- Authors:
- Perim, L.
- Castro, G.
- Crusciol, C.
- Marques, R.
- Source: REVISTA BRASILEIRA DE CIENCIA DO SOLO
- Volume: 35
- Issue: 2
- Year: 2011
- Summary: Lime and gypsum influence nutrient availability and uptake, as well as the content of organic acids in the aerial plant parts. These changes, quantified by plant analysis of soluble nutrients, may potentiate the effect of soil amendment, ensuring the sustainability of the no-tillage system. In this sense the effect of lime and gypsum surface application on the content of water-soluble nutrients in peanut and oat residues was evaluated. The experiment was conducted on an Oxisol in Botucatu (SP) in the growing seasons 2004/2005 and 2005/2006. It was arranged in a randomized block design in split plots with four replications, where lime rates represented the plots and presence or absence of gypsum application the subplots. Peanut was grown in summer and white oat in the winter in the entire experimental area. Gypsum applied to peanut increased soluble Ca only in the first season, due to the short period between product application and determination of soluble nutrient contents in the plant extract. Liming of peanut and oat increased soluble Ca, Mg, K contents, did not alter Cu content and reduced Zn, Mn and Fe contents in both years of cultivation. Gypsum on the other hand reduced the electrical conductivity of peanut (2004/2005 and 2005/2006) and white oat (2004/2005).
- Authors:
- Silva Junior, A.
- Alves, M.
- Muraishi, C.
- Souza, Z.
- Source: ACTA SCIENTIARUM-AGRONOMY
- Volume: 33
- Issue: 3
- Year: 2011
- Summary: This study was conducted at the Experimental Station belonging to UNESP Engineering University, Ilha Solteira Campus, based in Selviria, Mato Grosso do Sul State, Brazil, with the aim of evaluating chemical alterations in an Oxisol after being managed for two years with organic and/or chemical fertilization and different tillage systems during the agricultural years of 2004/2005 and 2005/2006. The treatments were: conventional-tillage; chisel tillage and no-tillage; the fertilization treatments were: control (no fertilization); chemical fertilization (300 kg ha -1 from the 20-00-20); organic fertilization (cattle manure - 20 Mg ha -1); organic+1/2 the recommended chemical fertilization for the used crop; 20 and 30 Mg ha -1 of sewage sludge. Soybean was used in the first year and sorghum in the next year, evaluating the soil chemical attributes in four layers. The soil chemical attributes were changed in the first year; the organic fertilization, sewage sludge and organic+chemical fertilization were efficient to change the chemical attributes; the sewage sludge was more efficient in soil P recuperation and, the no-tillage system contributed to soil K increase.
- Authors:
- Bergamaschine, A.
- Ulian, N.
- Araujo, F.
- Andreotti, M.
- Azenha, M.
- Pariz, C.
- Source: PESQUISA AGROPECUARIA BRASILEIRA
- Volume: 46
- Issue: 10
- Year: 2011
- Summary: The objective of this work was to evaluate the dry matter yield and chemical composition of forage in crop-livestock integration, according to different sowing dates. A randomized experimental block design in a 4*3 factorial scheme was used, with four forage plants (palisadegrass, Urochloa brizantha; fox millet, Setaria italica; pearl millet, Pennisetum glaucum; and sorghum, Sorghum bicolor) sowed on three dates, in two season (winter/spring and summer/autumn), in succession to soybean. The pearl millet and sorghum produced the highest amount of dry matter in all sowing dates, at both growing seasons and, contrary to palisadegrass and fox millet, it did not reduce the amount of total digestible nutrients. Crude protein levels decreased with the advancement of sowing dates in winter/spring and increased in summer/autumn, except for palisadegrass and pearl millet. Sorghum showed the lowest concentrations of neutral detergent fiber in the second and third sowing dates in winter/spring, and in the first sowing date in summer/autumn. In the second and third sowing dates in winter/spring, sorghum showed the lowest content of acid detergent fiber. In relation to the cell wall components, only the hemicellulose contents did not change in the forages due to sowing dates, at both seasons.
- Authors:
- Amarante, I.
- Machado, J.
- Fontaneli, R.
- Santos, H.
- Source: Pesquisa Agropecuaria Gaucha
- Volume: 17
- Issue: 1
- Year: 2011
- Summary: The effects of soil management systems and crop rotation on sorghum yield characteristics agronomic were evaluated during the period 2003/04 to 2010/11 at EmbrapaTrigo, Passo Fundo, RS, Brazil. Four soil management systems: (1) no tillage, (2) minimum tillage, conventional tillage using a disk plow and a disk harrow, and (4) conventional using a moldboard and a disk harrow; and three crop rotation system I (wheat/soybean), system II (wheat/soybean and common vetch/sorghum), and system III (wheat/soybean, white oats/soybean and common vetch/sorghum) were compared. An experimental design of blocks at random, with split-plots and three replications, was used. The main plot was formed by the soil management systems, while the split-plot constituted of the crop rotation systems. Minimum tillage and no-tillage presented higher yield of sorghum, while conventional tillage using a moldboard plow remained in intermediate position and tillage using disk plow the lowest yield of sorghum. The yield of sorghum grown after common vetch in system II was higher than yield obtained for sorghum after common vetch in system I. No significant differences were observed in sorghum characteristics agronomic as a result of soil management and crop rotation systems.
- Authors:
- Source: Revista Brasileira de Milho e Sorgo
- Volume: 10
- Issue: 2
- Year: 2011
- Summary: Pest species that are enhanced by cover crops used in no-tillage farming can cause damages to subsequent crops of economic importance planted into cover crops stubble. In the 2006/2007 growing season, in Dourados, MS, Brazil, a study was carried out to assess the arthropod fauna in three soybean no-tillage systems: unseeded vegetation-soybean, pearl millet-soybean and sorghum-soybean. During the soybean pre-planting season and the early soybean season, the incidence of pests and natural enemies was assessed in 1 m 2 of the cover crops and later on their respective stubble with soybean seedlings in development using a wood made frame square ("wood square" sampling method). The most abundant species at the soybean pre-planting season were caterpillars of Mythimna ( Pseudaletia) sequax and Mocis latipes (Lepidoptera: Noctuidae), and adults and nymphs of the predator Doru luteipes (Dermaptera: Forficulidae), showing a significant population increase on the pearl millet green cover crop. After the cover crops desiccation the incidence of Lagria villosa (Coleoptera: Lagriidae) species was significant on sorghum and pearl millet stubble and the genus Agrotis sp. (Lepidoptera: Noctuidae) on sorghum cover. Thus, the bioecology of pests and natural enemies associated with pearl millet as cover crop might be considered on the development of Integrated Pest Management (IPM) programs in conservation farming systems.
- Authors:
- Costa, M.
- Castoldi, G.
- Pivetta, L.
- Steiner, F.
- Costa, L.
- Source: Revista Brasileira de Ciencias Agrarias
- Volume: 6
- Issue: 3
- Year: 2011
- Summary: The organic carbon is a major component of the soil organic matter, and its stock is influenced by the type of management system used. This study aimed to evaluate the effect of two cropping systems, with and without cover crop rotation, associated to three fertilization sources (mineral, organic and mineral+organic) in the organic and residual carbon contents of an Oxisol, in no-tillage system. Soil samples were collected at 0.0-0.10, 0.10-0.20 and 0.20-0.40 m depth in the first, second and third years of the experiment, installed in 2006. The crops sequence in the rotation system with cover crops was oat+vetch+turnip/corn/wheat/mucuna+brachiaria+crotalaria/corn/soybean, and in the following system it was wheat/corn/wheat/soybean/corn/soybean. The organic and mineral+organic fertilizers consisted in the sole application of organic fertilizers and combined with mineral fertilizer. The organic and residual carbon contents were not affected by the different cropping systems. The organic and mineral+organic fertilizers promoted increases in the organic and residual carbon contents. The system of crop succession fertilized with mineral fertilizer resulted in higher losses of soil carbon.
- Authors:
- Machado, V.
- Lopes, J.
- Souza, R.
- Souza, C.
- Teixeira, C.
- Source: Informe Agropecuario
- Volume: 32
- Issue: 260
- Year: 2011
- Summary: The successful implementation and establishment of the no-tillage (NT) system is directly related to the maintenance of straw on the soil surface. The system of crop rotation also contributes to the success of NT. In the Cerrado (Minas Gerais, Brazil), the high temperature and rainfall mainly during the first six months accelerate straw decomposition and hinder the cultivation of crops during the winter. This paper presents various crop management options to promote the success of NT in the Cerrado region. Most notable is the oversowing of millet in soyabean and Santa Fe system, which involves a mixture of grasses and perennial crops, such as sorghum, millet and maize.
- Authors:
- Gradin, B.
- Holm, F.
- Stevenson, F.
- Leeson, J.
- Legere, A.
- Thomas, A.
- Source: Weed Research
- Volume: 51
- Issue: 1
- Year: 2011
- Summary: Contrasting approaches to integrated weed management (IWM) for prairie cropping systems were evaluated by measuring weed response to six IWM systems in a wheat-oilseed rape-barley-pea rotation at Saskatoon and Watrous, Saskatchewan, Canada. The six IWM systems (high herbicide/zero tillage; medium herbicide/zero tillage; low herbicide/zero tillage; low herbicide/low tillage; medium herbicide/medium tillage; no herbicide/high tillage) included various combinations of seeding rate and date, herbicide timing and rate, and tillage operations, in order to achieve similar weed management levels. Changes in weed communities were assessed over 4 years by monitoring species composition and abundance at various times during the growth season. Principal response curves indicated a gradual increase in Thlaspi arvense, Chenopodium album, Amaranthus retroflexus and Fallopia convolvulus in the no herbicide/high tillage system. Winter and early spring annuals and perennials increased in most systems, but particularly in the low herbicide/zero tillage and medium herbicide/zero tillage systems. Although five of the six IWM systems provided similar results, changes in weed communities would suggest that operations could be revised to improve the overall management of certain weed species and reduce seed return in the no herbicide/high tillage system and in systems with low herbicide inputs and zero tillage. This study confirms the potential of contrasting IWM systems under the challenging environmental conditions of the Canadian Prairies.
- Authors:
- Source: BULGARIAN JOURNAL OF AGRICULTURAL SCIENCE
- Volume: 17
- Issue: 4
- Year: 2011
- Summary: The soil surface CO 2 flux is the second largest flux in the terrestrial carbon budget after photosynthesis. Plant root and microbial respiration produce CO 2 in soils, which are important components of the global C cycle. This study determined the amount of CO 2 released during spring wheat ( Triticum aestivum L.) growth under no-till (NT) and conventional tillage (CT) systems. This experiment was conducted at Kansas State University North Agronomy Farm, Manhattan, KS, on a Kennebec silt loam. This study site was previously under dry land continuous corn production with NT and CT for more than 10 years. Spring wheat ( Triticum aestivum L.) was planted with two tillage systems (NT and CT) as four replicates in March. Surface CO 2 flux was measured weekly during plant growth. Soil water content at the surface (5 cm) tended to be greater in NT and decreased from planting to harvest. Soil microbial activity at the surface was usually higher in NT and decreased from planting to harvest, while activity was constant in the deeper depths. The higher microbial activity at the surface of NT occurred after 60 days of planting where soil water content was the most limiting factor on microbial activity. Soil CO 2 flux varied in response to changes in soil water content and the variation and magnitude of the increase was greater at higher soil water contents. Conventional tillage released 20% more CO 2 to the atmosphere compare to NT after 10 years in the North American Great Plains Regions.
- Authors:
- Olson, B. L.
- Schlegel, A. J.
- Holman, J. D.
- Maxwell, S. R.
- Source: Crop Management
- Issue: June
- Year: 2011
- Summary: A common crop rotation in the west-central Great Plains is no-till winter wheat-corn-fallow. Because most of the corn produced is herbicide-tolerant, volunteer corn in fallow is not controlled with glyphosate. This study evaluated the impact of volunteer corn on soil moisture storage in fallow and the succeeding winter wheat crop across three locations in western Kansas from 2008 to 2010. Volunteer corn reduced available soil water at wheat planting in 8 out of 9 site years. On average, available soil water was reduced by 1 inch for each 2,500 volunteer corn plants per acre. Volunteer corn water use reduced wheat tillers in half of the site years. Similarly, volunteer corn reduced wheat yields in half of the site years, and yields fell 1 bu/acre for every 500 volunteer corn plants per acre. When wheat yields were above 70 bu/acre or below 35 bu/acre, other factors affected wheat yield more than the preceding volunteer corn population or available soil water at wheat planting.
