Journal of Advanced Laboratory Research in Biology E-ISSN: 0976-7614 Volume 8, Issue 4, 2017 PP 74-78 https:/ / e-journal.sospublication.co.in *Corresponding Author: Dr. Rupa Verma 0000-0001-9363-0623. E-mail: rupavermabiotech@gmail.com Phone No.: Research Article Trichoderma asperellum, a potential fungal biocontrol agent against Aspergillus niger Rupa Verma *1 , Abhijit Dutta 2 , Ashok Kumar Choudhary 1 , and Sudarshan Maurya 3 1 Department of Botany, 2 Department of Zoology, Ranchi University, Ranchi 834001, Jharkhand, India. 3 ICAR–Research Complex for Eastern Region, Research Centre, Plandu, Ranchi 834010, Jharkhand, India. Abstract: Trichoderma asperellum is free-living, ubiquitous fungus which is very common in the habitat of soil and root ecosystem, is known as a potent opportunistic, avirulent plant symbionts and it parasitizes several soilborne phytopathogens. Aspergillus niger is well known black mold which causes several storage diseases. Among the storage diseases, black mould disease of onion is an important disease which is caused by A. niger. Antagonsitic potential of T. asperellum was assayed against three isolates of A. niger [RC1, RC2 (isolated from soil samples of Farm 1 and 2) and RC3 isolated from diseases onion]. Antagonistic efficacy of T. asperellum of A. niger almost similar against all the test isolates. Percentage inhibition of radial growth (PIRG) of A. niger by T. asperellum inhibited 55.17% within five days, 77.20% within 7 days and 92.06% in 12 days. Antagonistic efficacy of T. asperellum can be exploited in the management of black mould disease of onion. Keywords: Trichoderma asperellum, Aspergillus niger, Black mould, Antagonistic potential, Inhibition. 1. Introduction Onion (Allium cepa) is one of the most important vegetable cum condiment crops which belongs to family Alliaceae. In India, Onion is widely cultivated under three cropping seasons, i.e., Kharif, Late Kharif and Rabi. It has valued for their medicinal and therapeutic properties as well as has numerous health benefits likewise treating sun strokes, prevention of cancer and cardiovascular disorders [1]. Besides of several medicinal properties, the onion plants has also affected by insects, pest and diseases during the cropping season as well as in storage too. Among the diseases, a black mould disease on onion is caused by Aspergillus niger is a major postharvest disease-causing pathogen as well as it also reduces the marketable quality [2]. The disease-causing pathogen survives in soil as a saprophyte which infects onion rootlets or neck in the field and finally establishes in bulb of onion [3]. Hayden and Maude [4] reported that 30 to 80% spoilage of onion bulbs during storage is caused by A. niger. Biological control of plant pathogens by microbial bioagents has been considered a more natural and environmentally acceptable alternative to the chemical/synthetic fungicides [5]. Among the beneficial microorganisms, Trichoderma species are highly exploited fungal bioagents throughout the world for the management of soilborne diseases, plant growth promotion and inducing systemic resistance in crop plants to enhancing their resistance level [6]. Several reports indicated that the Trichoderma species have the ability to antagonize a wide range of soilborne phytopathogenic fungi viz., Sclerotium rolfsii, Sclerotinia sclerotiorum, Rhizoctonia solani, Macrophomina phaseolina, Fusarium species [6,7,8,9]. Trichoderma species have competed with soilborne phytopathogens for nutrients and space, direct antagonisms, secreting antibiotics as well as inducing systemic resistance of plants as well as stimulate plant growth promotion by producing of plant growth promoting molecules [10,11]. Several reports indicated that the antagonistic potential of Trichoderma species highly depended on the lytic enzymes, e.g. chitinases and β-1,3-glucanases [12,13]. Occurrence of Trichoderma spp., a very common inhabitant in the organic-rich soil, but their population density drastically reduced due to intensive farming without using organic manures and excessive use of synthetic fertilizer and pesticides in Jharkhand [8].