cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.20011316
title: Macronutrients uptake rate and biomass partitioning during early growth of Jatropha plants

description: ABSTRACT Jatropha seeds oil can replace fossil fuels, but the nutrient supply management for this species is not fully described. The objective with this work was to establish curves of macronutrient (nitrogen - N; phosphorus - P; potassium - K; calcium - Ca; magnesium - Mg and sulfur - S) content in leaves, stem and roots, and to evaluate the relative growth rate (RGR), absolute growth rate (AGR) and the foliar mass ratio (FMR). The experiment was arranged in completely randomized design with five replications. Jatropha plants were grown in nutrient solution and collected at intervals of 14 up to 119 days after treatments started. The period of highest uptake of nutrients occurred from 7 to 35 days after treatments started, which coincides with highest AGR, RGR, FMR and accumulation of dry biomass. The highest Ca and Mg accumulation occurred in the leaves (respectively 48% and 47% of the total taken up), while N, K, S and P were mostly accumulated in the stem (58%, 56%, 56% and 53%, respectively). The nutrients more taken up by Jatropha plants were N and Ca, and the order of macronutrients uptake was: N &gt; Ca &gt; K &gt; Mg &gt; S &gt; P. Jatropha plants have shown high macronutrients content on its early development, indicating the importance of nutritional management to achieve reliable biomass yield.
DOI: 10.6084/m9.figshare.20011316.v1
title: Macronutrients uptake rate and biomass partitioning during early growth of Jatropha plants

description: ABSTRACT Jatropha seeds oil can replace fossil fuels, but the nutrient supply management for this species is not fully described. The objective with this work was to establish curves of macronutrient (nitrogen - N; phosphorus - P; potassium - K; calcium - Ca; magnesium - Mg and sulfur - S) content in leaves, stem and roots, and to evaluate the relative growth rate (RGR), absolute growth rate (AGR) and the foliar mass ratio (FMR). The experiment was arranged in completely randomized design with five replications. Jatropha plants were grown in nutrient solution and collected at intervals of 14 up to 119 days after treatments started. The period of highest uptake of nutrients occurred from 7 to 35 days after treatments started, which coincides with highest AGR, RGR, FMR and accumulation of dry biomass. The highest Ca and Mg accumulation occurred in the leaves (respectively 48% and 47% of the total taken up), while N, K, S and P were mostly accumulated in the stem (58%, 56%, 56% and 53%, respectively). The nutrients more taken up by Jatropha plants were N and Ca, and the order of macronutrients uptake was: N &gt; Ca &gt; K &gt; Mg &gt; S &gt; P. Jatropha plants have shown high macronutrients content on its early development, indicating the importance of nutritional management to achieve reliable biomass yield.
DOI: 10.6084/m9.figshare.20011315
title: Nutrient concentrations in the cherry tomato under application management of the nutrient solution with brackish water

description: ABSTRACT The aim of this work was to evaluate nutrient concentration in the leaf tissue of plants of the cherry tomato 'Rita', cultivated in a hydroponic system using water with increasing levels of salinity in the preparation of the nutrient solution, submitting the plants to different periods of exposure to salinity and irrigation frequency. The experiment was conducted in a greenhouse under a hydroponic system in pots containing substrate. The experimental design was of completely randomised blocks in a 6 x 2 x 2 factorial scheme, with six levels of salinity for the nutrient solution (3.01, 4.51, 5.94, 7.34, 8.71 and 10.40 dS m-1), two periods of plant exposure to salinity (51 and 6 days), and two irrigation frequencies (one irrigation per day and one irrigation every two days). The concentrations of nitrogen, phosphorus, potassium, calcium, magnesium, sulphur, sodium and chlorine were evaluated in the leaf tissue of the plants. The use of brackish water in the preparation of the nutritent solution promoted the effect of antagonistic interactions between the nutrients, affecting their concentrations. The increase in salinity resulted in increases in the concentration of sodium and chlorine, and a reduction in the concentration of potassium and nitrogen in the leaf tissue. The shorter exposure time of the plants to salinity resulted in smaller reductions in the concentration of potassium and nitrogen, and decreased the concentration of sodium and chlorine. Irrigation every two days affected the concentration of nitrogen, calcium and magnesium in the leaves.
DOI: 10.6084/m9.figshare.20011315.v1
title: Nutrient concentrations in the cherry tomato under application management of the nutrient solution with brackish water

description: ABSTRACT The aim of this work was to evaluate nutrient concentration in the leaf tissue of plants of the cherry tomato 'Rita', cultivated in a hydroponic system using water with increasing levels of salinity in the preparation of the nutrient solution, submitting the plants to different periods of exposure to salinity and irrigation frequency. The experiment was conducted in a greenhouse under a hydroponic system in pots containing substrate. The experimental design was of completely randomised blocks in a 6 x 2 x 2 factorial scheme, with six levels of salinity for the nutrient solution (3.01, 4.51, 5.94, 7.34, 8.71 and 10.40 dS m-1), two periods of plant exposure to salinity (51 and 6 days), and two irrigation frequencies (one irrigation per day and one irrigation every two days). The concentrations of nitrogen, phosphorus, potassium, calcium, magnesium, sulphur, sodium and chlorine were evaluated in the leaf tissue of the plants. The use of brackish water in the preparation of the nutritent solution promoted the effect of antagonistic interactions between the nutrients, affecting their concentrations. The increase in salinity resulted in increases in the concentration of sodium and chlorine, and a reduction in the concentration of potassium and nitrogen in the leaf tissue. The shorter exposure time of the plants to salinity resulted in smaller reductions in the concentration of potassium and nitrogen, and decreased the concentration of sodium and chlorine. Irrigation every two days affected the concentration of nitrogen, calcium and magnesium in the leaves.
DOI: 10.6084/m9.figshare.20011319
title: Spatial variability in a broiler shed environment with fogging system

description: ABSTRACT For fowl to better express their genetic characteristics, they need to be in a favourable environment, since the mechanism for controlling body temperature is only efficient when the temperature of the environment is within certain limits. The aim of this study was to evaluate the internal environment of poultry sheds, measuring temperature and relative humidity to calculate the Enthalpy Comfort Index (ECI), as well as measuring the litter temperature, and the indoor luminosity and air velocity of the sheds to prepare kriging maps. Evaluations were made during the dry season, in the morning and afternoon, in two identical sheds, using precision tools. The data for litter temperature, luminosity and air velocity were analysed with geostatistics, and maps were then elaborated to show the spatial distribution profiles of the variables throughout the sheds. From the maps, it was possible to see that in some places the temperature of the litter displayed very high values, reaching 33.8 ºC by day 42 of shed use, a temperature that is considered high and that can hinder thermal exchange and generate thermal discomfort for the birds. The kriging maps also showed that the ventilation system did not distribute the wind evenly, and that the greatest average air velocity was 2.6 m s-1. These factors demonstrated the need for corrections to the shed environment, to improve the thermal comfort of the birds.
DOI: 10.6084/m9.figshare.20011319.v1
title: Spatial variability in a broiler shed environment with fogging system

description: ABSTRACT For fowl to better express their genetic characteristics, they need to be in a favourable environment, since the mechanism for controlling body temperature is only efficient when the temperature of the environment is within certain limits. The aim of this study was to evaluate the internal environment of poultry sheds, measuring temperature and relative humidity to calculate the Enthalpy Comfort Index (ECI), as well as measuring the litter temperature, and the indoor luminosity and air velocity of the sheds to prepare kriging maps. Evaluations were made during the dry season, in the morning and afternoon, in two identical sheds, using precision tools. The data for litter temperature, luminosity and air velocity were analysed with geostatistics, and maps were then elaborated to show the spatial distribution profiles of the variables throughout the sheds. From the maps, it was possible to see that in some places the temperature of the litter displayed very high values, reaching 33.8 ºC by day 42 of shed use, a temperature that is considered high and that can hinder thermal exchange and generate thermal discomfort for the birds. The kriging maps also showed that the ventilation system did not distribute the wind evenly, and that the greatest average air velocity was 2.6 m s-1. These factors demonstrated the need for corrections to the shed environment, to improve the thermal comfort of the birds.
DOI: 10.6084/m9.figshare.20011321
title: Production of guava rootstock grown with water of different salinities and doses of nitrogen

description: ABSTRACT The scarcity of good-quality water and the occurrence of low-fertility soils are limiting factors in irrigated agriculture, especially in arid and semi-arid regions, which leads to the use of salt water and nitrogen fertiliser as alternatives for agricultural production in these regions. The aim of this work therefore, was to evaluate growth, biomass production and rootstock quality in the guava 'Crioula' under salt stress and doses of nitrogen fertiliser in a protected environment at CCTA/UFCG. The experimental design was of randomised blocks in a 5 x 4 factorial scheme, with four replications. The treatments consisted of a combination of five levels of electrical conductivity of the irrigation water (0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1) and four doses of nitrogen (70, 100, 130 and 160% of the recommended dose for guava seedlings). The dose of 541.1 mg N dm-3 soil (70% of the recommended N) stimulated growth, the accumulation of shoot biomass, and the quality of the guava 'Crioula' rootstock. Irrigation with an ECw greater than 0.3 dS m-1 had a negative effect on the absolute growth rate of the stem diameter, shoot dry matter, root to shoot ratio, and the Dickson quality index. Nitrogen fertiliser at 70 and 100% of the recommended level of N reduced the effect of irrigation water salinity on the relative growth rate of the stem diameter in the guava rootstock.
DOI: 10.6084/m9.figshare.20011321.v1
title: Production of guava rootstock grown with water of different salinities and doses of nitrogen

description: ABSTRACT The scarcity of good-quality water and the occurrence of low-fertility soils are limiting factors in irrigated agriculture, especially in arid and semi-arid regions, which leads to the use of salt water and nitrogen fertiliser as alternatives for agricultural production in these regions. The aim of this work therefore, was to evaluate growth, biomass production and rootstock quality in the guava 'Crioula' under salt stress and doses of nitrogen fertiliser in a protected environment at CCTA/UFCG. The experimental design was of randomised blocks in a 5 x 4 factorial scheme, with four replications. The treatments consisted of a combination of five levels of electrical conductivity of the irrigation water (0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1) and four doses of nitrogen (70, 100, 130 and 160% of the recommended dose for guava seedlings). The dose of 541.1 mg N dm-3 soil (70% of the recommended N) stimulated growth, the accumulation of shoot biomass, and the quality of the guava 'Crioula' rootstock. Irrigation with an ECw greater than 0.3 dS m-1 had a negative effect on the absolute growth rate of the stem diameter, shoot dry matter, root to shoot ratio, and the Dickson quality index. Nitrogen fertiliser at 70 and 100% of the recommended level of N reduced the effect of irrigation water salinity on the relative growth rate of the stem diameter in the guava rootstock.
DOI: 10.6084/m9.figshare.20011322
title: Interference of a weed community in the soybean crop in functions of sowing spacing

description: ABSTRACT The use of double row spacing on soybean crop is recent and consists of a new soybean production technology in Brazil and worldwide, so weed interference may be different in relation to single crop row. Thus, the objective of this work was to evaluate the weed interference in soybean crop in function of sowing spacing. The experimental design was randomized blocks and treatments were arranged in a factorial (2x16): two spacings, a double row spacing [(0.20 x 0.20 m) x 0.67 m] and a conventional single row spacing (0.45 x 0.45 m) and sixteen periods of weed management, being eight control periods in which soybean was kept free of weeds by increasing periods of 7; 14; 21; 28; 35; 42; 49 and 145 days after emergence and eight coexistence periods, when the crop was maintained in the presence of the weed community for the same periods. The Critical Timing of Weed Removal (CTWR) was lower in the double row spacing, with eight days, compared with single spacing that was of 18 days. The Critical Weed-Free Period (CWFP) was of 36 and 31 days for double and single row spacing, respectively, and the emergence of weeds after this period did not cause damage to the productivity, but the Critical Period of Weed Control (CPWC) was higher in double row spacing (28 days) compared to the single row, which was of 13 days. The spacing in double row had a higher grain yield than the spacing in single row.
DOI: 10.6084/m9.figshare.20011322.v1
title: Interference of a weed community in the soybean crop in functions of sowing spacing

description: ABSTRACT The use of double row spacing on soybean crop is recent and consists of a new soybean production technology in Brazil and worldwide, so weed interference may be different in relation to single crop row. Thus, the objective of this work was to evaluate the weed interference in soybean crop in function of sowing spacing. The experimental design was randomized blocks and treatments were arranged in a factorial (2x16): two spacings, a double row spacing [(0.20 x 0.20 m) x 0.67 m] and a conventional single row spacing (0.45 x 0.45 m) and sixteen periods of weed management, being eight control periods in which soybean was kept free of weeds by increasing periods of 7; 14; 21; 28; 35; 42; 49 and 145 days after emergence and eight coexistence periods, when the crop was maintained in the presence of the weed community for the same periods. The Critical Timing of Weed Removal (CTWR) was lower in the double row spacing, with eight days, compared with single spacing that was of 18 days. The Critical Weed-Free Period (CWFP) was of 36 and 31 days for double and single row spacing, respectively, and the emergence of weeds after this period did not cause damage to the productivity, but the Critical Period of Weed Control (CPWC) was higher in double row spacing (28 days) compared to the single row, which was of 13 days. The spacing in double row had a higher grain yield than the spacing in single row.
DOI: 10.6084/m9.figshare.20011325
title: Modified atmosphere together with refrigeration in the conservation of bananas resistant to black Sigatoka

description: ABSTRACT The aim of this work was to evaluate the chemical, physical and sensory characteristics of the Caipira and Pakovan Ken cultivars of the banana (Musa spp.), resistant to black Sigatoka (Mycosphaerella fijiensis Morelet), both with and without low-density polyethylene wrapping and together with refrigeration during the period of post-harvest storage. The experiment was carried out in 2012, in a randomised block design and an arrangement of lots split over time. A 3 x 2 factorial scheme was used for the lots, consisting of fruit with no wrapping and fruit wrapped in 10 and 16 µm polyethylene film, and two cultivars, Caipira and Pakovan Ken. The sub-lots consisted of evaluations made at intervals of six days (0, 6, 12, 18 and 24) and of two days (0, 2, 4, 6 and 8), for fruit stored at temperatures of 12, 15 and 25 ºC respectively. The following variables were evaluated: soluble solids, titratable acidity, ratio of soluble solids to titratable acidity, hydrogen potential, total soluble sugars, fruit colouration and sensory analysis. The polyethylene film together with the refrigeration enabled the fruit to be stored for 24 days, maintaining post-harvest characteristics suitable for consumption. The Pakovan Ken cultivar stood out when compared to the Caipira, with higher values for the fruit attributes under evaluation.
DOI: 10.6084/m9.figshare.20011325.v1
title: Modified atmosphere together with refrigeration in the conservation of bananas resistant to black Sigatoka

description: ABSTRACT The aim of this work was to evaluate the chemical, physical and sensory characteristics of the Caipira and Pakovan Ken cultivars of the banana (Musa spp.), resistant to black Sigatoka (Mycosphaerella fijiensis Morelet), both with and without low-density polyethylene wrapping and together with refrigeration during the period of post-harvest storage. The experiment was carried out in 2012, in a randomised block design and an arrangement of lots split over time. A 3 x 2 factorial scheme was used for the lots, consisting of fruit with no wrapping and fruit wrapped in 10 and 16 µm polyethylene film, and two cultivars, Caipira and Pakovan Ken. The sub-lots consisted of evaluations made at intervals of six days (0, 6, 12, 18 and 24) and of two days (0, 2, 4, 6 and 8), for fruit stored at temperatures of 12, 15 and 25 ºC respectively. The following variables were evaluated: soluble solids, titratable acidity, ratio of soluble solids to titratable acidity, hydrogen potential, total soluble sugars, fruit colouration and sensory analysis. The polyethylene film together with the refrigeration enabled the fruit to be stored for 24 days, maintaining post-harvest characteristics suitable for consumption. The Pakovan Ken cultivar stood out when compared to the Caipira, with higher values for the fruit attributes under evaluation.
DOI: 10.6084/m9.figshare.20011328
title: Response of 'BRS Guamirim' wheat to the application of Azospirillum, nitrogen and growth-promoting substances

description: ABSTRACT Substances and microorganisms that promote plant growth have been made available to rural farmers to increase crop yields. This work aimed to evaluate nitrogen doses and products containing microorganisms, growth promoting substances or both, on the yield and production components of the 'BRS Guamirim' wheat cultivar, as well as evaluate whether the complementary addition of N by urea is effective in maintaining a higher yield in wheat inoculated with Azospirillum brasilense, and whether such inoculation can totally or partially replace nitrogen fertilisation in wheat. The experiment was conducted in Coxilha in the State of Rio Grande do Sul, Brazil, in the 2014 season. The experimental design was of randomised blocks with four replications. The study comprised nine treatments: one control; four products (Azospirillum brasilense, synthetic plant hormone, mineral plant stimulator and biofertiliser); one treatment with the simultaneous use of the four products; and three additional doses of nitrogen (0, 40 and 120 kg ha-1) together with Azospirillum. The wheat cultivar was evaluated for grain yield, yield components, apparent harvest index, hectolitre weight, shoot dry matter and N content, and vegetation index. The evaluated products, containing microorganisms and/or growth promoting substances, do not alter wheat grain yield in the absence of water or nutritional deficiency. Azospirillum brasilense does neither totally nor partially replace nitrogen fertilisation in the 'BRS Guamirim' wheat cultivar.
DOI: 10.6084/m9.figshare.20011328.v1
title: Response of 'BRS Guamirim' wheat to the application of Azospirillum, nitrogen and growth-promoting substances

description: ABSTRACT Substances and microorganisms that promote plant growth have been made available to rural farmers to increase crop yields. This work aimed to evaluate nitrogen doses and products containing microorganisms, growth promoting substances or both, on the yield and production components of the 'BRS Guamirim' wheat cultivar, as well as evaluate whether the complementary addition of N by urea is effective in maintaining a higher yield in wheat inoculated with Azospirillum brasilense, and whether such inoculation can totally or partially replace nitrogen fertilisation in wheat. The experiment was conducted in Coxilha in the State of Rio Grande do Sul, Brazil, in the 2014 season. The experimental design was of randomised blocks with four replications. The study comprised nine treatments: one control; four products (Azospirillum brasilense, synthetic plant hormone, mineral plant stimulator and biofertiliser); one treatment with the simultaneous use of the four products; and three additional doses of nitrogen (0, 40 and 120 kg ha-1) together with Azospirillum. The wheat cultivar was evaluated for grain yield, yield components, apparent harvest index, hectolitre weight, shoot dry matter and N content, and vegetation index. The evaluated products, containing microorganisms and/or growth promoting substances, do not alter wheat grain yield in the absence of water or nutritional deficiency. Azospirillum brasilense does neither totally nor partially replace nitrogen fertilisation in the 'BRS Guamirim' wheat cultivar.
DOI: 10.6084/m9.figshare.20011331
title: Cover crops, nitrogen doses, and inoculation with Azospirillum brasilense, in maize in the Cerrado

description: ABSTRACT With the aim of increasing productivity, and minimising costs and environmental impact, sustainable management techniques are necessary when growing maize. The aim of this study was to evaluate different cover crops (millet, crotalaria, pigeon pea, millet + crotalaria, millet + pigeon pea and fallow) and doses of N (0, 40, 80 and 120 kg ha-1), both with and without seed inoculation with Azospirillum brasilense of the maize crop, in the Cerrado region of Brazil. The experimental design was of randomised blocks, in a 6 x 4 x 2 factorial scheme, comprising 48 treatments with 4 replications. The study was carried out in the town of Selvíria, in the State of Mato Grosso do Sul. Plant cover, except for the pigeon pea in the first year and the fallow in the second year, produced enough residue (6 t ha-1) to maintain the no-tillage system in the Cerrado region, especially the treatment with millet + crotalaria. Maize production in succession to the pigeon pea and the millet + crotalaria was higher. In an area with a stabilised no-tillage system, the supply of nitrogen using fertiliser, gives an increase in productivity up to a dose of 114 kg N ha-1. Inoculating the seeds with Azospirillum brasilense gave a smaller final plant population, less plant height and lower 100-grain weight.