Evaluation of the Intelligent Sprayer System in Peach Production

Abstract

Air-blast sprayers are routinely used to apply pesticides in commercial peach orchards, with growers using both conventional air-blast and ultrasonic sensor driven models. Even with advanced spray technologies, there are still concerns with the amount of chemicals used and lost to drift. Our study evaluated a LIDAR-based variable rate sprayer system in three experimental peach orchards for pest and brown rot disease control, spray volume output, spray coverage, and spray drift. A single 378 L air-blast sprayer was used for both , the conventional air-blast and the Intelligent Sprayer (iSprayer) treatments. Treatments were started at the phenological stage of bloom and continued through final swell. The iSprayer treatment was as effective in controlling pests and brown rot disease as the conventional air-blast treatment. Compared to the conventional air-blast treatment, the iSprayer treatment reduced the spray volume (liter/hectare) in cultivar ‘PF23’ by 71% at bloom, 62% at pit hardening and 55% at final swell, respectively. For ‘Juneprince’ the spray volume reduction was 50% at bloom, 40% at pit hardening, and 13% at final swell, respectively. Spray drift was significantly (P<0.05) reduced only at bloom in the iSprayer treatment. Spray coverage was increased by 50.13% and 26.67% in the iSprayer treatment at bloom and pit hardening, respectively, but not at final swell. Our results show that the iSprayer maintained pest and disease control efficacy in peach orchards, while reducing spray volume and drift compared to the conventional air-blast treatment.

Opportunities and Possibilities of Developing an Advanced Precision Spraying System for Tree Fruits

“…In the last two–three decades, modern sprayers including tunnel sprayers, tower sprayers, and precision sprayers have allowed orchard growers to reduce off-target deposition of spray materials and drift. Of these, precision or intelligent sprayers equipped with sensing technology have shown great potential to reduce excessive chemical applications [ 16 , 26 ].…”

“…Boatwright et al [ 16 ] compared a LiDAR-based variable rate sprayer system with a conventional spraying approach for disease and pest control management in a peach orchard. They reported the LiDAR-based precision sprayer could have the same amount of control with chemical savings ranging from 13% to 50% at various phenological stages (i.e., bloom, pit hardening, and final swell) of the trees.…”

“…Although several groups of researchers have developed prototypes to change the application flow rate based on canopy structural parameters from different sensors, precision spraying in tree fruit orchards needs further development to deal with excessive chemical usages, improper spray depositions, and losses from chemical drift [ 16 ]. Real-time precision orchard sprayer development is a challenging endeavor due to outside, uncontrollable environmental conditions.…”

“…Although several studies have reported a significant amount of pesticide reduction during spraying, most of them evaluated their savings on a small scale or in fairly controlled environments that are not feasible to a large-scale orchard field. Additionally, despite the advanced spraying technologies available in the past few years, there are still concerns with the amount of chemicals used and lost to drift [ 16 ], requiring more advanced technology for spraying in the large scale orchards. Precision sprayers are commercially available for weed control and plant treatment in arable land.…”

Design and development of orchard autonomous navigation spray system

“…The leaves can rotate under the blowing of the centrifugal fan, and those of the fruit tree can be fully sprayed because of the air assistance of the air-driven sprayer ( Boatwright et al, 2020 ; Boatwright and Schnabel, 2020 ). In general, the effect is better than that of hydraulic atomization, making the way of wind assistance more frequently adopted in the orchard.…”