Answer:
Explanation:
1. An avirulent pathogen gains enough access to its host plant to enable it to perpetuate itself mildly harm without severely damaging or killing the host plant
2. Avirulent pathogen Not highly infective or likely to cause disease
3. Avirulent - not virulent and unable to produce disease.
4. Infecting a host plant with a strain of virus which causing the host only mild disease symptoms and no severe disease ; known as avirulent strain.
