Phytoplasma

1.  Doi et al., (1967)
 Mulberry dwarf
disease in Japan
 Mycoplasma-like
organisms (MLOs)
 Phytoplasma- 1994 at
the 10th congress of
the International
Organization of
Mycoplasmology

2. Division: Firmicutes
Class: Mollicutes
Order: Acholeplamatales
Family: Acholeplamataceae
Genus: Candidatus Phytoplasma

3. Phytoplasma are specialized bacteria that
are obligate parasites of plant phloem
tissue
They cannot be cultured in vitro in cell-free
media.
 They are characterized by their lack of a
cell wall & bound by triple layered
membrane- protein
 Pleiomorphic or filamentous shape

4.  Size- less than 1 micrometer,
 They have very small genomes-DNA
 Require sterol for the growth
 Formed fried egg colonies on solid media
 Transmitted by insects – hopper ,Jassids
and plant lice and sap and grafting
 Sensitive to tetracycline
 Positive blue staining to Diene's stain

5. Little leaf Phyllody
Witches broom
Yellows

6. The phytoplasma are mainly spread by
leafhoppers, plant hoppers and jumping
plant lice
leafhoppers Plant hoppers
Plant lice

7.  Dodder (Cuscuta spp)

8.  leaf hopper (Cestius
phycitis)
 Affected plants
produce tiny yellow
leaves
 do not bear fruits,
 bushy growth of plant

9.  All floral parts are transformed into green
leafy structures
 In severe infection, the entire
inflorescences is replaced by short twisted
leaves closely arranged on a stem with
short internodes, abundant abnormal
branches bend down.
 Finally, plants look like witches broom.
 Vector: Orosius albicinctus

11.  premature drop of most of
the fruit
 blackening of newly
opened inflorescences
 ascending yellowing of the
leaves (from the lower to
the upper)
 spear leaf death and
collapse, with possibly a
few green leaves
remaining
 fall of the whole crown,
leaving a bare trunk or
‘telephone pole’
 Leaf hopper Myndus
crudus - vector

12. Dwarfing and Yellowing
Bushy appearance
Sterility
Cuscuta
Green leaf hopper

14. Leaf hopper
Infected sett

15.  leafhopper vectors Nephotettix sp.