Amensalism

 What is Amensalism ?

Amensalism is association between two species, in which one species is harmed and other species is unaffected. 

Examples:

1. The mould penicillium creates a substance known a penicillin, this is extremely toxic to bacteria. The mould is unaffected but the bacteria dies.
2. The black walnut secretes a chemical from its roots known as juglone, this harms the neighbouring plants, the black walnut is unaffected.