Which of the following is an example of a heteroecious rust fungus?

-✅Explanation: A heteroecious rust fungus is one that requires two different host plants to complete its life cycle. Rust fungi alternate between a primary host (typically an economic crop) and an alternate host (often a wild plant).
-Cause: A true rust fungus.
-Host requirement: Heteroecious, requiring wheat (primary host) and Berberis spp. (alternate host) to complete its life cycle.
-Symptoms: Causes black pustules (uredospores and teliospores) on wheat and affects Berberis with pycnia and aecia stages.

-Other Options

• White rust of mustard (Albugo candida):
-Cause: A fungal-like organism (oomycete) rather than a true rust fungus.
-Host requirement: Completes its life cycle on a single host (autoecious).

• Linseed rust (Melampsora lini):
-Cause: A true rust fungus.
-Host requirement: Autoecious, completing its life cycle on linseed/flax.

• Pea rust (Uromyces pisi):
-Cause: A true rust fungus.
-Host requirement: Autoecious, completing its life cycle on pea plants.