Orchard`s soil characterization and nutrient mobilization to Rocha pear (Pyrus communis L.) fruits

Soil is a limited resource, being vital for plant production during the agricultural phase, and consequently a fundamental component of the agro-industrial sector. In a near future where efficiency in food production will be crucial to feed a growing population, agronomic strategies to ensure food quality needs to be tested and optimized with field trials. Taking this into consideration, in 2018, as part of the execution of a fortification workflow of Rocha pears (Pyrus communis L.), a field characterization was carried out before the beginning of foliar spraying, to identify possible limitations to the increase of calcium in fruits. Thus, in March, soil samples were collected from an orchard (i.e., a parcel with 500 m²) located in the West region of Portugal, where this variety is largely produced. During sample analysis, humidity, organic matter, pH, electrical conductivity, colorimetric parameters by CIELab system (with and without organic matter) and mineral analysis by X-ray fluorescence (of soils and fruits at harvest) were assessed. Humidity values indicated an even irrigation on the orchard. Additionally, it was found that organic matter values influenced soil color. Electrical conductivity and pH values were within the recommended range for pomeids. Additionally, higher values of Ca and P prevailed in soils, while K and S contents remained higher in fruits. In conclusion, no major limitations were identified, and field characterization before Ca fortification workflow was useful to assess the orchard`s conditions and possible limitations to nutrient absorption by trees.