Impatiens Necrotic Spotted Wilt Virus (INSV)

Pathogen: Impatiens Necrotic Spotted Wilt Virus (INSV)

Hosts Include: Ajuga, Aster, Campanula, Delphinium, Dianthus, Digitalis, Echinacea, Gaillardia, Gaura, Heuchera, Hosta, Leucanthemum, Lobelia, Lysimachia, Monarda, Oenothera, Penstemon, Phlox, Platycodon, Primula, Salvia, Scabiosa, Sedum, Tradescantia, and Veronica

Symptoms: Symptoms vary depending on the host but may include necrosis and spotting, ringspots, mosaic, mottling, distortion of new growth, stunting and plant death.

Spread: INSV is spread by western flower thrips. Once a thrips acquires INSV it can vector the virus to susceptible hosts it feeds on throughout its lifetime. The pathogen can also be spread by sap transmission. Plants can be infected and show no symptoms, the virus can be spread from these plants. INSV can overwinter in the roots of infected plants.

Management: Scout incoming plant material for signs of disease and for thrips.  Susceptible plants should be scouted regularly for thrips (see thrips section for more information). Avoid intermixing of more and less susceptible crops within the same greenhouse, also avoid intermixing of seed and cutting-propagated crops. Eliminate weeds from the propagation area. Immediately remove symptomatic plants from the growing area. Diagnostic testing can be done by a plant diagnostic lab or at the growing facility with testing strips available from plant diagnostic companies.

Begonia with ringspots on foliage
New Guinea impatiens foliage showing mottling and distortion
Bracteantha bracteata with mottled foliage
Shasta daisy with distorted foliage
INSV can cause severe distortion of foliage

For more information visit:

Plant & Pest Diagnostics

Other Documents in this Series

Accessibility Questions:

For questions about accessibility and/or if you need additional accommodations for a specific document, please send an email to ANR Communications & Marketing at

Michigan State University Michigan State University Close Menu button Menu and Search button Open Close