Terroir 2008 banner
IVES 9 IVES Conference Series 9 International Terroir Conferences 9 Terroir 2008 9 Climate component of terroir 9 The estimation of the clear-sky effective PAR resources in a mountain area

The estimation of the clear-sky effective PAR resources in a mountain area

Abstract

When evaluating the actual photosynthetically active radiation – PAR – resources available to plants the simple measurement or estimation of its total amount can lead to misleading interpretations, due to the frequent occurrence of radiation intensity above the light saturation threshold. In this case, besides the quantity of radiation, the use of other variables providing information on the temporal distribution of the resource (i. e. the insolation time) may be advisable. This work is an exploratory analysis of the effect of topography on the availability of PAR in an alpine viticultural region, the Aosta Valley, by the adoption of an index based on the summation over a given time period (in this specific case a day) of only the fraction of radiation effective for photosynthesis. Assuming clear-sky conditions, the resulting estimated maps widely differ from those of the total PAR, indicating spatial patterns closer to those of insolation time. The estimated ratios of “effective” to total PAR, assuming fully functional physiological conditions and fully developed canopies, vary from about 0.5 to 0.7 in the summer and from about 0.7 to 1 during the final ripening period; these values may be even lower in stress conditions.

DOI:

Publication date: December 8, 2021

Issue: Terroir 2008

Type: Article

Authors

O. Zecca (1), L. Mariani (2), O. Failla (2)

(1) Institut Agricole Régional, Rég. La Rochère, 1/A 11100 Aosta, Italy
(2) Dipartimento di Produzione Vegetale, Università degli Studi, via Celoria, 2, 20133 Milano, Italy

Contact the author

Keywords

solar radiation, PAR, climate data, viticultural zoning 

Tags

IVES Conference Series | Terroir 2008

Citation

Related articles…

Leaf vine content in nutrients and trace elements in La Mancha (Spain) soils: influence of the rootstock

The use of rootstock of American origin has been the classic method of fighting against Phylloxera for more than 100 years. For this reason, it is interesting to establish if different rootstock modifies nutrient composition as well as trace elements content that could be important for determining the traceability of the vine products. A survey of four classic rootstocks (110-Richter, SO4, FERCAL and 1103-Paulsen) and four new ones (M1, M2, M3 and M4) provided by Agromillora Iberia. S.L.U., all of them grafted with the Tempranillo variety, has been carried out during 2019. The eight rootstocks were planted in pots of 500 cc, on three soils with very different characteristics from Castilla-La Mancha (Spain). In the month of July, the leaves were collected and dried in a forced air oven for seven days at 40ºC. Then, the samples were prepared for the analysis determination, carried out by X-Ray fluorescence spectrometry. The results obtained showed that in the case of content in mineral elements in leaf, separated by soil type, we can report the importance of few elements such as Si, Fe, Pb and, especially, Sr. The rootstock does not influence the composition of the vine leaf for the studied elements that are the most important in determining the geochemical footprint of the soil. The influence of the soil can be discriminated according to some elements such as Fe, Pb, Si and, especially, Sr.

Functional characterisation of genetic elements regulating bunch morphology in grapevine

Vitis vinifera L., is considered one of the world’s most important cultivated fruit crops. In agriculture, bunch morphology is a grapevine-specific trait, which directly impacts fruit quality and health.
Bunch size, shape, and compactness are major aspects of bunch morphology, with the degree of compactness emerging as an important trait for grapevine genetic enhancement and vineyard management. The importance of this trait stems from its impact on disease susceptibility, berry ripening, and other grape quality properties. However, current knowledge of the genes controlling it remains limited.

Anthocyanin accumulation and extractability during the maturation of the grapes of three varieties

Anthocyanin accumulation and extractability were studied in Tannat, Cabernet Sauvignon and Merlot grapes produced in the south of Uruguay in two consecutive seasons. Typical cultivation situations employed in the region for each variety were considered. A follow-up was carried out, considering 60 plants per vineyard, and the harvest was determined according to the technological indices of maturity. Samples of grapes were taken in duplicate in each vineyard periodically along grape maturation. The basic composition, polyphenolic potential and anthocyanin extractability were determined. Also, half of grapes were frozen and later peeled; skin extractions over 24 hs with a solution of 12% ethanol and pH 3.2 were carried out. The anthocyanin contents of the extracts obtained were determined by HPLC-DAD. The levels of anthocyanins reached the highest values before technological maturity. Anthocyanin extractability had a decrease during grape maturation.

Hydroxycinnamic acids in grapes and wines made of Tannat, Marselan and Syrah from Uruguay

Background: hydroxycinnamic acids (HCA), present in pulp and skin of grapes, are relevant compounds in red winemaking

Study of the vine performance and the wine composition of Tannat on the terroir of Colonia del Sacramento – Uruguay

Grape-growing terroirs were defined according to the method proposed by Falcetti and Asselin (1996) near of Colonia de Sacramento, a city of Uruguay situated on the left of the “Rio de la Plata”.