Which scientist experimentally proved that DNA is the sole genetic material in bacteriophage ?

The unequivocal proof that DNA is the genetic material came from the experiments of Alfred Hershey and Martha Chase. They worked with viruses that infect bacteria, called bacteriophages. They discovered that it was DNA from the viruses that entered the bacteria.

(1) Beadle and Tatum’s contribution to genetics was the “one gene-one enzyme hypothesis,” stating that each
Gene is responsible for producing a specific enzyme, which revolutionized our understanding of the relationship between genes and proteins.
(2) Masselon and Stahl’s contribution was the experiment that provided strong evidence for semi-conservative DNA replication.
(4) Jacob and Monod’s contribution was the discovery of the Lac operon model and the concept of gene regulation in bacteria.