Abstract

COMPARISON OF CULTURAL AND MORPHOLOGICAL VARIATION AMONG DIFFERENT FUSARIUM OXYSPORUM ISOLATES CAUSING ROOT ROT OF SOYBEAN (GLYCINE MAX)

Jamadar A. M. and Khade S. K.*

Abstract

18 isolates of Fusarium oxysporum causing root rot of soybean were recorded for its cultural and morphological variations. The Fusarium oxysporum isolates Fo4, Fo8, Fo 11, Fo12, Fo14, Fo15, Fo16, Fo17, having the radial colony growth between diameter of 85 mm to 90 mm were among the fast growing category whereas isolates Fo1, Fo3, Fo10, Fo13, Fo18 showed colony growth between 66 mm to 80 mm classified as medium growing and bellow 64 mm growth of isolates were recorded as slow growing. The biggest size macro-conidia were obtained in isolates Fo 18 (30 – 32 × 5 – 6 μm) whereas, the smallest size were obtained from isolate Fo6 (11 – 13 × 3 – 4 μm). The biggest size micro-conidia were obtained in isolate Fo18 (7 – 10 × 1 – 3 μm) whereas, the smallest size were obtained from isolates Fo5 and Fo6 (2 – 4 × 1 – 2 μm). The number of septa in macro and micro-conidia were3-4 and 0-1 respectively all conidia showed hyline nature. The Macro-conidia were sickle shaped with blunt ends and micro-conidia were round to oval. Chlamydospores were recorded from all 11 days culture of F. oxysporum. The highest dry mycelium weight was obtained from the isolate Fo13 having weight 188.0 mg and minimum dry mycelium weight 133.0 mg was obtained from the isolate Fo8.

Keywords: Root rot, Soybean, Variation, Conidia, Fusarium oxysporum.