Studies on various histopathological parameters to evaluate the biological control potential of Alternaria macrospora MKP1 against Parthenium weed

Parthenium hysterophorus (Asteraceae) is known as one of the most troublesome weeds, causing severe environmental, economic, human and animal health problems in India and around the world. During a series of surveys for natural enemies of P. hysterophorus, a leaf blight pathogen was isolated from the affected parts of the Parthenium following the standard isolation techniques using potato dextrose agar (PDA) media. Koch’s postulates were performed and found satisfactory for the isolate and proved to be pathogenic to this weed. On the basis of cultural, morphological and molecular characteristics, the pathogen was identified as Alternaria macrospora MKP1. The pathogen was studied for various histopathological parameters and the results showed that this pathogen has a good potential to control Parthenium weed.