Abstract– For the research of Koch’s postulate, a survey and collection of commercially available fruits with disease symptoms was conducted. Fruits with disease signs that are being sold in the city’s various markets were gathered and inspected. One of the world’s biggest issues with countries that grow fruits and vegetables is fruit loss after harvest. There are reports of losses of millions of rupees annually due to post-
harvest disease caused by different types of mycoflora during transportation and storage periods. The aim of the study is to select diseased fruits and observed the pathogen which is responsible for causing diseases and these pathogens were inoculated and transferred to sterilized fruits for confirmation of pathogen as per Koch’s postulates. Banana, Star fruit, Amla, orange, and pineapple are significant fruits with nutritional
qualities that were chosen for the present study. Both in storage and on the market, several micro fungi have affected these significant fruits. These significant fruits are deteriorating as a result of the micro fungi infestation, making them unhealthy and unfit for human consumption. The pathogenicity was tested
according to Koch’s postulates. There was variation in the mycoflora according to the type of fruits. According to the present findings, all of the fruits in this study showed positive result against Koch’s postulates. Aspergillus sp, Mucor sp, were isolated as the dominant fungi in all the affected fruits