New Guinea Impatiens: Impatiens Necrotic Spot Virus (INSV)

Stunted plants and distorted leaves with dark green to black blotches, dark streaks, and necrotic concentric rings were observed on New Guinea impatiens (Impatiens hawkeri). This Alert describes and provides photos of Impatiens Necrotic Spot Virus (INSV) on New Guinea impatiens. To confirm INSV, submit plant samples to your preferred diagnostics lab.

by W. Garrett Owen - wgowen@msu.edu

New Guinea impatiens (Impatiens hawkeri) are popular spring bedding plants started from unrooted cuttings or seed and grown in various sizes of containers and hanging baskets for their copious floral display and sometimes, variegated foliage. During recent greenhouse visits, multiple crops of New Guinea impatiens were inspected because of stunted and distorted growth. Upon closer inspection of the stunted New Guinea impatiens plants with distorted leaves, dark green to black blotches, dark streaks, and necrotic spotting and concentric rings were observed.

The magnitude of severity varied among New Guinea impatiens crops. Multiple plants exhibiting different symptomology and signs of a virus infection (concentric rings or spots) was submitted to Michigan State University’s Diagnostic Services lab for testing. Plants were tested with an enzyme - linked immunosorbent assay (ELISA) test. The plants tested positive for Impatiens Necrotic Spot Virus (INSV).

Read the full e-Gro Alert here.