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Production components, grain yield and water use efficiency of irrigated cowpea
Get PDFCowpea cultivars, which are indicated for irrigated cropping, are recommended without proper assessment of their productive potential and water use efficiency in response to water regimes in the soil from different production environments. The aim of this study was to evaluate the production components, the yield performance and the efficiency of water use of cowpea cultivars in response to the application of irrigation depths under the soil and climate conditions of Bom Jesus, PI. The experiment was performed from June to August 2011 in a soil classified as sandy-textured Fluvic Neosol. The study was conducted in a randomized blocks design, with four replicates. The treatments were arranged in subdivided plots (irrigation depths in plots and cultivars in subplots). The cultivars BRS Aracê (semi-prostrate) and BRS Tumucumaque (semi-erect) were submitted to five irrigation depths (108.2, 214.7, 287.9, 426.1 and 527.7 mm). The number of pods per plant and the weight of one hundred grains are the main components related to grain yield. The cultivar BRS Tumucumaque presented a better yield performance (1697.2 kg ha-1) than the cultivar BRS Aracê (1233.8 kg ha-1), with the application of the irrigation depths of 527.7 and 522.4 mm, respectively. The highest water use efficiency (0.420 kg m-3) is obtained with the application of the irrigation depth of 108.2 mm in both cultivars.Cowpea cultivars, which are indicated for irrigated cropping, are recommended without proper assessment of their productive potential and water use efficiency in response to water regimes in the soil from different production environments. The aim of this study was to evaluate the production components, the yield performance and the efficiency of water use of cowpea cultivars in response to the application of irrigation depths under the soil and climate conditions of Bom Jesus, PI. The experiment was performed from June to August 2011 in a soil classified as sandy-textured Fluvic Neosol. The study was conducted in a randomized blocks design, with four replicates. The treatments were arranged in subdivided plots (irrigation depths in plots and cultivars in subplots). The cultivars BRS Aracê (semi-prostrate) and BRS Tumucumaque (semi-erect) were submitted to five irrigation depths (108.2, 214.7, 287.9, 426.1 and 527.7 mm). The number of pods per plant and the weight of one hundred grains are the main components related to grain yield. The cultivar BRS Tumucumaque presented a better yield performance (1697.2 kg ha-1) than the cultivar BRS Aracê (1233.8 kg ha-1), with the application of the irrigation depths of 527.7 and 522.4 mm, respectively. The highest water use efficiency (0.420 kg m-3) is obtained with the application of the irrigation depth of 108.2 mm in both cultivars
Relative yield of wheat in coexistence with concurrent plants as indicator of competitiveness
Get PDFOne of the factors that limit the yield of wheat is the weed competition, being the competitive potential of plants affected by their morphophysiological characteristics. The objective of this study was to determine the competitiveness of wheat when in coexistence with Italian ryegrass (Lolium multiflorum) and radish (Raphanus sativus) competitive plants or with wheat as simulator competition plant. There were realized four experiments in the greenhouse of the Agricultural Department of Environmental Sciences of the UFSM, Campus of Frederico Westphalen – RS, during July to September, 2012. The treatments were arranged in a replacement series, in the proportions of 100:00 (wheat monoculture), 75:25, 50:50, 25:75 and 100:00 (competitor plant monoculture) for wheat plants (cv. Fundacep Cristalino) and for Italian ryegrass, radish and wheat (cv. BRS Guamirim) as competitor plants. The wheat is more competitive than Italian ryegrass in initial coexistence, even in the smallest proportion of plants. The radish when intercropped with wheat demonstrates similar competitive potential for environmental resources to the crop. There is mutual beneficial effect when wheat cultivars Fundacep Cristalino and BRS Guamirim coexisted, and each cultivar seems to have mechanism to avoid competition.One of the factors that limit the yield of wheat is the weed competition, being the competitive potential of plants affected by their morphophysiological characteristics. The objective of this study was to determine the competitiveness of wheat when in coexistence with Italian ryegrass (Lolium multiflorum) and radish (Raphanus sativus) competitive plants or with wheat as simulator competition plant. There were realized four experiments in the greenhouse of the Agricultural Department of Environmental Sciences of the UFSM, Campus of Frederico Westphalen – RS, during July to September, 2012. The treatments were arranged in a replacement series, in the proportions of 100:00 (wheat monoculture), 75:25, 50:50, 25:75 and 100:00 (competitor plant monoculture) for wheat plants (cv. Fundacep Cristalino) and for Italian ryegrass, radish and wheat (cv. BRS Guamirim) as competitor plants. The wheat is more competitive than Italian ryegrass in initial coexistence, even in the smallest proportion of plants. The radish when intercropped with wheat demonstrates similar competitive potential for environmental resources to the crop. There is mutual beneficial effect when wheat cultivars Fundacep Cristalino and BRS Guamirim coexisted, and each cultivar seems to have mechanism to avoid competition
Edaphic arthropods in different successional stages of Atlantic forest and abandoned pasture areas
Get PDFThe vegetation may modifies the structure and composition of the community of edaphic arthropods. This study aimed to compare the community of edaphic arthropods in four areas of abandoned pasture (AP1, AP2, AP3, AP4) and four secondary native forest fragments in a successional gradient (FF1, FF2, FF3, FF4), in Itaboraí, Rio de Janeiro, Brazil. The areas are positioned on the hillside and the sampling was conducted in transects outlined in a toposequence (upper, middle and lower sections), where pitfall traps were installed in the dry season. The organisms were identified in taxonomic groups (class, order and family). Comparing the averages for AP and FF, there was no defined pattern in terms of the response of structural attributes (total abundance, richness, uniformity and diversity). Among the areas of FF, higher values of all of the structural attributes occurred in the intermediate stages of forest succession (FF2, FF3), compared to the initial (FF1) and advanced stages (FF4). On average for the FF, the most favored groups were Archaeognatha, Coleoptera, Entomobryomorpha, Pseudoscorpionida, Psocoptera and Symphypleona. On average for the areas of AP, the most favored groups were Acari, Araneae, Formicidae, Diplopoda and Auchenorrhyncha. Among the areas of FF, Sternorryncha, Symphyla and Thysanura were favored in FF1, while Coleoptera, Psocoptera, Pseudoscorpionida, Entomobryomorpha and Archaeognatha were favored in the other successional stages (FF2, FF3, FF4The vegetation may modifies the structure and composition of the community of edaphic arthropods. This study aimed to compare the community of edaphic arthropods in four areas of abandoned pasture (AP1, AP2, AP3, AP4) and four secondary native forest fragments in a successional gradient (FF1, FF2, FF3, FF4), in Itaboraí, Rio de Janeiro, Brazil. The areas are positioned on the hillside and the sampling was conducted in transects outlined in a toposequence (upper, middle and lower sections), where pitfall traps were installed in the dry season. The organisms were identified in taxonomic groups (class, order and family). Comparing the averages for AP and FF, there was no defined pattern in terms of the response of structural attributes (total abundance, richness, uniformity and diversity). Among the areas of FF, higher values of all of the structural attributes occurred in the intermediate stages of forest succession (FF2, FF3), compared to the initial (FF1) and advanced stages (FF4). On average for the FF, the most favored groups were Archaeognatha, Coleoptera, Entomobryomorpha, Pseudoscorpionida, Psocoptera and Symphypleona. On average for the areas of AP, the most favored groups were Acari, Araneae, Formicidae, Diplopoda and Auchenorrhyncha. Among the areas of FF, Sternorryncha, Symphyla and Thysanura were favored in FF1, while Coleoptera, Psocoptera, Pseudoscorpionida, Entomobryomorpha and Archaeognatha were favored in the other successional stages (FF2, FF3, FF
Productivity and rooting of olive mini-cuttings grown in a clonal mini-garden according to season
Get PDFThe mini-cuttings productivity in clonal mini-garden using the semi-hydroponic system is a promising technique for the olive propagation, to obtaining a satisfactory amount of cuttings and with good quality. The objective was to evaluate the mini-stumps productivity and rooting of olive mini-cuttings in successive collections at different times of year in a clonal mini-garden in a semi-hydroponic system. In each collection the productivity of the clonal mini-garden was evaluated counting the collected cuttings. The mini-cuttings were prepared with 3-5 cm long with leaf area reduced by 50% and placed in plastic boxes with vermiculite for a period of 80 days. The evaluated variables were: mini-stumps productivity, mini-stumps and mini-cuttings percentage of survival, rooting percentage and number and length of mini-cuttings root. The olive mini-cuttings presented higher productivity during the spring of 2014. The mini-cuttings rooting percentage collected during the evaluated periods demonstrated that mini-cutting is a viable technique for olive propagation when grown in clonal mini-garden using a semi-hydroponic system.The mini-cuttings productivity in clonal mini-garden using the semi-hydroponic system is a promising technique for the olive propagation, to obtaining a satisfactory amount of cuttings and with good quality. The objective was to evaluate the mini-stumps productivity and rooting of olive mini-cuttings in successive collections at different times of year in a clonal mini-garden in a semi-hydroponic system. In each collection the productivity of the clonal mini-garden was evaluated counting the collected cuttings. The mini-cuttings were prepared with 3-5 cm long with leaf area reduced by 50% and placed in plastic boxes with vermiculite for a period of 80 days. The evaluated variables were: mini-stumps productivity, mini-stumps and mini-cuttings percentage of survival, rooting percentage and number and length of mini-cuttings root. The olive mini-cuttings presented higher productivity during the spring of 2014. The mini-cuttings rooting percentage collected during the evaluated periods demonstrated that mini-cutting is a viable technique for olive propagation when grown in clonal mini-garden using a semi-hydroponic system
Morphophysiological biometry and grain production in cowpea under different phosphorus levels
Get PDFIn tropical and semi-arid regions of Brazil, phosphorus is one of the most limiting elements of cowpea productivity. The aim of this study was to assess the effects of applying five phosphorus doses in the soil on morpho-physiological and production components in three improved cultivars of cowpea. The experiment was carried out at the São Fernando farm located in José de Freitas, PI, Brazil, in a Plinthosol with a low phosphorus content. The experimental design was complete randomized block design with four replications in a 5 × 3 factorial scheme consisting of five phosphorus doses (0, 60, 120, 180, and 240 kg P2O5 ha−1) and three improved cowpea cultivars (BRS Guariba, BRS Tumucumaque, and BRS Cauamé). No interaction was observed between cultivars and phosphorus doses for any of the assessed variables. The cultivar BRS Tumucumaque showed the highest value for one-hundred-grain weight (21.0 g) and, together with BRS Guariba, the highest value of pod length. An increment was observed in growth (stem diameter, main branch length, leaf area, and shoot dry matter) and production characteristics (number of pods per plant, number of grains per pod, one-hundred-grain weight, and grain production per plant) in response to increases in phosphorus doses. The dose of 183.1 kg P2O5 ha−1 provided the maximum technical grain yield, estimated at 2,023.3 kg ha−1.In tropical and semi-arid regions of Brazil, phosphorus is one of the most limiting elements of cowpea productivity. The aim of this study was to assess the effects of applying five phosphorus doses in the soil on morpho-physiological and production components in three improved cultivars of cowpea. The experiment was carried out at the São Fernando farm located in José de Freitas, PI, Brazil, in a Plinthosol with a low phosphorus content. The experimental design was complete randomized block design with four replications in a 5 × 3 factorial scheme consisting of five phosphorus doses (0, 60, 120, 180, and 240 kg P2O5 ha−1) and three improved cowpea cultivars (BRS Guariba, BRS Tumucumaque, and BRS Cauamé). No interaction was observed between cultivars and phosphorus doses for any of the assessed variables. The cultivar BRS Tumucumaque showed the highest value for one-hundred-grain weight (21.0 g) and, together with BRS Guariba, the highest value of pod length. An increment was observed in growth (stem diameter, main branch length, leaf area, and shoot dry matter) and production characteristics (number of pods per plant, number of grains per pod, one-hundred-grain weight, and grain production per plant) in response to increases in phosphorus doses. The dose of 183.1 kg P2O5 ha−1 provided the maximum technical grain yield, estimated at 2,023.3 kg ha−1
Sources and doses of organic substrates in the production of tamarind rootstock
Get PDFIn order to evaluate the performance of different organic sources, the composition of the substrate to produce rootstocks of tamarind and nutritional status, an experiment was carried out in the seedling nursery at the Universidade Federal Rural do Semi-Árido Mossoró, RN. The experimental design was a randomized complete block, in a 3x4 factorial design with four replications. The first factor consisted of three organic sources (bovine manure, goat manure and commercial organic compound) and the second factor of four ratios of these sources (0, 20, 40 and 60% v v-1) mixed with soil. As a control was used only soil were 12 treatments with 10 plants per plot, totaling 480 plants. Morphological and nutritional characteristics were evaluated. The goat manure source provided the best results for the evaluated morphological characteristics. The proportion of 40% of organic matter, regardless of the organic source added to the substrate, favored the better development of tamarind seedlings.In order to evaluate the performance of different organic sources, the composition of the substrate to produce rootstocks of tamarind and nutritional status, an experiment was carried out in the seedling nursery at the Universidade Federal Rural do Semi-Árido Mossoró, RN. The experimental design was a randomized complete block, in a 3x4 factorial design with four replications. The first factor consisted of three organic sources (bovine manure, goat manure and commercial organic compound) and the second factor of four ratios of these sources (0, 20, 40 and 60% v v-1) mixed with soil. As a control was used only soil were 12 treatments with 10 plants per plot, totaling 480 plants. Morphological and nutritional characteristics were evaluated. The goat manure source provided the best results for the evaluated morphological characteristics. The proportion of 40% of organic matter, regardless of the organic source added to the substrate, favored the better development of tamarind seedlings
Spatial interpolation techniques for site-specific irrigation management in a mango orchard
Get PDFInterpolation techniques can be a suitable approach to apply site-specific management for irrigation in fruit fields. However, which interpolation method will produce more accurate maps? In order to respond this question, the aim of this study was to test the performance of spatial interpolation techniques for mapping soil physical properties for site-specific irrigation management purpose in a mango orchard in the Brazilian semi-arid region. The experimental site was structured in a grid of 60 georeferenced points, which correspond to the number of mango trees spaced about 8 × 10-m in a fruit field in Petrolina county, Pernambuco. Soil texture, bulk density, volumetric water content at -0.01; -0.033; -0.06; -0.1; and -1.5 MPa, and soil water available were determined. Stochastic and deterministic interpolation methods were tested. Soil physical properties did not show spatial dependence preventing the interpolation by stochastic method (Kriging). However, it was possible to interpolate using deterministic methods such as inverse distance weight (IDW), local polynomial interpolation (LPI), and Radial basis functions (RBF). IDW and RBF showed the best results of map quality for physical properties, however, all interpolation method showed relative small errors and could be all used for delineating zones for site-specific irrigation management.Interpolation techniques can be a suitable approach to apply site-specific management for irrigation in fruit fields. However, which interpolation method will produce more accurate maps? In order to respond this question, the aim of this study was to test the performance of spatial interpolation techniques for mapping soil physical properties for site-specific irrigation management purpose in a mango orchard in the Brazilian semi-arid region. The experimental site was structured in a grid of 60 georeferenced points, which correspond to the number of mango trees spaced about 8 × 10-m in a fruit field in Petrolina county, Pernambuco. Soil texture, bulk density, volumetric water content at -0.01; -0.033; -0.06; -0.1; and -1.5 MPa, and soil water available were determined. Stochastic and deterministic interpolation methods were tested. Soil physical properties did not show spatial dependence preventing the interpolation by stochastic method (Kriging). However, it was possible to interpolate using deterministic methods such as inverse distance weight (IDW), local polynomial interpolation (LPI), and Radial basis functions (RBF). IDW and RBF showed the best results of map quality for physical properties, however, all interpolation method showed relative small errors and could be all used for delineating zones for site-specific irrigation management
Safflower genotypes submitted to soil density levels
Get PDFIt is essential to have knowledge of changes in soil structure, as a result of agricultural use and its relationship with crop development, especially those with potential for use in new regions, such as the cultivation of safflower (Carthamus tinctorius L.) in the Cerrado. In view of this dynamics, the objective was to evaluate the phytometric components of safflower genotypes submitted to levels of soil densities in Cerrado Oxisol. Ten safflower genotypes were then submitted to compaction (five densities: 1.0, 1, 2, 1.4, and 1.8 Mg m-3) in a completely randomized design with four replications under greenhouse conditions. The plots consisted of an overlap of three rings of polyvinylidene chloride of 0.01 m height each, and the treatments were applied in the intermediate layer. The phytometric components (plant height, number of leaves and stem diameter) and shoot dry mass of the crop were evaluated at 30, 60 and 90 days after sowing. There was no significant interaction between safflower genotypes and soil densities, with the effects being isolated for genotypes and/or densities when significant. For the phytometric characteristics evaluated, the genotypes PI250196, PI301049, PI305173, and PI305205 are more stable about the variations of soil density in comparison to the others. The phytometric components and dry mass of safflower shoot are impaired from the mean density of 1.2 Mg m-3.It is essential to have knowledge of changes in soil structure, as a result of agricultural use and its relationship with crop development, especially those with potential for use in new regions, such as the cultivation of safflower (Carthamus tinctorius L.) in the Cerrado. In view of this dynamics, the objective was to evaluate the phytometric components of safflower genotypes submitted to levels of soil densities in Cerrado Oxisol. Ten safflower genotypes were then submitted to compaction (five densities: 1.0, 1, 2, 1.4, and 1.8 Mg m-3) in a completely randomized design with four replications under greenhouse conditions. The plots consisted of an overlap of three rings of polyvinylidene chloride of 0.01 m height each, and the treatments were applied in the intermediate layer. The phytometric components (plant height, number of leaves and stem diameter) and shoot dry mass of the crop were evaluated at 30, 60 and 90 days after sowing. There was no significant interaction between safflower genotypes and soil densities, with the effects being isolated for genotypes and/or densities when significant. For the phytometric characteristics evaluated, the genotypes PI250196, PI301049, PI305173, and PI305205 are more stable about the variations of soil density in comparison to the others. The phytometric components and dry mass of safflower shoot are impaired from the mean density of 1.2 Mg m-3
Rooting of semihardwood cuttings of olive: indolbutyric acid, calcium and Azospirillum brasilense
Get PDFNowadays the semihardwood cuttings of olive is the most used method to produce seedlings of this specie; however, it is necessary to improve the efficiency of this method to enable the intensive exploitation of this fruit crop and reduce the seedling production costs. Thus, two experiments were conducted concurrently in sand bed, under a canvased shelter of the State University of Western Paraná (Brazil) to evaluate the number and average length of roots per cuttings, the percentage of rooted cuttings, cuttings with callus and dead cuttings. In the first experiment cuttings of olive cultivars Arbequina, Maria da Fé and clone 2 were treated with IBA (3.0 g L-1) associated with calcium concentration at 0.0; 0.25; 0.50 and 1.0 mmol L-1, implanted in a completely randomized design in a split plot design, with four replications containing ten cutting each, under intermittent mist. For this experiment the Arbequina cultivar presented the highest average number of roots per cutting and the highest percentage of rooted cuttings, but Maria da Fé cultivar promoted the highest average of cuttings with callus. In the second experiment Clone 2 cuttings were submitted to calcium (0.5 mmol L-1) and IBA (3.0 g L-1), and substrate inoculation with Azospirillum brasilense bacterium, implanted in a completely randomized design containing three replications of ten cuttings each. In this experiment, the highest percentage of rooted cuttings was obtained for IBA (3.0 g L-1) + A. brasilense.Nowadays the semihardwood cuttings of olive is the most used method to produce seedlings of this specie; however, it is necessary to improve the efficiency of this method to enable the intensive exploitation of this fruit crop and reduce the seedling production costs. Thus, two experiments were conducted concurrently in sand bed, under a canvased shelter of the State University of Western Paraná (Brazil) to evaluate the number and average length of roots per cuttings, the percentage of rooted cuttings, cuttings with callus and dead cuttings. In the first experiment cuttings of olive cultivars Arbequina, Maria da Fé and clone 2 were treated with IBA (3.0 g L-1) associated with calcium concentration at 0.0; 0.25; 0.50 and 1.0 mmol L-1, implanted in a completely randomized design in a split plot design, with four replications containing ten cutting each, under intermittent mist. For this experiment the Arbequina cultivar presented the highest average number of roots per cutting and the highest percentage of rooted cuttings, but Maria da Fé cultivar promoted the highest average of cuttings with callus. In the second experiment Clone 2 cuttings were submitted to calcium (0.5 mmol L-1) and IBA (3.0 g L-1), and substrate inoculation with Azospirillum brasilense bacterium, implanted in a completely randomized design containing three replications of ten cuttings each. In this experiment, the highest percentage of rooted cuttings was obtained for IBA (3.0 g L-1) + A. brasilense