Spraying quality using unmanned aerial vehicle in citrus

Abstract

This study aimed to evaluate the effect of the operating flight height of an unmanned aerial vehicle with different spray tip rotations on the parameters of droplet coverage, density and volumetric median diameter of the sprayed droplets, in acid lime culture ´Tahiti’. The experiment was performed in randomized blocks design, with repetition within the block, in a factorial system (3x2), with four repetitions. Three planting lines were selected for each treatment. The two outer lines were used as borders and the central one for evaluation. In each treatment, one plant was selected from the planting line and four water-sensitive papers were fixed in the middle third of the outermost portion of the canopy.A solution containing water and a drift reducing adjuvant was prepared to analyze the quality of the spray. A significant difference was found for the variables of spray tip rotation and flight height with no interaction between them. This result indicates that these variables act independently on the volumetric median diameter values. Furthermore, the spray heights of 3.0 m and 4.0 m have a notable effect on the amount of deposition. However, their influence on droplet size is negligible.

Efficiency of Fungicide Application an Using an Unmanned Aerial Vehicle and Pneumatic Sprayer for Control of Hemileia vastatrix and Cercospora coffeicola in Mountain Coffee Crops

“…The mean coverage, density, and deposition of droplets significantly increase as the application rate is increased. Similar results were found in similar experimental studies on conilon coffee [5], arabica coffee [6], citrus [24,25], apple [2,3], wheat [17], and rice [16] crops. Two aspects are considered important for fungicide application to coffee arabica crops using a UAV: the first is the low operational capacity due to the limited tank load and low battery charge duration [15,29] and the second is the characteristic place of infestation of most fungal diseases in conilon coffee crops, which is usually in the middle and upper canopy layers [30,31]; the results indicate the use of an application rate of 10 L ha −1 .…”

“…The answer to this question depends on the investigation of operational parameters of UAV, such as the application rate, operational flight speed and height, and droplet positioning and distribution on the crop canopy. Experimental applications using a UAV for spraying pesticides on specific crops are found in scientific articles, with applications to grass crops, such as rice [15,16], wheat [17,18], maize [19], and sugarcane [20], and to shrub and arboreal crops, such as cotton [21], peach [22], apple [23], citrus [24,25], and coffee [5,8]. These experimental applications to coffee crops are limited to operational aspects, disregarding the efficacy of possible pesticides in the applications.…”

Impact of Operational Parameters on Droplet Distribution Using an Unmanned Aerial Vehicle in a Papaya Orchard

“…Furthermore, the downwash effect contributed to the penetration and distribution of the drops on the plants, i.e., the air flow generated by the multi-rotors agitates the leaves on the plant canopy, facilitating the deposition process, especially in the lower layer [18,45]. Despite providing lower values in the upper and middle layers, compared to the XR110015 nozzle, the MGA015 nozzle displayed better droplet distribution in the lower layer and on the papaya fruit clusters, indicating possible control of pests and diseases located in this region.…”