Leaf Analysis
Mostrando 1-12 de 1156 artigos, teses e dissertações.
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1. Extracts of the Native Brazilian Tree Garcinia gardneriana Inhibit Urediniospore Germination of Coffee Leaf Rust Fungus
The fungal Hemileia vastatrix is the causal agent of coffee leaf rust, one of the worst and devastating disease in coffee cultures worldwide. As a result of our research on natural products for the development of novel agrochemicals, we found that the hexane extract from leaves of the Brazilian medicinal plant Garcinia gardneriana, at 500 μg mL-1, inhibited
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Linear relationships between biometric variables in lettuce seedlings
ABSTRACT Seedling production is an important step in growing vegetables. The study of relationships between variables has applications in practically all areas of study and is useful in identifying relationships among quality variables in vegetable seedlings. Thus, this work aims to estimate linear relationships between biometric variables in lettuce seedlin
Revista Ceres. Publicado em: 2022
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3. Rapid Recognizing the Producing Area of a Tobacco Leaf Using Near-Infrared Technology and a Multi-Layer Extreme Learning Machine Algorithm
A novel recognition method was put forward to identify the producing areas of the flue-cured tobacco leaves rapidly and non-destructively by using a near-infrared (NIR) spectrometer and a multi-layer-extreme learning machine (ML-ELM) algorithm. In contrast to traditional linear discriminant analysis (LDA) and extreme learning machine (ELM) algorithms, the ac
Journal of the Brazilian Chemical Society. Publicado em: 2022
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4. METABOLIC PROFILING AND CYTOTOXIC ACTIVITY OF METHANOL EXTRACTS FROM CHAMAECRISTA DUCKEANA (P. BEZERRA & A. FERN.) H. S. IRWIN & BARNEBY (LEGUMINOSAE, CAESALPINIOIDEAE)
The genus Chamaecrista comprises more than 330 species, with only a few studies on their chemical composition and biologic activities. In this study, the phytochemical profile of leaf, stems, and fruits extracts of the C. duckeana were examined by UPLC ESI HRMS analysis to determine possibly bioactive constituents. The antioxidant activity was carried out th
Química Nova. Publicado em: 2022
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5. Phytocomponents, Evaluation of Anticholinesterase Activity and Toxicity of Hydroethanolic Extracts of Parkia platycephala Benth.
This study evaluated the chemical composition, antioxidant and anticholinesterase activities, and the toxicity of hydroethanolic extracts of the Parkia platycephala Benth. Hot extraction with 70% hydroethanolic solution was used to obtain crude extracts of the leaf (LE), bark (BE), flower (FE), and seed (SE). Separation and identification of the compounds we
Journal of the Brazilian Chemical Society. Publicado em: 2022
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6. PREDICTIVE MODELS OF CHLOROPHYLL CONTENT IN SUGARCANE SEEDLINGS USING SPECTRAL IMAGES
ABSTRACT Chlorophyll content is a widely used parameter for nutritional status diagnosis in sugarcane. This study aimed to develop a predictive model of chlorophyll content in sugarcane seedlings using spectral imagery analysis within the electromagnetic spectrum visible range. The experiment was carried out in a split-plot design, with two fertilization rat
Eng. Agríc.. Publicado em: 2021-08
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7. Polyphenol Profile and Quantitative Assessment of the Flavonoid Kaempferitrin in Wild and Cultivated Brazilian Amazonian Uncaria guianensis (Rubiaceae)
The Amazonian Rubiaceae species Uncaria guianensis (UG) is locally used as anti-inflammatory, antitumor, antidiabetic, anti-ulcers, and others. The phenolic content of its leaves is characterized by the great predominance of the flavonoid kaempferol-3,7-O-(α)-L-dirhamnoside (kaempferitrin). The present study quantitatively evaluates the kaempferitrin conten
J. Braz. Chem. Soc.. Publicado em: 2021-08
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8. CONTRIBUTION OF SOIL ATTRIBUTES AND MORPHOLOGICAL VARIABLES TO YIELD OF IRRIGATED GARLIC
ABSTRACT This study aimed to investigate relationships between the soil attributes that most affect garlic yield, which can be useful to choose a new area for the growing of this vegetable. We also aimed to study the effects of irrigation deficit at bulb formation stage (cloves) on final garlic quality and yield. The variables evaluated were garlic yield, ir
Eng. Agríc.. Publicado em: 2021-04
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9. Development and Validation of a Gas Chromatographic Method for the Quantification of Minor Alkaloids in Cocaine
The quantification of minor alkaloids in seized cocaine can provide information for drug profiling and law enforcement initiatives. This work presents the development and validation of an analytical method to quantitate minor alkaloids in cocaine samples using gas chromatography with flame ionization detector, after derivatization. The method was validated i
J. Braz. Chem. Soc.. Publicado em: 2021-04
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10. Evaluation of the Seasonality and Extraction Method on the Polar Extracts of Croton grewioides Baill. by Chromatogram Fingerprinting and Isolation of a New Triglycosylated Flavonoid
Croton grewioides Baill. popularly known as “canelinha” or “canelinha-de-cheiro” has been used for the treatment of influenza, antitussive, febrifuge and headache; however, the study of its phytochemical composition is limited. The aim of this study was to investigate the effect of the extraction method and seasonality through leaf extracts of four a
J. Braz. Chem. Soc.. Publicado em: 2021-02
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11. Odontadenia lutea (Apocynaceae) LEAVES: PHYTOCHEMICAL STUDY AND INSECTICIDAL ACTIVITY AGAINST LEAF-CUTTING ANTS Atta sexdens rubropilosa Forel
The present work describes the chemical constituents of Odontadenia lutea (Vell.) Markgr. leaves and the toxicities of its extract and fractions against Atta sexdens rubropilosa Forel (Hymenoptera: Formicidae). Chromatographic procedures of the ethanolic extract resulted in the identification of the triterpene β-amyrin, the flavonoid rutin, two fatty acids
Quím. Nova. Publicado em: 2021-01
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12. SPATIAL VARIABILITY IN LEAF ANALYSIS AND PRODUCTIVITY OF FERTIRRIGATED AÇAÍ
ABSTRACT This study aimed to define management zones (MZs) for fertirrigated açaí cultivation, based on spatial variability of the foliar nutrients and productivity data. The work was carried out in an area of 5.75 ha of a 7-year crop, with 80 georeferenced sample points. Fresh fruit productivity and nutrient (N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn) con
Eng. Agríc.. Publicado em: 2020-12