Instituto Agronomico do Parana IAPAR
Instituto Agronomico do Parana IAPAR
Petean L.P.,State University of Maringá |
Tormena C.A.,UEM |
Alves S.J.,Instituto Agronomico do Parana IAPAR
Revista Brasileira de Ciencia do Solo | Year: 2010
The least limiting water range (LLWR) is considered a modern indicator of soil physical quality for plant growth. The aim of this study was to determine the LLWR for assessing the soil physical quality of a dystroferric Red Latosol (Oxisol) under no-tillage in a crop-livestock integration system. In the crop-livestock integration system of the study area, soybean was planted in the summer and oat (Avena strigosa Schreb) plus ryegrass (Lolium multiflorum Lam) in the winter with different pasture heights during grazing: 7, 14, 21, and 28 cm, and an ungrazed control. Undisturbed soils samples were taken from the layers 0-7.5 and 7.5-15 cm, in which the soil bulk density (Bd), soil water retention and soil resistance to penetration curves were determined, to then calculate the LLWR. The critical soil bulk density (Bdc) was determined for LLWR=0. Regardless of the treatments, it was found that an increase of the soil bulk density requires an increase of soil water contents to maintain soil penetration resistance below 2.5 MPa and a decrease in soil water to ensure adequate soil aeration, mainly in the 0-7.5 cm layer. In the treatments with grazing heights of 21 and 28 cm, the magnitude of LLWR was greater than in the control, suggesting that crop-livestock integration creates a positive soil physical environment, provided that an appropriate stocking is maintained to prevent overgrazing. In the 7 cm treatment, the soil physical degradation was very high in the 0-7.5 cm layer, and certainly predisposes the crops to stress resistance to soil drying and to reduced aeration under prolonged conditions of high soil moisture. A progressive reduction in the proportion of samples with greater bulk density values than the critical density of the 7 cm treatment toward the control was verified, indicating that the treatment effect of excessive animal trampling resulted in a loss of soil physical quality in the 0-7.5 cm soil layer. The grazing height of oat and ryegrass pasture should be maintained above 21 cm to ensure adequate physical soil quality in the 0-7.5 cm soil layer.
Ricce W.S.,Instituto Agronomico do Parana IAPAR |
Caramori P.H.,Instituto Agronomico do Parana IAPAR |
Roberto S.R.,State University Londrina
Bragantia | Year: 2013
Grapes have the potential for continuous production after a short rest period between seasons, but climate risks may limit this practice. The objective of this study was to evaluate the climatic potential for two harvests of grapes per year and to estimate the severity of downy mildew, according to different pruning times and thermal requirements (degree-days) for grape genotypes (Vitis spp.), in the State of Parana, Brazil. Frost risk, normal climatological water balance and potential severity of downy mildew were evaluated using data from 21 meteorological stations of the Instituto Agronômico do Paraná. The occurrence of frost limits the growing season of grapevines in the central, south and east regions of the state. The water excess is observed throughout the state. Genotypes with requirements from 1,800°C day between pruning and harvesting can only be cultivated in double annual crop in the warmer areas of the State. It is not possible to obtain two harvests per year when using grapevine genotypes that require more than 2,000°C day. In colder areas, only genotypes with requirements between 1,000 and 1,200°C day may be used. Due to the potential severity of downy mildew in the State, American grapes are indicated for the center, south and east areas, while European grapes are indicated for the southwest, west, north and northwest areas. The grape cultivation in those areas does not discard the need of disease chemical control during the most susceptible phenological phases.
dos Santos T.B.,Instituto Agronomico do Parana IAPAR |
Budzinski I.G.F.,Instituto Agronomico do Parana IAPAR |
Marur C.J.,Instituto Agronomico do Parana IAPAR |
Petkowicz C.L.O.,Federal University of Paraná |
And 2 more authors.
Plant Physiology and Biochemistry | Year: 2011
Galactinol synthase (EC 18.104.22.168; GolS) catalyzes the first step in the synthesis of raffinose family oligosaccharides (RFOs). Their accumulation in response to abiotic stresses implies a role for RFOs in stress adaptation. In this study, the expression patterns of three isoforms of galactinol synthase (CaGolS1-2-3) from Coffea arabica were evaluated in response to water deficit, salinity and heat stress. All CaGolS isoforms were highly expressed in leaves while little to no expression were detected in flower buds, flowers, plagiotropic shoots, roots, endosperm and pericarp of mature fruits. Transcriptional analysis indicated that the genes were differentially regulated under water deficit, high salt and heat stress. CaGolS1 isoform is constitutively expressed in plants under normal growth conditions and was the most responsive during all stress treatments. CaGolS2 is unique among the three isoforms in that it was detected only under severe water deficit and salt stresses. CaGolS3 was primarily expressed under moderate and severe drought. This isoform was induced only at the third day of heat and under high salt stress. The increase in GolS transcription was not reflected into the amount of galactinol in coffee leaves, as specific glycosyltransferases most likely used galactinol to transfer galactose units to higher homologous oligosaccharides, as suggested by the increase of raffinose and stachyose during the stresses. © 2011 Elsevier Masson SAS.
Minuzzi R.B.,Federal University of Santa Catarina |
Caramori P.H.,Instituto Agronomico do Parana IAPAR |
Borrozino E.,Instituto Agronomico do Parana IAPAR
Bragantia | Year: 2011
This study aimed to analyze the variability of seasonal and annual maximum and minimum air temperatures in the State of Paraná, southern Brazil. The regression analysis and Kendall test were used to test the trend of mean maximum and minimum temperatures, number of days with records of temperature below 3 °C, extreme events and absolute daily maximum and minimum temperatures on seasonal scales (summer, autumn, winter and spring) and annual. The points of discontinuity obtained by the Standard Normal Homogeneity Test showed more significant results for the annual maximum temperature in the autumn. For this meteorological variable points were obtained predominantly in the early 2000s. The annual maximum temperature and mainly minimum temperature at all time scales tended to increase. This increase was relatively larger in the minimum temperature, which suggests a decrease in the thermal amplitude in Paraná. The values of the extreme daily minimum temperature are being higher, but less frequent. On the other hand, the maximum temperatures have been more intense and frequent, especially in spring.
Borsato L.C.,Instituto Agronomico do Parana IAPAR |
di Piero R.M.,Federal University of Santa Catarina |
Stadnik M.J.,Federal University of Santa Catarina
Tropical Plant Pathology | Year: 2010
The aim of this work was to evaluate the potential of algal polysaccharide ulvan to induce resistance to rust and to study defense mechanisms triggered by it in bean cultivars showing different levels of resistance. Bean cultivars of carioca group, i.e., BR IPA - 11 Brigida (resistant), Perola (moderately susceptible) and IPR Juriti (susceptible), were sprayed with ulvan (10 mg/ mL) or distilled water (control) at 6 and 3 days before inoculation with Uromyces appendiculatus. Ulvan reduced the diameter of pustules on the three cultivars and led to an increase in the activity of glucanases only in cv. Perola, 48 h after inoculation. The polysaccharide did not inhibit the germination of the fungus in leaf discs and did not alter the activity of peroxidases. Comparing the cultivars, Brigida exhibited a significantly lower number and diameter of pustules, but allowed the highest germination of uredospores on the leaf surface. The activities of peroxidases and glucanases were lower in this cultivar compared to the susceptible one (Juriti). Based on the results, we discuss the role of some resistance mechanisms in both basal and ulvan-induced resistance of bean towards the rust fungus.
Ribeiro M.D.F.D.S.,Instituto AgronOmico do Parana IAPAR |
Raiher A.P.,State University of Ponta Grossa
Energy Policy | Year: 2013
The State of Paraná contributes significantly for the Brazilian production of sugar cane, ethanol, soybeans and pigs. In addition to the current production of ethanol, the State has a huge potential for electricity, biodiesel and biogas production. This paper presents an overview of the current situation regarding energy generation from the agricultural sector in the State, an assessment of the potentialities of energy generation from sugar cane residues and pig agricultural chains, as well as an analysis of the socioeconomic factors underlying the availability of feedstock for biodiesel production. This study has shown that it is possible to expand the energy supply in the State using residual biomass from the sugar cane and pig production. On the other side, the biodiesel production increase in the State will depend on the expansion in the consumption of products that use the cake as raw material; the increase in the feedstock availability other than canola, castor beans and sunflower; the increase of the number of family farmers as feedstock providers, so as to ensure access for biodiesel producers to the Social Fuel Stamp. © 2013 Elsevier Ltd.
Araujo-Junior C.F.,Instituto Agronomico do Parana IAPAR |
Dias Junior M.S.,Brazilian National Council for Scientific and Technological Development |
Guimaraes P.T.G.,Federal University of Lavras |
Alcantara E.N.,Federal University of Lavras
Revista Brasileira de Ciencia do Solo | Year: 2011
Different weed managements in coffee have led to structural changes, affecting the soil physical quality. Therefore, information on the load bearing capacity of the soil under different weed managements is essential to establish a sustainable soil management under coffee. The objectives of this study were to: (a) assess the influence of different weed managements over three decades on the load bearing capacity of a Dystroferric Red Latosol (LVdf) cultivated with coffee on the Epamig Farm in São Sebastião do Paraíso, Minas Gerais State (Latitude de 20 ° 55 ' 00 S and Longitude 47 ° 07 ' 10 W); (b) determine the maximum stress (σmax) exerted by a tractor; (c) establish the critical water content (θcrítica) for tractor traffic. The following weed managements were assessed: no weeding (SCAP); hand weeding (CAPM); post-emergence herbicide (HPOS); mowing (ROÇA); rotary tiller (ENRT); tandem disk harrow (GRAD) and pre-emergence herbicide (HPRE). In each management system 15 undisturbed soil samples were collected randomly in the coffee inter-rows in the layers 0-3, 10-13 and 25-28 cm, totaling 315 soil samples. Additionally, 15 samples per layer were collected in a native forest (MATA). The equipment used in coffee management was coupled to a Valmet® model 68 tractor for coffee. To determine θcrítica for tractor traffic, only the stress was considered that did not exceed the internal strength of the soil expressed as precompression stress. The undisturbed soil samples were used to determine precompression stress (σp) at different volumetric water contents (θ) and then bulk density (Bd). Disturbed samples were used to analyze particle size distribution, organic carbon (OC) and total oxides. Load bearing capacity (LBC) between precompression stress and volumetric water content was calculated (σp = 10(a+bθ)) to assess the possible effects of weed management systems on soil structure. The maximum stress caused by the Valmet® tractor (inflation pressure of the front tires 6-16 of 172 kPa) was 220 kPa. The lowest critical water content was 0.27 cm3 cm-3 for the Dystroferric Red Latosol under no weeding in the 0-3 cm layer and the highest 0.48 cm3 cm-3 for the soil managed with pre-emergence herbicide in the 0-3 cm layer. The weed management with disk harrow and pre-emergence herbicide led to crusting on the soil surface and increased bulk density and precompression stress. The load bearing capacity of the soil under native forest was lower in the three layers studied compared to the soil under coffee and different weed managements. The different weed managements used in the interrows did not influence soil bulk density and organic carbon content of Latossol, in the 25-28 cm layer, compared to the soil under native forest (MATA).
Balota E.L.,Instituto Agronomico do Parana IAPAR |
Revista Brasileira de Fruticultura | Year: 2011
The objective of this work was to evaluate the alterations in carbon and nitrogen mineralization due to different soil tillage systems and groundcover species for intercropped orange trees. The experiment was established in an Ultisol soil (Typic Paleudults) originated from Caiuá sandstone in northwestern of the state of Paraná, Brazil, in an area previously cultivated with pasture (Brachiaria humidicola). Two soil tillage systems were evaluated: conventional tillage (CT) in the entire area and strip tillage (ST) with a 2-m width, each with different groundcover vegetation management systems. The citrus cultivar utilized was the 'Pera' orange (Citrus sinensis) grafted onto a 'Rangpur' lime rootstock. The soil samples were collected at a 0-15-cm depth after five years of experiment development. Samples were collected from under the tree canopy and from the inter-row space after the following treatments: (1) CT and annual cover crop with the leguminous Calopogonium mucunoides; (2) CT and perennial cover crop with the leguminous peanut Arachis pintoi; (3) CT and evergreen cover crop with Bahiagrass Paspalum notatum; (4) CT and cover crop with spontaneous B. humidicola grass vegetation; and (5) ST and maintenance of the remaining grass (pasture) of B. humidicola. The soil tillage systems and different groundcover vegetation influenced the C and N mineralization, both under the tree canopy and in the inter-row space. The cultivation of B. humidicola under strip tillage provided higher potential mineralization than the other treatments in the inter-row space. Strip tillage increased the C and N mineralization compared to conventional tillage. The grass cultivation increased the C and N mineralization when compared to the others treatments cultivated in the inter-row space.
Fidalski J.,Instituto Agronomico do Parana IAPAR |
Chaves J.C.D.,Instituto Agronomico do Parana IAPAR
Coffee Science | Year: 2010
The objective of this work was to assess the soil fertility, nutritional status and yield of Iapar-59 coffee subjected to 4 exogenous applications on the il surface: 20 tha-1 of dry matter (grey mucuna, leucaena, pigeon pea, perennial peanut, brizantha grass, forage sorghum, sugarcane bagasse, sugarcane filter cake, orange pulp, raw sewage sludge, sewage sludge with virgin lime, coffee straw, bovine manure, chicken litter, chicken manure, sugarcane bagasse with chicken manure and swine manure); 200 m 3 ha -1 of swine slurry; 95 kg ha -1 of N (ammonium sulphate source). A field experiment was set up in 2002 in a Typic Haplorthox, in Paranavaí, northwestern region of Paraná state, Brazil. From 2003 to 2005 soil (0-5, 5-10, 10-20 and 20-40 cm) and leaf samples were collected and coffee growth and yield were assessed. Grey mucuna increased leaf N contents, leucaena increased soil K (5-40 cm) contents and sugarcane filter cake increased soil Ca (10-40 cm) concentrations. These alterations enhanced growth and yield.
Balota E.L.,Instituto Agronomico do Parana IAPAR |
Machineski O.,Instituto Agronomico do Parana IAPAR |
Matos M.A.,Instituto Agronomico do Parana IAPAR
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2012
The objective of this work was to evaluate the changes in microbial biomass C, N and P due to the application of pig slurry under different soil tillage systems. The experiment was established in a clayey Oxisol, Eutrophic Red Latossol in Palotina, PR. Different quantities of pig slurry (0, 30, 60 and 120 m3 ha-1 year-1) were applied to the soil prior to the summer and winter crop season under conventional tillage (CT) and no tillage (NT), in three replicates. The area was cultivated with soybean (Glycine max L.) or maize (Zea mays L.) in the summer and wheat (Triticum sativum Lam.) or oat (Avena sativa L.) in the winter. The soil samples were collected in March and October of 1998 and 1999 at depths of 0-5, 5-10 and 10-20 cm. The soil tillage and pig slurry application influenced the microbial biomass C, N and P. The microbial biomass and the microbial activity presented high sensibility to detect changes in the soil due to tillage and the application of pig slurry. The soil microbial biomass and Cmic/Corg relation increased as the quantity of applied pig slurry increased. The metabolic quotient under CT increased with depth while under NT it decreased. The soil microbial biomass was enriched in N and P under NT and as the quantity of applied pig slurry increased.