Field assessment of a newly-designed pneumatic spout to contain spray drift in vineyards: evaluation of canopy distribution and off-target losses.

Background: The efficacy and environmental sustainability of pesticide application largely depend on maximizing target coverage, while minimizing off-target losses. Recently, laboratory-based measurements were used to develop new cannon-type spout to increase the droplet size spectra produced by a pneumatic vineyard sprayer. The study described below evaluated the effectiveness of the new device to reduce off-target losses (both in-field and off-field ground losses), and to distribute an adequate canopy spray.

Assessment of the Accuracy of a Multi-Beam LED Scanner Sensor for Measuring Olive Canopies.

Canopy characterization has become important when trying to optimize any kind of agricultural operation in high-growing crops, such as olive. Many sensors and techniques have reported satisfactory results in these approaches and in this work a 2D laser scanner was explored for measuring canopy trees in real-time conditions. The sensor was tested in both laboratory and field conditions to check its accuracy, its cone width, and its ability to characterize olive canopies in situ.

Assessing the influence of air speed and liquid flow rate on the droplet size and homogeneity in pneumatic spraying.

Background: The efficacy of treatments in vineyards largely depends on the necessary balance between leaf coverage and spray drift and, therefore, knowledge about droplet size is of major importance, but scarce scientific information is available on pneumatic spraying, often adopted in this crop. The objective of this work was to obtain the relationships between the droplet size spectra characterization parameters and the main affecting factors in pneumatic nozzles.

Results: Three liquid flow rates (LFR) and four air speeds (AS) were combined in laboratory conditions to assess their influence on the droplet size spectra (D10, D50 and D90), homogeneity (Relative Span Factor, RSF) and driftability (V ) in two different air shear nozzles (cannon-type and hand-type nozzles).

First attempts to obtain a reference drift curve for traditional olive grove's plantations following ISO 22866.

The current standard for the field measurements of spray drift (ISO 22866) is the only official standard for drift measurements in field conditions for all type of crops, including bushes and trees. A series of field trials following all the requirements established in the standard were arranged in a traditional olive grove in Córdoba (south of Spain). The aims of the study were to evaluate the applicability of the current standard procedure to the particular conditions of traditional olive trees plantations, to evaluate the critical requirements for performing the tests and to obtain a specific drift curve for such as important and specific crop as olive trees in traditional plantations, considering the enormous area covered by this type of crop all around the world.

Testing the Suitability of a Terrestrial 2D LiDAR Scanner for Canopy Characterization of Greenhouse Tomato Crops.

Canopy characterization is essential for pesticide dosage adjustment according to vegetation volume and density. It is especially important for fresh exportable vegetables like greenhouse tomatoes. These plants are thin and tall and are planted in pairs, which makes their characterization with electronic methods difficult.

Influence of liquid-volume and airflow rates on spray application quality and homogeneity in super-intensive olive tree canopies.

Olive is a key crop in Europe, especially in countries around the Mediterranean Basin. Optimising the parameters of a spray is essential for sustainable pesticide use, especially in high-input systems, such as the super-intensive hedgerow system. Parameters may be optimised by adjusting the applied volume and airflow rate of sprays, in addition to the liquid to air proportion and the relationship between air velocity and airflow rate.

Towards an optimized method of olive tree crown volume measurement.

Accurate crown characterization of large isolated olive trees is vital for adjusting spray doses in three-dimensional crop agriculture. Among the many methodologies available, laser sensors have proved to be the most reliable and accurate. However, their operation is time consuming and requires specialist knowledge and so a simpler crown characterization method is required.

Testing accuracy of long-range ultrasonic sensors for olive tree canopy measurements.

Ultrasonic sensors are often used to adjust spray volume by allowing the calculation of the crown volume of tree crops. The special conditions of the olive tree require the use of long-range sensors, which are less accurate and faster than the most commonly used sensors. The main objectives of the study were to determine the suitability of the sensor in terms of sound cone determination, angle errors, crosstalk errors and field measurements.