How to Manage Wheat Streak Mosaic

FBN Network

Dec 20, 2023

Wheat streak mosaic (WSM) is a viral disease that can significantly diminish wheat yield and quality. 

William M. Brown Jr.,

WSM primarily impacts the wheat plant's leaves, causing the characteristic streaks. However, the virus can also infect the stems, roots, and grains. Infected plants often exhibit stunted growth and reduced tillering, leading to substantial yield losses. 

The virus also hampers the plant's photosynthetic ability, further affecting growth and grain production. Infected grains are typically small and shriveled, reducing both yield and quality.

In this post, we’ll cover:

  • How to identify wheat streak mosaic

  • Geographic reach of wheat streak mosaic

  • Timing of wheat streak mosaic emergence

  • How to manage wheat streak mosaic in wheat

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.

William M. Brown Jr.,

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.

William M. Brown Jr.,

Geographic Reach of Wheat Streak Mosaic

WSM is prevalent across global wheat-growing regions. It is particularly rampant in the United States' Great Plains, where it can cause substantial yield losses. 

However, WSM has also been reported in Canada, Australia, Europe, and certain parts of Asia and Africa.

Timing of Wheat Streak Mosaic Emergence

WSM can infect wheat plants at any growth stage, but plants are most vulnerable during the early growth stages. Infections occurring later in the season may not present symptoms until after heading, making them more challenging to identify.

How to Manage Wheat Streak Mosaic in Wheat

The most reliable management option for wheat streak mosaic virus is controlling green-bridge host crops with a burndown herbicide application at least 2–3 weeks prior to planting winter wheat. 

For burndown, apply any of the following at least 14 days before planting: 

Always refer to the product label for the most accurate and up-to-date application rates for your specific situation.

Crop Protection from FBN®

Proactively scouting for and responding to fungal presence in your fields will help reduce potential crop damage and improve yield. FBN has a wide variety of effective fungicides to help address agronomic pressures and keep your operation on track. 

With transparent pricing, straightforward online ordering, detailed product labels and fast direct-to-farm delivery, FBN can help you get the products you need to protect your crops.

Related Resources

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FBN Network

Dec 20, 2023

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