Modelling the Impact of Water Stress during Post-Veraison on Berry Quality of Table Grapes

Abstract

The aims of this work were modelling the effect of water stress intensity during post-veraison on table grape quality and yield, as well as predicting berry quality at harvest using a machine learning algorithm. The dataset was obtained by applying different irrigation regimes in two commercial table grape vineyards during seven growing seasons. From these data, it was possible to train and validate the predictive models over a wide range of values for the independent (water stress intensity and fruit load) and dependent (firmness and berry color) variables. The supervised learning algorithm Gaussian Process Regression allowed us to predict the variables with high accuracy. It was also determined that a reduction in irrigation of up to 40% during post-veraison, compared to vines without water limitations, and the accumulation of the water stress integral of up to 30 MPa per day, linearly increase the irrigation water use efficiency (IWUE) and promote higher berry color and firmness. The severe water scarcity and the increasing uncertainty about the irrigation water availability for the season that farmers are facing highlight the advantage of incorporating these validated techniques into agricultural decision making, as they allow for the planning of cultural practices and criteria to increase the IWUE and crop sustainability.

Quality Assessment and Ripeness Prediction of Table Grapes Using Visible–Near-Infrared Spectroscopy

“…Nonetheless, a notable increase in the a * values was not observed between stage I and II, indicating a gradual color change in grapes during this period. This phenomenon may be attributed to water stress resulting from dry weather conditions [ 33 ]. At the same time, the slow increase in red tones during the pre-color transition period is probably due to the low accumulation of monomeric anthocyanins during the ripening stage from I to II.…”

From Farm to Fork: Irrigation Management and Cold Storage Strategies for the Shelf Life of Seedless Sugrathirtyfive Table Grape Variety

“…These findings are in line with our data on grapes at harvest, for which TSSs and nutraceutical components were higher in SI, while berry weight and TA remained almost unchanged between NI and SI. In addition, Temnani et al [44] reported that reducing irrigation by up to 40%, particularly post-veraison, enhanced water use efficiency and increased berry color and firmness. SI grapes exhibited higher berry firmness at harvest than NI grapes, particularly for parameters such as Hardness, Chewiness and glyming.…”

Agronomic strategies to cope with wáter scarcity and increase the sustainability of mandarin tres under semi-arid conditions

“…Moreover, in late cultivars this period can last up to six months, thus increasing the potential for reducing pressure on water resources by deficit irrigation strategies . Nevertheless, when the irrigation thresholds described above are exceeded, it can affect productivity, vegetative growth, or fruit quality in the short or long term Blanco et al, 2019;Conesa et al, 2015;Temnani et al, 2022). The most widely validated indicator for determining trees water status is the stem water potential (Ψ s ), due to its high sensitivity to the irrigation regime, soil water status and evaporative demand Shackel et al, 1997).…”