Phenylalanine Controls Blackberry Growth in Sustainable Soilless Culture and Enhances the Content of Phenolic Compounds

Abstract

Abstract The study was conducted at Research Station A in the Coll. of Agri.Engi. Sci., U. of Baghdad during the 2022-2023, aiming to improve the vegetative growth and phenolic concentration in blackberry leaves by growing the plants in organic substrate soilless culture systems including licorice root residues (C3) and cocopeat (C2) compared to field soil (C1), as well as spraying the plants with phenylalanine (A) at three concentrations (0, 100, 200 mg.L-1). The results showed the superiority of the plants growen in cocopeat sprayed with 200 mg.L-1 of phenylalanine (C2A2) exhibiting the highest N%, P%, plant height, leaves number, total leaf area, increase in protein%, chlorophyll, and total flavonoids in the leaves, while(C3A2) was superior, in leaves beta-carotene and total phenols.