A RAPID SENSITIVE AND RELIABLE METHOD FOR DETECTING RALSTONIA SOLANACEARUM USING FTA WHATMAN CARD
K.N. Chandrashekara, M.K. Prasannakumar, M. Deepa, A. Vani
DNA isolation for the molecular characterization of Ralstonia solanacearum using conventional methods takes 2 to 3 days. The use of FTA (Whatman) card reduces the time for obtaining nucleic acid and large samples can be stored on these cards for several years. This paper presents a comparison of the use of genomic DNA obtained from FTA card with a conventional method. The FTA card method proved to be an efficient way of sampling and detecting R. solanacearum as it eliminates the need for multi-step extraction and purification procedures which often involve the use hazardous chemicals and require refrigeration. In this study bacterial ooze from infected plants of tomato, potato, pepper and eggplant was directly collected on this card and air-dried for 5 min. A small fragment of the card (<1 mm) was subjected to PCR with universal primers and the results were compared with those yielded by a conventional method. PCR products obtained with the FTA method were sufficient for reliable scoring and were comparable to genomic DNA isolation by conventional method. Our findings indicate FTA card technique as an appropriate method for the fast and reliable diagnosis of R. solanacearum.