cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.19928895
title: Growth and physiological characteristics of the weed false johnsongrass ( Sorghum arundinaceum (Desv.) Stapf)

description: ABSTRACT Sorghum arundinaceum (Desv.) Stapf is a weed that belongs to the Poaceae family and is widespread throughout Brazil. Despite the frequent occurrence, infesting cultivated areas, there is little research concerning the biology and physiology of this species. The objective of this research was to evaluate the growth, carbon partitioning and physiological characteristics of the weed Sorghum arundinaceum in greenhouse. Plants were collected at regular intervals of seven days, from 22 to 113 days after transplanting (DAT). In each sample, we determined plant height, root volume, leaf area and dry matter, and subsequently we perfomed the growth analysis, we have determined the dry matter partitioning among organs, the accumulation of dry matter, the specific leaf area, the relative growth rate and leaf weight ratio. At 36, 78 and 113 DAT, the photosynthetic and transpiration rates, stomatal conductance, CO2 concentration and chlorophyll fluorescence were evaluated. The Sorghum arundinaceum reached 1.91 in height, with slow initial growth and allocated much of the biomass in the roots. The photosynthetic rate and the maximum quantum yield of FSII are similar throughout the growth cycle. At maturity the Sorghum arundinaceum presents higher values of transpiration rate, stomatal conductance and non-photochemical quenching coefficient (NPQ).
DOI: 10.6084/m9.figshare.19928897
title: Phenotypic correlations and path analysis for plant architecture traits and grain production in three generations of cowpea

description: ABSTRACT The objective of this study was to analyze the phenotypic correlation and path analysis of traits related to plant architecture, earliness and grain yield in F2, BC1 and BC2 generations, from crosses between cowpea cultivars BRS Carijó and BR14 Mulato. Most phenotypic correlations of the examined traits were concordant in statistical significance, with approximate values among the examined generations. For the trait seed weight, significant and positive phenotypic correlations were observed in the three generations only for the trait number of secondary branches. The values of the direct effects were in agreement with the values of the phenotypic correlations, which indicate true association by the phenotypic correlation among the traits of grain yield examined. Path analysis indicated that the selection of productive plants will result in early plants and an increased number of secondary branches. In F2, plants with shorter length of the main branch and shorter length of secondary branches can be obtained. The causal model explained 15 to 30% of the total variation in grain weight in relation to the traits examined. The analyses indicated the possibility of selecting plants with a higher and early grain yield, shorter length of primary branches and lower number of nodes, which are important variables for mechanical or semi-mechanical harvesting.
DOI: 10.6084/m9.figshare.19928897.v1
title: Phenotypic correlations and path analysis for plant architecture traits and grain production in three generations of cowpea

description: ABSTRACT The objective of this study was to analyze the phenotypic correlation and path analysis of traits related to plant architecture, earliness and grain yield in F2, BC1 and BC2 generations, from crosses between cowpea cultivars BRS Carijó and BR14 Mulato. Most phenotypic correlations of the examined traits were concordant in statistical significance, with approximate values among the examined generations. For the trait seed weight, significant and positive phenotypic correlations were observed in the three generations only for the trait number of secondary branches. The values of the direct effects were in agreement with the values of the phenotypic correlations, which indicate true association by the phenotypic correlation among the traits of grain yield examined. Path analysis indicated that the selection of productive plants will result in early plants and an increased number of secondary branches. In F2, plants with shorter length of the main branch and shorter length of secondary branches can be obtained. The causal model explained 15 to 30% of the total variation in grain weight in relation to the traits examined. The analyses indicated the possibility of selecting plants with a higher and early grain yield, shorter length of primary branches and lower number of nodes, which are important variables for mechanical or semi-mechanical harvesting.
DOI: 10.6084/m9.figshare.19928895.v1
title: Growth and physiological characteristics of the weed false johnsongrass ( Sorghum arundinaceum (Desv.) Stapf)

description: ABSTRACT Sorghum arundinaceum (Desv.) Stapf is a weed that belongs to the Poaceae family and is widespread throughout Brazil. Despite the frequent occurrence, infesting cultivated areas, there is little research concerning the biology and physiology of this species. The objective of this research was to evaluate the growth, carbon partitioning and physiological characteristics of the weed Sorghum arundinaceum in greenhouse. Plants were collected at regular intervals of seven days, from 22 to 113 days after transplanting (DAT). In each sample, we determined plant height, root volume, leaf area and dry matter, and subsequently we perfomed the growth analysis, we have determined the dry matter partitioning among organs, the accumulation of dry matter, the specific leaf area, the relative growth rate and leaf weight ratio. At 36, 78 and 113 DAT, the photosynthetic and transpiration rates, stomatal conductance, CO2 concentration and chlorophyll fluorescence were evaluated. The Sorghum arundinaceum reached 1.91 in height, with slow initial growth and allocated much of the biomass in the roots. The photosynthetic rate and the maximum quantum yield of FSII are similar throughout the growth cycle. At maturity the Sorghum arundinaceum presents higher values of transpiration rate, stomatal conductance and non-photochemical quenching coefficient (NPQ).
DOI: 10.6084/m9.figshare.19928898
title: The effects of planting density and nutrient addition on container-grown vegetative propagules of halophytic grasses

description: ABSTRACT The halophytic grasses Spartina alterniflora and Spartina densiflora are bioengineer species, which can be utilized on the mitigation of disturbed areas of salt marshes and mangroves, for coastal erosion control and to stabilize dredged material disposed in estuarine and coastal areas. The effects of planting density and fertilization with nitrogen (N) and phosphorus (P) on container-grown (0.15 m2; 7500 cm3) vegetative propagules of both species were evaluated under greenhouse conditions, through two experiments during the years 2009 and 2011. In 2009, only S. alterniflora was cultivated within 2 planting densities (133 and 400 propagules m-2) and 2 levels of fertilization (without addition and with total addition of 50.8 gN m-2 and 16 gP m-2). In 2011, containers with 80 propagules m-2 of both species received N and P fertilization rates of 2N:1P, 6N:1P, 10N:1P and 14N:1P (for a total addition of 115 gN m-2). NP fertilization stimulated leaf formation and, in fertilized containers, the average number of S. alterniflora tillers was twice larger than control treatments. However, initial planting densities of 400 or more propagules m-2 resulted in excessive vertical growth of S. alterniflora tillers (about 100 cm height), which can result into plant losses during handling and transplantation. For both species, the 2N:1P fertilization rate resulted in higher tillering.
DOI: 10.6084/m9.figshare.19928898.v1
title: The effects of planting density and nutrient addition on container-grown vegetative propagules of halophytic grasses

description: ABSTRACT The halophytic grasses Spartina alterniflora and Spartina densiflora are bioengineer species, which can be utilized on the mitigation of disturbed areas of salt marshes and mangroves, for coastal erosion control and to stabilize dredged material disposed in estuarine and coastal areas. The effects of planting density and fertilization with nitrogen (N) and phosphorus (P) on container-grown (0.15 m2; 7500 cm3) vegetative propagules of both species were evaluated under greenhouse conditions, through two experiments during the years 2009 and 2011. In 2009, only S. alterniflora was cultivated within 2 planting densities (133 and 400 propagules m-2) and 2 levels of fertilization (without addition and with total addition of 50.8 gN m-2 and 16 gP m-2). In 2011, containers with 80 propagules m-2 of both species received N and P fertilization rates of 2N:1P, 6N:1P, 10N:1P and 14N:1P (for a total addition of 115 gN m-2). NP fertilization stimulated leaf formation and, in fertilized containers, the average number of S. alterniflora tillers was twice larger than control treatments. However, initial planting densities of 400 or more propagules m-2 resulted in excessive vertical growth of S. alterniflora tillers (about 100 cm height), which can result into plant losses during handling and transplantation. For both species, the 2N:1P fertilization rate resulted in higher tillering.
DOI: 10.6084/m9.figshare.19928900
title: Use efficiency of variable rate of nitrogen prescribed by optical sensor in corn

description: ABSTRACT The efficiency of nitrogen fertilizer in corn is usually low, negatively affecting plant nutrition, the economic return, and the environment. In this context, a variable rate of nitrogen, prescribed by crop sensors, has been proposed as an alternative to the uniform rate of nitrogen traditionally used by farmers. This study tested the hypothesis that variable rate of nitrogen, prescribed by optical sensor, increases the nitrogen use efficiency and grain yield as compared to uniform rate of nitrogen. The following treatments were evaluated: 0; 70; 140; and 210 kg ha-1 under uniform rate of nitrogen, and 140 kg ha -1 under variable rate of nitrogen. The nitrogen source was urea applied on the soil surface using a distributor equipped with the crop sensor. In this study, the grain yield ranged from 10.2 to 15.5 Mg ha-1, with linear response to nitrogen rates. The variable rate of nitrogen increased by 11.8 and 32.6% the nitrogen uptake and nitrogen use efficiency, respectively, compared to the uniform rate of nitrogen. However, no significant increase in grain yield was observed, indicating that the major benefit of the variable rate of nitrogen was reducing the risk of environmental impact of fertilizer.
DOI: 10.6084/m9.figshare.19928900.v1
title: Use efficiency of variable rate of nitrogen prescribed by optical sensor in corn

description: ABSTRACT The efficiency of nitrogen fertilizer in corn is usually low, negatively affecting plant nutrition, the economic return, and the environment. In this context, a variable rate of nitrogen, prescribed by crop sensors, has been proposed as an alternative to the uniform rate of nitrogen traditionally used by farmers. This study tested the hypothesis that variable rate of nitrogen, prescribed by optical sensor, increases the nitrogen use efficiency and grain yield as compared to uniform rate of nitrogen. The following treatments were evaluated: 0; 70; 140; and 210 kg ha-1 under uniform rate of nitrogen, and 140 kg ha -1 under variable rate of nitrogen. The nitrogen source was urea applied on the soil surface using a distributor equipped with the crop sensor. In this study, the grain yield ranged from 10.2 to 15.5 Mg ha-1, with linear response to nitrogen rates. The variable rate of nitrogen increased by 11.8 and 32.6% the nitrogen uptake and nitrogen use efficiency, respectively, compared to the uniform rate of nitrogen. However, no significant increase in grain yield was observed, indicating that the major benefit of the variable rate of nitrogen was reducing the risk of environmental impact of fertilizer.
DOI: 10.6084/m9.figshare.19928901
title: Growth and plant mass of radish fertirrigated with different doses nitrogen

description: ABSTRACT The objective of the present study was to evaluate the effect of nitrogen doses applied via fertigation and associated with different types of crop establishment fertilization on growth and biomass of radish. The experiment was conducted in a greenhouse of the Academic Unit of Agricultural Engineering, Federal University of Campina Grande, from April to May 2014. Treatments consisted of five doses of nitrogen fertilizer applied by fertigation (0, 0.7, 1.4, 2.1 and 2.8g per pot) and three types of crop establishment fertilization (humus 2:2; NPK and control), arranged in a 5 x 3 factor design with four repetitions. The 15 treatments were arranged in 60 plots. The nitrogen source used in the study was urea, divided in three applications: the first application was carried out eight days after transplanting, the second, on day 15, and the third, on day 22. The crop establishment fertilization significantly influenced the growth variables and plant mass of the radish on day 35 after transplanting. The highest values of the variables (number of leaves, plant height, bulb diameter, leaf area, fresh mass of the aerial part, dry mass of the aerial part and root/aerial part were observed in the treatment with humus on day 35 after transplanting. The dose of 2.8g nitrogen per pot corresponding to 6.22g of urea per plant provided the highest yield for the variable number of leafs, leaf area and root length on day 35 after transplanting.
DOI: 10.6084/m9.figshare.19928903
title: Seasonality and potential of energy production from agricultural residual biomass in Campos Gerais, Paraná State

description: ABSTRACT This study aimed to evaluate the seasonal and spatial availability of harvesting residual biomass of the main grain crops in the region of Campos Gerais - PR, estimate the theoretical potential to electricity production from these residues, as well as identify cities in the region with greater potential for installation of biomass-fueled thermoelectric . Yield data of corn, soybean, wheat, barley, oat and black oat were obtained from the Secretary of Agriculture of Paraná, for the seasons 2008/2009 and 2009/2010, and through the index and harvest calendar, the production and seasonality of total residual biomass of these crops were estimated. Biomass samples were collected from these species and their higher heating value (HHV) and theoretical potential to electricity production were determined. Campos Gerais produced 3.862.130 (2008/2009) and 4.107.932 Mg ha-1 (2009/2010) of total residual biomass with the six crops evaluated. The availability of biomass was concentrated in March and April (about 60%), being negligible in December, January and between June and August. The residual biomass of harvesting grain showed an HHV comparable to forest species, with a total potential energy production of 3.932 (2008/2009) and 4.185 GWh year(1 (2009/2010). Among the cities, Tibagi and Castro are the most promising for the installation of a biomass-fueled thermoelectric , due to their larger production and better seasonal distribution of residuals.
DOI: 10.6084/m9.figshare.19928903.v1
title: Seasonality and potential of energy production from agricultural residual biomass in Campos Gerais, Paraná State

description: ABSTRACT This study aimed to evaluate the seasonal and spatial availability of harvesting residual biomass of the main grain crops in the region of Campos Gerais - PR, estimate the theoretical potential to electricity production from these residues, as well as identify cities in the region with greater potential for installation of biomass-fueled thermoelectric . Yield data of corn, soybean, wheat, barley, oat and black oat were obtained from the Secretary of Agriculture of Paraná, for the seasons 2008/2009 and 2009/2010, and through the index and harvest calendar, the production and seasonality of total residual biomass of these crops were estimated. Biomass samples were collected from these species and their higher heating value (HHV) and theoretical potential to electricity production were determined. Campos Gerais produced 3.862.130 (2008/2009) and 4.107.932 Mg ha-1 (2009/2010) of total residual biomass with the six crops evaluated. The availability of biomass was concentrated in March and April (about 60%), being negligible in December, January and between June and August. The residual biomass of harvesting grain showed an HHV comparable to forest species, with a total potential energy production of 3.932 (2008/2009) and 4.185 GWh year(1 (2009/2010). Among the cities, Tibagi and Castro are the most promising for the installation of a biomass-fueled thermoelectric , due to their larger production and better seasonal distribution of residuals.
DOI: 10.6084/m9.figshare.19928906
title: Growth analysis in lettuce cultivars in Southern of Piauí

description: ABSTRACT The aim of this study was to evaluate the growth and recommend the best one (s) of four lettuce cultivars in Southern Piaui. The experiment was carried out in a greenhouse with a randomized block design, with split-plot in time evaluation (20, 24, 28, 32, 36, 40 days after sowing - DAS), and the corresponding treatments to four cultivars (Americana Rafaela(r), Grand Rapids TBR(r), Crespa Repolhuda(r) and Repolhuda todo ano(r)) with five replications. We evaluated leaf area; leaf number; stem diameter; shoot fresh mass; shoot, root and total dry mass and physiological indexes of growth analysis. The cultivars showed significant effect in the studied parameters. Under the submitted conditions, the Americana Rafaela(r) and Repolhuda todo ano(r) lettuce cultivars showed better performance and greater morphological and physiological indexes. The cultivars Americana Rafaela(r) and Repolhuda todo ano(r) can be grown under Southern Piaui conditions.
DOI: 10.6084/m9.figshare.19928906.v1
title: Growth analysis in lettuce cultivars in Southern of Piauí

description: ABSTRACT The aim of this study was to evaluate the growth and recommend the best one (s) of four lettuce cultivars in Southern Piaui. The experiment was carried out in a greenhouse with a randomized block design, with split-plot in time evaluation (20, 24, 28, 32, 36, 40 days after sowing - DAS), and the corresponding treatments to four cultivars (Americana Rafaela(r), Grand Rapids TBR(r), Crespa Repolhuda(r) and Repolhuda todo ano(r)) with five replications. We evaluated leaf area; leaf number; stem diameter; shoot fresh mass; shoot, root and total dry mass and physiological indexes of growth analysis. The cultivars showed significant effect in the studied parameters. Under the submitted conditions, the Americana Rafaela(r) and Repolhuda todo ano(r) lettuce cultivars showed better performance and greater morphological and physiological indexes. The cultivars Americana Rafaela(r) and Repolhuda todo ano(r) can be grown under Southern Piaui conditions.
DOI: 10.6084/m9.figshare.19928910
title: Initial growth of Parkia platycephala (Benth.) and Enterolobium timbouva (Mart.) under field conditions in a Cerrado area

description: ABSTRACT The objective of the present study was to analyze the growth of Parkia platycephala and Enterolobium timbouva (Mimosaceae), tree species native to Cerrado, in a strictus sensus Cerrado area in the municipality of Porto Nacional, Tocantins. Twenty plants of each species were evaluated at thirty-day intervals during twenty-five months (February/2008 through February/2010). The following variables were analyzed: number of leaves produced, plant height, and stem diameter. Foliar phenology was also studied (August/2008 through February/2010) by analyzing five randomly-selected individuals of each species. Three branches of each individual were marked and all their leaves were evaluated in terms of emergence and abscission periods. Foliar herbivory was determined based on interval-scale classes of twenty-five per cent each. The results revealed that leaf production and growth in height in Parkia platycephala and Enterolobium timbouva were predominant during the rainy season. In terms of stem diameter, Parkia platycephala presented a better development when compared to Enterolobium timbouva. The relative growth rate increased expressively along the rainy season in both species. An increase in leaf predation was also observed during the wet season in the two species studied. As both species were exposed to the same environmental conditions, the greater relative growth rate observed in P. platycephala can be attributed to its physiological and anatomical features, which among other factors, contributed to a lower leaf predation by herbivores.
DOI: 10.6084/m9.figshare.19928910.v1
title: Initial growth of Parkia platycephala (Benth.) and Enterolobium timbouva (Mart.) under field conditions in a Cerrado area

description: ABSTRACT The objective of the present study was to analyze the growth of Parkia platycephala and Enterolobium timbouva (Mimosaceae), tree species native to Cerrado, in a strictus sensus Cerrado area in the municipality of Porto Nacional, Tocantins. Twenty plants of each species were evaluated at thirty-day intervals during twenty-five months (February/2008 through February/2010). The following variables were analyzed: number of leaves produced, plant height, and stem diameter. Foliar phenology was also studied (August/2008 through February/2010) by analyzing five randomly-selected individuals of each species. Three branches of each individual were marked and all their leaves were evaluated in terms of emergence and abscission periods. Foliar herbivory was determined based on interval-scale classes of twenty-five per cent each. The results revealed that leaf production and growth in height in Parkia platycephala and Enterolobium timbouva were predominant during the rainy season. In terms of stem diameter, Parkia platycephala presented a better development when compared to Enterolobium timbouva. The relative growth rate increased expressively along the rainy season in both species. An increase in leaf predation was also observed during the wet season in the two species studied. As both species were exposed to the same environmental conditions, the greater relative growth rate observed in P. platycephala can be attributed to its physiological and anatomical features, which among other factors, contributed to a lower leaf predation by herbivores.
DOI: 10.6084/m9.figshare.19928912
title: Cantaloupe melon ( Cucumis melo L.) conservation using hydrocooling

description: ABSTRACT Maintaining cantaloupe melon at field temperature impairs conservation as it speeds up cell metabolism and transpiration, and, consequently, reduces shelf life. This study aimed to evaluate the conservation of Torreon hybrid cantaloupe using the hydrocooling treatment. Fruits were harvested at the commercial maturity stage (60 days after planting), in the morning, at the Nova California Farm, municipality of Mossoró-RN, in September 2007. One set of fruit was immersed in chilled water at 5 ºC for 5 min, at the packing house, while the remaining set was not hydro cooled. Then, both sets (treated and untreated with hydrocooling) were pre-cooled in air forced tunnels at 7 ºC, until the temperature in the pulp reached 10 ºC. Both fruit sets were stored for 0, 14, 21, 28 and 35 days under modified atmosphere at 3 ± 1 oC and 90 ± 5% RH. After each storage period, the fruits were incubated in an atmosphere-controlled chamber at 20 ± 2 oC and 80 ± 5% de RH, for seven days. The following characteristics were evaluated: external and internal appearance, mass loss, soluble solids, firmness and titrable acidity. The experiment was arranged in a completely randomized split-plot design with four replications of three fruits. The plots consisted of the hydrocooling conditions (with and without fruit soaking in chilled water), and the sub-plots consisted of the storage times (0, 14, 21, 28 and 35 days).The treatment with hydrocooling was efficient in keeping the firmness and soluble solids of the fruits and shortened the pre-cooling time in the cooling tunnel. However, hydrocooling did not increase fruit shelf-life.