Whatever the news, the vine does not wait! itk’s customer support team continues the measurements in the field, especially before sunrise.
The role of this customer support team is to support customers – consultants and distributors – throughout the season. It is also responsible for carrying out field measurements to validate or evolve the agronomic models of itk. 

 

Sampling and measurements in the vineyards, before sunrise

In April 2020, Basile Ploteau and Vincent Hitte carried out weekly soil sampling on plots of vines belonging to Vintel® users. Since the end of May, they have been carrying out pressure chamber measurements on these same plots.

The pressure chamber allows us to measure the water potential of the plant. As part of our activities, we perform this measurement before sunrise, when perspiration is very reduced and the tension of the sap in the plant tends to balance with that of the soil water. Our measurement protocol is very strict” says Basile Ploteau.

 

Vincent Hitte indicates the leaf water potential, measured with the pressure chamber

The support team plans three to four sessions of measurements in the season, depending on the phenological stages and the climatic conditions of the vintage: a first measurement at knotting in the dry years; then at cluster closure; at mid-veraison and at maturity. This year, Basile and Vincent had to adapt to keep pace after a warm and humid spring, which generated a phenological advance.

Vincent explains “We plan the measurement sessions according to the weather forecast, as pressure chamber measurements do not have to be done during or up to four days after rain or irrigation. We prefer the cool and windless nights, in order to promote the water balance between the plant and the soil. Not to mention the need to respect the deadlines of re-entry on the plot treated. We have to constantly adjust our schedule and our travel.”

 

Measurement of the basic leaf water potential with the pressure chamber

Sampling consists of six healthy leaves over six separate feet, with a similar level of vigour. The sampling areas are marked with rubalise, in order to be re-used during subsequent sessions. The leaves are selected on the lower part of the primary twigs. They are first bagged and then taken at the level of their insertion on the twig. “We have to be precise and fast in our gestures,” says Vincent, who adds “After having detached the leaf, we cut the cutter at about one centimeter from the tip of the petiole to obtain a clean section. Then we place the sheet in the sealed chamber, leaving only the end of the petiole protruding. The key to success is to increase the pressure in the chamber, very gradually, to avoid measurement errors. When the sap is flushed with the petiole, the gas supply is stopped immediately. The pressure displayed on the pressure gauge corresponds to what is called the “basic” water potential, which is measured before sunrise.”   This data is directly available on the Vintel® main interface.

All field measurements for the 2020 season are part of an internal agronomic monitoring project. The plots studied were chosen to be representative of the sectors covered by the Vintel® solution: more or less low organic matter soils; different grape varieties and production objectives; different driving modes (trained vines vs. cups, worked soil vs. grass).

Itk’s customer support team has five people who maintain close relationships with users of our services. This technical monitoring is essential for a good understanding of the user need.