• Authors:
    • Saulas, P.
    • Ghiloufi, M.
    • Picard, D.
    • de Tourdonnet, S.
  • Source: Field Crops Research
  • Volume: 115
  • Issue: 1
  • Year: 2010
  • Summary: The sustainability of cropping systems can be increased by introducing a cover crop, provided that the cover crop does not reduce the cash crop yield through competition. The cover crop may be sown at the same time as a cash crop in the crop rotation. We carried out an experiment in 1999-2000 and 2000-2001 in the Paris Basin, to analyze the effects of simultaneously sowing winter wheat (Triticum aestivum L.) and red fescue (Festuca rubra L.), a turf grass. Competition between wheat and fescue was analyzed with one variety of red fescue, Sunset, and two varieties of wheat, Isengrain and Scipion, each sown at a density of 150 plants m(-2). In this study, we evaluated the effect of undersown fescue on wheat yield and analyzed the competition between the two species in detail. The undersown red fescue decreased wheat yield by about 12% for Isengrain (8.7 t ha(-1) for undersown Isengrain versus 9.8 t ha(-1) for Isengrain alone) and 7% for Scipion (7.4 t ha(-1) for undersown Scipion versus 8.0 t ha(-1) for Scipion alone). During the early stages of wheat growth (up to the '1 cm ear' stage, corresponding to stage 30 on Zadoks' scale), undersown fescue and fescue sown alone grew similarly. However, fescue biomass levels were much lower (5.6 and 4.7 g m(-2) for fescue grown alone and undersown fescue) than wheat biomass levels on the undersown plots (1120 g m(-2) for Isengrain and 111 g m(-2) for Scipion). From the e1 stage onwards, the wheat canopy rapidly extended, whereas that of red fescue remained sparse. The time lag between the beginning of the rapid increase in LAI and PAR interception by wheat grown alone and that for fescue grown alone was 590 dd in the second year. This resulted in much slower growth rates for undersown fescue than for undersown wheat. Biomass production rate was therefore low for undersown fescue (12% those of fescue grown alone, on average, at the time of wheat harvest), as were levels of water and nitrogen use. Neither the water deficit that occurred during the second experiment nor the nitrogen nutrition status of the wheat on plots with undersown fescue significantly affected wheat biomass production after anthesis. The global interception efficiency index IG epsilon(i) indicated that the fraction of the PAR(o) intercepted by the wheat during its growth (255 days) was 0.35. (C) 2009 Elsevier B.V. All rights reserved.
  • Authors:
    • Meca, A. V.
    • Popescu, N.
  • Source: Annals of the University of Craiova - Agriculture, Montanology, Cadastre Series
  • Volume: 40
  • Issue: 2
  • Year: 2010
  • Summary: Within our country conditions the wheat, rye, barley, oilseed rape and pea-oat fodder are sown in autumn. They may be grown after crops that are harvested during summer or perennial crops or pastures that are included is crop rotation schemes. In the conditions of our country, crops that are harvested during the summer are: pea-oat fodder, pea, early potato, barley and wheat. After harvesting these crops, there must be done, immediately, the summer plowing because the soil is still moist, resulting a good quality plowing. Any delay conducts to diminishing the yields. Usually, the summer plow is made at 18-20 cm depth. Deeper plow are not necessary on most soil types from our country. Twenty cm deeper plow is need only on clayey soil that easily compacts, when the soil is highly infested by weeds, covered by high straw or when in the last year there was made a shallow plow. Summer plow, no matter the depth must be done along with harrow after plow. During the fall, till drilling, the soil has to be harrowed in order to destroy weeds and to maintain soil loosened.
  • 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:
    • Srivastva, A. K.
    • Mina, B. L.
    • Kundu, S.
    • Bhattacharyya, R.
    • Chandra, S.
    • Pandey, S. C.
    • Gupta, S.
    • Saha, S.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 86
  • Issue: 2
  • Year: 2010
  • Summary: To date, the sustainability of wheat ( Triticum aestivum)-soybean ( Glycine max) cropping systems has not been well assessed, especially under Indian Himalayas. Research was conducted in 1995-1996 to 2004 at Hawalbagh, India to study the effects of fertilization on yield sustainability of irrigated wheat-soybean system and on selected soil properties. The mean wheat yield under NPK+FYM (farmyard manure) treated plots was ~27% higher than NPK (2.4 Mg ha -1). The residual effect of NPK+FYM caused ~14% increase in soybean yield over NPK (2.18 Mg ha -1). Sustainable yield index values of wheat and the wheat-soybean system were greater with annual fertilizer N or NPK plots 10 Mg ha -1 FYM than NPK alone. However, benefit:cost ratio of fertilization, agronomic efficiency and partial factor productivity of applied nutrients were higher with NPK+FYM than NPK, if FYM nutrients were not considered. Soils under NPK+FYM contained higher soil organic C (SOC), total soil N, total P and Olsen-P by ~10, 42, 52 and 71%, respectively, in the 0-30 cm soil layers, compared with NPK. Non-exchangeable K decreased with time under all treatments except NPK. Total SOC in the 0-30 cm soil layer increased in all fertilized plots. Application of NPK+FYM also improved selected soil physical properties over NPK. The NPK+FYM application had better soil productivity than NPK but was not as economical as NPK if farmers had to purchase manure.
  • Authors:
    • Dalal, R. C.
    • Blamey, F. P. C.
    • Rao, A. S.
    • Rao, D. L. N.
    • Mohanty, M.
    • Reddy, K. S.
    • Dixit, S. K.
    • Pandey, M.
    • Menzies, N. W.
  • Source: Proceedings of the 19th World Congress of Soil Science, Soil Solutions for a Changing World, 1–6 August 2010, Brisbane, Australia
  • Year: 2010
  • Summary: The Mother Baby Trial (MBT) approach is an on-farm participatory mechanism to introduce and test technology options suited to a heterogeneous community. In this study, the MBT concept was followed with integrated nutrient management (INM) technology in a soybean-wheat system. Seven treatments were tested in Mother trials in 2005-06 and 2006-07 on farmers' fields in the Rajgarh and Bhopal districts of Central India. In 2007-08, 100 Baby trials were conducted by farmers in 10 surrounding villages to demonstrate and test the INM technology. The Baby trials were based on the results of Mother trials which showed that INM using 50% of the recommended NPKS fertilizer+5 t FYM/ha+ Rhizobium to soybean and 75% of the recommended NPKS fertilizer+P-solubilizing bacteria to wheat produced higher soybean yield by 46% and higher wheat yield by 24% over the farmers' practice. In the Baby trials, there was a wide variation in soybean yield obtained with INM, balanced fertilization (BF) using inorganic fertilizers, and farmers' practice; in poorer yielding trials, some problems were evident in the control of weeds and insect pests. Wheat responded well to BF and INM in trials irrigated 3-4 times. The MBT approach proved valuable in demonstrating higher productivity of the soybean-wheat system, and the value of INM and BF technologies, but only with proper weed and pest management in soybean, and adequate irrigation in wheat, as a package of practices.
  • 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:
    • Karp, A.
    • Riche, A.
    • Bohan, D. A.
    • Mallott, M. D.
    • Haughton, A. J.
    • Cunningham, M.
    • Sage, R.
  • Source: Ibis
  • Volume: 152
  • Issue: 3
  • Year: 2010
  • Summary: We compared birds in a group of established and well-managed miscanthus (Miscanthus x giganteus) fields in Somerset and East Devon, southwestern England, with plots of short rotation coppice (SRC) willow, arable crops and grassland in two winters and one summer. Following early spring cutting, 19 miscanthus fields grew taller, initially produced greater cover and were less weedy than SRC. As stubble in May, the miscanthus contained broadly similar species at similar densities to arable and grassland comparison plots. By July, at 2-m-tall, miscanthus held higher densities of birds but of fewer species, most of them characteristic of woodland and scrub. SRC, previously identified as being a beneficial crop for many birds, always contained more species and individuals than miscanthus. Throughout each of two winters, 15 miscanthus plots remained unharvested and contained more wood/scrub species such as Blackbirds Turdus merula, tits, Reed Buntings Emberiza schoeniclus and Woodcock Scolopax rusticola than the comparison plots, which held more corvids and Skylarks Alauda arvensis amongst others. Similar overall mean densities of birds in the miscanthus and the comparison plots masked relatively low density variance in miscanthus and very high variance in the comparison plots. Unharvested miscanthus crops grown in place of habitat types supporting flocks of wintering birds would displace these flocks. Miscanthus plantations with open patches attracted more finches and waders in winter. The two previous studies of birds in miscanthus in the UK found more species and more individuals than we did in summer and winter. Both these studies documented high levels of weediness and patchy crop growth. In the context of this previous work our data suggest that bird use of miscanthus in summer and winter is likely to be variable, affected by region, weediness, crop structure and patchiness. While large-scale cropping of SRC in England is likely to have a positive overall impact on a suite of common farmland and woodland birds, our data suggest that miscanthus in the southwest of England may have an approximately neutral effect. However, some open farmland specialist species may be lost when planting either crop.
  • Authors:
    • Launay, M.
    • Tourdonnet, S. de
    • Shili-Touzi, I.
    • Dore, T.
  • Source: Field Crops Research
  • Volume: 116
  • Issue: 3
  • Year: 2010
  • Summary: The introduction of a living cover crop during a cash crop growth cycle (relay intercropping) and its maintenance after the cash crop harvest may help to preserve biodiversity, increase soil organic matter content and carbon sequestration and provide other ecosystem services, such as natural pest regulation or nutrient recycling, by increasing useful biotic interactions within the agroecosystem. We studied the impact of various approaches to manage a red fescue cover crop in a winter wheat crop in terms of light, water and nitrogen competition, using the STICS crop model adapted for intercropping. The STICS model for wheat/fescue intercropping was first evaluated on two years of experimental data obtained in the field. It gave satisfactory statistical results for the prediction of dry matter, leaf area index (LAI) and nitrogen accumulation in the two species, and for nitrogen and water dynamics in the soil. By simulating unmeasured variables, such as transpiration, the model improves our understanding of the performance of the intercrop in the field. For example, we showed that the intercropping system was more efficient that wheat grown as a sole crop, in terms of nitrogen accumulation and decreasing soil nitrogen levels before the leaching period. However, it also resulted in lower wheat yields. We then used the STICS model to compare four intercropping management scenarios differing in terms of the date of red fescue emergence, over 35 climatic years. We found that, in most climatic scenarios, the emergence of the fescue crop during the late tillering phase of the wheat crop gave the best compromise between wheat yield overall nitrogen accumulation and radiation interception.
  • Authors:
    • Fontaneli, R. S.
    • Santos, H. P. dos
    • Spera, S. T.
    • Tomm, G. O.
  • Source: Acta Scientiarum. Agronomy
  • Volume: 32
  • Issue: 1
  • Year: 2010
  • Summary: Soil physical characteristics were evaluated, after eight years (1995 to 2003), on a typic Hapludox located in Coxilha, Rio Grande do Sul State, Brazil. Six crop production systems were evaluated: system I (wheat-soybean/black oat+common vetch pasture-corn); system II (wheat-soybean/black oat+common vetch+annual ryegrass pasture-corn); system III (wheat-soybean/black oat+common vetch pasture-pearl millet pasture); system IV (wheat-soybean/black oat+common vetch+annual ryegrass pasture-pearl millet pasture); system V (wheat-soybean, white oat-soybean/black oat+common vetch pasture-pearl millet pasture); and system VI (wheat-soybean/white oat-soybean/black oat+common vetch+annual ryegrass pasture-pearl millet pasture). Soil bulk density and resistance to penetration increased from deeper layer (10-15 cm) to top layer (0-5 cm). In the systems I, V and VI, total porosity decreased and soil bulk density resistance to penetration increased from the deeper layers to top layer surface, due to higher intensity of livestock activities. After eight years of use, the production systems under no-till, involving annual winter and summer pastures and crops, did not promoted soil degradation, in constraining levels, on soil physical attributes.