of sterilized and converted organic wastes (C, amino acids, and micronutrients) and minimizing the N losses from land to atmosphere and from land to water, which are characteristic of a disrupted N cycle and meet the standards on nutrient management set by NRCS. © Soil Science Society of America.