Management of cryptogamic diseases depends in part on the effectiveness of treatments. This relies on taking into account environmental factors as well as adapting and monitoring the equipment used. Such operations must be carefully monitored in order to reduce losses into the atmosphere (10 to 25%) and onto the ground (5 to 15%), which together can reach up to 40%, even when machines are correctly calibrated and adjusted.
2.5.2.a Selecting appropriate equipment for the type of treatment
Adapting the type of sprayer to the vines
At the beginning of the growth season in particular, it is advisable to adapt and optimize the spraying according to the volume of vegetation in order to reduce product consumption and drift. For this, the use of collection panels and closing nozzles that are not at the correct height for the vegetation are possible measures. There are also sprayers that are more suited to young vines, such as initial treatment booms, which can only be used on wide rows.
With backpack sprayers, a passage every other row is sufficient for the initial treatments since growth is not yet vigorous.
Adapting the nozzle to the treatment
There are several types of nozzles, which differ in part by their calibration, i.e. the size of the spray droplets. Below a certain size, about 250 microns, the droplets are more subject to drift, above 300 microns, they are more subject to runoff. Nozzles should be adapted to limit the drift of product in the air but also to maximize the coverage of the product on the plant and to limit its runoff due to the weight of the droplets.
Some products are more effective at a certain drop size. The effectiveness of spraying is based in part on the amount of active ingredient received per unit of plant surface to be protected. Depending on the product formulation, the ideal drop size may vary. For example, fine drops are preferred for a contact fungicide treatment, while fertilizers can be applied with a more variable drop size.