METICULOUS ISOLATION AND PURIFICATION OF CAUSATIVE AGENT: A DECISIVE STEP IN THE STUDY OF BACTERIAL BLIGHT DISEASE (BBD) OF POMEGRANATEM.M. Bendigeri1, Y.C. Attar and G.R. PathadeAbstract Xanthomonas axonopodis PV punicae [Xap] is the causative agent of bacterial blight disease of pomegranate. The disease is severe and can cause upto 80 to 90% reduction in the yield of pomegranate. A variety of approaches have been tried for the control of the disease. The first step in such study is isolation of bacterial blight pathogen Xap from infected pomegranate fruits or leaves and further maintenance of pure culture. Xap develops colourless to faint yellow, highly mucoid colonies on Nutrient Glucose Agar [NGA] medium. Many researchers get confused at this step with the colonies of Xap. In current research work also, correct isolation method of the pathogen was performed. Here, the suspected Xap pathogen was isolated from the infected plant parts by standard isolation procedure. The suspected pathogen was then streaked on NGA plate. The plate was incubated at 28 0C for 72 hr. After incubation, the critical point of study was the selection of Xap colonies. These colonies were selected as suspected Xap isolates. These isolates were purified by repeated subculturing and then preserved on sterile NGA slants. The confirmation of isolate as Xap, causative agent of Bacterial Blight Disease of pomegranate was done by applying Kochâs postulates on healthy plants. |