Evaluación en campo del trampeo masivo de la mosca mediterránea de la fruta con Tripack® como alternativa a los tratamientos cebo con malatión en huertos de cítricos

The mass trapping technique based on the use of the female-targeted attractant lure Tri-pack® as an alternative to malathion bait-spraying (control treatment) was tested in two citrus orchards in the North of Tunisia against the Mediterranean fruit fly Ceratitis capitata during 2006 and 2007. Results of mass trapping trials in 2006 and 2007 indicated that adult males Medfly captures showed reductions respect to control of 37.62% and 40.2% respectively in mandarin orange variety (Citrus reticulata) orchard compared to 36.48% and 47.29% in Washington navel orange variety (Citrus sinensis) field. Fruit damage assessment showed significant differences between the mass trapping with Tripack® and malathion bait-spraying techniques in the reduction of the percentage of fruit punctures. The percentage of punctured fruit at harvest was significantly different between the treated and the control field in 2006 and in 2007 in the mandarin orange orchard. Nevertheless, in the Washington navel orange orchard, the percentage of punctured fruit at harvest was significantly different between the treated and the control field only in 2006. Thus, results obtained from this study showed that the mass trapping technique based on the use of the female-targeted lure Tri-pack® could be involved as an appropriate strategy for the control of the Medfly and is as effective as malathion bait spraying treatment without leaving pesticide residues on fruit.Se probó en dos huertos de cítricos, en el norte de Túnez en 2006 y 2007, la técnica del trampeo masivo utilizando el atrayente de hembras Tri-Pack® contra la mosca mediterránea de la fruta, Ceratitis capitata como alternativa a los tratamientos cebo con malatión, que constituye la forma convencional de control utilizada por los agricultores y que se utilizó como tratamiento control. En 2006 y 2007, en los ensayos de trampeo masivo las capturas de machos adultos del insecto se redujeron respecto el control, respectivamente, un 37,62% y un 40,2% en la variedad de mandarina (Citrus reticulata) en comparación con un 36,48% y un 47,29% en la variedad de naranja Washington navel (Citrus sinensis). Al evaluar los daños en los frutos se observaron diferencias significativas entre el trampeo masivo con Tripack® y los tratamientos cebo con malatión con una reducción de las picaduras en los frutos El porcentaje de frutos con picaduras en el momento de la cosecha fue significativamente diferente en las parcelas control y tratada en el huerto de mandarina tanto en 2006 como en 2007. Sin embargo, en el huerto de naranja Washington navel, el porcentaje de frutos con picaduras recolectados fue significativamente diferente entre el tratado y el control sólo en 2006. Por tanto, los resultados obtenidos en este estudio muestran que la técnica de trampeo masivo utilizando el atrayente de hembras Tri-Pack® podría ser una estrategia adecuada para el control de la mosca mediterránea de la fruta y es tan efectiva como el tratamiento cebo con malatión, pero sin dejar residuos de plaguicidas en la fruta

Screening of antioxidant potentials and bioactive properties of the extracts obtained from two Centaurea L. species (C. kroumirensis coss. and C. sicula L. subsp sicula)

Herbal medicines, dietary supplements, or infusions with health promoting effects can note strong consumer demand. Hence, researchers and scientists have been increasingly focusing on the promotion of medicinal plants. In this respect, the present study has the evaluation of the biological properties of different extracts (hexane, chloroform, methanol, ultrasonic, essential oil, and supercritical) obtained from two Centaurea species (C. kroumirensis (Coss.) and C. sicula L. subsp sicula) as purpose. Antioxidative activities were assessed by in vitro assays including total phenolic content, free radical scavenging assay and ferric ion reducing power. Among the fourteen extracts examined, the highest total phenolic content (TPC) and antioxidant abilities were recorded in ultrasonic ethanol extracts of both Centaurea species. Additionally, these extracts exhibited a noticeable strong protective effect of the human skin fibroblast cell line (HS-68) that was exposed to oxidative stress induced by hydrogen peroxide. According to our results, the sonication with ethanol might be an ideal, rapid, and eco-friendly extraction method for obtaining a polyphenol-rich extract that exhibited high antioxidant activity. The results presented herein suggest that Centaurea species could be promoted as an antioxidant resource that could be exploited for the development of nutraceuticals or in pharmacology industry

Effectiveness of pre-treatment method to hinder rebar corrosion in concrete

This paper aims to evaluate the ability of phosphate pretreatments applied on steel rebars to hinder the corrosion reinforcements using synthetic pore electrolyte and mortar contaminated by chloride ions. The electrochemical behaviour of the pretreated substrate was assessed by corrosion potential, polarisation resistance and electrochemical impedance spectroscopy measurements. The results have demonstrated that the treatment of the rebar by immersion in the Na3PO4 (0·5M) solution favours the formation of a passive layer on the steel rebar surface, which increases the resistance to corrosion initiation up to 0·3M Cl– instead of 0·1M Cl– without treatment. The pretreatment also provides enhancement of corrosion protection of the steel rebar in mortar. The evolution of the impedance spectra in function of chloride concentration is in a fairly good agreement with the results obtained from RP measurements

Volatile and phenolic contents and antioxidant and antibacterial properties of Tunisian milk thistle and mastic oils

The present study examined the chemical compositions as well as the antioxidant and antimicrobial activities of the vegetal oils of milk thistle (Silybum marianum) (MTO) and mastic (Pistacia lentiscus) (MO). The mastic oil extract was shown to have higher total phenolic and flavonoid contents than the oil extract of the milk thistle. The fatty acid and sterol compositions of the oil extracts were determined using gas chromatography coupled to flame ionization detection (GC-FID). The main fatty acids identified were palmitic, oleic, and linoleic acids. The main sterols found in milk thistle oil were beta-sitosterol and campesterol, followed by Delta-7-stigmastenol, stigmasterol, Delta-7-avenasterol, and Delta-5-avenasterol. The most abundant sterol in mastic oil was beta-sitosterol, followed by campesterol, Delta-5-avenasterol, and stigmasterol. The volatile compounds of the two vegetal oils were evaluated by headspace solid-phase microextraction (HS-SPME). In both oils, monoterpenes and non-terpenes were found to be the dominant volatile compounds in the mastic and milk thistle vegetal oils. 1,8-Cineole, methylpyrazine, 2,5-dimethylpyrazine, and hexanal were found to be the major volatile compounds of milk thistle oil, whereas myrcene and alpha-pinene were the major volatile compounds found in mastic oil. The antioxidant activities of the oil extracts were evaluated using various methods, such as DPPH, the ferric reducing power, the iron-chelating effect, and the beta-carotene bleaching assay. In all methods, mastic oil exhibited a higher activity than milk thistle oil. Furthermore, both oils exhibited antibacterial activity, but mastic oil was the most potent, particularly against Gram-negative bacteria. Given their high total phenolic and flavonoid contents, the presence of volatile bioactive compounds, and their sterol and fatty acid compositions, the two oil extracts possess high potential for pharmaceutical and cosmetic applications and for utilization as natural preservative ingredients in food

Field evaluatin of Mediterranean fruit fly mass trapping with Tripack as alternative to malathion bait-spraying in citrus orchards

The mass trapping technique based on the use of the female-targeted attractant lure Tri-pack® as an alternative to malathion bait-spraying (control treatment) was tested in two citrus orchards in the North of Tunisia against the Mediterranean fruit fly Ceratitis capitata during 2006 and 2007. Results of mass trapping trials in 2006 and 2007 indicated that adult males Medfly captures showed reductions respect to control of 37.62% and 40.2% respectively in mandarin orange variety (Citrus reticulata) orchard compared to 36.48% and 47.29% in Washington navel orange variety (Citrus sinensis) field. Fruit damage assessment showed significant differences between the mass trapping with Tripack® and malathion bait-spraying techniques in the reduction of the percentage of fruit punctures. The percentage of punctured fruit at harvest was significantly different between the treated and the control field in 2006 and in 2007 in the mandarin orange orchard. Nevertheless, in the Washington navel orange orchard, the percentage of punctured fruit at harvest was significantly different between the treated and the control field only in 2006. Thus, results obtained from this study showed that the mass trapping technique based on the use of the female-targeted lure Tri-pack® could be involved as an appropriate strategy for the control of the Medfly and is as effective as malathion bait spraying treatment without leaving pesticide residues on fruit.Se probó en dos huertos de cítricos, en el norte de Túnez en 2006 y 2007, la técnica del trampeo masivo utilizando el atrayente de hembras Tri-Pack® contra la mosca mediterránea de la fruta, Ceratitis capitata, como alternativa a los tratamientos cebo con malatión, que constituye la forma convencional de control utilizada por los agricultores y que se utilizó como tratamiento control. En 2006 y 2007, en los ensayos de trampeo masivo, las capturas de machos adultos del insecto se redujeron respecto el control, respectivamente, un 37,62% y un 40,2% en la variedad de mandarina (Citrus reticulata) en comparación con un 36,48% y un 47,29% en la variedad de naranja Washington navel (Citrus sinensis). Al evaluar los daños en los frutos se observaron diferencias significativas entre el trampeo masivo con Tripack ® y los tratamientos cebo con malatión con una reducción de las picaduras en los frutos El porcentaje de frutos con picaduras en el momento de la cosecha fue significativamente diferente en las parcelas control y tratada en el huerto de mandarina tanto en 2006 como en 2007. Sin embargo, en el huerto de naranja Washington navel, el porcentaje de frutos con picaduras recolectados fue significativamente diferente entre el tratado y el control sólo en 2006. Por tanto, los resultados obtenidos en este estudio muestran que la técnica de trampeo masivo utilizando el atrayente de hembras Tri-Pack® podría ser una estrategia adecuada para el control de la mosca mediterránea de la fruta y es tan efectiva como el tratamiento cebo con malatión, pero sin dejar residuos de plaguicidas en la fruta

Effectiveness of pretreatment method to hinder rebar corrosion in concrete

This paper aims to evaluate the ability of phosphate pretreatments applied on steel rebars to hinder the corrosion reinforcements using synthetic pore electrolyte and mortar contaminated by chloride ions. The electrochemical behaviour of the pretreated substrate was assessed by corrosion potential, polarisation resistance and electrochemical impedance spectroscopy measurements. The results have demonstrated that the treatment of the rebar by immersion in the Na3PO4 (0?5M) solution favours the formation of a passive layer on the steel rebar surface, which increases the resistance to corrosion initiation up to 0?3M Cl? instead of 0?1M Cl? without treatment. The pretreatment also provides enhancement of corrosion protection of the steel rebar in mortar. The evolution of the impedance spectra in function of chloride concentration is in a fairly good agreement with the results obtained from RP measurements.Peer reviewe