PHENOLOGICAL BEHAVIOR OF THE VINE (Vitis vinifera L.) CV. MALBEC IN ARGENTINE PATAGONIA. SEASONS 2008-09, 2009-10 Y 2010-11

Abstract

Phenology explains grapevine response to environmental conditions and allows predicting plant behaviour. The objective of this study was to advance in the knowledge of the terroir elements influence on the phenological performance of cv. Malbec in San Patricio del Chañar, a new wine-growing zone in the Argentine Patagonia. The study was carried out during 2008-09, 2009-10 and 2010-11 seasons in 38 sites arranged in three landscape units: old terrace, foothills and modern terrace, defined by edaphic variables. Weekly observations were made on four plants per site in order to determine sprouting, flowering, veraison and ripening dates, as well as the length of the sub-periods between them. Two analysis of variance with one and two variability factors were conducted for soil and phenological variables. A subsequent analysis of means comparison (Tukey 5% for soil variables and 1% for phenological variables) was also conducted using the Software R. The behavior of ‘Malbec’ was related to position in the landscape units as well as the climatic conditions and crop management, both integrated in the vintages effects. The seasonal effect was more marked than the landscape units effect. The cultivar developed its cycle in 130 days in both the old terrace and foothills, whereas this occurred in 134 days in the modern terrace, resulting in a later terroir. The sprouting-ripening cycle occurred in 119 days in the earliest season and in 139 days in the latest one. This was related to the yield per hectare and the temperatures recorded during the cycles under study.