Effects of foliar fertilization of biostimulants obtained from sewage sludge on olive yield

The objective of this study was to investigate the effect foliar fertilization two biostimulants (BS1 and BS2) obtained from sewage sludge by fermentative processes using Bacillus licheniformis during four consecutive seasons in an olive tree crop applied at a dose 6 L ha-1 divided into three applications (before flowering, beginning flowering fruit set). BS2 had higher number low molecular weight peptides BS1. contents macro micronutrients leaves, photosynthetic pigments yield were plants fertilized with than With respect control treatment for 2017 2019 seasons, increased 20–22% 28–29% For 2018 2020 35–36% BS1 42–43% BS2. These results suggest that use these biostimulants, contain peptides, could be great interest farmers as regards improving yield.