1,720,966 research outputs found
EFFECT OF CHRONIC OZONE FUMIGATION ON THE PHOTOSYNTHETIC PROCESS OF POPLAR CLONES SHOWING DIFFERENT SENSITIVITY
No full textGlass Microspheres Covering Film: Agronomic Evaluations on the Production of Cut Flowers
No full textA trial was carried out to evaluate, in the north-centre of Italy, the behaviour
of a new plastic covering film able to scatter light (‘diffract light’), prepared with the
inclusion of empty glass microspheres (“Solex”). The new film was compared to a
covering ‘diffused light’ film (“Agrilux”). Both films had a co-extruded three layers
structure, with the same content of Vinyl acetate. They were tested in two different
conditions (cold tunnel and air conditioned greenhouse), working on two species of
cut flowers, Limonium (Limonium sinuatum Mill.) and three cultivars of carnation
(Dianthus caryophyllus L.). Moreover, the development of some physical and
mechanical characteristics of plastic films were checked. Since the first results, the
innovative film showed a better behaviour than the control one. It presented ‘light’
and ‘thermal’ conditions (lower temperature during the day and slightly higher
temperature in the night, compared to the control film) that allowed a better growth
and yield respect to the control. In fact, Limonium grown under the glass
microspheres film showed higher yield and better commercial quality (stem length).
The analysis of cumulative production in carnation showed different results among
cultivar. For cv ‘Luisa’ and ‘Dandy’, the positive effects of glass microspheres film
were more evident during autumn and winter, while in cv ‘Michelle’, those effects
were higher during warm seasons (October, April, May and June). This could be
explained with the fact that the glass microspheres film provides environmental
conditions that avoid some of the stresses plants undergo during some stages of their cycl
Pacciamatura colorata per il pomodoro: entomofauna ospite e caratteristiche della produzione
No full textCOLOURED MULCHES ON TOMATO CROP (LYCOPERSICON ESCULENTUM MILL.): INSECTS PRESENCE AND YIELD
A comparison trial with a traditional LDPE black film, a yellow film and a brown film, used for mulching an open field tomato crop (Lycopersicon esculentum Mill.), was conducted in order to assess the effect of the films on presence of insects and on yield. Results showed that presence of insects was higher in tomato plants cultivated on coloured films than in the control (plants cultivated without film). In particular a significant prevalence of Thysanoptera was found. The comparison of the number of Thysanoptera specimens captured on mulched treatments revealed no significant differences. In all samplings, the most abundant species was Thrips tabaci, known to be a vector of Tomato Spotted Wilt Virus (TSWV). Presence of other Thysanoptera phytophages and predators was relatively low. In the context examined, the population of T. tabaci did not reach a sufficiently high density to cause crop decay. Moreover, no TSWV symptoms were detected. For these two reasons it can be stated that the species caused no economic damage. As regarding tomato yield, the mulching determined an increment in the fresh and dry weight and in crop production
Impact of Sunlight Spectrum Modification on Yield and Quality of Ready-to-use Lettuce and Rocket Salad Grown on Floating System
No full textThe use of covering plastic materials with specific optical and radiometric
properties, can modify the spectrum of solar radiation and influence some
parameters of vegetables and flowers yield, grown in protected cultivation. For this
reason, the research is oriented to the creation, through different technology, of
plastics able to vary the red/far red ratio (600-700 nm and 700-800 nm of
wavelenght), that regulates the photoreceptors activity in plants. In other cases, the
spectrum modification regards the increase of some wavelenghts through the
transformation of UV radiation. The aim of this research is to check the effect of
solar radiation modified by experimental photoselective films, on growth of ready to
use salad (rocket salad and lettuce) cultivated in a floating system, at different
conditions of solar light (autumn and spring). Yield, dry matter percentage,
antioxidant capacity (FRAP), nitrates, chlorophyll a and b and carotenoid content
were investigated. Results showed that photoselective films (the transmittance
spectrum of the red photoselective film is known, while the one of yellow
photoselective film at the moment can’t be spread because of reasons of licence) had
positive effect on dry matter percentage both for rocket salad and lettuce, while the
fresh weight presented only a slight difference. However photoselective films
increased the nitrates content, parameter easily influenced by a right management
of nutritive solution. Regarding to the antioxidant capacity, measured with FRAP
method, rocket salad showed an increase (around 40%) in plants grown under the
photoselective films. Chlorophyll and carotenoid content was little influenced by the
optical properties of the materials. In conclusion, the use of these innovative
covering films seems to be interesting even for a high value vegetables, especially for the influence on their quality characteristics
Influenza di film plastici a diversa trasmittanza UV sulla qualità di frutti di pomodoro
No full textLa radiazione UV influenza molteplici aspetti del metabolismo vegetale,
inducendo, tra l’altro, la produzione di composti importanti sia per la
protezione della pianta che per il benessere e la salute umana. L’impiego
di film di copertura con buona trasmittanza alla radiazione UV potrebbe
garantire la produzione di ortofrutta arricchita in tali composti. L’influenza
di diversi film di copertura sul contenuto di composti fenolici, flavonoidi
e carotenoidi è stata valutata in frutti di pomodoro di due cv commerciali
(Solanum lycopersicum L, cv Optima e cv Caramba). I frutti maturati in
presenza della radiazione UV hanno mostrato un arricchimento in fenoli
e flavonoidi, con conseguente aumento dell’attività antiossidante, e un
trend opposto per i carotenoidi. La sperimentazione ha inoltre evidenziato
una sostanziale invarianza tra i frutti maturati nei tunnel installati l’anno
precedente, a suggerire una riduzione della capacità di schermatura UV nel
corso delle due stagioni.UV radiation influences many aspects of plant metabolism, inducing, for
example, the production of protective compounds important for plants as well
as welfare and human health. The use of cover film with good transmittance
to UV radiation could allow the production of fruit and vegetables enriched
in these compounds. The influence of different cover films on the content of
phenolic compounds, flavonoids and carotenoids was tested in tomato fruits
of two commercial cv (Solanum lycopersicum L, cv and cv Optima Caramba).
Fruits ripened in the presence of UV radiation showed an enrichment in
phenols and flavonoids, with consequent increase of the antioxidant activity,
and an opposite trend for the carotenoids. The research also showed virtually
no change between fruits ripened in the tunnels installed the year before
the trial, suggesting a reduction in the ability of shielding UV during the two
seasons
- …
