cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14307162
title: Second-crop cowpea under residual phosphorus doses in the Brazilian Amazon

description: ABSTRACT The southeastern mesoregion of the Brazilian Pará state is an important soybean producer, and the second-crop system can increase the local agricultural production. However, Latosols with medium to very clayey texture predominate in the region and, despite being suitable for farming, they naturally have low levels of available phosphorus (P). This study aimed to evaluate the yield of second-crop cowpea [Vigna unguiculata (L.) Walp] under doses of residual P in a Yellow-Latosol. Two experiments were installed under field conditions. The experimental design was randomized blocks, with five treatments (residuals of 0, 50, 100, 150 and 200 kg ha-1 of P2O5) and four replications. The first experiment consisted of cultivating second-crop cowpea after the soybean harvest, with phosphate doses provided during the soybean planting, and the second of second-crop cowpea after the rice harvest, with phosphate doses provided during the rice planting. The 1,000-grain weight and production of pods, husks and grains were evaluated. The production of pods and husks were higher in the area with residual P. The highest yield was obtained in the residual dose of 200 kg ha-1 of P2O5, reaching a grain yield of 1,256 kg ha-1 after the soybean harvest and 885 kg ha-1 after the rice harvest.
DOI: 10.6084/m9.figshare.14307161
title: Contribution of phenolic acids and dimethyl sulfone to the allelopathic effect of invasive Tridax procumbens

description: ABSTRACT Tridax procumbens is an invasive weed with a strong allelopathic activity. In this study, the contribution of phenolic acids and dimethyl sulfone to the allelopathic effect of T. procumbens was evaluated against Raphanus sativus. Phenolic acids (benzoic, ellagic and ferulic), vanillin and dimethyl sulfone were identified and quantified from the strongest fraction of T. procumbens, in an allelopathic assay by high performance liquid chromatography and gas chromatography - mass spectrometry. The contribution of phenolic acids and dimethyl sulfone to the allelopathic effect of T. procumbens, expressed as a total activity, was evaluated by comparing the IC50 value to the concentration of each allelochemical, in a completely randomized design. The benzoic acid presented the strongest inhibitory effect (115 mg kg-1) and the highest contribution (0.483) to the allelopathic effect of T. procumbens, followed by vanillin, dimethyl sulfone and ferulic acid.
DOI: 10.6084/m9.figshare.14307159
title: Intercropping maize and succession crops alters the weed community in common bean under no-tillage

description: ABSTRACT Crop rotation is critical in the management of herbicide-resistant weed species. This study aimed to evaluate the effect of intercropping systems of maize with brachiaria or crotalaria on qualitative and quantitative parameters of the weed seedbank, along the succession of pearl millet, maize and common bean. Moreover, the effect of these crop rotation systems on the selection of specific weed species of the seedbank was also evaluated. The experimental design was randomized blocks, with four replications. The treatments were represented by three cropping systems in succession: pearl millet, single maize, common bean; pearl millet, maize intercropped with brachiaria, common bean; pearl millet, maize intercropped with crotalaria, common bean. The following phytosociological indexes were calculated: density, frequency and relative importance, diversity and equitability. The grain yield of maize and common bean were also quantified. Twenty-three weed species were identified, divided into 12 families, highlighting the Poaceae one, with the most important being Alternanthera tenella, Commelina benghalensis, Eleusine indica and Phyllanthus tenellus. The cropping system with single maize presented a lower density and diversity of weeds, but with a high selection of E. indica. The intercropping systems in the previous crop, as a guarantee of a higher weed diversity, could be use as alternative tools, different from the herbicides, to control weeds and improve the common bean yield. Regarding the weed control in the common bean, Crotalaria spectabilis presented better results in the previous maize-intercropping system than Urochloa ruziziensis.
DOI: 10.6084/m9.figshare.14307156
title: Emergence and growth of maize submitted to inoculant doses associated with saline water irrigation

description: ABSTRACT Salinity, in general, affects the plant growth and development, making it a limiting problem for the agricultural production. This study aimed to evaluate the effect of inoculant doses of Azospirillum brasilense on the emergence and growth of maize submitted to salinity concentrations of the irrigation water. The experiment was carried out in a greenhouse, with a randomized blocks design, in a 3 x 5 factorial [A. brasilense doses (0.0, 0.32 and 0.48 mL/100 seeds) and levels of electrical conductivity of the water (0.3, 0.6, 1.1, 1.7 and 2.3 dS m-1)], in 4 blocks, totaling 60 experimental units. The emergence percentage, emergence speed index, plant height, stem diameter, number of leaves, leaf area, leaf dry mass, stem dry mass, tassel dry mass and root dry mass were evaluated. The treatments between salinity and inoculation had no effect on seedling emergence. The salinity significantly affected growth; however, the number of leaves increased in 12.8 % (V8) and 18.8 % (V10), when comparing the difference between the lowest and highest studied salinity. As for the plant height, there was an increase of 3.7 % up to the threshold salinity of the crop (1.1 dS m-1). There was an increase in the root dry mass with the application of inoculant doses at each studied salt level.
DOI: 10.6084/m9.figshare.14307155
title: Nitrogen rates on the agronomic performance of second-crop corn single and intercropped with ruzigrass or showy rattlebox

description: ABSTRACT Topdressing nitrogen (N) rates may alter the second-crop corn performance, and this response may vary if the corn is grown single or intercropped with grass or leguminous species. This study aimed to evaluate the effect of topdressing N rates on the growth and productive performance of second-crop corn grown single or intercropped with ruzigrass (Urochloa ruziziensis) or showy rattlebox (Crotalaria spectabilis). The experiment was carried out in a randomized block design, with a split-plot arrangement and four replications. The plots consisted of corn grown single or intercropped with ruzigrass or showy rattlebox, while the subplots consisted of N rates (0, 60, 120, 180 and 240 kg ha-1). The evaluated variables were: SPAD index at R1; normalized difference vegetation index at V4 and V7; leaf area at R1; leaf and total corn dry mass at R1; grain and total corn dry mass at R6; number of ears per plant and grains per ear; 1,000-grain mass; and grain yield. In the absence of N fertilization and with topdressing of 60 kg ha-1 of N, the intercropping with U. ruziziensis reduces the growth and productive performance of second-crop corn. The topdressing N fertilization for second-crop corn intercropped with U. ruziziensis minimizes the forage competition on corn growth and provides a productive performance similar to monocropping from 120 kg ha-1 of N. The intercropping with C. spectabilis does not change the corn growth and productive performance, as well as the response to the topdressing N rates, when compared to monocropping, in the second crop cultivation.
DOI: 10.6084/m9.figshare.14307152
title: Manganese fertilization for sweet cassava production under organic management system

description: ABSTRACT Organic management farms in the Federal District, Brazil, usually present overlimed and overfertilized soils, with high content of organic matter and high pH. These conditions lead to a low availability of manganese to crops. Many sweet cassava (Manihot esculenta Crantz.) crops were diagnosed with Mn deficiency in the region, presenting low yields. In order to overcome such condition, an experiment was established comprising the following treatments: application of MnSO4 banded in rows; treatment of cassava cuttings with a MnSO4 solution before planting; application of MnSO4 and elemental sulfur (S0) banded in the rows, to acidify the soil, increasing the Mn solubility; and leaf spraying of a Mn solution. The best results were revealed when the Mn was applied by foliar spraying and using a combination of methods (treatment of cassava cuttings with Mn, and Mn and S0 applied to the soil before planting). This treatments provided a fresh root yield of 19.5 Mg ha-1, contrasting with the control treatment (3.6 Mg ha-1).
DOI: 10.6084/m9.figshare.14307149
title: Agro-economic performance of bur gherkin under staking systems

description: ABSTRACT The bur gherkin cultivation is predominantly carried out without a staking system, but problems such as the "white belly" and fruit rot occur in this system. This study aimed to evaluate staking systems for bur gherkin plants. The experimental design was randomized blocks, with five treatments (no staking, agricultural netting staking, Mexican staking, vertical ribbon with total secondary stem thinning and vertical ribbon with alternate secondary stem thinning) and four replicates. The fresh mass and number of fruits per plant, fruit length and average diameter, number and fresh mass of fruits with white belly per plant, fresh mass per fruit and total yield were evaluated, as well as the economic indicators gross income, net income, rate of return and profitability index. For all the staking systems, the incidence of fruits with white belly was lower. The agricultural netting (43.75 t ha-1), Mexican (35.94 t ha-1) and vertical ribbon with alternate secondary stem thinning (22.24 t ha-1) systems promoted yields superior to that for no staking. The best economic indicator (US$ 21,031.46 ha-1) was observed for the agricultural netting staking, which is the most recommended for the bur gherkin cultivation.
DOI: 10.6084/m9.figshare.14307147
title: Genetic divergence and path analysis in wheat cultivars under heat stress

description: ABSTRACT One of the biggest limitations for the wheat crop expansion to Brazilian tropical regions is the high temperature in the rainy season. This study aimed to select, based on genetic divergence and path analysis, cultivars that tolerate cultivation in the summer (heat stress). Nine wheat cultivars were sown, using a randomized block design with three replications, with plots consisting of 10 rows of 6 m and row spacing of 0.15 m. The highest grain yield and number of ears m-2 were observed for the CD 150 cultivar and the largest 1,000-grain weight for CD 116. BRS 220, IPR 136, IPR 144 and BRS Pardela had the highest number of sterile spikelets. The highest number of grains per ear was observed for CD 150, CD 116, BRS Pardela, IPR 130 and IPR 85, showing direct effects on grain yield, evidenced by the path analysis. CD 116 and CD 150 were the most productive cultivars and can be considered as possible parents in wheat breeding programs. IPR 85, CD 116, CD 108 and CD 150 showed a greater tolerance to high temperatures.
DOI: 10.6084/m9.figshare.14307146
title: Neoseiulus californicus preying on Tenuipalpus heveae

description: ABSTRACT The spread of Tenuipalpus heveae Baker (Acari: Tenuipalpidae) can be controlled by managing predatory species such as Neoseiulus californicus (McGregor) (Acari: Phytoseiidae). This study aimed to evaluate the predation of N. californicus at different biological phases on T. heveae at different development stages. The experiments were carried out under laboratory-controlled conditions, counting the number of predated individuals by development stage after 24, 48 and 72 h. N. californicus, in all phases, consumed T. heveae, with a higher consumption of nymphs and larvae by adult predators. Both sexes of adult predators exhibited predation efficiency, but females showed a greater acceptance of adult preys than males. The daily rate of adult predation decreased over time; however, the highest consumption took place in the first 24 h.
DOI: 10.6084/m9.figshare.14307143
title: Yield and profitability of flooded rice genotypes in relation to nitrogen doses and phosphorus and potassium application

description: ABSTRACT The use of hybrid genotypes is a good alternative for increasing the flooded rice yield. However, there is a need for validation of the fertilizer management under different edaphoclimatic conditions and its greater profitability. This study aimed to evaluate the grain yield and profitability of rice hybrids in relation to N doses and fertilization with P and K. Five hybrid cultivars and the conventional IRGA 424 CL cultivar combined with four N doses (0, 100, 150 and 200 kg ha-1) were evaluated, all with fixed doses of 90 kg ha-1 of P2O5 and 150 kg ha-1 of K2O, besides an additional treatment without the addition of fertilizers. The N application increases, on average, by 10 and 35 % the flooded rice yield in years with favorable and unfavorable climatic conditions, respectively. Regardless of the year and genotype, the highest yields are obtained with doses of N between 106 and 200 kg ha-1, with the most profitable dose being the 150 kg ha-1 one (22 % higher than for the absence of N). The hybrids produce an average of 20 % more grains than the IRGA 424 CL cultivar, increasing the profitability by 18 %. In soil with adequate P and K availability, there is no increase in yield due to the application of these nutrients. However, in deficient soil, the fertilization with P and K increases the grain yield by 21 %.
DOI: 10.6084/m9.figshare.14307141
title: Management of liquid swine manure: impact on mineral nitrogen dynamics and corn yield

description: ABSTRACT The agronomic efficiency of liquid swine manure (LSM) depends on the use of strategies to mitigate nitrogen (N) losses after its application to the soil, and thus preserve its fertilizing potential. In order to evaluate the injection of LSM into the soil and the addition of a nitrification inhibitor, as ways to increase its efficiency as a N source to the corn crop in the no-tillage system, an experiment was carried out under an Aluminofferic Red Latosol. The used treatments were: one control, surface application (total area) of LSM, injection of LSM in furrows, surface application (total area) of LSM + dicyandiamide (DCD), injection of LSM + DCD in furrows, and mineral fertilization. The mineral N in the soil and number of rows per ear, number of grains per row, 1,000-grain mass and grain yield for corn were evaluated. One day after the application of the treatments, the recovery of the mineral N in the soil with the injection of LSM exceeded by 10 kg ha-1 that observed with the superficial application. With DCD, the recovery of anionic forms (NO2- and NO3-) in the soil was lower in the first 20 days after the application, with the change in the N dynamics caused by DCD resulting in a higher content of mineral N at 30 days after sowing. The transformation rate for the anionic forms of mineral N in the soil is reduced with the addition of DCD. The injection of LSM with DCD does not differ from mineral fertilization, in terms of corn grain yield.
DOI: 10.6084/m9.figshare.14307140
title: Macronutrient accumulation curves in potato genotypes in the Brazilian Savanna

description: ABSTRACT Knowledge on the nutritional demands of different potato genotypes is necessary for the development of fertilizing recommendations. This study aimed to determine and compare the macronutrient accumulation curves in the Agata, Asterix, BRSIPR Bel and F183-08-01 potato genotypes, in order to subsidize the split fertilization that could meet the specific demands of each genotype. A randomized block design was used, with the treatments (genotypes × plant stages) arranged in a split-plot scheme, with three replications. The genotypes were grown in plots containing 75 plants each. The subplots within a plot contained four plants each and corresponded to the number of days after planting, when destructive samples of whole plants were collected. The plants from the subplots were harvested at 24, 38, 52, 66 and 80 days after planting, to estimate the dry mass accumulated by different parts of the plant (shoots + roots, tubers and whole plants), as well as to determine the macronutrient accumulation curves. F183-08-01 presented the highest total accumulation of N, Ca, Mg and S (141.37, 29.21, 25.16 and 22.36 kg ha-1, respectively). The highest rates of macronutrient accumulation for all the potato genotypes occurred at 24 days after planting, coinciding with the beginning of the tubers formation.
DOI: 10.6084/m9.figshare.14307137
title: Nitrogen fertilization management in white oat using spectral indices

description: ABSTRACT Remote sensing techniques have been considered a new technology in worldwide agriculture for diagnosing the plant nutritional demand. Fertilizer management efficiency is a goal to be achieved, and modern tools based on remote sensing are promising for monitoring the crop needs. This study aimed to evaluate the agronomic performance and relative economic return of white oat under nitrogen rates, as well as to verify whether the normalized difference vegetation index (NDVI) and leaf chlorophyll index (LCI) could be used for topdressing nitrogen fertilization management, in white oat. Treatments consisted of five topdressing nitrogen fertilization strategies: T1 - 160 kg ha-1 (reference rate); T2 - 90 kg ha-1 (recommended rate); T3 - 60 kg ha-1 (economic rate); T4 - 30 kg ha-1 (when NDVI &lt; 90 % of T1); and T5 - 30 kg ha-1 (when LCI &lt; 90 % of T1). The white oat did not respond to the topdressing nitrogen fertilization. Its temporal monitoring using spectral indices allowed dispensing the topdressing nitrogen fertilization without reducing the grain and biomass yields and the leaf nitrogen content, when compared to the recommended management (90 kg ha-1 of N as topdressing), with no differences between the evaluated spectral indices. Thus, both the NDVI and LCI spectral indices are promising tools for the topdressing nitrogen fertilization management in the white oat crop.
DOI: 10.6084/m9.figshare.14307132
title: Use of cassava wastewater in Capsicum chinense production

description: ABSTRACT The use of resources derived from the agricultural property itself to meet the needs of producers promotes the reduction of costs with commercial inputs and recycling of by-products, among them the liquid waste from the cassava flour production, called cassava wastewater, which can be an important fertilization source. This study aimed to evaluate the growth and production of Capsicum chinense Jacq., as a function of cassava wastewater doses associated with mineral fertilizer proportions. The experiment was conducted in a greenhouse, in a completely randomized design, with treatments distributed in a 3 x 5 factorial scheme, corresponding to 3 doses (0, 50 and 100 %) of the mineral fertilization recommended for the crop and 5 doses (0, 25, 50, 100 and 150 m³ ha-1) of cassava wastewater, with 4 replicates. The cassava wastewater doses influenced the crop yield, showing a linear trend. The dose of 150 m3 ha-1 promoted a yield equivalent to that obtained with the application of 100 % of the mineral fertilization recommended for this crop, thus enabling the partial or total replacement of this fertilization by cassava wastewater.
DOI: 10.6084/m9.figshare.14307131
title: Brassinosteroid accelerates the growth of Psidium hybrid during acclimatization of seedlings obtained from minicuttings

description: ABSTRACT Guava rootstocks can be multiplied by minicuttings in environment with a high relative humidity, being necessary an acclimatization period. Certain growth regulators favor the acclimatization, with brassinosteroids being successfully used in other fruit plants. This study aimed to shorten the multiplication time of the BRS Guaraçá hybrid by applying Biobras-16 (BB-16) during the acclimatization of seedlings obtained from minicuttings. The treatments consisted of five BB-16 concentrations (0, 0.1, 0.3, 0.5 and 1.0 mg L-1), applied in a randomized block design, in a split-plot arrangement, with four replications and five seedlings per plot, repeated at two seasons: winter and spring/summer. After 60 days of acclimatization, shoot and root growth indicators increased as a function of the BB-16 application, particularly at concentrations between 0.3 and 0.6 mg L-1. The brassinosteroid can be used to stimulate the growth of BRS Guaraçá seedlings obtained from minicuttings, shortening its production time and improving its seedling quality.
DOI: 10.6084/m9.figshare.14307129
title: Mulch decomposition and nitrogen, phosphorus and potassium release in vetiver grass at different plant densities

description: ABSTRACT In order to meet the need for nutrients or soil cover, when plants are used as green manure, it is necessary to determine the ideal plant population, as well as the amount and duration of released nutrients. This study aimed to assess the decomposition and nitrogen (N), phosphorus (P) and potassium (K) release rates of vetiver grass mulch. A split-plot arrangement was used, with the plots consisting of mulch decomposition times after cutting (0, 15, 25, 70 and 125 days) and the subplots of vetiver plant densities (1, 2, 3 and 4 plants m-2). A randomized block design was used, with four replications. The highest release rates for N, P and K were recorded during the first five days. The plant density of 3 plants m-2 exhibited the highest mulch dry weight at 125 days and contained more N, P and K, when compared to the populations of 1, 2 and 4 plants m-2.
DOI: 10.6084/m9.figshare.14307123
title: Relationship between photosynthetic pigments and corn production under nitrogen sources

description: ABSTRACT Nitrogen (N) is a dynamic element in the soil, so new nitrogen fertilization alternatives are required as a way of maximizing its efficiency. Besides, vegetation sensors are a way to assess and manage the nutritional demands of plants. This study aimed to evaluate the effect of nitrogen sources on photosynthetic pigments and their correlation with corn grain yield and dry biomass. The experiment was carried out in a randomized block design with nitrogen sources (mineral, organic and biological). Contents of chlorophyll a, b and total, as well as carotenoids, were evaluated. The chlorophyll indices evaluated by both methods were positively correlated with each other and with the grain yield per plant. Nitrogen fertilization 100 % mineral was superior, when compared to the other treatments, with increments of up to 44 %. There was a positive relationship between the methods of determining and estimating the chlorophyll contents. The grain yield per plant showed the highest values when using the 100 % mineral fertilizer source, with increments above 10 %, in relation to the other sources, spending US$ 89.77 on fertilizer and earning over US$ 538.60 on grain yield. There was a positive correlation between the photosynthetic pigments obtained by both methods and grain yield per plant. Both methods are recommended for the evaluation of chlorophyll concentrations.