Influence of soil properties on yield and fruit maturity at harvest of ‘Williams’ pear

In the Upper Rio Negro Valley, northern Patagonia, there is a large variability of soils and the success of a fruit plantation depends mostly on soil characteristics. The main objective of this work was to determine the relationships between yield and fruit internal maturity at harvest of pear trees grown in soils with different properties. The soil around each of 30 trees was morphologically characterized by measuring physical, physic-chemical, and chemical variables. At harvest time, total and commercial yields were measured, and maturity was determined by measuring flesh firmness, soluble solids, and titratable acidity. According to edaphic variables, soils were classified into five groups. Yields presented significant differences among such groups and growing seasons. The distribution of commercial sizes was similar in soils with fine texture, and high K content and cation-exchange capacity. Smaller fruits predominated in soil groups with high salinity and shallow depth. The soil group with the highest salinity presented fruits with 11% more titratable acidity compared to all other groups.