The sum of the qualities of the host and causal agent that retard the activities of the causal agent.
The crab-apple trees in the foreground have scab but the tree on the left has much more foliage since it is a resistant type. (The sycamores in the background have lost many leaves due to anthracnose).
Jay W. Pscheidt, 2010.
The sum of the qualities of the host and causal agent that retard the activities of the causal agent.