• Authors:
    • Stevens, W.
    • Jabro, J.
    • Sainju, U.
  • Source: Journal of Environmental Quality
  • Volume: 37
  • Issue: 1
  • Year: 2008
  • Summary: Management practices can influence soil CO 2 emission and C content in cropland, which can effect global warming. We examined the effects of combinations of irrigation, tillage, cropping systems, and N fertilization on soil CO 2 flux, temperature, water, and C content at the 0- to 20-cm depth from May to November 2005 at two sites in the northern Great Plains. Treatments were two irrigation systems (irrigated vs. non-irrigated) and six management practices that contained tilled and no-tilled malt barley ( Hordeum vulgaris L.) with 0 to 134 kg N ha -1, no-tilled pea ( Pisum sativum L.), and a conservation reserve program (CRP) planting applied in Lihen sandy loam (sandy, mixed, frigid, Entic Haplustolls) in western North Dakota. In eastern Montana, treatments were no-tilled malt barley with 78 kg N ha -1, no-tilled rye ( Secale cereale L.), no-tilled Austrian winter pea, no-tilled fallow, and tilled fallow applied in dryland Williams loam (fine-loamy, mixed Typic Argiborolls). Irrigation increased CO 2 flux by 13% compared with non-irrigation by increasing soil water content in North Dakota. Tillage increased CO 2 flux by 62 to 118% compared with no-tillage at both places. The flux was 1.5- to 2.5-fold greater with tilled than with non-tilled treatments following heavy rain or irrigation in North Dakota and 1.5- to 2.0-fold greater with crops than with fallow following substantial rain in Montana. Nitrogen fertilization increased CO 2 flux by 14% compared with no N fertilization in North Dakota and cropping increased the flux by 79% compared with fallow in no-till and 0 kg N ha -1 in Montana. The CO 2 flux in undisturbed CRP was similar to that in no-tilled crops. Although soil C content was not altered, management practices influenced CO 2 flux within a short period due to changes in soil temperature, water, and nutrient contents. Regardless of irrigation, CO 2 flux can be reduced from croplands to a level similar to that in CRP planting using no-tilled crops with or without N fertilization compared with other management practices.
  • Authors:
    • Pedersen, J. B.
  • Source: Oversigt over Landsfors<o>gene. Fors<o>g og unders<o>gelser i de land<o>konomiske foreninger, 2008
  • Year: 2008
  • Summary: Following a general account of the weather, land use, application of fertilizers and pest and disease control products, and an overview of the crops grown and their yields, most of the review is devoted to reports on individual crops. These were winter barley, winter rye, triticale, winter wheat, spring barley, oats, spring wheat, peas, grasses, spinach, rape, potatoes, sugarbeet and maize. Other sections cover alternative crops (for bioenergy production), manuring and fertilizers, cultural methods, organic methods, advisory work on plant breeding, tables of approved species and varieties of crop plants, lists of relevant organizations, a list of authors of the sections, and a comprehensive subject index.
  • Authors:
    • Reddy, K. C.
    • Tazisong, I. A.
    • Nyakatawa, E. Z.
    • Senwo, Z. N.
    • Sainju, U. M.
  • Source: Journal of Environmental Quality
  • Volume: 37
  • Issue: 3
  • Year: 2008
  • Summary: Quantification of soil carbon (C) cycling as influenced by management practices is needed for C sequestration and soil quality improvement. We evaluated the 10-yr effects of tillage, cropping system, and N source on crop residue and soil C fractions at 0-to 20-cm depth in Decatur silt loam (clayey, kaolinitic, thermic, Typic Paleudults) in northern Alabama, USA. Treatments were incomplete factorial combinations of three tillage practices (no-till [NT], mulch till [MT], and conventional till [CT]), two cropping systems (cotton [Gossypium hirsutum L.]-cotton-corn [Zea mays L.] and rye [Secale cereale L.]/cotton-rye/cotton-corn), and two N fertilization sources and rates (0 and 100 kg N ha(-1) from NH4NO3 and 100 and 200 kg N ha(-1) from poultry litter). Carbon fractions weresoil organic C (SOC), particulate organic C (POC), microbial biomass C (MBC), and potential C mineralization (PCM). Crop residue varied among treatments and years and total residue from 1997 to 2005 was greater in rye/cottoil-rye/cotton-corn than in cotton-cotton-corn and greater with NH4NO3 than with poultry litter at 100 kg N ha(-1). The SOC content at 0 to 20 cm, after 10 yr was greater with poultry litter than with NH4NO3 in NT and CT, resulting in a C sequestration rate of 510 kg C ha(-1) yr(-1) with poultry litter compared with -120 to 147 kg C ha(-1) yr(-1) with NH4NO3. Poultry litter also increased PCM and MBC compared with NH4NO3. Cropping increased SOC, POC, and PCM compared with fallow in NT Long-term poultry litter application or continuous cropping increased soil C storage and microbial biomass and activity compared with inorganic N fertilization or fallow, indicating that these management practices can sequester C, offset atmospheric CO2 levels, and improve soil and environmental quality.
  • Authors:
    • Moraes, A.
    • Balbinot Junior, A.
    • Backes, R.
  • Source: PLANTA DANINHA
  • Volume: 25
  • Issue: 3
  • Year: 2007
  • Summary: Straw on the soil significantly reduces weed infestation under no-tillage system. The potential of winter cover crops and their management timing in reducing weed infestation in maize crop were studied in Canoinhas, Santa Catarina, Brazil, in 2003/04 and 2004/05. In the first experiment, 6 winter cover crops were investigated: oilseed radish, black oat [ Avena nuda], rye, ryegrass [ Lolium sp.], intercropped among black oat and common vetch [ Vicia sativa] and among oilseed radish, black oat, rye, ryegrass and common vetch. These cover crops were slashed down at three different times before maize sowing (1, 10 and 25 days). In the second experiment, the potential to reduce weed infestation was investigated in the 6 cover crops previously mentioned, plus the common vetch. The straw of ryegrass and from intercropping among the 5 species used had a high capacity to suppress weed emergence and dry matter production, while oilseed radish straw showed low weed suppression potential. The winter cover crops slashed down next to maize sowing decreased the weed infestation.
  • Authors:
    • Backes, R.
    • Moraes, A.
    • Balbinot Junior, A.
    • Souza, A.
  • Source: Scientia Agraria
  • Volume: 8
  • Issue: 2
  • Year: 2007
  • Summary: A study was undertaken in Canoinhas, Santa Catarina, Brazil, during 2004/05 season to evaluate the effect of cover crop desiccation time in relation to maize sowing on the weed infestation and maize yield. Ryegrass ( Lolium multiflorum) as a single crop and in an intercropping system (rye grass+black oat ( Avena strigosa [ A. nuda])+rye+common vetch ( Vicia sativa)+oilseed radish) were desiccated 5 times at 1, 10 20 and 30 days before maize sowing. Cover crop management near maize sowing decreased the density and mass accumulation of weeds and improved the maize grain yield.
  • Authors:
    • Weiss, M. J.
    • Pike, K. S.
    • Buntin, G. D.
    • Webster, J. A.
  • Source: Handbook of small grain insects
  • Year: 2007
  • Summary: This handbook is designed primarily for the practitioners of integrated pest management programmes in small grains, growers, crop consultants, extension agents, and company agronomists and sales representatives. Its primary objective is to provide fundamental and useful information about managing (through cultural, plant resistance, biological and chemical methods) small grain insects throughout the United States and Canada. Although it focuses on insect pests of small grains, noninsect pests (e.g. mites) also are covered. Crops covered in this handbook are wheat, barley, oats, rye and triticale, with an emphasis on wheat. The first three sections provide information about small grains and their production, principles and practices of small grain insect management, and an overview of the pest injury to small grains by insects, weeds, and plant pathogens. The remainder of the handbook is devoted to discussions of insect and mite pests of small grains and to beneficial organisms, including insect pathogens, parasitoids and predators.
  • Authors:
    • Puzynski, S.
    • Wrzesinska, E.
    • Dzienia, S.
  • Source: Folia Universitatis Agriculturae Stetinensis
  • Volume: 255
  • Issue: 2
  • Year: 2007
  • Summary: Drawski Landscape Park is located in the centre of Drawskie Lake District in the Zachodniopomorskie Voivodship, Poland. The park covers 41 430 ha with 10.5% of lakes belonging to the following communes: Barwice, Borne Sulinowo, Czaplinek, Ostrowice, Poczyn Zdroj and Zocieniec. The condition for agricultural production in these communes are mostly medium-favourable. Soils have predominately medium as well as poor and very poor properties. The land use in administrative boundaries of the communes is varied, the lowest share of agricultural area at 19.6% is in Borne Sulinowo commune whereas the highest at 50.2% is in Barwice. In agricultural land use structure, the share of arable land among communes ranged from 82.4% in Borne Sulinowo to 88.3% in Czaplinek, and grasslands from 11.6% in Czaplinek, to 17.5% in Borne Sulinowo. Relatively high share of afforestated areas (30.0-57.3%), as well as low population density (17-81 persons per km 2), favours development of tourism in these communes. Small farms (with less than 5 ha of agricultural land) are dominant and they operate on poor soils which causes problems. Areas sown with cereals have been recorded at 76.7-89.3%, potatoes at 1.6 to 6.8%, industrial crops at 2.8 to 12.1% and fodder crops at 0.4 to 8.7%. The major crops among cereals are rye- 24.1 to 49.2% and wheat- 17.7 to 35.2%. The biggest share (26.4%) of oat among cereals is in Barwice commune. The share of potato is in the range of 1.6-6.8%, whereas oilseed rape and agrimony is planted on 2.8 to 12.1% of sown area. The number of livestock unit per 100 ha of agricultural area is very low (12.0-29.0 LU), which do not provide the required amount of manure.
  • Authors:
    • Agenbag, G. A.
    • Louw, P. J. E.
    • Fourie, J. C.
  • Source: South African Journal of Enology and Viticulture
  • Volume: 28
  • Issue: 2
  • Year: 2007
  • Summary: The trial was conducted over a period of ten years (1993/94 to 2002/03) on a sandy soil in a Sauvignon blanc/Ramsey vineyard near Lutzville (31degrees35′S, 18degrees52′E), situated in the semi-arid Olifants River Valley of the Western Cape. Fourteen treatments, consisting of three grain species and four legumes, managed according to two cover crop management practices, were included. One management practice consisted of cover crops which were sown annually and full surface, post-emergence chemical control which was applied before bud break and when the berries reached pea size (BB). The second management practice consisted of cover crops which were sown biennially. Post-emergence chemical control was applied to the vine row before bud break and full surface when the berries reached pea size (AB). From 1999/2000 to 2002/03 the cover crops were sown annually, while the full surface post-emergence control applied at the end of November was advanced to mid-October. Two treatments in which Avena sativa L. v. Saia ('Saia' oats) and Vicia dasycarpa Ten. (grazing vetch) were sown annually, controlled mechanically in the work row and chemically in the vine row from bud break to harvest (MC), were also applied. These treatments were compared to a control, in which no cover crop was sown and MC was applied. A treatment in which no cover crop was sown and BB was applied (weedchem), was also included. During the third growing season of the vines (1994/95), the grapevine shoot mass of the BB treatments of grazing vetch and Medicago truncatula Gaertn. v. Paraggio ('Paraggio' medic) was significantly more than that of the AB and MC treatments, with the exception of Secale cereale L. v. Henog (AB) and grazing vetch (MC). The first harvest (1994/95) from the grapevines in the BB treatments was significantly higher than that of weedchem and the MC treatments. The grape yield of the BB treatments, grazing vetch (AB) and Ornithopus sativus L. v. Emena (pink Seradella) (AB) was significantly more than that of weedchem and the control during the 1997/98 season. The NO 3-N concentration in the leaf petioles in all the cover crop treatments was, with the exception of the AB treatments of rye, M. truncatula Gaertn. v. Parabinga ('Parabinga' medic) and grazing vetch, significantly higher than that in weedchem and the control, as measured during the 1994/95 season. The NO 3-N concentration in the leaf petioles of the BB and AB treatment of a species differed significantly. The N concentration in the juice of the cover crop treatments during the 1995/96 season was, with the exception of 'Saia' oats (MC) and 'Parabinga' medic (AB), significantly higher than that of weedchem and the control. During the 1998/99 season, the N concentration of the juice in the BB and AB treatments of grazing vetch and pink Seradella was significantly higher than that of the MC treatments, two rye treatments, weedchem and the AB treatments of the other cover crops. The concentration of Ca in the juice of the cover crop treatments was, with the exception of the pink Seradella treatments, significantly higher than that of weedchem and the control. Wine quality did not differ between treatments.
  • Authors:
    • Bateman, G.
    • Jenkyn, J.
    • Gutteridge, R.
  • Source: Annals of Applied Biology
  • Volume: 150
  • Issue: 1
  • Year: 2007
  • Summary: Take-all disease ( Gaeumannomyces graminis var. tritici) in wheat crops is known to be suppressed by naturally occurring antagonistic fungi, closely related to the pathogen, that infect grasses and cereals. This form of suppression was re-investigated because of the changing importance and role of grass weeds and grass covers in arable farming. Natural populations of the competitive fungus Gaeumannomyces cylindrosporus, allowed to develop under rye-grass, were more effective than artificially introduced populations in suppressing the development of take-all in following wheat crops. To be effective, the antagonist needs to be present before the start of wheat cropping. Introducing G. cylindrosporus, but not G. graminis var. graminis (a potential antagonist that is faster growing), into a previous crop, or just after the previous crop, sometimes suppressed take-all, but the effect was small. It is concluded that, for any future attempts at biocontrol by these fungi, they should be introduced into a preceding crop not susceptible to take-all. Take-all inoculum in the soil should be at a minimum and effective hosts of the take-all pathogen must not be present as weeds or volunteers.
  • Authors:
    • Pedersen, J. B.
  • Source: Oversigt over Landsfors<o>gene 2007. Fors<o>g og unders<o>gelser i de land<o>konomiske foreninger
  • Year: 2007
  • Summary: Work conducted by Landsforsgene, a collaborative body that undertakes field trials and experiments on crop plants in Denmark, is reported. A general introduction gives details of conditions in the 2007 growing season (warmer in spring and wetter than usual in summer), and their effects on factors such as the efficacy of fertilizer application and the harvest. The aim is to give growers a basis for future planning, taking account of environmental conditions and profitable plant production. Most of the report is devoted to separate sections covering individual crops: winter barley, winter rye, triticale, winter wheat, spring barley, oats, spring wheat, field peas, grass seeds, rape, hemp, spinach, strawberries, potatoes, sugar beet, pasture plants (grasses and clovers), and maize. Within these sections details of varieties, fertilizers, weeds, and diseases are provided in the text and in numerous tables and photographs. Other small sections deal with topics including organic production, fertilizers, plant breeding, statistical methods, policies, and names and addresses of suppliers. The report concludes with a list of the 23 authors of sections, and a comprehensive index.