Blight
Casting Time
              
          Range
              
          Target
              One creature or plant
          Components: 
      
    Duration: 
          
          
    Instantaneous
 
            Saving Throw
              Constitution halves
          Necrotic energies drain moisture and vitality from the target, dealing 8d8 necrotic damage. Undead and constructs are immune to this spell.
A plant creature or magical plant has disadvantage on its saving throw and takes the maximum damage possible from this spell. A nonmagical plant that isn’t a creature receives no saving throw and instead withers until dead.
Cast at Higher Levels
              The damage increases by 1d8 for each slot level above 4th.
Source