Question

Extract of tobacco with the mosaic disease was called contagium vivum fluidum by
A) Mayer
B) Ivanowski
C) Beijerink
D) Pasteur

Answer 1

Hint: Tobacco mosaic disease is a viral disease caused by mosaic virus and hence the name contagium vivum fluidum should be given by a virologist based on the character of the virus itself.

Complete answer: Let us look into the options to get the answer for the given question.
Option A is Mayer. He was a renowned taxonomist and his main contributions were in evolutionary biology. So this is not the correct answer.
Option B is Ivanowski. He recognized certain microbes as causal organisms of the mosaic disease of tobacco that were found to be smaller than bacteria because of the past through a bacteria proof filter.So, this is not the correct answer
Option C is Beijerink. He was the famous Dutch microbiologist and a virologist. While studying the tobacco plant, he thought of studying the cause of the mosaic disease on the tobacco plant. He realized that it was a different kind of microorganism that caused the mosaic disease. He experimented with the extract of that tobacco plant which was diseased by the mosaic virus and started studying the character of the cause of mosaic virus, he found that the micro organism involved is fluid in nature which is nothing but contagium vivum fluidum. So,this is our correct answer.
The option D is Pasteur. The name 'virus' to the viral organisms that means Venom or poisonous fluid was given by Pasteur.So this is not our correct answer.
Additional information: Beijerink got into the deeper learning about the cause and found that it wasn't bacteria but virus and accompanied his research with the fluid nature of the virus. When he tried passing that microorganism through the finest mesh filters, the microorganism passed through it showing its liquid properties which is nothing but Contagium vivum fluidum .
Contagium vivum fluidum is nothing but a phrase that means that the virus is infectious living fluid in nature.

So, the correct answer will be option C.

Note: So from the above discussion it can be concluded that contagium vivum fluidum was given on the basis of infectious fluid living character of virus (based on the observation of Beijerink on the tobacco plant).
Sometimes the confusion may arise between Beijerink and Pasteur, but the correct answer to be remembered is Beijerink only.