• Authors:
    • Raus, L.
    • Bucur, D.
    • Jitareanu, G.
    • Ailincai, C.
    • Ailincai, D.
    • Zbant, M.
  • Source: Cercetări Agronomice în Moldova
  • Volume: 42
  • Issue: 2
  • Year: 2009
  • Summary: The influence of long-term fertilization and irrigation on wheat and maize yield and soil fertility was studied at the Agricultural Research and Development Station of Podu-Iloaiei since 1980. These experiments were carried out on a 10% slope field, on a Cambic Chernozem with clayey loam texture (423 g clay, 315 g loam and 262 g sand), a neuter to weakly acid reaction and a mean nutrient supply. The mean annual rainfall amounts, recorded in the last 28 years, were higher, with values comprised between 12.7 and 279.2 mm, compared to the multiannual mean on 80 years (542 mm) in 16 years, and lower by 25.3-236.7 mm in 10 years. Annual application of rates of N 160 P 80, in a four-year crop rotation (soybean-wheat-sugar beet-maize)+a reserve field, cultivated with legumes and perennial grasses, determined the accumulation of a reserve of mobile phosphates of 78 mg/kg soil. Under irrigated, a good plant supply with mineral elements and the increase in the content of organic carbon from soil were done by applying the rate of N 80P 70+30 t/ha manure. Nitrogen and phosphorus fertilizers, although applied at high rates (N 130+100 P 2O 5), could not prevent the decrease in organic carbon content from soil.
  • Authors:
    • Steinbach, H. S.
    • Alvarez, R.
  • Source: Soil & Tillage Research
  • Volume: 104
  • Issue: 1
  • Year: 2009
  • Summary: The Argentine Pampas is one of the most important cropping regions of the World. Limited tillage systems, and specially no-till, had widespread in recent years, occupying actually around 70% of the surface devoted to annual crops. We review results produced in field experiments installed along the Pampas to determine the effect of the adoption of these tillage systems on some soil properties and crops yield. It was performed a meta-analysis of data from experiments where plow tillage (mouldboard plow), reduced tillage (chisel plow, disk plow or harrow disk) and no-till were compared. Treatments effects were contrasted by paired t-tests between groups of paired data. Soil bulk density and cone penetration resistance of the 0-20 cm layer were higher under limited tillage systems than under plow tillage. Increases of bulk density under no-till in comparison to plow tillage were generally small, averaging 4%, but cone penetration increased by 50% in many soils. The increase of bulk density was greater in soils of initial low bulk density. Neither bulk density increases nor cone penetration changes reached critical threshold for roots development. Aggregate stability and water infiltration rate were higher in soils subjected to limited tillage systems than under plow tillage. The improvement of aggregate stability was higher in poorer structured soils, with an average increase of 70% under no-till in relation to plow tillage. Under no-till infiltration rate doubled in average that of plow tillage. Soil water content during the critical periods of sowing and flowering was generally greater under limited tillage but, conversely, nitrate nitrogen levels were greater in plow tillage. Higher soil water content under no-till in relation to plow tillage may satisfied the evapotranspiration demand of 1-3 days of crops during the critical flowering period, being nitrate nitrogen in average 21 kg ha -1 lower under no-till. Soybean ( Glycine max (L.)-Merr.) yield was not affected by tillage system, meanwhile wheat ( Triticum aestivum L.) and corn ( Zea mays L.) yields were lower under reduced tillage and no-till than under plow tillage without nitrogen fertilization. Wheat and corn no-till yields were 10-14% lower that yields under plow tillage as a mean. When fertilizers were applied, wheat and corn yield differences between tillage treatments generally disappeared. The adoption of limited tillage systems in the Pampas leads to soil improvement but also generates the necessity of increase nitrogen fertilizers utilization to sustain yields of graminaceus crops.
  • Authors:
    • Anderson, R. L.
  • Source: Weed Technology
  • Volume: 23
  • Issue: 3
  • Year: 2009
  • Summary: This study measured weed interference in soybean and corn as affected by residue management tactics following a sequence of oat and winter wheat. Residue management tactics compared were conventional tillage, no-till, and no-till plus cover crops. Treatments were split into weed-free and weed-infested conditions; prominent weeds were green and yellow foxtail and common lambsquarters. Grain yield of soybean did not differ between weed-free and weed-infested conditions with no-till, whereas weeds reduced yield 25% in the tilled system. Corn responded inconsistently to treatments, with more than 40% yield loss due to weed interference in 1 yr with all treatments. Cover crops did not improve weed management compared with no-till in either crop. Seedling emergence of the weed community differed between tillage and no-till; density of weed seedlings was fivefold higher with tillage, whereas seedling emergence was delayed in no-till. The initial flush of seedlings occurred 2 to 3 wk later in no-till compared with the tilled system. Designing rotations to include cool-season crops in a no-till system may eliminate the need for herbicides in soybean to manage weeds.
  • Authors:
    • Vicente, M. C. de
    • Andersson, M. S.
  • Source: book
  • Year: 2009
  • Summary: This comprehensive volume provides the scientific basis for assessing the likelihood of gene flow between twenty important crops and their wild relatives. The crops discussed include both major staples and minor crops that are nonetheless critical to food security, including bananas and plantain, barley, canola, cassava, chickpeas, common beans, cotton, cowpeas, finger millet, maize, oat, peanuts or groundnuts, pearl millet, pigeonpeas, potatoes, rice, sorghum, soyabeans, sweet potatoes, and wheat. Each chapter is devoted to one of the crops and details crop-specific information as well as relevant factors for assessing the probability of gene flow. The crop-specific reviews provide insights into the possible ecological implications of gene escape. For each crop, a full-colour world map shows the modelled distributions of crops and wild relatives. These maps offer readers, at a glance, a means of evaluating areas of possible gene flow. The authors classify the areas of overlap into three "gene-flow categories" with respect to the possibility of genetic exchange. The systematic, unbiased findings provided here will promote well-informed decision making and the conservation of wild relatives of crops. This book is particularly relevant to agriculture in developing countries, where most crop biodiversity is found and where current knowledge on biodiversity conservation is limited. Given the ecological concerns associated with genetically modified crops, this reference is an essential tool for everyone working to feed a growing world population while preserving crop biodiversity.
  • Authors:
    • Domuta, C.
    • Ardelean, I.
    • Bandici, G.
  • Source: Analele Universităţii din Oradea, Fascicula: Protecţia Mediului
  • Volume: 14
  • Year: 2009
  • Summary: The paper sustain the importance of the crop rotation on quality of the wheat yield and is based on the results carried out during 2003-2006 in a long term trial out placed on the preluvosoil from Oradea in 1990. Both in nonirrigated and irrigated conditions the smallest values of the protein, wet gluten and dry gluten were obtained in wheat monocrop; the values increased in the crop rotation wheat maize and the biggest values were registered bin the crop rotation wheat-maize-soybean.
  • Authors:
    • Griffis, T. J.
    • Baker, J. M.
  • Source: Agricultural and Forest Meteorology
  • Volume: 149
  • Issue: 12
  • Year: 2009
  • Summary: Climate change and economic concerns have motivated intense interest in the development of renewable energy sources, including fuels derived from plant biomass. However, the specter of massive biofuel production has raised other worries, specifically that by displacing food production it will lead to higher food prices, increased incidence of famine, and acceleration of undesirable land use change. One proposed solution is to increase the annual net primary productivity of the existing agricultural land base, so that it can sustainably produce both food and biofuel feedstocks. This might be possible in corn and soybean production regions through the use of winter cover crops, but the biophysical feasibility of this has not been systematically explored. We developed a model for this purpose that simulates the potential biomass production and water use of winter rye in continuous corn and corn-soybean rotations. The input data requirements represent an attempt to balance the demands of a physically and physiologically defensible simulation with the need for broad applicability in space and time. The necessary meteorological data are obtainable from standard agricultural weather stations, and the required management data are simply planting dates and harvest dates for corn and soybeans. Physiological parameters for rye were taken from the literature, supplemented by experimental data specifically collected for this project. The model was run for a number of growing seasons for 8 locations across the Midwestern USA. Results indicate potential rye biomass production of 1-8 Mg ha(-1), with the lowest yields at the more northern sites, where both PAR and degree-days are limited in the interval between fall corn harvest and spring corn or soybean planting. At all sites rye yields are substantially greater when the following crop is soybean rather than corn, since soybean is planted later. Not surprisingly, soil moisture depletion is most likely in years and sites where rye biomass production is greatest. Consistent production of both food and biomass from corn/winter rye/soybean systems will probably require irrigation in many areas and additional N fertilizer, creating possible environmental concerns. Rye growth limitations in the northern portion of the corn belt may be partially mitigated with aerial seeding of rye into standing corn. Published by Elsevier B.V.
  • Authors:
    • Smith, H. J.
    • Trytsman, G.
    • Bloem, J. F.
  • Source: Biological Nitrogen Fixation: Towards Poverty Alleviation through Sustainable Agriculture
  • Volume: 48
  • Issue: 1-3
  • Year: 2009
  • Summary: Farm lands of resource-poor communities in South Africa are depleted of nutrients due to continuous mono-cropping, limited use of fertilisers, and sometimes leaching caused by high rainfall. Despite the well-known advantages of biological nitrogen fixation (BNF) in cropping systems, less than 10% of the grain crops planted annually in these areas are legumes. Using a participatory research and development approach, resource-poor farmers were introduced to conservation agriculture (CA) practices, including BNF, that promoted zero (or reduced) tillage, increased retention of soil cover, as well as crop diversification. Because crop rotation and intercropping of legumes with cereals are known to contribute to soil fertility while enhancing food security, resource-poor fanners from various Provinces in South Africa were trained on the benefits of legume culture for eight years. As a result, these resource-poor farmers did not only get training in inoculation techniques, but were also supplied with inoculants for use on their farms. Data collected from Farmers Demonstration Trials at Belvedere, Dumbarton and Lusikisiki, showed that the grain and fodder yield of maize planted after legumes, and maize intercropped with legumes, were comparable to those of maize receiving high N fertilizer dose (i.e. 54 kg N at planting and 54 kg N as top-dressing). The same data further showed that Rhizobium inoculation, when combined with application of low levels of P and K. significantly increased crop yields within farmers' trial plots. BNF therefore offers a great opportunity for resource-poor farmers in South Africa to increase their crop yields and thus improve the quality of their livelihoods through the adoption of affordable and sustainable biological technologies that enhance soil fertility.
  • Authors:
    • Bolotova, N. S.
  • Source: Kormoproizvodstvo
  • Issue: 12
  • Year: 2009
  • Summary: Techniques and standards for production of haylage and silage from high-protein fodder mixtures of pea, oat, rape, vetch, barley, beans, rye, wheat and maize are discussed. Plants should be cut into 15-20 mm pieces when the protein content of fodder mixture is over 30%, and into 40-50 mm pieces when the protein content of fodder mixture is less than 20%. Bales of silage mass are wrapped in film and roll size is 1.2 m wide and 0.8-1.6 m in diameter. The high yield of maize, vetch, and oat-rape mixture achievable in the conditions of European Russia is 10.8 t/ha of dry mass and 1.2 t/ha of protein.
  • Authors:
    • Jain, L.
    • Kothari, A.
    • Sharma, S.
    • Balyan, J.
    • Jat, M.
  • Source: Journal of Maharashtra Agricultural Universities
  • Volume: 33
  • Issue: 3
  • Year: 2008
  • Summary: A field experiment was conducted during the kharif season of 2001-2004 at Dryland Farming Research Station, Arjia, Bhilwara, Rajasthan, India, to study the suitability of different cropping system of maize and land treatments for reducing runoff and soil loss. Among the land treatments, flat sowing and ridging after first inter-cultural operation in maize was found more effective in reducing runoff and soil loss thereby increasing the yield of maize. Whereas, among cropping systems, intercropping of maize+black gram (2:2) was found more effective in reducing runoff and soil loss and thereby increasing crop yields as compared to sole maize and black gram.
  • Authors:
    • Currie, R. S.
    • Klocke, N. L.
    • Stone, L. R.
  • Source: Proceedings of the World Environmental and Water Resources Congress 2008: Ahupua'A
  • Year: 2008
  • Summary: A field study was conducted near Garden City, Kansas to measure corn grain yield response to a range of rates from full to deficit irrigation. The contributions of antecedent stored soil water to crop water use were determined from soil water measurements near the beginning and the end of the growing season. Above average winter precipitation contributed to pre-plant soil water accumulations and deficit irrigation caused more growing season stored soil water use. Field results were compared with the Crop Water Yield (CWY) predictions of field results. Correlation of relative yields from field results and the CWY simulation were good, showing that the CWY has potential to be used as a management tool to screen potential irrigation scheduling scenarios for deficit irrigation.