Crop Production (crop + production)

Distribution by Scientific Domains

Terms modified by Crop Production

  • crop production system

  • Selected Abstracts


    Policies, Interventions and Institutional Change in Pastoral Resource Management in Borana, Southern Ethiopia

    DEVELOPMENT POLICY REVIEW, Issue 4 2004
    Abdul B. Kamara
    The Borana rangelands of Southern Ethiopia are characterised by extensive livestock production under a communal land-use system that has evolved in response to variable rainfall and uncertain production conditions. However, the last two decades have witnessed an increasing privatisation of rangelands for crop production and private grazing. The results of a quantitative assessment are used to develop a framework for assessing the drivers of change and their long-term implications. It is concluded that certain national policies have resulted in conflicts of authority between traditional and formal systems, creating an avenue for spontaneous enclosures, associated conflicts and decreasing human welfare. [source]


    Perennialism and Poverty Reduction

    DEVELOPMENT POLICY REVIEW, Issue 1 2004
    Nigel D. Poole
    This article, which is both conceptual and a synthesis of the literature, considers the research component of poverty alleviation strategies for people whose livelihoods depend significantly on tree and forest resources. Two policy approaches are contrasted: enhancing the utilisation of indigenous tree species within the household and the local economy, and integrating tree and forest-dependent peoples into the wider economy by promoting the commercialisation of conventional tree crop production. It is argued that the discussion is relevant for other poor peoples who depend on perennial production systems, and that the conclusions contribute to the wider debate about remoteness, market access, decentralisation and targeting in policy formulation, and globalisation. [source]


    Whiteflies on tomato crops in Portugal,

    EPPO BULLETIN, Issue 1 2002
    A. Lopes
    In Portugal during the 1960/1980s, there was intensive development of vegetable crop production, in particular protected crops, of which tomato was the most important. The main producing regions now are Ribatejo e Oeste, Alentejo and Algarve. Tomato presents extensive phytosanitary problems, being host to a wide range of pests, including the whiteflies Trialeurodes vaporariorum, in protected crops, and Bemisia tabaci, in protected and field crops. Portugal has applied for the status of an EU ,protected zone' for this latter pest. As B. tabaci is an important vector of a large number of viruses, including tomato yellow leaf curl viruses (TYLCV), a monitoring programme of the tomato crop was implemented in Portugal. Preliminary data are presented concerning B. tabaci in the three main tomato-growing regions of the country. [source]


    An integrated biogeochemical and economic analysis of bioenergy crops in the Midwestern United States

    GCB BIOENERGY, Issue 5 2010
    ATUL K. JAIN
    Abstract This study integrates a biophysical model with a county-specific economic analysis of breakeven prices of bioenergy crop production to assess the biophysical and economic potential of biofuel production in the Midwestern United States. The bioenergy crops considered in this study include a genotype of Miscanthus, Miscanthus×giganteus, and the Cave-in-Rock breed of switchgrass (Panicum virgatum). The estimated average peak biomass yield for miscanthus in the Midwestern states ranges between 7 and 48 metric tons dry matter per hectare per year ( t DM ha,1 yr,1), while that for switchgrass is between 10 and 16 t DM ha,1 yr,1. With the exception of Minnesota and Wisconsin, where miscanthus yields are likely to be low due to cold soil temperatures, the yield of miscanthus is on average more than two times higher than yield of switchgrass. We find that the breakeven price, which includes the cost of producing the crop and the opportunity cost of land, of producing miscanthus ranges from $53 t,1 DM in Missouri to $153 t,1 DM in Minnesota in the low-cost scenario. Corresponding costs for switchgrass are $88 t,1 DM in Missouri to $144 t,1 DM in Minnesota. In the high-cost scenario, the lowest cost for miscanthus is $85 t,1 DM and for switchgrass is $118 t,1 DM, both in Missouri. These two scenarios differ in their assumptions about ease of establishing the perennial crops, nutrient requirements and harvesting costs and losses. The differences in the breakeven prices across states and across crops are mainly driven by bioenergy and row crop yields per hectare. Our results suggest that while high yields per unit of land of bioenergy crops are critical for the competitiveness of bioenergy feedstocks, the yields of the row crops they seek to displace are also an important consideration. Even high yielding crops, such as miscanthus, are likely to be economically attractive only in some locations in the Midwest given the high yields of corn and soybean in the region. [source]


    Atmospheric impact of bioenergy based on perennial crop (reed canary grass, Phalaris arundinaceae, L.) cultivation on a drained boreal organic soil

    GCB BIOENERGY, Issue 3 2010
    NARASINHA J. SHURPALI
    Abstract Marginal organic soils, abundant in the boreal region, are being increasingly used for bioenergy crop cultivation. Using long-term field experimental data on greenhouse gas (GHG) balance from a perennial bioenergy crop [reed canary grass (RCG), Phalaris arundinaceae L.] cultivated on a drained organic soil as an example, we show here for the first time that, with a proper cultivation and land-use practice, environmentally sound bioenergy production is possible on these problematic soil types. We performed a life cycle assessment (LCA) for RCG on this organic soil. We found that, on an average, this system produces 40% less CO2 -equivalents per MWh of energy in comparison with a conventional energy source such as coal. Climatic conditions regulating the RCG carbon exchange processes have a high impact on the benefits from this bioenergy production system. Under appropriate hydrological conditions, this system can even be carbon-negative. An LCA sensitivity analysis revealed that net ecosystem CO2 exchange and crop yield are the major LCA components, while non-CO2 GHG emissions and costs associated with crop production are the minor ones. Net bioenergy GHG emissions resulting from restricted net CO2 uptake and low crop yields, due to climatic and moisture stress during dry years, were comparable with coal emissions. However, net bioenergy emissions during wet years with high net uptake and crop yield were only a third of the coal emissions. As long-term experimental data on GHG balance of bioenergy production are scarce, scientific data stemming from field experiments are needed in shaping renewable energy source policies. [source]


    Contribution of N2O to the greenhouse gas balance of first-generation biofuels

    GLOBAL CHANGE BIOLOGY, Issue 1 2009
    EDWARD M. W. SMEETS
    Abstract In this study, we analyze the impact of fertilizer- and manure-induced N2O emissions due to energy crop production on the reduction of greenhouse gas (GHG) emissions when conventional transportation fuels are replaced by first-generation biofuels (also taking account of other GHG emissions during the entire life cycle). We calculate the nitrous oxide (N2O) emissions by applying a statistical model that uses spatial data on climate and soil. For the land use that is assumed to be replaced by energy crop production (the ,reference land-use system'), we explore a variety of options, the most important of which are cropland for food production, grassland, and natural vegetation. Calculations are also done in the case that emissions due to energy crop production are fully additional and thus no reference is considered. The results are combined with data on other emissions due to biofuels production that are derived from existing studies, resulting in total GHG emission reduction potentials for major biofuels compared with conventional fuels. The results show that N2O emissions can have an important impact on the overall GHG balance of biofuels, though there are large uncertainties. The most important ones are those in the statistical model and the GHG emissions not related to land use. Ethanol produced from sugar cane and sugar beet are relatively robust GHG savers: these biofuels change the GHG emissions by ,103% to ,60% (sugar cane) and ,58% to ,17% (sugar beet), compared with conventional transportation fuels and depending on the reference land-use system that is considered. The use of diesel from palm fruit also results in a relatively constant and substantial change of the GHG emissions by ,75% to ,39%. For corn and wheat ethanol, the figures are ,38% to 11% and ,107% to 53%, respectively. Rapeseed diesel changes the GHG emissions by ,81% to 72% and soybean diesel by ,111% to 44%. Optimized crop management, which involves the use of state-of-the-art agricultural technologies combined with an optimized fertilization regime and the use of nitrification inhibitors, can reduce N2O emissions substantially and change the GHG emissions by up to ,135 percent points (pp) compared with conventional management. However, the uncertainties in the statistical N2O emission model and in the data on non-land-use GHG emissions due to biofuels production are large; they can change the GHG emission reduction by between ,152 and 87 pp. [source]


    Nutrient constraints to tropical agroecosystem productivity in long-term degrading soils

    GLOBAL CHANGE BIOLOGY, Issue 12 2008
    SOLOMON NGOZE
    Abstract Soil degradation is one of the most serious threats to sustainable crop production in many tropical agroecosystems where extensification rather than intensification of agriculture has occurred. In the highlands of western Kenya, we investigated soil nitrogen (N) and phosphorus (P) constraints to maize productivity across a cultivation chronosequence in which land-use history ranged from recent conversion from primary forest to 100 years in continuous cropping. Nutrient treatments included a range of N and P fertilizer rates applied separately and in combination. Maize productivity without fertilizer was used as a proxy measure for indigenous soil fertility (ISF). Soil pools of mineral nitrogen, strongly bound P and plant-available P decreased by 82%, 31% and 36%, and P adsorption capacity increased by 51% after 100 years of continuous cultivation. For the long rainy season (LR), grain yield without fertilizer declined rapidly as cultivation age increased from 0 to 25 years and then gradually declined to a yield of 1.6 Mg ha,1, which was maintained as time under cultivation increased from 60 to 100 years. LR grain yield in the old conversions was only 24% of the average young conversion grain yield (6.4 Mg ha,1). Application of either N or P alone significantly increased grain yield in both the LR and short rainy (SR) seasons, but only application of 120 kg N ha,1 on the old conversion increased yield by >1 Mg ha,1. In both SR and LR, there was a greater average yield increment response to N and P when applied together (ranging from 1 to 3.8 Mg ha,1 for the LR), with the greatest responses on the old conversions. The benefit,cost ratio (BCR) for applying 120 kg N ha,1 alone was <1 except on the old conversions, while BCRs were>1 for applying 25 kg P ha,1 alone at all levels of conversion for both seasons. Application of both N (120 kg N ha,1) and P (25 kg P ha,1) on the old conversions resulted in the greatest BCRs. This study clearly indicates that maize productivity responses to N and P fertilizer are significantly affected by the age of cultivation and its influence on ISF, but that loss of productivity can be restored rapidly when these limiting nutrients are applied. Management strategies should consider ISF and economic factors to determine optimal N and P input requirements for achieving and sustaining profitable crop production on degraded soils. [source]


    Will photosynthesis of maize (Zea mays) in the US Corn Belt increase in future [CO2] rich atmospheres?

    GLOBAL CHANGE BIOLOGY, Issue 6 2004
    An analysis of diurnal courses of CO2 uptake under free-air concentration enrichment (FACE)
    Abstract The C4 grass Zea mays (maize or corn) is the third most important food crop globally in terms of production and demand is predicted to increase 45% from 1997 to 2020. However, the effects of rising [CO2] upon C4 plants, and Z. mays specifically, are not sufficiently understood to allow accurate predictions of future crop production. A rainfed, field experiment utilizing free-air concentration enrichment (FACE) technology in the primary area of global corn production (US Corn Belt) was undertaken to determine the effects of elevated [CO2] on corn. FACE technology allows experimental treatments to be imposed upon a complete soil,plant,atmosphere continuum with none of the effects of experimental enclosures on plant microclimate. Crop performance was compared at ambient [CO2] (354 , mol mol,1) and the elevated [CO2] (549 ,mol mol,1) predicted for 2050. Previous laboratory studies suggest that under favorable growing conditions C4 photosynthesis is not typically enhanced by elevated [CO2]. However, stomatal conductance and transpiration are decreased, which can indirectly increase photosynthesis in dry climates. Given the deep soils and relatively high rainfall of the US Corn Belt, it was predicted that photosynthesis would not be enhanced by elevated [CO2]. The diurnal course of gas exchange of upper canopy leaves was measured in situ across the growing season of 2002. Contrary to the prediction, growth at elevated [CO2] significantly increased leaf photosynthetic CO2 uptake rate (A) by up to 41%, and 10% on average. Greater A was associated with greater intercellular [CO2], lower stomatal conductance and lower transpiration. Summer rainfall during 2002 was very close to the 50-year average for this site, indicating that the year was not atypical or a drought year. The results call for a reassessment of the established view that C4 photosynthesis is insensitive to elevated [CO2] under favorable growing conditions and that the production potential of corn in the US Corn Belt will not be affected by the global rise in [CO2]. [source]


    Forage and biomass feedstock production from hybrid forage sorghum and sorghum,sudangrass hybrids

    GRASSLAND SCIENCE, Issue 4 2008
    Brad Venuto
    Abstract As the bioenergy industry expands, producers choosing to shift current forage crop production to dedicated biomass crops can benefit from growing lower risk multipurpose crops that maximize management options. Hybrid forage sorghums (HFS) and sorghum,sudangrass hybrids (SSG) are capable of impressive biomass yields and tolerance to environmental stress. Multiple vegetative harvests (ratoon harvests) of sorghum are possible and there are photoperiod-sensitive sorghums that remain vegetative. However, the response of newer HFS and SSG cultivars to harvest management practices designed for forage or cellulosic feedstock production has not been fully investigated in all environments. The objectives of this study were to: (i) determine biomass production and quality characteristics of a genetically diverse range of HFS, SSG and sudangrass cultivars and evaluate their interaction with harvest system; and (ii) provide data to aid selection of sorghum cultivars for both forage and biofuel uses. Mean yield across all entries and years for a single late season harvest was 27.1 Mg ha,1 of dry matter per year. Mean total yield for a first harvest plus a ratoon crop was 25.5 Mg ha,1 of dry matter per year. However, entries varied for yield and interacted with harvest system. Mean caloric value was 16.5 Gj Mg,1 and modest differences were observed among cultivars evaluated. The best performing entry (cv. Tentaka) yielded 40.3 Mg ha,1 of dry matter for a single late season harvest, demonstrating the biomass potential of existing sorghum cultivars, specifically those possessing photoperiod- and/or thermosensitive genotypes. [source]


    Simulation of groundwater dynamics in the North China Plain by coupled hydrology and agricultural models

    HYDROLOGICAL PROCESSES, Issue 16 2006
    Tadanobu Nakayama
    Abstract We simulated the effects of irrigation on groundwater flow dynamics in the North China Plain by coupling the NIES Integrated Catchment-based Ecohydrology (NICE) model with DSSAT-wheat and DSSAT-maize, two agricultural models. This combined model (NICE-AGR) was applied to the Hai River catchment and the lower reach of the Yellow River (530 km wide by 840 km long) at a resolution of 5 km. It reproduced excellently the soil moisture, evapotranspiration and crop production of summer maize and winter wheat, correctly estimating crop water use. So, the spatial distribution of crop water use was reasonably estimated at daily steps in the simulation area. In particular, NICE-AGR reproduced groundwater levels better than the use of statistical water use data. This indicates that NICE-AGR does not need detailed statistical data on water use, making it very powerful for evaluating and estimating the water dynamics of catchments with little statistical data on seasonal water use. Furthermore, the simulation reproduced the spatial distribution of groundwater level in 1987 and 1988 in the Hebei Plain, showing a major reduction of groundwater level due mainly to overpumping for irrigation. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    Economic Liberalization and Smallholder Productivity in Tanzania.

    JOURNAL OF AGRARIAN CHANGE, Issue 3 2005
    From Promised Success to Real Failure
    In the mid-1980s, Tanzania adopted a programme for economic liberalization of the entire economy, including agriculture. After pressure from the IMF and the World Bank in particular, but also from most of the bilateral donors, agricultural producer and input prices were decontrolled, panterritorial prices were abolished, subsidies were removed and trade in agricultural products and inputs was to a large extent taken over by private traders. The international donor community promised that economic liberalization would provide a strong stimulus to Tanzanian agriculture, resulting in increasing yields, increased labour productivity, rising agricultural production and higher incomes. However, available data show that, as far as food crop production is concerned, this promise has not been fulfilled. Even compared to the ,crisis years' 1979,1984, labour productivity, yields and production per capita of food grains stagnated or declined up to the end of the 1990s. Some causes of this failure are discussed. [source]


    Exogenous Glycinebetaine and Salicylic Acid Application Improves Water Relations, Allometry and Quality of Hybrid Sunflower under Water Deficit Conditions

    JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 2 2009
    M. Hussain
    Abstract Limited water availability hampers the sustainability of crop production. Exogenous application of glycinebetaine (GB) and salicylic acid (SA) has been found very effective in reducing the adverse effects of water scarcity. This study was conducted to examine the possible role of exogenous GB and SA application in improving the growth and water relations of hybrid sunflower (Helianthus annuus L.) under different irrigation regimes. There were three levels of irrigation, viz. control (normal irrigations), water stress at budding stage (irrigation missing at budding stage) and water stress at flowering stage (FS) (irrigation missing at FS). GB and SA were applied exogenously at 100 and 0.724 mm respectively, each at the budding and FS. Control plants did not receive application of GB and SA. Water stress reduced the leaf area index (LAI), leaf area duration (LAD), crop growth rate (CGR), leaf relative water contents, water potential, osmotic potential, turgor pressure, achene yield and water use efficiency. Nevertheless, exogenous GB and SA application appreciably improved these attributes under water stress. However, exogenous GB application at the FS was more effective than other treatments. Net assimilation rate was not affected by water stress as well as application of GB and SA. The protein contents were considerably increased by water stress at different growth stages, but were reduced by exogenous GB and SA application. The effects of water stress and foliar application of GB were more pronounced when applied at FS than at the budding stage. Moreover, exogenous GB application was only advantageous under stress conditions. [source]


    Improving Drought Tolerance by Exogenous Application of Glycinebetaine and Salicylic Acid in Sunflower

    JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2008
    M. Hussain
    Abstract Water shortage is a severe threat to the sustainability of crop production. Exogenous application of glycinebetaine (GB) and salicylic acid (SA) has been found very effective in reducing the adverse affects of drought stress. This study was conducted to examine the possible role of exogenous GB and SA application in improving the yield of hybrid sunflower (Helianthus annuus L.) under different irrigation regimes. There were three levels of irrigation, viz. control (normal irrigations), water stress at vegetative stage (irrigation missing at vegetative stage) and water stress at flowering stage (irrigation missing at flowering stage). GB and SA were applied exogenously at 100 and 0.724 mm, respectively, each at the vegetative and at the flowering stage. Control plants did not receive application of GB and SA. Water stress reduced the head diameter, number of achene, 1000-achene weight, achene yield and oil yield. Nevertheless, exogenous GB and SA application significantly improved these attributes under water stress. However, drought stress increased the free leaf proline and GB, and were further increased by exogenous application of GB and SA. However, exogenous GB application at the flowering stage was more effective than other treatments. Oil contents were also reduced under water stress; however, GB and SA application could not ameliorate the negative effect of water stress on achene oil contents. The effects of water stress and foliar application of GB were more pronounced when applied at the flowering stage than at the vegetative stage. Moreover, exogenous GB application was only beneficial under stress conditions. [source]


    Competitive dynamics in two- and three-component intercrops

    JOURNAL OF APPLIED ECOLOGY, Issue 3 2007
    METTE KLINDT ANDERSEN
    Summary 1Intercropping is receiving increasing attention because it offers potential advantages for resource utilization, decreased inputs and increased sustainability in crop production, but our understanding of the interactions among intercropped species is still very limited. 2We grew pea Pisum sativum, barley Hordeum vulgare and rape Brassica napus as sole crops and intercrops under field conditions using a replacement design. We collected total dry matter data from sequential harvests and fitted the data to a logistic growth model. At each harvest we estimated the relative Competitive Strength (CS) of the three crops by fitting the data to a simple interspecific competition model. 3The pea monocrop produced the largest amount of biomass from the middle to the end of the growth period, but pea was not dominant in intercrops. 4Fitting data to a logistic growth model emphasizes the importance of initial size differences for interactions among intercrops. Barley was the dominant component of the intercrops largely because of its initial size advantage. The competitive effect of barley on its companion crops, measured as CS, increased throughout most of the growing season. 5The performance of each crop species was very different when it grew with a second species rather than in monoculture, but addition of a third crop species had only minor effects on behaviour of the individual crops. 6Synthesis and applications. Including sequential harvests in experiments on intercropping can provide important information about how competitive hierarchies are established and change over time. Our results suggest that increased understanding of the role of asymmetric competition among species and the resulting advantages of early germination and seedling emergence would be valuable in designing intercrops. More focus on understanding the mechanisms that govern interactions between intercropped species is needed for designing optimized intercropping systems. [source]


    Plant growth promotion and biological control of Pythium aphanidermatum, a pathogen of cucumber, by endophytic actinomycetes

    JOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2009
    K.A. El-Tarabily
    Abstract Aims:, To evaluate the potential of Actinoplanes campanulatus, Micromonospora chalcea and Streptomyces spiralis endophytic in cucumber roots, to promote plant growth and to protect seedlings and mature plants of cucumber from diseases caused by Pythium aphanidermatum, under greenhouse conditions. Methods and Results:, Three endophytic isolates, out of 29, were selected through tests aimed at understanding their mechanisms of action as biocontrol agents and plant growth promoters. When applied individually or in combination, they significantly promoted plant growth and reduced damping-off and crown and root rot of cucumber. The combination of the three isolates resulted in significantly better suppression of diseases and plant growth promotion, than where the plants were exposed to individual strains. Conclusions:, The three selected actinomycete isolates colonized cucumber roots endophytically for 8 weeks, promoted plant growth and suppressed pathogenic activities of P. aphanidermatum on seedling and mature cucumber plants. Significance and Impact of the Study:, The results clearly show that the endophytic, glucanase-producing actinomycetes used, especially as a combined treatment, could replace metalaxyl, which is the currently recommended fungicide for Pythium diseases in the United Arab Emirates. These endophytic isolates also have the potential to perform as plant growth promoters, which is a useful attribute for crop production in nutrient impoverished soils. [source]


    Impact of eucalyptus and pine growing on rural livelihood: the lesson from Bukoba area, north western Tanzania

    AFRICAN JOURNAL OF ECOLOGY, Issue 2009
    Phillip K. MwanukuziArticle first published online: 3 FEB 200
    Abstract Sustainable resource management intends to allocate resources in such a way that unnecessary deterioration of biophysical and socio-economical systems is avoided. In Bukoba Area where rainfalls are plenty, evergreen grasslands were expansive and forests were limited, eucalypts (eucalyptus spp.) and pines (pinus spp.) were grown on grasslands for preventing land degradation through deforestation and for providing additional source of income for rural poor. This study shows that in addition to detrimental consequence of eucalyptus and pine forests on soil resources, conversion of Bukoban grasslands to forests has negatively impacted livelihood of the rural poor. Growing eucalypts and pines on grasslands prevented a farming system that enabled integration of grasslands, cattle keeping and crop production. Consequently, the grasslands role of nutrients cycling was disrupted, food crop production reduced, home-gardens productivity declined, majority deprived important livelihood asset and foreign income flow into the area reduced. [source]


    Wetlands, livelihoods and sustainability in Tanzania

    AFRICAN JOURNAL OF ECOLOGY, Issue 2009
    A. G. Mwakaje
    Abstract Wetlands in Tanzania are among the world's most biologically productive ecosystems and are rich in species diversity. Wetlands support family livelihoods through crop production, grazing pastures and direct resource extractions. Ecologically, wetlands are instrumental in water storage, filtration, flood control and toxic retention and are also important habitat for biodiversity both flora and fauna. The last 30 years have witnessed rapid degradation of wetlands which threatens livelihoods; disturbs ecological settings and leads into unsustainable development. In this study, an attempt has been made to describe the livelihoods and sustainability issues of the Bahi Wetlands in Central Tanzania. This is a semi-arid area and therefore the wetland plays a key role socio-economically and environmentally. Data were collected from 200 households in Ngaiti and Kitalalo villages using structured and semi-structured questionnaires. There were also focused groups interviews, key informants and Participatory Rural Appraisal methods. Findings show Bahi Wetlands to play a significant role in livelihoods, cultural and ecological functions. However, the sustainability of the wetlands is threatened by over-cultivation, overgrazing and over-extraction of natural resources directly. Livelihood diversifications through credit provision, improved extension services and strengthened local institutions, are recommended. Wetlands policy and laws should be developed and enforced. [source]


    An econometric analysis of regional adoption patterns of Bt maize in Germany

    AGRICULTURAL ECONOMICS, Issue 3-4 2010
    Nicola Consmüller
    Bt maize; Genetically modified organisms (GMO); Germany; Panel data analysis Abstract In this study, our goal is to identify and explain the underlying factors that drive regional adoption of Bt maize MON810 in Germany. Since regional differences cannot be explained by the occurrence of the target pest alone, we assume that under the given regulatory framework for genetically modified (GM) crop production in Germany, farm structures as well as the sociopolitical environment have also influenced regional adoption rates during the past years. Following a description of the relevant legal and economic framework in Germany, we develop theoretical hypotheses for regional variation in Bt maize adoption and test them econometrically with unique data at the federal state (Laender) and county (Landkreis) level. According to our analysis at the federal state level, the maize acreage per farm is the main driver of Bt maize adoption. In addition, there are signs that public opposition to GM cultivation as measured by membership in the German Friends of the Earth association significantly dampens GM cultivation. At the level of Brandenburg counties, the regional infestation frequency of the European Corn Borer, the target pest of Bt-Maize, is the major determinant of adoption. Although Bt maize is a scale-neutral technology for controlling damages caused by the Corn Borer, additional fixed costs due to regulation make the technology scale dependent. [source]


    Rural nonfarm activities and agricultural crop production in Nigeria

    AGRICULTURAL ECONOMICS, Issue 2 2009
    Gbemisola Oseni
    Nigeria; Rural nonfarm activities; Agricultural crop expenditures; Credit constraints Abstract Although most rural households are involved in the farm sector, the nonfarm sector has grown significantly in recent decades, and its role in rural development has become increasingly important. This article examines the effect of participation in nonfarm activities on crop expenses of farm households in Nigeria. The relationship is modeled using a nonseparable agricultural household model that suggests that participating in nonfarm activities can relax the credit constraints facing farm households and reduce risk thereby helping households improve farm production and smooth consumption over time. The results show that participation in nonfarm activities by Nigerian farmers has a positive and significant effect on crop expenses and in particular on payments for hired labor and inorganic fertilizers. Separate analysis of the six geopolitical zones in Nigeria indicates that it is in the South-South and South-East zones where nonfarm participation appears to induce more hiring of labor. The results support the hypothesis that nonfarm participation helps relax liquidity constraints but suggests how that liquidity is used is zone-specific. In general, the results also indicate that liquidity is used more to pay for inputs into staple production as opposed to cash crops. [source]


    Walnut Staminate Flowers Can Be Explored as a Supplementary Plant Oil Source

    JOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 4 2006
    Husen Jia
    Abstract Fossil fuel is currently the major energy source driving global socio-economy, but its stock is being heavily depleted due to increasing anthropogenic activities worldwide. There are also concerns regarding the burning of fossil fuels, which contributes to global climate warming and air pollution. As such, the development of biodiesel as a non-toxic, biodegradable, and renewable alternative energy source using oil crops such as soybean and rapeseed has quickly emerged in the West countries. However, the production of oil crops in China is far from sufficient to meet the demands of the country's population of 1.3 billion, and increasing oil crop production is inhibited by a severe shortage of agricultural land, which currently averages 0.2 acre per person and, as such, is less than half the world average. The current national policy in China regarding land use is more towards revering cultivated lands in ravins and hills to forestry, which presents an ideal opportunity to further develop plantations of walnut (Juglans regia L.) trees, a plant that is tolerant to drought and infertile soils and has a high oil content. Study in this paper shows that one ament of walnut staminate flowers produces about 0.168 g dry pollen, and the dry pollen contained 49.67% oil. Based on this discovery, oil yield obtained from staminate flowers is estimated to reach 6.95% of that from walnut nuts. Thus walnut staminate flower is suggested to explore as supplementary plant oil source, and has a great opportunity to utilize as a biodiesel feedstock. (Managing editor: Wei Wang) [source]


    Cultivation of flax in spoil-bank clay: Mycorrhizal inoculation vs. high organic amendments

    JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 6 2008
    David Püschel
    Abstract A greenhouse experiment was focused on the application of arbuscular mycorrhizal fungi (AMF) in effective crop production during reclamation of coal-mine spoil banks. The aim of the study was to find out whether mycorrhizal inoculation improves growth of flax (Linum usitatissimum L.) and whether it can compensate for high doses of expensive organic amendment. Flax was planted in original spoil-bank gray Miocene clay amended with organic matter used for spoil-bank reclamation (mixture of composted urban waste and lignocellulose papermill waste). This amendment was applied in four descending doses equivalent to the application of 500, 200, 100, and 0 t ha,1. The plants received either a mixed inoculum of three AMF species (Glomus mosseae, G. claroideum, and G. intraradices) or were left uninoculated. Growth of flax was significantly increased by mycorrhizal inoculation in pure clay (by 60%) as well as in clay with all amendment doses (by 119% on average). Also, the addition of organic matter increased plant growth but, interestingly, the biomass production was comparable regardless the dose of amendment. Our results suggest that similar yields are attainable with only one fifth of the usual fertilization dose, which can significantly decrease costs related to the reclamation of spoil banks. If mycorrhizal inoculation is applied together with the optimized fertilization, growth of flax planted in spoil-bank clay can be further improved. [source]


    Effects of nitrogen supply on water-use efficiency of higher plants

    JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 2 2008
    Holger Brueck
    Abstract The worldwide increase of food demand and reduced sweet-water availability in some important food-producing regions raised interest in more efficient water use, which has become one of the central research topics in agriculture. Improved irrigation management and reduced bare-soil evaporation have highest priority to increase agronomic water-use efficiency (WUE). Compared to these technical (irrigation) and basic (crop production) management options, effects of nutrient management on WUE were less frequently considered. Twenty-nine publications on nitrogen (N) effects on biomass WUE of container-grown plants are considered in this review. Most of them indicate positive N effects on WUE, and relevance of N effects on intrinsic WUE and unproductive water and carbon loss is discussed. A plot of 90 published data of percent decreases of WUE and dry mass under variable N supply is presented. Extrapolation of biomass WUE from leaf measurements of intrinsic WUE is critically reviewed. The positive correlation between WUE and dry-mass formation suggests that physiological rather than stomatal effects are more important in order to explain positive N effects on WUE. [source]


    Compositional nutrient diagnosis and main nutrient interactions in yellow pepper grown on desert calcareous soils

    JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2004
    José Luis García-Hernández
    Abstract Mineral-nutrient stress is one of the main factors limiting crop production, especially in arid lands. The mineral requirement of a crop is difficult to determine, and the interpretation of foliar chemistry composition is not easy. This study was conducted to compute the minimum yield target for fresh fruit of yellow pepper (Capsicum annuum L.) and the corresponding Compositional Nutrient Diagnosis (CND) as well as to identify significant nutrient interactions of this crop in desert calcareous soils. Preliminary CND norms were developed using a cumulative variance-ratio function and the chi-square distribution function. From a small database, we computed means and standard deviations of row-centered log ratios, VX, of five nutrients (N, P, K, Ca, and Mg) and a filling value, R, which comprises all nutrients not chemically analyzed and quantified them in 54 foliar samples of the popular yellow pepper cv. ,Santa Fé'. This cultivar is widely grown in northwest Mexico under arid conditions. These norms are associated to fresh fruit yields higher than 15.04 t ha,1. Principal-component analyses, performed using estimated CND nutrient indexes, allowed us to identify four interactions: negative P-Ca, P-Mg, and N-K, and positive Ca-Mg. Pepper plants growing on calcareous soils tend to take up more Ca and Mg than considered as optimum in other soil conditions. [source]


    The Bayesian choice of crop variety and fertilizer dose

    JOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES C (APPLIED STATISTICS), Issue 1 2002
    Chris M Theobald
    Recent contributions to the theory of optimizing fertilizer doses in agricultural crop production have introduced Bayesian ideas to incorporate information on crop yield from several environments and on soil nutrients from a soil test, but they have not used a fully Bayesian formulation. We present such a formulation and demonstrate how the resulting Bayes decision procedure can be evaluated in practice by using Markov chain Monte Carlo methods. The approach incorporates expert knowledge of the crop and of regional and local soil conditions and allows a choice of crop variety as well as of fertilizer level. Alternative dose,response functions are expressed in terms of a common interpretable set of parameters to facilitate model comparisons and the specification of prior distributions. The approach is illustrated with a set of yield data from spring barley nitrogen,response trials and is found to be robust to changes in the dose,response function and the prior distribution for indigenous soil nitrogen. [source]


    Time for a shift in crop production: embracing complexity through diversity at all levels

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2009
    Hanne Řstergĺrd
    A radical shift in our approach to crop production is needed to ensure food security and to address the problems of soil degradation, loss of biodiversity, polluted and restricted water supplies, coupled with a future of fossil fuel limitations and increasingly variable climatic conditions. An interdisciplinary network of European scientists put forward visions for future crop production embracing the complexity of our socio-ecological system by applying the principle of diversity at all levels from soil micro-organisms to plant varieties and cropping systems. This approach, integrated with careful deployment of our finite global resources and implementation of appropriate sustainable technology, appears to be the only way to ensure the scale of system resilience needed to cope with many of our concerns. We discuss some of the most important tools such as (i) building soil fertility by recycling of nutrients and sustainable use of other natural and physical resources, (ii) enhancing biological diversity by breeding of crops resilient to climate change and (iii) reconnecting all stakeholders in crop production. Finally, we emphasise some of the changes in agricultural and environmental regulation and policy needed in order to implement the visions. Copyright © 2009 Society of Chemical Industry [source]


    Comparative effect of biofertilizers on fodder production and quality in guinea grass (Panicum maximum Jacq.)

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2008
    Seema Mishra
    Abstract BACKGROUND:Panicum maximum Jacq. is one of the most important fodder grasses of the tropics. For good production and growth it requires high amounts of N fertilizer. Chemical fertilizers have a deleterious effect on soil fertility and are not economical for resource-poor farmers. Utilization of plant growth-promoting bacteria and fungi proved to be beneficial for improving crop production as well as the soil fertility. In the present paper the effect of inoculation of N fixer (Azospirillum brasilense) and P solubilizers (arbuscular mycorrhizal (AM) fungi consortia and inoculum of Glomus intraradiaces) was studied in single as well as mixed inoculation on forage yield and quality in guinea grass (Panicum maximum Jacq.) at different cuttings under the cut-and-carry system. RESULTS: Overall five cuttings were obtained during the year. Dual inoculation, i.e., Azospirillum with indigenous AM consortia, significantly improved fodder growth, production and quality in terms of crude protein (CP) content, while neutral detergent fiber (NDF) and acid detergent fiber (ADF) content decreased after this treatment. The density of soil microbes (number of Azospirillum colony-forming units, number of AM spores) was enhanced in mixed inoculation. Chemical fertilizer improved fodder production and CP content significantly over control but also enhanced NDF and ADF content and suppressed the Azospirillum colony-forming units, AM spores and AM root infection. CONCLUSION: It could be concluded from the present study that inoculated N fixer and P solubilizer have a synergistic effect which enhanced overall fodder production, quality and also beneficial microflora in the rhizosphere soil, which also demonstrated the sustainability of biofertilizers. Copyright © 2008 Society of Chemical Industry [source]


    Rising carbon dioxide concentrations and the future of crop production

    JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2006
    Arnold J Bloom
    No abstract is available for this article. [source]


    Diversification of rural livelihood strategies and its effect on local landscape restoration in the semiarid hilly area of the Loess Plateau, China

    LAND DEGRADATION AND DEVELOPMENT, Issue 5 2010
    L. Wang
    Abstract This study is about the diversification of livelihood strategies and the interaction of farmers' livelihood with landscape change in Zhongzhuang small watershed, Pengyang County in Ningxia Autonomous region located in the Loess Plateau, western China. Farmers' livelihoods and landscape patterns during 1978,2007 in Zhongzhuang were analysed. In different stages, diverse limiting factors were discovered behind the diversification process of livelihood strategies. Before 1978, ,planned economy', ,production team organization', strict ,household registration system' and the scarcity of livelihood assets were the main factors restricting the diversification of livelihood strategies. From 1978 to 1993, the reform and open policy provided opportunities for local people to diversify their livelihood strategies, but livelihood strategies based on crop production still took an important role in their life. From 2000 to 2007, national policies brought assistance to help local farmers diversify their agricultural activities. However, the insufficient and incomplete credit and insurance market and lack of skill were the main factors constraining non-farm activity diversification. Meanwhile, through analysis of the links between livelihood strategies diversification and landscape pattern change, we found that diversification of farmers' livelihoods contributed to the recovery of the landscape. Finally, using this relationship, steps for future landscape restoration is proposed, which provide a new view of landscape restoration research in the Loess Plateau. Copyright © 2010 John Wiley & Sons, Ltd. [source]


    Sediment-bound nutrient export from micro-dam catchments in Northern Ethiopia

    LAND DEGRADATION AND DEVELOPMENT, Issue 2 2008
    N. Haregeweyn
    Abstract The losses in soil nutrients (nitrogen (N), available phosphorus (Pav), organic carbon (OC), potassium (K), calcium (Ca) and magnesium (Mg)) in the catchment and the storage in the reservoir as a result of sediment delivery were assessed in 13 catchments/reservoirs in Tigray, Northern Ethiopia. This specifically dealt with factors controlling the losses, the fertility status of the deposited sediment, the nutrient export (NE) rates and associated costs. Enrichment ratio (ER) values >1 were observed for the plant nutrients and the finer soil fractions. The high ER is associated with the preferential transport of nutrients bound to finer soil fractions and the parent material dissolution and its transport via runoff. However, the fertility status of the deposited sediment is not sufficient by itself to support a sustainable crop growth and hence external addition is necessary, mainly for N and Pav fertilizer. Generally, rates of NE were high. The high OC export on the other hand dictates the potential of reservoir sediments for OC sequestration. The cost price of loss of only N and Pav, eroded from the catchment slopes, was estimated at ,34·2 million (Euros) in March 2006 for the Tigray. Pity enough, policy makers and beneficiaries do not realize the magnitude of the problem, which forms a major threat for the crop production in the country. Therefore, it is important not only to make the public aware of the problem but also of implementing integrated soil fertility management practices. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    Fallow cultivation system and farmers' resource management in Niger, West Africa

    LAND DEGRADATION AND DEVELOPMENT, Issue 3 2002
    A. Wezel
    Abstract A survey was carried out in 136 farm-households from seven villages in 1995 and 1996 to analyse the traditional fallow cultivation system in Niger. Farmers were asked to give information about land use on their fields, focusing on cropping and fallow periods as well as on cultivation changes compared to the past. In addition, they were interviewed about their management strategies to maintain or improve soil fertility. Millet-based systems clearly dominate at all sites, either in pure form or intercropped with cowpea, groundnut, sorghum or roselle. At present, almost half of all farmers cultivate their fields on average up to 5 years until it is left fallow. About one-third use their fields permanently. Most farmers use short fallow periods of 1 to 5 years. Moreover, there was a decrease in the cropping area left fallow, and the fallow period also decreased steadily in the past years. In the mid-1970s the average fallow period was about 8 years, decreasing to 2.5 years in 1996. The actual fallow periods are too short to allow sufficient positive effects on soil fertility and farmers are aware of this problem. Consequently, farmers employ different fertilization techniques which aim at maintaining or restoring the soil nutrient pool of the fields while providing physical protection against wind and water erosion. Most farmers use animal manure to improve soil fertility and apply mulch from different sources, millet stalks and branches, for soil regeneration. Few farmers employ other strategies such as mineral fertilizer or planting pits. The farmers try to optimize the use of internal and external resources resulting in a mixture of different fertilization and soil protection methods. Internal resources play by far the most important role. Due to the generally limited resource availability farmers concentrate their management efforts on certain areas within each field or on selected fields only. This means a decreased crop production for the individual household and a higher risk of soil degradation because of soil mining or increased erosion risk on the field area where soil fertility management cannot be practised. Copyright © 2002 John Wiley & Sons, Ltd. [source]