• Authors:
    • Buzetti, S.
    • Bergamaschine, A. F.
    • Andreotti, M.
    • Pariz, C. M.
    • Costa, N. R.
    • Cavallini, M. C.
  • Source: Archivos de Zootecnia
  • Volume: 60
  • Issue: 232(1)
  • Year: 2011
  • Summary: We evaluated the effect of fertilization with 0, 50, 100 and 200 kg/ha of N, applied in each four growth intervals in the winter/spring season on dry matter yield in 30 days (DMY), leaf chlorophyll index (LCI) and total digestible nutrients (TDN), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin contents, and correlation equations of LCI with DMY and CP content in the marandu and ruziziensis grasses after intercrop arrangements with corn in Red Latosol (Oxisol) under irrigation. The major DMY occurred with photoperiod increasing, however, there were different responses to this attribute over of growth intervals, between and among the grasses with the N fertilization. In irrigated crop-livestock integration under savannah soil is technicality viable the cultivation of marandu and ruziziensis grasses, established by intercrop with corn at sowing or at the N fertilization. As even, in the N fertilization absence, produced satisfactory amounts of forage, with 1733 kg/ha (DMY), at the time of greatest scarcity of roughage to animals (winter/spring season). However, after the corn harvest, the N fertilization increase the DMY and improves the chemical composition, increasing the LCI, and CP and TDN contents, and decreasing NDF and ADF contents in the winter/spring season. The best correlation equations in function of LCI were logatithmica for DMY and potential for CP of the marandu grass and potential for both attributes of the ruziziensis grass.
  • Authors:
    • Rosolem, C. A.
    • dos Santos, G. P.
    • Castoldi, G.
    • Pivetta, L. A.
  • Source: Pesquisa Agropecuária Brasileira
  • Volume: 46
  • Issue: 11
  • Year: 2011
  • Summary: The objective of this work was to assess winter and spring crop effects on soybean root system growth, and on yield, and to compare a direct method (soil core sampling) with an indirect method (with rubidium) in evaluating the root system. The experimental design was a randomized complete block design, in a split-plot arrangement, with four replicates. Plots consisted of the winter crops, triticale (X Triticosecale) and sunflower (Helianthus annuus), and subplots of the spring crops, pearl millet (Pennisetum glaucum), forage sorghum (Sorghum bicolor) and sunn hemp (Crotalaria juncea), besides chisel tillage in 2003 and 2009. Soybean (Glycine max) was grown in the summer, and its root system was evaluated by physical sampling of the roots and by root activity assessment using rubidium. Changes in the architecture or in the activity of soybean roots did not affect yield. The distribution and activity of soybean roots were not significantly affected by the winter cover crops, but root growth was favored after millet and sorghum were grown in the spring. The direct measurement of the soybean root system with an auger has low correlation with root activity.
  • Authors:
    • Passos, A. M. A. dos
    • Albuquerque, A. de
    • Resende, P. M. de
    • Baliza, D. P.
    • Reis, W. P.
    • Botrel, E. P.
  • Source: Revista de Agricultura
  • Volume: 86
  • Issue: 1
  • Year: 2011
  • Summary: The objective of this work was to compare the potential of the irrigated wheat under no tillage and conventional cropping systems, as well as to evaluate the performance of fifteen wheat cultivars in the two cropping systems, in succession to soybean crop, in the South of Minas Gerais. The experiment was carried out in the Federal University of Lavras (UFLA), in Lavras, MG, in the years of 2006/07 and 2007/08, in a split-block-designed scheme in a randomized complete block design, with three replications. The cropping systems (conventional and no-tillage) were installed in the rows and, in the columns, the fifteen wheat cultivars were distributed. The wheat yield and others agronomic characteristics were evaluated. The no-tillage provided an average increase of 25% in the organic matter levels in the topsoil layer in relation to previous levels and to conventional cropping system. The cultivars tested, independent of the agricultural year, significantly altered the grain yields and the agronomic characteristics. The high yield presented by the cultivars evaluated in this study indicates the high potential of the irrigated wheat cropped in succession to soybean crops, under similar climatic and soil conditions used in this study.
  • Authors:
    • Mauli, M. M.
    • de Lima, G. P.
    • Pereira Nóbrega, L. H.
    • Rosa, D. M.
  • Source: Semina: Ciências Agrárias (Londrina)
  • Volume: 32
  • Issue: 4
  • Year: 2011
  • Summary: The no-tillage system management is considered as an agricultural system very close to sustainability, since it causes less impact to the environment. The crops rotation, when well managed, includes the use of green manure; and leguminous are included in this system as they bring a number of benefits. This context, the study aimed tested leguminous as cover plants on soil with a no-tillage system regarding the growth, yield and maize seeds quality. This decision-making looks for alternatives that contribute for the agroecosystem sustainability, since they allow rational adoption of green manure in production units. The experiment was carried out in the field with leguminous species dwarf mucuna beans, dwarf pigeon pea and stylosanthes, sown in October 2007, in 4 x 5 m plots, with five replications. At 90 days after the cover crops sowing, the leguminous plants were grazed and corn plants were sown 15 days after grazing on waste. The plants heights were determined during the culture development. At the laboratory, after harvest, the productivity and physiological quality of seeds were determined. The experimental design was completely randomized and the averages were compared by the Scott-Knott test at 5% of significance. At 60 days after the maize crop sowing, the treatments with dwarf mucuna beans and dwarf pigeon pea showed higher heights. The other analyzed parameters did not differ among themselves, showing that the treatments not interfere on the maize crop. Actually, it is an alternative to the integrated management of species concerning the summer green manure and crop rotation in no-tillage system.
  • Authors:
    • Cella, A. J. S.
    • Ferraz, E. de C.
    • Barros, H. B.
    • Santos, E. R. dos
    • Capone, A.
    • Santos, A. F. dos
    • Fidelis, R. R.
  • Source: Revista Ceres
  • Volume: 58
  • Issue: 6
  • Year: 2011
  • Summary: The genetic diversity is one of the most important parameters evaluated by plant breeders in the early stages of a genetic improvement program. The objective of this paper was to evaluate the genetic divergence by means of multivariate techniques, among 48 soybean genotypes grown in irrigated lowland in the State of Tocantins, in order to select parents of hybrids for the production of oil and meal, as well as varieties of the panel, intended for human consumption. The experiment was conducted in the county Formoso do Araguaia - Tocantins, Brazil, in the cultivation of irrigated lowland, in the inter-cropping 2010. The experimental design was a randomized block with four replications. There was observed variability among the genotype tested. The Tocher's method, UPGMA and Canonic Variables agreed among themselves, and found four distinct groups. The following hybrids are promising for the production of soybean oil and meal for the M-Soy 8766, M-Soy 9144, A-7002 and M-soy 9056 with Amaralina RR crosses between and M-Soy 8766, M-Soy 9144 and Amaralina RR with BRSMG 790A, BRS 257, BRS 216 and BRS 213, are listed in order especially soybeans for human consumption.
  • Authors:
    • Sediyama, G. C.
    • Moura, M. S. B. de
    • Souza, L. S. B. de
    • Silva, T. G. F. da
  • Source: Bragantia
  • Volume: 70
  • Issue: 3
  • Year: 2011
  • Summary: This study aimed to analyze the productivity, the water use efficiency, and the economical viability for corn and cowpea crops on single and intercropping systems in the Brazilian semiarid region. The experiment was carried out at Petrolina, State of Pernambuco. The crops, in different planting systems (single and intercropping), underwent the five blades of irrigation, applied at the flowering stage of cowpea to 40 days after sowing. Combining the settings of cultivation system and the different depths of irrigation, crops of maize and cowpea were subjected to 15 different treatments. To evaluate the performance of crops in the different treatments indicators that consider the production response of crops and the performance of the application of water in the production system were used. The grain yield responses of maize and cowpea to the soil water content were reduced in intercropped plantations, in relation to single cropping. Even so, in economic terms, the adoption of maize-cowpea proved to be more advantageous in all treatments.
  • Authors:
    • Pulrolnik, K.
    • Marchão, R. L.
    • Guimarães Junior, R.
    • Motta Macedo, M. C.
    • Martha Junior, G. B.
    • Vilela, L.
    • Maciel, G. A.
  • Source: Pesquisa Agropecuária Brasileira
  • Volume: 46
  • Issue: 10
  • Year: 2011
  • Summary: The objective of this work was to analyze the benefits and the potential prospects of integrated crop-livestock systems in the process of crop and pasture intensification in the Cerrado, and to point out the main information gaps about the system. The main benefits of crop-livestock integration are: improved chemical, physical and biological properties of the soil; reduction of diseases, pests and weed outbreaks occurrence; higher crop and animal productivity; and risk reduction due to diversification of activities. However, the adoption of the crop-livestock system is still low, probably due to the greater complexity of the system. Concentrating efforts on the factors that limit the system's adoption is strategic for new studies. The search for better soil cover for the no tillage system, through forage grasses, can boost the adoption of integrated crop-livestock in the Cerrado. It is expected that the adoption of integrated crop-livestock systems improve the socioeconomic and environmental sustainability of the farm and of its region of influence.
  • Authors:
    • Almeida, N. A.
    • Oliveira, I. R. de
    • Carvalho, L. M. de
    • Andrade, K. R.
  • Source: Acta Horticulturae
  • Issue: 925
  • Year: 2011
  • Summary: Fennel ( Foeniculum vulgare Miller), Apiaceae, a spice and medicinal plant from the Mediterranean region, is grown by family farmers without irrigation and under high temperature conditions of the Brazilian northeast. In this study, a field experiment was done in the semi-arid region of Sergipe state, Brazil, to evaluate the performance of fennel-bean intercrop under organic management, using a completely randomized block design with six replications and four treatments (fennel monocrop and fennel intercropped (additive model)) with two cultivars of beans ( Phaseolus vulgaris) and one cultivar of cowpea ( Vigna unguiculata). Fennel plants were obtained from seeds and transplanted into the field at the beginning of the rainy season in June, while seeds of the beans and cowpea were being sown. Umbels of the fennel were harvested in January, 210 days after transplanting the fennel into the field. The fresh and dry mass of umbels, absolute and relative yield, land equivalent ratio (LER) and essential oil content were improved under the intercrop with cowpea and one cultivar of bean. No significant differences were detected on height and canopy areas among treatments, but any decrease in yield of fennel plants associated with intercrops with cowpea or bean were small. The intercrops studies confirmed the viability of intercropping fennel with cowpeas and beans.
  • Authors:
    • Negrisoli, E.
    • Crusciol, C. A. C.
    • Castro, G. S. A.
    • Perim, L.
  • Source: Planta Daninha
  • Volume: 29
  • Year: 2011
  • Summary: Tillage and other agricultural production systems can contribute to weed suppression. Thus, the objective of this study was to evaluate weed control using different grain production systems. The treatments were: I. "Harvest-fallow" System-soybean/fallow/corn/fallow/rice/fallow/soybean; II. "Harvest-green manure" System-soybean/millet/maize/pigeon pea/rice/Crotalaria/soybean; III. "Harvest-out of season" System-soy/white oats/corn/dry bean/rice/castor oil/soybean; and IV "Harvest-fodder" System-brachiaria + soy/corn + brachiaria/brachiaria + rice/soybeans. A weed survey was carried out in November 2009, after three growing seasons. A 0.3 x 0.3 m frame was randomly launched four times within each plot. The plants were identified, and the total number of weeds, dry weight, and control percentage of the species were determined according to the production system. The phytosociological analysis of the weed community was also conducted. The systems Harvest-green manure; Harvest-out of season and Harvest-fodder presented a good weed control when compared to the Harvest-fallow system. Therefore, the presence of some type of soil cover is important to maintain favorable soil characteristics and good weed control.
  • Authors:
    • Giuffre, L.
    • Giardina, E. B.
    • Ciarlo, E. A.
    • Garcia Torres, T. P.
  • Source: REVISTA FACULTAD DE AGRONOMÍA Universidad de Buenos Aires
  • Volume: 31
  • Issue: 1/2
  • Year: 2011
  • Summary: The dynamics of nutrient availability and other soil properties can be strongly altered by agricultural practices like intercropping. A test was made on an agricultural soil with the following treatments: (i) sole cropped soybean, (II) sole cropped maize and (III) intercropped corn-soybean in a 1:2 ratio. Surface soil samplings were made in two moments: the first one (F1) was made with corn at V5 and soybean just emerged; the second one (F2) with corn crop at R1 and soybean crop at V7-R1, both at two distances of the furrows: 5 and 19 cm. Oxidizable C contents were always maximum at the treatments including corn cropping. At both dates, extractable P was maximum at sole corn and minimum at sole soybean crop, which can be attributed to a strong uptake by the leguminous plant. In the first measurement date, at 5 cm of the corresponding furrow, nitrate availability was significantly greater at the soybean treatments with respect to treatments including corn, whereas in the second date, nitrate availability was minimum at sole soybean, which seems to be due to differences in crops development. Finally, the practice of intercropping, within the frame of this test, did not prove to be a viable alternative to limit the existence of high nitrate levels.