Areas In Peninsular Malaysia Research Articles

Unveiling the Gut Microbiome of Malaysia's Colobine Monkeys : Insights into Health and Evolution.

Colobines are primarily leaf-eating primates, depend on microbiota of gastrointestinal tracts for food digestion. However, the gut microbiota of Malaysia's colobines specifically langurs remains unstudied. Hence, we aim to analyze the fecal microbiomes of Malaysia's langurs using Presbytis femoralis, Presbytis robinsoni, Trachypithecus obscurus, and Trachypithecus cristatus from various landscapes as models. We collected samples from all four species across several areas in Peninsular Malaysia and performed 16S ribosomal RNA gene amplicon sequencing using the Illumina sequencing platform. Presbytis femoralis exhibited the highest bacterial diversity, followed by T. obscurus, T. cristatus, P. robinsoni and the lowest, P. siamensis. Over 11 million operational taxonomic units (OTUs) were identified across Malaysia's langurs spanning 26 phyla, 180 families, and 329 genera of microbes. The OTUs were dominated by Firmicutes, Proteobacteria, and Bacteroidetes. There are 11 genera of pathogenic bacteria were identified across all host species. Nine pathogenic bacterial genera inhabit both T. obscurus, indicating poor health due to low bacterial diversity and heightened pathogenicity. In contrast, P. robinsoni with the fewest pathogenic species is deemed the healthiest among Malaysia's langurs. This study demonstrates that alterations in diet, behavior, and habitat affect bacterial diversity in Malaysia's langurs' gut microbiota. Even though this is the first comprehensive analysis of langur microbiomes in Malaysia, it is important to note the limitations regarding the number of samples, populations sampled, and the geographical origins and landscapes of these populations. Our results suggest that Malaysia's langurs may harbor pathogenic bacteria, potentially posing a risk of transmission to humans. This highlights the critical need for the conservation and management of Malaysia's langurs, particularly considering their interactions with humans. This data can serve as a foundation for authorities to inform the public about the origins and significance of animal health and the management of zoonotic diseases.

Examining direct and indirect flood damages in residential and business sectors through an empirical lens.

Investment to reduce flood risk for social and economic wellbeing requires quantitative evidence to guide decisions. Direct and indirect flood damages at individual household and business building levels were assessed in this study using multivariate analysis with three groups of flood damage attributes, i.e., flood characteristics, socioeconomic conditions, and building types. A total of 172 and 45 respondents from residential and commercial buildings were gathered through door-to-door interviews at areas in Peninsular Malaysia that were pre-identified to have frequently flooded. Two main findings can be drawn from this study. First, flood damage is greatly contributed by high-income households and businesses, despite them being less exposed to floods than low-income earners. This supports the current use of mean economic damage in engineering-based flood intervention analysis. Second, indirect damages increase with the increase in family size, indicating the importance of strengthening preparedness and social support to those with great social responsibility. Overall, the study highlights the importance of holistic flood management accounting for both direct and indirect losses.

Using sustainability pillar indicators to evaluate the management effectiveness of three protected areas in the state of Selangor, Peninsular Malaysia

The existing methodologies to measure management effectiveness of protected area have often been focus on identifying weaknesses and strengths to set priorities in terms of policy intervention, resource distribution and adaptive management. It is not adequately captured the extent of protected area sustainability as a conservation site even though management effectiveness is influenced by the interaction of environment, socioeconomics and governance, which are pillars of sustainability. Thus, the objective of this study was to propose a methodology based on sustainability pillar indicators to evaluate management effectiveness, using three protected areas in Peninsular Malaysia as case studies: Sungai Dusun, Bukit Kutu and Klang Gate wildlife reserves. In this study, a questionnaire survey was used to evaluate the management effectiveness of the study sites. The evaluation framework of the questionnaire was based on six components of management effectiveness and indicators from three sustainability pillars or aspects: environment, socioeconomics and governance. Respondents of the survey consisted of local residents in each study site and management staff involved in the management of the protected areas. Each indicator from different aspects of evaluation was assigned a selected parameter to be rated by the respondents from ‘1’ (strongly disagree) to ‘5’ (strongly agree). Based on the rating values the percentage of optimum value was calculated to determine the overall management rating for each study site which interpreted according to five management levels from ‘unsatisfactory’ to ‘very satisfactory’. The percentage of optimum values revealed that the environment and governance aspects of all study sites had moderately satisfactory while for socioeconomic only Klang Gate had moderately satisfactory but satisfactory for Bukit Kutu and Sungai Dusun. The overall percentage of optimum revealed that the management effectiveness level of all reserves was moderately satisfactory. However, Sungai Dusun had the highest percentage of optimum (71.3%), followed by Bukit Kutu (67.7%) and Klang Gate (66.5%). In conclusion, the sustainability level of the reserves is still functioning as intended despite deficiencies especially in governance aspect. Thus, the proposed methodology is simple and has adoptable way to measure both management effectiveness and capture the sustainability of the protected areas.

Relationships between Air Pollutants and Meteorological Factors during Southwest and Northeast Monsoon at Urban Areas in Peninsular Malaysia

People who currently live in urban areas are subjected to significantly higher levels of exposure to air pollution. Pollutant concentrations in the air change according to the weather, the locations of the many sources of pollution, and the topography of the area. This study examines the link between meteorological parameters (ambient temperature, relative humidity, and wind speed) and daily air pollutant concentrations in four monitoring stations at Peninsular Malaysian cities (Seberang Perai, Pasir Gudang, Batu Muda, and Kemaman) during southwest and northeast monsoon. Pearson Correlation Analysis analyzed air quality data over two years (January 2016 - January 2018). The study found that PM10 concentrations were highest at all monitoring locations. At all monitoring locations, climatic parameters correlated with NO2, PM10, and CO. Air pollution and meteorological conditions correlate weakly to moderately during the southwest monsoon. The investigation found that weather conditions affect O3 most during the dry season. CO and climatic parameters correlated weakly at all four monitoring stations during the northeast monsoon. PM10 correlated positively with ambient temperature and negatively with relative humidity and wind speed at all four stations. The northeast monsoon correlation values were weak to moderate. This study will help officials identify optimal air pollution controls for metropolitan areas during monsoon seasons in line with SDG-11, which promotes sustainable cities and communities.

Screening of Streptococcus suis in swine workers of selected states in Peninsular Malaysia.

Streptococcus suis is a zoonotic pathogen that is highly associated with contact between live pigs and raw pig material. In view of the recent reports of human infections in Malaysia, epidemiological data on the status of S. suis in the human population, especially among people working closely with pigs and/or raw pork, should be provided. The aim of this study was to detect S. suis among individuals working in the swine industry in several major pig production areas in Peninsular Malaysia. Demographic information, exposure determinants, and oral swabs were collected from swine personnel, including farmers, butchers, and veterinarians. Oral swabs were subjected to bacterial isolation and conventional polymerase chain reaction (PCR) assays for S. suis detection. The study included 40 participants working in the swine industry, with a predominant representation of males (62.5%) and Malaysian Chinese individuals (60.0%) who consumed pork (92.5%). Notably, none of the participants reported consuming raw or partially cooked pork. In spite of their occupational exposure risk, none of the oral swabs showed positive results for S. suis infection. To the best of our knowledge, this is the first report and detection study of S. suis using oral swabs obtained from swine personnel in Peninsular Malaysia.

Ground-Level Particulate Matter (PM2.5) Concentration Mapping in the Central and South Zones of Peninsular Malaysia Using a Geostatistical Approach

Fine particulate matter is one of the atmospheric contaminants that exist in the atmosphere. The purpose of this study is to evaluate spatial–temporal changes in PM2.5 concentrations in the central and south zones of Peninsular Malaysia from 2019 to 2020. The study area involves twenty-one monitoring stations in the central and south zones of Peninsular Malaysia, using monthly and annual means of PM2.5 concentrations. The spatial autocorrelation of PM2.5 is calculated using Moran’s I, while three semi-variogram models are used to measure the spatial variability of PM2.5. Three kriging methods, ordinary kriging (OK), simple kriging (SK), and universal kriging (UK), were used for interpolation and comparison. The results showed that the Gaussian model was more appropriate for the central zone (MSE = 14.76) in 2019, while the stable model was more suitable in 2020 (MSE = 19.83). In addition, the stable model is more appropriate for both 2019 (MSE = 12.68) and 2020 (8.87) for the south zone. Based on the performance indicator, universal kriging was chosen as the best interpolation method in 2019 and 2020 for both the central and south zone. In conclusion, the findings provide a complete map of the variations in PM2.5 for two different zones, and show that interpolation methods such as universal kriging are beneficial and could be extended to the investigation of air pollution distributions in other areas of Peninsular Malaysia.

Pro-Environmental Behavior Decisions in Face Mask Usage: A Pilot Study

Human behavior and interaction with their surroundings vary from one another. Different people may engage and behave pro-environmental based on their beliefs and understanding of the consequences of environmental problems for themselves. The theory of planned behavior (TPB) and value belief norm theory (VBN) suggest that an individual perceives environmental pollution effects could influence their decision-making in daily activities. This study aimed to examine people's behavior in using face masks and their perception of environmental consequences by integrating the TPB and VBN into a single conceptual framework. This study confirms that sub-factors, including biosphere, altruism, egoistic, awareness of consequences, and personal norms, are among the predictors that explain pro-environmental behavior in Malaysia. Additionally, the cultural factor significantly mediates the behavior. A questionnaire pilot survey was conducted among 50 visitors in a coastal area in Peninsular Malaysia. The Cronbach alpha test and descriptive analysis confirm the direct and mediatory effect of the causal of the variables in the TPB and VBN theory of pro-environmental behavior when making decisions in face mask usage. The research results validate the proposed TPB and VBN theory model linkages to clarify pro-environmental behavior.

Analysis of trends in extreme temperature indices over selected areas in Peninsular Malaysia from 1991-2020

This study investigates the temporal variations of extreme temperature trends across three stations in Peninsular Malaysia with different settings, Petaling Jaya represents urban station, while Kluang and Batu Embun represent rural areas from 1991-2020. Eleven extreme warm and cold indices trends were analysed using the Mann-Kendall test, with Sen’s slope as a magnitude estimator. The findings revealed that the annual daily mean temperature, daily mean maximum temperature, and daily mean minimum temperature increased significantly at all stations by 0.04°C yr–1, 0.02°C yr–1, and 0.05°C yr–1, respectively. The station in the rural area shows a significant increment of an average of 0.03°C yr–1 for mean and warm extreme indices. Despite that, there were no changes in the total number of warm days and nights and cold days and nights for all settings. For the cold temperature indices, there were significant decreasing trends for the annual minimum of maximum temperature in rural areas, while urban station did not exhibit changes. All stations also exhibit similar annual patterns when compared although significantly higher readings were observed during El Niño events.

Distribution of Six Urban Bird Species in Urban Agglomeration of Central Region of Peninsular Malaysia Using Ebird Database

Developing countries are undergoing rapid urbanisation to fulfil the high demands of incremental population growth, construction, and development. Excessive development has negative impacts on biodiversity by altering or destroying habitats. However, each bird species may respond differently to habitat alteration. Therefore, this study was conducted to determine the distribution of urban bird species in metropolitan cities and nearby areas in Peninsular Malaysia. The main objective of this study was to determine the distribution patterns of six aesthetically valuable urban bird species (Black-naped Oriole [Oriolus chinensis], Yellow-vented Bulbul [Pycnonotus goiavier], White-throated Kingfisher [Halcyon smyrnensis], Pink-necked Green-Pigeon [Treron vernans], Coppersmith Barbet [Psilopogon haemacephalus] and Common Iora [Aegithina tiphia]) in Greater Kuala Lumpur (the Klang Valley region) using observations from a citizen science (eBird) database. We mapped species abundance throughout the focal area using ArcGIS and analysed the data using Minitab. Three urban bird species dominated, with the highest number of observations recorded: Yellow-vented Bulbul (46.59%), Pink-necked Green-Pigeon (19.25%), and Black-naped Oriole (13.00%). While, the Coppersmith Barbet had the lowest recorded observations (2.76%). Species abundance differed significantly across the study region (F=5.12,p<0.05), with the studied species’ occurrence increasing as green spaces increased. Such dynamic mapping is crucial for better understanding the mechanisms of the persistence of urban biodiversity. We suggest creating more green areas and planting roadside trees to provide green corridors within cities to help sustain urban biodiversity.

Dietary Inflammatory Index, Obesity, and the Incidence of Colorectal Cancer: Findings from a Hospital-Based Case-Control Study in Malaysia

Obesity-mediated inflammation represents a key connection between the intake of foods with high inflammatory potential and colorectal cancer (CRC) risk. We aimed to explore the association between energy-adjusted dietary inflammatory index (E-DII) in relation to CRC risk in both obese and non-obese subjects. This study included 99 histopathologically confirmed CRC cases, 73 colonic polyps cases, and 141 healthy controls from tertiary medical centres in both urban and suburban areas in Peninsular Malaysia. The subjects were categorised into body mass index (BMI) < 25 kg/m2 and BMI ≥ 25 kg/m2 groups. E-DII scores were computed based on dietary intake assessed using a validated food frequency questionnaire (FFQ). Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for potential cofounders. The mean dietary energy intake and mean BMI values of the subjects tended to increase as the E-DII scores increased (p for trend < 0.001). E-DII was significantly related to CRC risk only in obese subjects (OR = 1.45; 95% CI = 1.30-1.77; p < 0.001 for trend). Stratified analyses of risk factors showed significant associations between E-DII and CRC risk by age group (p for interaction = 0.030), smoking status (p for interaction = 0.043), and anthropometric indices for both males and females (p for interaction < 0.001) in the most pro-inflammatory E-DII quartile vs. the lowest E-DII quartile. Overall, pro-inflammatory diets were associated with an increased incidence of CRC in the Malaysian population, particularly in obese subjects.

MAPPING TRENDS OF CARBON DIOXIDE AND METHANE DURING MOVEMENT CONTROL ORDER IN INDUSTRIAL AREAS IN PENINSULAR MALAYSIA USING GOSAT, GOSAT-2, OCO-2, OCO-3, AND TROPOMI SATELLITES DATA

Abstract. The Malaysian government implemented the Movement Control Order (MCO) from March 18 to May 13, 2020, in an effort to curb the coronavirus disease outbreak that had spread throughout the nation. Utilizing data from GOSAT, GOSAT-2, OCO-2, OCO-3, and TROPOMI, the total column-averaged dry-air mole fraction of carbon dioxide and methane (referred as XCO2 and XCH4) is employed to examine the patterns of both gases throughout the MCO as well as from the same period the prior and following year. The Inverse Distance Weighting (IDW) interpolation method is utilized in mapping the XCO2 and XCH4 for the industrial areas in Peninsular Malaysia. The results revealed that even MCO is implemented, the XCO2 and XCH4 in the industrial areas are increasing year by year. By using satellites data, the XCO2 and XCH4 from large areas can be monitored continuously.

Morphological Variations of Weedy Rice (Oryza sativa ssp.) In Selected Rice Fields of Peninsular Malaysia

Weedy rice or locally known as ‘padi angin’ has been infesting rice granary areas in Malaysia for the last 20 years. The outbreak of weedy rice in the country started during the late 1980s in Projek Barat Laut Selangor (PBLS) due to the adoption of direct-seeding practices. Weedy rice can be characterized by its early maturing and easy-shattering traits. The objective of this study was to determine the morphological variations of weedy rice in selected granary areas located in Peninsular Malaysia. A total of 110 weedy rice accessions were collected from nine locations in three granary areas in Peninsular Malaysia (the Western, Eastern, &amp; Northern regions). The collected weedy rice accessions were planted under greenhouse conditions to study their morphological features. Results of the present study indicated that 73.6% of weedy rice accessions were awnless while the remaining 26.4% produced awn. Selected traits such as plant height, flag leaf length, culm length, number of tillers, number of panicles, and panicle length were included in the Principal Component Analysis (PCA). The weedy rice accessions were grouped into three different clusters mainly Cluster 1: cultivated rice and awnless populations, Cluster 2: brown and red pericarp awnless populations, and Cluster 3: awned populations. The findings of this study may be used as guidance for farmers and researchers for designing sustainable weedy rice management in the future.

Determining the diet of wild Asian elephants (Elephasmaximus) at human-elephant conflict areas in Peninsular Malaysia using DNA metabarcoding.

Human-elephant conflict (HEC) contributes to the increasing death of Asian elephants due to road accidents, retaliatory killings and fatal infections from being trapped in snares. Understanding the diet of elephants throughout Peninsular Malaysia remains crucial to improve their habitat quality and reduce scenarios of HEC. DNA metabarcoding allows investigating the diet of animals without direct observation, especially in risky conflict areas. The aim of this study was to determine: i) the diet of wild Asian elephants from HEC areas in Peninsular Malaysia using DNA metabarcoding and ii) the influence of distinct environmental parameters at HEC locations on their feeding patterns. DNA was extracted from 39 faecal samples and pooled into 12 groups representing the different sample locations: Kuala Koh, Kenyir, Ulu Muda, Sira Batu, Kupang-Grik, Bumbun Tahan, Belum-Temengor, Grik, Kampung Pagi, Kampung Kuala Balah, Aring 10 and the National Elephant Conservation Centre, which served as a positive control for this study. DNA amplification and sequencing targeted the ribulose-bisphosphate carboxylase gene using the next-generation sequencing Illumina iSeq100 platform. Overall, we identified 35 orders, 88 families, 196 genera and 237 species of plants in the diet of the Asian elephants at HEC hotspots. Ficus (Moraceae), Curcuma (Zingiberaceae), Phoenix (Arecaceae), Maackia (Fabaceae), Garcinia (Clusiaceae) and Dichapetalum (Dichapetalaceae) were the highly abundant dietary plants. The plants successfully identified in this study could be used by the Department of Wildlife and National Parks (PERHILITAN) to create buffer zones by planting the recommended dietary plants around HEC locations and trails of elephants within Central Forest Spine (CFS) landscape.

Criteria for the Protected Area Management Category Framework in Peninsular Malaysia for Sustainable Conservation Planning

The categories of protected area management are essential tools for ensuring the agenda of conserving biodiversity is achieved. Almost all countries in the world have established the management categories intending to provide the guidelines to manage the conservation site. Peninsular Malaysia is not exceptional and the management categories are following the International Union for Conservation of Nature (IUCN). It has been implemented since 1996 specifically for all protected areas managed by the Department of Wildlife and National Parks (DWNP). However, the implementation is done without using any criteria and sub-criteria in assigning the management category to each protected area. Therefore, the objective of this article is to highlight the criteria and sub-criteria that need to be considered in the management category framework of protected areas in Peninsular Malaysia. All criteria/sub-criteria were identified through a literature review, followed by filtering, integration and expert validation. A total of 46 sub-criteria were identified and can be categorized into 5 criteria: general, environmental, social, economic and management. For sustainable conservation planning all the identified criteria and sub-criteria are essential for determining the management categories of protected areas in Peninsular Malaysia.

Quantifying NO2 Reduction Before and During Covid-19 Movement Control Order In Major Cities And Industrial Area In Peninsular Malaysia Using Satellite Data Observation

Movement Control Order (MCO) which was the restrictions or the lockdown that were implemented by the government of Malaysia from 18 March 2020 to 31 March 2020. Our study aims to evaluate Nitrogen Dioxide (NO2) changes, before and during the MCO in Malaysia’s major cities especially the Klang Valley area as well as some industrial areas in the country. Tropospheric NO2 vertical column density from the TROPOspheric Monitoring Instrument (TROPOMI) was used to evaluate the spatial-temporal variations of the NO2 before and during the first phase of the MCO for the entire Peninsular. It is found that the NO2 concentrations is very prominent in Greater Klang Valley (GKV) but those location outside the GKV are related to Power Plant Stations in the country. Reduction of NO2 quantified by TROPOMI satellite showed a sharp decline for the daily readings, with the highest differences in Greater Klang Valley urban stations (− 52%) in Cheras, followed by Shah Alam (-43%). The lowest decline was recorded in Putrajaya with only (− 18%). The industrial site locations mostly show neutral readings or low increments as low as 5%. Only the location in Johor Bahru shows a very sharp increase up till 142% perhaps due to the ‘business as usual’ of the neighbouring country. Medium correlation between ground measurement and TROPOMI column was obtained for the Greater Klang Valley locations R=0.455 before the MCO implementation, and R=0.588 after the MCO implementation. These results suggested that air pollution improvement in Greater Klang Valley area is gained from the implementation of the government full scale MCO or lockdown measures. The transportation activities played the key role in decreasing the NO2 level in Greater Klang Valley.

Exploring Community Perceptions of Climate Change Issues in Peninsular Malaysia

The urbanization process in Peninsular Malaysia has resulted in an increase in temperature. Large cities such as Kuala Lumpur, Johor Bharu, and George Town are experiencing rapid urbanization processes, resulting in unpredictable changes in temperature and weather, which consequently impact community livelihoods. Many believe that the recent flooding in urban residential areas in Peninsular Malaysia has been worsened by climate change. Hence, this paper explores and discusses recent community perceptions of the climate change issue in Peninsular Malaysia. A group of 350 community members from different states in Peninsular Malaysia gave their views and opinions related to climate change via an online quantitative survey questionnaire. Their perception of the urbanization process and its impact on the increase in temperature was descriptively analyzed using the frequency analysis technique and mean score, while their suggestions in verbatim form on reducing the effects of climate change were analyzed thematically. The respondents perceived the climate change issue as attributable to the factors of urbanization, namely the manufacturing industry, population density, and private motor vehicles. Respondents provided suggestions for reducing the effects of climate change, ranging from government policies to community actions.

Perception of Death among Young Adults in Multicultural Peninsular West Malaysia: The Abrahamics and Dharmics

The topic of death perception is often a matter related to older people. As there is a paucity of studies with the young population, insights into their views would be helpful to healthcare professionals who may be confronted by events of death and dying. This study is aimed at exploring the perception of death among young adults of different religions in a multi-cultural and multi-faith society as in Malaysia. A total of 32 participants representing the main religious groups, i.e., Islam, Christianity, Buddhism and Hinduism were recruited from the Klang Valley area of Peninsular Malaysia. Focus group discussions were undertaken with participants grouped according to their religious identifications. Five themes emerged from the data: (a) Belief in Afterlife, (b) Fear of Own Death, (c) Fear of Others&amp;rsquo; Death, (d) Preparation towards Death and Afterlife, and (e) Way of Living. In a diverse and polarised society such as in conservative Malaysia, insights into death perceptions of different main groups of people can play a significant role in the provision of health care.

SHARPENING OF THERMAL SATELLITE IMAGERY FROM KLANG INDUSTRIAL AREA IN PENINSULAR MALAYSIA USING THE TSHARP APPROACH

Abstract. Measuring high spatial/temporal industrial heat emission (IHE) is an important step in industrial climate studies. The availability of MODIS data products provides up endless possibilities for both large-area and long-term study. nevertheless, inadequate for monitoring industrial areas. Thus, Thermal sharpening is a common method for obtaining thermal images with higher spatial resolution regularly. In this study, the efficiency of the TsHARP technique for improving the low resolution of the MODIS data product was investigated using Landsat-8 TIR images over the Klang Industrial area in Peninsular Malaysia (PM). When compared to UAV TIR fine thermal images, sharpening resulted in mean absolute differences of about 25 °C, with discrepancies increasing as the difference between the ambient and target resolutions increased. To estimate IHE, the related factors (normalized) industrial area index as NDBI, NDSI, and NDVI were examined. The results indicate that IHE has a substantial positive correlation with NDBI and NDSI (R2 = 0.88 and 0.95, respectively), but IHE and NDVI have a strong negative correlation (R2 = 0.87). The results showed that MODIS LST at 1000 m resolution can be improved to 100 m with a significant correlation R2 = 0.84 and RMSE of 2.38 °C using Landsat 8 TIR images at 30 m, and MODIS LST at 1000 m resolution can still be improved to 100 m with significant correlation R2 = 0.89 and RMSE of 2.06 °C using aggregated Landsat-8 TIR at 100 m resolution. Similarly, Landsat-8 TIR at 100 m resolution was still improved to 30 m and used with aggregate UAV TIR at 5 m resolution with a significant correlation R2 = 0.92 and RMSE of 1.38 °C. Variation has been proven to have a significant impact on the accuracy of the model used. This result is consistent with earlier studies that utilized NDBI as a downscaling factor in addition to NDVI and other spectral indices and achieved lower RMSE than techniques that simply used NDVI. As a result, it is suggested that the derived IHE map is suitable for analyzing industrial thermal environments at 1:10,000 50,000 scales, and may therefore be used to assess the environmental effect.

First Report of Fusarium equiseti, Causing Fruit Rot Disease of Watermelon in Malaysia.

Watermelon (Citrullus lanatus) accounts for almost 13% of all tropical fresh fruit production in Malaysia. They are grown, mostly in Johor, Kedah, Kelantan, Pahang, and Terengganu areas of Malaysia on 10,406 ha and yielding 172,722 Mt. In 2019, a new fruit rot disease was observed in two major production areas in Peninsular Malaysia. Disease symptoms included water-soaked brown lesions on the fruit surface in contact with the soil. The lesions enlarged gradually and ultimately covered the whole fruit with white mycelium leading to internal fruit decay. Disease surveys were conducted in December 2019 and November 2020 in fields at Kuantan, Pahang and Serdang, Selangor. Disease incidence was 10% in 2019 and 15% in 2020. Infected fruits were collected and washed under running tap water to wash off adhering soil and debris. Fruit tissue sections 1 to 2 cm in length were surface sanitized with 0.6% sodium hypochlorite (NaOCl) for 3 min. and washed twice with sterile distilled water. The disinfected air-dried tissues were then transferred onto potato dextrose agar (PDA) media and incubated at 25±2℃ for 3 days. Fungal colonies with whitish mycelium and pink pigment isolated using single spore culture. The pure cultures were placed onto carnation leaf agar (CLA), and the culture plates were incubated at 25±2℃ for 15 days for morphological characterization. On CLA, macroconidia were produced from monophialides on branched conidiophores in orange sporodochia. Macroconindia were thick-walled, strong dorsiventral curvature, 5 to 7 septate with a tapered whip-liked pointed apical cell and characteristic foot-shaped basal cell, 21.9 to 50.98 μm long and 2.3 to 3.60 μm wide. Typical verrucose thick chlamydospores with rough walls were profuse in chains or clumps, sub-globose or ellipsoidal. Based on morphological characteristics they were identified as Fusarium equiseti (Leslie and Summerell 2006). Molecular identification of both U4-1 and N9-1 pure culture isolates were carried out using two primer pair sets; internal transcribed spacer (ITS) ITS-1/ ITS-4 and translation elongation factor 1 alpha (TEF1-α) (EF-1/EF-2). A Blastn analysis of the ITS gene sequence of U4-1(MW362286) and N9-1 (MW362287) showed >99% similarity index to the reference gene sequence of F. equiseti isolate 19MSr-B3-4 (LC514690). The TEF1-α sequences of U4-1 (accession no. MW839563) and N9-1 (accession no. MW839564) showed 100% identity; with an e-value of zero, to the reference gene sequence of F. equiseti isolate URM: 7561 (accession no. LS398490). Each isolate also had a >99% identity with isolate NRRL 34070 (accession no. GQ505642) in Fusarium MLST database that belongs to the F. incarnatum-equiseti species complex (O'Donnell et al. 2015). Based on phylogenetic analysis of the aligned sequences (TEF1-α) by the maximum likelihood method, the U4-1 and N9-1 isolates were confirmed to be F. equiseti as was reported in Georgia, USA (Li and Ji 2015) and in Harbin, Heilongjiang Province, China (Li et al. 2018). Finally, the two pure culture isolates of U4-1 and N9-1 were used to fulfill Koch's postulates. Stab inoculations of five healthy watermelon fruits (cv. 345-F1 hybrid seedless round watermelon) were performed with a microconidial suspension of individual isolates (4x106 spores/mL). Five control fruits were stabbed with double distilled water. The inoculated fruits were incubated under 95% relative humidity at a temperature of 25±2℃ for 48 h followed by additional incubation inside an incubator at 25±2℃ for 8 days. Ten days post-inoculation, the control fruits showed no disease symptoms. However, inoculated fruits exhibited typical symptoms of fruit rot disease like water-soaked brown lesions, white mycelium on the fruit surface and internal fruit decay, which is similar to the farmer's field infected fruits. The suspected pathogen was successfully re-isolated from the symptomatic portion of inoculated fruit and morphologically identified for verification. To our knowledge, this is the first report of F. equiseti causing fruit rot of watermelon in Malaysia. Malaysia exports watermelon year-round to many countries around the world. The outbreak of this new fruit rot disease could potentially pose a concern to watermelon cultivation in Malaysia.

Use of molecular markers and compound-specific isotopic signatures to trace sources of black carbon in surface sediments of Peninsular Malaysia: Impacts of anthropogenic activities

Black carbon (BC) acts as a reservoir of carbon in sediment due to its high persistency. Southeast Asia (SEA) is a main source region for BC emissions across the globe due to extensive biomass burning and escalating fossil fuel consumption. However, our understanding of the sources and sinks of BC in SEA is limited. Here, we have analysed BC structure using benzene polycarboxylic acid (BPCA) method in combination of stable carbon isotope (δ13C) signatures for B5CA and B6CA using HPLC-IRMS in sediment samples from riverine, coastal and shelf areas in Peninsular Malaysia. BPCA molecular markers indicated higher degree of aromatic condensation and lighter isotopic composition in relatively pristine environment of the East coast compared to developed environment of the West and South coast. n-Alkane biomarkers clearly demonstrated higher anthropogenic impacts on the sediments of the West and South coast compared to the East coast. Biomass burning with the predominance of C3 plants and the large share of natural gas in the energy mix in Malaysia are possibly the main reasons for the isotopically light composition of sedimentary BC (−45.4 to −26.4‰). Atmospheric soot and petrogenic BC are the possible main sources of BC in the East coast sediments, while char residues of low temperature biomass burning likely contribute more to sedimentary BC in the West and South coast. The n-alkane indices implied that the sediments of the Kelantan adjacent shelf area receive great proportion of terrestrial organic matter and the associated BC.