Table 3. Reddish/Purplish coloration (anthocyanescent markings) in Plumeria caused by
means other than virus
According to DPV web, the FrMV transmitted by mechanical inoculation not involving a
vector.
 FrMV hardly spreads in plumerias especially in the wild probably due to the lack
of natural carrier for this particular virus.  Gaining popularity in the past two decades,
plumeria has been vegetatively propagated in mass for sale.  Many growers did not take
any precautions when taking cuttings or making grafts.  Viral-contaminated cutting tools
used in grafting and pruning become the most common means of FrMV transmission.  
Unfortunately, it is how this particular virus spreads rapidly and covertly in plumerias,
especially in Thailand and recently in the plumerias exported to the US and the rest of the
world.  Nowadays, its symptoms are commonly seen in plumerias which are sold in the
markets in a number of countries.  Some virused plumerias may look normal, but the
symptoms generally appear in a later stage.  Thus it is important to address this issue to
increase growers' awareness, to keep the virus under control, and to save all great
plumeria cultivars from being infected.

In an attempt to keep the whole plumeria collection virus-free, newly acquired plumerias
first should be isolated over a period of time to observe or check (test) for the presence
of virus.  All FrMV-infected plants should be separated from the rest of collection and/or
destroyed.  Using a sterilized cutting tool is also the key to preventing the spread of the
FrMV, which may be present in the plumeria trees growing in the garden, to the rest of
the collection.  My routine practice of pruning plumerias in the garden is to carry as many
sterilized knives as possible with me and use only one knife per plumeria plant.  They are
then sterilized in boiling water for further use.

Plumerias with the virus should not be allowed to be registered as a new cultivar
based upon its appearance of the flowers with the color break.  It is just a diseased
plant, not an innovative one.
Based upon field/laboratory tests and observation of infected plumeria plants from
various places for a number of years, it comes into a conclusion that Frangipani Mosaic
Virus has a minimal effect on the growth and the health of most plumerias with the
exception of severe cases in a few cultivars.  Its symptoms may include, e.g., leaf
malformation, mottled leaf, and/or non-uniform splash or color break (CB), especially on
the petals.  Some plumeria trees appear normal with only an occasional CB on the petals,
which is attractive to some people.  From my point of view, however, the color break is
unacceptable since it distorts the original colors of flowers.  In addition, unlike other
diseases, it is incurable, and the virus that resides in the infected plant may accidently
spread to other plumeria trees somehow, and finally, the whole collection may all be
infected.
Viruses are one of infectious pathogens.  Like other plants, plumerias can be infested
with viruses.   The particular types of viruses such as Frangipani Mosaic virus (FrMV)
found in infested plumeria may cause discolorations and/or distortions in leaves and
flowers and stunt the plant growth.  The symptoms are highly variable, depending
on the variety and the environment.  Knowing the nature of FrMV (especially viral
transmission) as well as using precaution when handling the plants are the key steps in
preventing it from spreading.  FrMV and its symptoms found in plumeria in Thailand are
emphasized on this page.  Coloration markings caused by FrMV and by other means are
also mentioned here.
Chompoo Paan plumeria
Plumeria Virus
Rim Fire plumeria Bali Whirl plumeria
Color break (red splash areas) on petals of Rim Fire (left
picture) and Bali Whirl plumerias (right picture) caused by
virus.  
The symptoms on the petals develop as the flowers
emerge.
 Seedlings of the virus infected Rim Fire have no
sign of virus.
Muang Phuang Roi plumeria An unknown very light pink plumeria
Left picture: Color break (darker purple area) on petals of
Muang Phuang Roi plumeria caused by virus.

Right picture: Color break (pink area) on petals of very
light pink flowers.
Coral Cream plumeria
Left picture: Symptoms (dark red spots) on petioles and
stems of Coral Cream plumeria caused by virus.  Notice:

The reddish/purplish areas within the context of normal
coloration.

Right picture: A severe leaf malformation and mottled leaves
in a Thai plumeria caused by virus.  For this particular case,
it stunts the growth of the plant.
New emerging leaf with viral symptom Mature leaf with viral symptom
Mottled/splotchy leaves caused by virus.  Normally
symptoms develop right from the start as new leaves emerge

(left picture).  Then they become lighter in color (fade)
with leaf age (right picture).
An unknown variegated plumeria Namwan plumeria
Left picture: This variegated foliage (light/dark green) is a
form of Chimera.  But the dark brown mottled areas on
the leaf indicted that it is infected with virus.
Right picture: Namwan--a chimeric variegated plumeria
(green on light pink background) often found to be
infected with virus (brown spots throughout the entire
leaf).

Left and right pictures: Viral symptoms (unknown
cultivars)

Left picture: Viral symptom (unknown cultivar)

Right picture: Viral symptom (Moung Phoung Roi
plumeria)

Left picture: Viral symptom (Kled Tabtim plumeria)

Right picture: Viral symptom (Moung Dao Den plumeria)

Left picture: Viral symptom (Roung Siri Chok plumeria)

Right picture: Viral symptom (Dwarf Singapore Pink
plumeria)  Note: Reddening/purpling spots in the picture
are not viral symptom.
Symptoms of virus on newly emerging leaves in
bud-grafted plumerias (left and right pictures).  The scion
used was a bud from a virused plant while the root stock
was an one year old seedling.
One of the most commonly seen cultivars infected with FMV.
Over five inches, heavy textured petal flower
Counter
Kukiat's Garden
Table 1. Symptoms in Plumeria (flower, leaf and petiole) caused by Virus
Note: FrMV Splashes is due to the over accumulation of anthocyanin pigments in flower petal and/or leaf of virused plumerias.
Figure 2. The original color of virus-free
Vishanu Gold
Figure 1. Vishanu Gold infected with FrMV
Transmission:

*FrMV is transmitted primarily through cutting or trimming the plants.  Contact of the infected
plant's sap with sap of a healthy plant will infect the new plant.  This can happen whenever cuts are
made and the cutting/grafting tools, hands or workbenches are not disinfected afterwards.  After
infection with a virus, it enters the vascular system of the plant, and the virus particles (virions) are
formed and transported through plasmodesmata (microscopic channels bettween cells).  In the
process, they spread from the infected cell to neighbouring cell(s) (where more virions are
replicated), and move from one part of the plant to the next, and eventually colonize the whole
plant.  The first sign of symptom in plant may take months or years to appear (depending upon
plumeria cultivar, and plant and environmental conditions).

*
FrMV resides in infected plant throughout the plant's life.  The disease is incurable.  Cuttings
taken from an infected plant are infected even if no symptoms are immediately exhibited by the
cuttings.  The only area in the infected plant that virus can not enter is meristem.  Meristem-tip
culture may be applied to get a new plant with free of virus.

*
FrMV does not transmit through seed, resulting in absence of virus in seedling.  Like all
plumerias, the seedling can be infected with FrMV at any age with poor cultural and sanitation
practices.

Favorable conditions:

FrMV may lie dormant within a cell, and the period of the latency in some plumeria cultivars can
span for a long time without any symptoms on their flowers and leaves.  The mechanism to reverse
the latent state is quite complex involving the interaction between the virus and its plant host.  The
virus is also able to occasionally reactivate via external activators (i.e. stress or the change in
environmental conditions or any other unknown factors) to cause the symptoms to reappear.

*Heat is one of the many factors that can put a lot of stress on a plant, and provides favorable
condition for FrMV residing in the plant to grow.  FrMV is more active and replicates quickly at a
relatively high temperature (best at 30-35C or 86-95F) but at a slower rate when temperature is
outside (lower or higher) of its optimal growth range.  Although the extreme and prolonged heat
(e.g. 100+F) is not the best condition for FrMV to grow, it can put a lot of stress on the plant host.

It is important to note that it is the VIRUS (not HEAT or other external activators) that is
responsible for these unique "viral symptoms" in the virused plumeria plant.  The other words, only
the plumeria plant infested with the FrMV can exhibit the "viral symptoms" when the condition(s)
is right, but the non-virused plant never ever does.

*Grafting (especially bud grafting) is another factor that causes a lot of stress on a plant.  If either
rootststock or scion used in grafting is from virused plant(s), the entire graft is infected.  The viral
symptom likely appears on emerging leaves of the newly grafted plant.  Again, it is the VIRUS (not
GRAFTING) that is responsible for the viral symptom on the leaves.

Symptoms:

The symptoms of viral disease result from the immune response to the virus, which attempts to
control and eliminate the virus from the plant and from cell damage caused by the virus.

*FrMV replication causes a change in color pattern of pigmented flower/leaf by intensification and
overaccumulation of epidermal anthocyanin pigments in the petals/leaves (anthocyanescene).
 (Note:
Anthocyanescence is the development of reddish/purplish hues within the context of normal coloration by the
accumulation of anthocyanin.)

*Looks for the virus lesions on a newly emerging leaf and flower.  These are where the symptoms
first reveal themselves (before evolving further with leaf or flower age) and are a strong indication
of FrMV evidence.

*FrMV affects different plumeria cultivars/species in different ways, so it is impossible to give a
definitive description of symptoms.  Besides plumeria cultivars, the symptoms may vary with plant's
parts (e.g. flower, leaf, petiole and etc.) and viral strains and environmental conditions.  Yet there
are some common characteristics among infected plants; including irregular mottled/splotchy
markings or dark striations of various sizes and shapes on the leaves, and non-uniform dark
red/moroon splashes (color breaks) of various forms and size unevenly/unpredictably distributed on
the flower petals and non-consistent patterns from flower to flower (Table 1 and 2).

Depending on how people view it, the color breaks on flower petals may look like a "dark
red/maroon paint splatter" in painted pictures or "blood splatter" at a crime scene in J105 plumeria
cultivar, or "blood or red paint bleeds" in watercolor in Bali Whirl cultivar.  Unlike flowers, leaves
can stay on the tree for a longer time; therefore, the viral mottled markings or the dark striations
may change in size, color and shape as the leaves expand and the symptom progresses into
surrounding tissue of the leaves.  The color of mottled makings generally fades when the leaves
mature and age.

*Infection does not always result in visible symptoms at all time.  In case of having visible
symptoms, they may exhibit only on either flowers or leaves or disply on both flowers and leaves at
the same time.  In case of Plumerias (eg. P. alba) with pure white flowers (no anthocyanin
pigment), the symptom only appears on leaves.

*FrMV does not kill plumeria plant.  Most virused plumerias are apparently normal with symptoms
which
occasionally appear on a few flowers and/or a few leaves.  Some cultivars may frequently (or
hardly) exhibit symptoms especially the color breaks on flower petals.  However, the growth of a
few cultivars may be
severely impaired by FrMV infection.
Viral Symptom
Viral Symptom
No Viral Symptom
Cultivar names
Under construction
J105
Under construction
Phoung Yok
Dwarf Singapore
Pink
Under construction
JL Metallica
Under construction
Confetti
Rim Fire
Bali Whirl
Celadine

(notice the
variation in size
and shape of the
symptoms)
Under construction
Lava Flow
My Valentine
Vishanu Gold
Under construction
Veracruz Rose
Gammaam
Note: Red coloring at
the center is natural
splash (column 3).
Under construction
Puddha Raksa
Note: Red coloring
seen on each petals
are natural splash
(column 3).
Heat/Sunlight: UV-B radiation

The colors of flowers are intensified with the high temperature.  
Exposure to UV-B (that comes with sunlight/heat) increases anthocyanin
levels in the plumeria flowers.

Upper and Lower Left: Penang Peach, Heirloom and Mardi Gras
plumerias in cool season.

Upper and Lower Right: Penang Peach, Heirloom and Mardi Gras
plumerias in warm month.
Notice The increase in anthocyanin
accumulation in the entire area of petals under the exposure of UV
radiation.

Note: FrMV also causes the anthocyanin to accumulate but with greater
intensity, and the lesion markings on petals located ONLY in the area(s)
where the virus is highly active.  Click to view the image of
Virused
Penang Peach
Reddening/purpling coloration: Fungus

Reddish coloration in association with unidentified pathogenic fungus on
an unknown and Slaughter Pink plumeria flowers
Reddening/purpling coloration: Fungus

Reddish spots in association with unidentified pathogenic fungus on
aging plumeria flowers
Under construction
Reddening/purpling spots: Chemicals and sunlight

Reddish specks developped on a flower of Pink Pancy plumeria after
being sprayed with insecticides (Chlorpyrifos and imidacloprid) and
being exposed to a day of direct summer sunlight.
Reddening/Purpling coloration: High light-intensity

High light-intensity during hot summer months stipulates anthocyanin
biosynthesis.  Anthocyanin pigments are produced in the stems and
leaves of the sun shoots (left picture). These red pigments help to
protect the chlorophyll from excess ultra-violet radiation.  The increase
in anthocyanin pigments under this condition also resulted in darkening
the colors of plumeria flowers.
Reddening/Purpling coloration: Senescence

It is common for the cultivars with high anthocyanin content to develop
reddish/purplish markings on leaves.  They start to appear on leaves at
young stage but almost fully extended (Top and bottom left pictures),
and become more intense in color when fully mature (Top and bottom
right). (note: Orange pustules are Frangipani rust.)

Entering the senescence stage, the coloration appears on leaves of some
plumeria cultivars late in the season (when daylight hours shorten and
temperatures drop) before heading into dormancy in winter.
*Continue on next row....
*continued from the row above...
Reddening/Purpling coloration: Anthocyanescence + fungus infestation
After the anthocyanescent markings being formed, lesions may later
develop within the boundary of these markings, and turn brown with leaf
age.  The lesions may be in association with fungus infestation.

Left/Middle: Early signs of lesions within anthocyanescent markings on
underside and can be seen on the opposite side (upperside) of leaf (Heart
of the Night plumeria).

Top right: Lesions within anthocyanescent markings on underside
Bottom right: The opposite site (upperside) of the same leaf
Reddening/purpling coloration being formed after having lesions:

The circular lesions of unknown cause (Top left) may develop on the
underside of very young leaves and turn brown as the leaf matures (Top
right).  Purplish coloration around the lesions on the upperside develops
at a later stage (Bottom right) (Edelstein plumeria).

Top left: Circular lesions on underside of very young leaf
Bottom left: No purplish coloration on the opposite side (upperside) of
the same young leaf
Top right: Brown circular lesions on underside of mature leaf
Bottom right: Lesions with purplish coloration on the opposite side
(upperside) of the same mature leaf
Atypical reddish/purplish coloration associated with Frangipani rust
lesions:

With time, the areas infested with frangipani rust pustules turn into
brown lesions (Top left and Right pictures) which can be seen on the
upperside of leaf (Bottom left picture).  Atypical reddish/purplish
coloration may deveolop around the tissues in association with the sites
of infection and disease lesions. (Bottom left and right pictures)
Reddening/purpling in association with lesion caused by Broad mite:

Anthocyanin biosysthesis is stimulated by broad mite injury.  As a result,
the dark red/maroon colored pigments of anthocyanin accumulate in the
infected areas of distorted/curled leaves.  This coloration phenomenan
mostly happens only in plumerias with leaves that are rich in anthocyanin
like Doric, Marble Ice Cream and etc.
Note: This may be sometimes confused with the coloration caused by
FrMV in virused plant.  (For the case of FrMV symptom in plumeria, the
leaves hardly curl or twist).
Under construction
Atypical reddish/purplish coloration associated with Powdery mildew
disease
Under construction
drought/strong sunlight/nutritional deficiencies/plant abnormalities
FrMV and Symptoms in Plumeria
Table 2. Unique Symptoms caused by Virus in some Plumeria Cultivars
Note: FrMV splashes vary in appearance size and shape, and romdomly and unevenly exhibit on flower petals and/or leaves,
and have non-consistant pattern from flower to flower (and leaf to leaf).
Apart from the FrMV, the levels of anthocyanin accumulated in some particular parts of
plumeria flower and leaf can also be influenced or caused by other factors.  The
reddish/purplish coloration being formed is generally a common plant response (associated
with plant's physiological functions) to heat/sunlight or UV-B radiation, nutritional
deficiencies/excesses, plant abnormalities, chemicals, insect feeding, plant pathogens
(including virus), wounding and etc. (Table 3).   The anthocyanescent markings formed
after being exposed to these factors are quite different in forms, sizes and shapes, and to
the untrained eye they may be mistaken for other kinds of markings such as natural
splash, chimeral splash (see
Splashes in Plumeria) and those caused by FrMV (Table 1 and
2).
Virus causing Color Break in Plumeria in Thailand
Splashes caused by means other than FrMV