Differential invasion by tobamoviruses of Nicotiana megalosiphon following the hypersensitive response

The tobamoviruses tobacco mild green mosaic virus (TMGMV) and tobacco mosaic virus (TMV) differ in their behavior in Nicotiana megalosiphon. Both viruses induce necrotic lesion formation in the inoculated leaves, but only TMV moves from the initially infected (necrotic) areas and is able to spread systemically, overcoming the hypersensitive response. The appearance and growth of necrotic local lesions induced by TMV or TMGMV in N. megalosiphon were shown to follow similar kinetics; however, virus accumulation in the local lesions was about five times greater for TMV than for TMGMV. In accordance with this, TMV replicated to much higher levels than TMGMV did in N. megalosiphon protoplasts [...]