Physiological studies of Helminthosporium Pathovars Isolated from Infected Maize Plant in the Region of Karnataka

Karnataka is one of the potential maize producing regions in India. Therefore maize in this region has the potential to become diseased under certain conditions. Diseases of crops can affect plant physiological activities, yield and/ or quality of the harvested commodity which can impact profitability and increase the risks of farming. Disease management is one of the major problems faced by farmers, and this has become a big threat and made farmers to become risk adverse to invest in farming as a business. This study is about to determine suitable culture conditions such as different culture media, optimum temperature, pH, carbon source were optimized to culture Helminthosporium in laboratory conditions to do characterize the gene for pathogenicity. Among all the media the best media were found to be the MRBA and PDA. It was found to be the optimum temperature and pH were20o& 25o and pH of 5& 6. Carbon source for the optimum growth was selected by growing in different carbon sources. It was revealed that best carbon source found to be starch for better growth of colonies. Along with these parameters, toxin study of the Pathogen was done. The crude phytotoxic was extracted from culture filtrate using methanol and chloroform. TLC revealed the presences of toxin in crude extract.