Evidence of milkweed yellows phytoplasma? - Ask Extension
Hello. There is common milkweed growing in the island of a cul de sac in my neighborhood. While many of the plants look normal, quite a few patches re...
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Evidence of milkweed yellows phytoplasma? #873457
Asked June 17, 2024, 2:07 PM EDT
Hello. There is common milkweed growing in the island of a cul de sac in my neighborhood. While many of the plants look normal, quite a few patches resemble what is displayed in the attached photo. I am wondering if this looks like milkweed yellows phytoplasma? Many thanks!
Kalamazoo County Michigan
Expert Response
Hello Cameron,
Aster yellows affects hundreds of plants. It is carried from plant to plant by a tiny insect called aster leafhopper.
Aster yellows is caused by a tiny organism called a phytoplasma, similar to a bacterium. The phytoplasma is carried from plant to plant by leafhoppers. The leafhopper acquires the phytoplasma by feeding on the phloem cells of an infected plant. It then transmits the bacterium to another plant when it feeds again. Multiplication of the organism occurs within the leafhopper, so the insect can transmit the disease throughout its life—which is 100 days or longer. https://extension.umn.edu/yard-and-garden-news/aster-yellows
The aster yellows phytoplasma moves systemically through the plant, infecting every part from the roots through the flowers. The pathogen affects the plant’s growth, development, and ability to store nutrients. There is no cure for aster yellows.
The following article from the University of Minnesota gives an excellent explanation of aster yellows.
https://extension.umn.edu/plant-diseases/aster-yellows
If you suspect a plant has aster yellows, the only way to confirm this is with a diagnosis from a lab. You can send a sample to the MSU diagnostics lab at pestid.msu.edu.
I'm not sure that this is aster yellows. There are a number of causes for yellow leaves: Early Blight (fungus); Shading of the bottom leaves; Low nitrogen, potassium, or other nutrients; and aster yellows.
You can watch the plant for a few weeks to see if the plant shows additional signs, or you could send a sample to the diagnostic lab for a definitive identification. Since the plant is not on your property, you probably can't take a soil test to check for nutrient deficiencies.
I hope this information helps, but don't hesitate to contact us again if you have questions or need more information.
Have a nice weekend.
Aster yellows affects hundreds of plants. It is carried from plant to plant by a tiny insect called aster leafhopper.
Aster yellows is caused by a tiny organism called a phytoplasma, similar to a bacterium. The phytoplasma is carried from plant to plant by leafhoppers. The leafhopper acquires the phytoplasma by feeding on the phloem cells of an infected plant. It then transmits the bacterium to another plant when it feeds again. Multiplication of the organism occurs within the leafhopper, so the insect can transmit the disease throughout its life—which is 100 days or longer. https://extension.umn.edu/yard-and-garden-news/aster-yellows
The aster yellows phytoplasma moves systemically through the plant, infecting every part from the roots through the flowers. The pathogen affects the plant’s growth, development, and ability to store nutrients. There is no cure for aster yellows.
The following article from the University of Minnesota gives an excellent explanation of aster yellows.
https://extension.umn.edu/plant-diseases/aster-yellows
If you suspect a plant has aster yellows, the only way to confirm this is with a diagnosis from a lab. You can send a sample to the MSU diagnostics lab at pestid.msu.edu.
I'm not sure that this is aster yellows. There are a number of causes for yellow leaves: Early Blight (fungus); Shading of the bottom leaves; Low nitrogen, potassium, or other nutrients; and aster yellows.
You can watch the plant for a few weeks to see if the plant shows additional signs, or you could send a sample to the diagnostic lab for a definitive identification. Since the plant is not on your property, you probably can't take a soil test to check for nutrient deficiencies.
I hope this information helps, but don't hesitate to contact us again if you have questions or need more information.
Have a nice weekend.
