Influence of Foliar Application of Aqueous Garlic Extract on Growth, Yield and Nutritional Quality of Four Varieties of Tomato (Solanum lycopersicum L.)

Abstract

Botanical extracts have recently gained attention as bio-stimulants in vegetable production. This study examines the influence of aqueous garlic bulb extract (AGE) on the growth, nutritional composition, and antioxidant enzyme activity of four tomato varieties grown in a screen house. The experiment followed a 3 x 4 × 4 factorial layouts in a completely randomized design (CRD) with three replications. The treatment includes four tomato varieties (Premium, Royal Bold, Sayo and Akungba Local) and four different frequencies of AGE foliar spray: 0 (Control), F1 (once), F2 (twice), and F3 (three times), applied at transplanting, flowering, and fruiting stages. Data were collected on plant height, leaf area, stem girth, number of branches, green leaves at transplanting, 50% flowering and maturity, plant biomass, fruit weight, and total number of fruits per plant. The treatments positively (p < 0.05) influenced some growth parameters of AGE-treated tomato plants, such as plant height, leaf area, number of branches, and senescence leaves at 50% flowering and fruiting stages. A positive effect of AGE applied twice (F2) was observed, particularly in the Premium variety, which consistently showed greater height, increased leaf area, and more senescence leaves. Additionally, thrice foliar application (F3) across all varieties led to enhanced antioxidant enzyme activity (superoxide dismutase, SOD) and chlorophyll content at the fruit-setting stage. These findings suggests that AGE can serve as an effective bio-stimulant to improve tomato growth under screen house conditions.