Impact of Organic Fertilization on Morpho-Chemical Traits and Bioactive Compounds in Young Opuntia Ficus-Indica Hybrids

Organic amendments can enhance the early establishment of Opuntia ficus-indica under semi-arid conditions. This study evaluated the effects of two low-cost compost-based fertilization strategies: solid compost (10% v/v in planting pits) and compost tea (10% w/v fermented 48 h; applied monthly at 15% of pit capacity) on morphology, chemistry, and some bioactive of three prickly pear hybrids (red, white, honey) grown at the College of Agriculture, Tikrit University (April–October 2024) on a sandy loam soil. A strip–split RCBD with four replicates compared nine (hybrid × amendment combinations). Traits included plant height, cladode number and area, root traits, dry matter, ash, Nitrogen and crude protein, total chlorophyll, flavonoids, and proline. Relative to the unamended control, solid compost increased vegetative stature (e.g., plant height up to ~18% and cladodes per plant by ~56% in the red hybrid), while compost tea most strongly improved physiological quality (total chlorophyll to 1.157 mg g⁻¹ and N to 1.78%, equivalent to 11.12% crude protein). Ash content rose to ~24–25% with either amendment. Flavonoids remained high (≈26.6–29.0 mg 100 g⁻¹), with genotype-specific responses, whereas proline declined from control levels (~360–373 mg 100 g⁻¹), indicating reduced stress. Many effects and hybrid × amendment interactions were significant (ANOVA; LSD, p ≤ 0.05). We conclude that solid compost is preferable when structural growth is prioritized, whereas compost tea better enhances leaf biochemistry; hybrid choice further modulates.