Investigating the consequences of trimming and crop removal on soluble solids and titratable acidity for Sauvignon Blanc and Pinot Noir

Abstract

Trimming vines and crop removal are vineyard management practices grapegrowers use to manage yield, control vegetative growth and vigour. However, these techniques may impact on berry composition at harvest. Trimming and crop removal alter the source-sink balance of the vine: trimming removes leaves, reduces the source of photosynthates needed for berry ripening, while removing crop reduces the sink demand for photosynthates and other assimilates. Grape composition at harvest is a result of an accumulation or decrease in berry components throughout the ripening phase. It is important, therefore, to understand how trimming and crop removal alter the development of berry ripening. The time of trimming or crop removal may also influence the outcome. For example, lower total soluble solids (TSS) at harvest may be due to a slower rate of TSS accumulation, a delay in the start of ripening or both. Would trimming at veraison have the same effect and are other components such as titratable acidity also altered in the berry?