Evaluation of physiological properties of grapevine clones of ‘Tempranillo’ and ‘Graciano’ in DOCa Rioja (Spain)
In order to avoid the loss of grapevine intra-varietal diversity of DOCa Rioja grape varieties, Regional Government of La Rioja established a germplasm bank with more than 1.600 accessions, whose origin lies in the prospecting and sampling of ancient vineyards located throughout the whole region. 30 clones of Tempranillo and 13 clones of Graciano were preselected and multiplied in a new vineyard for further observations. The aim of this work is to describe the first results from the physiological characterization by an optical sensor of these preselected clones, which constitute the base of a new clonal selection that aims to increase the range of available certified clones and to improve the adaptation of these varieties to future objectives and environmental conditions.
Candidate clones (30 cv. Tempranillo; 13 cv. Graciano) were planted in 2016 in an experimental vineyard in La Rioja (Spain). A complete randomized block design was set up with four replicates of 10 plants. In 2020, 2021 and 2022 clones were evaluated with DUALEX® handheld sensor at flowering and veraison. DUALEX® is a leafclip meter that can accurately determine the chlorophyll and flavonols contents in leaves. It also provides the NBI® (Nitrogen Balanced Index), a good indicator of plant nitrogen status. Besides, in 2022, clones were measured with Crop Circle ACS 430 TM handheld sensor to determine NDVI index (vigour) of each clon. These sensors are mainly used for abiotic stress studies.
These optical sensors were able to identify significant differences between the biotypes, proving to be interesting tools for fast phenotyping of grapevine physiological and vegetative characteristics. The results obtained confirmed therefore the huge wide genetic variability existing between the clones. The diversity found in the levels of chlorophylls, flavonols and nitrogen could be used in future clonal selection programs.
Issue: ICGWS 2023
Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, Universidad de La Rioja, CSIC). Finca La Grajera, Ctra. de Burgos Km. 6, Logroño, La Rioja 26007, Spain
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intra-varietal diversity, climate change, clonal selection, genetic erosion, chlorophyll, NBI