Biological control of crown rot of groundnut by Trichoderma harzianum and T. viride uri icon

abstract

  • Crown rot of groundnut (Arachis hypogaea) caused by Aspergillus niger is prevalent in warm and dry climatic zones and its incidence ranges from 2% to 14% (Pande and Narayana Rao 2000). The pathogen attacks groundnut plants at all the growth stages and causes pre-emergence rotting in seeds, soft rot in emerging seedlings, and crown rot in mature plants. Thus, management ofcrown rot by fungicides is difficult and expensive. Biological control of plant diseases is cost effective and environmentally safe compared to fungicides. Also, the biocontrol agent once established persists in the soil for longer periods and offers disease protection even in the consecutive crop seasons (Mew and Rosales 1986). Trichoderma spp are antagonistic to a wide range of phytopathogenic fungi and are able to control economically important diseases in several crop plants (Papavizas 1985). Trichoderma harzianum and Bacillus subtilis AF 1 were tested to control the incidence ofcrown rot in groundnut and varying levels of disease control were obtained with these biocontrol agents (Lashin et al. 1989, Podile 2000). Bacillus subtilis AF 1 induced production of lipoxygenase and altered the phytoalexin metabolism in groundnut seedlings (Podile 2000). We report the results of the in vitro antagonistic potential of 16 Trichoderma isolates against A. niger and the efficacy of the selected isolates to control A. niger infection under greenhouse conditions in comparison with a fungicide

publication date

  • 2001