Heba I Khan, Suchit A John, Ram Bharose, Reena Kujur
The present investigation evaluated the impact of bio-priming tomato seeds (Solanum lycopersicum L., cv. Pusa Ruby) with Trichoderma harzianum on seedling establishment and the suppression of early-stage diseases under controlled conditions over two consecutive growing seasons (2023-24 and 2024-25). A pot experiment with a randomized complete block design was employed, comprising untreated seeds (T0) as the control and bio-primed seeds (Th), with three replications per treatment. Bio-priming substantially enhanced seed performance, as reflected in improved germination (96.73% in Th vs. 68.42% in T0) and superior seedling morphology. Root length increased from 5.90 to 8.70 cm, shoot length from 8.35 to 10.6 cm, and leaf number from 9.11 to 12.20 in Th. Biomass accumulation was significantly greater, with fresh weight rising from 39.50 to 53.70 mg and dry weight from 3.95 to 5.36 mg, representing a 35.7% increase over T0. These improvements translated into longer seedlings (14.3-19.3 cm) and elevated vigor indices. Moreover, T. harzianum bio-priming reduced disease incidence from 9.63% in T0 to 3.22% in Th, corresponding to a biological control efficacy of 66.6%. Collectively, the findings highlight the dual role of T. harzianum biopriming in promoting seedling vigor and conferring early-stage disease resistance, accentuating its potential in integrated tomato crop management.