In-situ conservation means "on-site
• It is the process of protecting an endangered plant or
animal species in its natural habitat, either by protecting
or cleaning up the habitat itself, or by defending the
species from predators.
• This term refers also to the conservation of genetic
resources in natural populations of plant or animal
species, such as forest genetic resources in natural
populations of tree species, and is increasingly being
applied to conservation of agricultural biodiversity in
agroecosystems by farmers, especially those using
unconventional farming practices.
Ex-situ conservation means
literally, "off-site conservation".
• It is the process of protecting an endangered
species of plant or animal outside of its natural
habitat; for example, by removing part of the
population from a threatened habitat and placing
it in a new location, which may be a wild area or
within the care of humans.
• While ex-situ conservation comprises some of
the oldest and best known conservation
methods, it also involves newer, sometimes
controversial laboratory methods.
Rafflesia Life History
• " a penetrating smell more repulsive than any buffalo
carcass in an advanced stage of decomposition"
(Mjoberg, 1928) There are approximately 17 Rafflesia
species distributed throughout Southeast Asia (Nais,
2000; Meijer, 1997; Mat Salleh, 1991).
• These species are highly specific as to the hosts that
they parasitize, preferring only a few species of
Tetrastigma (a member of the common grape family)
that are distributed in the same geographic area.
• Although technically a member of the plant kingdom,
Rafflesia challenges traditional definitions of what a plant
is because they lack chlorophyll and are therefore
incapable of photosynthesis (as are all members of its
• While many parasites appear like normal plants,
Rafflesia lacks any observable leaves, roots, or even
stems (Meijer, 1993). Likened to fungi, Rafflesia
individuals grow as thread-like strands of tissue
completely embedded within and in intimate contact with
surrounding host cells from which nutrients and water
are obtained (Mat Salleh, 1996).
• Perhaps the only part of Rafflesia that is identifiable as
distinctly plant-like are the flowers; however, even these
are bizarre because they attain massive proportions (up
to 3 ft in diameter) and are usually reddish-brown and
stink of rotting flesh.. Although parasitic, Rafflesia
species do not typically kill their hosts in spite of the
drain on resources that they cause.
• . Pollination in Rafflesia has been studied
(Beaman et al., 1988) but is likely a rare event
due to the several factors. The flowers are
unisexual and single sites usually produce either
male or female flowers (see exception below).
• Therefore, in order to have effective pollination
(reproduction), male flowers must be in close
proximity to, and open at the same time as
female flowers so that flies (or any other insect)
can transfer pollen.
Challenges to Studying Rafflesia
• First, individuals grow entirely embedded within the body of the host
plant that they parasitize (Kuijt, 1969). As such, Rafflesia individuals
are only visible when they erupt from within the host body as a
flower bud. Although traditional means of studying Rafflesia, like
anatomical sectioning, could be performed, this method would likely
result in death of both the host and parasite.
• Second, Rafflesia is rare in occurrence and can only be found in
relatively remote lowland forests of Southeast Asia. In this
region, much of its habitat has been converted to farm land or timber
concessions and in some parts of its range, the buds are harvested
and sold for their purported medicinal qualities.
• Third, even once Rafflesia individuals become visible as
flowers, these only survive a few days before decomposing. All of
these factors make it difficult to even find Rafflesia sites and even
when they are known, the sites are often not protected so there is no
guarantee that they will exist in subsequent years.
Rafflesia arnoldii bud, one day
• Unlike other parasites that are important to study due to the
economic loss they cause to important crops, Rafflesia causes
economic benefit through ecotourism: thousands of people go to
Sabah (Malaysian, Borneo) annually hoping to see Rafflesia blooms
(Nais & Wilcock, 1998).
• For this reason, there is great interest in conserving Rafflesia sites
rather than eradicating existing populations (as is the case for
noxious parasitic plant weeds).
• Although preserving as much of its habitat as possible would be the
simplest and most obvious way to conserve Rafflesia, this is not
currently practical throughout its range. Therefore, there is a need to
investigate key questions that will establish priorities for ex situ (not
natural habitat) propagation, management of currently protected
sites and procurement of unprotected sites, and in situ (within
natural habitat) breeding programs.
• Rafflesia Arnoldii can only grow in the undisturbed rain forest in
Southeast Asia mainly in Borneo and Sumatra Islands. Several
species are known to have grown in these areas. In
Bengkulu, where the plant was first discovered, the flower can be
found in Taba Penanjung, a natural reserve 44 km north of
Bengkulu, a city in southern part of Sumatra Island.
• Locally known as “patma raksasa” or giant flower, Rafflesia Arnoldii
that grows in Bengkulu has weight up to 11 kilograms and diameter
of around one meter. The flower with its five petals let out a
disturbing odor just like the smell of dead body in an advanced stage
of decomposition. The strong smell is needed to attract flies to
transfer pollen from one flower to another. Although categorized as
plant, Rafflesia does not have roots, stems, leaves and chlorophyll.
The only part that makes it look like plant is its massive reddish
• Rafflesia is a parasite as it lacks the ability to photosynthesize. They
parasitize few species of Tetrastigma (some kind of grape). Rafflesia
has roots embedded within the host cell from which it obtains water
and other nutrients. However, Rafflesia does not kill its host.
• Pollination is rare because the flower is unisex. Unless there is a
male flower in close proximity to a female flower that opens at the
same time as the male flower so flies could transfer pollen, no
pollination will occur. Once pollination does happen, it takes months
for the bud to bloom with mortality rate of 80-90% and the flower will
only last for five to seven days only. The best time to see the flower
is during the month of September to December.
• In the last decade, the primary forest of Sumatra and
Borneo, the main habitat of Rafflesia Arnoldii had been
converted to timber concession or farmland. With the
forest disappearing at an alarming rate, it can be
assumed that the number of surviving Rafflesia Arnoldii
is decreasing rapidly as well. In the next few years, it is
feared that this plant can become extinct.
• In addition, the sites where Rafflesia flower grows is not
protected. Thus there is no guarantee that the flower will
grow again on the same sites in the coming years. To
make matters worse, local people often harvest the buds
to be used as medicine.
• Something obviously needs to be done to
preserve this unique plant. Conserving the forest
is critical although in many situation not always
• Other ways to avoid extinction is by protecting
the existing Rafflesia sites to enable an in situ
breeding program so the flower could grow over
and over again on the same sites.
• In addition to the in-situ program, ex-situ
propagation can also be arranged by recreating
the species environment outside its natural
Rafflesia photos from Poring in Kinabalu