Description and Molecular Differentiation of a New Skrjabinoptera (Nematode: Physalopteridae) from Eutropis macularia (Sauria: Scincidae) in North-Central Vietnam

Members of the genus Cinnamomum (Lauraceae) have aromatic volatiles in their leaves and bark and some species are commercially important herbs and spices. In this work, the essential oils from five species of Cinnamomum (C. damhaensis, C. longipetiolatum, C. ovatum, C. polyadelphum and C. tonkinense) growing wild in north central Vietnam were obtained by hydrodistillation, analyzed by gas chromatography and screened for antimicrobial and mosquito larvicidal activity. The leaf essential oil of C. tonkinense, rich in β-phellandrene (23.1%) and linalool (32.2%), showed excellent antimicrobial activity (MIC of 32 μg/mL against Enterococcus faecalis and Candida albicans) and larvicidal activity (24 h LC50 of 17.4 μg/mL on Aedes aegypti and 14.1 μg/mL against Culex quinquefasciatus). Cinnamomum polyadelphum leaf essential oil also showed notable antimicrobial activity against Gram-positive bacteria and mosquito larvicidal activity, attributable to relatively high concentrations of neral (11.7%) and geranial (16.6%). Thus, members of the genus Cinnamomum from Vietnam have shown promise as antimicrobial agents and as potential vector control agents for mosquitoes.

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Forest Cover Change, Households’ Livelihoods, Trade-Offs, and Constraints Associated with Plantation Forests in Poor Upland-Rural Landscapes: Evidence from North Central Vietnam

Forests ◽

10.3390/f11050548 ◽

2020 ◽

Vol 11 (5) ◽

pp. 548 ◽

Cited By ~ 3

Author(s):

Quy Van Khuc ◽

Tuyet-Anh T. Le ◽

Trung H. Nguyen ◽

Duy Nong ◽

Bao Quang Tran ◽

...

Keyword(s):

Household Income ◽

Shifting Cultivation ◽

Current Status ◽

Plantation Forest ◽

North Central ◽

Rural Landscapes ◽

Plantation Forests ◽

Trade Offs ◽

Central Vietnam ◽

Total Household Income

Vietnam’s forests have experienced a notable transformation over the past 20 years from net deforestation to reforestation and expanding forests. Continued reforestation that aims to achieve further economic and environmental benefits remains a national priority and strategy. We explore the current status of plantation forests and highlight possible means to facilitate their expansion in the uplands of Vietnam. We employ mixed method triangulation to empirically explore plantation forests and their economic role in household livelihood, to quantify trade-offs between plantation forests and shifting cultivation, and to assess the constraints on plantation forest expansion in Nghe An province, north-central Vietnam. Results show that forest in the study area expanded by 406,000 ha (71.1%) between 1990 and 2016. Plantation forests increased by nearly 500% (from 32,000 ha to 190,000 ha), while natural forests expanded by 48.1% (from 538,000 ha to 797,000 ha). Plantation forests contributed an average of 35.1 percent of total household income in wealthier households and 27.9 percent of income in poor households. Switching from shifting cultivation to plantation forests would increase total household income and average carbon stock but decrease food provision. Total Economic Value would be higher for plantation forest scenarios if increased carbon stocks in plantations can be monetized. This carbon income might drive conversion of shifting cultivation to plantation forests. Constraints on further expansion of plantation forest are low external cooperation, education, market stability, and agroforestry extension services. Our empirical results inform national plantation forest development, sustainable upland livelihood development, and climate change mitigation programs to ultimately facilitate forest transition and improve the resilience and sustainability of socio-ecological systems.

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Vulnerability to Natural Disaster and Welfare Effect: A Case Study of Flood Risk in Vietnam’s North Central Region

Journal of Asian and African Studies ◽

10.1177/0021909621993499 ◽

2021 ◽

pp. 002190962199349

Author(s):

Manh-Hung Nguyen ◽

Dung P Le ◽

Thang T Vo

Keyword(s):

Flood Risk ◽

Sampling Method ◽

Household Survey ◽

North Central ◽

Household Level ◽

Central Vietnam ◽

Housing Costs ◽

Household Vulnerability ◽

The Impact

This article investigates the impact of flood risk on vulnerability and welfare at the household level in Vietnam. The analytical sample is taken from a household survey conducted in a north central Vietnam community through a three-stage stratified random sampling method. The propensity score matching approach is employed to compare various welfare indicators between flooded and non-flooded households. This study finds that flooding results in significant income losses and imposes higher costs of living, especially housing costs. The two types of households are vulnerable, implying that other natural disasters or socio-economic disadvantages may have adverse effects on households’ livelihoods. The insignificant effect of floods on vulnerability indicates that the flooded households can cope with floods to some extent. However, contrary to family support, formal coping strategies are insufficient or ineffective at reducing household vulnerability to floods.

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Spatial distribution and association patterns in a tropical evergreen broad-leaved forest of north-central Vietnam

Journal of Vegetation Science ◽

10.1111/jvs.12361 ◽

2015 ◽

Vol 27 (2) ◽

pp. 318-327 ◽

Cited By ~ 21

Author(s):

Hong Hai Nguyen ◽

Jaime Uria-Diez ◽

Kerstin Wiegand

Keyword(s):

Spatial Distribution ◽

Association Patterns ◽

North Central ◽

Broad Leaved Forest ◽

Central Vietnam ◽

Leaved Forest

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Diversity and Distribution of Rice Blast (Pyricularia oryzae Cavara) Races in Vietnam

Plant Disease ◽

10.1094/pdis-05-19-1008-re ◽

2020 ◽

Vol 104 (2) ◽

pp. 381-387 ◽

Cited By ~ 1

Author(s):

Nguyen T. M. Nguyet ◽

Hoang H. Long ◽

Nguyen B. Ngoc ◽

Nguyen T Nhai ◽

Nguyen T. T. Thuy ◽

...

Keyword(s):

Resistance Genes ◽

Rice Blast ◽

Pyricularia Oryzae ◽

Red River ◽

Red River Delta ◽

North Central ◽

South Central ◽

Central Vietnam ◽

Differential Varieties ◽

Reaction Patterns

A total of 239 isolates of blast (Pyricularia oryzae Cavara) collected from northern and central Vietnam showed a wide variation in pathogenicity based on the reaction patterns to 25 differential varieties (DVs) harboring 23 resistance genes and susceptible cultivar Lijiangxintuanheigu (LTH). The frequencies of isolates virulent toward DVs for Pish, Pik-m, Pi1, Pik-h, Pik, Pik-p, Pi7(t), Pi9(t), Piz-5, Pita-2, and Pita were low, but they were high for DVs for Pib, Pit, Pia, Pii, Pi3, Pi5(t), Pik-s, Piz, Piz-t, Pi12(t), Pi19(t), and Pi20(t). Isolates were classified into three cluster groups Ia, Ib, and II based on reaction patterns to DVs and LTH. The frequencies of isolates virulent toward 11 DVs for Pik-m, Pi1, Pik-h, Pik, Pik-p, Pi7(t), Pi9(t), Piz, Piz-5, Pita-2, and Pita in cluster II and DV for Piz-t were higher and lower than those of Ia and Ib, respectively. The frequencies to DVs for Pii, Pi3, Pi5(t), and Piz-t were different between clusters Ia and Ib. Clusters Ia and Ib were distributed with similar frequencies in the northeast, north central, and south central coast regions, but the frequencies among three cluster groups in the Red River Delta and northwest regions were different. This means that the blast races in these two regions were different from the others. Overall, the blast isolates were categorized into 153 races. Among them, 26 were selected as a set of standard differential blast isolates for characterizing 23 resistance genes and developing a differential system in Vietnam.

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