Integrated Application of Arbuscular Mycorrhizal Fungi and NPK Fertilizer to Enhance Growth and Production of Tomato (Solanum lycopersicum L.)

Abstract

Tomato (Solanum lycopersicum L.) is an important horticultural crop with high economic and nutritional value, yet its cultivation is often sustained by intensive inorganic NPK fertilization that can degrade soil fertility and microbial diversity, motivating integrated nutrient management approaches such as arbuscular mycorrhizal fungi (AMF) inoculation. This study aimed to evaluate the combined effects of AMF and NPK fertilizer on tomato growth and production under greenhouse conditions. The experiment was conducted from April to July 2025 in Makassar, Indonesia, using F1 Servo tomato grown in 40 × 40 cm polybags containing a homogenized medium of topsoil, well-decomposed manure, and rice husk charcoal. A factorial randomized complete block design tested four AMF doses (0, 20, 30, 40 g polybag⁻¹) and four NPK doses (0, 5, 7.5, 10 g polybag⁻¹) with three replicates (16 combinations; 48 units). Data were analyzed by ANOVA, followed by DMRT at α = 0.05. AMF and NPK each significantly increased plant height at 12 weeks after planting, reaching 99.16 cm at 40 g AMF and 97.15 cm at 10 g NPK, with no interaction. Productive branches showed a significant interaction, peaking at 17.56 branches with 30 g AMF + 10 g NPK versus 10.33 in the unfertilized, non-inoculated control. Flowering age also responded synergistically, with 40 g AMF + 10 g NPK accelerating flowering to 39.56 days, whereas delayed flowering (46.56 days) occurred with 30 g AMF without NPK. Fruit number increased independently with AMF (up to 20.42 fruits plant⁻¹) and NPK (up to 20.92 fruits plant⁻¹), and fruit weight per plant rose with AMF (351.24 g at 40 g) and NPK (338.70 g at 10 g), without interaction. Individual fruit weight was not significantly affected, although the highest observed value was 19.54 g at 20 g AMF without NPK. Productivity reached 4.04 t ha⁻¹ with 10 g NPK and increased to 4.84 t ha⁻¹ under 40 g AMF + 10 g NPK, indicating that integrating AMF with NPK can improve key growth, phenology, and yield attributes relevant to more sustainable tomato nutrient management.