Asparagus spears are usually harvested before severe rust symptoms appear. These symptoms include light green, oval lesions, followed by tan blister spots and black, projecting blisters later in the season and indicate the presence of aeciospores, urediospores, and teliospores, respectively. Serious rust infections stunt or kill young asparagus shoots, causing foliage to fall prematurely, and reduce the ability of the plant to store food reserves. The orange spores are the key sign for this disease because they are the easiest to spot. Examination of the plant for orange spots or laboratory techniques can sense the presence of this fungus.
Plant Protection Products