|Table 5. 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
|Based upon visual observation of infected plumeria plants from various places for a
number of years, it seems 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 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.
|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
|Figure 1. Vishanu Gold infected with FrMV
Frangipani Mosaic Virus (DPVWeb)
FrMV (Plant Viruses Online)
FrMV testing service - AC Diagnostics
FrMV testing service - Lynch Diagnostics
The complete genomic RNA of FrMV
*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 or hands are not disinfected afterwards. After infection
with a virus, the virus particles reproduce and move within plant via phloem as well as from
infected cells into neighboring cells, and finally colonize an entire plant (except for meristem). The
first sign of symptom in plant may take months or years to appear (depending upon plumeria
cultivar, and plant's 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
*Extreme heat can put a lot of stress on plant and provides favorable condition for FrMV residing
in the plant to grow. FrMV is more active and replicates quickly at HIGH temperature (best at
30-35Cor 86-95F). It is the VIRUS (not HEAT) that is responsible for these unique viral symptoms
in virused plumeria plant.
*Grafting (especially bud grafting) is another factor that causes a lot of stress on 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.
*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 of various sizes and shapes on the leaves, and dark red/moroon splashes (color breaks) of
various forms and size unevenly 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 "red 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 may change in size, color and
shape as the symptom progresses into surrounding tissue of the leaves.
*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 healthy with symptoms
which occasionally appear on flower and/or leaf. 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 affected by FrMV infection.
|Some plumeria cultivars (such as Miracle, Fire Blast and Gammaam) have flowers with
natural splash. Some other cultivars (such as Madame Poni and Puddha Raksa) may have
natural incurved petals in which anthocyanins tend to overaccumulate (anthocyanescence)
within the incurved area. Unlike FrMV causing splashes, these natural splashes on petals
always locate at about the same place and their patterns are consistant from petal to petal
and flower to flower regardless of the degree of petal incurving (Figures 3 and 4, Table 3).
The anthocyanescent markings of these natural splashes may be sometimes confused with
those caused by FrMV. In FrMV infected plumerias, both FrMV splash and natural splash
may appear on petals of the same flower at the same time, and sometimes are hard to
differentiate one from another (Figure 5 and Table 4). In contrast to natural splash, FrMV
splash patterns are non-consistant from petal to petal and flower to flower. Splash which
locates beyond the boundery of natural splash is likely due to FrMV or something else.
Viral splash appears to be significantly darker in color (dark red/maroon) due to the
overaccumulation of anthocyanin pigments (anthocyanescene) in the presence and high
activity of virus in such areas (Figure 5 and Table 4). In plumeria plants, high intensity light
during warm and dry summer days plays an important role in intentifying or darkening the
overall flower colors including the colors of both natural and viral splashes due to the
increase in anthocyanin biosynthesis rate.
|Important note related to FrMV and Symptoms in Plumeria
|Table 2. Unique Symptoms caused by Virus in some Plumeria Cultivars
Note: FrMV splashes vary in appearance and unevenly exhibit on flower petals and/or leaves, and have non-consistant pattern
from flower to flower (and leaf to leaf).
|Table 3. Coloration and forms of Natural splashes in plumeria flowers
*Notice natural spashes with consistant patterns from petal to petal and flower to flower
|Figure 3. Natural Splash in Madame Poni plumeria -
Anthocyanescent markings within incurved area and
consistant pattern from flower to flower.
|Figure 4. Natural splash in Purple Serendipity plumeria
- Sometimes its flowers may form loosely incurved petals
with (natural) splash within the incurved area. As
shown in this picture, the natural splashes that appear
on petals are always at the same location in all flowers
and have consistant pattern from flower to flower.
|Sometimes other factors can cause symptoms similar to those caused by viruses.
Reddish/purplish coloration (anthocyanescence) found in plumerias is a common plant
response (generally associated with plant's physiological functions) to a wide array of
stress factors. Some of these factors are extreme environment (drought or heat/sunlight),
nutritional deficiencies/excesses, plant abnormalities, chemicals, insect feeding, plant
pathogens (including virus), and etc. (Table 5). Their anthocyanescent markings differ in
form and shape and sometimes may be confused with natural splashes (Table 3) and those
caused by FrMV (Table 2 and 4). Most of the time, virus diseases cannot be diagnosed on
the basis of symptoms alone.
|Virus causing Color Break in Plumeria in Thailand
|Figure 5. Natural and Viral Splashes in Miracle plumeria -
Natural splash: the lighter red bans locate on left side part of
each petal and its pattern is consistant from flower to flower.
Viral splash: the dark red-maroon splashing, and the
non-consistent patterns from petal to petal and flower to flower.
|Natural Splash vs Viral Splash
|Splashes caused by other means
|Table 4. Natural splashes and Viral Splash appear on the same flower
******Click to enlarge the images -- Arrow signs indicated the location(s) of viral splashes
|*Click the image to enlarge - Arrow signs are the
locations of viral splash (dark red/maroon)