Napier Grass Stunt ► How to tell the difference
The contrast between unaffected
and diseased plant parts is very
important in field diagnosis.
Left: the unaffected, sturdy
shoot is greener than the yellow,
thin diseased shoots either side.
Right: the vigorous young shoots
are more robust than the weedy
shoots that proliferate at the base
of diseased clumps. Contrast
bottom left, diseased, with
bottom right, unaffected.
Below: Differences exist between
the yellow leaves on the right and
the unaffected, green leaves,
though they are both similar in
size and form.
We say ‘unaffected’ rather than
‘healthy’ since the phytoplasma
can be present without any
symptom expression.
Red triangle: diseased. White triangle: unaffected. We gratefully acknowledge the assistance of Namulonge Research
Institute, Uganda in obtaining these photographs. Napier grass is also known as elephant grass.
TEXT: Eric Boa and Phil Jones. PHOTOS: Eric Boa. GLOBAL PLANT CLINIC [www.globalplantclinic.org] 6 July 2005