Organic mulches slightly influence wine phenolic composition and sensorial properties

Grapevine rootstocks provide protection against environmental biotic and abiotic stresses. Nitrogen (N) and iron (Fe) are growth-limiting factors in many crop plants due to their effects on the chlorophyll and photosynthetic characteristics. Iron nutrition of plants can be significantly affected by different nitrogen forms through altering the uptake ratio of cations and anions, and changing rhizosphere pH. The aim of this study was to investigate the response mechanisms of grapevine rootstocks due to the interaction between different nitrogen forms and iron uptake.

Atypical aging (ATA) is a white wine fault characterized by the appearance of notes of wet rag, acacia blossoms and naphthalene, along with the vanishing of varietal aromas. 2-aminoacetophenone (AAP) – a degradation compound of indole-3-acetic acid (IAA) – is regarded as the main sensorial and chemical marker responsible for this defect. About the origin of ATA, a stress reaction occurring in the vineyard has been looked as the leading cause of this defect. Agronomic, climatic and pedological factors are the main triggers and among them, drought stress seems to play a crucial role.[1]

Secondary (or specialised) metabolites such as terpenes and phenolic compounds are produced by plants for various roles which include defence against pathogens and herbivores, protection against abiotic stress, and plant signalling. Additionally, these metabolites influence grapevine quality traits such as colour, aroma, taste, and nutritional value. However, the biosynthesis of these metabolites is often complex and controlled by multiple genes which in grapevine are predominantly uncharacterised.

Grapevine trunk diseases (GTD) occur wherever grapes are grown and are considered the main biotic factor reducing yields and shortening vineyards’ lifespan. Currently, no product is available to eradicate GTD once grapevines are infected. Therefore, prophylactic strategies based on pruning wound protection and ‘remedial surgery’, the only eradication method based on the elimination of infected wood and renewal of the vine by means of new canes or suckers, are the only effective strategies available. The Canadian grape and wine industry focusses on a sustainable production and thus, looking for alternatives to chemicals for disease management is a top priority.

Rootstocks not only provide tolerance to Phylloxera, but also ensure the supply of water and mineral nutrients to the whole plant. Rootstocks are an important way of adapting to environmental conditions while conserving the typical features of scion varieties. We can exploit the large diversity of rootstocks used worldwide to aid this adaptation. The aim of this study was to characterise rootstock regulation of scion mineral status and its relation with scion development.