Fruit Set, Yield, Quality, and Mineral Content Evaluation of 'Pricia' Apricot as Affected by Biostimulants Application

A two-year trial was conducted during 2016 and 2017 seasons in an apricot (Prunus armeniaca L.) commercial orchard located at Cerignola (Foggia province, Puglia region, Southern Italy, 41°15’49’’N; 15°53’59’’E; 126 a.s.l.). The effects of three plant biostimulants (Hendophyt®, Ergostim® and Radicon®, based on biopolymers of polysaccharides, carboxylic acids and humic-fulvic acids, respectively) compared with control treatment, were evaluated on: Flowering, fruit set, yield, total polyphenols content and antioxidant activity, fruits physical-chemical traits and minerals content of the cultivar Pricia. Foliar spray of biostimulants were applied at three phenological stages (calyx perceptible, fruit-set and fruit development) during each growth season. Data showed some specific effects of biostimulants on the quanti-qualitative attributes of fruits. Flowering, fruit-set percentages, and yields were mainly affected by the season, probably because the different chilling hours accumulation during the winter period. Significant interaction between years and biostimulants application were observed. No effect of biostimulant treatments on total polyphenols content and antioxidant activity of fruit were noted in both the years. With regards of the mineral content, only potassium significantly changed.