Impact of contrasting soils in a high-altitude vineyard of <i>Vitis vinifera</i> L. cv. Malbec: root morphology and distribution, vegetative and reproductive expressions, and berry skin phenolics

Abstract

The high-altitude viticulture of Mendoza is being increasingly recognised among the top wine regions worldwide. High levels of solar ultraviolet-B (UV-B) radiation, alluvial heterogeneous soils and cool night temperatures are major influences on Vitis vinifera L. phenotypic characteristics, especially on Malbec, Argentina’s emblematic grapevine variety. In the present work, the effect of intra-vineyard contrasting soil depth on Malbec was evaluated in a high-altitude vineyard (1450 m a.s.l.), over two growing seasons for physiological traits and over three vintages for yield components and berry skin phenolic compounds. The experiment was carried out in two parcels of shallow (SS) and deep (DS) soils, with different physico-chemical characteristics, and submitted to equal irrigation and crop management. Results showed that root depth was not limited by any soil physical constraints and fine roots (&lt; 1 mm) were patchily distributed in sites with higher contents of silt, clay and organic matter in SS. Higher root quantity in SS was related to lower vegetative and reproductive expressions, shorter ripening period and reduced berry size and fruit yield when compared to DS. When SS plants experienced mild water stress (ΨS, stem water potential, between -6 and -9 bar) increments of anthocyanins, total polyphenols and antioxidant capacity in berry skins were observed. However, when SS plants reached ΨS ≤ -10 bar, physiological harm occurred. The results presented contribute to understanding the effects of soil type on Malbec vines during different seasonal environmental conditions, especially in stressful situations, such as those expected by climate change scenarios.

Classification of Cabernet Franc Wines from Different Geographical Indications of Mendoza, Argentina, by Descriptive Sensory Analysis and Phenolic Profiles

“…Normally, poor soils such as those analyzed in GUA contribute to more stressful conditions that trigger the synthesis of some phenolic compounds. This GI has very heterogeneous soils with some difficulty in defining horizons, being a short soil that makes it more frequently exposed to water stress, contributing to the increase of phenolic compounds content according to Mezzatesta et al…”

“…37 Normally, poor soils such as those analyzed in GUA contribute to more stressful conditions that trigger the synthesis of some phenolic compounds. This GI has very heterogeneous soils with some difficulty in defining horizons, being a short soil that makes it more frequently exposed to water stress, contributing to the increase of phenolic compounds content according to Mezzatesta et al 38 The results of the anthocyanin profiles showed some individual anthocyanins associated with different GIs (Figure 1a). Many anthocyanins were higher in GUA, compared to the rest of the GIs (Table 1).…”

Rootstocks Alter the Seasonal Dynamics and Vertical Distribution of New Root Growth of Vitis vinifera cv. Shiraz grapevines

“…Noble had shallow roots, with approximately 35% of the total roots in the 0-15 cm depth whereas most of the roots of Dogridge occurred in the 90-105 cm soil profile. Mezzatesta et al [51] indicated that root depth was not limited by soil conditions, but the distribution of fine roots was uneven in areas with more silt, clay, and organic matter in shallow soil. More roots distribution in shallow soil led to reduced plant growth, shorter ripening time, and smaller berries and fruit yield compared to deep soil.We found that new root production by 140 Ruggeri occurred in the 0-52 cm layer with the greatest root numbers between 10-30 cm.…”