Les séminaires ont lieu sur le Campus Montpellier SupAgro/INRA de La Gaillarde (2, place P. Viala Montpellier)
Jeudi 15 mars 2012
Amphi 206 (Cœur d’Ecole) à 14h
Reserves dynamics of grapevines and the implications for grape production
Research Theme Leader, National Wine & Grape Industry Centre, New South Wales, Australia
The production and storage of carbohydrates in grapevines is influenced by vineyard management and climatic conditions. Stored carbohydrate reserves support early shoot growth and there is also evidence that the availability of reserves may influence reproductive development, including grape composition. The productivity level and the period after harvest determine the replenishment of carbohydrate reserves for the following season. The research focused on the understanding of the carbohydrate reserve dynamics (within and between seasons) and the influence of cultural practises on reserves in relation to vine development and grape production The general pattern of seasonal reserve utilisation is characterized by a decrease following bud-break, and then an increase that can begin any time between flowering and leaf-fall. Our work has shown that the amount of reserves stored prior to leaf-fall can be influenced by management practices, and that these may alter vigour, yield and grape composition in the following season. However, the scope to alter carbohydrate reserve storage through cultural practice does not substantially alter the seasonal pattern of reserve dynamics. This suggests that developmental stage or seasonal climatic factors have a stronger influence on carbohydrate mobilization and storage. The manipulation of reserve accumulation through cultural practice change may be more suited to effecting longer-term adjustments in vine productivity than short term responses to seasonal yield fluctuations. The assessment of winter carbohydrate reserves could become an important tool to determine changes in viticultural intervention requirements. Climate variability and change can influence the reserve accumulation and mobilisation. For instance, warmer root temperatures in spring can elevate the mobilisation of root reserves, while a longer and warmer period after harvest can increase winter reserve accumulation. We are in the process of undertaking further research on above and below ground environment on carbohydrate reserve dynamics in relation to vine development and grape composition.
Contact : Anne Pellegrino