Integrating Bio-enzyme with Fertilizer: Comparative Effects of Foliar and Soil Application on Early Growth, Leaf Pigments and Stress Mitigation in Tomato Plants

Bio-enzyme, a liquid prepared by fermenting fruit-based organic materials, has potential as a sustainable supplement to conventional fertiliser. Its effectiveness may vary with application mode and concentration. The study evaluated the effects of fertiliser-integrated foliar and soil applications of bio-enzyme on early-stage growth and biochemical parameters in tomato (Solanum lycopersicum) plants. Bio-enzyme treatments were applied at three concentrations through foliar and soil application, each in combination with fertiliser, and responses were assessed after 15 days of the first and second applications. After the first treatment, BF2F (2 mL L⁻¹, foliar + fertiliser) was superior for branch development and significantly enhanced chlorophyll a, chlorophyll b, and carotenoid contents. BS3F (15 mL L⁻¹, soil + fertiliser) also significantly enhanced chlorophyll b and carotenoid levels. BF1F (1 mL L⁻¹, foliar + fertiliser) significantly enhanced plant height and leaf production, while the most pronounced response occurred with the soil application of BS3F, after the second treatment. Oxidative-stress indicators were reduced in BF2F while peroxidase activity was enhanced in BF3F (3 mL L⁻¹, foliar + fertiliser) and BS1F (5 mL L⁻¹, soil + fertiliser). One-way ANOVA also showed significant differences among the different fertiliser-integrated foliar and soil treatments according to concentration. These findings support the use of bio-enzyme as a complementary input with fertiliser, facilitating the gradual adoption of bio-based crop management or reducing sole dependence on chemical fertilisers.