Pruned vine biomass exclusion from a clay loam vineyard soil – examining the impact on physical/chemical properties

Downy mildew, a disease caused by Plasmopara viticola (Berk. et Curt.) Berl. and De Toni, is one of the strongest threats to grapevine (Vitis vinifera L.) production. Recently, sources of resistance to downy mildew were identified among Caucasian germplasm. Among them, the Georgian variety Mgaloblishvili revealed a unique resistance mechanism. A genome wide association study (GWAS) allowed the identification of the genetic bases of Mgaloblishvili resistance, the loci Rpv29, Rpv30 and Rpv31. To dissect the three resistance loci, Mgaloblishvili genome was sequenced using PacBio HiFi reads and assembled.

For cool windy climates and/or lower vigor site situations delays in vine development during vine establishment can result in a greater number of growing seasons to achieve full yield potential. Plant material and training strategies utilized are critical factors in promoting vine development and production that is appropriate to the site conditions. The objective of this study was to evaluate nursery planting stock and training strategies for their potential to achieved advanced vine development and yield.

Regionality, frequently called terroir, is often used to market wines from different locations. Savatiano (Vitis Vinifera L.), is the dominant indigenous variety of the Mesogeia – Attiki region, reaching a percentage of 70% of the total vine cultivation, and being the most widely planted variety in Greece. In this context, this research focuses on the evaluation of the impact of different terroirs within the PGI Attiki zone on the aromatic profile of Savatiano.

To alter the vineyard microclimate and produce quality wine under a semi-arid climate, black geotextile inter-row mulch (M) was applied for two vintages (2016-2017). The grapes were sampled at three growing stages to conduct the untargeted metabolome and transcriptome analysis. The upregulated genes related to photosynthesis and heat shock proteins confirmed that M weakened the total light exposure and grapes suffered severe heat stress, resulting in lower sugar and higher acids at harvest. The integration of metabolome and transcriptome analysis identified the key genes responsible for the enhancements in phenylalanine, glutamine, ornithine, arginine, and C6 alcohol concentrations, and the downward trend in ε-viniferin, anthocyanins, flavonols, terpenes and norisoprenoids concentrations in M grapes.

Australian grape producers are facing a difficult wine market, therefore a reduction of vineyard production costs is critical.