What host plants are commonly affected by oak root fungus?

Oak root fungus, known scientifically as Armillaria mellea, primarily targets trees and woody plants, particularly those in the oak family and related species. The correct choice identifies host plants such as grapes, walnuts, and pears, which are susceptible to the disease caused by this pathogen.

Grapes and walnuts are both commonly grown in areas where oak root fungus is prevalent, particularly because these trees often share ecosystems with oaks. Pears, while not directly related to oaks, can also fall within the range of plants that oak root fungus affects, particularly when they are grown in similar soil conditions.

Recognizing the specific relationship between oak root fungus and its preferred host plants is essential for effective management and control strategies in agricultural and gardening practices. Monitoring symptoms and implementing preventative measures are crucial for reducing the impact of this pathogen on the plants mentioned.

The other options present crops that either are not significantly affected by oak root fungus or grow in different ecological niches that do not overlap with oak trees, making them less relevant to the question of host susceptibility.