Growing use of chemicals under high value vegetable crops tomato for pest and disease management is one of the prime concerns of food safety. Scientific identification and deployment biocontrol agents are a promising alternative management strategy for sustainable pest and disease management. In this context, characterization native microbial strains will be an important step towards successful biocontrol programme. Five indigenous Fluorescent Pseudomonads (FLPs) were isolated from the rhizosphere of various crops, viz., Rice, Okra, Barley, Brinjal and Chickpea from different locations of Bihar. In-vivo and in-vitro studies were conducted on five isolates namely FLP; Rice, Okra, Barley, Brinjal New, and Chickpea, against Fusarium oxysporum f.sp. lycopersici (FOL) and Alternaria alternata, Alternaria solani, causing wilt, brown spot and early blight respectively. Maximum percent of inhibition in the growth of fungi in dual culture was recorded by FLP Brinjal New (37.64%), FLP Rice (41.78%), and FLP Brinjal New and FLP Barley (37.64%), respectively. Seed bacterization with FLPs using a talc based FLP formulation increased germination percentage, days to 50 per cent germination, and seedling vigour. In the paper towel method of germination testing, FLP Brinjal New bacterized seeds took the least number of days (4 days) to 50 per cent seed germination and maximum germination percent was observed under FLP rice (96.33%). When bacterized seeds were planted in portrays, maximum germination was shown by FLP Brinjal New (95.33) while the least germination was recorded under untreated control and FLP rice (89.33). Maximum shoot length, root length, and seedling length were for bacterized seedlings of FLP Rice, FLP barley, and FLP Rice respectively. Two tomato pathogens, Alternaria solani causing early blight and Fusarium oxysporum f.sp. lycopersici causing wilt, were inoculated on the seedlings of FLP bacterized tomato. The minimum disease index against Alternaria solani was found under FLP Barley (17.96%) and against F. oxysporum f.sp. lycopersici, FLP Rice (44.71%) performed better than the other isolates. Among the seedling challenged with FOL, the earliest seed germination and maximum germination percentage were observed under seed bacterized with FLP Barley. Shoot length, root length, seedling length, and seedling vigor were maximum for FLP Rice bacterized seedlings.

Biocontrol, Florescent Pseudomonad, Fusarium wilt, Seed bacterization, Tomato

The research highlights the potential of native Fluorescent Pseudomonads (FLPs) isolated from diverse crops in Bihar for effective biocontrol of tomato pathogens, Fusarium oxysporum f. sp. lycopersici and Alternaria spp. The study demonstrates the positive impact of FLP seed bacterization on germination, seedling vigor, and disease resistance. These findings underscore the significance of harnessing native microbial strains as a sustainable and promising strategy for managing pests and diseases in high-value vegetable crops like tomato, contributing to improved food safety and agricultural sustainability.

Munni Kumari, Zaya Roshani, Srinivasaraghavan A., Ramesh Nath Gupta, Kalmesh Managanvi and Erayya (2023). In-vitro and In-vivo Biocontrol potential of Florescent Pseudomonads against Major Diseases of Tomato. Biological Forum – An International Journal, 15(8a): 307-311.