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Serra S.,University of Sassari | Mannoni M.A.,University of Sassari | Ligios V.,University of Sassari | Fiori P.P.,AGRIS Sardegna Agricultural Research Agency of Sardinia
Phytopathologia Mediterranea | Year: 2011

The occurrence of Phaeomoniella chlamydospora was investigated during vine propagation in an Italian nursery, and combined hot water (HWT) and cyproconazole treatments were carried out to limit the spread of the fungus in nursery vines. In the three-year period 2005-2007, cutting and graft samples (scion cv. Sangiovese, rootstock cv. 140Ru in 2005 and 1103P in 2006-2007) were taken during propagation at several infection risk stages, and the occurrence of P. chlamydospora was assessed by nested PCR. In 2005 and 2006, cuttings from esca-symptomatic grapevines (scion cv. Sauvignon blanc, rootstock cv. 140Ru in 2005 and 1103P in 2006) were treated at different stages of the propagation process. In 2007, artificially infected 1103P cuttings were treated with HWT and cyproconazole after being inoculated with P. chlamydospora, and the fungus was detected by isolation on agar medium. The effect of HWT on the growth of 1103P, 779P, Sangiovese and Cabernet franc cuttings was also assessed. Despite extended wood discoloration, P. chlamydospora was scarce in nursery vines during the three-year period. The contamination of planting material may have resulted from already infected mother plants (0.0 to 6.7% of infected cuttings) or may have started during the propagation, particularly after grafting (0.0 to 23.3% of infected grafts). Canes from esca-diseased mother plants were always infected, but the incidence of infection of the cuttings varied widely (about 30% in 2005, from 1.9 to 4.1% in the other years). However, no final conclusions could be drawn about the stage or stages at which the nursery vines mainly became infected, because the infection frequencies detected in the propagation process were too low and irregular. As regards control of P. chlamydospora, HWT of cuttings performed before or after cold storage influenced plant growth, depending on both the cultivar and the growing conditions, but HWT was harmful to callused graftlings. Natural contamination of nursery material in 2005 and 2006 was insufficient to allow the effectiveness of treatments to be assessed. In 2007, HWT and cyproconzole alone did not reduce the percentage of infection in artificially inoculated cuttings. Only cyproconazole immediately followed by HWT significantly reduced the number of infected cuttings, but this procedure did not eradicate the pathogen.

Todaro M.,University of Palermo | Dattena M.,AGRIS Sardegna Agricultural Research Agency of Sardinia | Acciaioli A.,University of Florence | Bonanno A.,University of Palermo | And 5 more authors.
Small Ruminant Research | Year: 2015

Aseasonal or out-of-season milk production for small ruminants raised in Mediterranean areas refers generally to milk having to be produced at a time that corresponds to summer which is when conditions are generally unfavourable with respect to both physiological aspects and nutritional factors related to seasonal climatic trends. In fact, sheep and goat milk production in the Mediterranean basin is mostly based on pasture utilization and thus follows the pasture availability pattern. This causes a strong seasonal pattern to the amount of milk processed by cheese processes plants, with the peak being in the spring, a marked reduction in early summer and nil or low availability of milk from August to October-November (autumn). In this paper, the reproduction cycles and managerial techniques that can be applied in the Mediterranean environment to reduce or eliminate the seasonality of milk production are discussed. The use of the "ram effect" at the end of the anoestrous season and light treatment can be effective and simple tools to maintain milk yield in the summer period. However, even if sheep and goats are considered to be among the most heat-tolerant species, the exposure to high ambient temperatures has a detrimental impact on their production and reproductive performances, immune function and udder health. The use of effective nutritional strategies, the provision of shaded areas and adequate housing density could then reduce the heat stress. © 2015 Elsevier B.V.

Sitzia M.,AGRIS Sardegna Agricultural Research Agency of Sardinia | Bonanno A.,University of Palermo | Todaro M.,University of Palermo | Cannas A.,University of Sassari | And 3 more authors.
Small Ruminant Research | Year: 2015

Sheep milk production in summer can lead to a diversification of milk products and to a more regular product distribution in the market throughout the year. However, in Mediterranean countries small ruminant production cycles are subjected to seasonal variations in forage resources. During summer, a key period for out of season production systems, nutrition plays a fundamental role in regulating the quantity and quality of milk production. In this review, feeding strategies and techniques that could be applied for out of season production in dairy ewes under different Mediterranean conditions are described for intensive, pasture-based and mixed systems. The most common feeding strategies used during the dry season are based on grazing post-harvest by-products or forage produced under irrigation. The criteria used to choose the appropriate forage species and to optimize the grazing technique are discussed here. In addition, types of forages and feeding techniques to be adopted for indoor systems, along with a series of feed supplements best suited to cope with heat stress, are described. The influence of feed resources and environmental conditions on milk and cheese production are also discussed. Overall, in order to be cost-effective, out of season sheep milk production systems must take into consideration the availability and price of feed resources, especially supplements, and irrigation costs. It is concluded that out of season milk production could be adopted primarily by farms with highly productive breeds, access to irrigated lands and appropriate management skills. © 2015 Elsevier B.V.

Fernandes de Oliveira A.,University of Sassari | Mameli M.G.,AGRIS Sardegna Agricultural Research Agency of Sardinia | de Pau L.,AGRIS Sardegna Agricultural Research Agency of Sardinia | Satta D.,AGRIS Sardegna Agricultural Research Agency of Sardinia | Nieddu G.,University of Sassari
South African Journal of Enology and Viticulture | Year: 2013

The effect of deficit irrigation strategies on physiological performance, growth, source:sink balance, water productivity and berry composition of field-grown grapevines of flhis vinifera L. cv. Cannonau (syn. Grenache)/1103P were investigated in Sardinia, Italy, in 2009. In two of the treatments, both sides of the root system received 50% and 25% crop evapotranspiration (ETc), referred to as strategies DI50 and DI25, respectively. In the third treatment, which included partial root-zone drying (strategy PRD), ETc was set at 50%. All three treatments were compared to a full irrigation control (strategy Fl), thus 100% ETc. No severe water stress was imposed from berry development onwards. Strategies DI25 and PRD induced higher stomatal closure and leaf water-use efficiency. A slightly higher net assimilation rate was recorded in H before véraison. During ripening, leaf area decreased in DI50 and DI25, but lateral shoots continued to grow in Fl and P1U. Yield and pruning weight were higher in Fl, but in all the treatments the vines were source:sink balanced and supported ripening. Irrigation water productivity was higher in DI25, and no significant differences in yield or water productivity were observed between PRI) and DI50 irrigated with a similar volume of water. Full irrigation produced berries with a significantly higher fresh and dry weight, lower °Brix and higher malic acid at harvest, while PRD berries weighed less and had less titratable acidity, lower phenol content and a higher pH. Total anthocyanin contents were consistently lower in DI25 and PRD, with highest values measured in DI50. The treatments showed different anthocyanin proffles, with a higher concentration of acylated anthocyanin in DI25 and PRD.

Piras F.,AGRIS Sardegna Agricultural Research Agency of Sardinia | Lovicu G.,AGRIS Sardegna Agricultural Research Agency of Sardinia | Zurru R.,AGRIS Sardegna Agricultural Research Agency of Sardinia
Acta Horticulturae | Year: 2014

Seven cultivars of table grapes were observed with the goal of getting more news about the characteristics of the cultivation, focusing on the evolution of vegetative-productive buds as a function of position along the branch to use. The observations focused on the vitality of the buds and the number of shoots and bunches products. Cultivars 'Michele Palieri', 'Italia' and 'Red Globe' appeared fairly balanced with regard to fertility that is evenly distributed on the vine. In 'Italia' grape the high percentage of blind buds on the top positions of the vine could be a problem for the identification of the branches of replacement. Cultivars 'Victoria' and 'Black Magic', which are characterized by a high fertility index, can be trained with a shorter number of buds per branch. Instead 'Sublima seedless' and 'Superior seedless', due to low fertility index, need canes with a high number of buds. The different agronomic characteristics of the cultivars highlighted the need of a differentiation in the technical approach for planting patterns and pruning (winter and green).

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