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1.
Sensors (Basel) ; 23(24)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38139530

RESUMEN

The development of spectral sensors (SSs) capable of retrieving spectral information have opened new opportunities to improve several environmental and agricultural practices, e.g., crop breeding, plant phenotyping, land use monitoring, and crop classification. The SSs are classified as multispectral and hyperspectral (HS) based on the number of the spectral bands resolved and sampled during data acquisition. Large-scale applications of the HS remain limited due to the cost of this type of technology and the technical difficulties in hyperspectral data processing. Low-cost portable hyperspectral cameras (PHCs) have been progressively developed; however, critical aspects associated with data acquisition and processing, such as the presence of spectral discontinuities, signal jumps, and a high level of background noise, were reported. The aim of this work was to analyze and improve the hyperspectral output of a PHC Senop HSC-2 device by developing a general use methodology. Several signal gaps were identified as falls and jumps across the spectral signatures near 513, 650, and 930 nm, while the dark current signal magnitude and variability associated with instrumental noise showed an increasing trend over time. A data correction pipeline was successfully developed and tested, leading to 99% and 74% reductions in radiance signal jumps identified at 650 and 830 nm, respectively, while the impact of noise on the acquired signal was assessed to be in the range of 10% to 15%. The developed methodology can be effectively applied to other low-cost hyperspectral cameras.

2.
Plants (Basel) ; 12(8)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37111953

RESUMEN

Recent developments in low-cost imaging hyperspectral cameras have opened up new possibilities for high-throughput phenotyping (HTP), allowing for high-resolution spectral data to be obtained in the visible and near-infrared spectral range. This study presents, for the first time, the integration of a low-cost hyperspectral camera Senop HSC-2 into an HTP platform to evaluate the drought stress resistance and physiological response of four tomato genotypes (770P, 990P, Red Setter and Torremaggiore) during two cycles of well-watered and deficit irrigation. Over 120 gigabytes of hyperspectral data were collected, and an innovative segmentation method able to reduce the hyperspectral dataset by 85.5% was developed and applied. A hyperspectral index (H-index) based on the red-edge slope was selected, and its ability to discriminate stress conditions was compared with three optical indices (OIs) obtained by the HTP platform. The analysis of variance (ANOVA) applied to the OIs and H-index revealed the better capacity of the H-index to describe the dynamic of drought stress trend compared to OIs, especially in the first stress and recovery phases. Selected OIs were instead capable of describing structural changes during plant growth. Finally, the OIs and H-index results have revealed a higher susceptibility to drought stress in 770P and 990P than Red Setter and Torremaggiore genotypes.

3.
Ann Bot ; 124(4): 567-580, 2019 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-30566593

RESUMEN

BACKGROUND AND AIMS: The development of Arundo donax as a biomass crop for use on drought-prone marginal lands in areas with warm to hot climates is constrained by the lack of variation within this species. We investigated the effect of morphological and physiological variation on growth and tolerance to drought under field conditions in three ecotypes of A. donax collected from habitats representing a climate gradient: a pre-desert in Morocco, a semi-arid Mediterranean climate in southern Italy and a warm sub-humid region of central Italy. METHODS: The three A. donax ecotypes were grown under irrigated and rain-fed conditions in a common garden field trial in a region with a semi-arid Mediterranean climate. Physiological and morphological characteristics, and carbohydrate metabolism of the ecotypes were recorded to establish which traits were associated with yield and/or drought tolerance. KEY RESULTS: Variation was observed between the A. donax ecotypes. The ecotype from the most arid habitat produced the highest biomass yield. Stem height and the retention of photosynthetic capacity later in the year were key traits associated with differences in biomass yield. The downregulation of photosynthetic capacity was not associated with changes in foliar concentrations of sugars or starch. Rain-fed plants maintained photosynthesis and growth later in the year compared with irrigated plants that began to senescence earlier, thus minimizing the difference in yield. Effective stomatal control prevented excessive water loss, and the emission of isoprene stabilized photosynthetic membranes under drought and heat stress in A. donax plants grown under rain-fed conditions without supplementary irrigation. CONCLUSIONS: Arundo donax is well adapted to cultivation in drought-prone areas with warm to hot climates. None of the A. donax ecotypes exhibited all of the desired traits consistent with an 'ideotype'. Breeding or genetic (identification of quantitative trait loci) improvement of A. donax should select ecotypes on the basis of stem morphology and the retention of photosynthetic capacity.


Asunto(s)
Sequías , Fotosíntesis , Italia , Poaceae , Estaciones del Año
4.
Front Plant Sci ; 8: 1016, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28659959

RESUMEN

The function of dimethylsulphoniopropionate (DMSP) in plants is unclear. It has been proposed as an antioxidant, osmolyte and overflow for excess energy under stress conditions. The formation of DMSP is part of the methionine (MET) pathway that is involved in plant stress responses. We used a new analytical approach to accurately quantify the changes in DMSP concentration that occurred in two ecotypes of the biomass crop Arundo donax subject to moderate drought stress under field conditions. The ecotypes of A. donax were from a hot semi-arid habitat in Morocco and a warm-humid environment in Central Italy. The Moroccan ecotype showed more pronounced reductions in photosynthesis, stomatal conductance and photochemical electron transport than the Italian ecotype. An increase in isoprene emission occurred in both ecotypes alongside enhanced foliar concentrations of DMSP, indicative of a protective function of these two metabolites in the amelioration of the deleterious effects of excess energy and oxidative stress. This is consistent with the modification of carbon within the methyl-erythritol and MET pathways responsible for increased synthesis of isoprene and DMSP under moderate drought. The results of this study indicate that DMSP is an important adaptive component of the stress response regulated via the MET pathway in A. donax. DMSP is likely a multifunctional molecule playing a number of roles in the response of A. donax to reduced water availability.

5.
Aging Clin Exp Res ; 28(3): 459-68, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26873817

RESUMEN

UNLABELLED: The patients' adherence to osteoporosis treatments is low. In our study population a history of osteoporotic fractures was associated to better compliance and persistence; however, a 12-month randomized study carried out on 816 osteoporotic women showed that providing the patients with their individual fracture risk information did not prove effective. PURPOSE: Several drugs are currently available for the treatment of osteoporosis, but the patients' compliance and persistence with these treatments are low. This study aimed to both analyze the adherence to oral osteoporosis medications among Italian osteoporotic patients (cross-sectional study) and evaluate if providing patients with their individual fracture risk information may improve compliance and persistence (prospective study). METHODS: A total of 3379 osteoporotic patients referred as outpatients for a visit 1 year after receiving a prescription of oral osteoporosis medications for the first time, were enrolled for the retrospective study. Moreover, 816 postmenopausal women receiving an oral prescription for osteoporosis for the first time, were randomized into two groups: group 1 (managed according to standard clinical practice) and group 2 (managed with greater patient involvement and information on the individual risk of major osteoporotic fractures calculated by DeFRA algorithm). RESULTS: In the retrospective study, a history of osteoporotic fractures, the frequency of drug administration and a condition of being overweight/obese had a significant influence on both compliance and persistence. Of the 816 patients enrolled in the longitudinal study, 731 (374 of group 1 and 357 of group 2) attended the 1 year follow-up visit. The percentage of women with high compliance or persistence was greater in group 2 (64.2 vs. 58.1 % and 66.8 vs. 62.6 %, respectively), but without reaching any statistical significance. CONCLUSIONS: Although providing the patients with their individual fracture risk information was not statistically effective, further studies on additional interventions able to improve the patients' perceived risk of fracture are warranted.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Cumplimiento de la Medicación , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas Osteoporóticas/prevención & control , Administración Oral , Anciano , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Fracturas Osteoporóticas/etiología , Estudios Prospectivos , Estudios Retrospectivos , Riesgo
6.
J Agric Food Chem ; 62(11): 2436-42, 2014 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-24559213

RESUMEN

Ten accessions of grass pea (Lathyrus sativus L.) from different Sicilian sites, cultivated in the same environmental conditions, were analyzed for their morphological and productive parameters and for the content of two non-protein amino acids: α- and ß-ODAP (α- and ß-N-oxalyl-l-α,ß-diaminopropionic acid). The ß-isomer is the neurotoxin responsible for the neuron disease known as lathyrism. This analysis was carried out using two common analytical methodologies never applied in their determination, an HPLC separation with evaporative light scattering (ELS) as detector, and nuclear magnetic resonance (NMR). The content of the two isomers falls in the range reported for these compounds: 0.42-0.74 and 2.69-4.59 g/kg for α- and ß-ODAP, respectively; and the two methods yield comparable results. High productivity and a high protein content were detected in three Sicilian accessions. Low ß-ODAP content was found to be linked to accessions with heavier seeds and those originating at lower altitudes.


Asunto(s)
Lathyrus/química , Extractos Vegetales/química , beta-Alanina/análogos & derivados , Cromatografía Líquida de Alta Presión , Isomerismo , Espectroscopía de Resonancia Magnética , Extractos Vegetales/aislamiento & purificación , Sicilia , beta-Alanina/química , beta-Alanina/aislamiento & purificación
7.
Food Chem ; 140(4): 810-6, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23692770

RESUMEN

"Cipolla di Giarratana", a locally cultivated white onion landrace, is listed as an item in the 'List of Traditional Agro-food Products' of the Italian Department for Agriculture and itemised as 'slow food presidium' by the Slow Food Foundation. Ten local accessions were investigated for their biomorphological and biochemical characteristics in five experimental locations. High-performance liquid chromatography coupled with diode array detection and electron spray-mass spectrometry (HPLC/DAD/ESI-MS) was used to identify the phenolic profile and quantify phenolic content in bulbs: quercetin, quercetin 3,4' di-O-glucoside and quercetin 4'-O-glucoside were detected as major components. The 'Cipolla di Giarratana' landrace is characterised by a high bulb weight (436g) and high diameter (11cm). The total flavonols content ranged between 68 and 408mgkg(-1) bulb fresh weight in nine of the 10 collected accessions. The opportunity of considering flavonol patterns as chemotaxonomic descriptors in order to characterise onion germplasm is also discussed.


Asunto(s)
Flavonoles/análisis , Cebollas/química , Identificación Biométrica/métodos , Cromatografía Líquida de Alta Presión , Cebollas/clasificación , Cebollas/genética , Fenoles/análisis , Sicilia , Espectrometría de Masa por Ionización de Electrospray
8.
J Sci Food Agric ; 93(14): 3512-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23633295

RESUMEN

BACKGROUND: The heightened consumer awareness for food safety is reflected in the demand for products with well-defined individual characteristics due to specific production methods, composition and origin. In this context, of pivotal importance is the re-evaluation of folk/traditional foods by properly characterizing them in terms of peculiarity and nutritional value. The subjects of this study are two typical Mediterranean edible products. The main morphological, biometrical and productive traits and polyphenol contents of three onion genotypes ('Cipolla di Giarratana', 'Iblea' and 'Tonda Musona') and three long-storage tomato landraces ('Montallegro', 'Filicudi' and 'Principe Borghese') were investigated. RESULTS: Sicilian onion landraces were characterized by large bulbs, with 'Cipolla di Giarratana' showing the highest bulb weight (605 g), yield (151 t ha(-1)) and total polyphenol content (123.5 mg kg(-1)). Landraces of long-storage tomato were characterized by low productivity (up to 20 t ha(-1)), but more than 70% of the total production was obtained with the first harvest, allowing harvest costs to be reduced. High contents of polyphenols were found, probably related to the typical small fruit size and thick skin characterizing these landraces. CONCLUSION: The present study overviews some of the most important traits that could support traditional landrace characterization and their nutritional value assessment.


Asunto(s)
Cebollas/química , Polifenoles/análisis , Solanum lycopersicum/química , Fenómenos Químicos , Cultura , Dieta Mediterránea , Alimentos , Genotipo , Solanum lycopersicum/genética , Valor Nutritivo , Cebollas/genética , Raíces de Plantas/anatomía & histología , Raíces de Plantas/química , Sicilia , Especificidad de la Especie
9.
J Agric Food Chem ; 60(1): 309-14, 2012 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-22117757

RESUMEN

"Long-storage" tomato ( Solanum lycopersicum L.) is a niche product typical of the Mediterranean area, traditionally cultivated under no water supply, the fruits of which combine a good taste with excellent nutritional properties. High-performance liquid chromatography coupled with diode array detection and electron spray-mass spectrometry (HPLC/DAD/ESI-MS) was used to identify the phenolic profile in 10 landraces of long-storage tomato, grown under a typical semiarid climate, as compared to a processing tomato hybrid cultivated in the same environment, under both well-irrigated and unirrigated conditions. Sixteen different secondary metabolites, belonging to the classes of cinnamoylquinic acids and flavonoids, were identified. Quantitative analyses were also performed to monitor the changes in the phenolic content along the batch. The results highlighted that landraces originating from the same area exhibit different fruit morphologies but own a similar biochemical profile. Moreover, the two controls (well irrigated and unirrigated) are placed into the same cluster, suggesting that these secondary metabolites in tomato fruits may be more genetics-dependent than environment-dependent. Given the analysis of phenols nowadays represents a useful tool to assess the genetic variability in tomato, these compounds could be adopted as chemotaxonomic markers in the traceability of this niche product.


Asunto(s)
Polifenoles/análisis , Solanum lycopersicum/química , Solanum lycopersicum/clasificación , Biomarcadores/análisis , Biomarcadores/metabolismo , Genotipo , Italia , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Polifenoles/metabolismo
10.
Expert Opin Pharmacother ; 12(2): 257-68, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21226636

RESUMEN

INTRODUCTION: Bisphosphonates are the first-choice treatment for osteoporosis. They effectively increase bone mineral density, reduce markers of bone resorption, and lower the incidence of new fractures in patients with osteoporosis-related fracture. However, the efficacy observed in clinical trials may not be realized in a real-life setting, partly due to poor adherence to therapy, with a significant worsening of clinical outcomes. Several issues contribute to poor adherence to osteoporosis medication, including inconvenient dosing regimens and concerns about possible adverse events. Although strategies to improve adherence have been investigated, new approaches are required. AREAS COVERED: We review available data and propose a new approach to improve adherence to osteoporosis therapy in clinical practice. We present the current evidence and personal experience from a group of Italian osteoporosis experts. EXPERT OPINION: To improve adherence, we propose a multifaceted approach, which includes the Triad Model suggested by the World Health Organization, direct observed therapy and the use of drugs with longer administration intervals, e.g., zoledronic acid. The integration of these strategies may provide the basis for a marked increase in adherence to osteoporosis therapy, and improved clinical outcomes in a real-life scenario.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Cumplimiento de la Medicación , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis/tratamiento farmacológico , Algoritmos , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/efectos adversos , Protocolos Clínicos , Costo de Enfermedad , Femenino , Humanos , Osteoporosis/economía , Osteoporosis Posmenopáusica/economía , Resultado del Tratamiento
11.
J Plant Physiol ; 165(8): 796-804, 2008 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-18155805

RESUMEN

Light and temperature-response curves and their resulting coefficients, obtained within ecophysiological characterization of gas exchanges at the leaf level, may represent useful criteria for breeding and cultivar selection and required tools for simulation models aimed at the prediction of potential plant behaviour in response to environmental conditions. Leaf-scale gas exchanges, by means of an IRGA open-flow system, were measured in response to light intensity (8 levels from 0 up to 2000 micromol m(-2) s(-1)), CO(2) concentrations (ambient-350 micromol mol(-1) and short-term enriched-700 micromol mol(-1)) and air temperature (from 7 up to 35 degrees C) on three Vicia faba L. genotypes, each representing one of the three cultivated groups: major, equina and minor. The net assimilation rate response to light intensity was well described by an exponential rise to max function. The short-term CO(2) enrichment markedly increased the values of light response curve parameters such as maximum photosynthetic rate (+80%), light saturation point (+40%) and quantum yield (+30%), while less homogenous behaviour was reported for dark respiration and light compensation point. For each light intensity level, the major and minor genotypes studied showed assimilation rates at least a 30% higher than equina. The positive effects of short-term CO(2) enrichment on photosynthetic water use efficiency (WUE) indicate a relevant advantage in doubling CO(2) concentration. In the major and minor genotypes studied, similar assimilation rates, but different WUE were observed. The optimum leaf temperature for assimilation process, calculated through a polynomial function, was 26-27 degrees C and no relevant limitations were observed in the range between 21 and 32 degrees C. Analysis at the single leaf level provided both rapid information on the variations in gas exchange in response to environmental factors and selection criteria for the screening of genotypes.


Asunto(s)
Dióxido de Carbono/farmacología , Luz , Fotosíntesis/efectos de los fármacos , Fotosíntesis/efectos de la radiación , Temperatura , Vicia faba/metabolismo , Agua/metabolismo , Aire , Genotipo , Fotones , Transpiración de Plantas/efectos de los fármacos , Transpiración de Plantas/efectos de la radiación , Vicia faba/efectos de los fármacos , Vicia faba/genética , Vicia faba/efectos de la radiación
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