Enzyme activity in banana fruits rotted by Botryodiplodia theobromae Pat.

Abstract

Peroxidase and polyphenol oxidase activities in fruits of two cultivars of banana, 'champa' and 'kanthali' rotted by <i>Botryodiplodia theobromae</i> Pat. was studied. The enzymes showed much higher activities in infected than that in uninfected 'tissues. Increase in peroxidase activity was evidently inhibited by cycloheximide. Polyphenol oxidase activity was also inhibited in presence of phenylthiourea and Na-diethyldithiocarbamate more strongly by the former. Increase in activities seemed to be due to increased sytheses of the enzymes. In an <i>in vitro</i> culture, the fungus exhibited some peroxidase but no polyphenoloxidase activity.

Role of Total Soluble Sugar, Phenols and Defense Related Enzymes in Relation to Banana Fruit Rot by Lasiodiplodia theobromae [(Path.) Griff. and Maubl.] During Ripening

“…Our results suggests that PPO activity was increased beginning the fruit ripening and further increased with the increasing storage time but increment was more pronounced in the inoculated fruits. These results are consistant with earlier workers they also observed increased polyphenol oxidase in banana fruit infected by Botryodiplodia theobromae [24]. Polyphenol oxidase and peroxidase activity gradually decreased during the development of the fruits followed then by an increase during the ripening period.…”

“…These results suggest that the peroxidase genes may be inducible during the pathogenesis of the anthrachose disease rather than in the disease resistance response. Similar results were observed in banana fruit infected by Botryodiplodia theobromae [24]. Change in peroxidase levels in mango fruits at various stages of ripening.…”