Christina Yong

Universiti Putra Malaysia | UPM · Department of Biology

Silver-leaved Zingiber group (Zingiberaceae) previously known only from Borneo was now appended with a new species from Taman Negeri Rompin, Pahang, Peninsular Malaysia — marking the first record of this group outside the Borneo island. The new species, Zingiber zulkifliana Tan, Besi & Go was described, illustrated, and compared to its closest rela...

Among cereal crops, rice (Oryza sativa L.) is the most susceptible to salinity. Due to emerging salinity impacts on food security, different strategies have been implemented including developing salt tolerant varieties. Therefore, this study was conducted to produce salt tolerant lines of ‘MARDI Siraj 297’ through in vitro callus selection, enhance...

Drought is a serious limiting factor to rice (Oryza sativa L.) production in Malaysia, and becoming a more significant issue with respect to the global climate change. This study selected 15 widely cultivated Malaysian indica rice genotypes whose drought tolerance level is still unknown. The study aimed to determine the changes in some biochemical...

Monitoring the impact of anthropogenic and naturogenic threats on orchid community through diversity, taxonomy and conservation studies is necessary. Reintroduction of these species to their natural habitat associates with their resilience, selection of suitable trees and sites for regeneration and restoration efforts, drives the conservation initi...

Seventy-two morphological characters and three ecological characteristics were measured to assess variation and phylogenetic relationships among twelve species and three infraspecific taxa of the genus Spathoglottis from Peninsular Malaysia and Borneo. The morphological analyses divided Spathoglottis into two main groups based on the colours of the...

The Malayan tapir (Tapirus indicus) is listed as Endangered on the IUCN Red List due to multiple threats such as habitat loss and human disturbance that have led to its population decline. This decline increases the risk of inbreeding, which could result in the reduction of genome-wide genetic variation and negatively affect the gene responsible fo...

As an attempt to examine the causes of forest disturbance and degradation of the orchid community, a comparative study on diversity and ecology in eight undisturbed and ten disturbed forests in Peninsular Malaysia was conducted that varied in areas, elevations, vegetation types, and disturbance regimes. Density and individual-based rarefaction curv...

The Malayan tapir (Tapirus indicus) is an endangered species endemic to Southeast Asia. Previous research have used maternally inherited, mitochondrial DNA genetic markers to investigate the population genetics of the species but not the biparentally inherited, nuclear genetic markers. However, the increasing pressure of habitat fragmentation and r...

Roselle (Hibiscus sabdariffa L.) is recognized for its phytochemical compounds such as anthocyanins, which possess pharmacological potentials in the treatments of hypertension, diabetes, cancer, hyperlipidaemia and hyperglycaemia. The calyx is the most commercially valuable part of the roselle and usually harvested at maturation. However, genetic s...

Callogenesis and embryogenesis are integral parts of many tissue culture procedures for genetic manipulation in rice. However, the efficiency of both processes is largely dependent on the media constituent especially the plant growth regulators (PGRs) due to the genotype-dependent nature of in vitro culture protocols. Therefore, this study investig...

Abstract: Callogenesis and embryogenesis are integral parts of many tissue culture procedures for genetic manipulation in rice. However, the efficiency of both processes is largely dependent on the media constituent especially the plant growth regulators (PGRs) due to the genotype-dependent nature of in vitro culture protocols. Therefore, this stud...

In this study, we used extract from Roselle (Hisbiscus sabdariffa L.) Calyx to determine its ability as an antioxidant supplement to improve motility, progressive score and abnormality of goat’s sperms. Pooled semen from four male goats with average of live body weight 34.4 ± 0.6 kg and body condition score 2.5 ± 0.1 were aliquot into two groups: C...

Paphiopedilum exul, Calanthe chrysoglossoides, and Luisia brachystachys are reported here as new records for Malaysia, whereas Bryobium cordiferum subsp. borneense, Habenaria rostellifera, and Taeniophyllum rugulosum are three rare orchid species recollected from Sarawak, Perlis, and Perak, respectively. This paper highlights brief descriptions and...

The phylogenetic relationships among the Peninsular Malaysian orchid genus Coelogyne were studied by morphological characteristics and sequence data of the internal transcribed region (ITS) from the nuclear ribosomal DNA (nrDNA). Coelogyne is a large genus of about 200 species distributed in pantropical areas from the Himalayas, Sri Lanka, India, S...

Bananas are one of the world’s most consumed fruits. Developing countries in the Global South depend on bananas for food security and livelihoods. Still, the banana industry also drives a multinational trade worth billions of US dollars. In addition, banana plants also hold cultural and religious significances in many Asian countries. However, bana...

The Malayan tapir (Tapirus indicus) is an endangered species in Southeast Asia (SEA). Over the years, there has only been a few reports on its population genetic structure and evolutionary history in SEA. In particular, while the captive Malayan tapir population in Thailand has received fairly more research in recent years, there has not been any w...

Borneo Ironwood Eusideroxylon zwageri Teijsm. & Binn. has high market value for its valuable and durable timber, which has put it at risk due to illegal logging. This study analysed E. zwageri genetic variation using four microsatellite markers in populations at Nirwana Rehabilitation Forest (NRF), and Tatau, Sarawak. We found that 20.1% of total g...

Priming of seed is an approach that imparts stress tolerance to germinating seeds and seedlings under stressful conditions. Drought stress is a key reason for crop failures. We evaluated the effects of seed priming with 2.5% & 5% & KNO3 and 3% & 3.5% SiO2 on germination, seedling growth, protective enzymes and biochemical attributes of 3-weeks old...

The floral micromorphology of critically endangered Paphiopedilum Pfitzer [P. barbatum (Lindl.) Pfitzer, P. callosum var. sublaeve (Rchb.f.) P.J.Cribb and P. niveum (Rchb.f.) Stein] were analyzed concerning either infrageneric taxonomy or physioecological demands. The first two species are phylogenetically close and superficially identical but occu...

Rice is an important staple crop produced and consumed worldwide. However, poor seed emergence is one of the main impediments to obtaining higher yield of rice especially in hot and dry ecosystems of the world that are ravaged by drought. Therefore, this study was carried out to evaluate the effects of potassium nitrate (KNO3), salicylic acid (SA)...

Background: Coelogyne kaliana , Coelogyne stenochila and Coelogyne tiomanensis are three valuable rare orchid species endemic to Peninsular Malaysia, currently rampantly traded illegally via the internet and through local nurseries, which label them as hybrids to avoid enforcement detection. Drastic measures to ensure the continued existence of the...

Hibiscus sabdariffa L. is no stranger to the field of pharmacology, as its calyx extract is highly rich in beneficial compounds and has been demonstrated to possess antihyperglycemic, antihypertension, anticancer and antioxidant properties. Thus, it is labeled it as a functional food with great health benefits and therapeutic potentials. The medici...

There are many approaches to develop microsatellite markers. Despite the availability of the more advanced technology in the market, due to budget constraints, we revisited an easy and rapid polymerase chain reaction (PCR) cloning-sequencing method to design microsatellite markers for Tapirus indicus. Using six random amplified microsatellite marke...

Background: Coelogyne kaliana , Coelogyne stenochila and Coelogyne tiomanensis are three valuable rare orchid species endemic to Peninsular Malaysia, currently rampantly traded illegally via the internet and through local nurseries, which label them as hybrids to avoid enforcement detection. Drastic measures to ensure the continued existence of the...

Crepidium amplectens and Crepidium lowii are reported as two newly recorded Crepidium species belong to sect. Commelinodes from Peninsular Malaysia. The taxonomic affinity is discussed and validated involving another two of their complexes, Crepidium micranthum and Crepidium rheedei subsp. rheedei, to which they share some similar characteristics o...

This study was conducted to determine the influence of physico-chemical parameters to the distribution and succession of phytoplanktons of Putrajaya Lake and wetlands. Water sampling was conducted at three selected sampling sites (water input: Site 1, natural remediation; Site 2 and lake activity centre: Site 3) from November 2017 to January 2018,...

Rice is an important cereal consumed globally, however, poor germination and non-uniform seedling establishment are major causes of low rice yield in water-limiting arid ecosystems. Seed priming study with KNO3, SA and SiO2 to enhance germination and seedling growth was carried out with the objectives of (1) to determine the effects of seed priming...

A molecular sexing method by polymerase chain reaction (PCR) amplification of a portion of the sex-determining region Y (SRY) and the zinc finger (ZF) gene, as well as six equine Y-chromosome-specific microsatellite markers, were tested in the Malayan tapir (Tapirus indicus). While the microsatellite markers did not yield any male-specific amplicon...

Macaca fascicularis, also known as the cynomolgus macaque, is an important non-human primate animal model used in biomedical research. It is an Old-World primate widely distributed in Southeast Asia and is one of the most abundant macaque species in Malaysia. However, the genetic structure of wild cynomolgus macaque populations in Malaysia has not...

Belian tree (Eusideroxylon zwageri Teijsm. & Binn.) is one of the highly demanded commercial timber tree indigenous to the Southeast Asian region. The tree is threatened with over exploitation; habitat destruction and slow regeneration. While vascular plants are known as major reservoirs of fungi species, there have been no studies to identify the...

Stevia rebaudiana, a perennial herb native to northeastern Paraguay, has gained immense attention globally over the recent decades due to the natural sweetness of its leaves. Like in most plants, this particular species contains high amount of secondary metabolites, thus rendering the isolation of high quality and quantity RNA extract for molecular...

In this study, the efficacy of four DNA markers and their combinations (rbcL, matK, ITS, trnH-psbA) as barcode markers were tested across the endangered Paphiopedilum species from Peninsular Malaysia. Four species of Paphiopedilum were sampled and barcoded. The DNA barcodes reliabilities were evaluated using NCBI BLASTn program, phylogenetic tree v...

Objective Using high-throughput RNA sequencing technology, this study aimed to sequence the transcriptome of kidney and liver tissues harvested from Peninsular Malaysia cynomolgus macaque (Macaca fascicularis). M. fascicularis are significant nonhuman primate models in the biomedical field, owing to the macaque’s biological similarities with humans...

There are many approaches to develop microsatellite markers. We revisited an easy and rapid Polymerase Chain Reaction (PCR)-cloning-sequencing method to design microsatellite markers for Tapirus indicus. Using six random amplified microsatellite (RAM) markers, this study had rapidly generated 45 unique genomic sequences containing microsatellites....

Gunung Tahan is the highest mountain peak in Peninsular Malaysia (2187 m a.s.l.) and is a part of Taman Negara Pahang that houses many rare and endemic species of flora and fauna. This account is conducted to evaluate, compile, and update the orchids collections from Gunung Tahan after almost 126 years, since the first botanical exploration was con...

Flavonoids are polyphenolic compounds commonly found in vegetables as well as fruits and contribute significantly in the human diet. The calyx of roselle (Hibiscus sabdariffa L.) is rich in polyphenolic compounds and anthocyanins. Chalcone synthase (CHS) and flavanone 3-hydroxylase (F3H) are two important genes involved in the biosynthesis of flavo...

Sexual dimorphism is often directly linked to sexual selection, mating systems and resource partitioning, which are crucial in species conservation and management. Many avian species, including pollinator birds, are sexually dimorphic with respect to size and colour, yet, such differences may be subtle for some species. In this study, molecular sex...

Human health may be at risk when consuming edible but metal-contaminated aquatic plants. This present study was conducted to evaluate the bioavailabilities of manganese (Mn) and cadmium (Cd) in metalscontaminated wild water spinach (WWS), Ipomoea aquatic Forssk. through in vitro human gastrointestinal digestions. Additionally, the health risks from...

The cynomolgus macaque ( Macaca fascicularis ) is an extensively utilised nonhuman primate model for biomedical research due to its biological, behavioural, and genetic similarities to humans. Genomic information of cynomolgus macaque is vital for research in various fields; however, there is presently a shortage of genomic information on the Malay...

Box plot lymph vs. spleen

Principal component analysis lymph vs. thymus

Box plot spleen vs. thymus

Antigen processing and presentation

Protein processing in endoplasmic reticulum

Ras signalling pathway

Rap1 signaling pathway

RNA degradation

Differentially expressed genes

Tissue-specific genes

Principal component analysis lymph vs. spleen

Principal component analysis spleen vs. thymus

Platelet activation

B cell receptor signaling pathway

Intestinal immune network for IgA production

TNF signaling pathway

Individual Library Mapping Statistics

Comparison with Peng et al., 2014

Box plot lymph vs. thymus

Unmapped-reads assignment charts

Gene validation

The long-tailed macaque (Macaca fascicularis) is commonly used for biomedical researches. However, genetic variation within a population or among populations can significantly affect phenotypical outcomes of treatments tested on model organisms. As such, it is important for studies involving model organisms originating from different, or even the s...

Polluted ponds and lakes close to agricultural activities become the exposure route of manganese (Mn) and cadmium (Cd) to aquatic plants in near vicinity. Therefore, a study of the uptake, bioaccumulation, and translocation of Mn and Cd by the water spinach (Ipomoea aquatica) is presented in this paper. Different concentrations of Mn and Cd were ad...

Gunung Jerai, Kedah is one of the isolated peaks in Peninsular Malaysia. Although many botanists and collectors have explored Gunung Jerai for more than 150 years, no study was specifically conducted on the diversity of orchids in the area. The purpose of this study is to produce an updated checklist of the orchids focusing only the summit area fro...

Understanding the genetic variation of the Plasmodium parasites could play an important role in controlling and preventing this lethal infection. Inter simple sequence repeat (ISSR) markers have successfully been tested for investigating the genetic diversity of malaria vectors. It is hypothesized that ISSRs could lead to fruitful results in studyi...

The Hibiscus sabdariffa var. UMKL (Roselle) investigated here may potentially be used as an alternative fibre source. To the best of our knowledge, there was no study focusing on the genetics underlying the cellulose biosynthesis machinery in Roselle thus far. This paper presents the results of the first isolation of the cellulose synthase gene, Hs...

This study was conducted to determine seed germination on the mechanisms of salinity stress in B. rapa var. parachinensis (Hong kong choy sum). The type of experiment was a completely randomized design with three salinity treatment NaCl, MgCl2, and KCl and minimum four replications was used. Salinity treatment consisted of 0 (control), 50, 100, 150...