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Kaolin effect on fresh and canned clingstone peach fruit quality and inorganic element composition Texte intégral
2015
Maletiska, P. A. | Nanos, G. D. | Stravroulakis, G. G.
Recently, kaolin sprayable materials are studied and used with many crops to control insects and diseases, alleviate heat stress and reduce sunburn damage. Furthermore, kaolin has been found to positively affect fruit external and internal quality with various fruit species. We investigated the effect of kaolin particle film application on fresh and canned clingstone peach fruit quality and inorganic element composition. Kaolin was applied periodically from early July to early August 2010 on ‘Andross’ peach trees. Fresh peach fruit treated with kaolin and harvested at commercial maturity (middle of August) had increased flesh firmness (FF), soluble solids content (SSC) and acidity and lower water content (WC) compared to control fruit. Kaolin presence on fresh peach fruit skin did not affect L*, but decreased a* compared to control fruit even after kaolin removal with water. In addition, kaolin-treated fresh peach fruit had similar P, K, Ca, Mg, Fe, Mn, Zn, Cu, Na, Cd, and Ni and slightly lower Pb contents compared to control peach fruit, while Co and Cr were not detected. Canned peach fruit had modified quality compared to fresh fruit, but most of the differences in quality attributes between kaolin-treated and control fruit remained after canning. Peach fruit color was similar in the two treatments after peeling and canning. Finally, the processed peach fruit treated with kaolin had decreased P, K, Mg, Fe, Mn, Zn, Cu, Ni and similar Ca, Na, Cd, Pb contents compared to processed control fruit, while Co and Cr were not detected. It seemed that certain nutrients leaked from the kaolin-treated processed peach fruit to the syrup resulting in decreased SSC and inorganic element content in the processed peach halves compared to the fresh kaolin-treated fruit.
Afficher plus [+] Moins [-]Semiochemicals of Rhagoletis Fruit Flies: Potential for Integrated Pest Management Texte intégral
2015
Sarles, Landry | Verhaeghe, Agnès | Francis, Frédéric | Verheggen, François | Entomologie fonctionnelle et évolutive
peer reviewed | Worldwide economic losses associated with Rhagoletis fruit flies (Diptera: Tephritidae) require an effective means of control. Most conventional insecticides used to control fruit flies have been banned, and fruit producers are seeking new economical fruit fly control options. Bait stations can be a suitable alternative, provided they are affordable, effective and pest-specific. Semiochemicals are important for fruit flies to locate their host fruit and to reproduce. They could therefore be good candidates to improve existing bait stations. In this literature review, we summarize the available data on Rhagoletis semiochemicals, including the pheromones and allelochemicals used for host location. Then, we present some field applications of semiochemicals that have been successful at Rhagoletis fly control and discuss potential semiochemical-based control strategies. | Développement d'une méthode de lutte alternative contre la mouche du brou du noyer, Rhagoletis completa
Afficher plus [+] Moins [-]Three variegated Clementines obtained by irradiation Texte intégral
2015
Kafa, Gucer | Seday, Ubeyit | Uysal, Onur | Polatoz, Sefa
Three variegated ‘Clementine’ mutants were selected at the Alata Horticultural Research Station of Mersin among the M1V3 ‘Clementine’ plants obtained from budwood Gamma ray irradiation at 30 gray. Young fruit rind color is attractively variegated but fruit rind color variegation fades with maturity and mature fruit rind color could easily masquerade as an ordinary ‘Clementine’. The young fruit rind is striped green and orange, but mature fruit rind has ridges. Seed number per fruit is reduced compared to the ‘Clementine’ control plants and vary between 7.5 and 13.07. Fruit weight are 72.73, 69.3 and 80.94 g, respectively, for variegated Clementine No.1, 2 and 3 and 110.10 g for control ‘Clementine’ plants. Other pomological characteristics are the same for variegated and control plants.
Afficher plus [+] Moins [-]Benzyladenine and Gibberellin Applications Improve Fruit Weight and Delay Maturity of Sweet Cherry | Verbesserung des Fruchtgewichtes und Reifeverzögerung bei Süßkirschen durch die Applikation von Benzyladenin und Gibberelline Texte intégral
2015
Canli, Fatih Ali | Pektas, Mustafa | Ercisli, Sezai
Fruit size has special importance for small-fruited early maturing cherry cultivars. In this study the effects of pre-harvest benzyladenine (BA) and BA plus gibberellin (GA) applications on fruit size and quality of ‘Noir de Guben’ sweet cherry (Prunus avium) were evaluated. ‘Noir de Guben’ trees were sprayed to run off with BA (50, 100 and 150 ppm) and BA + GA₄₊₇(12.5, 25, and 50 ppm) at straw-yellow color stage of the fruit. Fruit treated with BA (50, 100 and 150 ppm) and BA + GA₄₊₇(25 and 50 ppm) were significantly heavier and larger than the control. BA and BA + GA₄₊₇applications did not affect fruit firmness and fruit pH. 50 ppm BA-treated fruit had higher SSC (Soluble Solid Content) than control fruit. Excluding 25 ppm BA treatments, all treated fruit had higher acidity than the control fruit. BA and BA + GA₄₊₇applications delayed skin color development of the treated fruit. ‘Noir de Guben’ trees treated with the optimum concentrations of BA (150 ppm) and BA + GA₄₊₇(50 ppm) yielded fruit with 16.84 and 10.6 % greater weight, respectively.
Afficher plus [+] Moins [-]Effect of 1-MCP on cactus pears stored at 20°C Texte intégral
2015
D'Aquino, S. | Schirra, M. | Palma, A. | Satta, D. | De Pau, L. | Lovicu, G. | Chessa, I.
This study was carried out to assess the effect of 1-methylcyclopropene (1-MCP), an inhibitor of ethylene receptors, on physiological activity and quality traits of cactus pears. Fruit of the first crop were exposed to 400 ppb 1-MCP at 20°C for 24 h and then stored at 20°C and 60% RH for 2 weeks. Treated fruit showed significant increases in respiration activity, ethylene production rates at the end of the treatment with respect to control fruit; thereafter both respiration activity and ethylene production decreased with values constantly slightly higher in 1-MCP treated fruit than control fruit. 1-MCP hastened fruit ageing, stimulated detachment of the piece of cladode left at harvest at the stem end and slightly increased transpiration rate. The exposure to 1-MCP made the fruit more susceptible to microbiological spoilage; after 2 weeks of storage decay incidence in treated fruit was 16% while in control fruit was 11%. Based on results of this study, 1-MCP does not seem a suitable means to improve the shelf-life of cactus pears.
Afficher plus [+] Moins [-]Semiochemicals of Rhagoletis fruit flies: Potential for integrated pest management Texte intégral
2015
Sarles, Landry | Verhaeghe, Agnès | Francis, Frédéric | Verheggen, François J.
Worldwide economic losses associated with Rhagoletis fruit flies (Diptera: Tephritidae) require an effective means of control. Most conventional insecticides used to control fruit flies have been banned, and fruit producers are seeking new economical fruit fly control options. Bait stations can be a suitable alternative, provided they are affordable, effective and pest-specific. Semiochemicals are important for fruit flies to locate their host fruit and to reproduce. They could therefore be good candidates to improve existing bait stations. In this literature review, we summarize the available data on Rhagoletis semiochemicals, including (1) the kairomones involved in fruit location, (2) mating and sex pheromones and (3) oviposition and host marking pheromones. We present the latest data on the chemical composition of these semiochemicals, as well as some field applications that have been successful at Rhagoletis fly control. Based on the available data on the semiochemicals of Rhagoletis species and other Tephritid flies, we believe that the association of an efficient food attractant with early applications of host marking pheromones could reduce the risk of oviposition that usually occurs rapidly after emergence. Also, traps baited with sex pheromones and/or fruit-associated kairomones could attract and kill emerging individuals. However, analytical work has still to be conducted, as most Rhagoletis semiochemicals have yet to be identified.
Afficher plus [+] Moins [-]Harvest and postharvest quality of sweet cherry are improved by pre-harvest benzyladenine and benzyladenine plus gibberellin applications Texte intégral
2015
Fatih Ali Canli | Murat Sahin | Sezai Ercisli | Ozgur Yilmaz | Nurettin Temurtas | Mustafa Pektas
This study was carried out to evaluate the effects of pre-harvest benzyladenine (BA) and BA plus gibberellin (GA4+7) treatments on fruit quality attributes of ‘0900 Ziraat’ cherry at harvest and after cold storage. ‘0900 Ziraat’ cherry trees were sprayed with BA (50, 100, and 150 mg·L–1) and BA + GA4+7 (12.5, 25, and 50 mg·L–1) when fruit was at their straw-yellow color stage. All of the treated fruit were significantly firmer than control fruit. Fruit treated with 25 and 50 mg·L–1 BA + GA4+7 and 50 and 150 mg·L–1 BA had significantly higher soluble solids content (SSC) than untreated fruit. Sweet cherry trees treated with the optimum concentration of BA + GA4+7 (50 mg·L–1) yielded fruit with 15.17 % greater weight, 9.0 % higher firmness and 13.6 % higher SSC. Additional samples were harvested, placed in plastic bags, and stored at 4 °C for 30 days. At the end of the cold storage period, fruit treated with 25 and 50 mg·L–1 BA + GA4+7 and 50 and 150 mg·L–1 BA were significantly firmer than the control. 50 mg·L–1 BA + GA4+7 -treated fruit had higher SSC than untreated ones. In conclusion, fruit treated with the optimum dose of BA + GA4+7 (50 mg·L–1) were larger and firmer than untreated fruit at harvest and this concentration had the best effects. Most of the treated fruit maintained a superior firmness and quality to control fruit during cold storage.
Afficher plus [+] Moins [-]Evaluation of a systems approach to control Queensland fruit fly (Bactrocera tryoni)in stonefruit as an alternative to fenthion Texte intégral
2015
Missenden, Brendan | Senior, Lara J. | Bilney, K. | Wright, Carole L.
Queensland fruit fly (Bactrocera tryoni) is a significant quarantine pest of stonefruit. To access domestic markets within Australia stonefruit require treatment to ensure they are free of fruit flies. Due to the recent restriction of the organophosphate pesticides, fenthion and dimethoate, the stonefruit industry now faces a significant challenge to control fruit flies. In this field trial we quantified the level of control achieved by a 'best case' systems approach that relied on currently available and registered control measures. This system included protein bait sprays, Male Annihilation Technique, insecticide cover sprays of trichlorfon, maldison and spinetoram and inspection and culling of damaged fruit. We found that in two out of the three trial orchards, packed fruit samples from Gatton (QLD) and Bangalow (NSW) had low levels of fruit fly infestation; 1.47 and 2.97% respectively. However, at the third property located at Alstonville (NSW) a high level of infestation (51.63%) was found in packed nectarines, which was likely attributed to the late implementation of the systems approach. This trial has demonstrated the potential for fruit fly control without relying on fenthion, however further modification of the system is needed to refine and increase efficacy.
Afficher plus [+] Moins [-]Osobine ploda sorti dunje u beogradskom Podunavlju / Fruit characteristics of quince cultivars in the region of Belgrade Texte intégral
2015
Radović, Aleksandar (Poljoprivredni fakultet, Beograd-Zemun (Srbija)) | Nikolić, Dragan (Poljoprivredni fakultet, Beograd - Zemun (Srbija)) | Milatović, Dragan (Poljoprivredni fakultet, Beograd-Zemun (Srbija)) | Đurović, Dejan (Poljoprivredni fakultet, Beograd-Zemun (Srbija)) | Đorđević, Boban (Poljoprivredni fakultet, Beograd-Zemun (Srbija))
This paper presents the results of four-year study (2010‡2013) of the fruit physical and chemical characteristics of eight quince cultivars in the region of Belgrade. Control cultivar for comparison was ‘Leskovacka’. All cultivars were characterized by significantly higher fruit weight and dimensions compared to the control cultivar. The shape of the fruit of most cultivars was round, which is the most suitable for processing. Most of the tested cultivars has exceeded the control in terms of fruit quality. Among tested quince cultivars, ‘Triumph’, ‘Morava’ and ‘Asenica’ can be recommended for growing in the region of Belgrade.
Afficher plus [+] Moins [-]Effects of kaolin-based particle film and fruit zone netting on Cabernet Sauvignon grapevine physiology and fruit quality Texte intégral
2015
Lobos, G. A. (Gustavo A.) | Acevedo-Opazo, César | Guajardo-Moreno, Alejandro | Valdés-Gómez, Héctor | Taylor, James A. | Laurie, V Felipe
Effects of kaolin-based particle film and fruit zone netting on Cabernet Sauvignon grapevine physiology and fruit quality Texte intégral
2015
Lobos, G. A. (Gustavo A.) | Acevedo-Opazo, César | Guajardo-Moreno, Alejandro | Valdés-Gómez, Héctor | Taylor, James A. | Laurie, V Felipe
Aims: Long exposure to high temperatures or UV-radiation may induce negative effects on vine physiology and grape composition. Here, the effects of two methods to moderate radiation and temperature in the fruit zone of a Cabernet Sauvignon vineyard were evaluated against a control. Methods and results: The treatments assessed were: (a) periodical spraying of kaolin on leaves and bunches and (b) fruit zone netting with a Raschell’s type mesh. The kaolin-based treatment increased the reflectance of light and moderately reduced fruit temperature (~1ºC below the control), whilst the shading net caused a significant reduction in radiation and temperature in the fruit zone (~7ºC below the control). The Net treatment showed lower (more negative) stem water potential values than the control, but did not persist until the end of the trial. Also, none of the treatments led to significant changes in stomatal conductance, transpiration or CO2 assimilation throughout the season. However, the incidence and severity of fruit dehydration was significantly lower in the treated plants compared to the control. Finally, no differences in fruit chemical composition were observed between the treatments and the control. Conclusion: Under the conditions of this trial, both treatments tested were sufficient in moderating the negative effects of excess radiation or high temperature on grape berries. Significance and impact of the study: Kaolin-based particle spraying and fruit zone netting were proved to be feasible practical alternatives to lessen the negative effects of excess radiation or high temperature on grape berries, under hot climate.
Afficher plus [+] Moins [-]Effects of kaolin-based particle film and fruit zone netting on Cabernet Sauvignon grapevine physiology and fruit quality Texte intégral
2015
Gustavo A. Lobos | César Acevedo-Opazo | Alejandro Guajardo-Moreno | Héctor Valdés-Gómez | James A. Taylor | V. Felipe Laurie
Aims: Long exposure to high temperatures or UV-radiation may induce negative effects on vine physiology and grape composition. Here, the effects of two methods to moderate radiation and temperature in the fruit zone of a Cabernet Sauvignon vineyard were evaluated against a control. Methods and results: The treatments assessed were: (a) periodical spraying of kaolin on leaves and bunches and (b) fruit zone netting with a Raschell’s type mesh. The kaolin-based treatment increased the reflectance of light and moderately reduced fruit temperature (~1ºC below the control), whilst the shading net caused a significant reduction in radiation and temperature in the fruit zone (~7ºC below the control). The Net treatment showed lower (more negative) stem water potential values than the control, but did not persist until the end of the trial. Also, none of the treatments led to significant changes in stomatal conductance, transpiration or CO2 assimilation throughout the season. However, the incidence and severity of fruit dehydration was significantly lower in the treated plants compared to the control. Finally, no differences in fruit chemical composition were observed between the treatments and the control. Conclusion: Under the conditions of this trial, both treatments tested were sufficient in moderating the negative effects of excess radiation or high temperature on grape berries. Significance and impact of the study: Kaolin-based particle spraying and fruit zone netting were proved to be feasible practical alternatives to lessen the negative effects of excess radiation or high temperature on grape berries, under hot climate.
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