African Journal of Agricultural Research Vol. 6(15), pp. 3623-3630, 4 August, 2011
Available online at http://www.academicjournals.org/AJAR
ISSN 1991-637X ©2011 Academic Journals
Full Length Research Paper
characteristics of cultivars of Syzygium samarangense
Photosynthetic yield, fruit ripening and quality
*, A. B. M. Sharif Hossain
, Rosna Mat Taha
and K. M. Moneruzzaman
Adel. M. Al-Saif
Biotechnology Division, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala
Department of Plant Production, College of Food and Agricultural Sciences, King Saud University, P. O. Box
2460, Riyadh 11451, Saudi Arabia.
Accepted 15 June, 2011
This study was carried out to evaluate the photosynthetic yield, color development and quality
characteristics of three cultivars of Syzygium samarangense at commercial farm of Banting, Selangor
and functional food laboratories, University of Malaya, Kuala Lumpur. Various physiological and
biochemical parameters were studied during two seasons of fruit growth from October, 2009 to August,
2010 with the ‘Giant Green’, ‘Masam manis Pink’ and ‘Jambu madu Red’ cultivars of S. samarangense.
Results showed that the highest chlorophyll content, maximal and variable fluorescence (Fm and Fv) in
mature leaves and photosynthetic yield (Fv/Fm) were found in ‘Jambu madu Red’ cultivar. Furthermore,
this cultivar that had the medium time for fruit development also produced the highest amount of Juice
content (ml/100 g). The highest, lower fluorescence (F0) in mature leaves, maximal fluorescence (Fm)
and variable fluorescence (Fv) in new flush, the earliest peel color and the fruit maturity were observed
in ‘Masam manis pink’ cultivar. The highest, lower fluorescence F0 in new flush and chlorophyll a,
chlorophyll b and total chlorophyll were recorded in fruit of ‘Giant Green’ cultivar. Also, some other
quality parameter like peel, pulp, biomass and juice color, aromatic flavor, texture and taste were taken
into account to compare the quality in the cultivars of S. samarangense. This study also showed that
the photosynthetic yield had a strong correlation with the fruit biomass among the three cultivars. In
conclusion, Jambu madu Red’ and ‘Masam manis pink’ ‘cultivars are comparatively better than ‘Giant
Green’ cultivar if cultivated under South Asian conditions.
Key words: Syzygium samarangense
, photosynthetic yield, ripening, quality, cultivars.
The wax jambu (Syzygium samarangense) is a non-
climacteric tropical fruit, others names are wax apple,
rose apple and java apple. The color of the fruit is usually
pink, light-red, red, green, sometimes greenish-white, or
cream-colored (Morton, 1987). The species presumably
originated in Malaysia and other South-East Asian
countries. It is widely cultivated and grown throughout
*Corresponding author. E-mail: firstname.lastname@example.org. Tel: 03-
79674372. Fax: 03-79674178.
F0, Fluorescence; Fm, maximal fluorescence;
variable fluorescence; FDP, fruit developmental period;
completely randomized design; LSD, least significant
Malaysia and in neighboring countries such Thailand,
Indonesia and Taiwan. Currently in Malaysia it is
cultivated mainly as smallholdings areas ranging from 1
to 5 ha with its hectarage estimated at about 2000 ha in
2005 (Shu et al., 2006). Syzygium is a genus of flowering
plants that belongs to the family, Myrtaceae. The genus
comprises about 1100 species (Little et al., 1989). High
levels of diversity occur from Malaysia to northeastern
Australia, where many species are very poorly known
and many more have not been described taxonomically
(Morton, 1987). Some of the edible species of Syzygium
are planted throughout the tropics worldwide. In
Malaysia, there are about three species which bear
edible fruits, namely the water apple (Syzygium aquem),
Malay apple (Syzygium malaccense) and wax jambu (S.
). The pink, red and green cultivars of wax
jambu are popular in Malaysia and others South East
3624 Afr. J. Agric. Res.
Asian countries. The fruit is rounder and more oblong in
shape, also having a drier flesh than the wax jambu. Wax
jambu commonly flower early or late in the dry season;
the flowers appear to be self-compatible and the fruit
ripens 40 to 50 days after anthesis.
Fruit is a berry, pear shaped, broadly pyriform, crowned
by the fleshy calyx with incurved lobes, 3.5-5.5 × 4.5-5.5
cm, light red to white; fruit flesh is white spongy, juicy,
aromatic, sweet-sour in taste. Seeds 0 to 2, mostly
suppressed globose up to 8 mm in diameter (Morton,
1987). The waxy fruit is pear shaped and the color of the
fruit is usually pink, light-red, red, sometimes green or
cream-colored (Morton, 1987). The size, shape and color
of fruit are usually distinct characteristics for different
cultivars in the same species (Galan, 1989). Only few
cultivars of wax apple are available, which are exotic and
perpetuated through vegetative methods of propagation
(Morton, 1987). Measurement of the chlorophyll a
fluorescence is a quick, precise and non-destructive
technique, widely used in investigating damage/repair
caused in the photosynthesis plant system by various
types of stresses (Govindjee, 1995). The different cultivar
produces fruits varying from pink to deep red, depending
on environmental and cultural conditions. Fruit color is
influenced by many factors, such as light, temperature,
position on the tree, growing stage, and leaf: fruit ratio
(Shu et al., 2001). It has been reported that different
cultivars of wax jambu are different in their morphological
and physiological characteristics depending on the
genetic behavior, location and climatic conditions, yet this
has to be documented. Currently very little information is
available in the literature on photosynthetic yield, color
development and quality characteristics of three cultivars
of S.samarangense. Hence, this study is aimed to
evaluate the photosynthetic character, color development
and quality as well as the physiological and biochemical
characteristics of the three cultivars of S. samarangense.
It is also useful to assess the quality and the relationship
between the photosynthetic yield and the fruit biomass of
the three cultivars under South East Asian region.
MATERIALS AND METHODS
The present study was carried out during the year of 2009 to 2010
to point out the photosynthetic characteristics, color development
and quality compare of three cultivars of wax jambu
(S.samarangense) namely ‘Giant Green’, ‘Masam manis Pink’ and
‘Jambu madu Red’ available at commercial farm of Banting,
Selangor, Malaysia. Five trees of each cultivar (about 13 years old),
were selected from a commercial farm in Banting, 2°
30 N, 112° 30
E and 1°28 N, 111° 20 E at an elevation of about 45 m from sea
level. The area under study has a hot and humid tropical climate.
The soil in orchard is peat with a mean pH of around 4.6 (Ismail et
al., 1995). The experimental trees received similar horticultural
photosynthetic characteristics, fruit development and pigmentation
characteristics of each cultivar as mentioned below. Chlorophyll
content in leaves was determined using a Minolta SPAD meter.
SPAD meter were calibrated before taking the readings. A single
leaf was attached with the SPAD meter for chlorophyll readings.
The SPAD value of the leaves was determined at the immediately
after anthesis. Ten readings were taking per treatment. Chlorophyll
fluorescence was measured by Hansatech Plant Efficiency
Analyzer. It was represented by lower F0, Fm and Fv.
Photosynthetic yield (Fv/Fm) also evaluated at 28°C and time rage
was 10 µs
. Fruit development of each cultivar was monitored
weekly. Flowers from each cultivar were tagged when available
from 15 February to 17 May 2000. In total, 150 randomly chosen,
open flowers were tagged (50 ‘Giant Green, 50 ‘Masam manis
Pink’, and 50 ‘Jambu madu Red’). The number of flowers tagged
ranged between 1 and 10 for each cultivar on a particular date. On
each tag, the date and flower position (1, 2, or 3°) was recorded.
Then, as fruit approached horticultural maturity, they were observed
every day and the dates on which they reached full maturity (that is,
full color) were recorded.
This data was used to calculate fruit developmental period (FDP).
Fruit were harvested after reaching full maturity. The surface color
of each tagged fruit was determined at three different points of the
fruit using a standard color chart (Minolta, Osaka, Japan) and
expressed as percentage of color cover. The chlorophyll content of
both leaf and fruit was determined by methods described in Hendry
and Price (1993). The peel, pulp, juice and biomass color was
determined using a standard color chart (Minolta, Osaka, Japan).
content of the fruit juice was determined by using a Cardy
Potassium meter. After extraction of fruit juice, 3 to 5 drops of fruit
juice were placed on to the calibration sensor pad of Cardy
Potassium Meter, Model-2400, USA. The reading in ppm was taken
from the display pad after it stabilized of 20 s. Firmness was
measured by deformation, under constant load of 400 g, with a
penetrometer (Durapat et al., 1986). A sensorial analysis of taste
and aromatic flavor was carried out at the laboratory among the
ripen fruits of the three cultivars. We have employed a triangle test
in which the tasters were asked to state whether one of the
samples differs from the other two presented. The experimental
design was Completely Randomized Design (CRD) comprised of
three cultivars with ten independent observations. Only quantitative
data were analyzed statistically using Fisher’s analysis of variance
techniques. One way ANOVA was applied to evaluate the
significant difference in the parameters studied within the different
cultivars. Least significant difference (Fisher’s protected LSD) was
calculated, following significant F-test (p=0.05).
RESULTS AND DISCUSSION
Leaf chlorophyll content
Plant structure and chlorophyll content strongly affect
rates of photosynthesis (Eitel et al., 2009). The
Chlorophyll a and b content of the new flush and mature
leaves was determined using a Minolta SPAD meter. The
results showed that the chlorophyll content in mature
leaves were not statistically significant among the
cultivars (Figure 1). In new leaves chlorophyll content
(SPAD value) also did not varied significantly among the
three cultivars of S. samarangense. The range of Chl
values was comparable to those shown in other studies
that examined the Chl
of broadleaf specie (Richardson
et al., 2002).
Potassium content in leaf
Potassium (K) increases the photosynthetic rates of crop
Al-Saif et al. 3625
Chlorophyll content in new and mature leaves of three cultivars of S. samarangense.
Potassium content in new flush of different cultivars of Syzygium
assimilation rate and facilitating carbon
movement (Sangakkara et al., 2000). The high
concentration of K
is thought to be essential for normal
protein synthesis. The physiological role of K during the
fruit formation, fruit setting and maturation periods is
mainly expressed in carbohydrate metabolism and
translocation of metabolites from leaves and other
vegetative organs to developing bolls. Pettigrew (1999)
stated that the elevated carbohydrate concentrations
remaining in source tissue, such as leaves, appear to be
part of the overall effect of K deficiency in reducing the
amount of photosynthate available for reproductive sinks
and thereby producing changes in yield and quality seen
in cotton. Notable improvements in fruit yield and quality
resulting from K input were reported by Gormus (2002),
Aneela et al. (2003), Pervez et al. (2004) and Pettigrew et
al. (2005). These may be reflected in distinct changes in
seed weight and quality. Cultivars of S. samarangense
produced significant differences in the case of K
in leaves (Figure 2). Results showed that the highest K
content of leaves (495 ppm) was recorded in ‘Jambu
madu Red’ cultivar followed by ‘Giant Green’ and ‘Masam
manis Pink’ cultivars with a potassium content of 477 and
463 ppm. The potassium content in the leaves of Wax
jambu cultivars might be genetically regulated. Level of
potassium was considered higher, when most plants on
potassium levels were in the range of 100 to +400 ppm.
In agriculture, some cultivars are more efficient at K
uptake due to genetic variations, and often these plants
have increased disease resistance (Datnoff, 2007).
Potassium has also been implicated to have a role in the
thickening of cell walls (Datnoff, 2007).
Chlorophyll fluorescence of new and mature leaf
The chlorophyll fluorescence has become one of the
most powerful and widely used techniques available to
plant physiologist and ecophysiologist. Chlorophyll
fluorescence gives information about the state of photo
system II. Chlorophyll fluorescence varied at different
cultivar and age of leaves (Table 1). The chlorophyll
3626 Afr. J. Agric. Res.
Chlorophyll fluorescence of new (NL) and mature leaves (ML) and total chlorophyll of three cultivars of S. samarangense.
‘Masam manis Pink’
‘Jambu madu Red’
Means (±S.E) within the same column followed by the same letter, do not differ significantly according to LSD test at ά=0.01 ns, non-significant
* Significant at 0.05 levels, ** Significant at 0.01 levels FO: lower fluorescence, Fm: maximum fluorescence, Fv: variable fluorescence.
fluorescence intensity was found fluctuated in all
cultivars. The highest (3890) Fm in mature leaves was
recorded in ‘Jambu madu Red’ followed by ‘Masam
manis Pink’ with a value of 3664, whilst, ‘Giant Green’
Cultivar produced the lowest (3446) Fm value. The
highest (922) lower fluorescence was recorded in
‘Masam manis Pink’ cultivar followed by ‘Jambu madu
Red’ and ‘Giant Green’ cultivar with a value of 866 and
865. Fv was highest in ‘Jambu madu Red’ cultivar
followed by ‘Giant Green’ and ‘Masam manis Pink’
cultivars (Table 1). In case of new flush, ‘Masam manis
pink’ cultivar had the highest Fm and Fv compare to the
‘Jambu madu red’ and ‘Giant Green’ cultivars. New flush
of ‘Giant Green’ cultivar produced the maximum lower F0
than ‘Masam manis Pink’ and ‘Jambu madu Red’
cultivars (Table 1), although their differences were not
fluorescence was attributed to difference in stomata
density. In a comparative investigation of ginkgo trees
across a climatic gradient in China, it was found that
ginkgo sun leaves possess a higher stomata density than
shade leaves (Sun et al., 2003). Also in beech, a tree that
exhibits the strongest high irradiance adaptation
response of its leaves and chloroplasts, the stomata
density of sun leaves amounts to ca. 210 stomata mm−2
leaf area as compared to only 144 in shade leaves
(Lichtenthaler et al., 2004). A higher stomata
conductance, together with a higher stomata density,
seems to be a typical characteristic of sun leaves and
one prerequisite for their higher PN rates (Boardman,
1977; Lichtenthaler et al., 2004)
Photosynthetic or quantum yield
Cultivars of S. samarangense had a significant effect on
photosynthetic yield or optimum quantum yield. ‘Jambu
madu Red’ and ‘Masam manis Pink’ cultivar yielded
significant difference from ‘Giant Green’ cultivar on
photosynthetic yield in new flash. Results showed that
highest (0.78) photosynthetic yield (Fv/Fm) in new flush
was in ‘Masam manis Pink’ cultivar followed by ‘Jambu
madu Red’ cultivar with a value of (0.77), whereas, ‘Giant
Green’ had the least (0.73) photosynthetic yield (Figure
3). Photosynthetic yield in mature leaves was also varied
significantly among the cultivars. As it is shown in Figure
3b, the highest (0.80) photosynthetic yield is observed in
‘Jambu madu Red’ cultivar followed by ‘Giant Green’
cultivar with a value of (0.79), whereas, the least (0.72)
photosynthetic yield was in ‘Masam manis Pink’ cultivar.
The differences among the cultivar may be genetically
makeup. Values of quantum yield of this work were
similar with those reported by Gulmira et al. (2007).
Total chlorophyll content
It is well documented in the literature that during ripening,
the skin of fruits changes from green to a different
brighter color. The most obvious change which take place
is the degradation of chlorophyll and is accompanied by
the synthesis of other pigments usually either
anthocyanin or carotenods. In this study the chlorophyll in
the peel of the fruits was measured at the fully ripening
stage. It was observed that the chlorophyll loss gradually
took place at color turning stage of the fruits. This results
reported that ‘Giant Green’ cultivar showed a significant
difference from ‘Jambu madu Red’ and ‘Masam manis
Pink’ cultivars. The highest (3.43 mg/l) chlorophyll
content in fruit peel was recorded in ‘Giant Green’ cultivar
followed by ‘Jambu madu Red’ cultivar with a chlorophyll
content of 1.33 mg/l, whilst the lowest chlorophyll content
(0.31 mg/l) was recorded in ‘Masam manis Pink’ Cultivar
Fruit ripening after anthesis
The fruit cultivars have a different number of days from
bloom to maturity (Westwood, 1978). It was reported that
the FDP for ‘McIntosh’ apple ranges from 125 to 145
days, while the FDP for ‘Golden Delicious’ apple ranges
from 140 to 160 days. the variation of the fruit in FDP,
also depends on the air temperatures. Westwood (1978)
also reported that Pears, apples and peaches grown at
relatively high temperatures during cell division (the
Al-Saif et al. 3627
Photosynthetic yield: (A) new flush and (B) Mature leaves of
three cultivars of Syzygium samarangense.
first 4 to 8 weeks after bloom, depending on species)
mature in fewer days than those grown at lower post-
bloom temperatures. The fruit developmental period after
anthesis varied significantly with different cultivars of S.
. Results showed that ‘Masam manis pink’
cultivar had the earliest fruit maturity approximately 38
days after anthesis followed by ‘Jambu madu Red’
cultivar with nearly 45 days (Figure 4). On the other hand,
‘Giant Green’ cultivar had late maturity. It takes longer
period of about 50 days after anthesis. Our findings
supported by the results of Morton (1987) who reported
that the average period from anthesis to berry maturity is
about 35 to 50 days in cultivars of wax jambu (Figure 4).
Peel, pulp and Juice color
One of the most conspicuous characteristics to
consumers of Wax jambu is the external color that is also
considered as an important varietal character. Fruit peel,
pulp and juice color are important not only for consumer
acceptability but also in association with aroma, flavor
and health benefits (Burger et al., 2006). Variability with
respect to fruit peel, pulp and juice color also recorded.
‘Giant Green’ cultivar had light green to green peel color,
‘Masam manis Pink’ cultivar had pink to crimson and the
‘Jambu madu Pink’ cultivar had light red to dark red peel
Table 2. Cultivars of S. samarangense produced different
color of fruit pulp. Greenish white pulp color was
observed in ‘Giant Green’ cultivar and ‘Jambu madu Red’
cultivars, whereas, pinkish white and reddish white pulp
was recorded in ‘Masam manis Pink’ (Table 2). These
variations are due to the genetic characters. The fruits
peel and the juice color is a genetic character for each
cultivar, species and variety. It was observed that ‘Giant
Green’ cultivar had green color juice. Light pink and light
red color juice were observed in ‘Masam manis pink’ and
‘Jambu madu Red’ cultivars. Our results confirmed by the
findings of Kumar et al. (1998) who reported that the
color of the fruits varies depending on the cultivars and it
is also influenced by the growing conditions and the
Volume of fruit juice and biomass color
Fruit juice is an important character in fruit processing
industry. The juice quality characteristics vary with
cultivar, fertilization, frequency of irrigation, date of
harvest, age of tree, tree spacing, position of fruit tree,
climactic condition and the places of growing. There were
significant variations in juice content of different cultivars.
The highest amount of juice (76.33 ml) was recorded in
‘Jambu madu Red’ cultivar, followed by ‘Masam manis
Pink’ with a juice content of 68 ml, whereas, ‘Giant color.
The data observed for fruit pulp color are shown in
3628 Afr. J. Agric. Res.
Photograph showing color development of different cultivars of Syzygium
Fruit characteristics of cultivars of S. samarangense during two seasons in 2009 and 2010. All the data represent in the table were
pooled for two years.
Name of cultivars
‘Masam manis Pink’
‘Jambu madu Red’
Means (±S.E) within the same column followed by the same letter, do not differ significantly according to LSD test at ά=0.01 ns, non-significant *
Significant at 0.05 levels, ** Significant at 0.01 levels.
Green’ cultivar produced the least (44 ml) amount of fruit
juice. From Table 2, it is revealed that the fruit biomass
color also depend on the cultivars. ‘Giant Green’ cultivar
had green fresh biomass, whereas, ‘Masam manis Pink’
and ‘Jambu madu Red’ had the pink and red biomass.
Firmness, aromatic flavor and taste
A great importance is given to study the textural
properties and aroma composition the fruits for varietal
characterization and quality assessment. ‘Giant Green’
cultivar had the highest aromatic flavor, whereas, ‘Masam
manis Pink’ and ‘Jambu madu Red’ cultivars had the
least aromatic flavor. In case of fruit texture, ‘Giant
Green’ cultivar had crispy in nature, while, ‘Masam manis
pink’ and ‘Jambu madu Red’ were soft and spongy (Table
2), Cultivar has an important role in determining the taste,
quality, yield and nutrient composition of fruits. Fruit taste
is mainly determined by the concentration and the type of
soluble solids and organic acids (Dirlewanger et al.,
1999). From our evaluation, ‘Jambu madu Red’ cultivar
had a relatively sweet taste and ‘Masam manis Pink’
cultivar had sweet-sour taste. On the other hand, ‘Giant
Green’ cultivar had sweet taste but it bears also a nice
aromatic flavor and a crispy fruit flesh. These results are
supported with the findings of Byrne (2002), who reported
that fruit taste varies with the cultivars.
Accumulation of dry matter content in plants depends on
photosynthetic yield or optimum quantum yield. Results
showed that photosynthetic yield had a strong correlation
Al-Saif et al. 3629
Correlation between photosynthetic yield and dry biomass of three
cultivars of Syzygium samarangense.
=0.96) with the fruit biomass among the cultivars of
wax jambu. Highest photosynthetic yield and fruit
biomass observed in ‘Jambu madu Red’ cultivar followed
by ‘Giant Green’ cultivar, whilst ‘Masam manis Pink’
cultivar had the least photosynthetic yields and dry fruit
biomass (Figure 5). The observations recorded in the
present investigation suggested that the different cultivars
varied markedly with respect to photosynthetic yield, fruit
ripening and quality characteristics. These varieties
appeared to be due to their genetic differences. From our
observation, it can be summarized that ‘Jambu madu
Red’ and ‘Masam manis Pink’ cultivars are comparatively
better than green cultivar. Finally, it can be recommended
that ‘Jambu madu Red’ cultivar is the best cultivars for
cultivation of South Asian regions for better market value,
yield and quality.
This research was supported by grant from University of
Malaya, Kuala Lumpur, 50603, Malaysia (Project
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