Transgenic tobacco plants show different resistance to Rhizoctonia solani AG 4 and AG 8

Transgenic tobacco plants expressing chitinase, ribosome-inhibiting protein or glucanase transgenes from barley, either singly or in combination, were tested for resistance to Rhizoctonia solani Kühn AG 4 and AG 8. With two exceptions out of 12 tests, the transgenic plants were resistant to AG 4 isolates, whereas only those plants showing high level expression of chitinase genes were resistant to AG 8 isolates. The level of resistance was markedly affected by the medium used to germinate the seeds and by the isolate used