Programmable ultrasonic sensing system for targeted spraying in orchards.

This research demonstrates the basic elements of a prototype automated orchard sprayer which delivers pesticide spray selectively with respect to the characteristics of the targets. The density of an apple tree canopy was detected by PROWAVE 400EP250 ultrasound sensors controlled by a Cypress PSOC CY8C29466 microcontroller. The ultrasound signal was processed with an embedded computer built around a LPC1343 microcontroller and fed in real time to electro-magnetic valves which open/close spraying nozzles in relation to the canopy structure. The analysis focuses on the detection of appropriate thresholds on 15 cm ultrasound bands, which correspond to maximal response to tree density, and this was selected for accurate spraying guidance. Evaluation of the system was performed in an apple orchard by detecting deposits of tartrazine dye (TD) on apple leaves. The employment of programmable microcontrollers and electro-magnetic valves decreased the amount of spray delivered by up to 48.15%. In contrast, the reduction of TD was only up to 37.7% at some positions within the tree crown and 65.1% in the gaps between trees. For all these reasons, this concept of precise orchard spraying can contribute to a reduction of costs and environmental pollution, while obtaining similar or even better leaf deposits.

Effects of integrated and organic pest management with copper and copper-free preparations on tomato (Lycopersicum esculentum Mill.) fruit yield, disease incidence and quality.

The present study investigates the effect of exclusion of copper preparations from spray programs for disease control in integrated and organic tomato production systems on disease incidence, yield and fruit vitamin C, α-tocopherol and carotenoids content for Monroe, Optima and Paki cultivars. Open field trials were conducted in a randomized block system with four repetitions over two years. Treatment for plant disease control comprised four spraying programs, two within each production system. Yields were significantly affected by cultivar, pest management system and their interaction. Copper-free integrated and organic spraying programs were almost as effective in disease control as standard treatments which included copper preparations. The spraying program significantly affected the contents of vitamin C, α-tocopherol, phytoene, and ß-carotene in fruits; however, the effect was cultivar related. The lycopene contents appeared to be unaffected by the spraying program or growing system.