~ 751 ~ Journal of Pharmacognosy and Phytochemistry 2020; 9(3): 751-753 E-ISSN: 2278-4136 P-ISSN: 2349-8234 www.phytojournal.com JPP 2020; 9(3): 751-753 Received: 18-03-2020 Accepted: 22-04-2020 Diksha Nayak Department of Plant Pathology, College of Agriculture, OUAT, Bhubaneswar, Odisha, India MK Mishra Department of Plant Pathology, College of Agriculture, OUAT, Bhubaneswar, Odisha, India Bipin Pradhan AICRP on fruits, OUAT, Bhubaneswar, Odisha, India Kishan Kumar Sharma Department of Plant Pathology, College of Agriculture, IGKV, Raipur, Chhattisgarh, India Corresponding Author: Diksha Nayak Department of Plant Pathology, College of Agriculture, OUAT, Bhubaneswar, Odisha, India Evaluation of some bio-control agents in in vitro control of Fusarium oxysporum f. sp. cubense, an incitant of banana panama wilt Diksha Nayak, MK Mishra, Bipin Pradhan and Kishan Kumar Sharma Abstract Fusarium wilt of banana popularly known as Panama disease, is a lethal fungal disease caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc) and is one of the most widespread and destructive banana diseases. Present study was taken up to evaluate efficiency of biocontrol agents against banana fusarium wilt to include in integrate disease management strategy as it is eco-friendly technique. The causal organism of panama wilt was tested along with various fungal and bacterial bioagents in dual culture method for testing the efficacy. Results revealed that Trichoderma viride reduced 84.1% radial growth of the causal pathogen followed by Trichoderma harzianum(82.2%) and Trichoderma hamatum(80.1%) while Pseudomonas fluorescens inhibited lowest radial growth (63.08%). Keywords: Panama wilt, bio-control, eco-friendly, Integrated disease management Introduction Bananas are the unsung heroes of the fruit world. Dan Koeppel, author of Banana: The Fate of the Fruit That Changed the World, calls bananas “one of the most intriguing organisms on earth” Fusarium wilt of banana, popularly known as Panama disease, is a lethal fungal disease caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (Foc). (Foc) is recognised as one of the most widespread and destructive banana diseases, and a major production constraint to banana worldwide. Fusarium wilt of banana is a typical vascular wilt disease. The pathogen infects roots of susceptible and resistant banana cultivars, but infection generally progresses into vascular portions of the rhizome only in susceptible genotypes. The pathogen can survive in the soil for several decades by producing spores (specifically, chlamydospores), which will re-infect the susceptible banana plants (Stover, 1962) [12] . This adds to the difficulty of disease management. Biological control has gained great interest in the last years in many pathosystems, including Foc/banana. This has been mainly due to the large input of pesticides, which cause economic, environmental and safety concerns. Biological control must not be a strategy limited to organic farming, but included within integrated disease management frameworks implemented in agricultural systems. Present investigation was taken up to evaluate efficiency of bio control agents against banana fusarium wilt to include in integrate disease management strategy. Martials and Methods Four bio-control agents Trichoderma harzianum, Trichoderma viride, Trichoderma hematum and Pseudomonas fluorescens were tested against Fusarium oxysporum f. sp cubense. Both biocontrol agents and test fungus were cultured on potato dextrose agar in order to get fresh and active growth of each fungus. Twenty ml of sterilized and cooled potato dextrose agar was poured into sterile petriplates and allowed to solidify. For evaluation of fungal biocontrol agent, mycelial discs of test fungus were inoculated at one end of Petriplate and antagonistic fungus was placed opposite to it on the other end at a distance of 5 mm from the periphery. In case of evaluation of bacterial antagonist the bacterium was streaked at ends of the Petriplates and mycelial discs of the fungus was placed at the centre. Four replications were maintained for each treatment. The plates were incubated at 27 ± 1 ºC and zone of inhibition was recorded by measuring the clear distance between the margin of the test fungus and antagonistic organism. The colony diameter of pathogen in control plate was also recorded. The per cent inhibition of the growth of the pathogen was calculated by using the formula suggested by Vincent (1947) [13] .