TRIBAS is a biopesticide formulation developed from bacterial consortia of B. subtilis isolates. The formulation can control maize diseases, particularly those caused by pathogenic fungi. This research was conducted to validate the effectiveness of TRIBAS to support growth and yield of several maize inbred grown for parental seed production of several high yielding hybrids. A local seed growers’ participatory evaluation was set up in three districts in South Sulawesi (Maros, Soppeng, and Bone) using 5 maize inbred, i.e., MR-15, N-79, NEI-9008, AMB-20, and MAL-03. Each was grown following standard seed growing procedures with an additional treatment, with and without TRIBAS application. The results showed that the application of TRIBAS through seed treatment and plant spraying was able to inhibit the incidence of three main fungal diseases in maize, i.e, P. philippinensis, R. solani and B. maydis. The application did not result in significant seed productivity increase; however, it provides economic added value of up to IDR 5,724,000/Ha, considering that the seeds being propagated are parental seeds whose prices are relatively high (Rp 90,000/Kg). Continuous application of TRIBAS is expected to increase bacteria population in the soil, which, gradually would result in the increase of crop productivity.