Spatial variability of phenology in two irrigated grapevine cultivar growing under semi-arid conditions

Abstract

Knowledge and monitoring of the grapevine phenology during the season are important 13 requirements for characterization of productive regions, climate change studies and planning 14 of various production activities at the vine field scale. This work aims at studying the spatial 15 variability of grapevine phenology at the within field scale. It was conducted on two fields, 16 one of cv Cabernet Sauvignon of 1.56 ha and the other of cv Chardonnay of 1.66 ha, both 17 located in Maule Valley, Chile. Within each vine field, a regular sampling grid was designed, 18 to carry out weekly measurements of phenology and maturation. The main results show that 19 there is a significant spatial variability in the phenological development and maturation at 20 the within field scale for both fields. This variability is spatially organised and temporaly 21 stable from the beginning of the season (post-budburst) to harvest and over the years. A 22 cluster analysis allowed us to define two clearly contrasted zones in terms of phenology and 23 maturation in both fields, explained by the microclimate. The magnitude of difference 24 between zones varied from 4 to 9 days depending on phenological stages and from 5 to 43 25 days for maturation. These differences are similar and comparable to that observed at larger 26 scales or under scenarios of climate change. These results highlight the necessity to better 27 take into account this variability to improve sampling and to base decisions of production 28 activities (spraying, harvest, pruning, etc.) application on more relevant information. Further 29 investigations should determine the environmental factors that determine the observed spatial 30 variability.

Evaluation of a decision support strategy for the control of powdery mildew, Erysiphe necator (Schw.) Burr., in grapevine in the central region of Chile

“…Mandatory applications during the flowering‐setting period were the heart of the DSS. The timing of this application is key in disease control and requires a good estimate of phenology according to Verdugo‐Vásquez et al . This is especially true in highly heterogeneous fields characterised by topographical variations that influence the microclimate.…”

“…The Chardonnay and Cabernet Sauvignon fields were planted in 1994 and 1998, respectively, using own‐rooted plants with a spacing of 1.5 m between the vines and 3.0 m between the rows which were oriented east to west. The vines were trained in a vertical shoot position system with a total height above ground of 2.0 m. Other characteristics of the vine fields were presented by Verdugo‐Vásquez et al . The vines were irrigated using furrow irrigation, as recommended by Acevedo‐Opazo et al .…”

“…39 The Chardonnay and Cabernet Sauvignon fields were planted in 1994 and 1998, respectively, using own-rooted plants with a spacing of 1.5 m between the vines and 3.0 m between the rows which were oriented east to west. The vines were trained in a vertical shoot position system with a total height above ground of 2.0 m. Other characteristics of the vine fields were presented by Verdugo-Vásquez et al 40 The vines were irrigated using furrow irrigation, as recommended by Acevedo-Opazo et al 41 In the entire experimental vineyard, the shoots were topped and trimmed once a year. The vineyard was managed using standard agricultural practices for commercial vineyards in Central Chile (canopy management, fertilisation, pest and disease control, pruning and irrigation), which were similar throughout the three experimental seasons.…”

“…wileyonlinelibrary.com/journal/ps Mandatory applications during the flowering-setting period were the heart of the DSS. The timing of this application is key in disease control and requires a good estimate of phenology according to Verdugo-Vásquez et al 40 This is especially true in highly heterogeneous fields characterised by topographical variations that influence the microclimate. Attention must be drawn to the importance of using representative zones in the field to estimate the flowering time, in order not to delay a fungicide application that could negatively impact on proper control of the whole field.…”

GeoFIS: An Open Source, Decision-Support Tool for Precision Agriculture Data

“…Geolocalized data are effectively collected intensively within the fields by sensors embedded on agricultural machinery, satellites, flying platforms, static stations, or humans among others, to make sure that this variability is considered and accounted for [3][4][5]. Spatial data have particular characteristics that are worth careful consideration during analysis.…”