Studies on Fungal Pathogens of Terrestrial Weeds of Kurukshetra

During extensive surveys conducted to search for naturally occurring fungal pathogens on various terrestrial weeds of Kurukshetra and its adjoining areas, dominance of Deuteromycetous fungi followed by obligate fungal pathogens were noticed. A total of 12 fungal pathogens were identified on 10 weeds belonging to 9 different families of Angiosperms on the basis of their morphological characteristics. Typical disease symptoms were produced by all non obligate pathogens on their respective hosts in vitro. Inoculated pathogens were isolated and were found similar to original isolates in cultural characteristics thus confirming the pathogenicity to their respective hosts and competing Koch's postulates. Leaf spots, powdery mildews, downy mildews, rust, and smut were the main diseases caused by the fungal pathogens on various terrestrial weeds of Kurukshetra. Symptoms of diseases caused by these pathogens and cultural characteristics of 12 fungal pathogens were recorded. Alternaria cassiae on Cassia occidentalis, Cercospora sp.-I on Ageratum conyzoides, Cercospora sp.-II on Alhagi camelorum, Cercospora sp.-III on Alternanthera pungens, Cercospora sp.-IV on Argemone mexicana, Cercosporsa sp.-XI on Peristrophe bicalyculata, Peronospora arborescens on Argemone mexicana, Puccinia sp. on Rumex dentatus, Ustilago cynodontis on Cynodan dactylon, Oidium sp.-I on Ageratum conyzoides, Oidium sp-IV on Sida rhombifolia and Peronospora sp. on Chenopodium album are new reports of occurrence of these pathogens from this region.