Vol. 12, Issue 7 (2023)

The primary disease affecting bael plants is Alternaria leaf spot, which is caused by Alternaria alternata. This disease is increasingly posing a significant challenge in Uttar Pradesh and other regions of the country. In laboratory conditions, the fungus demonstrates robust growth in potato dextrose agar and Bael leaf extract agar mediums. To compare the effects of different solid media on fungal growth, researchers conducted experiments using eight variations. The findings revealed that Potato Dextrose Agar medium exhibited the most substantial mycelium growth, measuring 88.88 mm. Following closely was Beal leaf extract agar medium with 72.00 mm of growth, while Czapeck's Dox agar and Richard's agar mediums showed similar effectiveness with growth measurements of 69.13 mm and 67.60 mm, respectively. Conversely, Martins media displayed the least favorable outcome, supporting a mere 40.15 mm of mycelium growth. These findings highlight that the radial growth of A. alternata depends on the culture media used, with different media influencing the growth rate and pattern of the fungus, resulting in variations in radial growth. The data suggest that, in general, the growth rate increases with time for all media tested, but some media promote faster growth than others. Moreover, sporulation was found to be most favorable in potato dextrose agar and Bael leaf extract agar mediums. Consequently, it can be concluded that potato dextrose agar is the most suitable medium for the growth and sporulation of Alternaria alternata, which causes leaf spot on bael plants (Aegle marmelos Correa).