Abstract
This study investigates the molecular mechanisms by which Hariman mitigates damage and productivity losses caused by Cucumber Aphid-Borne Mosaic Virus (CABMV) in the passion fruit genotypes 'FB300' and 'H09-110/111' under greenhouse and field conditions in Rio de Janeiro, Brazil. Hariman treatment induced the upregulation of key defense genes and phytohormones in response to CABMV infection, enabling treated plants to counteract virus-induced developmental impairments effectively. The relative accumulation of CABMV and disease severity were significantly reduced, with treated plants showing no decline in growth parameters such as height, leaf count, flower production, or fruit set. Over 18 months, total productivity increased by 65.7% and 114% for 'FB300' and by 44% and 80% for 'H09-110/111' after one and two applications of Hariman, respectively. Notably, infected plants treated with Hariman outperformed healthy plants grown under similar conditions, underscoring the biofertilizer's dual role in promoting plant growth while enhancing resistance to biotic stressors. These findings indicate that Hariman stimulates robust growth and induces the expression of the defense-related genes PR-3, SOD, POD12, PAL, and LOX2 alongside the expression of the phytohormone-associated genes SAUR20 and GA2ox across different passion fruit genotypes. The adoption of these sustainable technologies holds significant potential for enhancing passion fruit productivity in the face of diseases that severely threaten this crop.