Search results for "Lactuca"
showing 10 items of 25 documents
Effetto della forma azotata e della modalità di distribuzione sulla produzione e la qualità di lattuga
2009
A chematoxonomic review of the subtribe crepidinase based on its phenol constituents
1994
Abstract The chemotaxonomical significance of flavonoids, phenolic acids and coumarins from 20 species, belonging to eight genera of the subtribe Crepidinae (family Compositae), is discussed. The content in phenolic compounds of three species of Lactuca (L. tenerrima, L. virosa and L. muralis ) is reported for the first time.
Similar Effects of Ozone on Four Cultivars of Lettuce in Open Top Chambers During Winter
2002
Ozone is the major phytotoxic air pollutant that reduces the yield of several agricultural crops in the Spanish Mediterranean area. We studied four lettuce cultivars (Lactuca sativa L.) for the effects of different O3 concentrations during the winter on chlorophyll (Chl) a fluorescence, lipid peroxidation, and root length in outdoor open-top chambers. Under O3 the photosynthetic quantum conversion declined while heat emissions increased in all cultivars; these results provide more evidence of non-filtered air with additional ozone (NFA+O3) treatment compared with non-filtered air (NFA) and charcoal filtered ozone-free air (CFA). Changes in the Chl a fluorescence may be associated with an in…
Prediction of potential environmental toxicity of chemicals in <em>Lactuca sativa</em> seed germination using computational tools
2019
The main aim of the study was to develop quantitative structure-activity relationship (QSAR) models for the prediction of phytotoxicity effects of chemical compounds on the Lactuca sativa seeds germination. A database of 73 compounds, assayed against L. sativa and Dragon’s molecular descriptors are used to obtain a QSAR model for the prediction of the phytotoxicity. The model is carried out with QSARINS software and validated according to OECD principles. The best model showed good value for the determination coefficient (R2 = 0.917) and others parameters appropriate for fitting (s = 0.256 and RMSEtr= 0.236). The validation results confirmed that the model has good robustness and stability …
Experimental rearing of the sea urchinParacentrotus lividusfed with discards of the lettuceLactuca sativain a sea-based system
2017
Small-sized specimens (test diameter: 16.64 ± 0.93 mm, mean ± SE) of the sea urchin Paracentrotus lividus were fed with fresh discards of the lettuce Lactuca sativa during a 24-week experiment in a sea-based system. At the end of the experiment, stock survival was high (88.8 ± 6.6%). Sea urchin test diameter and total weight grew by 35% and 56%, respectively, while gonad somatic index, after an initial decrease, increased by 3.2%. Moreover, more than 90% of specimens achieved the gonad colour that the market demands. These results support the exploitation of L. sativa as the main ingredient in a manufactured diet for echinoculture of P. lividus. Employing diets formulated with discard ingre…
Use of fresh vegetable discards as sea urchin diet: effect on gonad index and quality
2014
This study evaluated the exploitation of unprocessed agricultural discards in the form of fresh vegetable leaves as a diet for the sea urchin Paracentrotus lividus through the assessment of their effects on gonad yield and quality. A stock of wild-caught P. lividus was fed on discarded leaves from three different species (Beta vulgaris, Brassica oleracea, and Lactuca sativa) and the macroalga Ulva lactuca for 3 months under controlled conditions. At the beginning and end of the experiment, total and gonad weight were measured, while gonad and diet total carbon (C%), nitrogen (N%), δ13C, δ15N, carbohydrates, lipids, and proteins were analyzed. The results showed that agricultural discards pr…
Influence of Ecklonia maxima Extracts on Growth, Yield, and Postharvest Quality of Hydroponic Leaf Lettuce
2021
Ecklonia maxima is a brown algae seaweed largely harvested over the last years and used to produce alginate, animal feed, fertilizers, and plant biostimulants. Their extracts are commercially available in various forms and have been applied to many crops for their growth-promoting effects which may vary according to the treated species and doses applied. The aim of the study was to characterize the effect of adding an Ecklonia maxima commercial extract (Basfoliar Kelp
Evaluación de la toxicidad y de la bioacumulación del Cu en un cultivo acumulador (Lactuca sativa L.) y otro no-acumulador (Solanum lycopersicum L.) …
2015
Las principales conclusiones de la presente Tesis son: 1. Los valores de toxicidad establecidos para los diferentes suelos cultivados con lechuga de las diferentes regiones agrícolas mediterráneas consideradas abarcaron rangos similares, siendo de 8 a 752 mgCu/kg en la región española y de 49 a 728 mgCu/kg en la australiana. En ambos casos, el valor máximo se obtuvo para el suelo con el mayor pH y el mayor contenido en arcilla, independientemente del tipo de suelo. Por tanto, estas dos propiedades edáficas son muy relevantes a la hora de analizar y evaluar la movilidad y la disponibilidad del Cu en el suelo. La diferencia entre los valores máximos obtenidos para cada área se puede deber al …
SALINITY EFFECTS ON ENZYMATIC BROWNING AND ANTIOXIDANT CAPACITY OF FRESH-CUT BABY ROMAINE LETTUCE (LACTUCA SATIVA L. CV. DUENDE)
2010
Abstract Enzymatic browning is a main problem encountered in minimal processing and further storage of leafy vegetables, leading to shorter shelf-life of products. Changes in the two oxidative activities, polyphenol oxidase (PPO) and peroxidase (POD), as well as in total phenolic content, colour parameters and antioxidant capacity (assayed with ORAC method), were monitored during 10 days of storage at 4 °C of minimally processed baby Romaine lettuce ( Lactuca sativa L. cv. Duende) cultivated under three different salinity conditions (2.8, 3.8 and 4.8 dS m −1 ), in order to determine the most suitable condition for further processing. Increasing levels of salinity reduced both oxidases activ…
Composition and allelopathic effect of essential oils of two thistles: Cirsium creticum (Lam.) D.�Urv. ssp. triumfetti (Lacaita) Werner and Carduus n…
2007
Abstract Cirsium and Carduus are two of the main genera of true thistles. Different species in these genera share a quantity of secondary metabolites and have interesting ecological properties. The essential oils of two species, Cirsium creticum and Carduus nutans, were analysed, showing the presence as main compounds of 4-ethyl guaiacol (15%), hexadecanoic acid (10.6%), (E)-β-damascenone (7.8%), dihydroactinidiolide (6.0%) and 4-vinyl guaiacol (4.5%) for C. creticum and hexadecanoic acid (18.6%), hexahydrofarnesylacetone (7.8%), heptacosane (5.9%), 4-vinyl guaiacol (5.8%), pentacosane (3.8%) and eugenol (3.6%) for C. nutans. The oils were evaluated at different doses for their effect on ge…