cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.5668003
title: Agronomic performance of 'BRS' Itaim cowpea beans at different planting densities under no-tillage and conventional systems

description: ABSTRACT Cowpea beans play an important role in Brazilian farming, mainly in northern and northeastern regions, where it is widely grown among smallholder farmers. In recent years, commercial farmers have expanded its cultivation, mostly to the Midwest. This study aimed at evaluating the planting density of 'BRS Itaim' black-eyed cowpea beans under conventional (CT) and no-tillage (NT), with 75% mulch in the first year. Two experiments (CT and NT) were conducted at Embrapa Meio-Norte in Teresina - PI (Brazil), during the 2014/2015 harvest. Both experiments were carried out in a randomized block design with four replicates, considering the planting densities (PD) 12, 16, 20, 24, and 28 plants m-2. In both systems, grain yields (GY) and the number of pods per unit area (NPA) responded quadratically to an increase in PD, while a linear decreasing response was observed for the number of pods per unit area. The maximum grain yields (GY) were 1,492 kg ha-1 (23.8 plants m-2) and 1,136 kg ha-1 (23.2 plants m-2) under CT and NT, respectively. The NPA was most correlated with GY, presenting a value of 0.74 (. &lt;0.01). The survival rate of cowpea seedlings was 94% under CT and 88% under NT. This larger reduction under NT might be attributed to a higher incidence of fungi in the soil under this system (e.g. Furasium solani, Fusarium oxysporum, Macrophomina phaseolina, Pythium spp, Sclerotium rolfsii and Rhizoctonia solani).
DOI: 10.6084/m9.figshare.5668003.v1
title: Agronomic performance of 'BRS' Itaim cowpea beans at different planting densities under no-tillage and conventional systems

description: ABSTRACT Cowpea beans play an important role in Brazilian farming, mainly in northern and northeastern regions, where it is widely grown among smallholder farmers. In recent years, commercial farmers have expanded its cultivation, mostly to the Midwest. This study aimed at evaluating the planting density of 'BRS Itaim' black-eyed cowpea beans under conventional (CT) and no-tillage (NT), with 75% mulch in the first year. Two experiments (CT and NT) were conducted at Embrapa Meio-Norte in Teresina - PI (Brazil), during the 2014/2015 harvest. Both experiments were carried out in a randomized block design with four replicates, considering the planting densities (PD) 12, 16, 20, 24, and 28 plants m-2. In both systems, grain yields (GY) and the number of pods per unit area (NPA) responded quadratically to an increase in PD, while a linear decreasing response was observed for the number of pods per unit area. The maximum grain yields (GY) were 1,492 kg ha-1 (23.8 plants m-2) and 1,136 kg ha-1 (23.2 plants m-2) under CT and NT, respectively. The NPA was most correlated with GY, presenting a value of 0.74 (. &lt;0.01). The survival rate of cowpea seedlings was 94% under CT and 88% under NT. This larger reduction under NT might be attributed to a higher incidence of fungi in the soil under this system (e.g. Furasium solani, Fusarium oxysporum, Macrophomina phaseolina, Pythium spp, Sclerotium rolfsii and Rhizoctonia solani).
DOI: 10.6084/m9.figshare.5861760
title: Changes in attributes of soils subjected to fallow in desertification hotspot

description: ABSTRACT Soils in semi-arid regions have been degraded by overgrazing, which reduces the production capacity and, in certain situations, leads to desertification. An alternative to recover degraded areas is the fallow period, which works through the resilience of the soil itself, increasing the supply of organic matter and improving soil physical properties. Thus, the objective of this study was to test the hypothesis that 14-year grazing exclusion improves soil physical and chemical attributes in degraded areas under desertification. The study was conducted in Irauçuba, Ceará State, Brazil. The experimental design was completely randomized, in a 4 x 2 factorial scheme corresponding to four areas and two managements (overgrazing and fallow), with four replicates, plus an area with native vegetation (reference), with characteristics of secondary vegetation. Fallow led to improvements in soil physical and chemical attributes after 14 years; however, in comparison to the study conducted in the same area with a 7-year fallow period, there were few alterations. Organic carbon content was higher in fallow areas than in overgrazing areas, and the fraction in highest proportion was the mineral-associated organic carbon.
DOI: 10.6084/m9.figshare.5861760.v1
title: Changes in attributes of soils subjected to fallow in desertification hotspot

description: ABSTRACT Soils in semi-arid regions have been degraded by overgrazing, which reduces the production capacity and, in certain situations, leads to desertification. An alternative to recover degraded areas is the fallow period, which works through the resilience of the soil itself, increasing the supply of organic matter and improving soil physical properties. Thus, the objective of this study was to test the hypothesis that 14-year grazing exclusion improves soil physical and chemical attributes in degraded areas under desertification. The study was conducted in Irauçuba, Ceará State, Brazil. The experimental design was completely randomized, in a 4 x 2 factorial scheme corresponding to four areas and two managements (overgrazing and fallow), with four replicates, plus an area with native vegetation (reference), with characteristics of secondary vegetation. Fallow led to improvements in soil physical and chemical attributes after 14 years; however, in comparison to the study conducted in the same area with a 7-year fallow period, there were few alterations. Organic carbon content was higher in fallow areas than in overgrazing areas, and the fraction in highest proportion was the mineral-associated organic carbon.
DOI: 10.6084/m9.figshare.5861946
title: Electrochemical attributes of water from Cerrado wetlands (Veredas), Triângulo Mineiro region, Brazil

description: ABSTRACT Veredas are wetlands typically found in the Brazilian Cerrado playing important environmental functions. The hydromorphic conditions control important processes and reactions occurring in these environments. The objective of this study was to assess the pH, redox potential (Eh), and electrolytic conductivity (EC) of water from five veredas located in the Triângulo Mineiro region, nearby Uberlândia and Uberaba, Minas Gerais State, Brazil. The pH and EC of water samples (in triplicate) collected in different positions (upper, middle and bottom) of the selected wetlands were monitored monthly from September 2014 to September 2015. Eh was monitored in an incubation experiment using soil samples from the superficial layer (0-20 cm) and subsurface layer (40-70 cm) of the middle position of two of the selected veredas. In general, pH ranged from 3.4 to 6.5 throughout the year. For EC, the values ranged from 1.0 to 67.0 µS cm-1. Most of the year, pH was between 4.2 and 5.1 and EC was around 9.0 µS cm-1. Under laboratory conditions, Eh decreased from oxidic conditions to suboxidic (reduced) conditions. There were no significant differences between the wetlands and soil layers regarding the variation of Eh.
DOI: 10.6084/m9.figshare.5861946.v1
title: Electrochemical attributes of water from Cerrado wetlands (Veredas), Triângulo Mineiro region, Brazil

description: ABSTRACT Veredas are wetlands typically found in the Brazilian Cerrado playing important environmental functions. The hydromorphic conditions control important processes and reactions occurring in these environments. The objective of this study was to assess the pH, redox potential (Eh), and electrolytic conductivity (EC) of water from five veredas located in the Triângulo Mineiro region, nearby Uberlândia and Uberaba, Minas Gerais State, Brazil. The pH and EC of water samples (in triplicate) collected in different positions (upper, middle and bottom) of the selected wetlands were monitored monthly from September 2014 to September 2015. Eh was monitored in an incubation experiment using soil samples from the superficial layer (0-20 cm) and subsurface layer (40-70 cm) of the middle position of two of the selected veredas. In general, pH ranged from 3.4 to 6.5 throughout the year. For EC, the values ranged from 1.0 to 67.0 µS cm-1. Most of the year, pH was between 4.2 and 5.1 and EC was around 9.0 µS cm-1. Under laboratory conditions, Eh decreased from oxidic conditions to suboxidic (reduced) conditions. There were no significant differences between the wetlands and soil layers regarding the variation of Eh.
DOI: 10.6084/m9.figshare.5861259
title: Humic acid-phosphate fertilizer interaction and extractable phosphorus in soils of contrasting texture

description: ABSTRACT Extractable phosphorus (P) in soil depends on soil test employed, reactivity of fertilizer and interaction of P added to the soil properties, including organic matter. The aim of this paper was to assess the contents of P extracted from Red Latosol (LVd) and Quartzarenic Neosol (RQ) samples, incubated with 0; 5; 10; 50 or 100 mg kg-1 C-humic acid (C-HA) and 400 mg kg-1 of P, via Araxá phosphate rock (AP), Bayóvar reactive phosphate rock (BP) or single superphosphate (SS). Thus, it was adopted a five (C-HA concentrations) x three (P sources) factorial arrangement, using a randomized block design with three replications. The mixtures of soil, C-HA concentrations and P sources were incubated for 60 days; in sequence, the soil P was extracted by solutions of Bray-1, Mehlich-1 and Mehlich-3 and mixed ion exchange resin. In the LVd and RQ samples, the addition of C-HA reduced extractable phosphorus when the source was AP and BP. The levels of extractable P increased with the application of C-HA in RQ when the source was SS; the average concentration of 50 mg kg-1 C-AH provided the maximum extractable P by Bray-1, Mehlich-3 and mixed resin. The pH is the chemical attribute that most influence the extractable P content of the soil.
DOI: 10.6084/m9.figshare.5861259.v1
title: Humic acid-phosphate fertilizer interaction and extractable phosphorus in soils of contrasting texture

description: ABSTRACT Extractable phosphorus (P) in soil depends on soil test employed, reactivity of fertilizer and interaction of P added to the soil properties, including organic matter. The aim of this paper was to assess the contents of P extracted from Red Latosol (LVd) and Quartzarenic Neosol (RQ) samples, incubated with 0; 5; 10; 50 or 100 mg kg-1 C-humic acid (C-HA) and 400 mg kg-1 of P, via Araxá phosphate rock (AP), Bayóvar reactive phosphate rock (BP) or single superphosphate (SS). Thus, it was adopted a five (C-HA concentrations) x three (P sources) factorial arrangement, using a randomized block design with three replications. The mixtures of soil, C-HA concentrations and P sources were incubated for 60 days; in sequence, the soil P was extracted by solutions of Bray-1, Mehlich-1 and Mehlich-3 and mixed ion exchange resin. In the LVd and RQ samples, the addition of C-HA reduced extractable phosphorus when the source was AP and BP. The levels of extractable P increased with the application of C-HA in RQ when the source was SS; the average concentration of 50 mg kg-1 C-AH provided the maximum extractable P by Bray-1, Mehlich-3 and mixed resin. The pH is the chemical attribute that most influence the extractable P content of the soil.
DOI: 10.6084/m9.figshare.5861283
title: Apparent soil electrical conductivity in two different soil types

description: ABSTRACT Mapping the apparent soil electrical conductivity (ECa) has become important for the characterization of the soil variability in precision agriculture systems. Could the ECa be used to locate the soil sampling points for mapping the chemical and physical soil attributes? The objective of this work was to examine the relations between ECa and soil attributes in two fields presenting different soil textures. In each field, 50 sampling points were chosen using a path that presented a high variability of ECa obtained from a preliminary ECa map. At each sampling point, the ECa was measured in soil depths of 0-20, 0-40 and 0-60 cm. In addition, at each point, soil samples were collected for the determination of physical and chemical attributes in the laboratory. The ECa data obtained for different soil depths was very similar. A large number of significant correlations between ECa and the soil attributes were found. In the sandy clay loam texture field there was no correlation between ECa and organic matter or between ECa and soil clay and sand content. However, a significant positive correlation was shown for the remaining phosphorus. In the sandy loam texture field the ECa had a significant positive correlation with clay content and a significant negative correlation with sand content. The results suggest that the mapping of apparent soil electrical conductivity does not replace traditional soil sampling, however, it can be used as information to delimit regions in a field that have similar soil attributes.
DOI: 10.6084/m9.figshare.5861283.v1
title: Apparent soil electrical conductivity in two different soil types

description: ABSTRACT Mapping the apparent soil electrical conductivity (ECa) has become important for the characterization of the soil variability in precision agriculture systems. Could the ECa be used to locate the soil sampling points for mapping the chemical and physical soil attributes? The objective of this work was to examine the relations between ECa and soil attributes in two fields presenting different soil textures. In each field, 50 sampling points were chosen using a path that presented a high variability of ECa obtained from a preliminary ECa map. At each sampling point, the ECa was measured in soil depths of 0-20, 0-40 and 0-60 cm. In addition, at each point, soil samples were collected for the determination of physical and chemical attributes in the laboratory. The ECa data obtained for different soil depths was very similar. A large number of significant correlations between ECa and the soil attributes were found. In the sandy clay loam texture field there was no correlation between ECa and organic matter or between ECa and soil clay and sand content. However, a significant positive correlation was shown for the remaining phosphorus. In the sandy loam texture field the ECa had a significant positive correlation with clay content and a significant negative correlation with sand content. The results suggest that the mapping of apparent soil electrical conductivity does not replace traditional soil sampling, however, it can be used as information to delimit regions in a field that have similar soil attributes.
DOI: 10.6084/m9.figshare.5861853
title: Production efficiency and quality in seedlings of the ‘Pera’ orange interstocked with nucellar plantlet tissue

description: ABSTRACT Production of interstocked seedlings of the ‘Pera’ orange can be achieved through inarching of a rootstock on nucellar seedlings, with the subsequent grafting of a new scion. By this process, the interstocked seedling can be obtained in less time, but production efficiency is low, and no data on quality standards are available. The aim of this study was to evaluate the quality, time and production efficiency of ‘Pera’ orange (PO) seedlings interstocked with two types of nucellar plantlet tissue, using the ‘Flying Dragon’ trifoliate as rootstock. The experimental design was of randomised blocks, with four treatments, six replications and ten plants per plot. For the technique employed, nucellar plantlets of the ‘Seleta’ orange (SO) or Rangpur Lime (RL) were selected, followed by inarching with ‘Flying Dragon’ rootstock (FD) and budding with scions of the ‘Pera’ orange. The treatments consisted of different interstock combinations, PO/SO/FD and PO/RL/FD, and of non-interstock seedling combinations, PO/RL and SO/FD. Seedlings of the ‘Pera’ orange produced with interstocks of nucellar plantlets of the Rangpur Lime give seedling architecture of better quality. The interstocked seedlings were obtained 17 months after sowing the FD, with standards of physical quality similar to those required for commercial production, and with a production efficiency greater than 80%. When grown alone, FD requires more time to reach a sufficient diameter for grafting, delaying the production of seedlings.
DOI: 10.6084/m9.figshare.5861853.v1
title: Production efficiency and quality in seedlings of the ‘Pera’ orange interstocked with nucellar plantlet tissue

description: ABSTRACT Production of interstocked seedlings of the ‘Pera’ orange can be achieved through inarching of a rootstock on nucellar seedlings, with the subsequent grafting of a new scion. By this process, the interstocked seedling can be obtained in less time, but production efficiency is low, and no data on quality standards are available. The aim of this study was to evaluate the quality, time and production efficiency of ‘Pera’ orange (PO) seedlings interstocked with two types of nucellar plantlet tissue, using the ‘Flying Dragon’ trifoliate as rootstock. The experimental design was of randomised blocks, with four treatments, six replications and ten plants per plot. For the technique employed, nucellar plantlets of the ‘Seleta’ orange (SO) or Rangpur Lime (RL) were selected, followed by inarching with ‘Flying Dragon’ rootstock (FD) and budding with scions of the ‘Pera’ orange. The treatments consisted of different interstock combinations, PO/SO/FD and PO/RL/FD, and of non-interstock seedling combinations, PO/RL and SO/FD. Seedlings of the ‘Pera’ orange produced with interstocks of nucellar plantlets of the Rangpur Lime give seedling architecture of better quality. The interstocked seedlings were obtained 17 months after sowing the FD, with standards of physical quality similar to those required for commercial production, and with a production efficiency greater than 80%. When grown alone, FD requires more time to reach a sufficient diameter for grafting, delaying the production of seedlings.
DOI: 10.6084/m9.figshare.5861370
title: The potential of Mythimna sequax Franclemont eggs for the production of Trichogramma spp. after cryopreservation in liquid nitrogen

description: ABSTRACT The cryopreservation of noctuid eggs in liquid nitrogen has proved be a promising tool in the mass production of Trichogramma, however studies into this technique have only just begun. This study evaluated the response of different densities of the female of Trichogramma pretiosum Riley to the parasitism of Mythimna sequax eggs stored and not stored in liquid nitrogen, and the performance of females reared only in cryopreserved eggs. The study evaluated the influence of the number of T. pretiosum females (4, 8 and 12) released to parasitise 40 M. sequax eggs, stored and not stored for 15 days in liquid nitrogen, as well as the performance of T. pretiosum females reared in eggs stored for three generations and females reared in non-stored eggs. Parasitism by T. pretiosum in stored eggs was 84%, twice the value obtained in previous studies. The emergence of parasitoids was greater than 95% in both experiments. The performance of females raised in stored eggs did not differ from that of females raised in non-stored eggs. The data show that the technique of cryopreservation of M. sequax eggs may be a viable alternative in the mass production of T. pretiosum.
DOI: 10.6084/m9.figshare.5861370.v1
title: The potential of Mythimna sequax Franclemont eggs for the production of Trichogramma spp. after cryopreservation in liquid nitrogen

description: ABSTRACT The cryopreservation of noctuid eggs in liquid nitrogen has proved be a promising tool in the mass production of Trichogramma, however studies into this technique have only just begun. This study evaluated the response of different densities of the female of Trichogramma pretiosum Riley to the parasitism of Mythimna sequax eggs stored and not stored in liquid nitrogen, and the performance of females reared only in cryopreserved eggs. The study evaluated the influence of the number of T. pretiosum females (4, 8 and 12) released to parasitise 40 M. sequax eggs, stored and not stored for 15 days in liquid nitrogen, as well as the performance of T. pretiosum females reared in eggs stored for three generations and females reared in non-stored eggs. Parasitism by T. pretiosum in stored eggs was 84%, twice the value obtained in previous studies. The emergence of parasitoids was greater than 95% in both experiments. The performance of females raised in stored eggs did not differ from that of females raised in non-stored eggs. The data show that the technique of cryopreservation of M. sequax eggs may be a viable alternative in the mass production of T. pretiosum.
DOI: 10.6084/m9.figshare.5861364
title: Relative expression of CYP and Arabinogalactan genes in soybean seed coats

description: ABSTRACT The aim of this study was to evaluate the relative expression of two candidate genes, CYP (cyclophilin) and Arabinogalactan, possibly involved with seed quality, in contrasting soybean seed coats. The following genotypes were used: BMX Potência RR and CD 202, both with yellow coats, and TP and IAC, with black coats. The relative expression of the genes was evaluated by qPCR in seven development phases of the coats of the four genotypes at 25; 30; 35; 40; 45; 50 and 55 days after anthesis. The design was completely randomized, with three replicates. The data were submitted to analysis of variance and the means were compared via the Scott Knott test, at 5% probability. The CYP gene showed greater expression in the intermediate stages of development of the coats of the genotypes CD 202 and IAC, yellow coat and black coat, respectively. The A rabinogalactan gene presented greater expression in the final stages of coats development of BMX Potência RR.
DOI: 10.6084/m9.figshare.5861364.v1
title: Relative expression of CYP and Arabinogalactan genes in soybean seed coats

description: ABSTRACT The aim of this study was to evaluate the relative expression of two candidate genes, CYP (cyclophilin) and Arabinogalactan, possibly involved with seed quality, in contrasting soybean seed coats. The following genotypes were used: BMX Potência RR and CD 202, both with yellow coats, and TP and IAC, with black coats. The relative expression of the genes was evaluated by qPCR in seven development phases of the coats of the four genotypes at 25; 30; 35; 40; 45; 50 and 55 days after anthesis. The design was completely randomized, with three replicates. The data were submitted to analysis of variance and the means were compared via the Scott Knott test, at 5% probability. The CYP gene showed greater expression in the intermediate stages of development of the coats of the genotypes CD 202 and IAC, yellow coat and black coat, respectively. The A rabinogalactan gene presented greater expression in the final stages of coats development of BMX Potência RR.