• Authors:
    • Kayisoglu, B.
    • Yalcn, H.
    • Koc, F.
    • Gonulol, E.
    • Bayhan, Y.
  • Source: Farm work science facing the challenges of the XXI century. Proceedings XXIX CIOSTA-GIGR V Congress, Krakow, Poland, 25-27 June, 2001, p. 30-35
  • Volume: 10
  • Year: 2001
  • Summary: The effect of different tillage methods on silage quality in second crop maize for silage was determined in this study. For this purpose, second crop maize was planted by using the following tillage methods: (1) Direct drilling (no-till) (DRD); (2) Heavy duty disc harrow+pneumatic precision drill (DIS); (3) Plough+disc harrow+roller+pneumatic precision drill (PLO); (4) Rotary tiller+pneumatic precision drill (ROT); (5) Tillage combination+pneumatic precision drill (TIC); and (6) Irrigation+Plough+disc harrow+roller+pneumatic precision drill (conventional) (CON). After harvesting, plant samples were filled into PVC silos (with three replication for each treatment) for fermentation and kept in these silos for 75 days. Significant statistical differences were found between treatments (tillage methods) according to pH, DM (dry matter), CA (crude ash), CF (crude fibre), WSC (water soluble carbohydrate), NH 3-N 3 and LAB (lactic acid batteries). Quality parameters in all treatments remained between the desired levels. No-tillage method with DRD and minimum tillage methods with ROT and TIC can be suggested.
  • Authors:
    • Khosla, R.
    • Alley, M. M.
    • Davis, P. H.
  • Source: Agronomy Journal
  • Volume: 92
  • Issue: 2
  • Year: 2000
  • Summary: Grain sorghum [Sorghum bicolor (L.) Moench] is grown in rotation with wheat (Triticum aestivum L.) and soybean [Glycine mar (L.) Merr.] in the mid-Atlantic Sufficient data on N fertilization of sorghum are not available for this region. Our objective was to evaluate the influence of multi-rate N fertilization on dryland sorghum. Treatments consisted of factorial combinations of four starter-band N rates (11, 34, 56, and 78 kg N ha(-1)) and four sidedress N rates (0, 45, 90, and 134 kg N ha(-1)). A broadcast treatment of 67 kg N ha(-1) at planting was also included. Starter-band was applied 5 cm to the side and below the seed. Sidedress was applied 35 days after emergence at the eight-leaf growth stage. Grain yield ranged from 1.7 to 11.9 Mg ha(-1) over eight site-years and was responsive and nonresponsive to N applications on four sites each. Nonresponsiveness was either due to high levels (>85 kg N ha(-1)) of residual soil mineral N, or severe water stress conditions. Our results indicate that production of sorghum on soils testing high in mineral N (50 kg N ha(-1) in the surface 0.3 m) at planting should not receive any starter-band N in conjunction with sidedress N application of 130 kg N ha(-1) for optimum economic return to N fertilization. For soils testing low in mineral N, 40 kg N ha(-1) starter-band in conjunction with 130 kg N ha(-1) sidedress N should optimize the sorghum yields in most situations.
  • Authors:
    • Mrabet,R.
  • Source: Field Crops Research
  • Volume: 66
  • Issue: 2
  • Year: 2000
  • Summary: Low unreliable rainfall and high evaporation potential in semiarid parts of Morocco, but also inappropriate management of soil resources, pl produce erratic crop yields and uncertain economic returns. The need to maximize soil water conservation and optimize wheat grain production in Moroccan dryland areas have contributed to the emergence of direct seeding technology in this region. A field experiment was conducted to investigate the effects of no-till, minimum till, traditional and deep tillage systems on wheat yield as well as on water use efficiency. The experiment was conducted from 1995 to 1999, under rainfall regimes that varied from as low as 195 mm to 440 mm. Grain yields under no-tillage (2.47 Mg ha(-1)) were equal to those obtained using a chisel plow or deep tillage and superior to yields obtained by rotovating, conventional off-set disking, stubble mulching ol subsurface traditional tillage. Water use efficiency (6.6-7.1 kg mm(-1) ha(-1)) was similar following no-till, deep disking and chisel plowing while other tillage systems had lower but similar values (varying from 5.4 to 5.9 kg mm(-1) ha(-1)). Tillage systems did not differ significantly in terms of total dry matter or straw production and water use. Improvements in notill drill design, which focus on proper seed and fertilizer placement and which prevent seed and straw being placed in close contact, an needed and may contribute to enhanced wheat yield and biomass under no-tillage.
  • Authors:
    • Nyakatawa,E. Z.
    • Reddy,K. C.
  • Source: Agronomy Journal
  • Volume: 92
  • Issue: 5
  • Year: 2000
  • Summary: Inadequate and less vigorous crop stand is a constraint to adoption of conservation tillage in cotton (Gossypium hirsutum L.) production. We evaluated the effects of tillage (conventional till, mulch-till, no-till), cropping system (cotton-winter fallow, cotton-winter rye, Secale cereale L.), and N source and rate (ammonium nitrate and poultry litter; 0, 100, and 200 kg N ha(-1)) on rotten seedling emergence on a Decatur silt loam soil (Typic Paleudults) in northern Alabama, from 1996 to 1998. Cotton seedling counts under no-till were 40 to 150% greater than those under conventional till at 1 and 2 d during seedling emergence. Cotton-winter rye cropping system had 14 to 50% greater seedling counts than cotton-winter fallow cropping during the first 4 d of emergence in 1998. Poultry litter source of N gave 17 to 50% greater cotton seedling counts than ammonium nitrate during the first 4 d of emergence in 1998, In all these cases, the differences progressively narrowed down by the 4th day of seedling emergence. Cotton seedling counts were significantly correlated to cotton growth parameters and lint yield, especially in the drier year (1998). These results were attributed to soil moisture conservation during seedling emergence. Our results show that conservation tillage improved cotton germination, emergence, dry matter, and lint yield. Therefore, no-till with winter rye cover cropping and poultry litter can be used for achieving early cotton seedling emergence and growth in the U.S. cotton belt where dryland cotton production systems are on the increase and safe disposal of poultry litter is becoming an environmental problem.
  • Authors:
    • Swanton, C.
    • Vyn, T. J.
    • Hooker, D. C.
    • Weersink, A.
    • Yiridoe, E. K.
  • Source: Canadian Journal of Agricultural Economics
  • Volume: 48
  • Issue: 2
  • Year: 2000
  • Summary: Conservation tillage systems have not been widely adopted on clay soils. There are few empirical studies on the production potential and economic feasibility of conservation tillage systems for corn (Zea mays L.) and soybean (Glycine max L.) production on clay soils. On some soils in some regions, crop yields and possibly profitability can be increased and yield and net farm returns risks may be reduced through the use of conservation tillage systems. Stochastic dominance efficiency criteria are used to rank net return distributions for one conventional tillage (CT) and seven conservation tillage (including five reduced tillage and two no-till) systems conducted for corn and soybean cropping systems on two clay soils located in the 3050 to 3100 Corn Heat Unit areas of Ontario. Average yields are similar under conventional tillage and reduced tillage systems, although actual corn and soybean yield response to tillage treatment is affected by drought (year). Average net returns differ among tillage treatments due to two factors. First, actual corn and soybean yields vary among tillage systems for each soil type, depending on weather (i.e., year) effects. In addition, machinery costs that are crop-specific increase costs of production and therefore reduce net returns In general, CT systems dominate both reduced tillage and no-till systems for almost all risk intervals for both clay soils, except for slightly high-risk-preferring intervals.
  • Authors:
    • Hulugalle, N. R.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 31
  • Issue: 5-6
  • Year: 2000
  • Authors:
    • Tanaka, D. L.
    • Halvorson, A. D.
    • Black, A. L.
    • Krupinsky, J. M.
    • Merrill, S. D.
    • Wienhold, B. J.
  • Source: Agronomy Journal
  • Volume: 92
  • Issue: 2
  • Year: 2000
  • Summary: Spring wheat (Triticum aestivum L.) production in the northern Great Plains generally utilizes conventional tillage systems. A 12-yr study evaluated the effects of tillage system [conventional-till (CT), minimum-till (MT), and no-till (NT)], N fertilizer rate (0, 22, and 45 kg N ha(-1)), and cultivar (Butte86 and Stoa) on spring wheat grain yields in a dryland spring wheat-fallow rotation (SW-F). Butte86 yields with CT exceeded NT yields in five out of 12 years with 0 and 22 kg N ha(-1) applied, and four years with 45 kg N ha(-1) applied. Stoa yields with CT exceeded NT yields in three out of 12 years with no N applied, four years with 22 kg N ha(-1) applied, and only one year with 45 kg N ha(-1) applied. Yields with NT exceeded those with CT in one year. Most years, yields with MT equaled those with CT. Responses to N tended to be greatest in years when spring soil NO3-N was lowest. Positive yield responses to N fertilization with CT occurred in three years with Butte86 and two years with Stoa; with MT, four years with Butte86 and two years with Stoa; and with NT, five years with Butte86 and three years with Stoa. Cultivars were not consistent in their response to tillage and N fertilization. These results indicate that farmers in the northern Great Plains can successfully produce spring wheat in a SW-F system using MT and NT systems, but yields may be slightly reduced when compared with CT systems some years.
  • Authors:
    • Reule, C. A.
    • Halvorson, A. D.
    • Anderson, R. L.
  • Source: Journal of Soil and Water Conservation
  • Volume: 55
  • Issue: 1
  • Year: 2000
  • Summary: Minimum-till (MT) and no-till (NT) systems were evaluated for converting seeded grassland back to cropland. Nitrogen fertilization needs to optimize grain yields following grass and to optimize hay yields from the grassland were also evaluated. Tillage treatments - conventional till (CT), MT, and NT- were established on a Weld silt loam soil that had been seeded to grass about 30 yr following more than 30 yr of crop-fallow. Nitrogen treatments were 0, 45, and 30 kg N/hn (0, 40, and 80 lb N/a) applied to each crop in a winter wheat (Triticum aestivum L.)-corn (Zea mays L.)-fallow rotation or annually to grass plots. Residue cover at wheat planting averaged 18, 44, and 73% for CT; MT; and NT; respectively Soil water recharge was minimal between grass kill and wheat planting; however soil NO3-N increased 115, 63, and 54 kg N/ha (103, 62, and 48 lb N/ac) for CT, MT, and NT respectively. Wheat grain yields were greater with CT 2,685 kg/ha (40 bu/ac) and MT 2,558 kg/ha (38 bu/ac) than with NT 2,052 kg/ha (30.5 bu/ac). Lower wheat yields with NT resulted from lack of grass control Wheat yield responses to N varied with year and were dependent on available water supplies. Corn grain yields were low, [1,233, 2,063, and 1,564 kg/ha (19.7, 32.9, and 24.9 bu/ac) for CT; MT, and NT; respectively] due to limited growing season water. Average wheat 6,298 kg/ha (5,623 lb/ac) and corn 5,040 kg/ha (4,500 lb/ac) phytomass production exceeded that of the fertilized grass [1,529 kg/ha with 90 kg N/ha (1,365 lb/ac with 80 lb N/ac)]. Producers converting CRP grass to crop production can use MT and NT practices to maintain soil erosion control.
  • Authors:
    • Hunt, H. W.
    • Elliott, E. T.
    • Six, J.
    • Paustian, K.
  • Source: Biogeochemistry
  • Volume: 48
  • Issue: 1
  • Year: 2000
  • Summary: Crop-based agriculture occupies 1.7 billion hectares, globally, with a soil C stock of about 170 Pg. Of the past anthropogenic CO2 additions to the atmosphere, about 50 Pg C came from the loss of soil organic matter (SOM) in cultivated soils. Improved management practices, however, can rebuild C stocks in agricultural soils and help mitigate CO2 emissions. Increasing soil C stocks requires increasing C inputs and/or reducing soil heterotrophic respiration. Management options that contribute to reduced soil respiration include reduced tillage practices (especially no-till) and increased cropping intensity. Physical disturbance associated with intensive soil tillage increases the turnover of soil aggregates and accelerates the decomposition of aggregate-associated SOM. No-till increases aggregate stability and promotes the formation of recalcitrant SOM fractions within stabilized micro- and macroaggregate structures. Experiments using 13C natural abundance show up to a two-fold increase in mean residence time of SOM under no-till vs intensive tillage. Greater cropping intensity, i.e., by reducing the frequency of bare fallow in crop rotations and increasing the use of perennial vegetation, can increase water and nutrient use efficiency by plants, thereby increasing C inputs to soil and reducing organic matter decomposition rates. Management and policies to sequester C in soils need to consider that: soils have a finite capacity to store C, gains in soil C can be reversed if proper management is not maintained, and fossil fuel inputs for different management practices need to be factored into a total agricultural CO2 balance.
  • Authors:
    • Raper, R. L.
    • Runion, G. B.
    • Reeves, D. W.
    • Reicosky, D. C.
    • Prior, S. A.
  • Source: Soil & Tillage Research
  • Volume: 54
  • Issue: 3-4
  • Year: 2000
  • Summary: Recent research indicates tillage operations result in a rapid physical release of CO2 and water vapor from soil. However, effects of soil disturbance on gas fluxes during planting operations have not been adequately explored. Our objective was to measure short-term gas loss resulting from the use of different planting preparation implements on long-term residue-covered soil (no-till) on a Norfolk loamy sand (Typic Kandiudults; FAO classification Luxic Ferralsols) in east-central Alabama, USA. A crimson clover (Trifolium incarnatum L.) cover crop was killed with herbicide two weeks prior to the study. Due to dry soil conditions, 15 mm of water was applied 24 h prior to study. Gas fluxes were measured with a large canopy chamber (centered over two rows) for an integrated assessment of equipment-induced soil disturbance. Increased losses of CO2 and water vapor were directly related to increases in soil disturbance. Although these short-term C losses are minor in terms of predicting longterm C turnover in agro-ecosystems, results suggest that selecting planting equipment that maintains surface residue and minimizes soil disturbance could help to conserve soil water needed for successful seedling establishment in these coarse textured soils. Published by Elsevier Science B.V.