The steps that must be taken by the scientist to transfer the gene to orange trees to protect them from pathogens is the modified virus must be introduced to the orange trees' cells.
Pathogens may be defined as those microorganisms which are capable of causing diseases in other organisms.
When a gene of defensin protein is introduced into the virus, it also becomes protected against microbial infection.
This modified virus is then injected into the genome of the orange tree which in result leads to highly tolerable to microbial infections.
Therefore, the steps that must be taken by the scientist to transfer the gene to orange trees to protect them from pathogens is the modified virus must be introduced to the orange trees' cells.
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