Authentication of Wax Apple (Syzygium samarangense (Blume) Merr. & L.M Perry) Delima and Citra Cultivars by Morphological and Molecular Approach

Syifara Chika, Tiara Dwi Meilina, Muhammad Ramdhani Arfan, Asri Febriana & Arnia Sari Mukaromah 2024. Genetic variation of wax apple (Syzygium samarangense (Blume) Merr. & L.M. Perry) cultivar using internal transcribed spacer 2 (ITS2). Floribunda 7(4): 153–165 — Wax apple (Syzygium samarangense (Blume) Merr. & L.M. Perry) is a tropical fruit, has diverse cultivars and classified as a non-climacteric fruit. The study objectives were to identify the genetic variation of the S. samarangense cultivars in the ITS2 DNA barcode region, analyze the phylogenetic relationships among S. samarangense cultivars and determine successfulness of ITS2 barcode to describe genetic variation of the S. samarangense cultivars from Demak Regency, Central Java, Indonesia. Furthermore, the stages in this study consisted of sampling, environmental parameters analysis, DNA isolation, DNA amplification, electrophoresis, DNA sequencing in the First Base Malaysia, analysis of DNA sequencing data, secondary structure prediction of ITS2, and reconstruction a phylogenetic tree using MEGA 11 and ITS2 database. The result shown appearance of few nucleotide variation among S. samarangense cultivars and there were nucleotides variations between S. samarangense and Syzygium aqueum in the ITS2 region. S. samarangense cultivar Citra Wonosari and cultivar Delima Wonosari had the identical secondary structure of ITS2. However, this was slightly different between S. samarangense cultivar Citra Botorejo secondary structure of ITS2 which consisted of only two loops in helix I and cultivar Citra Tempuran second loop in helix I which bigger than all samples. The phylogenetic tree described the closely relationship between S. samarangense Citra cultivars, and had separated S. samarangense cultivar Delima in the different clade. The genetic relationship of S. samarangense cultivars were more influenced by cultivar type rather than cultivated location. Therefore, ITS2 could be utilized for genetic variation analysis of S. samarangense cultivars.

The fruit known as wax apple, scientifically named Syzygium samarangense (Blume) Merr. & L.M. Perry, is a well-liked agricultural product originating from Demak Regency in the Central Java Province. When it is difficult to distinguish between different forms of an organism, using DNA barcoding to authenticate the identity of species based on their DNA is an important way. The psbA-trnH intergenic spacer is a commonly used molecular approach to analyse the genetic characteristics of plant species. This study investigated the psbA-trnH intergenic spacer profile of wax apple cultivars from Demak regency. The investigation revealed that the psbA-trnH intergenic spacer sequences of the S. samarangense cultivars, namely Madu Thailand and Madu Deli Hijau, had lengths of 535 and 492 base pairs, respectively. Both cultivars demonstrate a greater nucleotide composition of deoxyadenylic acid (A) and deoxythymidylic acid (T) in comparison to deoxycytidilic acid (C) and deoxyguanylic (G). The genetic distance between S. samarangense ‘Madu Thailand’ and ‘Madu Deli Hijau’ indicates a very tight relationship, with a value of 0.000. The psbA-trnH intergenic spacer proved to be insufficient in differentiating the S. samarangense cultivars from Demak regency, mostly because to its low capacity to discern between the wax apple cultivars. Keywords: Demak, psbA-trnH intergenic spacer, Syzygium samarangense, wax apple

Wax apple is one of the superior fruits of Demak, especially cultivars 'Citra', 'Delima' and ‘Madu Deli Hijau'. Research on the wax apple of the three cultivars is still limited. Therefore, research on the authentication of wax apple cultivars based on morphological characters and metabolite profiles present in one location is important to do. The aims of this study were to identify morphological characters and analyze metabolite profiles, to analyze relationship and to identify morphological characters and metabolite marker profiles in the authentication activities of three wax apples cultivars. Sampling was in Boyolali Village, Demak Regency. The stages of this research included morphological characterization of stem, leaf, fruit and seed organs, phylogeny analysis with MVSP, metabolite profile analysis using GC-MS, and determination of morphological characters and metabolite profiles with PCA. The results showed that there were morphological diversity and metabolite profile variations of the three cultivars. Relationship analysis based on morphological characters and metabolite profiles resulted in different grouping patterns. 'Madu Deli Hijau' and 'Citra' are closely related based on morphological characters and a combination of morphological characters and metabolite profiles. Morphological characters in the authentication of the 'Citra' (dark red exocarp color), 'Delima' (bright red exocarp color, smooth and flat fruit surface, jagged fruit shape), in 'Madu Deli Hijau' (elongated leaf shape and exocarp is green with a pink tinge). Authentication of probable marker metabolite profiles on 'Citra', 'Delima' and 'Madu Deli Hijau' wax apples of 10, 7 and 5 compounds.

Wax apple (Syzygium samarangense Merr. & Perry) has been a popular fruit crop in Taiwan because of its refreshing taste and attractive appearance. Pingtung County, accounting for 78% of the total planting area, is the major cultivation area. Regardless of the stable domestic and export market demand, the production area in Taiwan has decreased by almost 30% in the past decade, mainly due to labor shortage, high technical threshold, and production risk. Nevertheless, the cultivation area in central Taiwan has been increasing in recent years, especially in Nantou, Chiayi, and Yunlin Counties. The expansion of production regions facilitates year-round supply of wax apple fruits. By choosing suitable cultivars and forcing techniques in combination with adequate geographical and environmental conditions, a continuous supply chain for premium fruit has been established. Between October and December, market demand is fulfilled by fruits from Liukuei District in Kaohsiung City. Fruits from Pintung area satisfied the winter/spring market, from November to May. The cool temperatures in high altitude areas (600-1000 m a.s.l.) of Chiayi and Nantou favor the production of high quality fruits for niche markets from June to September. In addition, quality fruits of cultivars with consistent good fruit coloring and low cracking rates can be produced, from March to May, in Pingtung and, between June and September, in central Taiwan. Innovative production technologies and progressive breeding programs further ensure the sustainability of year-round wax apple production in Taiwan.

Wax apple (Syzygium samarangense (Blume) Merr. & L.M. Perry) is a tropical non-climacteric fruit and belongs to Myrtaceae. It has high diversity in cultivars, metabolite content, and its biological activities. In this comprehensive review, research findings had revealed that various metabolites found in the wax apple have biological activities. The said biological activities such as: antioxidant, immunomodulatory, antibacterial, anticancer, anti-glycation, anti-inflammation, anti-hypertriglyceridemic, anti-hyperglycemic, relaxant, and spasmolytic activities. Other potential use for the metabolites also includes the treatments for neurodegenerative abnormality, analgesic, and central nervous system (CNS) depression agent. Furthermore, wax apple physiological and phytochemical characteristics can be enhanced by girdling technique, hydrogen peroxide treatment, plant growth regulators treatment, and fruit bagging treatment. Meanwhile, postharvest technology of wax apple fruit utilizes nitric oxide treatment, oxalic acid treatment, cold treatment, and Aloe vera gel coating. Wax apple has also been evolved as an ointment, anti-acne cream, and nata de guava. However, environmental stress becomes a challenge in the wax apple plantation. Therefore, the development of molecular biology, chemistry, and postharvest technology will solve those challenges. This review concludes that wax apple (S. samarangense) is a tropical fruit that promises to support the nutritional values and human health.

Currently, there are limited documented reports on effects of horticultural practice such as shading, fruit thinning and the application of naphthalene acetic acid (NAA) on fruit growth, development, and quality of wax apple (Syzygium samarangense Merr. & Perry) in Taiwan. NAA and horticultural practices are important means used in fruit production throughout the world. These means regulate several physiological and biochemical aspects of growth, development, yield and quality of fruits. In this study, three experiments were conducted to improve the potential of wax apple fruits as follows; the first experiment evaluated the effect of naphthalene acetic acid (NAA) fruit quality of Indonesia wax apple cultivar, the treatments using 10 ppm NAA, 30 ppm NAA and without spray NAA as control. The second experiment evaluated the effect of fruit thinning plus bagging (brown paper bag and white paper bag) on fruit quality of ‘Red A’, ‘Red B’, ‘Pink’, and ‘Vietnam White’ wax apple cultivars. The third experiment tried to force flowering time by shading with black cover net. NAA was sprayed at the small bud and full blossom stage, fruit thinning was controlled to 6 fruits per cluster; bagging was performed about the implementation of 20 days after flowering and shading treatment at 80%, 40% and without shading (control). The physical and biochemical quality characteristics of the fruits were recorded. The result of the first experiment showed fruit length, fruit diameter, average fruit yield, and flesh thickness were highest at 30 ppm NAA treated branches compared to 10 ppm NAA treated and control branches. Fruit cracking decreased with increasing NAA concentrations. Lowest fruit cracking occurred in fruits treated with 30 ppm NAA. Number of seeds has no significant difference between treated and untreated fruits. Total soluble solids (TSS), pH, and vitamin C were also highest in 30 ppm NAA treated fruits and lowest in control fruits. Titratable acidity acid (TA) was decreased in treated fruits. In the second experiment, the result showed that fruit thinning and bagging affected the fruit yield and quality of the four wax apple cultivars. Fruit length, fruit diameter, average fruit yield, and flesh thickness were higher in treated branch than control branches. Fruit cracking decreased with bagging treatment. Lower fruit cracking occurred in fruits treated fruit thinning and bagging. Bagging was slightly affected on fruit color (on Pink cultivar). Total soluble solids (TSS) and pH were also higher in treated fruits compared with control fruits. Titratable acidity (TA) was decreased in treated fruits. From two experiments it can be concluded that fruit thinning plus bagging and spray of NAA 30 ppm showed better effects on fruit length, size and biochemical quality in wax apple fruits under field conditions. The third experiment didn’t get the results as we expected, in the future we need to do more study about the effect of shading on flowering time and combine with other methods.

Wax apple is one of the important fruit crops of Thailand. The major problems of wax apple production in Thailand are fruit flies and birds. Farmers have to bag the fruit after fruit set with a white plastic bag to prevent fruit flies, but the white plastic bag cannot protect the fruit from birds. Six wax apple trees, 15 years old, were selected for the experiment. The fruit of each tree was bagged with 10 bags each of white, yellow, green, blue, red and black plastic bags. A total of 360 bags were used. The quality of fruit was recorded after harvest. The results showed that the width, length, weight, volume of fruit, TSS, TA, and TSS/TA were different among different treatments. The mean weights of the fruit were 145.52, 142.62, 140.70, 139.30, 137.43 and 126.42 g in the white, red, yellow, green, blue and black bagged groups, respectively. The TSS were 9.96, 9.73, 9.55, 9.53, 9.38 and 9.38 °Brix in the white, yellow, red, blue, green and black bagged groups, respectively. In conclusion, we recommend that red and yellow plastic bags can be used for bagging wax apples while the black colour is not recommended.

The wax apple or jambu madu, is a non-climacteric tropical fruit from Myrtaceae family and widely cultivated in South East Asia. The limited availability of good quality seedlings of wax apple is the main problem to development of flourish it's market share in the current fruit industry. Therefore, in order to produce good quality planting materials, a study aimed at optimizing propagation and adventitious rooting technique and survivability of wax apple air layer was conducted. In this study, four different levels of Indole-3-Butyric Acid (IBA) concentration (0, 1000, 1500 and 2000 mg L-1) and three rooting media (sphagnum moss, vermicompost and garden soil) were applied after removal of bark (phloem) on the shoot to determine the effect on rooting and survivability of the wax apple air layer under field conditions. The results showed that the wax apple shoots treated with 2000 mg L-1 IBA produced the significantly higher number of roots, increased length of root, diameter of branch, length of branch, number of leaf and leaf area of air layers. In addition, the highest chlorophyll content and stomatal aperture were recorded in 2000 mg L-1 IBA treatment compared to other treatments including control. Vermicompost medium was better than garden soil and sphagnum moss in respect of rooting and survivability of air layers. The results showed that the combination of 2000 mg L-1 IBA and vermicompost as rooting media give the best combination to root initiation, root number, root length and survival rate (100%) of wax apple air layers. From this study, it can be concluded that 2000 mg L-1 IBA and vermicompost treatment enhance the root initiation, early establishment and survivability of wax apple air layered under field conditions.

The objective of this study was to find a chemical compound to substitute fenitrothion as the flower advancing agent of wax apple trees. Fenitrothion, classified as an organophosphate pesticide, has been used to advance blooming for some time. Due to its negative side effects on farmers’ health and ecological concern, searching for a new agent as a replacement has become necessary. Various reports indicated that KH2PO4 has been effective in the post-harvest defoliation, and played a role in flower initiation. Thus experiment has been designed to test the possibility of replacing fenitrothion with KH2PO4 in the advancing flower of wax-apple. By dipping a wax-apple branch in KH2PO4 solution in stem-feeding system, leaves showed signs of abscission and water soaking. The tendency was similar to those treated with ethrel or fenitrothion. Samples treated with KH2PO4, ethrel and fenitrothion were analyzed for their potassium and phosphate contents. KH2PO4 treated had the highest phosphate concentration. Ethylene production was also proportional to the concentration of KH2PO4. Ethylene peaked on the third day after the treatment of 100 mM KH2PO4 and abscission started on the seventh day. Leaf disc experiments were conducted to determine the ethylene production and CO2 release. Wax-apple leaf-dises treated with KH2PO4 or NaH2PO4 showed that the rate of ethylene release was proportional to the concentration of either compound, though KH2PO4 treated was superior. There was no response in KCl treated disc. This result demonstrated that phosphate was the major factor for inducing ethylene production. Mannitol solution was used as a buffer and no effect on the KH2PO4-induced ethylene production. The leaf discs of releasing rate of ethylene is influenced by light intensity. Effect the ethylene production apparently under high light intensity, as the intensity reduces the releasing rate of ethylene to reduce. Adding inhibitors AVG, CHI, 1-MCP separately to KH2PO4-treated leaf discs, ethylene production was significantly reduced by AVG and CHI, and not affected by 1-MCP. But inhibition took effect when AVG or CHI was added to the1-MCP treated sample. This seemed to explain that the biosynthesis of ethylene induced by KH2PO4 was similar to the general pathway of ethylene synthesis in the plant. In field experiments both fenitrothion and KH2PO4 caused a change in carbohydrate concentration and a faster flowering was induced by KH2PO4. After evocation activated by fenitrothion or KH2PO4, chlorophyll and chlorophyll flurometric parameter (Fv/Fm) increased gradually. Wax-apple evocation often limited by climatic conditions but the post-harvest fruit qualities were not affected by either chemical treatment. According to the results of this study, it shows that KH2PO4 can be a wax-apple flower advancing agent instead of fenitrothion in the field application.

Citrus is a very important fruit crop in Taiwan with an acreage of more than 32,000 ha, however, the threat from the oriental fruit fly (Bactrocera dorsalis Hendel, OFF) is a constant problem. Current OFF control program started in 1959 for the purpose of protecting the citrus for export, and control of OFF has been on the priority list. Following the success of area-wide control of OFF in sugar apple (in Taitung) and wax apple (in Juan-Nan), practical test on citrus becomes urgent. Da-Lin Township of Chia-Yi County was selected because citrus is the only fruit crop grown in this area. With the corporation of growers from Da-Lin, an area-wide OFF control program was launched in 2005, which included measures such as geographic and agricultural information gathering. OFF population monitoring, male annihilation by methyl eugenol bait and protein food bait to kill and lure female OFF. The 400 ha test area covering 120 ha citrus orchards started the control program since early June of 2005, and the OFF population was greatly reduced to less than one fly per trap per day. No hot spots were found due to alternative hosts of OFF was rarely existed in this area. The citrus production in Da-Lin was not subjected to bagging as it was done to the the wax apple or sugar apple. As such, the OFF damage rate was assessed directly. By sampling the citrus fruits from three orchards, 0.35% damage rate was obtained. Another benefit of this program was no insecticide spray needed. Reduction of OFF damage minimized the cost of insecticide spray and residual problem, which also improved the quality of citrus fruits and the environment in which farmers are routinely working. For two consecutive years, the saving of insecticide spray was estimated at 1.4 million NT dollars (US$ 44,343) per year. It is also observed that economic motivation and farmer education were essential to a successful area-wide control program. The small acreage model in citrus is of vital importance because there are a number of similar production areas like Da-Lin in Taiwan, and field demonstration on area-wide OFF control to other citrus growers will be initiated in the near future.

Wax apple (Syzygiumsamarangense) fruit extract ameliorates endothelial dysfunction and liver damage in high cholesterol diet-fed rats

Wax apple (Syzygium samarangense) is an important tropical fruit crop in Southeast Asia. The rapid cottony softening that occurs after harvest significantly influences the nutrition, flavour and market value of the fruit. Nitric oxide (NO) fumigation has been used to delay the cottony softening process in wax apple; however, the underlying molecular mechanisms at the gene regulation level are poorly understood. In this study, we first sequenced and de novo assembled the wax apple fruit transcriptome using the Illumina Hiseq2000 platform. Meanwhile, we compared the gene expression profiles between NO treatment and control wax apples at different postharvest storage periods using digital gene expression (DGE). This study developed transcriptome data resources for wax apple fruit and provided a foundation for understanding the molecular mechanisms underlying NO-induced cottony softening delay. RNA-Seq generated 5.9 G raw data, which were then de novo assembled into 54,536 unigenes with an N50 length of 1724 bp. 21,433 Unigenes were annotated by the nr database and 3044 were successfully annotated by all databases. The dynamic analysis of the gene expression patterns suggested that NO-induced delays of cottony softening occur in wax apple via the regulation of cell wall degradation, carbohydrate metabolism, oxidation–reduction and plant hormone signal transduction pathways. These results provide a reference for the study of complicated metabolism in non-model perennial species.

Used Artocarpus heterophyllus,Syzygium samarangense,Garcinia mangostana and Annona squamosa as raw materials,the dietary fiber was prepared by chemical binding enzyme method.And used SEM,IR and chemical analysis to study the structural characterization,monosaccharide composition and physical and chemical properties of the prepared dietary fiber. The results showed that:the content of dietary fiber in Annona squamosa was higher,reached(74.31±0.07) g/100 g. The contents of cellulose,hemicellulose and lignin in dietary fiber of four tropical fruits were different. The typical characteristics of polysaccharide in dietary fiber of four tropical fruits were found by infrared spectrum scanning. GC analysis of glyconitrile acetylated derivatives showed that the dietary fiber of four tropical fruits contained rhamnose,arabinose,xylose,glucose,galactose and mannose,and the molar ratio was 1:4.6:6.8:9.4:5.6:3.4(Artocarpus heterophyllus),1:5.9:5.8:4.9:3.9:3.6(Syzygium samarangense),1:4.2:6.1:6.1:2.6:3.1(Garcinia mangostana),5.2:18.9:1:53.4:7.1:7.1(Annona squamosa). Annona squamosa dietary fiber had higher swelling power and cholesterol adsorption(pH2),respectively(21.28±1.15) mL/g,(10.72±0.17) mg/g(pH2),which were significantly higher than those of the other three tropical fruits(P<0.05). The water retention and cholesterol adsorption(pH7)of the dietary fiber of Syzygium samarangense was high,which were(21.90±0.55) g/g,(11.25±0.37) mg/g. Garcinia mangostana dietary fiber had a high oil retention rate of(7.79±0.28) g/g.Scanning electron microscopy morphological characteristics showed that the apparent morphology of dietary fiber of four tropical fruits was significantly different.

Wax apple (Syzygium samarangense) is a tropical fruit with attractive appearance and thirst-relieving properties, offering a unique apple-like crispness, watery-sweet, low-acid taste and the aroma of roses. Compared to whole fruit, fresh-cut fruits are more perishable due to high respiration, ethylene production, and membrane degradation, thus reducing fruit usage. This paper reports the effect of storage period and cut sizes on quality of fresh-cut wax apples. Fresh wax apple fruits were prepared according to the treatments: whole, halved (1/2), quartered (1/4), and wedged (1/8) and stored in a domestic refrigerator (4°C), in a clear plastic container (ca. 260-280 g). Results showed that there was a significant interaction between storage period and cut sizes on weight loss. Samples stored as whole lost the least amount of water. Weight loss for all cut sizes were less than 1.6%. The firmness of wax apple on day 9 of storage was significantly lower than their initial firmness. The whole fruit was found to be softer than the freshly cut samples. Total soluble solids content decreased with the time of storage, reduced from 7.6 to 6.2 °Brix as the storage period extended from day 0 to day 9 irrespective of cutting sizes. Titratable acidity increased significantly from day 0 to day 3 of storage for halved, quartered and wedged fruit. The concentration of ascorbic acid decreased significantly throughout the period of storage. Overall, results clearly showed that storage period markedly affected the physico-chemical properties of wax apples regardless of their cut sizes but not to the extent that the quality of fresh-cut wax apple was reduced.

Rose apple cv. Dalhari is a local fruit grown in Berbah District, Special Region of Yogyakarta. This fruit perishable easily loses its water content and is attacked by microbes. This research aimed to determine the best combination between alginate and betel essential oil to inhibit the growth of microbes and maintain quality of rose apple cv. Dalhari. Alginate and betel essential oil treatments were used at three concentration levels, alone and in combinations, respectively of 2%, 2.5%, 3% and 0%, 0.1%, 0.2%. The results showed that combination treatment of 2.5% alginate and 0.1% betel essential oil was the most effective to maintain the fruit quality. The sole addition of betel essential oil was not able to inhibit microbial growth. Furthermore, combination of alginate based edible coating and betel essential oil was able to maintain the quality of rose apple cv. Dalhari up to nine days.