Correct diagnosis of any plant disease requires some expertise. Plants suspected of a viral infection should be sent to a plant disease diagnostic laboratory. One of the specific tests that a plant diagnostic laboratory might perform is an
ELISA or serological test where the plant sap is tested against virus specific
antiserum made to the
capsid protein of the virus. A
PCR test can also be run using the
RNA of the virus. A part of the viral
genome can be copied and sequenced and then compared to sequences of other potyviruses in the
GenBank. If the sequence of the segment matches to a known sequence at 90% or greater it can be assumed the virus in the plant is that same virus. A third way used to diagnose some plant viruses is to inoculate a variety of other plants and match the known host range for a given plant virus. In addition, plant viruses make
inclusion bodies in plant cells that can be stained and seen in a
light microscope. Bidens mottle has a distinctive host range and makes typical potyvirus inclusions. One of the diagnostic hosts for this virus is the plant
Zinnia elegans. The virus makes easily recognizable viral inclusions called
laminated aggregates and prominent symptoms on both the leaves and the flowers of this plant.) ==Geographic distribution==