Vol. 11, Issue 10 (2022)

Author(s):
Udhayakumar M, Narola Pongener and Hijam Meronbala Devi

Abstract:
A field investigation was conducted in Coimbatore district of Tamil Nadu in the year 2020 to 2021 in order to identify the fungal plant diseases of some important crops (rice, maize, black gram, groundnut and cotton). The diseases were identified based on the development of characteristic disease symptoms on the plant and morphological studies of the associated micro-organism under the microscope and were identified as Blast of Rice (Pyricularia oryzae), Sheath blight of Rice (Rhizoctonia solani), Sheath rot of Rice (Sarocladium oryzae), False smut of Rice (Ustilaginoidea virens), Southern leaf blight of Maize (Bipolaris maydis), Powdery mildew of Blackgram (Erysiphe polygoni), Early Tikka leaf spot of Groundnut (Cercospora arachidicola) and Alternaria leaf spot of Cotton (Alternaria alternata). The per cent disease incidence was assessed by recording the number of plants showing disease symptoms and the number of plants examined, where highest incidence of all the fungal diseases was recorded in Pollachi (North). It was also observed that Pollachi (North) block had the highest PDI (Per cent Disease Index) values for all diseases when compared to Udumalaipettai block.