• Authors:
    • Kornecki, T. S.
    • Place, G. T.
    • Reberg-Horton, S. C.
    • Grossman, J. M.
    • Meijer, A. D.
    • Price, A. J.
    • Webster, T. M.
  • Source: Renewable Agriculture and Food Systems
  • Volume: 27
  • Issue: 1
  • Year: 2012
  • Summary: Organic systems in the southeastern USA offer unique challenges and solutions to crop production due to regional soil and climate characterized by highly weathered soil types, high precipitation and the capacity to grow cover crops in the winter. Recently, the interest of producers and researchers in high-residue cover crops and conservation tillage systems has increased. Various designs of the roller-crimper to manage cover crops have been invented and demonstrated to growers in the southeastern region of the USA over the past 17 years. The impacts of high-residue cover crop mulches on the agronomic systems in the region are diverse. Legume cover crops assist with meeting N demand from cash crops though they decompose rapidly and are seldom sufficient for N demanding crops such as corn. Cereal cover crop mulches can have the opposite effect by immobilizing N and have a longer impact on soil moisture and weed dynamics. While undesirable for many crops, N immobilization is one possible mechanism for weed suppression in legume cash crops planted into cereal residues. Other cover crop weed suppression mechanisms include physical impedance, light availability, allelopathy and microclimate effects. Regardless of the cause, successful weed control by mulches is highly dependent on having substantial biomass. The southeastern region is capable of producing cover crop biomass in excess of 9000 kg ha(-1), which is sufficient for weed control in many cash crops, although supplementary weed control is sometimes necessary. Long-term data are needed to predict when farmers should add supplementary weed control. More work is also needed on how much additional N is required for the cash crops and how best to deliver that N in a high-residue environment using organic sources.
  • Authors:
    • Nyakatawa, E. Z.
    • Reddy, S. S.
    • Reddy, C. K.
  • Source: International Journal of Agriculture & Biology
  • Volume: 14
  • Issue: 1
  • Year: 2012
  • Summary: Nitrogen uptake pattern by cotton (Gossypium hirsutum L.) at different growth stages in response to long-term application of poultry litter (PL) in a no-till system (NT) was studied on a silt loam soil in 2009. The study was done in plots that were established in 1996 at TVREC, Belle Mina, AL, USA. Treatments included were three tillage [conventional tillage (CT), mulch-tillage (MT), and no-tillage (NT)] two cropping systems tot ton-lye (C-R; cotton in summer & cereal rye cover crop in winter), and cotton-fallow (C-F; cotton in summer & fallow in winter)] and two sources of nitrogen [PL at 100 and 200 kg N ha(-1) and ammonium nitrate (AN) at 100 kg N ha(-1)] Out of all treatment combinations only 11 important treatments were selected and arranged in a randomized complete block design and replicated 4 times. Results in 2009, showed that NT system can supply equal quantity of nitrogen compared to CT at all growth stages. No-tillage recorded similar growth, yield and total nitrogen uptake compared to CT. Application of PL at 100 kg N ha(-1) showed significantly superior plant growth compared to AN at early growth stage, but the differences disappeared as the plant growth progressed. Similar yields and nitrogen uptake were observed with application of either PL or AN at 100 kg N ha(-1). Application of a double rate of PL (200 kg N ha(-1)) resulted in significantly higher nitrogen uptake compared to that of PL or AN at 100 kg N ha(-1), but a significant yield advantage was not observed with this higher rate. Of the total nitrogen extracted by cotton at maturity, 50% uptake was completed by early flowering stage and 97% was completed by boll development stage. At maturity, the majority of nitrogen (52%) was partitioned into seeds, while the rest was distributed into leaves (16%), stems (18%) and reproductive parts (14%). winter rye cover crop did not influence nitrogen uptake. (C) 2012 Friends Science Publishers
  • Authors:
    • Frigo, E. P.
    • Marins, A. C. de
    • Santos, R. F.
    • Souza, S. N. M. de
    • Borsoi, A.
    • Secco, D.
  • Source: Journal of Food, Agriculture, and Environment
  • Volume: 10
  • Issue: 1; Part 2
  • Year: 2012
  • Summary: Soil organic matter is of fundamental importance to improve the structure and retention of water and nutrients. This assay aims at evaluating the dynamic of organic matter in a clayey oxisol under three tillage systems, five periods and in five depths. The experiment was conducted in the Experimental Center of Agricultural Engineering in the State University of Western Parana (UNIOESTE), in Cascavel city, Parana, Brazil, in a red latosol (usually known as oxisol) from clayey to very clayey texture (600 g kg -1 clay; 320 g kg -1 silt and 80 g kg -1 sand) basalt substrate and soft-wavy relief. The area is geographically set by the coordinates 24degrees48′ south latitude and 53degrees26′ west longitude, 760 m average height. The treatments were composed of three soil tillage systems: CT conventional tillage=disc plowing followed by harrowing to level; RT reduced tillage=scarification without a following harrowing to level; and NT no-till farming=implantation of crops on the stubble of the previous crop. The depths of soil sample extractions, for the determination of organic carbon content, in each tillage system, were as follows: 0.0-0.025; 0.025-0.05; 0.05-0.10; 0.10-0.20 and 0.20-0.30 m. Organic carbon content was determined in accordance with the Walkley-Black methodology, from years 2006 to 2010. The experimental design used was a 5*3*5 factorial (five periods, three tillage systems and five depths). Tukey's test was applied to compare the average of treatments, with the significance level at 5%. After five years, NT showed an increase of 3.5% and 4.8% in organic carbon contents, related to CT and to RT, respectively.
  • Authors:
    • Shirtliffe, S. J.
    • Johnson, E. N.
  • Source: Renewable Agriculture and Food Systems
  • Volume: 27
  • Issue: 1
  • Year: 2012
  • Summary: Organic farmers in western Canada rely on tillage to control weeds and incorporate crop residues that could plug mechanical weed-control implements. However, tillage significantly increases the risk of soil erosion. For farmers seeking to reduce or eliminate tillage, potential alternatives include mowing or using a roller crimper for terminating green manure crops (cover crops) or using a minimum tillage (min-till) rotary hoe for mechanically controlling weeds. Although many researchers have studied organic crop production in western Canada, few have studied no-till organic production practices. Two studies were recently conducted in Saskatchewan to determine the efficacy of the following alternatives to tillage: mowing and roller crimping for weed control, and min-till rotary hoeing weed control in field pea ( Pisum sativum L.). The first study compared mowing and roller crimping with tillage when terminating faba bean ( Vicia faba L.) and field pea green manure crops. Early termination of annual green manure crops with roller crimping or mowing resulted in less weed regrowth compared with tillage. When compared with faba bean, field pea produced greater crop biomass, suppressed weeds better and had less regrowth. Wheat yields following pea were not affected by the method of termination. Thus, this first study indicated that roller crimping and mowing are viable alternatives to tillage to terminate field pea green manure crops. The second study evaluated the tolerance and efficacy of a min-till rotary harrow in no-till field pea production. The min-till rotary hoe was able to operate in no-till cereal residues and multiple passes did not affect the level of residue cover. Field pea exhibited excellent tolerance to the min-till rotary hoe. Good weed control occurred with multiple rotary hoe passes, and pea seed yield was 87% of the yield obtained in the herbicide-treated check. Therefore, this second study demonstrated that min-till rotary hoeing effectively controls many small seeded annual weeds in the presence of crop residue and thus can reduce the need for tillage in organic-cropping systems.
  • Authors:
    • Bortoluzzi, T.
    • Silva, C. A. T. da
    • Arieira, C. R. D.
    • Silva, T. R. B. da
  • Source: African Journal of Agricultural Research
  • Volume: 7
  • Issue: 2
  • Year: 2012
  • Summary: Poultry manure, applied like organic fertilizer on corn, has not been studied extensively; so, no one knows its effect on the genealogy of the soil. However, organic fertilizer does not cost much, it is easy to buy and it has less degree of environmental degradation as compared to chemical fertilizers. This study was conducted in the commercial fields of St. Helena/PR with corn, using the triple hybrid 2B688, established in 2008 with no-till farming for seven years in order to evaluate the effect of poultry manure on corn yield. The treatment used was chemical fertilizer having nitrogen in the formulation NPK with an addition of three doses of poultry manure (0, 3.5 and 7 t ha -1) and a witness; whereas the experimental design was randomized blocks with split plots and five replications. It was observed that the results were not significant for the number of rows per ear and grains per spike. Nevertheless, increased yield in corn was observed with 100% of poultry manure.
  • Authors:
    • Roger-Estrade, J.
    • Basch, G.
    • Moreno, F.
    • Soane, B. D.
    • Ball, B. C.
    • Arvidsson, J.
  • Source: Soil & Tillage Research
  • Volume: 118
  • Year: 2012
  • Summary: Recent literature on no-till is reviewed with particular emphasis on research on commercial uptake and environmental concerns in northern, western and south-western Europe. Increased interest in no-till, and minimum or reduced tillage, results from changes in the economic circumstances of crop production, the opportunity to increase the area of more profitable autumn-sown crops and increased concern about environmental damage associated with soil inversion by ploughing. Highly contrasting soil and climate types within and between these regions exert a strong influence on the success of no-till. While no-till may often result in crop yields which equal or exceed those obtained after ploughing, modest reductions in yield may be tolerated if production costs are lower than with ploughing. The relative costs of fuel and herbicides have changed appreciably in recent years making no-till more attractive commercially. While effective weed control is an essential aspect of no-till, current herbicide technology may not yet fully achieve this. In northern regions no-till usually allows earlier drilling of winter-sown crops but will give lower soil temperature and higher moisture content in spring, causing delayed drilling of spring-sown crops. No-till soils have greater bulk density and bearing capacity than ploughed soils with a pronounced vertical orientation of macroporosity allowing penetration of roots and water, especially in view of the increased population of deep-burrowing earthworms. Particular care must be taken with no-till to minimise soil damage at harvest and to ensure the even distribution of crop residues prior to drilling. Reduced erosion and runoff after adoption of no-till are widely observed and are of particular importance in southwestern Europe. No-till reduces losses of phosphorus in runoff and, in some cases, reduces the loss of nitrate through leaching. Emissions of greenhouse gases CO 2 and N 2O from no-till soils are highly variable and depend on complex interactions of soil properties. Emission of CO 2 from fuel during machinery usage is always appreciably reduced with no-till. Increased soil organic carbon in surface layers of no-till soils is widely found but may not be associated with increased carbon sequestration throughout the profile. The evaluation of the relative carbon balance for no-till and ploughing depends upon complex inter-relationships between soil and climate factors which are as yet poorly understood. Adoption of no-till could be encouraged by government financial assistance in recognition of environmental benefits, although future restrictions on the use of herbicides may be a deterrent. Opportunities for further research on no-till are outlined.
  • Authors:
    • Robertson, G.
    • Tausig, J.
    • Hamilton, S.
    • Basso, B.
    • Syswerda, S.
  • Source: Agricultural Ecosystems and Environment
  • Volume: 149
  • Year: 2012
  • Summary: Nitrate (NO 3-) loss from intensively farmed cropland is a long-standing, recalcitrant environmental problem that contributes to surface and groundwater pollution and coastal zone hypoxia. Here nitrate leaching losses are reported from nine replicated cropped and unmanaged ecosystems in southwest Michigan, USA. Ecosystems include four annual corn-soybean-winter wheat rotations under conventional, no-till, reduced-input, and organic/biologically-based management, two perennial cropping systems that include alfalfa and hybrid poplar trees, and three unmanaged successional communities including an early successional community analogous to a cellulosic biofuel system as well as a mature deciduous forest. The organic, alfalfa, and unmanaged systems received no synthetic, manure, or compost nitrogen. Measured nitrate concentrations were combined with modeled soil water drainage to provide estimates of nitrate lost by leaching over 11 years. Among annual crops, average nitrate losses differed significantly ( pno-till (41.33.0)>reduced-input (24.30.7) > organic (19.00.8) management. Among perennial and unmanaged ecosystems, nitrate loss followed the pattern alfalfa (12.81.8 kg N ha -1 yr -1)=deciduous forest (11.04.2) >> early successional (1.10.4)=mid-successional (0.90.4) > poplar (<0.010.007 kg N ha -1 yr -1) systems. Findings suggest that nitrate loss in annual row crops could be significantly mitigated by the adoption of no-till, cover crops, and greater reliance on biologically based inputs, and in biofuel systems by the production of cellulosic rather than grain-based feedstocks.
  • Authors:
    • Tessier, D.
    • Curmi, P.
    • Guimaraes, M.
    • Tavares Filho, J.
  • Source: REVISTA BRASILEIRA DE CIENCIA DO SOLO
  • Volume: 36
  • Issue: 1
  • Year: 2012
  • Summary: It is known that any kind of soil management causes changes in the soil physical characteristics and can affect agricultural yield. The purpose of this study was to evaluate soil properties of an Alfisol and soybean yield under different management systems for no-tillage annual crops, no-tillage with chiseling and no-tillage crop rotation. The 11-year experiment was initiated in the 1998/99 growing season, on 100*30 m plots (11% slope). Soil samples (5 per management system) were systematically collected (0-25 cm layer) in the summer growing season, to quantify soil organic matter, bulk density, macroporosity and flocculation, as well as soybean yield. The highest values for soil bulk density and organic matter content and the lowest for macroporosity were observed in the no-till system alone, whereas in the no-till system with quarterly chiseling the values for organic matter content were lowest, and no-tillage crop rotation resulted in the highest values for organic matter and macroporosity, and the lowest for soil bulk density. The average soybean yield was highest under no-till and trimestrial chiseling or crop rotation, and lowest for no-tillage annual crops no-tillage annual crops alone.
  • Authors:
    • Ugarte, D. G. de la T.
    • English, B. C.
    • Roberts, R. K.
    • Larson, J. A.
    • Toliver, D. K.
    • West, T. O.
  • Source: Agronomy Journal
  • Volume: 104
  • Issue: 2
  • Year: 2012
  • Summary: This research evaluated differences in yields and associated downside risk from using no-till and tillage practices. Yields from 442 paired tillage experiments across the United States were evaluated with respect to six crops and environmental factors including geographic location, annual precipitation, soil texture, and time since conversion from tillage to no-till. Results indicated that mean yields for sorghum [ Sorghum bicolor (L.) Moench] and wheat ( Triticum aestivum L.) with no-till were greater than with tillage. In addition, no-till tended to produce similar or greater mean yields than tillage for crops grown on loamy soils in the Southern Seaboard and Mississippi Portal regions. A warmer and more humid climate and warmer soils in these regions relative to the Heartland, Basin and Range, and Fruitful Rim regions appear to favor no-till on loamy soils. With the exception of corn ( Zea mays L.) and cotton ( Gossypium hirsutum L.) in the Southern Seaboard region, no-till performed poorly on sandy soils. Crops grown in the Southern Seaboard were less likely to have lower no-till yields than tillage yields on loamy soils and thus had lower downside yield risk than other farm resource regions. Consistent with mean yield results, soybean [ Glycine max (L.) Merr.] and wheat grown on sandy soils in the Southern Seaboard region using no-till had larger downside yield risks than when produced with no-till on loamy soils. The key findings of this study support the hypothesis that soil and climate factors impact no-till yields relative to tillage yields and may be an important factor influencing risk and expected return and the adoption of the practice by farmers.
  • Authors:
    • Rasaily, R. G.
    • Lu, C.
    • Li, H.
    • He, J.
    • Wang, Q.
    • Su, Y.
  • Source: Transactions of the Chinese Society of Agricultural Engineering
  • Volume: 28
  • Issue: 1
  • Year: 2012
  • Summary: In order to solve the problems of residue blocking and difficulty to open the furrow of no-till wheat planter in heavy corn residue cover fields in annual double cropping areas of the North China, a telescopic lever furrowing and anti-blocking unit was designed for no-till planter. Its key parameters were determined based on a band between orthogonal test and the structure analysis, and a telescopic lever furrowing and anti-blocking unit was used to conduct the field experiment. The field experiment showed that the telescopic lever furrowing and anti-blocking unit could solve the problem of straw blocking effectively and improve the seeding quality. Compared with the strip rotary-tilling anti-blocking unit, the telescopic lever furrowing and anti-blocking unit could reduce topsoil disturbance quantity by 21.5%; fuel consumption per unit area was reduced by 23.65% when the depth of furrow opening was 10 cm, which could reduce power consumption of tractor. Above all, the telescopic lever furrowing and anti-blocking unit has important value in extending no-tillage planter.