Abstract
This study investigated the effects of fungal (Penicillium chrysogenum, Thielavia basicola, Curvularia hawaiiensis) and bacterial (Sphingomonas aquatilis, Bacillus licheniformis, Exiguobacterium aurantiacum, Micromonospora echinaurantiaca, Kocuria rhizophila) endophytes on the growth and physiological traits of tomato plants (Solanum lycopersicum L.) under greenhouse conditions. Both individual and combined endophyte treatments significantly enhanced key growth parameters, including stem weight, height, and dry weight, with notable synergies observed in fungal-bacterial combinations such as P. chrysogenum + E. aurantiacum and S. aquatilis + M. echinaurantiaca. These combinations also optimised photosynthetic activity, increasing chlorophyll content, carotenoids, and photosystem II efficiency, improving plant vitality. Additionally, these endophytes stimulated a marked increase in carotenoid levels, with fungal-bacterial combinations leading to substantial improvements in antioxidant activity. Furthermore, inoculation with these endophytes promoted higher phenolic and proline content, with distinct combinations showing remarkable effects on carbohydrate accumulation. The findings underscore the synergistic potential of fungal-bacterial endophyte interactions in enhancing plant resilience, offering promising strategies for improving crop productivity and sustainability in agriculture.