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Marras P.M.,Agricultural Research Agency of Sardinia | Cocco A.,University of Sassari | Muscas E.,University of Sassari | Lentini A.,University of Sassari
Biological Control | Year: 2016

Planococcus ficus (Signoret) is a key pest of grapevines and can cause severe crop losses in table and wine grape cultivars. In order to explore the potential of annual inoculative releases of Leptomastix dactylopii Howard against the vine mealybug, laboratory experiments were conducted to evaluate the suitability of P. ficus as a host for the parasitoid. The biological performance of L. dactylopii on P. ficus was examined in choice and no-choice tests, and compared with its performance on the primary host, Planococcus citri (Risso). Planococcus ficus supported complete development of the parasitoid with higher than 86% survival rates and a lower than 5% effective encapsulation. The low rates of encapsulation and host-feeding and high survivorship make P. ficus a suitable host for L. dactylopii in mass rearing facilities. In the choice test, parasitoids reared on P. ficus, or with prior oviposition experience on this species, preferred it over P. citri. Unexpectedly, parasitoids reared on P. citri, or with prior oviposition experience on this species, did not show any preference for either mealybug species. Our findings highlight a potential innate preference of L. dactylopii for the vine mealybug and indicate that this innate preference can be modified by the rearing host and early oviposition experiences. Thus, mass rearing of L. dactylopii on P. ficus would increase its preference for the target pest, with a positive impact on biological control programs against the vine mealybug. © 2016 Elsevier Inc. Source

Zinellu A.,University of Sassari | Zinellu A.,Porto Conte Ricerche S.r.l | Pasciu V.,University of Sassari | Sotgia S.,University of Sassari | And 10 more authors.
Analytical and Bioanalytical Chemistry | Year: 2010

We describe a new capillary electrophoresis laser-induced fluorescence (CE-LIF) method for the quantification of adenosine 5′-triphosphate (ATP) in spermatozoa and oocytes. The optimization of the precapillary derivatization reaction between ATP and 4,4-difluoro-5,7-dimethyl-4-bora-3a,4adiaza-s-indacene- 3-propionyl ethylene diamine hydrochloride (BODIPY FL EDA) has been described. BODIPY-ATP conjugate was analysed in an uncoated fused silica capillary of 75 μm ID and 50 cm effective length using a 10 mmol/L tribasic sodium phosphate buffer, pH 11.5, at 22 kV in <5 min. A good reproducibility of intra- and inter-assay tests was obtained (CV = 4.55% and 7.14%, respectively). With respect to our previous CE-UV assay, the new method showed an improvement in sensitivity that was about 120-fold (limit of quantification, 0.15 vs 18 μmol/L). Method applicability was proven on the reproductive cells of several animal species (roosters, horses, sheep and goats). Due to the elevated sensitivity, the new assay allows the measurement of adenosine 5′-triphosphate levels from just 20 oocytes. Considering that ATP concentration in reproductive cells is related to the mitochondrial integrity after cryopreservation, the proposed method could be a useful tool in assisted reproductive technologies. © 2010 Springer-Verlag. Source

Angioni A.,University of Cagliari | Dedola F.,Agricultural Research Agency of Sardinia | Garau A.,University of Cagliari | Sarais G.,University of Cagliari | And 2 more authors.
Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes | Year: 2011

Chlorpyrifos (O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphorothioate) was applied with three different formulations on oranges, peaches, tomatoes, wine and table grapes, and its behaviour was evaluated after field treatment. The formulations applied were emulsifiable concentrates (EC), microencapsulates (ME), and wettable granules (WG). The residues were similar in all crops studied in the EC and WG experiments, except peaches with WG treatment, the residue amount was lower than EC values. Tomatoes which were grown in greenhouse showed similar residues in all treatments just after treatment. Wine and table grapes showed different decline curves in the EC experiments ascribable to the different growing technology. Instrumental limit of determination (LOD) and limit of quantification (LOQ) for all matrices were 0.01, and 0.03mg kg -1, respectively. Repeated treatments showed that Chlorpyrifos can accumulate leading to residue levels at the preharvest interval (PHI) over themaximumresidue level (MRL), especially on oranges and peaches. Among the formulates used ME showed the higher risk of residues over the MRL at harvest. © Taylor & Francis Group, LLC. Source

D'Aquino S.,National Research Council Italy | Schirra M.,National Research Council Italy | Palma A.,National Research Council Italy | Satta D.,Agricultural Research Agency of Sardinia | And 3 more authors.
Acta Horticulturae | Year: 2015

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. © 2015, International Society for Horticultural Science. All rights reserved. Source

Pilichi S.,Agricultural Research Agency of Sardinia | Pool R.R.,Texas A&M University | Dattena M.,Agricultural Research Agency of Sardinia | Mara L.,Agricultural Research Agency of Sardinia | And 3 more authors.
BMC Veterinary Research | Year: 2014

Background: Articular cartilage has poor intrinsic capacity for regeneration because of its avascularity and very slow cellular turnover. Defects deriving from trauma or joint disease tend to be repaired with fibrocartilage rather than hyaline cartilage. Consequent degenerative processes are related to the width and depth of the defect. Since mesenchymal stem cells (MSCs) deriving from patients affected by osteoarthritis have a lower proliferative and chondrogenic activity, the systemic or local delivery of heterologous cells may enhance regeneration or inhibit the progressive loss of joint tissue. Embryonic stem cells (ESCs) are very promising, since they can self-renew for prolonged periods without differentiation and can differentiate into tissues from all the 3 germ layers. To date only a few experiments have used ESCs for the study of the cartilage regeneration in animal models and most of them used laboratory animals. Sheep, due to their anatomical, physiological and immunological similarity to humans, represent a valid model for translational studies. This experiment aimed to evaluate if the local delivery of male sheep embryonic stem-like (ES-like) cells into osteochondral defects in the femoral condyles of adult sheep can enhance the regeneration of articular cartilage. Twenty-two ewes were divided into 5 groups (1, 2, 6, 12 and 24 months after surgery). Newly formed tissue was evaluated by macroscopic, histological, immunohistochemical (collagen type II) and fluorescent in situ hybridization (FISH) assays. Results: Regenerated tissue was ultimately evaluated on 17 sheep. Samples engrafted with ES-like cells had significantly better histologic evidence of regeneration with respect to empty defects, used as controls, at all time periods. Conclusions: Histological assessments demonstrated that the local delivery of ES-like cells into osteochondral defects in sheep femoral condyles enhances the regeneration of the articular hyaline cartilage, without signs of immune rejection or teratoma for 24 months after engraftment. Source

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