Ferran Camp

Innovative LIDAR 3D Dynamic Measurement System to Estimate Fruit-Tree Leaf Area

In this work, a LIDAR-based 3D Dynamic Measurement System is presented and evaluated for the geometric characterization of tree crops. Using this measurement system, trees were scanned from two opposing sides to obtain two three-dimensional point clouds. After registration of the point clouds, a simple and easily obtainable parameter is the number of impacts received by the scanned vegetation. The work in this study is based on the hypothesis of the existence of a linear relationship between the number of impacts of the LIDAR sensor laser beam on the vegetation and the tree leaf area. Tests performed under laboratory conditions using an ornamental tree and, subsequently, in a pear tree orchard demonstrate the correct operation of the measurement system presented in this paper. The results from both the laboratory and field tests confirm the initial hypothesis and the 3D Dynamic Measurement System is validated in field operation. This opens the door to new lines of research centred on the geometric characterization of tree crops in the field of agriculture and, more specifically, in precision fruit growing.

Advances in pesticide dose adjustment in tree crops

Recently, there have been several attempts to introduce new pesticide dosing methods for fruit orchards and vineyards. However, in Southern Europe, these new methods have not been adopted. This is mainly because farmers lack confidence in the new methods. This lack of confidence partly results from the failure of the new dosing methods to take into account tree leaf density. For this reason, the most common dosing method is the traditional one which is used to control the concentration of the pesticide solution to be sprayed. In this context, farmers tend to spray a greater volume than is necessary and therefore frequently overdose their orchards. A method for estimating the Leaf Area Index was developed. This methodology was then implemented in a decision support system and validated over four seasons, 2009-2012. The decision support system allowed significant reduction in the volume of pesticide sprayed while maintaining the same level of biological efficacy. This system could provide the basis of a universal dose method for pesticide spraying in tree crops.

Spray application volume test in apple and pear orchards in Catalonia (Spain) and Variable Rate Technology for dose adjustment.

The adjustment of spray application conditions is still an issue in spray applications in fruit crops. Many fruit varieties are found in apple and pear orchards, that can be in different development stages and grown in a wide range of training systems. The active ingredient of a pesticide preparation can be delivered using different volume application rates (VAR), which if not well adjusted to each orchard can cause a diminution of the application efficiency. The objective of the work was to decide the best VAR in two apple varieties (Golden and Red Chief) and two pear varieties (Blanquilla and Conference). During two growing seasons, three VAR (400, 800 and 1600 l/ha) were tested in different orchards. Spraying parameters were kept as similar as possible (sprayer, forward speed, droplet size, air volume rate, weather conditions, etc.) so that the differences were mainly caused by the tested VAR. Depending on the results, there was a possibility to design and test a variable rate (VR) sprayer prototype able to deliver an specific flow rate according to the volume of vegetation detected by ultrasonic sensors. According to the results, no clear trends were found between the three different VAR, although it seems that the lowest VAR could be more suitable for early season spraying, whereas in full stage applications the highest VAR seemed more adequate. The fact that the same droplet size and a last generation sprayer were always used can explain why no differences between the corresponding spray deposits were found. The results found led us to develop and validate the VR prototype turning out into very optimistic results on dose adjustment in real-time.