Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Chemosphere ; 238: 124651, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31472346

RESUMO

A harbour sediment, previously remediated, was tested for soilless strawberry cultivation (Camarosa and Monterey cultivars), as an innovative, cost-effective and environment-friendly approach of sediment management. Sediments were tested as such (TS100) and mixed 1/1 (v/v) with a peat-based commercial substrate (TS50), using the peat-based medium as control (TS0). Substrates were characterized for some physicochemical properties (e.g. density, porosity and water capacity). Minerals (P, Ca, K, Na and Fe), heavy metals (Cu, Zn, Mn, Ni, Cr, Pb and Cd), aliphatic hydrocarbons (C > 12), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dibenzodioxins and dibenzofurans were analysed in substrates and fruits. Sugars and organic acids, including the ascorbic, were also determined in fruits, as quality indicators. Notwithstanding remediation, sediments showed concentrations of Zn (206 mg kg-1), C > 12 (86 mg kg-1) and PAHs (47 mg kg-1) exceeding the limits established by the Italian L.D. 152/2006, regulating the contamination of soil in green areas, thus making its relocation in the environment not permitted as such. No evidence of fruit contamination by Cr, Pb and Cd was highlighted. Moreover, Cu, Zn and Ni fruit concentrations were comparable among treatments. Conversely, Mn showed statistically higher concentrations in TS0 fruits (56-57 mg kg-1) compared to those grown in sediment-based substrates (8-20 mg kg-1). Among organic contaminants, only dioxin-like PCBs were determined in fruits, at toxic equivalent concentrations fourfold lower than the limit established by the European Union. TS100 fruits showed a yield reduction from 40 to 70% for Camarosa and Monterey, but higher sugar and ascorbic acid contents.


Assuntos
Produtos Agrícolas/normas , Monitoramento Ambiental , Fragaria/metabolismo , Frutas/química , Sedimentos Geológicos/química , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Fragaria/química , Itália , Metais Pesados/análise , Minerais/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/química
2.
Ecotoxicol Environ Saf ; 180: 588-599, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31132554

RESUMO

Past studies have already determined that selenium (Se) is very effective in alleviating cell oxidative damage caused by various abiotic stresses in plants. Past studies have also indicated other physiological pathways by which Se may benefit plants. In order to better understand the full array of potential applications for Se in agriculture, this study investigated the influence of Se on carbohydrate and nitrogen (N) metabolism in potato plants (Solanum tuberosum L. cv. Sante) grown under cadmium (Cd) and/or arsenic (As) toxicity. Potato plants were grown in a growth chamber and fertigated with Hoagland nutrient solution with or without Se (9 µM). After 48-d of growth under Cd (40 µM) and/or As (40 µM) stress, carbohydrate and N metabolism in leaves, roots and stolons were measured. For carbohydrate metabolism, various sugars-i.e., sucrose, starch, glucose, fructose, and total soluble sugar contents (TSSC)-and the activities of enzymes associated with sucrose metabolism and glycolysis-i.e., acid invertase (AI), neutral invertase (NI), sucrose-synthetase (SS), sucrose phosphatesynthetase (SPS), fructokinase (FK), hexokinase (HK), phosphofructokinase (PFK), and pyruvatekinase (PK)-were measured. For N metabolism, NO3-, NO2- and NH4+ contents along with the enzymatic activities of nitrate reductase (NRA), nitrite reductase (NiRA), glutamine-synthetase (GS), and glutamate-synthetase (GOGAT) were measured. Overall, Cd and/or As treatments had reduced plant growth relative to those plants grown without heavy metal toxicity, due to hindered photosynthesis and alterations in N metabolism and glycolysis. Regarding N metabolism, heavy metal toxicity caused a reduction in NO3- and NO2- content and NRA and NiRA enzymatic activity and enhanced NH4+ content and GDH activity in leaves, roots and stolons. Regarding glycolysis, the activity of enzymes of glycolysis-i.e., FK, HK, PFK, and PK-were also reduced. In the C metabolism study, plants combatted Cd and As toxicity naturally by an adaptation mechanism which caused an increase in soluble sugars (fructose, glucose, sucrose) by increasing NI, SS and SSP enzymatic activity. Supplementation with Se in the Cd and/or As treatments in the carbohydrate and N metabolism studies improved plant growth. Selenium supplementation in the Cd and As treatments decreased Cd and/or As content in the plant tissue and alleviating the Cd- and/or As-induced toxicity by enhancing the C-metabolism adaptation mechanism. Applying Se to Cd and As treatments also decreased nitrogen losses by hindering Cd- and As-induced changes in the N-metabolism. Se also limited Cd and As accumulation in the plant tissue by the antagonistic effect between Cd/Se and As/Se in the roots. The results of this study indicate that in the presence of Cd and/or As. soil toxicity, Se may be a powerful tool for promoting plant growth.


Assuntos
Arsênico/toxicidade , Cádmio/toxicidade , Metabolismo dos Carboidratos/efeitos dos fármacos , Nitrogênio/metabolismo , Selênio/farmacologia , Solanum tuberosum/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Solanum tuberosum/metabolismo , Estresse Fisiológico , Sacarose/metabolismo
3.
Ecotoxicol Environ Saf ; 173: 322-330, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30784795

RESUMO

This study explores the possibility of using mycorrhization as a novel technique for diminishing the negative effects of boron (B) in the nutrient solution on seedlings of Carrizo citrange rootstock plants. For this, an experiment was planned for studying the physiological (gas exchange and chlorophyll fluorescence parameters), morphological (vegetative growth parameters), nutritional (organic solutes, carbohydrates) and oxidative stress responses of seedlings that were either mycorrhized (+AM, Rhizophagus irregularis; previously known as Glomus intraradices) or not mycorrhized (-AM), and irrigated with water containing different concentrations of B (0.5, 5 and 10 mg L-1). It was observed that an excess of B in the nutrient solution decreased the vegetative growth in both +AM and -AM plants, but this decrease was greater in -AM plants. Mycorrhized plants (+AM) under high B concentration accumulated less B in the leaves, and had a smaller reduction of net assimilation rate of CO2 and lower MDA concentration than non-mycorrhized plants. Thus, it can be concluded that mycorrhization increased the tolerance to high boron concentration in the irrigation water of citrange Carrizo seedlings by reducing both the B concentration in the plant tissue and the B toxicity in the physiological processes. The study of organic solutes and carbohydrates also pointed to a different response model between +AM and -AM plants that could be related to the different tolerance observed between these plants.


Assuntos
Boro/metabolismo , Citrus/metabolismo , Citrus/microbiologia , Glomeromycota/fisiologia , Micorrizas/fisiologia , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Simbiose
4.
J Sci Food Agric ; 94(1): 85-94, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23633390

RESUMO

BACKGROUND: Very-early apricot cultivars are interesting owing to the fact that they will be available in markets before any other cultivar. In order to achieve good fruit quality, very-early apricots require appropriate size, weight and color, good balance of sugars and organic acids, proper content of bioactive compounds, relatively strong apricot aroma as well as acceptable sensory quality. RESULTS: Physical, chemical, antioxidant and sensory properties showed important variations among apricot cultivars. These differences were basically attributed to genetic reasons. Four very-early apricot cultivars were studied, namely 'Mirlo Blanco', 'Mirlo Anaranjado', 'Colorao' and 'Mogador'. All of them showed proper size and weight, but their contents of organic acids, sugars and bioactive compounds were low and the number of volatile compounds was also low. However, very-early apricots showed an appropriate sensory profile for fresh consumption. CONCLUSION: Regarding physical, chemical and volatile composition and sensory properties, very-early apricot cultivars could be recommended for fresh consumption. However, future research must be focused on increasing their contents of sugars, organic acids and bioactive and volatile compounds, perhaps via cultural practices such as deficit irrigation and/or mulching.


Assuntos
Antioxidantes/análise , Frutas/química , Prunus , Sensação , Compostos Orgânicos Voláteis/análise , Adulto , Agricultura/métodos , Carboidratos/análise , Ácidos Carboxílicos/análise , Cor , Feminino , Frutas/anatomia & histologia , Frutas/crescimento & desenvolvimento , Humanos , Masculino , Pessoa de Meia-Idade , Odorantes/análise , Polifenóis/análise , Olfato , Especificidade da Espécie
5.
Plant Foods Hum Nutr ; 68(4): 370-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23979495

RESUMO

The objective of this study was to evaluate and compare, for the first time, white and black mulberry species in terms of main phytochemical, volatile composition and sensory profile characteristics in eight Spanish clones. The results showed that black and white mulberry species displayed significant different characteristics. PLS analysis has allowed grouping of the clones into four groups (i) MA1, MA2 and MN2, (ii) MN3 and MN4, (iii) MA3 and MA4, and (iv) MN1. Experimental results proved that Spanish mulberries have potential for fresh consumption due to their high antioxidant capacity (10.7-86.1 mg Trolox 100 g(-1)), polyphenol (76.7-180 mg gallic acid 100 g(-1)) and ellagic acid content (8.7-15.5 mg 100 g(-1)) as well as considerable amount of volatile compounds (35) with desirable attributes, which were scored high by a trained panel. Cultivars from the Morus nigra species seem to provide fruits with higher content of bioactive compounds and better aptitude for fresh consumption than Morus alba. Differences among the species should be attributed to genetics because they were cultivated under same conditions.


Assuntos
Antioxidantes/análise , Ácido Elágico/análise , Qualidade dos Alimentos , Frutas/química , Morus/química , Óleos Voláteis/análise , Polifenóis/análise , Dieta , Humanos , Espanha , Especificidade da Espécie , Paladar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA