Coat protein sequence of Krish-infecting strain of Johnsongrass mosaic potyvirus.

The morphology of an Australian strain of Johnsongrass mosaic potyvirus (JGMV Krish-infecting strain), capable of infecting sorghums carrying the Krish potyvirus resistance gene, was investigated and the base sequence of the coat protein region determined. Under the electron microscope the virus was indistinguishable from the wild type prevalent in Australia, JGMV-Jg. However, there were some significant changes in the inferred amino acid sequence in both the N-terminus and the core regions of the coat protein. Some of these amino acid changes may be responsible for breaking the resistance of sorghums carrying the Krish virus resistance gene. In the discussion mention is made of a preliminary result with a mutated in vitro transcript which supports this suggestion.