Cultural and morphological variabilities of Tilletia indica, causal agent of Karnal bunt of Wheat

Variation in morphology and cultural characteristics among 10 representative Indian geographical isolates of Tilletia indica, the causal agent of Karnal bunt of Wheat was studied. All the isolates showed high level of variability in vitro in respect of radial growth maximum observed at 18°C (27.9mm) and secondary sporidia at same temperature 54.28x 10⁴/ml, mycelia dry weight at pH 6 maximum (150.86 mg) and secondary spordia produced maximum (34.9) at pH 5, size of the teliospore (38.4 μm) of KB 31 collected from Yamuna Nagar (Haryana), germination percentage was maximum (32.1%) and number of primary sporidia maximum (110.6 μm) at 18°C of KB 1 isolates of Kotputaly (Rajasthan). Substantial variation was found in radial growth, secondary sporidia production, mycelia dry weight among these isolates in different temperatures and pH in PDA medium.