Abstract
In this research, a model for the estimation of antioxidant content in cherry fruits from multispectral imagery acquired from drones was developed, based on machine learning methods. For two consecutive cultivation years, the trees were sampled on different dates and then analysed for their fruits’ radical scavenging activity (DPPH) and Folin–Ciocalteu (FCR) reducing capacity. Multispectral images from unmanned aerial vehicles were acquired on the same dates with fruit sampling. Soil samples were collected throughout the study fields at the end of the season. Topographic, hydrographic and weather data also were included in modelling. First-year data were used for model-fitting, whereas second-year data for testing. Spatial autocorrelation tests indicated unbiased sampling and, moreover, allowed restriction of modelling input parameters to a smaller group. The optimum model employs 24 input variables resulting in a 6.74 root mean square error. Provided that soil profiles and other ancillary data are known in advance of the cultivation season, capturing drone images in critical growth phases, together with contemporary weather data, can support site- and time-specific harvesting. It could also support site-specific treatments (precision farming) for improving fruit quality in the long-term, with analogous marketing perspectives.
Highlights
According to Food and Agriculture Organization (FAO) data, the agricultural land cultivated with cherries exceeded 0.4 million hectares over the last decade (2007–2017), with slight upward trends, whereas world production reached 2.5 million tonnes
A single geodatabase was constructed for the entire study area and both cultivation seasons, in order to proceed with a common analytical view for the entire data set
The cherry plantations were digitized as polygon features, whereas the cherry trees were digitized as points fitting exactly to the centre of the trees as they were recognised in the Red Green Blue (RGB) images; the soil samples were digitized as points, too
Summary
According to Food and Agriculture Organization (FAO) data, the agricultural land cultivated with cherries exceeded 0.4 million hectares over the last decade (2007–2017), with slight upward trends, whereas world production reached 2.5 million tonnes. Greece ranks 12th in cherry production worldwide, with 100 thousand hectares, of which ~75% is in the Region of Central Macedonia, mainly in Pella and Imathia regional units [1]. Cherry cultivars of Greece belong to the species of Prunus avium, family Rosaceae. Cherry trees need a certain number of cold nights to break dormancy and bloom, and they prefer soils with pH levels between 6.0 and 6.8. Cherry fruits are rich in polyphenols, mainly flavonoids, flavanols and flavonols [3,4]. The colour of the crops depends on anthocyanin levels, a flavonoid compound, during maturation
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
