Other Viticulture Services

Fig. 4 – Total aid received (left) and total integrated per agri-environmental measure (right).

The application of the model, after inclusion of the climate data and of qualitative information on phytosanitary pressure, presented for 2011 a yield potential with a clear downward trend compared with 2010. Thus the prediction interval is between 218 and 264 thousand barrels of must, representing a significant reduction (around 25-30%) compared with the yield potential predicted in 2010. The provisional IVDP data, resulting from production declarations, point to a reduction of around 23% in 2011.

8.2.4. Assessment of variety and rootstock behaviour

In this activity, data on the ripening and harvest characteristics of the scion/rootstock affinity block planted on Quinta da Cavadinha was monitored and collected. Information available in the DDR on varieties was also collected and processed, with special focus on phenological information to support the study of phenological relationships and their thermal requirements, to help draw up phenological maps to support viticultural management.

• The results were published in “Effects of the rootstocks and environment on behaviour of the cv Tinta Roriz in Douro Wine Region”; a study was also prepared based on the trials at Quinta da Cavadinha entitled

“Effects of rootstock and environment on Portuguese Grape varieties in Douro Region” submitted to the IX Congrès International des Terroirs Vitivinicoles (Dijon/Reims – to be presented in 2012).

8.2.5. Control of the grapevine moth using the mating disruption method

Protection against the grapevine moth using the mating disruption (MD) method has been studied by ADVID since 2000. Knowledge acquired over the course of a decade ensured the identification of strong points where its effectiveness can be maximised, as well as some restrictions that limit its use. In addition to the diffusion of knowledge acquired (through Technical Note No. 4 and the 2 colloquiums held), members with greater interest in the application of more sustainable means of protection against the grapevine moth asked ADVID for specialised support in this context, particularly in programming the application of dispensers in the field, in the training of technical personnel and agricultural workers of the company and other employees involved and in evaluation of the effectiveness of this means of control during the campaign, through monitoring of the moth damage both in locations subject to MD and in reference blocks (without MD). For this reason in 2011, following on from previous years, ADVID accompanied and provided specialised technical support to certain properties using this form of moth control.

The effectiveness of this method was evaluated by comparison of both the captures obtained in pheromone traps placed within the MD area and captures in a trap placed in a control area without dispensers, and damage occurring in both locations. The results obtained were the subject of extensive publicity at the workshops held, in specialised publications and in reviews of the viticultural year.

8.2.6. Study of the resistance of grapevine moth (Lobesia botrana) to the destemming and crushing process

In connection with the study Monitoring and Control of European Grapevine Moth, Lobesia botrana (2011-2012) underway in California under the orientation of Lucia Varela (UCCA Sonoma) and following the participation of ADVID in the 62nd ASEV (California-USA), where the strategies followed by ADVID to control the moth were presented, a collaboration was set up through the aforementioned study on the resistance of the grapevine moth to destemming and crushing. Measures for prevention and eradication of the pest in the USA require areas where the pest has been identified to be subject to obligatory control measures, which means the levels of presence are not sufficient for a study of this type. For this reason, ADVID in collaboration with the University of California has conducted research by way of provision of services in order to determine whether the moth would survive destemming and crushing processes, which was indeed confirmed, in the conditions in which the study was carried out.

8.2.7. Assessment of the effectiveness of treatments against grapevine powdery mildew during early stages of the growth cycle.

A trial was monitored on a block situated in Cima Corgo planted with Tinta Roriz, which is highly sensitive to this disease. The aim of this study was to assess the effectiveness of treatments starting at an earlier stage in the growth cycle. The positioning of the treatments was between budbreak and pre-flowering, at a 14-day rate, to control any primary infections at a stage of low efficiency of powdered sulphur due to low temperatures. Four groups were set up: 1 - Control; 2 - Application of 3 treatments with wettable sulphur before pre-flowering; 3 - Start of treatments at the “unfolded leaves” stage and another treatment during pre-flowering; 4 - Just one treatment at pre-flowering with an EBI. At the grape harvest, an assessment was made of the frequency of attack by recording incidence and severity in bunches. On the same block, an assessment was made of the evolution of the diseases of greatest importance in the region, this work being used to define the best positioning of treatments in accordance with meteorological data records.

• Also on this subject and for the purposes of disseminating results, a study entitled “Evaluation of the efficacy of first fungicide application on the control of Erysiphe necator and the ascospores release on Douro Region” was drawn up and submitted to the IOBC/WPRS Working Group “Integrated Protection and Production in Viticulture”, in Lacanau, Bordeaux. Partial results were also presented at workshops on the viticultural year.

8.3. Oenology

8.3.1. Ripening control

In addition to the immediate objective of providing members with ripening data on their own blocks, this initiative

also has a general aim of creating a database on the behaviour of the main varieties in the different sub-regions of the Douro.

Members participating in this initiative were provided with customised reports on the behaviour of their blocks, with regard to routine tests: Weight (g); Volume of liquid (mL); Potential alcohol (%); Total Acidity (mg/L Tartaric Acid) and pH; and Phenolic ripening: Total anthocyanins; Extractable anthocyanins; Total polyphenols (TP); Anthocyanin extractability - AE (%) and Tannin maturation - TM (%).

In 2011, 21 members and 2 non-members subscribed to this service, registering for the testing of ripening assessment on nearly 240 vineyard blocks, which took place between 19 July and 23 September 2011, 851 tests having been carried out. In addition, 148 ripening tests were carried out in ADVID trials, totalling 999 routine and phenolic tests processed in the laboratory.

Also in the field of ripening control services, in the context of the Annual Review of the Viticultural Year, a summary of the ripening of the reference varieties (Touriga Nacional and Touriga Franca) was drawn up. The ripening report for the DDR was not drawn up.

8.3.2. Tannin Portal (ADVID/AWRI)

The importance of knowledge of tannins in oenology, due to their influence on colour stability, on ageing of wines, on oxidation phenomena and on characteristics such as astringency, led ADVID to launch in July 2011, following contacts made with AWRI (Australian Wine Research Institute - a prestigious research institute with more than 50 years experience in wine science and industry), a tannin analysis service in partnership with AWRI, offering the analyses at a competitive price. In 2011, 4 members subscribed to this service, and around 500 analyses were made of samples received.