Southeast Asian Countries Research Articles

Externalities of Sanctions Impact on Russian Economy

The work reveals the economic motives for decision-making by the leading world powers and the features of the development of the Russian national economy in the context of measures taken by the Government of the country in the conditions of a changing geopolitical reality. The emphasis is made on the need to manage the risks of foreign economic activity after the introduction of anti-Russian sanctions by unfriendly countries with developed economies. The degree of dependence of the Russian Federation on high-tech goods, components, software and at the same time low diversification of production for the main export items has been revealed. Promising markets for export goods and potential importers as well as partner countries for the development of mutual trade in products and services have been identified. Acceptable solutions and current anti-crisis support measures from the state in the form of subsidizing lending rates, creating “new growth points” in the economy by allocating funds for import substitution programs, etc. are outlined. An assessment of the possible damage to several friendly countries from the attempt to economically isolate one of the world’s largest economies has been completed. The countries of Southeast Asia, Africa, and Latin America are considered the main regions for the future development of international cooperation. The BRICS bloc for Russia is becoming a key integration association in terms of transforming industrial, logistics and financial chains in the global economic space. As a result, constructive conclusions about the need to use diplomatic measures to maintain neutrality and create interstate agreements that contribute to a more intensive opening of the internal markets of friendly countries for the development of mutual trade in raw materials and high-tech goods are given.

Factors associated with stunting incidents in toddler in the working area of north wakorumba health center, North Buton District, Southeast Sulawesi Province, Indonesia, 2023

Background: The problem of children's nutritional health which is currently the government's main priority to be addressed immediately is child growth and development. One of the problems with children's growth and development that is often encountered is stunting. Indonesia is the fifth country with the highest prevalence of stunting in the world with a figure reaching 37%. Meanwhile, in the Southeast Asia region, Indonesia is ranked second with the highest prevalence of stunting compared to other countries in Southeast Asia. results of the 2022 Indonesian Nutrition Study the prevalence of stunting under five (TB/U) based on districts/cities in Southeast Sulawesi Province, namely Central Buton Regency, was ranked first (41.6%) Objective: This study aims to determine factors related to the incidence of stunting among toddlers in the working area of the North Wakorumba Community Health Center, North Buton Regency in 2023. Method: The type of research used in this research is observational analytics with a case controll study approach. The sampling technique used is simple random sampling. The total sample was 150 respondents. The analysis used is the chi-square test. Results: This research shows that there is a relationship between maternal knowledge (p-value = 0.000), family income (p-value = 0.048), exclusive breastfeeding (p-value = 0.001), maternal parenting style (p-value = 0.008) and not There is a relationship between history of infectious diseases (p-value = 0.158) with the incidence of stunting in toddlers in the North Wakorumba Health Center Working Area, North Buton Regency. Conclusion: There is a relationship between maternal knowledge, family income, exclusive breastfeeding and maternal parenting patterns on the incidence of stunting in toddlers and there is no relationship between history of infectious disease and the incidence of stunting in toddlers in the working area of North Wakorumba Community Health Center, North Buton Regency in 2024. So that the Community Health Center It is necessary to increase the intensity of outreach to increase community knowledge and enthusiasm in managing family nutrition.

Reactogenicity of Primary Vaccination with Hexavalent Vaccines in Infants: Mathematical Projections in Four Southeast Asian Countries

Reactogenicity of Primary Vaccination with Hexavalent Vaccines in Infants: Mathematical Projections in Four Southeast Asian Countries

Systematic Review of Parents with Autism Spectrum Disorder (ASD) Children in Southeast Asia: Work-related Factors

Considering the rising cases of ASD among children, this paper aims to investigate the extent to which work-related factors have been examined in studies conducted on parents of children with ASD within the Southeast Asia (SEA) region. Using the PRISMA framework, a search was conducted on three databases (Scopus, PubMed, Web of Science), yielding 38 studies that met the following inclusion criteria: (1) focusing on parents of ASD children, (2) conducted in the SEA region, and (3) articles, excluding systematic and meta-analyses. Of the 38 studies, 24 were from Malaysia, 9 from Singapore, 3 from the Philippines, 1 from Indonesia, and 1 from Vietnam. No articles were found for Brunei, Burma, Myanmar, Cambodia, Timor-Leste, Laos and Thailand. The focus, across the 38 studies, was primarily on the effects of the ASD child's therapies and interventions on parents, followed by parenting stress and quality of life (QOL). Employment-related factors were seen in sub-themes of five studies from Malaysia and Singapore. The review showed a limited focus on employment-related concerns amongst working parents with ASD children within the SEA region. The study's limitations include the lack of studies from other SEA countries such as Brunei, Burma, Myanmar, Cambodia, Timor-Leste, Laos, and Thailand. It is suggested that future research should focus on work-related factors for this underrepresented population while considering the roles of individual, gender, cultural, and religious factors.

STRATEGIC IMPORTANCE OF ANCIENT INDIAN MARITIME POWER

India is a peninsular country bounded by the lofty Himalayas in the north, is surrounded by oceans and seas on three sides and has a 7,517 km long coastline. The Indian Ocean engulfs the country in its South. It has recently re-emerged as a sphere of power politics in International Relations. The following slok of Vishnu Purana illustrates the Geo-Strategic importance of Bharat.उत्तरं यत् समुद्रस्य हिमाद्रेश्चैव दक्षिणम् |वर्षं तद् भारतं नाम भारती यत्र सन्ततिः || विष्णु पुराण २.३.१The country that lies north of the ocean and south of the snowy mountains is called Bhāratam, there dwells the descendants of Bharat.China is in India’s backyard, an expansionist and imperialist power challenging the aspects of maritime security in the region, and Pakistan is a hostile neighbour, it is high time that a comprehensive framework of India’s maritime security is developed. As an ancient civilisation, the country has a rich legacy of its naval prowess. The civilisational culture from the ancient land of Bharat spread worldwide, especially in Southeast Asian, African, Central Asian, and East Asian countries through the Indian Ocean. The Indian Ocean, therefore, is not merely a waterbody. Instead, it captures the essence of India’s religion and cultural wave, transcending even to the neighbouring countries. India's history, art, mythology and literature are replete with numerous instances of the importance of the Indian Ocean in the lives of the Indian people. The cultural depth of the Indian civilisation is as deep as the Indian Ocean. Therefore, this article argues about the strategic relevance of ancient India’s maritime diplomacy.

IDEOLOGICAL ASPECTS OF RUSSIA’S FOREIGN POLICY IN SOUTHEAST ASIA

After the collapse of the Soviet Union, foreign policy relations with the countries of Southeast Asia entered a state of crisis, which affected economic, political and cultural ties. The repeated visits of representatives of the Russian leadership are an indicator of the attention that the Russian leadership pays to issues of development and cooperation with the countries of the region. Since the creation of independent states in Southeast Asia, the ideological basis of the emerging cooperation, conventionally called at that time “the export of socialism”, has been important. The article attempts to consider the historical prerequisites that determined the nature of domestic foreign policy in Southeast Asia from the perspective of ideological aspects of foreign policy. Among the main ideological aspects of foreign policy today, the most relevant are ensuring multipolarity, mutual respect for sovereignty and observance of the basic principles of security of international cooperation, ensured by mutual initiatives aimed at reducing armaments, expanding demilitarization zones, and integrating the economies of the countries of the Southeast Asian region into the world. The author concludes that the modern content of cooperation based on mutual respect, the progressive development of cooperation in all areas, and strategic interaction will allow relations with the countries of the region to develop steadily in the future.

Growth performance of durian based on crop water requirement (ETc) using irrigation system

Water use for agricultural production in water scarcity regions requires precise irrigation water for sustainable irrigation management. The correct amount of irrigation water should be applied to ensure the survival of plants. Currently, farmers apply irrigation without considering the actual amount of the crop water requirement (ETc), which may lead to over or under-irrigation. These problems may cause water logging, crop stress, reduced yield and inefficient farm management. Durian (Durio zibethinus) is an important economic crop of Southeast Asian countries, including Thailand, Malaysia, and Indonesia. Lately, durian plantation has been increasing in Malaysia with innovative and sustainable approaches through irrigation or fertigation. The growth of durian is highly affected by water and nutrients given to the plants. This paper highlights the effect of precise irrigation through durian water requirement. Hence, this study aims to compare the difference in growth performance between existing practices (irrigation without ETc) and irrigation based on ETc. The study was conducted in the durian plantation at Sri Lalang, Kluang, Johor. There were two treatments tested on the durian, which are treatment 1 (T1) existing practice (irrigation without ETc) and treatment 2 (T2), irrigation based on ETc. The experimental design for this experiment is a Randomized Complete Block Design (RCBD) with four (4) blocks, and four trees for each treatment per block. The data collection includes the height of the tree, canopy width, girth’s diameter, node distance, leaf length and leaf weight. These data were analysed using ANOVA and LSD. Data was collected from April until November 2020. There was a significant difference in node distance from April until September. However, there were no significant differences for other growth parameters, suggesting precise crop water requirement can save water and minimize cost for the whole irrigation management.

Spatiotemporal analysis of imported and local dengue virus and cases in a metropolis in Southwestern China, 2013–2022

Dengue fever is a viral illness, mainly transmitted by Aedes aegypti and Aedes albopictus. With climate change and urbanisation, more urbanised areas are becoming suitable for the survival and reproduction of dengue vector, consequently are becoming suitable for dengue transmission in China. Chongqing, a metropolis in southwestern China, has recently been hit by imported and local dengue fever, experiencing its first local outbreak in 2019. However, the genetic evolution dynamics of dengue viruses and the spatiotemporal patterns of imported and local dengue cases have not yet been elucidated. Hence, this study implemented phylogenetic analyses using genomic data of dengue viruses in 2019 and 2023 and a spatiotemporal analysis of dengue cases collected from 2013 to 2022. We sequenced a total of 15 nucleotide sequences of E genes. The dengue viruses formed separate clusters and were genetically related to those from Guangdong Province, China, and countries in Southeast Asia, including Laos, Thailand, Myanmar and Cambodia. Chongqing experienced a dengue outbreak in 2019 when 168 imported and 1,243 local cases were reported, mainly in September and October. Few cases were reported in 2013–2018, and only six were imported from 2020 to 2022 due to the COVID-19 lockdowns. Our findings suggest that dengue prevention in Chongqing should focus on domestic and overseas population mobility, especially in the Yubei and Wanzhou districts, where airports and railway stations are located, and the period between August and October when dengue outbreaks occur in endemic regions. Moreover, continuous vector monitoring should be implemented, especially during August–October, which would be useful for controlling the Aedes mosquitoes. This study is significant for defining Chongqing's appropriate dengue prevention and control strategies.

The impacts of lockdown policies on trade margins in the Philippines

The Philippines was among the most infected countries in Southeast Asia at the onset of the COVID-19 outbreak. This study analyzes how the export and import trade margins (extensive and intensive) of the Philippines were affected by the lockdown policies of trading partners. Using a quarterly series of product-by-country data for 20 quarters (quarter one of 2018-quarter four of 2022) and an event-study design, the paper shows that lockdown measures did not affect or mildly affected the intensive margin of exports and the import margins. Instead, the extensive margin of exports was most affected. It declined by 27% in the first quarter and by an average of 46% between the fifth and eleventh quarters of the lockdown. This was largely influenced by the closure of workplaces, stay-home requirements and controls on international travel. Export and import margins of intermediate goods were more resilient to the lockdown shocks. Overall, preventing disruptions in the supply chain networks can help countries adjust better and contribute to a speedy recovery and possible resilience to future shocks.

Probing the Nexus Effect of CO2 Emissions, Fossil Fuels, Energy Imports and Economic Growth on Renewable Energy Consumption in OIC Member Countries in Southeast Asia: Evidence from Panel Data Estimations

In recent years, the role of renewable energy sources has increased in the amount of energy consumed worldwide. Much remains unknown about the components that influence renewable energy consumption. This article addresses this issue for the Southeast Asian countries that are members of the Organization of Islamic Cooperation (OIC): Indonesia, Malaysia and Brunei Darussalam. Besides having major energy resources, the region is well suited for renewable energy development as it can measure the effects of carbon dioxide emissions, fossil fuels, energy imports, and economic growth. In this study, we found that there is no statistically significant difference in renewable energy consumption in previous years; economic growth and concurrent increases in carbon dioxide and fossil fuel emissions do not have a positive impact on renewable energy use in the OIC region of Southeast Asia; and the impact of energy imports has a significant impact on the consumption of renewable energy. In addition, how the findings of this study impact policy is discussed.

Bone turnover markers reference database in five Southeast Asian countries

Osteoporosis is highly prevalent, particularly in developing countries. However, bone turnover marker reference ranges for management of osteoporosis in Asian population are yet to be explored and established. Thus, this study aims to develop a regional bone turnover markers (BTMs) reference database by combining country-specific reference database from five ASEAN countries: Malaysia, the Philippines, Singapore, Thailand, and Vietnam. We established a healthy reference population of 746 healthy premenopausal women aged 20 to 44 years old. Serum Procollagen 1 N-Terminal Propeptide (P1NP), Osteocalcin (OC), and Beta-Crosslaps (CTX) concentrations were measured using an automated immunoassay analyzer system, the cobas® modular analyzer systems (Roche Diagnostic Gmbh). The reference interval was defined as the central 95 % range. The estimated reference interval for CTX was 128 to 811 ng/L, OC was 9.0 to 33.0 μg/L, and for P1NP, the range was 22.8 to 96.5 μg/L. Comparison across countries showed that Singaporeans had the highest levels of median CTX along with Thais and Filipinos, who had significantly higher levels of P1NP and OC. Exploratory analysis on the associations with age showed that BTMs decreased with increasing age at 20 to 29 years old and plateaued after 30 years old. When excluding participants in their 20s, the reference interval estimated were CTX: 117–678 ng/L, P1NP: 21.6–85.8 μg/L and OC: 3.5–27.0 μg/L respectively. To the best of our knowledge, this is the first study to report BTMs reference intervals based on a healthy premenopausal Southeast Asian population which will contribute to the appropriate assessment and monitoring of bone turnover rate in the evaluation and management of osteoporosis in the Southeast Asian region. Lay summaryOsteoporosis is a common health issue, especially in developing countries. However, there is a lack of information on bone health markers specific to the Southeast Asian population. This study aimed to fill this gap by creating a reference database for bone turnover markers (BTMs) in Southeast Asian countries, including Malaysia, the Philippines, Singapore, Thailand, and Vietnam. The researchers studied 746 healthy women aged 20 to 44 years and measured blood markers related to bone health. The reference interval, representing the normal range, was determined. For example, the normal range for CTX was found to be 128 to 811 ng/L, for Osteocalcin was 9.0 to 33.0 μg/L, and for P1NP, the range was 22.8 to 96.5 μg/L. When excluding participants in their 20s, the reference intervals estimated were CTX: 117–678 ng/L, P1NP: 21.6–85.8 μg/L and OC: 3.5–27.0 μg/L respectively. Comparing the results across countries, Singaporeans, Thais, and Filipinos showed variations in their biochemical bone marker levels. Additionally, the study observed changes in the levels with age, with a decrease in BTMs observed after the age of 30. This groundbreaking study provides the first-ever reference intervals for BTMs in a healthy premenopausal Southeast Asian population. These findings will help in the proper assessment and monitoring of bone health, contributing to the management of osteoporosis in the Southeast Asian region.

Affiliate Stigma, Resilience and Quality of Life among Parents of Children with Autism Spectrum Disorder in Two Public Hospitals in Kelantan, Malaysia.

Often, the indirect impact of autism spectrum disorder (ASD) presents the family with significant challenges. One of these challenges is affiliate stigma due to parental affiliation with their child. This study aimed to explore affiliate stigma, resilience and quality of life (QoL) among parents of children with ASD. Cross-sectional study of 144 parents of children with ASD were recruited from two main tertiary hospitals in Kelantan, Malaysia, a developing country in Southeast Asia. Pearson correlation was used to examine the relationship between parental affiliate stigma, resilience and QoL. Simple and multiple linear regression analyses were used to identify the significant associated factors of affiliate stigma, resilience and QoL. Correlational analyses revealed that perceived affiliate stigma demonstrated an inverse relationship with resilience and QoL. Additionally, resilience had a positive relationship with QoL. Regression analyses revealed that the father's employment status, the mother's level of education, having a disability card, the child's age at ASD diagnosis, comorbidities of the child and ASD severity perceived by parents were associated with parental affiliate stigma, resilience and QoL. Study findings highlight the contribution of socio-demographic characteristics of children with ASD and their families in the determination of affiliate stigma, resilience and QoL.

Public Administration Ethics Education to Build Anti-Corruption Integrity among Students of SMP N 13 Padang

The high level of corruption, which has become a pathology in developing countries, especially Indonesia, is evidenced by the 2022 international transparency data, which scored 34/100 and ranked 110 out of 180 surveyed countries. Indonesia ranks as the 5th most corrupt country in Southeast Asia. With these results, Indonesia has only been able to increase its Corruption Perception Index (CPI) score by 2 points from 32 over the past decade since 2012. Despite Law No. 20 of 2001's eradication of corruption, which covers various aspects, related to anti-corruption efforts, including education and anti-corruption socialization, this pathology remains unresolved. Therefore, a strong foundation is needed, especially among the younger generation as the nation's future leaders, by strengthening students' character regarding integrity and courage against corruption. This community engagement used socialization, interviews with school members, and participatory observation within the school environment. The concept of public administration ethics serves as the basis for this activity. The results showed that anti-corruption education through the perspective of public administration at SMP N 13 Padang plays a significant role in shaping students' integrity and courage in combating corruption. As adolescents, students are in the process of forming moral values and behaviors. Thus, anti-corruption education interventions can significantly impact shaping their character. Students improved their understanding of corruption and developed a more courageous attitude and strong integrity. The results provided valuable insights and a foundation for further improvement in anti-corruption education in middle schools.

Empirical Analysis on Economic Sustainable of Rice Rain-Fed Area in Rural Cambodia

This paper investigates the economic sustainability of Cambodian rural rice farmers. Rice in Cambodia is a stable crop just as in many other Southeast Asian countries. The rice plants not only provide food to people but also a source of feed for livestock. Based on survey about of 6 districts of the rural household in Battambang of Cambodia, a total 204 rice farmers were interviewed and multiple regression models was applied using the method of Ordinary Least Squares (OLS) to determine the factors affecting the Crop-livestock farmers’ disposable income. The study aggregated the livestock of 3 species including cattle, pig and chicken in cattle unit standard known as Livestock Unit (LU). The result of the empirical analysis shows that many household demography factors as well as the socioeconomic factors influences the disposable income. The findings in the study provide an insight to the government and extension offices on effective development of economic sustainability of rice farming and livestock production system in the regions; investing more in public animal healthcare; ensure stable market prices for both rice and livestock, paying more attention on the factors limiting income in particular to poorer provinces and districts. Provide irrigation facilities accompanied with high technological varieties to encourage the double or even triple rice seasons. In addition, government (especially the ministry of agriculture) should embark on technological transfer among provinces and countries with successful agricultural system, orient farmers on the potential benefits of crop-livestock farming, provide training ground and scheme to local farmers.

Brackish Water Phytodesalination by the Euhalophyte Sesuvium portulacastrum

In the Middle East and North Africa as well as in numerous countries in South America and Southeast Asia, water scarcity is a real concern. Therefore, water desalination has become a key solution and an important source of freshwater production. Solar stills are used for water desalination but they require low depth of sea or brackish water and sufficient solar radiation to evaporate water. In this investigation, a phytodesalinator is presented for the first time. The halophyte used in this work is Sesuvium portulacastrum L., a heat-tolerant euhalophyte. The presented phytodesalinator can replace basic solar stills during cold seasons if there is sufficient sunlight to ensure the transpiration process in the plant. The euhalophyte S. portulacastrum was tested for its ability to desalinate reject brine as grown for two subsequent phytodesalination cycles. Several factors were found to affect the productivity of the phytodesalinator, in particular, solar radiation, phytodesalination duration, and plant density. Nevertheless, it exhibited an average productivity of 2.44 kg/m2/d and showed several advantages in comparison with basic solar stills.

Effect of external corporate factors on takaful performance

PurposeThis study examines the impact of external corporate factors (external auditors, insured satisfaction and corporate social responsibility) on the performance (ROA, ROE, ROI) of takaful providers of distinguishable Muamalah contracts (wakalah and Hybrid).Design/methodology/approachThe full sample includes 30 Takaful insurance companies listed in Southeast Asia (SEA) and Gulf Cooperation Council (GCC) countries over the period 2011–2021. We use the FGLS method for data analysis.FindingsOur results reveal that Takaful insurance, which holds one of the Big Four with qualified Shariah members as external auditors, leads to improved performance (ROA, ROE and ROI). In addition, our findings show that Takaful insurance should be concerned with insured satisfaction to determine its success and generate higher performance for both the wakalah and hybrid contracts (ROA, ROE and ROI). Furthermore, Corporate Social Responsibility is considered a source of efficiency that enhances Takaful’s performance for the two types of wakalah and hybrid models (ROA, ROE and ROI).Practical implicationsSome suggestions may be useful for Takaful insurance regulatory authorities to intensify CSR activities, hold one of the Big Four as an external auditor and realize insured satisfaction.Originality/valueThis study highlights that it is beneficial for policymakers, insurers and investors to explore external factors that influence financial performance (return on assets, ROA; return on equity, ROE; return on investment,) in the Takaful insurance market, which uses wakalah and hybrid contracts.

Relationship of Protest Activity with the Social Tension Dynamics in the South-East Asian Countries

The article is devoted to testing the method of forecasting major conflicts in countries of Southeast Asia. The method is based on the assumption of the social tension growth in the last years before the event. Tensions are not definitely linked to protest activity. They contribute to socio-political or ethno-political mobilization, which can lead to the destabilization of society. Therefore, with high rates of tension growth in the country, the probability of serious conflicts increases. For a quantitative assessment of the social tension in the countries of Southeast Asia, the most relevant statistical indicator is the suicides number. We assume that the five-year growth rate of the tension indicator (the level of conflict) exceeding a certain threshold value indicates the possibility of major protests. The calculations carried out for the Southeast Asian countries made it possible to estimate the probability of major conflicts with an accuracy close to the machine learning methods. The use of the proposed indicator for the analysis of socio-political processes in the countries of Southeast Asia made it possible to explain their similarities in countries with different economic, demographic, political and cultural characteristics, i. e. obtain additional information characterizing in these countries the stability or conflict risk.

Trends and drivers of income inequality in the Philippines, Thailand, and Viet Nam since the early 2000s: A decomposition analysis

Income inequality has moderated in the Philippines, Thailand, and Viet Nam, three middle income countries in Southeast Asia, over the past two decades, with multiple factors at play. In each country, wage, nonfarm business income, and overseas remittance concentrations declined as less well-off households increasingly engaged in better-paying activities. In Thailand and Viet Nam, transfer incomes became more pro-poor and better targeted. Major contributors to lower income inequality also included a narrowing in regional disparity and a reduction in the urban-rural income gap, and, in the Philippines and Thailand, a fall in the education premium. This recent trend of moderating income inequality might be the combined outcome of rising income opportunities generated by structural transformation and government policies promoting social inclusion. Nonetheless, income inequality remains high, especially in the Philippines and Thailand. More policy efforts are needed to make growth more inclusive.

High genetic diversity in anguillid glass eels across three Southeast Asian countries revealed through mitochondrial DNA D-loop sequences, with notes on population structure

Understanding the genetic diversity and population structure of anguillid eels is crucial for effective management. In this study, we used the mitochondrial DNA (mtDNA) D-loop marker to identify anguillid glass eels and assessed their genetic diversity across six sampling sites spanning three Southeast Asian countries. We also examined the population structures of Anguilla marmorata and A. celebesensis. We validated nine distinct species and subspecies of anguillid eels from 465 specimens collected in Indonesia (n = 246), the Philippines (n = 119), and Vietnam (n = 100). High gene diversities were observed across the species, ranging from 0.979 (A. celebesensis) to 1.000 (A. bicolor bicolor, A. marmorata, and A. interioris). Correspondingly, nucleotide diversity values were relatively low, varying from 0.036 (A. marmorata) to 0.057 (A. interioris). A. marmorata (n = 162) displayed a broad distribution, being observed across all six sites, with a significant yet low average fixation index of 0.05755. Pairwise comparisons of FST values between Cimandiri and other locations (except for Cagayan) were relatively high and statistically significant (p < 0.01), indicating significant genetic differentiation of Cimandiri samples compared to most locations in this study. On the other hand, A. celebesensis (n = 110), exhibited a non-significant and low fixation index (0.007), indicating no genetic differentiation in samples from Poso and Poigar Rivers, Indonesia. Our findings highlight the essential need for coordinated management strategies among regions that share common stocks. Additionally, this study underscores the efficacy of the mtDNA D-loop in precisely identifying glass eel species/subspecies and elucidating the genetic diversity and population structure of tropical anguillid eels.

Functional characterization of sex pheromone receptors PflaOR29 and PflaOR44 involved in the chemoreception of a diurnal moth, Phauda flammans (Walker) (Lepidoptera: Phaudidae)

Recognition of sex pheromones released by heterosexual moths via sex pheromone receptors is key for establishing mating connections in moths. The day-flying moth Phauda flammans is an oligophagous pest in southern cities of China and Southeast Asian countries. Our previous study reported that male P. flammans can be attracted to two sex pheromone compounds [Z-9-hexadecenal and (Z, Z, Z)-9,12,15-octadecadienal] released by females in the field; however, the mechanism of olfactory recognition is not clear. In this study, two sex pheromone receptor genes (PflaOR29 and PflaOR44) were cloned. Among the different tissues, both PflaOR29 and PflaOR44 were highly expressed in the antennae of mated male adults. At different developmental stages, the expression levels of PflaOR29 and PflaOR44 were significantly greater in mated male adults than other stages. The fluorescence signals of PflaOR29 and PflaOR44 were mostly distributed on the dorsal side of the antennae, with a large number of trichoid sensilla. The results of the gene function of PflaOR29 and PflaOR44 based on a Drosophila empty neuron heterologous expression system indicated that PflaOR29 strongly responded to (Z, Z, Z)-9,12,15-octadecadienal but not to Z-9-hexadecenal, whereas PflaOR44 did not respond to the two sex pheromones. Our findings clarify the sex pheromone receptor gene corresponding to (Z, Z, Z)-9,12,15-octadecatrienal. These results provide essential information for analyzing the mechanism of sexual communication in diurnal moths and for identifying target genes for the development of efficient attractants.