cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14278359.v1
title: Polyol-ester impact on boron foliar absorption and remobilization in cotton and coffee trees

description: ABSTRACT Foliar fertilization can be recommended to treat boron (B) deficiency in coffee and cotton. Considering that B foliar fertilizers with polyol-boron complexes can affect B uptake and mobility differently within the plant, and coffee and cotton have different cuticles and stomata density, a differential response would be expected. We aimed to study the foliar application of boric acid combined with sorbitol on B uptake and translocation in cotton and coffee. Green-house grown plants received B as boric acid and a sorbitol-monoethanolamine complex and were sampled up to 96 h after application. Boron absorption was fast, reaching 60 and 80 % in cotton and coffee 96 h after application, respectively. Uptake rates and total B absorption were similar for the fertilizers. The proportion of B taken up by coffee is greater than by cotton likely because of the greater stomata density in coffee and less likely due to the higher amount of wax in cotton cuticle. Boron remobilization is higher in coffee as compared with cotton. Sorbitol seems to increase B transport in the transpiratory stream of cotton, but impairs remobilization in the phloem since B translocation to roots is decreased in both cotton and coffee.
DOI: 10.6084/m9.figshare.14278361.v1
title: Universality of Kenworthy and DRIS norms for prata and cavendish bananas grown in two environments

description: ABSTRACT Tissue analysis results are interpreted by comparing them with nutrient standards; however, using universal standards may lead to a misleading nutritional diagnosis. This study aimed to evaluate the degree of universality of Kenworthy and DRIS norms for irrigated ‘Prata-Anã’ (AAB) and ‘Grande Naine’ (AAA) banana plants grown in two environments. The study was carried out using a database containing leaf nutrient contents and yield data of two farms located in Ponto Novo, Bahia State, and Missão Velha, Ceará State, Brazil. A reference population was that with yields above the average yield plus 0.5 standard deviation. Using a reference population, the mean, standard deviation, and coefficient of variation of nutrient content and dual nutrient ratios were calculated for each site × cultivar combination. To verify the homogeneity of variance among populations, F-test was used (p≤0.05). Means were compared using t-test (p≤0.05). Differences in climate and soil at each farm explain the high frequency of significant differences found between norms for each site. Kenworthy norms established for interpreting leaf nutrient contents of P, K, Ca, Mg, S, Cu, Fe, Mn, and Zn for ‘Prata-Anã’ grown in Ceará were higher than those in Bahia, while for N and B contents, the norms were higher in Bahia. This is due to differences in soil fertility and alkalinity affecting nutrient availability as well as non-nutritional factors. Kenworthy and DRIS norms for ‘Prata-Anã’ and ‘Grande Naine’ bananas grown in Ceará have higher variability and are greater than for those grown in Bahia. Norms are less convergent for ‘Prata-Anã’ than ‘Grande Naine’. Site- and cultivar-specific norms are recommended over universal ones for assessing the nutritional status of ‘Prata-Anã’ and ‘Grande Naine’ banana plants cultivated in different environments.
DOI: 10.6084/m9.figshare.14278362
title: Phytomass input and nutrient cycling under different management systems in dwarf cashew cultivation

description: ABSTRACT Rational management of spontaneous plants is an alternative for increasing productivity in tree crops. This study aimed to evaluate the impact of management systems between rows and under the canopy of early dwarf cashew trees on the soil chemical properties and light-fraction organic matter and cashew root systems; we also evaluated the nutrient inputs from the spontaneous plants phytomass and cashew leaves deposited on an Arenic Kandiustults. The management systems under study were disc harrowing (DH) and mechanical mowing (MM) between rows, both with clearing under the cashew canopy (crowning), and herbicide (HERB) between the rows and under the canopy (without crowning). Soil and plant samples (leaves, stems, and roots) were collected at three points: under the canopy, at the canopy projected limit, and between the rows of cashew plants, all after seven years of conducting the experiment. Soil samples collected at the layers of 0.00-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m were evaluated for total organic carbon, light-fraction organic matter, and chemical attributes. Dry matter, Na, Ca, Mg, N, P, and K were determined in the spontaneous-plant phytomass from under the canopy, at the canopy projected limit, and between the rows. Results showed that between rows of cashew trees there are higher phytomass input and increases in the light fraction of organic matter, pH and Mg2+ in the soil in the treatment MM. Not removing crop residues or spontaneous plants by crowning promoted accumulation of organic material and higher contents of nutrients under the canopy. The management of spontaneous plants and also soil surface under the canopy of the cashew plants had a great influence on productivity. The crowning, used in MM and DH, led to lower productivity, 1,171.87 and 594.97 kg ha-1, respectively, when compared with the absence of crowning (HERB), which resulted in productivity of 1,363.80 kg ha-1. The practice of crowning is not recommended for soil management systems in dwarf cashew crops.
DOI: 10.6084/m9.figshare.14278362.v1
title: Phytomass input and nutrient cycling under different management systems in dwarf cashew cultivation

description: ABSTRACT Rational management of spontaneous plants is an alternative for increasing productivity in tree crops. This study aimed to evaluate the impact of management systems between rows and under the canopy of early dwarf cashew trees on the soil chemical properties and light-fraction organic matter and cashew root systems; we also evaluated the nutrient inputs from the spontaneous plants phytomass and cashew leaves deposited on an Arenic Kandiustults. The management systems under study were disc harrowing (DH) and mechanical mowing (MM) between rows, both with clearing under the cashew canopy (crowning), and herbicide (HERB) between the rows and under the canopy (without crowning). Soil and plant samples (leaves, stems, and roots) were collected at three points: under the canopy, at the canopy projected limit, and between the rows of cashew plants, all after seven years of conducting the experiment. Soil samples collected at the layers of 0.00-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m were evaluated for total organic carbon, light-fraction organic matter, and chemical attributes. Dry matter, Na, Ca, Mg, N, P, and K were determined in the spontaneous-plant phytomass from under the canopy, at the canopy projected limit, and between the rows. Results showed that between rows of cashew trees there are higher phytomass input and increases in the light fraction of organic matter, pH and Mg2+ in the soil in the treatment MM. Not removing crop residues or spontaneous plants by crowning promoted accumulation of organic material and higher contents of nutrients under the canopy. The management of spontaneous plants and also soil surface under the canopy of the cashew plants had a great influence on productivity. The crowning, used in MM and DH, led to lower productivity, 1,171.87 and 594.97 kg ha-1, respectively, when compared with the absence of crowning (HERB), which resulted in productivity of 1,363.80 kg ha-1. The practice of crowning is not recommended for soil management systems in dwarf cashew crops.
DOI: 10.6084/m9.figshare.14278365
title: Outstanding impact of Azospirillum brasilense strains Ab-V5 and Ab-V6 on the Brazilian agriculture: Lessons that farmers are receptive to adopt new microbial inoculants

description: ABSTRACT For decades, researchers around the world search for strategies aiming at higher sustainability in agriculture. The microbial inoculants or biofertilizers are biotechnological products used for different purposes, the main one being to totally or partially replace chemical fertilizers, with an emphasis on N-fertilizers, reducing costs of production and decreasing the contamination of the soil, water, and atmosphere. Depending on the microorganism and the inoculated crop, inoculants can also induce plant protection to abiotic and biotic stresses and positively modify their physiology. Although inoculation studies and the use of inoculants by farmers date more than a century ago, they have gained more notoriety in the past decade. Brazil has a long tradition in the use of rhizobial inoculants, especially for the soybean crop, but it was only in 2009 that the first commercial inoculant carrying the plant-growth-promoting Azospirillum brasilense strains Ab-V5 (=CNPSo 2083) and Ab-V6 (=CNPSo 2084), identified by our research group, reached the market. One decade after the release of these two strains, 10.5 million doses were commercialized for grasses, including corn, wheat, rice, and pastures of brachiarias, and co-inoculation of legumes, such as soybean and common bean. Several research groups in Brazil presented impressive results of increases in root growth, biomass production, grain yield, uptake of nutrients and water, and increased tolerance to abiotic stresses due to the inoculation with Ab-V5 and Ab-V6. In this review, we gathered the results obtained so far in one decade with these two strains in several grasses and legume crops, confirming their versatility and indicating that with convincing, reliable, and consistent results, the Brazilian farmers are receptive to the adoption of new sustainable technologies based on microorganisms.
DOI: 10.6084/m9.figshare.14278365.v1
title: Outstanding impact of Azospirillum brasilense strains Ab-V5 and Ab-V6 on the Brazilian agriculture: Lessons that farmers are receptive to adopt new microbial inoculants

description: ABSTRACT For decades, researchers around the world search for strategies aiming at higher sustainability in agriculture. The microbial inoculants or biofertilizers are biotechnological products used for different purposes, the main one being to totally or partially replace chemical fertilizers, with an emphasis on N-fertilizers, reducing costs of production and decreasing the contamination of the soil, water, and atmosphere. Depending on the microorganism and the inoculated crop, inoculants can also induce plant protection to abiotic and biotic stresses and positively modify their physiology. Although inoculation studies and the use of inoculants by farmers date more than a century ago, they have gained more notoriety in the past decade. Brazil has a long tradition in the use of rhizobial inoculants, especially for the soybean crop, but it was only in 2009 that the first commercial inoculant carrying the plant-growth-promoting Azospirillum brasilense strains Ab-V5 (=CNPSo 2083) and Ab-V6 (=CNPSo 2084), identified by our research group, reached the market. One decade after the release of these two strains, 10.5 million doses were commercialized for grasses, including corn, wheat, rice, and pastures of brachiarias, and co-inoculation of legumes, such as soybean and common bean. Several research groups in Brazil presented impressive results of increases in root growth, biomass production, grain yield, uptake of nutrients and water, and increased tolerance to abiotic stresses due to the inoculation with Ab-V5 and Ab-V6. In this review, we gathered the results obtained so far in one decade with these two strains in several grasses and legume crops, confirming their versatility and indicating that with convincing, reliable, and consistent results, the Brazilian farmers are receptive to the adoption of new sustainable technologies based on microorganisms.
DOI: 10.6084/m9.figshare.14268284
title: Soil spectral library of Piauí State using machine learning for laboratory analysis in Northeastern Brazil

description: ABSTRACT Soil chemical and physical analyses are the major sources of data for agriculture. However, traditional soil analyses are time-consuming, not cost-efficient, and not environmentally friendly. An alternative to traditional soil analyses is soil spectroscopy. This technique is a low-cost and quick analytical method, which can be implemented in a laboratory and/or in-situ. Nevertheless, some spectrometers are expensive and do not contemplate the entire spectrum. Despite this limitation, the main objective of the study was to create a soil spectral library of the Piauí State using only the 1000–2500 nm range. In this sense, it was evaluated and standardized the soil spectral library by accessing the combination of smoothing, standard normal variate, continuum removal, and Savitzky-Golay derivative spectral preprocessing procedures with partial least squares, random forest, and cubist machine learning algorithms. It was collected 262 geo-referenced soil samples at the layer of 0.00–0.20 m across the entire Piauí State, representing most of its soil variability. The soil properties evaluated were pH(H2O), sand, clay, and soil organic carbon (SOC) contents. This study demonstrated that the Standard Normal Variate was one of the most promising preprocessing procedures to improve model predictions for pH(H2O), sand, and clay. For SOC and pH, the best overall results were without preprocessing the soil spectra. Moreover, the cubist model was the most accurate in predicting soil properties. Finally, our study showed evidence of the potential and feasibility of using this soil spectral library to estimate soil properties such as pH(H2O), sand, clay, and SOC.
DOI: 10.6084/m9.figshare.14278367
title: Clonal teak litter in tropical soil: decomposition, nutrient cycling, and biochemical composition

description: ABSTRACT: Litter decomposition dynamics and nutrient release are also dependent on their biochemical composition, and such information is important for adequate nutritional management but is still incipient for plants like teak. This study aimed to evaluate the decomposition dynamics, nutrient release, and biochemical composition of clonal teak litter. The study was conducted in areas of clonal teak stands, in São José do Rio Claro, Mato Grosso, Brazil. Litter collectors were arranged in the area to collect material along the entire dry period. Subsequently, this litter was placed in litter bags, which were distributed in the area. The litter bags were collected every month, for 0.91 years, to determine the dry matter and mineral nutrient contents, in order to estimate the decomposition and nutrient release. Litter biochemical composition was determined at the times of 0, 0.25, 0.58, 0.75, and 0.91 years. Teak litter, essentially leaves, had a half-life time (t1/2) of dry matter and C of 0.74 years, due to the high content of insoluble lignin, which corresponds to 2.28 Mg ha-1 of dry matter and 1.2 Mg ha-1 of C. The t1/2 values of N and P release (1.20 and 1.01 years) were higher than those of K, Ca, and Mg (0.08, 0.47, and 0.66 years, respectively). Hence, the nutrient release rate of the litter followed the descending order: K &gt; Ca &gt; Mg &gt; P &gt; N. The litter biochemical composition at the end of the experimental period showed reductions of 18.7 % in polysaccharides and holocellulose, 56 % in polyphenols, 56.3 % in tannins, 22.2 % in extractives, and 28.5 % in soluble lignin; and increases of 25.6 % in insoluble lignin and 22.6 % in total lignin. These data are useful for the balance of carbon and mineral nutrients and to support fertilization management in teak plantations in low-fertility soils.
DOI: 10.6084/m9.figshare.14278368
title: Different N-fertilization sources affecting the native soil organic matter mineralization on Technosols under iron ore tailing

description: ABSTRACT: Accidents related to the rupture of iron ore tailings dams have dramatically impacted on the Brazilian natural ecosystem. So, the development of strategies to recover soil organic matter levels and build-up Technosols are required. This study aimed to evaluate the effect of N-mineral and -organic fertilization and the rhizospheric effect on soil organic matter mineralization from Technosols built under iron ore tailings. The experiment was carried out in a greenhouse; we used a factorial scheme 2 × 2 × 3: without and with the plant Crotalaria juncea ; without and with mineral fertilization; and three different organic fertilization (without organic fertilization, sewage sludge, and household waste composting), with four randomized blocks. The experimental units were PVC columns installed with a top layer of iron ore tailing from a dam, where gases were sampled to determine the CO2-C, CH4-C concentrations, and CO2-δ13C. The organic fertilization promoted a positive priming effect of 184 %. However, with mineral fertilization, no effect was observed in soil derived-CO2-C accumulated and priming effect. Similarly to non-planted soil, the planted soils with mineral and organic fertilization promoted a steady reduction in soil derived-CO2-C accumulated and rhizosphere priming effect. The soil with mineral fertilization improved in 5.52 and 0.45 g per column the shoot and root dry matter of Crotalaria when compared to the soil without mineral fertilization. In summary, the organic fertilization in Technosols built over iron ore tailings dams during revegetation was not enough to ensure the plant development and preservation of soil organic matter. However, the combination of mineral and organic fertilization promoted negative rhizosphere priming effect and a significant increase in plant biomass.
DOI: 10.6084/m9.figshare.14268284.v1
title: Soil spectral library of Piauí State using machine learning for laboratory analysis in Northeastern Brazil

description: ABSTRACT Soil chemical and physical analyses are the major sources of data for agriculture. However, traditional soil analyses are time-consuming, not cost-efficient, and not environmentally friendly. An alternative to traditional soil analyses is soil spectroscopy. This technique is a low-cost and quick analytical method, which can be implemented in a laboratory and/or in-situ. Nevertheless, some spectrometers are expensive and do not contemplate the entire spectrum. Despite this limitation, the main objective of the study was to create a soil spectral library of the Piauí State using only the 1000–2500 nm range. In this sense, it was evaluated and standardized the soil spectral library by accessing the combination of smoothing, standard normal variate, continuum removal, and Savitzky-Golay derivative spectral preprocessing procedures with partial least squares, random forest, and cubist machine learning algorithms. It was collected 262 geo-referenced soil samples at the layer of 0.00–0.20 m across the entire Piauí State, representing most of its soil variability. The soil properties evaluated were pH(H2O), sand, clay, and soil organic carbon (SOC) contents. This study demonstrated that the Standard Normal Variate was one of the most promising preprocessing procedures to improve model predictions for pH(H2O), sand, and clay. For SOC and pH, the best overall results were without preprocessing the soil spectra. Moreover, the cubist model was the most accurate in predicting soil properties. Finally, our study showed evidence of the potential and feasibility of using this soil spectral library to estimate soil properties such as pH(H2O), sand, clay, and SOC.
DOI: 10.6084/m9.figshare.14278367.v1
title: Clonal teak litter in tropical soil: decomposition, nutrient cycling, and biochemical composition

description: ABSTRACT: Litter decomposition dynamics and nutrient release are also dependent on their biochemical composition, and such information is important for adequate nutritional management but is still incipient for plants like teak. This study aimed to evaluate the decomposition dynamics, nutrient release, and biochemical composition of clonal teak litter. The study was conducted in areas of clonal teak stands, in São José do Rio Claro, Mato Grosso, Brazil. Litter collectors were arranged in the area to collect material along the entire dry period. Subsequently, this litter was placed in litter bags, which were distributed in the area. The litter bags were collected every month, for 0.91 years, to determine the dry matter and mineral nutrient contents, in order to estimate the decomposition and nutrient release. Litter biochemical composition was determined at the times of 0, 0.25, 0.58, 0.75, and 0.91 years. Teak litter, essentially leaves, had a half-life time (t1/2) of dry matter and C of 0.74 years, due to the high content of insoluble lignin, which corresponds to 2.28 Mg ha-1 of dry matter and 1.2 Mg ha-1 of C. The t1/2 values of N and P release (1.20 and 1.01 years) were higher than those of K, Ca, and Mg (0.08, 0.47, and 0.66 years, respectively). Hence, the nutrient release rate of the litter followed the descending order: K &gt; Ca &gt; Mg &gt; P &gt; N. The litter biochemical composition at the end of the experimental period showed reductions of 18.7 % in polysaccharides and holocellulose, 56 % in polyphenols, 56.3 % in tannins, 22.2 % in extractives, and 28.5 % in soluble lignin; and increases of 25.6 % in insoluble lignin and 22.6 % in total lignin. These data are useful for the balance of carbon and mineral nutrients and to support fertilization management in teak plantations in low-fertility soils.
DOI: 10.6084/m9.figshare.14278371
title: Improving indirect measurements of the leaf area index using canopy height

description: Abstract: The objective of this work was to evaluate the use of plant height as a calibration variable for improving indirect measurements of the leaf area index (LAI). Three experiments were conducted with different crops - corn (Zea mays), soybean (Glycine max), and sugarcane (Saccharum officinarum) -, to compare the performance of the LAI measured indirectly (LAIind) and corrected by the calibration variable with the LAI measured directly (LAIref). Without the proposed correction, the LAIind tended to be overestimated by 20%, on average, compared with the LAIref, for the three crops. After crop height was used to adjust the LAIind, a strong positive relationship was observed between the LAIref and the corrected LAIind (R2 = 0.96); overestimation was reduced to 4% and the root-mean-square error decreased to 0.35 m2 m-2. The variable canopy height is promising for the correction of the LAI of the soybean, corn, and sugarcane crops.
DOI: 10.6084/m9.figshare.14278371.v1
title: Improving indirect measurements of the leaf area index using canopy height

description: Abstract: The objective of this work was to evaluate the use of plant height as a calibration variable for improving indirect measurements of the leaf area index (LAI). Three experiments were conducted with different crops - corn (Zea mays), soybean (Glycine max), and sugarcane (Saccharum officinarum) -, to compare the performance of the LAI measured indirectly (LAIind) and corrected by the calibration variable with the LAI measured directly (LAIref). Without the proposed correction, the LAIind tended to be overestimated by 20%, on average, compared with the LAIref, for the three crops. After crop height was used to adjust the LAIind, a strong positive relationship was observed between the LAIref and the corrected LAIind (R2 = 0.96); overestimation was reduced to 4% and the root-mean-square error decreased to 0.35 m2 m-2. The variable canopy height is promising for the correction of the LAI of the soybean, corn, and sugarcane crops.