Search results for "GC"

Chemical composition and herbicidal activity of the essential oil from a Cistus ladanifer population from Spain

2012

[EN] The essential oil composition of Cistus ladanifer grown in central Spain was analysed by gas chromatography and gas chromatography/mass spectrometry, revealing it to be rich in oxygenated compounds, with trans-pinocarveol (20.00%), bornyl acetate (7.03%) and terpinen-4-ol (6.37%) as the main monoterpene compounds. Viridiflorol (13.59%) and ledol (4.36%) were the main constituents of the oxygenated sesquiterpene fraction. Large amounts of-pinene (4.70%) were found in the hydrocarbonated fractions. To study its possible use as a natural herbicide, the oil was tested invitro against Amaranthus hybridus, Portulaca oleracea, Chenopodium album, Conyza canadensis and Parietaria judaica, compl…

Leaf epicuticular waxes effects egg parasitoid’s response to host adult footprint contact kairomone

2009

Chemical footprints left behind by true bugs are perceived as a contact kairomones by scelionid egg parasitoids. In the system Nezara viridula and its egg parasitoid Trissolcus basalis, previous studies have shown that the kairomone mediating such behavior is part of N. viridula’s cuticular hydrocarbons. In this study, the effect of epicuticular waxes of leaves of broad bean, Vicia faba, on wasp response to footprints of N. viridula females are investigated. Plants with intact waxes layer were used (1) without host chemical contamination, or (2) contaminated by host female footprints. Mechanically de-waxed plants were tested (3) without host chemical contamination, or (4) de-waxed a few min…

Indagini di laboratorio sui composti che inducono l'aggregazione delle neanidi di I età in Leptoglossus occidentalis (Hemiptera, Coreidae)

2011

Leptoglossus occidentalis è una cimice che si alimenta degli strobili e dei semi delle conifere appartenenti alla famiglia delle Pinaceae. Le neanidi di I età hanno un comportamento gregario che favorisce la sopravvivenza degli individui, in analogia a quanto visto in altre specie appartenenti allo stesso genere (Wheeler et al., 1990). L’individuazione dei composti semiochimici che influenzano questo comportamento potrebbe portare allo sviluppo di nuovi metodi di controllo di L. occidentalis. Le estrazioni (whole body) sono state realizzate su gruppi di 7-27 neanidi di I età per 30 minuti utilizzando un quantitativo di 40µl di esano o di acetone per neanide. Gli estratti sono stati biosaggi…

Il feromone sessuale a breve raggio del parassitoide oofago Trissolcus brochymenae

2009

Il comportamento sessuale dei parassitoidi presenta una fase di pre-copula, in cui si ha ricerca, corteggiamento e riconoscimento dell’altro sesso, alla quale seguono le fasi di copula ed eventualmente post-copula. Durante la pre-copula, la localizzazione e il riconoscimento sono per lo più stimolati da composti feromonali con diversa volatilità. I composti feromonali ad alta volatilità, rilasciati dalle femmine, sono utilizzati dai maschi per l’orientamento a lunga distanza, mentre quelli scarsamente volatili mediano il comportamento di corteggiamento. In questo lavoro si riportano dati sperimentali sul feromone sessuale a breve raggio emesso dalle femmine di Trissolcus brochymenae (Hymeno…

Sexual communication in the egg parasitoid Trissolcus brochymenae

2009

The males of the egg parasitoid Trissolcus brochymenae (Hymenoptera Scelionidae) exploit a short range pheromone for recognition of the other gender. To evaluate the role of this pheromone, the behavior of virgin males has been studied in closed arena when exposed to the following cues: 1) virgin females (alive, dead "washed" with solvents, dead" unwashed"); 2) dissected and re-assembled virgin females (females dissected into head, mesosoma, and gaster, then reassembled using two solvent "washed" parts and an "unwashed” part, or "unwashed" legs assembled with entire" washed" body); 3) "washed" females treated with acetone extracts (of virgin females and of legs). Males antennate and mount v…

Modifications over time of volatile compounds in coriander (Coriandrum sativum L.)

2007

Coriander (Coriandrum sativum L.) is an annual strongly-smelling herb belonging to the family Apiaceae, which is cultivated all over the world for its aromatic fruits (“seeds”) and, in many Asiatic and South American countries, for its green leaves. The aromatic features of leaves and fruits are sharply different, and the strong smell coming from leaves (many times referred to as a “bug” scent) is not always pleasant to many consumers from western countries. In our work, one Coriander small-seeded biotype has been grown in plastic covered greenhouses, and at given time intervals samples of leaves, flowers and fruits have been analyzed by means of HS-SPME and GC-MS to study the evolution ove…

Variations in the volatile compounds of a Fennel (Foeniculum vulgare Mill.) variety grown in a semi-arid Mediterranean environment

2005

Fennel is an industrial source of anethole but, recently, further interest has came from the suggested possibility of many industrial uses of this plant. The volatile substances from the seeds of fennel grown in Sparacia (Cammarata - AG - Sicily; 37° 38' N; 13° 46' E) have been investigated and compared on a statistical base with previously reported data. The variety grown in Sparacia fall into the "high fenchone" chemovariety. The substances alpha-toluene, alpha-terpinene, beta-phellandrene + limonene and camphene appear the components most sensitive to environment and grow condition modifications. Fennel is an industrial source of anethole but, recently, further interest has come from the…

Influence of "single-origin" coffees on sensory characteristics of Espresso.

2004

I funghi nella Strategia Globale per la Conservazione delle Piante

2009

I funghi, nonostante siano inseriti in un Regno a parte, sono stati riconosciuti come organismi utili per la definizione di alcune azioni nell’ambito della GSPC (Global Strategy for Plant Conservation). Con l’inserimento del termine generico di “lower plants groups” si è lasciata libera scelta ai Paesi che hanno aderito alla GSPC di valutare l’opportunità di estendere alle crittogame le azioni già in atto per le piante vascolari. Come evidenziato nel recente rapporto sullo “Stato della Biodiversità in Italia” (1) la diversità dei funghi è quantificabile in 4.296 basidiomiceti, tra cui 56 taxa con possibili caratteristiche di endemicità, 12 taxa esotici e 87 rari, minacciati e/o a rischio di…

Screening of Ovarian steroidogenic pathway in Ciona intestinalis and its modulation after Tributyltin exposure

2010

In this study, we have identified several ovarian steroids in Ciona with high similarity to vertebrate steroids and showed that cholesterol, corticosterone, dehydroepiandrosterone, estrone, estradiol-17beta, testosterone, pregnenolone, progesterone, have identical molecular spectra with vertebrate steroids. In addition, we have studied the effects of an endocrine disruptor (tributyltin: TBT) on these sex hormones and their precursors, ovarian morphology, and gene expression of some key enzymes in steroidogenic pathway in the ovary of Ciona. Ovarian specimens were cultured in vitro using different concentrations of TBT (10{sup -5}, 10{sup -4} and 10{sup -3} M). Ethanol was used as solvent co…