Y. VANI*, R. SARADA JAYALAKSHMI, P. MADHUSUDHAN and V. LAKSHMI NARAYANA REDDY Department of plant pathology, S. V. Agricultural College, ANGRAU, Tirupati – 517 502, Chittoor Dt., A.P., India

ABSTRACT

Twelve isolates of Sclerotium oryzae (Catt). causing stem rot of rice were collected from major rice growing areas in Andhra Pradesh, India. Variability among these isolates of S. oryzae was assessed based on utilizing various carbon sources using three different growth media and growth rate on PDA. Among the different media tested, PDA was well supported for growth of all isolates and there was sparse growth on OMA and very sparse growth on CZA of all the isolates of S. oryzae. was noticed. Depending on the growth rate on PDA medium, isolates of S. oryzae categorised into four groups very fast growing, fast growing, medium growing and slow growing. Mostly reddish brown, dark brown and light brown sclerotia were observed in the isolates.Hence this study clearly indicated the cultural and morphological variability among Sclerotium oryzae isolates

KEYWORDS :

Growth media, morphology, mycelium, sclerotia