3D thematic maps of the chemical parameters of orange fruits

Abstract

Since orange is the most produced and consumed fruit in Brazil and since its position on the tree may influence its physical and chemical attributes, current assay modeled a three-dimension spatial variability of total soluble solids (TSS) and ascorbic acid (AA) contents of the fruit in an orange orchard according to fruit position (coordinates x, y and z) on the plant and analyzed solar radiation on them. The experiment was conducted in Nova Laranjeiras, Paraná State, Brazil, and analyzed 715 fruit (Monte Parnaso variety) from nine trees in 2011, 2012 and 2013. Results showed that high TSS contents were reported in the tree´s peripheral area in the two analyzed thirds due to a high solar radiation. Highest AA rates were reported in the apical third. In the case of quadrants, higher AA levels were found in SE and NE (morning sun) with regard to the apical third and in SW and SE (afternoon sun) with regard to the basal third. The three-dimension interpolation method displays the spatial variability of the fruit´s physical attributes by three-dimensional maps.