Question

which pathogen was the first virus ever discovered, identified by dmitri ivanovsky in 1892? fire blight late blight tobacco mosaic virus fusarium wilt

Explanation:

Dmitri Ivanovsky, a Russian botanist, conducted experiments on tobacco plants in 1892. He found that the sap from diseased tobacco plants, even after filtering through a Chamberland filter (which retained bacteria), could still infect healthy tobacco plants. This led to the identification of the Tobacco Mosaic Virus as the first - discovered virus. Fire blight is caused by the bacterium Erwinia amylovora. Late blight is mainly caused by the oomycete Phytophthora infestans. Fusarium wilt is caused by fungi in the Fusarium genus.

Answer:

Tobacco Mosaic Virus