• Authors:
    • Berzy, T.
    • Hegyi, Z.
  • Source: Cereal Research Communications
  • Volume: 37
  • Issue: Suppl. 1
  • Year: 2009
  • Summary: If maize production is to be successful it is essential to be clear about the intended end-use and the farm conditions in order to make a wise choice of variety and technology. Recommendations on the end-use of the varieties can only be made based on knowledge of both yield levels and chemical quality. A total of 96 hybrids from four FAO maturity groups were examined at four locations in 2008 in order to analyse their yield and quality and to determine the effect of ecological factors on a number of parameters. The highest yield averages were recorded for hybrids in the FAO 300 group (12.95 t ha -1) at locations with the highest rainfall (Debrecen). In Debrecen and Iregszemcse the plants were able to develop a second ear, thus increasing the yield average (12.31 t ha -1, 11.75 t ha -1). In Szarvas irrigation helped to achieve good yields and reduce drought damage (10.97 t ha -1), while in Martonvasar, although rainfall sums were adequate, the uneven distribution and atmospheric drought led to lower yields (9.65 t ha -1). In this experiment, early hybrids (FAO, 200, FAO 300) had the best yield stability. The starch content of the grain exhibited a close correlation with the yield average. The greatest starch incorporation was recorded for FAO 300 hybrids (72.86%). The expected negative correlation between starch content and protein/oil content was observed. The FAO 200 hybrids had the highest protein and oil contents (9.70 and 3.89%), which gradually declined at later maturity dates (FAO 500: 9.14 and 3.51%). The thousand-kernel mass and the length of the main ear were closely correlated with the maturity date, being lowest for the earliest hybrids (326.39 g, 18.91 cm) and highest in the latest group (346.91 g, 19.74 cm). For protein and oil content, genetic differences between the hybrids were greater (1.50, 1.00%) than between locations (0.97, 0.82%), while in the case of starch the latter caused greater differences (2.84, 4.06%).
  • Authors:
    • Blignaut, J.
    • Ueckermann, L.
    • Aronson, J.
  • Source: South African Journal of Science
  • Volume: 105
  • Issue: 1/2
  • Year: 2009
  • Summary: South Africa in general has been approximately 2% hotter and at least 6% drier over the ten years between 1997 and 2006 compared to the 1970s. The use of water has also increased greatly over this same period. By 2000, 98.6% of that year's surface water yield and 41% of the annual utilisable potential of groundwater was allocated to use. Irrigation agriculture, comprising 60% of total consumption, is by far the largest single consumer of water. Given these climatic and water use changes as a backdrop, we employed a panel data econometric model to estimate how sensitive the nation's agriculture may be to changes in rainfall. Net agricultural income in the provinces, contributing 10% or more to total production of both field crops and horticulture, is likely to be negatively affected by a decline in rainfall, especially rain-fed agriculture. For the country as a whole, each 1% decline in rainfall is likely to lead to a 1.1% decline in the production of maize (a summer grain) and a 0.5% decline in winter wheat. These results are discussed with respect to both established and emerging farmers, and the type of agriculture that should be favoured or phased out in different parts of the country, in view of current and projected trends in climate, increasing water use, and declining water availability.
  • Authors:
    • Djurovic, D.
    • Dugalic, G.
    • Stevovic, V.
    • Paunovic, A.
    • Bokan, N.
  • Source: Agroznanje - Agro-knowledge Journal
  • Volume: 10
  • Issue: 3
  • Year: 2009
  • Summary: Average grain yields of maize, undoubtedly the most common field crop grown in the Balkans, are still significantly lower than its genetic and practical potential. All known cultural practices have not yet been applied sufficiently. Hence the constant need to conduct trials to confirm the necessity to employ known technological practices in the cultivation of old and novel maize hybrids. The generally low average yields of maize grown under dryland conditions can be increased by available cultural practices including the selection of drought-tolerant hybrids, adequate crop rotation, the use of the most suitable tillage system and basic fertilization, optimal plant density, interrow cultivation and fertilization. The trial was set up as a randomized block design on leached alluvial soil. The following hybrids were studied: NS 50402, NS 540, ZP 570, ZP 580 and ZP 599, being fertilized under three treatments: basic treatment (30 t/ha manure and 400 t/ha of composite 15:15:15 fertilizer prior to sowing), N1 (250 kg/ha CAN) and N2 (500 kg/ha CAN). The average yield of dry maize grain was 9.65 t/ha. Averagely for the hybrids, the low and high nitrogen application rates induced 0.32 t/ha and 0.55 t/ha yield increases, respectively. The plot fertilized every second year with manure and composite mineral fertilizer gave a satisfactory yield of 9.36 t/ha. The highest average yield of 10.61 t/ha under all treatments was produced by ZP580 hybrid. The above-average yield, achieved under non-irrigated conditions, was largely induced by combined organic and mineral fertilization, since the plants were able to better tolerate the drought conditions due to a sufficient amount of readily available nutrients.
  • Authors:
    • Brown, S.
    • Westhoff, P.
  • Issue: 05-09
  • Year: 2009
  • Summary: This report incorporates higher energy prices estimated by CRA International under H.R. 2454 (The American Clean Energy and Security Act of 2009) on Missouri crop production costs. This analysis uses current 2009 Missouri crop production cost estimates as the base and examines the level of these production costs in 2020, 2030, 2040 and 2050 assuming these production costs change only as a result of the higher energy costs estimated by CRA International under H.R. 2454. Using the 11, 34 and 45 percent increases found by CRA International in motor fuel, natural gas and electricity prices, respectively, by 2050 as a result of H.R. 2454, estimated Missouri crop operating costs increase by 8.1, 8.8, 4.4 and 10.4 percent for dryland maize, irrigated maize, soyabeans and wheat, respectively.
  • Authors:
    • Hunt, J. R.
    • Dalgliesh, N. P.
    • McCown, R. L.
    • Whish, J. P. M.
    • Robertson, M. J.
    • Foale, M. A.
    • Poulton, P. L.
    • Rees, H. van
    • Carberry, P. S.
    • Hochman, Z.
  • Source: Crop & Pasture Science
  • Volume: 60
  • Issue: 11
  • Year: 2009
  • Summary: Crop simulation models relevant to real-world agriculture have been a rationale for model development over many years. However, as crop models are generally developed and tested against experimental data and with large systematic gaps often reported between experimental and farmer yields, the relevance of simulated yields to the commercial yields of field crops may be questioned. This is the third paper in a series which describes a substantial effort to deliver model-based decision support to Australian farmers. First, the performance of the cropping systems simulator, APSIM, in simulating commercial crop yields is reported across a range of field crops and agricultural regions. Second, how APSIM is used in gaining farmer credibility for their planning and decision making is described using actual case studies. Information was collated on APSIM performance in simulating the yields of over 700 commercial crops of barley, canola, chickpea, cotton, maize, mungbean, sorghum, sugarcane, and wheat monitored over the period 1992 to 2007 in all cropping regions of Australia. This evidence indicated that APSIM can predict the performance of commercial crops at a level close to that reported for its performance against experimental yields. Importantly, an essential requirement for simulating commercial yields across the Australian dryland cropping regions is to accurately describe the resources available to the crop being simulated, particularly soil water and nitrogen. Five case studies of using APSIM with farmers are described in order to demonstrate how model credibility was gained in the context of each circumstance. The proposed process for creating mutual understanding and credibility involved dealing with immediate questions of the involved farmers, contextualising the simulations to the specific situation in question, providing simulation outputs in an iterative process, and together reviewing the ensuing seasonal results against provided simulations. This paper is distinct from many other reports testing the performance and utility of cropping systems models. Here, the measured yields are from commercial crops not experimental plots and the described applications were from real-life situations identified by farmers. A key conclusion, from 17 years of effort, is the proven ability of APSIM to simulate yields from commercial crops provided soil properties are well characterised. Thus, the ambition of models being relevant to real-world agriculture is indeed attainable, at least in situations where biotic stresses are manageable.
  • Authors:
    • NASS
    • USDA
  • Year: 2009
  • Authors:
    • Bauer, P. J.
    • Watts, D. W.
    • Frederick, J. R.
    • Novak, J. M.
  • Source: Soil Science Society of America Journal
  • Volume: 73
  • Issue: 2
  • Year: 2009
  • Summary: Long-term disk tillage (DT) for cotton (Gossypium hirsutum L.) production in the southeastern U.S. Coastal Plain has resulted in soil organic C (SOC) content reductions. Conservation tillage (CT) management in some studies can rebuild SOC levels. A field study, with two adjacent 3.5-ha fields, both containing soil series formed in upland and depressional areas, was conducted using a 6-yr rotation of corn (Zea mays L.) and cotton to determine the CT and DT effects on SOC contents and residue characteristics returned to the soil. Annual soil samples were collected from 50 locations per field at 0- to 3- and 3- to 15-cm. After 6 yr under CT, residue accumulation promoted a significant SOC increase in the 0- to 3-cm depth in the upland soil series (about 0.7 Mg SOC ha(-1)). The lack of residue mixing in the 3- to 15-cm depth in upland Soils under CT however, resulted in a significant SOC content decline at this depth (1.25-2.51 Mg SOC ha(-1)). There was no significant SOC content change in soils under CT formed in depressional areas or in all soils under DT During 6 yr, 14.8 Mg ha(-1) of organic C from both corn and cotton residues was returned to Soils under CT but <4% was incorporated into the SOC pool. Levels of SOC in sandy upland soils can be increased at the surface after 6 yr of CT under a corn and cotton rotation, with the increase coming at the expense of an SOC decline at a deeper topsoil depth.
  • Authors:
    • Jackson, R. B.
    • Murray, B. C.
    • Baker, J.
    • Jobbagy, E. G.
    • Pineiro, G.
  • Source: Ecological Applications
  • Volume: 19
  • Issue: 2
  • Year: 2009
  • Summary: Although various studies have shown that corn ethanol reduces greenhouse gas (GHG) emissions by displacing fossil fuel use, many of these studies fail to include how land-use history affects the net carbon balance through changes in soil carbon content. We evaluated the effectiveness and economic value of corn and cellulosic ethanol production for reducing net GHG emissions when produced on lands with different land-use histories, comparing these strategies with reductions achieved by set-aside programs such as the Conservation Reserve Program (CRP). Depending on prior land use, our analysis shows that C releases from the soil after planting corn for ethanol may in some cases completely offset C gains attributed to biofuel generation for at least 50 years. More surprisingly, based on our comprehensive analysis of 142 soil studies, soil C sequestered by setting aside former agricultural land was greater than the C credits generated by planting corn for ethanol on the same land for 40 years and had equal or greater economic net present value. Once commercially available, cellulosic ethanol produced in set-aside grasslands should provide the most efficient tool for GHG reduction of any scenario we examined. Our results suggest that conversion of CRP lands or other set-aside programs to corn ethanol production should not be encouraged through greenhouse gas policies.
  • Authors:
    • Fortin, J.
    • Tremblay, G.
    • Ziadi, N.
    • Chantigny, M. H.
    • Rochette, P.
    • Angers, D. A.
    • Poirier, V.
  • Source: Soil Science Society of America Journal
  • Volume: 73
  • Issue: 1
  • Year: 2009
  • Summary: Both tillage and fertilizer management influence soil organic C (SOC) storage, but their interactive effects remain to be determined for various soil and climatic conditions. We evaluated the long-term effects of tillage (no-till, NT, and moldboard plowing, MP), and N and P fertilization on SOC stocks and concentrations in profiles of a clay loam soil (clayey, mixed, mesic Typic Humaquept). Corn (Zea mays L.) and soybean [Glycine max (L) Merr.] were grown in a yearly rotation for 14 yr. Our results showed that NT enhanced the SOC content in the soil surface layer, but MP resulted in greater SOC content near the bottom of the plow layer. When the entire soil profile (0-60 cm) was considered, both effects compensated each other, which resulted in statistically equivalent SOC stocks for both tillage practices. Nitrogen and P fertilization with MP increased the estimated crop C inputs to the soil but did not significantly influence SOC stocks in the whole soil profile. At the 0- to 20-cm depth, however, lower C stocks were measured in the plowed soil with the highest N fertilizer level than in any other treatment, which was probably caused by a greater decomposition of crop residues and soil organic matter. Conversely, the highest SOC stocks of the 0- to 20-cm soil layer were observed in the NT treatment with the highest N rates, reflecting a greater residue accumulation at the soil Surface. When accounting for the whole soil profile, the variations in surface SOC due to tillage and fertilizer interactions were masked by tillage-induced differences in the 20- to 30-cm soil layer.
  • Authors:
    • Grau, R.
    • Baptista, S.
    • Birkenholtz, T.
    • Lambin, E. F.
    • Ickowitz, A.
    • Hecht, S.
    • Geoghegan, J.
    • Lawrence, D.
    • DeFries, R. S.
    • Turner, B. L.
    • Uriarte ,M.
    • Schneider ,L.
    • Rudel, T. K.
  • Source: Proceedings of the National Academy of Sciences of the United States of America
  • Volume: 106
  • Issue: 49
  • Year: 2009
  • Summary: Does the intensification of agriculture reduce cultivated areas and, in so doing, spare some lands by concentrating production on other lands? Such sparing is important for many reasons, among them the enhanced abilities of released lands to sequester carbon and provide other environmental services. Difficulties measuring the extent of spared land make it impossible to investigate fully the hypothesized causal chain from agricultural intensification to declines in cultivated areas and then to increases in spared land. We analyze the historical circumstances in which rising yields have been accompanied by declines in cultivated areas, thereby leading to land-sparing. We use national-level United Nations Food and Agricultural Organization data on trends in cropland from 1970-2005, with particular emphasis on the 1990-2005 period, for 10 major crop types. Cropland has increased more slowly than population during this period, but paired increases in yields and declines in cropland occurred infrequently, both globally and nationally. Agricultural intensification was not generally accompanied by decline or stasis in cropland area at a national scale during this time period, except in countries with grain imports and conservation set-aside programs. Future projections of cropland abandonment and ensuing environmental services cannot be assumed without explicit policy intervention.