• Authors:
    • Bengtson, L. E.
    • Fagre, D.
    • Pederson, G.
    • Zeyuan, Q.
    • Prato, T.
    • Williams, J. R.
  • Source: Environmental Management
  • Volume: 45
  • Issue: 3
  • Year: 2010
  • Summary: Potential economic impacts of future climate change on crop enterprise net returns and annual net farm income (NFI) are evaluated for small and large representative farms in Flathead Valley in Northwest Montana. Crop enterprise net returns and NFI in an historical climate period (1960-2005) and future climate period (2006-2050) are compared when agricultural production systems (APSs) are adapted to future climate change. Climate conditions in the future climate period are based on the A1B, B1, and A2 CO(2) emission scenarios from the Intergovernmental Panel on Climate Change Fourth Assessment Report. Steps in the evaluation include: (1) specifying crop enterprises and APSs (i.e., combinations of crop enterprises) in consultation with locals producers; (2) simulating crop yields for two soils, crop prices, crop enterprises costs, and NFIs for APSs; (3) determining the dominant APS in the historical and future climate periods in terms of NFI; and (4) determining whether NFI for the dominant APS in the historical climate period is superior to NFI for the dominant APS in the future climate period. Crop yields are simulated using the Environmental/Policy Integrated Climate (EPIC) model and dominance comparisons for NFI are based on the stochastic efficiency with respect to a function (SERF) criterion. Probability distributions that best fit the EPIC-simulated crop yields are used to simulate 100 values for crop yields for the two soils in the historical and future climate periods. Best-fitting probability distributions for historical inflation-adjusted crop prices and specified triangular probability distributions for crop enterprise costs are used to simulate 100 values for crop prices and crop enterprise costs. Averaged over all crop enterprises, farm sizes, and soil types, simulated net return per ha averaged over all crop enterprises decreased 24% and simulated mean NFI for APSs decreased 57% between the historical and future climate periods. Although adapting APSs to future climate change is advantageous (i.e., NFI with adaptation is superior to NFI without adaptation based on SERF), in six of the nine cases in which adaptation is advantageous, NFI with adaptation in the future climate period is inferior to NFI in the historical climate period. Therefore, adaptation of APSs to future climate change in Flathead Valley is insufficient to offset the adverse impacts on NFI of such change.
  • Authors:
    • Skuodiene, R.
    • Repsiene, R.
  • Source: Žemdirbystė (Agriculture)
  • Volume: 97
  • Issue: 4
  • Year: 2010
  • Summary: The current paper presents the results of experiments carried out at the Lithuanian Institute of Agriculture's Vezaiciai Branch during the period 2005-2009 on a Dystric Albeluvisol (ABd). We explored the effects of farmyard manure, alternative organic and lime fertilisers on soil agrochemical indicators and their relationship with weed incidence in a crop rotation (winter wheat -> lupine-oats mixture -> winter oilseed rape -> spring barley undersown with perennial grasses). Unlimed and farmyard manure - unfertilised soil was very acid, with a pH(KCl) of 4.0-4.3, hydrolytic acidity of 56.32-68.11 mequiv kg(-1) and mobile Al of 77.8-143.7 mg kg(-1). In unlimed soil applied with 40 and 60 t ha(-1) rates of farmyard manure hydrolytic acidity declined to 56.78-40.52 mequiv kg(-1), the content of mobile Al dramatically declined to 39.3-8.5 mg kg(-1), pH(KCl) increased to 4.3-4.6. Unlimed and farmyard manure-unfertilised soil contained 678-777.3 mg kg(-1) of exchangeable Ca and 157.7-163.3 mg kg(-1) of exchangeable Mg. In the soil fertilised with farmyard manure the content of exchangeable Ca increased by 1.4-2.8 times and that of exchangeable Mg by 1.0-1.5 times. In limed soil, the acidity was most markedly reduced by lime fertilisers, only traces (1.0-0.9 mg kg(-1)) of mobile Al were identified, a significant reduction in hydrolytic acidity occurred and pH(KCl) increased. Through the application of all organic fertilisers hydrolytic acidity declined by 17-18%, pH(KCl) value increased by 6-7%, compared with the limed soil. The highest increase (1.3-1.5 times) in exchangeable Ca content resulted from lime fertilisers, while exchangeable Mg content increased by up to 1.5 times. In limed and organically fertilised soil the highest contents of exchangeable Ca and Mg (2917.3-1949.0 mg kg(-1) and 322.7-243.0 mg kg(-1)) were recorded in the treatments applied with 60 t ha(-1) of farmyard manure. Alternative organic fertilisers were not more effective than farmyard manure in reducing soil acidity. The effects of the agricultural practices applied on the crop weed incidence manifested themselves in all experimental years. In the first year of organic fertiliser effect (in the winter wheat crop), strong correlations were established between soil agrochemical indicators and weed number and mass. In the second year of effect, due to the adverse weather conditions and poorer weed suppression capacity of lupine, the relationship between the number of weeds, their mass and individual agrochemical indicators was insignificant, except for that between weed mass and mobile Al content. Strong correlations were established in the third and fourth years of effect for winter oilseed rape and barley crops, respectively.
  • Authors:
    • Bathgate, A.
    • Lawes, R. A.
    • Robertson, M. J.
    • Byrne, F.
    • White, P.
    • Sands, R.
  • Source: Crop and Pasture Science
  • Volume: 61
  • Issue: 3
  • Year: 2010
  • Summary: Break crops (e. g. pulses, lupins, canola, oats) underpin the continued profitability of cereal (wheat or barley) based cropping sequences. The area sown on farms to break crops varies widely across geographical regions according to climate, soil type mix, enterprise mix (crop v. livestock), and other constraints such as the prevalence of soil-borne disease. Given recent fluctuations in the area of established break crops in Western Australia, there are concerns about their long-term prospects in the farming system. A survey of the area and grain yield of break crops on-farm was combined with whole-farm bio-economic modelling to determine the upper limit to the area of break crops on representative farms in 4 agro-climatic regions. Sensitivity analysis was conducted to ascertain the potential effects of varying commodity prices (sheep and grain), costs of production, and assumptions on the yield of break crops and the boost to the yield of following cereals. The survey revealed that the two dominant break crops, lupins and canola, occupied 8-12% and 8-9%, respectively, of farm area on those farms that grew them in the medium-rainfall zone and this declined to 6-8% and 7-10% in the drier region. Nevertheless, the modelling results show that break crops are an important component of the farming system, even where the area is small, and the response of whole-farm profit to percent of the farm allocated to break crops is relatively. at near the optimum of 23-38%. The modelled area of break crops at maximum profit is higher than that found in farm surveys. The discrepancy could possibly be explained by the lower break crop yields realised by farmers and a reduced boost to cereal yields following break crops than assumed in models. Also, deterministic models do not account for risk, which is an important consideration in the decision to grow break crops. However, the yield difference does not explain the discrepancy entirely and raises questions about farmer motivations for adoption of break crops. The scope for increased area of break crops beyond 23-38% of the farm is limited, even with increases in the yield enhancements in subsequent cereal crops, higher break crop prices, and higher fertiliser costs. Further research is required to better quantify costs and benefits of break crops in Western Australian farming systems.
  • Authors:
    • Munier-Jolain, N. M.
    • Kurstjens, D. A. G.
    • Colbach, N.
    • Dalbies, A.
    • Dore, T.
  • Source: European Journal of Agronomy
  • Volume: 32
  • Issue: 3
  • Year: 2010
  • Summary: Because of environmental and health safety issues. it is necessary to develop strategies that do not rely on herbicides to manage weeds. Introducing temporary grassland into annual crop rotations and mechanical weeding are the two main features that are frequently used in integrated and organic cropping systems for this purpose. To evaluate the contribution of these two factors in interaction with other cropping system components and environmental conditions, the present study updated an existing biophysical model (i.e. ALOMYSYS) that quantifies the effects of cropping system oil weed dynamics. Based oil previous experiments, new sub-models were built to describe the effects on plant survival and growth reduction of mechanical weeding resulting from weed seedling uprooting and covering by soil, and those of grassland mowing resulting from tiller destruction. Additional modifications described the effect of the multiyear crop canopy of grassland on weed survival, growth, development and seed return to the soil. The improved model was used to evaluate the weed dynamics over 27 years in the conventional herbicide-based cropping system most frequently observed in farm Surveys (i.e. oilseed rape/winter wheat/winter barley rotation with Superficial tillage) and then to test prospective non-chemical scenarios. Preliminary simulations tested a large range of mechanical weeding and mowing strategies, varying operation frequencies, dates and, in the case of mechanical weeding, characteristics (i.e. tool, working depth, tractor speed). For mechanical weeding soon after sowing, harrowing was better than hoeing for controlling weed seed production. The later the operation, the more efficient the hoeing and the less efficient the harrowing. Tractor speed had little influence. Increasing tilling depth increased plant mortality but increased weed seed production because of additional seed germination triggering by the weeding tool. Decreasing the interrow width for hoeing was nefarious for weed control. The best combinations were triple hoeing in oilseed tape and sextuple harrowing in cereals. The best mowing strategy was mowing thrice, every 4-6 weeks, starting in mid-May. The best individual options were combined, simulated over 27 years and compared to the herbicide-based reference system. If herbicide applications were replaced solely by mechanical weeding, blackgrass infestation Could not be satisfactorily controlled. If a three-year lucerne was introduced into the rotation, weed infestations were divided by ten. Replacing chisel by mouldboard ploughing before winter wheat reduced weed infestations at short, medium and long term to a level comparable to the herbicide-based reference system. (C) 2009 Elsevier B.V. All rights reserved.
  • Authors:
    • Shimi, P.
    • Fereidoonpoor, M.
    • Jamali, M.
  • Source: Proceedings of 3rd Iranian Weed Science Congress, Volume 2: Key papers, weed management and herbicides, Babolsar, Iran, 17-18 February 2010
  • Year: 2010
  • Summary: In order to compare efficacy of Pantera (quizalofop-P-tefuryl 4%EC) with other graminicides in canola fields of Fars province, an experiment was carried out in randomized complete block design with 4 replication and 11 treatments in Darab research station in 2008-2009. Treatments included Pantera at 1, 1.5 and 2 lha -1, Galant super (haloxyfop-R-methyl aster) at 0.75 lha -1, Focus (cycloxydim) at 2 lha -1, Treflan, (trifluralin 48% EC) at 2 lha -1, Butisan star (metazachlor 33.33%+quinmerac 8.8%) at 2.5 lha -1, Treflan at 2 lha -1+Pantera at 1.5 lha -1, Treflan at 2 lha -1+Galant super at 0.75 lha -1, Treflan at 2 lha -1+Focus 2 lha -1 and full season weed control as check. Results showed that 2 lha -1 Pantera in compare with Treflan+other graminicides as super gallant, focus and Pantera and full season weed control treatment had no significant difference and increased canola yield by 39.5-41.7%. Also, 2 lha -1 Pantera controlled wheat, barley, wild oat and ryegrass. In 100, 100, 90.97 and 92.92 percent respectively and 75.4 percent in decreasing of dry weight of grasses.
  • Authors:
    • Gaweda, D.
  • Source: Annales Universitatis Mariae Curie-Sklodowska. Sectio E, Agricultura
  • Volume: 65
  • Issue: 4
  • Year: 2010
  • Summary: The present research aimed at evaluating the de-weeding influence of the stubble crops including species composition, number and weight of air-dried weed in spring oats grown in monoculture. The experiment was set in four replications by means of the split-blok method on the stand after spring barley. The type of stubble crops (white mustard, fiddleneck, winter rapeseed, and a mixture of legumes: narrow-leafed lupine+field pea) annually ploughed after the oats harvest was the experimental factor. Only mechanical nursery operations were applied during the experiment; it consisted in harrowing made at 3-4 leaves stage. The highest number of weeds per 1 square meter area was recorded in oats cultivated after a mixture of legumes (narrow-leafed lupine+field pea). As compared to the mixture of legumes, the number of weeds per 1 m 2 was significantly lower after a winter rapeseed, fiddleneck and on the control object. For three experimental years, ploughed stubble crops did not significantly modify the weight of air-dried weed in oats canopy. Chenopodium album was the dominating weed on all experimental plots. The lowest number of this species was observed on the control object, while the highest in oats sown after white mustard.
  • Authors:
    • Gaweda, D.
    • Harasim, E.
  • Source: Annales Umcs, Agricultura
  • Volume: 65
  • Issue: 1
  • Year: 2010
  • Summary: The objective of the study was to assess the effect of catch crops on the yield and energetic efficiency of the main cereal crop grown under monoculture. The study was carried out in the years 2006-2008 at Uhrusk experiment farm. The trial was localized on a mixed rendzina soil, of medium depth, developed from chalk limestone. The experiment included spring cereals such as wheat, barley and oats as well as stubble catch crops: non-catch crop control, white mustard, blue phacelia, winter oilseed rape and a legume mixture - narrow-leaved lupin+field peas. The highest yield increase over the non-catch crop control (9.4%) was found when phacelia was grown as a catch crop after wheat. The lowest yield increment occurred in barley grown after legumes (ca. 8%) and in oats gown after phacelia and oilseed rape (ca. 7%). The energetic efficiency of cereal production was more related to the main cereal crop than to the catch crop. The production of barley and oats had a higher energetic efficiency (4.71 and 4.65, respectively) than that of wheat (3.84). The use of catch crops lowered but to a small degree the energetic efficiency of spring cereal production.
  • Authors:
    • Tabil, L. G.
    • Adapa, P. K.
    • Schoenau, G. J.
  • Source: Applied Engineering in Agriculture
  • Volume: 26
  • Issue: 4
  • Year: 2010
  • Summary: Compaction of low bulk density agricultural biomass is a critical and desirable operation for sustainable and economic availability of feedstock for biofuel industry. A comprehensive study of the compression characteristics (density of pellet and total specific energy required for compression) of ground non-treated and steam-exploded barley, canola, oat, and wheat straw obtained from three hammer mill screen sizes of 6.4, 3.2 and 1.6 mm at 10% moisture content (wb) was conducted. Four preset pressures of 31.6, 63.2, 94.7, and 138.9 MPa were applied using an Instron testing machine to compress samples in a cylindrical die. Ground steam-exploded barley straw at screen sizes of either 3.2 or 1.6 mm produced high density compacts, while ground steam-exploded canola, oat, and wheat straw at screen sizes of 6.4, 3.2 or 1.6 mm produced high density compacts. Steam-exploded barley straw for 3.2 mm at 138.9 MPa produced compacts having 13% higher density and consumed 19% lower total specific energy compared to non-treated straw. Steam-exploded canola straw for 1.6 mm at 138.9 MPa produced compacts having 13% higher density and consumed 22% higher total specific energy compared to non-treated straw. Steam-exploded oat straw for 3.2 mm at 94.7 MPa produced compacts having 19% higher density and consumed 13% higher total specific energy compared to non-treated straw. Steam-exploded wheat straw for 6.4 mm at 138.9 MPa produced compacts having 17% higher density and consumed 17% higher total specific energy compared to non-treated straw. Three compression models, namely: Jones model, Cooper-Eaton model, and Kawakita-Ludde model were considered to determine the pressure-volume and pressure-density relationship of non-treated and steam-exploded straws. Kawakita-Ludde model provided the best fit to the experimental data having R 2 values of 0.99 for non-treated straw and 1.00 for steam-exploded biomass samples. The steam-exploded straw had higher porosity than non-treated straw. In addition, the steam-exploded straw was easier to compress since it had lower yield strength or failure stress values compared to non-treated straw.
  • Authors:
    • Hoffmann, A. A.
    • Umina, P. A.
    • Weeks, A. R.
    • Arthur, A. L.
  • Source: Experimental and Applied Acarology
  • Volume: 52
  • Issue: 2
  • Year: 2010
  • Summary: Balaustium medicagoense and Bryobia spp. have recently been identified as emerging pests of winter crops and pastures in Australia. These mites have a high natural tolerance to currently registered pesticides, highlighting the need to develop alternative control strategies such as cultural controls which require an understanding of plant associations. In shade-house experiments, Bryobia spp. survived and reproduced successfully on pasture, lupins and oats, but progeny failed to reach the adult stage on canola and wheat. Balaustium medicagoense progeny failed to produce a generation on any crop but parental adults survived a few months on all crops, particularly wheat. Bryobia spp. damaged canola, pasture and lupins, but caused minimal damage to oats and wheat, whereas Ba. medicagoense caused considerable damage to wheat and lupins, but only moderate damage to canola, oats and pasture. Field survey data, taken from approximately 450 sites across southern Australia, combined with analysis of historical pest reports, suggest broadleaf crops such as canola, lucerne, lupins and weeds appear particularly susceptible to attack by Bryobia species. Balaustium medicagoense was more commonly found on cereals and grasses, although they also attacked broadleaf crops, particularly canola, lucerne and lupins. These findings show that the mites have the potential to be an important pest on several winter grain crops and pasture, but there are important differences that can assist in management strategies such as targeted crop rotations.
  • Authors:
    • Bartosik, R.
  • Source: Julius-Kühn-Archiv
  • Issue: 425
  • Year: 2010
  • Summary: Concerning grain production, South America is divided in two main regions: (1) the Mercosur region (Argentina, Brazil, Uruguay and Paraguay) which produces more than 250 million tonnes of grains and oilseeds, and (2) the Andes Mountain region countries, which are net importers of these products. The main challenges related to grain postharvest that South America is facing are to minimize the quality and quantity losses; improve the food safety; enhance the capability for segregation and traceability of identity preserved (IP) grains; and incorporate technology to maintain the overall efficiency of the postharvest system. Among the critical points affecting the efficiency of the system are the shortage of permanent storage capacity; large storage structures which affects the segregation of IP grains; deficient transportation system (roads and railroads); poor management of integrated pest control system; and unsatisfied demand of formal and informal education in suitable grain postharvest technologies and practices. However, the region remains highly competitive in producing and delivering food for the rest of the world and it has demonstrated high capacity for incorporating cost efficient grain handling technologies. As a result, one of the main changes in the region was the appearance of the silobag system for temporary storage of dry grain and oilseeds. Each silobag can hold approximately 200 tonnes of wheat and with the available handling equipment is quite simple to load and unload. During the 2008 harvest season, more than 33 million tonnes of grain were stored in these plastic bags in Argentina (including corn, soybean, wheat, sunflower, malting barley, canola, cotton seed, rice, lentils, sorghum, beans and even fertilizers). The silobag technology is also being adopted not only in neighbor countries, but also in countries around the world such as the USA, Mexico, South Africa, Australia, Russia and Ukraine, among others.