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1.
Plants (Basel) ; 13(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38732419

RESUMO

In the framework of precision viticulture, satellite data have been demonstrated to significantly support many tasks. Specifically, they enable the rapid, large-scale estimation of some viticultural parameters like vine stem water potential (Ψstem) and intercepted solar radiation (ISR) that traditionally require time-consuming ground surveys. The practice of covering table grape vineyards with plastic films introduces an additional challenge for estimation, potentially affecting vine spectral responses and, consequently, the accuracy of estimations from satellites. This study aimed to address these challenges with a special focus on the exploitation of Sentinel-2 Level 2A and meteorological data to monitor a plastic-covered vineyard in Southern Italy. Estimates of Ψstem and ISR were obtained using different algorithms, namely, Ordinary Least Square (OLS), Multivariate Linear Regression (MLR), and machine learning (ML) techniques, which rely on Random Forest Regression, Support Vector Regression, and Partial Least Squares. The results proved that, despite the potential spectral interference from the plastic coverings, ISR and Ψstem can be locally estimated with a satisfying accuracy. In particular, (i) the OLS regression-based approach showed a good performance in providing accurate ISR estimates using the near-infrared spectral bands (RMSE < 8%), and (ii) the MLR and ML algorithms could estimate both the ISR and vine water status with a higher accuracy (RMSE < 7 for ISR and RMSE < 0.14 MPa for Ψstem). These results encourage the adoption of medium-high resolution multispectral satellite imagery for deriving satisfying estimates of key crop parameters even in anomalous situations like the ones where plastic films cover the monitored vineyard, thus marking a significant advancement in precision viticulture.

2.
Front Plant Sci ; 12: 692661, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34434204

RESUMO

The domestication and spreading of grapevine as well as the gene flow history had been described in many studies. We used a high-quality 7k SNP dataset of 1,038 Eurasian grape varieties with unique profiles to assess the population genetic diversity, structure, and relatedness, and to infer the most likely migration events. Comparisons of putative scenarios of gene flow throughout Europe from Caucasus helped to fit the more reliable migration routes around the Mediterranean Basin. Approximate Bayesian computation (ABC) approach made possible to provide a response to several questions so far remaining unsolved. Firstly, the assessment of genetic diversity and population structure within a well-covered dataset of ancient Italian varieties suggested the different histories between the Northern and Southern Italian grapevines. Moreover, Italian genotypes were shown to be distinguishable from all the other Eurasian populations for the first time. The entire Eurasian panel confirmed the east-to-west gene flow, highlighting the Greek role as a "bridge" between the Western and Eastern Eurasia. Portuguese germplasm showed a greater proximity to French varieties than the Spanish ones, thus being the main route for gene flow from Iberian Peninsula to Central Europe. Our findings reconciled genetic and archaeological data for one of the most cultivated and fascinating crops in the world.

3.
Front Plant Sci ; 11: 605934, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33584749

RESUMO

The Italian grape germplasm is characterized by a high level of richness in terms of varieties number, with nearly 600 wine grape varieties listed in the Italian National Register of Grapevine Varieties and with a plethora of autochthonous grapes. In the present study an extended SNP genotyping has been carried out on Italian germplasm of cultivated Vitis vinifera subsp. sativa and Vitis hybrids. Several hundred Italian varieties maintained in the repositories of scientific Institutions and about one thousand additional varieties derived from previous studies on European, Southern Italy, Magna Graecia and Georgian germplasm were considered. The large genotyping data obtained were used to check the presence of homonyms and synonyms, determine parental relationships, and identify the main ancestors of traditional Italian cultivars and closely-related accessions. The parentage among a set of 1,232 unique varieties has been assessed. A total of 92 new parent-offspring (PO) pairs and 14 new PO trios were identified. The resulted parentage network suggested that the traditional Italian grapevine germplasm originates largely from a few central varieties geographically distributed into several areas of genetic influence: "Strinto porcino" and its offspring "Sangiovese", "Mantonico bianco" and "Aglianico" mainly as founder varieties of South-Western Italy (IT-SW); Italian Adriatic Coast (IT-AC); and Central Italy with most varieties being offsprings of "Visparola", "Garganega" and "Bombino bianco"; "Termarina (Sciaccarello)" "Orsolina" and "Uva Tosca" as the main varieties of North-Western Italy (IT-NW) and Central Italy. The pedigree reconstruction by full-sib and second-degree relationships highlighted the key role of some cultivars, and, in particular, the centrality of "Visparola" in the origin of Italian germplasm appeared clear. An hypothetical migration of this variety within the Italian Peninsula from South to North along the eastern side, as well as of "Sangiovese" from South to Central Italy along the Western side might be supposed. Moreover, it was also highlighted that, among the main founders of muscat varieties, "Moscato bianco" and "Zibibbo (Muscat of Alexandria)" have spread over the whole Italy, with a high contribution by the former to germplasm of the North-Western of the peninsula.

4.
Sci Total Environ ; 645: 1221-1229, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30248847

RESUMO

Polymeric protein-based biocomposites were used in this work as water dispersions to generate, in situ, biobased mulching coatings by spray technique, as alternative to low density polyethylene films for soil mulching. At the end of their lifetime, these biodegradable coatings degrade in soil thank to the microbial community that mineralizes them. Protein hydrolysates (PH) were derived from waste products of the leather industry, while poly(ethylene glycol) diglycidyl ether (PEG) and epoxidized soybean oil (ESO) were used to make the biodegradable spray coatings. A study under greenhouse condition was carried out using seedling test plots in order to investigate the performance of the spray coatings and their possible influence on some aspects of leaf growth, functionality and nutritional quality of lettuce (Lactuca sativa L., Mortarella selection Romanella variety Duende) and on soil properties. The biodegradable coatings showed the same good agronomic performances comparable with the ones of a commercial low density polyethylene mulching film, maintaining the mulching effect for the requested cultivation period and ensuring at the same time a similar rate of plant growth and dry matter accumulation. The research showed that 2 months after the tillage carried out at the end of the cultivation the amount of coating residues present in the soil was <5% of the initial weight of the biodegradable coatings. At the end of the field test, the soil mulched with the polyethylene film recorded an electrical conductivity value lower with respect to the soil mulched with the sprayed coatings, which release nutrients in the soil during their decomposition.


Assuntos
Agricultura/métodos , Solo/química , Folhas de Planta , Água
5.
Food Res Int ; 75: 260-269, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28454955

RESUMO

Field studies were conducted in Puglia (Italy) to evaluate the influence of defoliation around cluster zones on grape and wine quality. Nero di Troia grapes were subjected to four different treatments: N: no leaf removal; E: leaf removal in the area of the clusters along the east side (at complete veraison); E/W: leaf removal in the area of the clusters along the east and west side (at complete veraison); and F: almost complete leaf removal along the west side (at complete veraison) and at pre-harvest also along the east side. Grapes of defoliated vines generally showed higher sugar content, lower titratable acidity, total flavonoids, flavonoids different from anthocyanins, and total phenolic content than grapes from non-defoliated vines while their total anthocyanin concentration was not affected by defoliation at a significant level. Concerning wines, alcohol content, residual soluble solids, different forms of anthocyanins but also volatile acidity were generally higher in samples from defoliated vines. Differences were also highlighted among the defoliation treatments: the best results in terms of dry matter, sugar and alcohol content were observed in the samples submitted to the more severe defoliation as a consequence of the higher light availability and berry temperature. Concerning the concentration of the individual phenolics, significant differences were highlighted for: caffeic and caftaric acids, peonidin- and malvidin-3-p-coumaroylglucoside, which were higher in the E wines; quercetin-3-glucoside, galactoside, and rhamnoside, and procyanidins, which were higher in F wines.

6.
Respirology ; 11(5): 627-32, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16916337

RESUMO

OBJECTIVE AND BACKGROUND: The Fifteen-Count Breathlessness Score (15CBS) has been reported to quantify breathlessness. The aim of this study was to determine the reliability and validity of the 15CBS in adults with COPD. METHODS: Using an observational correlation design, subjects with clinical signs and symptoms of COPD were videotaped performing the 15CBS at a self-selected (task 1) and an 8-s counting pace (task 2), on two occasions with 5-min rest between attempts. Respiratory-related quality of life questionnaires, self-report shortness of breath measures and pulmonary function tests were completed by all subjects. RESULTS: Thirty subjects completed the protocol. No significant differences and good linear relationships were calculated for the 15CBS within subjects (task 1 P = 0.32, r = 0.75 and task 2 P = 1.00, r = 0.86) and between assessors (task 1 P = 0.57, r = 0.99 and task 2 P = 0.21, r = 0.75). No significant relationships were evident between the 15CBS and shortness of breath or quality of life scores. Significant relationships existed between the 15CBS and FVC (litres and per cent predicted). CONCLUSION: Most subjects completed the 15CBS using one breath, limiting discrimination between subjects with differing degrees of breathlessness. Although data from this study confirmed that the 15CBS is a reliable procedure within people with COPD, further modification is required to increase the validity and discriminative ability of this instrument.


Assuntos
Doença Pulmonar Obstrutiva Crônica/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Testes de Função Respiratória/métodos
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