Summary: Recent strategies have focused on enhancing the sustainability of horticultural crop production systems, with biostimulants emerging as a promising tool. Among these, protein hydrolysates (PHs)—mixtures of peptides and amino acids—have gained attention for their positive effects on crop performance. Produced through enzymatic or chemical hydrolysis of animal- or plant-derived proteins, PHs improve crop quality, nutrient efficiency, and stress tolerance. This review explores the properties of PHs as plant biostimulants, covering their classification, chemical composition, and the effects on plant metabolism and stress tolerance. It concludes with suggestions for future research to better understand PHs’ modes of action and optimize their application.
Publication: Scientia Horticulturae
