Impact of Seaweed Extract and Trichoderma Fungus on Some Traits of Lettuce

Abstract

The study was conducted in the Horticulture Department field located in the Tourist Forest area during the 2024–2025 growing season. It involved three factors: Factor 1: Seaweed Extract (Stimax Nature) Applied in three concentrations: 0 ml L⁻¹ (control), 5 ml L⁻¹ and 10 ml L⁻¹ Factor 2: Trichoderma Fungus (Trichoderma asperellum) Applied at three levels: No fungus (control), 1 g plant⁻¹ and 2 g plant⁻¹. The fungus was added to the planting hole 10 days before transplanting. Seedlings were then transplanted with the fungus placed beneath the root system of each plant. Factor 3: Lettuce Cultivars>This factor included two imported lettuce cultivars: ‘Nader’ and ‘Fajr’. The experiment included 18 treatments (3 × 3 × 2) in three replicates and was conducted as a field factorial experiment using a Randomized Complete Block Design (RCBD). Treatments were randomly distributed according to the experimental design. The data were statistically analyzed, and treatment means were compared using Duncan’s Multiple Range Test at a significance level of ≤ 0.05. The study demonstrates that seaweed extract and Trichoderma fungus can positively influence important lettuce traits, providing a viable pathway for eco-friendly horticultural enhancement, improved productivity, and more sustainable agricultural practices.