(1) Official Seed Testing Laboratory, ARO, The Volcani Center, 50250 Bet Dagan, Israel;(2) Dept. of Virology, ARO, The Volcani Center, 50250 Bet Dagan, Israel;(3) Hazera Ltd., 79836 Brurim, M.P. Shikmim, Israel
Abstract:
An indexing system for detectingTomato mosaic virus (ToMV) in commercial tomato seed lots is described. Factors associated with the procedure were analyzed and the following standard two-step working scheme is proposed: (i) mass screening by ELISA for the presence of the virus; (ii) evaluation of virus infectivity within the infested seed lots. A threshold of 10 ng ml−1 was determined for detection of purified ToMV by either ELISA or plant inoculation.Nicotiana tabacum cv. Xanthi NN was found to be a highly sensitive local lesion assay plant for the detection of ToMV. A positive ELISA threshold (1.3 times above the non-specific background) was set for seed samples taken from commercial seed lots by testing the same samples by both ELISA and a bioassay. http://www.phytoparasitica.org posting July 14, 2004.
