Abstract

                                Dry root-rol' or 'Root-rol' caused by Rhizoctonia batati- cola (Taub.) Butl., is one of the most important diseases affecting groundnut. It is reported from Argentina that the disease caused by this pathogen is responsible for upto 70 per cent loss of the crop in humid season or in low lying areas (Macola, 1950). Infection occurs at almost any stage of develop- ment from seedling to maturity (Purss, 1962). However, infection at the pre-emergence stage is much more severe than at the post-emergence stage. It is generally found that the bunch varieties are more prone to the attack by this pathogen than the semi-spreading and spreading varieties. It has been reported by many workers that this disease can be checked to a considerable extent and pod yield increased by pre-treatment of the seeds with suitable fungicides. In recent times many fungicides have been formu- lated exclusively for seed treatment and marketted. It was with the object of selecting the best suited fungicides capable of controlling groundnut seed- borne pathogens, field studies were conducted with ten selected fungicides at the Regional Agricultural Research Station, Tindivanam, Tamil Nadu during the three years 1966 to '68 and the results obtained are presented in this paper.

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