Author(s):

Rajappa Vithal, Mina D Koche, Aparna Tekade and BT Raut

Abstract: Ten isolates of Colletotrichum capsici collected from different regions of Vidarbha, Marathwada (Maharashtra), Bidar district (Karnataka) and Guntur district (Andhra Pradesh) showing varied type of pathogenic ability against chilli variety Jayanti and designated as strongly, moderately and weakly pathogenic on the basis of per cent disease intensity. Morphological characters of ten different isolates with respect to radial mycelial growth, conidial characters, setae and acervuli were studied on PDA to know the variability among the isolates. Isolate Cc₁, Cc₆ and Cc₇ exhibited similar colony colour, conidia and acervuli characters, Cc₂ and Cc₄ forming ash colonies with concentric rings, while Cc₃, Cc₈ and Cc₉ showed white to ash colonies and Cc₅ and Cc₁₀ form light black colonies. Conidia of all the isolates were sickle shaped having oil globule at the centre but setae were longer than conidial mass in all the isolates. Among the ten isolates of C. capsici, maximum radial mycelial growth of 82.42 and 81.94 mm was recorded in Cc₅ and Cc₇ respectively, whereas minimum growth (74.28 mm) was recorded in Cc₃ at 7 DAI. Micrometrical observations with respect to conidia, acervuli and setae revealed the differences. The dimension of conidia i.e. length and breadth among ten isolates ranges from 18.64 – 30.31 x 2.75 – 8.20 µm, whereas acervuli length was 295.96 µm and breadth 292.16 µm in Cc₁₀. Maximum conidia length i.e. 30.31 µm and breadth 8.20 µm was observed in Cc₄ and maximum length of setae (212.98 µm) in Cc₇.

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