ISSN: 1412-033X (printed edition)
Volume 11, Number 3, July 2010
ISSN: 2085-4722 (electronic)
Purwodadi Botanical Garden, Indonesian Institute of Sciences (LIPI), Jl. Raya Surabaya-Malang, Km 65, Purwodadi, Pasuruan 67163, East Java,
Indonesia. Tel./Fax.: +62- 341-426046. email:
Manuscript received: 3 June 2010. Revision accepted: 22 July 2010.
Mudiana D, Ariyanti EE (2010) Flower and fruit development of Syzygium pycnanthum Merr. & L.M. Perry. Biodiversitas 12: 124-
128. Flower formation is a process of flowering plant in order to produce the next generation. Flower plays a major role in pollination
and fertilization as early stage of fruit and seed formation. Syzygium pycnanthum is a member of family Myrtaceae or known as ‘Jambu-
jambuan’ family. The research aim was to observe the development process of flowering and fruiting phase of S. pycnanthum at
Purwodadi Botanical Garden. It has been noted that this species has ten (10) stages of flowering and fruit development, namely flower
bud initiation, flower bud fully emerge, unfolding calyx, visible corolla, bud starts blooming, early blooming, perfectly blooming,
perianths and anthers fall, early fruit structure and ripe fruit. All these stages require 80-89 days.
Flower is a vital organ of flowering plants. This organ
is not only important as an identification instrument, but
also plays a major role on reproduction. Every plant has
floral character, both
physiological characters. The differences in shape and
color of flowers are the effect of adaptation process of
certain species to survive. This is also related to the
pollinators that help the pollination of the flowers (Boulter
et al. 2006). Plant responses to their environment are
correlated to the periods of their development. The science
dealt with this issue is phenology.
Basically, flower and fruit development are divided into
6 phases, i.e. (1) flower induction, (2) flower initiation, (3)
pre-anthesis, (4) anthesis, (5) pollination and fertilization
and (6) fruit formation, fruit ripening and seed formation
(Ratnaningrum 2004). However, these phases are different
among the species, which depend on the interaction
between internal and external factors. The external factors
include temperature, light intensity, humidity and minerals;
while the internal factors contain phytohormone and
genetic characters. The interaction between the internal and
external factors give an impact to whole flowering process,
such as flowering periods, juvenility, dormancy, irregular
bearing or irregular fruiting time at the same period (Ashari
environmental indications such as temperature, humidity or
irradiance are known to have an effect on different aspects
of flowering phenology. For an instance, Rahayu et al.
(2007) reported that the initiation flowering process of
Hoya lacunosa was influenced by external factors, i.e. the
average and the variation of daily temperature, light
intensity and humidity.
One of flowering plant collections at Purwodadi
Botanical Garden is Syzygium pycnanthum Merr. & L.M.
Perry. It has potential as an ornamental plant based on its
floral and fruit characters. Moreover, this species had
flowering time throughout the year as stated by Backer and
Bakhuizen van den Brink (1963); this was also the case in
This research aim was to observe the phase of flower
and fruit development of S. pycnanthum. The information
obtained was expected to be a basic reference for further
research related to this species.
The research was done at Purwodadi Botanical Garden
(Purwodadi BG) on February-May 2009 at bed (location
number) XXII. It was rainy season. The climatic pattern of
Purwodadi during the latest three years was shown in
Figure 1. Purwodadi BG is located in Purwodadi Village,
Purwodadi Sub District, Pasuruan District, East Java
Province. It is sited on west direction of Gunung Baung at
300 m asl., about 65 km from Surabaya and 20 km from
Malang. It has type C climate (based on Schmidt and
Ferguson’s) with annual rainfall 2,366 mm at average.
(Arisoesilaningsih and Soejono 2001).
This research was conducted by observation using
instruments such as writing tools, ruler, label paper and
digital camera to help the observation and to compile data.
The observation of plant collection was carried out at bed
XXII.F.4. This collection origin was Mt. Pandan forest,
Madiun District, East Java. It was planted on 31 January
1985 therefore it was about 25 year-old at the time of
observation. The height was 6.5 m with diameter at breast
height 22 cm and the crown width 3-4 m.
First observation was done to know the phases of
flower and fruit development generally, then the picture of
flower development at each phase was taken. Furthermore,
the sketch was drawn based on this picture. The next step
was to determine which flower to be observed in more
details. Five flowers on the same plant were chosen. Labels
were tied on the observed objects. The observation dates
were recorded on the labels. The observation was carried
out daily from the buds emerged until the fruits produced
RESULT AND DISCUSSION
Taxonomy of S. pycnanthum
Syzygium Gaertn. is a member of Myrtaceae with a
large number of species; it can be found from Africa
eastwards to the Hawaiian Islands and from India and
southern China southwards to southeastern Australia and
New Zealand. The most recent study on Syzygium’s
infrageneric classification was done by Craven and Biffin
(2010). They distinguished genus Syzygium into six (6)
subgenera; one of them was subgenus Syzygium where S.
subgenus Syzygium was characterized by usually open
inflorescence, rarely congested and head-like; ovules c. (3-
)8-60(-90) per locule, arranged irregularly or rarely in two
longitudinal rows (Craven and Biffin, 2010).
Morphological characters of Syzygium pycnanthum
The S. pycnanthum’s habit is small tree with diameter
c.a. 20 cm and height 15-20 m. In nature, it can be found at
50-1600 m above sea level in primary or secondary forest
(Backer and Bakhuizen van den Brink 1963). Flowers were
arranged in terminal or auxiliary inflorescences. The
inflorescence was set on a dense panicle. The flower has
short pedicel (3-4 mm), white to reddish white corolla and
white to purplish calyx. There were at least three (3) color
variations of S. pycnanthum’s calyx at Purwodadi BG, i.e.
white, purplish green and purple. Like other Syzygium
species as also ensured by
Belsham and Orlovich (2002),
Parnell (2003) and Viswanathan and Manikandan (2008),
the stamens of S. pycnanthum were numerous and densely
organized. The filaments were white on the tip and purplish
on the base. The fruit type was berry, globular, diameter
2.5-3.5 cm. The young fruit was green and later becomes
purplish green to light purple when ripe.
S. pycnanthum has hermaphrodite flower since it has
male and female organ on the same flower. The flower has
complete parts that are corolla, calyx, stamen and pistil;
therefore it is called a ‘perfect’ flower (Ashari 2002;
Flower and fruit development
The first phase of flower development is flower
induction, which is microscopic and takes place inside the
cells; whereas the next five phases are macroscopic so that
these phases can be viewed easily. The first phase involves
chemical reactions inside the cells that cause meristematic-
vegetative cells transform to meristematic-reproductive
cells. Rai et al. (2006), in their research on mangosteen’s
flower development, confirmed that the flower induction
phase had correlation with the changes of gibberellin and
sugar contents. This research was observing the last five
phases of flower development. The details of observation
results were showed in the next table (Table 1).
Based on recorded data, it was shown that the total
period needed to complete the whole process of fruit
formation was 80-89 days. As comparisons, Schmidt-Adam
et al. (1999) recognized six stages of flower development on
Metrosideros excelsa (Myrtaceae), it needed approximately
Num ber of rainy day
Phase III. Pre-anthesis
Phase VI. Fruit formation, fruit ripening and seed formation
Notes: line bars in picture represent 5 mm
Jamsari et al. (2007) proved that the flower development of
early bud, bud, flower blooming and fruit formation. The
average time for the whole process needed is 112 days.
Whereas study done by Rahayu et al. (2007) provided
evidence that Hoya lacunosa needed 8-11 weeks or 56-77
days. Another closer related species (Myrtaceae family),
namely Melaleuca cajuputi, needs 277 days to pass the
whole process of ripening fruit, starting from the flower
initiation (Baskorowati et al. 2008). Alas, the study on the
flower and fruit development of other Syzygium species by
other workers has not been found yet.
S. pycnanthum needs 26-31 days to pass the initiation
phase and the anthesis phase; to be specific; the anthesis
takes place for 1-2 days. Generally, the initiation and
anthesis processes of tropical and subtropical plants take
place in a very short time; however, the needed periods
were varied among different species (Ashari 2002). For
instance, Metrosideros excelsa (Myrtaceae) needs less
time, i.e. 6 days to go through the anthesis phase (Schmidt-
Adam et al. 1999). Greatly more times (roughly 8 months)
were needed by avocado (Persea americana Mill.) to go
past anthesis as observed by Salazar-García and Lovatt
(2002). Some species of Syzygium at Purwodadi BG were
also observed, they were S. jambos and S. creaghii. S.
jambos needed 54-73 days, whereas S. creaghii needed 82-
112 days to pass the flowering and fruiting formation
phases. The observation of other Syzygium collections have
still being carried out continuously.
The phase of flower blooming determines the
pollination process. At this time, the flower usually
produces fragrant odor that attract insects or other
pollinators to help the pollination process. Beside the
scented smell, some flowers also produce nectar to attract
the pollinators (Uji 1997). The percentage during flower
initiation to fruit ripening was presented in Figure 2.
Figure 2. Percentage of the period of flower and fruit
development’ phases of S. pycnanthum. A. Flower initiation
(28%), B. Pre-anthesis (4%), C. Anthesis (1%), D. Pollination and
fertilization (36%), E. Fruit formation, fruit ripening, and seed
Figure 2 describes the percentage of periods needed for
each phase of flower initiation and fruit development of S.
pycnanthum. It showed that among the periods needed for
flower to transform into fruit, the most time spent was for
pollination and fertilization (36%). This phase was
characterized by: the fall of corolla and stamen, the stigma
dried out and the swollen receptacle. This phase is very
important for producing fruit and seed successfully. Among
the flowers on the same inflorescence, only few of them
can develop and go through this phase. Some of them fall
off and did not develop to form fruits. This could be
assumed that the pollination and fertilization process was
not working properly. Gomes da Silva and Pinheiro (2009)
stated that not all flowers produced fruit during
reproductive process because of limiting factors occurred
during at each stage of the process. However S.
position of stigma is in the middle of the whorl (of
stamens), cause the pollination process easily happen.
Moreover, the same height of the anthers and the stigma
caused the pollen easily fall off on the stigma. In addition,
S. pycnanthum had numerous dense stamens; this made
higher changes of pollination possibly occurred especially
when pollinators perch on the flowers. The moves of the
pollinators assist to stick the pollen on to the stigma.
Pollination is a process of falling pollen on the stigma,
and fertilization is a process of the assembly of male
gamete (from pollen) and female gamete (inside the ovary).
The later process is influenced by internal and external
factors. The internal factors consist of the flower numbers,
the stigma and stamen position, the pollen maturity and the
stigma fertility. Pollen and stigma of S. pycnanthum mature
at the same time. The external factors include pollination
vectors, weather and climates. Rahman (1997) suggested
that beside those two factors, there was another factor
namely the compatibility of pollen and stigma. This factor
related to the genetic structure and composition of pollen
and stigma. Pollination and fertilization will only occur to
the similar species or to plants if they have compatible
genetic structures and compositions. Cross pollination is
also possible when some flowers mature at the same time.
S. pycnanthum blooming, flower releases
fragrant odor to the air so that the people around the plant
can smell the fragrant. According to Ashari (2002) the
aroma, the color and the flower shape were the attractive
parts of flower to draw the insects attention to visit the
flower. Some insects were recorded visiting the flowers of
honeybees, butterflies, bumble bees, black ants and others.
This research was only observing the visitors of S.
pycnanthum, while the real pollinator needed further
research and observation so that it can not be clearly stated
yet which one was the real pollinator or which one was
The last phase of flower development of S. pycnanthum
was characterized by the formation of young fruit; it
emerged from the developed receptacle. The increase of
fruit size and the change of fruit color (from green to
purplish green, and finally became purple) were visible
phenomenon. The other observable fact was the decrease of
common in the Syzygium species, i.e. the calyx trace still
can be seen on the fruit apex. The ripe fruit was globular,
purple, 2.5-3.5 cm in diameter and one to two seeded.
It has been noted that there were ten (10) stages of
flower and fruit development of Syzygium pycnanthum.
These stages were part of six (6) main phases of common
development of flower and fruit, apart from the first one
(was not observed), namely (1) flower induction, (2) flower
initiation, (3) pre-anthesis, (4) anthesis, (5) pollination and
fertilization and (6) fruit formation, fruit ripening and seed
formation. Syzygium pycnanthum required 80-89 days to go
through these latest five phases.
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