How to Identify Wheat Streak Mosaic
The first line of defense against WSM is its accurate identification. Misdiagnosis, often confusing WSM symptoms with nutrient deficiencies or other diseases, can lead to ineffective management strategies.
WSM-infected wheat plants manifest a range of symptoms. The most prevalent is the emergence of light green to yellow streaks on the leaves, typically running parallel to the leaf veins. These streaks may merge over time, creating a mosaic pattern on the leaf. In severe cases, these streaks can appear on leaf sheaths, and the entire plant may yellow.
Beyond the characteristic streaks, WSM-infected plants may exhibit stunted growth, reduced tillering, and premature death. The disease may also lead to the production of small, shriveled grains or even prevent grain production entirely.
While the distinctive leaf streaks are the primary identifiers of WSM, laboratory tests such as ELISA or PCR may be necessary for confirmation. It's crucial to remember that symptoms may vary based on the wheat variety and the growth stage at the time of infection.
(Image Credit: William M. Brown Jr., Bugwood.org)