The effect of nutrient concentration and inoculation of PGPR and AMF on the yield and fruit quality of hydroponic cherry tomatoes (Lycopersicon esculentum Mill. var. cerasiforme)

The purpose of this research was to study the effect of nutrient concentration and inoculation of biological agents (PGPR and AMF) in a hydroponic system of substrate culture on the growth and yield of cherry tomato plants. The greenhouse research was conducted in the Agrotechnopark of the University of Brawijaya at Jatikerto Village, Kromengan Sub-District, Malang Regency. The utilized research method was Completely Randomized Nested Design consisting of two factors. The first factor was the concentration of nutrient solution consisting of 100 % (3.5 dS m-1), 75 % (2.6 dS m-1), and 50 % (1.8 dS m-1) concentrations. The second factor is the inoculation of biological agents consisting of no inoculation of biological agents, PGPR (Plant Growth Promoting Rhizobacteria), AMF (Arbuscular Mycorrhizal Fungi), and PGPR + AMF. The data were analyzed using an analysis of variance and continued with the test of Honest Significant Difference at 5 % level. The results showed that the interaction between the types of biological agents and nutrient concentrations significantly increased the number of flowers, number of fruits, fruit weight, fruit diameter, and sugar content of cherry tomatoes. The AMF application showed the highest fruit weight per plant and fruit diameter, especially at 100 % nutrient concentration. The AMF application also showed a higher sugar content compared to the control and PGPR but not significantly different from the PGPR + AMF treatment at all levels of given nutrient concentration. Fruit weight per plant with treatment of AMF, PGPR + AMF, and PGPR respectively produced 64.47, 48.75 and 29.39 % higher than without application of biological agents.