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Scientia Agricola, Volume: 78, Número: 4, Publicado: 2021
  • Homogeneous zones of vegetation index for characterizing variability and site-specific management in vineyards Agricultural Engineering

    Oldoni, Henrique; Costa, Bruno Ricardo Silva; Bognola, Itamar Antônio; Souza, Claudia Rita de; Bassoi, Luís Henrique

    Resumo em Inglês:

    ABSTRACT Characterization of the spatial variability of vegetative vigor in vineyards can help improve the performance of site-specific management practices, or the management of vineyards with different rates. Characterization using canopy proximal sensing has been a widely disseminated technique; however, vineyards in southeastern Brazil, where the utilization of annual double pruning results in a winter harvest, knowledge of the role of variability in improving vineyard management has not yet been applied. This study aimed to determine if post-veraison mapping of a normalized difference vegetation index could be used to assess the variability in grapevine vigor, water status, physiology, yield and berry quality attributes at harvest in an irrigated vineyard in southeastern Brazil. This normalized difference vegetation index was measured with an active canopy sensor, and spatial distribution maps over two growing seasons of a vineyard, managed on an annual double pruning basis, were generated. Attributes of physiological and technological berry maturation, leaf water potential, gas exchange, production, and fresh pruning weight were calculated. These normalized difference vegetation index maps allowed for the determination of variability in vegetative vigor and the productive potential of the vineyard; however, high levels of rainfall during the maturation period may reduce the potential of using these maps for determining berry parameters.
  • Evapotranspiration mapping of commercial corn fields in Brazil using SAFER algorithm Agricultural Engineering

    Venancio, Luan Peroni; Mantovani, Everardo Chartuni; Amaral, Cibele Hummel do; Neale, Christopher Michael Usher; Filgueiras, Roberto; Gonçalves, Ivo Zution; Cunha, Fernando França da

    Resumo em Inglês:

    ABSTRACT SAFER (Simple Algorithm for Evapotranspiration Retrieving) is a relatively new algorithm applied successfully to estimate actual crop evapotranspiration (ET) at different spatial scales of different crops in Brazil. However, its use for monitoring irrigated crops is scarce and needs further investigation. This study assessed the performance of SAFER to estimate ET of irrigated corn in a Brazilian semiarid region. The study was conducted in São Desidério, Bahia State, Brazil, in corn-cropped areas in no-tillage systems and irrigated by central pivots. SAFER algorithm with original regression coefficients (a = 1.8 and b = –0.008) was initially tested during the growing seasons of 2014, 2015, and 2016. SAFER performed very poorly for estimating corn ET, with RMSD values greater than 1.18 mm d –1 for 12 fields analyzed and NSE values < 0 in most fields. To improve estimates, SAFER regression coefficients were calibrated (using 2014 and 2015 data) and validated with 2016 data, with the resulting coefficients a and b equal to 0.32 and –0.0013, respectively. SAFER performed well for ET estimation after calibration, with r 2 and NSE values equal to 0.91 and RMSD = 0.469 mm d –1 . SAFER also showed good performance (r 2 = 0.86) after validation, with the lowest RMSD (0.58 mm d –1 ) values for the set of 14 center pivots in this growing season. The results support the use of calibrated SAFER algorithm as a tool for estimating water consumption in irrigated corn fields in semiarid conditions.
  • Temperature influences swine wastewater treatment by aquatic plants Agricultural Engineering

    Weirich, Carlos Eduardo; Feiden, Aldi; Souza, Camila Silveira; Marchetti, Clarice Rossato; Aleixo, Valdemir; Klosowski, Élcio Silvério

    Resumo em Inglês:

    ABSTRACT Studies show that aquatic plants are an efficient alternative to minimize the harmful effects of wastewater. Two species of aquatic macrophytes (Pistia stratiotes and Eichhornia crassipes) were chosen to evaluate the temperature effect on the performance of these macrophytes species in a post-treatment system of swine wastewater. The experiment was carried out in the municipality of Toledo, Paraná State, Brazil. For the experimental system, 24 concrete tanks with 80 L capacity were used, each measuring approximately 1.5 m in length, 0.25 m in width and 0.16 m deep. Wastewater characteristics and variables hydrogen potential (pH), electrical conductivity (EC), and dissolved oxygen (DO) were measured weekly. After, we analyzed the aquatic macrophytes and centesimal composition. The use of aquatic macrophytes was efficient for final swine wastewater polishing. Nitrogen removal showed higher efficiency in the summer period for both species studied. The abiotic variables (pH and EC) presented better results during the winter for both species evaluated. Air and wastewater low temperatures did not influence these variables. Dissolved oxygen presented better results in the summer period for E. crassipes species. There was a significant increase in N and P contents in the plant tissue. This fact proves that the use of aquatic macrophytes is an interesting alternative for swine wastewater treatment.
  • Sequential feeding with diets varying in amino acid content for growing-finishing pigs Animal Science And Pastures

    Silva, Welex Cândido da; Campos, Paulo Henrique Reis Furtado; Santos, Luan Sousa dos; Veira, Alini Mari; Fraga, Alícia Zem; Hauschild, Luciano

    Resumo em Inglês:

    ABSTRACT This study aimed to evaluate the effects of daily phase feeding (DP) and sequential feeding (SEQ) on the feeding behavior, performance, and body composition of growing-finishing pigs. Sixty barrows at 29.7 ± 2.8 kg body weight (BW) were assigned to one of four treatments: DP with a blended proportion of feeds A (high nutrient density) and B (low nutrient density) was adjusted to match 100 % of daily amino acid (AA) diet recommendations (DP100); a negative treatment, which matched 70 % of daily AA diet recommendations (DP70); and two SEQ with a blend of feeds A and B, adjusted twice a day (at 00h00 and 12h00), to match 70 or 110 % of daily AA diet recommendations during two 12 h intervals: SEQ110-70 and SEQ70-110. DP70 and SEQ showed a lower feed consumption rate compared to DP100 (p < 0.05). Compare to DP100, pigs in both SEQ programs had a similar average daily feed intake (ADFI), average daily gain (ADG), feed efficiency ratio (G:F) and body fat and lean mass ( p > 0.05). SEQ110-70 and SEQ70-110 showed similar ADFI, ADG, G:F and body lean mass (p > 0.05). However, fat gain was greater in SEQ110-70 than in SEQ70-110 (p < 0.05). Overall, the SEQ program does not improve performance and body composition. Furthermore, feeding pigs a diet with a higher AA level during the first 12 h of the day and a lower AA level during the remainder of the day increases fat deposition.
  • Low doses of monensin for lambs fed diets containing high level of ground flint corn Animal Science And Pastures

    Polizel, Daniel Montanher; Martins, André Storti; Miszura, Alexandre Arantes; Ferraz Júnior, Marcos Vinícius de Castro; Bertoloni, Analisa Vasques; Oliveira, Gabriela Bagio; Barroso, José Paulo Roman; Ferreira, Evandro Maia; Pires, Alexandre Vaz

    Resumo em Inglês:

    ABSTRACT Two experiments were proposed to evaluate the addition of monensin for lambs fed diets containing a high level of mature ground flint corn. The experimental diets were as follows: no inclusion of monensin (M0) and inclusion of 8 (M8), 16 (M16) and 24 mg kg–1 of monensin (M24). In experiment 1, eight cannulated wethers were divided into a double 4 × 4 Latin square experimental design to evaluate nutrient digestibility, plasma parameters and rumen fermentation. The experiment lasted 112 days, divided into four periods of 28 days each. In experiment 2, ninety-two lambs were used in a randomized block design to evaluate the performance over 56 days. In experiment 1, doses of monensin had no effect on nutrient intake (p ≥ 0.07) and digestibility (p ≥ 0.09). There was a quadratic effect for acetate molar proportion (p = 0.01), acetate to propionate ratio (p = 0.04) and rumen pH (p < 0.01). However, there was no effect on the molar proportion of propionate and butyrate. The monensin decreased linearly the total SCFA concentration (p < 0.01). The inclusion of monensin increased glucose (p < 0.01) and decreased lactate concentration in plasma (p = 0.05). In experiment 2, monensin decreased dry matter intake (p = 0.04). However, there was a quadratic effect for average daily gain (p = 0.03) and feed efficiency (p < 0.01), with the greatest values observed for the M8 diet. Thus, the inclusion of 8 mg kg–1 of dry matter diet (DM) improves ruminal fermentation and plasma parameters, resulting in greater growth performance in lambs.
  • Acylated anthocyanins from organic purple-fleshed sweet potato (Ipomoea batatas (L.) Lam) produced in Brazil Food Science And Technology

    Jesus, Monalisa Santana Coelho de; Santiago, Manuela Cristina Pessanha de Araújo; Pacheco, Sidney; Gouvêa, Ana Cristina Miranda Senna; Nascimento, Luzimar da Silva de Mattos do; Borguini, Renata Galhardo; Guerra, José Guilherme Marinho; Espindola, José Antonio Azevedo; Godoy, Ronoel Luiz de Oliveira

    Resumo em Inglês:

    ABSTRACT Acylated anthocyanins from a purple-fleshed sweet potato (PFSP), obtained by organic cultivation in Brazil, were characterized after separation by a high performance liquid chromatography-diode array detector (HPLC-PDA). These anthocyanins were manually collected at the detector output, concentrated and injected into a high resolution mass spectrometer (ESI-QTOF-MS2). Twenty-two acylated anthocyanins were detected. Among them, sixteen had been reported in the literature and six, derived from peonidin were reported for the first time in sweet potato roots in this study. These compounds showed molecular ions with accurate mass/charge ratios (m/z) of 909.2081, 961.3010, 961.2571, 963.3345, 1123.2932 and 1179.3862. Although anthocyanins in PFSP have already been extensively studied, the variety studied in this work is probably genetically different from all varieties and cultivars already researched, which would explain why these anthocyanins have not been observed in the previously studied varieties.
  • Comparison of ethylene carbonate and formamide as components of the hybridization mixture in FISH Genetics And Plant Breeding

    Kalinka, Anna; Myśliwy, Monika; Achrem, Magdalena

    Resumo em Inglês:

    ABSTRACT The protocols for in situ hybridization (ISH) techniques can vary considerably; however, they usually include denaturation and hybridization steps. Denaturing compounds are used to reduce denaturation and hybridization temperature, which keeps the proper morphology of the preparation. Formamide is the most commonly used reagent in in situ hybridization to lower the melting temperature. The substitution of toxic formamide for a non-toxic ethylene carbonate at 20 % and 50 % concentration in the hybridization mixture helped obtain a high quality in situ hybridization result with two sequences characteristic for rye, JNK, and Bilby. The results after hybridization, with a duration of 90 min and 16 h, were identical when formamide or ethylene carbonate were used in the mixture. In addition, the toxic formamide was eliminated from the post-hybridization steps and specific hybridization signals for both probes were still obtained.
  • Genomic prediction of leaf rust resistance to Arabica coffee using machine learning algorithms Genetics And Plant Breeding

    Sousa, Ithalo Coelho de; Nascimento, Moysés; Silva, Gabi Nunes; Nascimento, Ana Carolina Campana; Cruz, Cosme Damião; Silva, Fabyano Fonseca e; Almeida, Dênia Pires de; Pestana, Kátia Nogueira; Azevedo, Camila Ferreira; Zambolim, Laércio; Caixeta, Eveline Teixeira

    Resumo em Inglês:

    ABSTRACT Genomic selection (GS) emphasizes the simultaneous prediction of the genetic effects of thousands of scattered markers over the genome. Several statistical methodologies have been used in GS for the prediction of genetic merit. In general, such methodologies require certain assumptions about the data, such as the normality of the distribution of phenotypic values. To circumvent the non-normality of phenotypic values, the literature suggests the use of Bayesian Generalized Linear Regression (GBLASSO). Another alternative is the models based on machine learning, represented by methodologies such as Artificial Neural Networks (ANN), Decision Trees (DT) and related possible refinements such as Bagging, Random Forest and Boosting. This study aimed to use DT and its refinements for predicting resistance to orange rust in Arabica coffee. Additionally, DT and its refinements were used to identify the importance of markers related to the characteristic of interest. The results were compared with those from GBLASSO and ANN. Data on coffee rust resistance of 245 Arabica coffee plants genotyped for 137 markers were used. The DT refinements presented equal or inferior values of Apparent Error Rate compared to those obtained by DT, GBLASSO, and ANN. Moreover, DT refinements were able to identify important markers for the characteristic of interest. Out of 14 of the most important markers analyzed in each methodology, 9.3 markers on average were in regions of quantitative trait loci (QTLs) related to resistance to disease listed in the literature.
  • Sombric-like horizon and xanthization in polychrome subtropical soils from Southern Brazil: implications for soil classification Soils And Plant Nutrition

    Chiapini, Mariane; Oliveira Junior, Jairo Calderari de; Schellekens, Judith; Almeida, Jaime Antonio de; Buurman, Peter; Vidal-Torrado, Pablo

    Resumo em Inglês:

    ABSTRACT The occurrence of dark subsurface horizons rich in organic matter (OM) associated with polychrome in the B horizon (yellowish over reddish hue) is common in soils from Southern Brazil. The formation of these horizons and the combination with such morphological attributes has not been properly documented, and neither has the cause effect relationship. Four soil profiles with such sombric-like horizons with a yellowish color at the upper part of the B horizon over red subsoil were studied in Southern Brazil. Results from micromorphology, extractable sesquioxide minerals, clay mineralogy and isomorphic substitution of Fe by Al in iron minerals showed that melanization, xanthization, bioturbation, moderate shrinking/swelling and moderate ferralitization were the most evident pedogenetic processes in role. Xanthization is closely related to the sombric-like horizon formation. In the studied area the findings demonstrated that no clay and OM illuviation had taken place. Therefore, the classification of these soils was revisited, so as to take into account the processes that underlie their genesis with emphasis on xanthization, clay illuviation and soil aggregation. The results suggest that the sombric horizon may need redefinition, unless profiles can be found in which illuviation of clay and/or OM can be proven.
  • Replacing the (inefficient) manual runoff sampling method used in Brazil – a prototype sample splitter Soils And Plant Nutrition

    Samuel-Rosa, Alessandro; Moura-Bueno, Jean Michel; Dalmolin, Ricardo Simão Diniz

    Resumo em Inglês:

    ABSTRACT The method used to sample the runoff collected from soil erosion plots can be a significant source of error. In this study, we performed a laboratory experiment to evaluate the efficiency of the runoff sampling method most commonly used in Brazil. It is based on the manual homogenization and sampling of the collected runoff. Using soil material with 583 g kg–1 of sand and 89 g kg–1 of clay, the manual sampling method was tested for its ability to produce representative samples of artificial suspensions with a concentration of 2, 10 and 50 g L–1 of total solids. An underestimation of 30 % or more of the concentration of total solids was observed, with a variation of the same magnitude (CV between 20 and 45 %). We then developed a prototype sample splitter to replace the manual sampling method and tested it using the same artificial suspensions. The splitter was efficient in producing samples representative of the artificial suspensions, even without altering the particle size distribution of the total solids. Both absolute percentage errors (|< 5 %|) and the variation between five replicates (CV < 3 %) were small. The problems with the manual method are due to the inefficient homogenization that facilitates the differential sedimentation of particles of different sizes. If these problems are also found in other areas, then the prototype that we developed is a reasonable alternative.
  • Processing Eucalyptus cloeziana seed lots to improve purity, germination and vigor Note

    Michelon, Thomas Bruno; Vieira, Elisa Serra Negra; Panobianco, Maristela

    Resumo em Inglês:

    ABSTRACT Eucalyptus cloeziana is one of the highest-density wood species offering significant added value, frequently used in the construction and furniture industries. Despite its suitability, it may be overlooked on account of its propagation difficulties due either to its low rooting cutting capacity or to its seeds having a low germination rate perhaps attributable to the high proportion of indistinguishable impurities within the seed lots. This study aimed to develop an efficient technique for Eucalyptus cloeziana seed processing to increase the physical purity and, consequently, the physiological quality of the seed lot. Three seed lots, separated by size in sieves with 1.18, 1.00, and 0.84 mm square openings, were used. X-ray analyses were carried out, the number of normal seedlings and germination rate identified and the percentage and speed of seedling emergence under greenhouse conditions ascertained. The greenhouse evaluation showed that the seed retained in the 1.18 mm sieve presented viability and vigor twice that of the control. Therefore, the processing technique by size classification is efficient in terms of improving the physical and physiological performance of Eucalyptus cloeziana seed lots.
  • A short review: Comparisons of high-throughput phenotyping methods for detecting drought tolerance Review

    Kim, Jaeyoung; Kim, Ki-Seung; Kim, Yoonha; Chung, Yong Suk

    Resumo em Inglês:

    ABSTRACT Drought is a major threat worldwide for crop production, especially due to the rapid climate changes. Current drought solutions involve improving irrigation system, rainwater harvesting, damming, cloud seeding, and changes of cultivation methods. Despite effective, each solution has economic, environmental, and temporal drawbacks. Among all solutions, the most effective, inexpensive and manageable method is the use of drought-tolerant cultivars via plant breeding. However, conventional plant breeding is a time-consuming and laborious task, especially for phenotypic data acquisition of target traits of numerous progenies. High-throughput phenotyping (HTP) is a recently developed method and has potential to overcome the mentioned issues. HTP offers massive, accurate, rapid, and automatic data acquisition in the breeding procedure and can be a breakthrough for developing drought resistant/tolerant cultivars. This study introduces various methods of HTP to detect drought stress, which can accelerate the breeding processes of drought-tolerant cultivars to provide helpful guidelines for breeders and researchers to choose appropriate methods.
  • Erratum Erratum

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