Vol. 12, Issue 11 (2023)

Author(s):
HB Arpitha, M Mahesh, P Venkataravana, Ambruthavarshini, Dr. Devaraja and YH Preeti

Abstract:
To understand the growth and sporulation of the pathogen, the physiological and cultural characteristics of Colletotrichum lindemuthianum were investigated on six distinct solid media at various pH and temperature levels. The colony growth was significantly superior on Richard’s agar medium with mean colony diameter of 90.00 mm which showed on par with Potato dextrose agar (88.00 mm). Varied degrees of colony colour were observed with brown to white colour having smooth to serrated margin. Among the various degrees of temperature evaluated, with a mean colony diameter of 82.63 mm, it was discovered that 30 °C was the optimal temperature for the pathogen's growth, followed by 25 °C with colony diameter of 71.44 mm. Of the six distinct media, the one with the least amount of fungal growth was observed at 15 °C and the average colony diameter being 6.72 mm. Out of the six tested media Potato dextrose agar and Richard’s agar media were determined to be the most conducive to C. lindemuthianum growth having an average colony diameter of 63.18 mm and 61.34 mm respectively. All the pH levels tested supported growth of the pathogen in different media. The colony diameter of the fungus measured at pH 7 was 78.76 mm, indicating its mean maximum growth. This was succeeded by pH 8 and pH 6, where the colony diameter measured 69.78 mm and 62.27 mm, respectively. Richard's agar and potato dextrose agar were shown to be the most effective among the studied media, with mean colony diameters of 74.01 mm and 75.07 mm, respectively, across all pH regimes.