Ethnobotany and phytochemistry of plants used to treat musculoskeletal disorders among Skaw Karen, Thailand.

CONTEXT: Musculoskeletal system disorders (MSD) are prevalent around the world affecting the health of people, especially farmers who work hard in the field. Karen farmers use many medicinal plants to treat MSD. OBJECTIVE: This study collects traditional plant-based remedies used by the Skaw Karen to treat MSD and evaluates their active phytochemical compounds. MATERIALS AND METHODS: The ethnobotanical study was conducted in six Karen villages in Chiang Mai province using semi-structured interviews were of 120 informants. The data were analyzed using ethnobotanical indices including use values (UV), choice value (CV), and informant consensus factor (ICF). Consequently, the 20 most important species, according to the indices, were selected for phytochemical analysis using LC-MS/MS. RESULTS: A total of 3731 use reports were obtained for 139 species used in MSD treatment. The most common ailments treated with those plants were muscular pain. A total of 172 high-potential active compounds for MSD treatment were identified. Most of them were flavonoids, terpenoids, alkaloids, and steroids. The prevalent phytochemical compounds related to treat MSD were 9-hydroxycalabaxanthone, dihydrovaltrate, morroniside, isoacteoside, lithocholic acid, pomiferin, cucurbitacin E, leonuriside A, liriodendrin, and physalin E. Sambucus javanica Reinw. ex Blume (Adoxaceae), Betula alnoides Buch.-Ham. ex D.Don (Betulaceae), Blumea balsamifera (L.) DC. (Asteraceae), Plantago major L. (Plantaginaceae) and Flacourtia jangomas (Lour.) Raeusch. (Salicaceae) all had high ethnobotanical index values and many active compounds. DISCUSSION AND CONCLUSIONS: This study provides valuable information, demonstrating low-cost medicine plants that are locally available. It is a choice of treatment for people living in remote areas.

A Nutrition-Sensitive Agriculture Initiative in Ethnic Communities of Northern Thailand: Local Perspectives and Future Prospects.

BACKGROUND: Nutrition-sensitive agriculture (NSA) interventions can contribute to improved food security and household dietary diversity. As well as undertaking trials, contextual factors that influence sustainability need to be scoped. OBJECTIVE: To explore locals' views of an NSA initiative, designed to improve food security and reduce malnutrition in children younger than 5 years, scoping future prospects 6 months after the conclusion of the trial. METHODS: The initiative that was formally trialed over 6 months (November 2014 to April 2015) entailed keeping hens and home gardens. It occurred in the ethnic hill tribes of northern Thailand. In November 2015, 20 in-depth interviews were undertaken with villagers who had been involved in the initiative. Dialogue occurred in Thai with assistance of a translator and was recorded, transcribed, and translated to English. A detailed thematic analysis was undertaken. RESULTS: Eggs produced by the hens were appreciated and fed to children, and the message of providing children with an egg a day was widely remembered. Subsequently, the hens ceased laying or died. The home gardens had seasonal scarcity of water. Less visible, but fundamental, women lacked time for these activities due to heavy burdens of farm labor. CONCLUSION: Keeping hens has potential to become a sustainable activity. Home gardens need water infrastructure to be viable. Women do not necessarily have spare capacity for such initiatives. The required labor needs deliberation by villagers.

Nutrient and Mineral Compositions of Wild Leafy Vegetables of the Karen and Lawa Communities in Thailand.

Wild food plants are commonly used in the traditional diets of indigenous people in many parts of the world, including northern Thailand. The potential contribution of wild food plants to the nutrition of the Karen and Lawa communities remains poorly understood. Wild food plants, with a focus on leafy vegetables, were ranked by the Cultural Food Significance Index (CFSI) based on semi-structured interviews. Twelve wild plant species were highly mentioned and widely consumed. The importance of the wild vegetables was mainly related to taste, availability, and multifunctionality of the species. Their contents of proximate and minerals (P, K, Na, Ca, Mg, Fe, Mn, Zn, and Cu) were analyzed using standard methods. The proximate contents were comparable to most domesticated vegetables. The contents of Mg (104 mg/100 g FW), Fe (11 mg/100 g FW), and Zn (19 mg/100 g FW) in the wild leafy vegetables were high enough to cover the daily recommended dietary allowances of adults (19-50 years), whereas a few species showed Mn contents higher than the tolerable upper intake level (>11 mg/100 g edible part). The wild leafy vegetables, therefore, are good sources of minerals and we recommend their continued usage by indigenous people. Further research on these wild leafy vegetables' contents of antioxidants, vitamins, heavy metals, anti-nutrient factors, and food safety is recommended.

Medicinal Plants for Treating Musculoskeletal Disorders among Karen in Thailand.

Millions of people suffer from Musculoskeletal System Disorders (MSDs), including Karen people who work hard in the fields for their subsistence and have done so for generations. This has forced the Karen to use many medicinal plants to treat MSDs. We gathered data from 15 original references covering 27 Karen communities and we document 461 reports of the use of 175 species for treating MSDs among the Karen people in Thailand. The data were analyzed by calculating use values (UV), relative frequency of citation (RFC) and informant consensus factor (ICF). Many use reports and species were from Leguminosae and Zingiberaceae. Roots and leaves were the most used parts, while the preferred preparation methods were decoction and burning. Oral ingestion was the most common form of administration. The most common ailment was muscle pain. Sambucus javanica and Plantago major were the most important species because they had the highest and second-highest values for both UV and RFC, respectively. This study revealed that the Karen people in Thailand use various medicinal plants to treat MSDs. These are the main resources for the further development of inexpensive treatments of MSDs that would benefit not only the Karen, but all people who suffer from MSD.

Traditional Uses of Leguminosae among the Karen in Thailand.

Leguminosae (legumes) are one of the largest plant families. They are widely used for a variety of purposes by people around the world and include many important cultivated economic food crops. On local scales, legumes are commonly used by various ethnic groups. However, the data are incomplete and scattered, not least in Thailand. We found that species of legumes were important in Karen communities, so we decided to investigate in detail the traditional knowledge of legumes on a local scale among Karen people in northern Thailand. We interviewed six herbalists and eighty-four nonherbalist informants in three Karen villages in Chiang Mai province about their use of legumes, and about the local names for the species, using semistructured interviews. A total of 83 legumes species (in 45 genera) had 4443 use reports. Five of the 83 legume species had not been reported previously as used in Thailand. Most Karen use reports (43%) of legumes were for food, medicine (36%), and materials (8%), but in term of species more legumes (68 species) were used for medicine than for food (53 species). The legume genera with most used species were Crotalaria and Flemingia each with six species. The most important species are Tamarindus indica (CI = 3.38), Senegalia rugata (CI = 2.39), Glycine max (CI = 1.27) respectively.

Exotic Plants Used by the Hmong in Thailand.

Exotic species are an integral part of the plants used by many ethnic groups, but they usually receive little attention and have been considered alien to the ethnobotanical data. Here, we analyze the plants used by Thai Hmong refugees that are not native to their current habitats in Thailand. We attempt to understand the sources of this knowledge. Do people maintain the original traditional knowledge related to exotic species when they migrate to a new region, or does new knowledge originate from acculturation? We interviewed 16 specialist Hmong informants in Nan province, Thailand, about their traditional knowledge of 69 exotic species used. Acquisition of this knowledge has a long history; several species are the same as plants used by the Hmong in China and other countries, others are globally useful species which have become part of the pool of species that the Hmong have developed local knowledge about. However, migration also involves the integration of local knowledge from other cultures, and also adapts them to function in urban settings. This includes using closely related exotic taxa that replace some of the species they used in their original homelands. The migrants' traditional knowledge in their new habitats is more complicated and also involves the development of local knowledge that is entirely new.

Genetic assessment of three Fagaceae species in forest restoration trials.

Restoring isolated patches of forest ecosystems in degraded landscapes could potentially lead to genetic loss and inbreeding. Therefore, this study determined the occurrence of genetic diversity among the tree species Castanopsis tribuloides, C. calathiformis, and Lithocarpus polystachyus all of which were proven previously to be effective native tree species in the restoration of upland evergreen forests in northern Thailand when using the seed sample collection method. We tested our hypothesis as to whether the genetic diversity of a plant population that had been planted from the seeds of 4-6 adult trees would be lower and whether incidences of fixation index (Fis) would be higher among the second generation seedlings of these three Fagaceae species in isolated forest restoration trial plots. Microsatellite primers were selected from the entire genome sequence of C. tribuloides and the genetic sequences of C. tribuloides, L. polystachyus, and C. calathiformis were analyzed. Our results indicated a high degree of genetic diversity (He) in C. tribuloides (0.736) and C. calathiformis (0.481); however, a low level of genetic diversity was observed in L. polystachyus (0.281) within the restored forest. The fixation index for the second generation of L. polystachyus and C. calathiformis in the restored forest showed evidence of inbreeding. These results imply the efficiency of the seed sample collection method and verify that it does not reduce the level of genetic diversity in C. tribuloides and C. calathiformis. However, it may result in incidences of an inbreeding phenomena, suggesting the need to increase the number of adult trees used at the seed collection stage.

Medicinal plants in homegardens of four ethnic groups in Thailand.

ETHNOPHARMACOLOGICAL RELEVANCE: Homegardens are important habitats for medicinal plants and traditional knowledge, especially among indigenous groups in remote areas. In homegardens, medicinal plants and traditional knowledge are well conserved through human management and ease of access. AIM OF THE STUDY: To understand the drivers of diversity and the composition of homegardens with focus on medicinal plants, including exotic species, and their uses. We compare the homegardens of four ethnic groups in northern Thailand (Thai Yuan, Lahu, Karen, and Lisu). METHODS: We inventoried all medicinal species in 195 homegardens from four villages belonging to the four ethnic groups. The owners were asked to point out all useful species in their homegardens. For any medicinal species, they were then interviewed about their main and secondary uses, medicinal properties, plant part used, preparation methods, and route of administrations. RESULTS: We recorded 95 medicinal homegarden plant species ranging from 20-59 species per village and ethnic group. Most of the medicinal plants had a primary use as food plants, which demonstrated the close relationship between local food and medicine in the lives of these ethnic groups. Many of the medicinal plants were also used as food additives, ornamentals, or materials, showing that medicinal plants are not an exclusive category in the homegardens. The number of homegarden plants varied almost four-fold from 58 species in one village to 211 in the most species rich village. The number of medicinal homegarden plants varied accordingly from 20 to 59 in the poorest and the richest villages. Five medicinal species were found in all villages, but 70% of the medicinal plants were found in only one village. Infection & infestation, Nutritional disorders, and Digestive system disorders were the three most important medicinal use categories for plants in the homegardens, and all three categories were found in most of the studied homegardens. Of the 95 species with medicinal uses, 26 (27%) were exotic, which shows that local people amplify the spectrum of alternative ways to treat their illnesses. CONCLUSION: Homegardens are an important source of ethnomedicinal species and knowledge. These species are beneficial for treating acute and common ailments; they are easy to access and can be prepared by simple methods, which are suitable for treating disorders, such as infections or any digestive system ailments. Medicinal plants in homegardens have been important in improving health, at least, at the family level.

Stunting, dietary diversity and household food insecurity among children under 5 years in ethnic communities of northern Thailand.

BACKGROUND: The aim of this study was to describe stunting in infants and young children in the ethnic communities of northern Thailand and to explore associations with dietary diversity and household factors including food security. METHODS: A cross-sectional survey of households with children under 5 years from eight villages. Adult respondents provided information on foods consumed by each child and details of the household. Heights and weights of children were measured. RESULTS: Adults from 172 households and 208 children participated. Overall, 38% of children were stunted. Exclusive breastfeeding was rare, but the proportion consuming breastmilk at 24 months (75%) was high. Few children (7%) aged 6-11 months met minimum dietary diversity. Stunted children were less likely than non-stunted children to meet minimum dietary diversity (63 versus 82%). Widespread food insecurity did not discriminate between stunted and non-stunted children. Stunting was elevated when households had little land and few animals. CONCLUSIONS: Stunting was widespread in children under 5 years of age, in part reflecting poor dietary diversity, especially at age 6-11 months. Stunting was worst in households with least assets. Small increases in land or animals, or equivalent resources, appear to be required to improve child nutrition in extremely poor families.

Health Workers' and Villagers' Perceptions of Young Child Health, Growth Monitoring, and the Role of the Health System in Remote Thailand.

BACKGROUND: In Thailand, despite widespread improvements in child nutrition, stunting is still highly prevalent among northern hill tribe children. OBJECTIVE: To understand how villagers and health workers (volunteers and officials) gauge health of children younger than 5 years, whether growth monitoring is salient, and the relationships of villagers with the health system in this remote location. METHODS: Qualitative research was undertaken with 8 hill tribe villages. A workshop on infant and young child health and nutrition was held with 8 village health volunteers, 2 per village, selected by a public health officer. In-depth interviews were conducted with 20 villagers and 2 volunteers who had children 0 to 5 years. Eight other health workers were also interviewed. All dialogue was conducted in Thai through bilingual facilitators and recorded, transcribed, and translated into English. Transcripts were coded and analyzed thematically within and across participant groups. RESULTS: Overall, villagers considered strength and independence of children to be hallmarks of health; the size of children featured rarely. Volunteers did not perceive local benefits of growth monitoring, and the extent of child malnutrition was unclear to them. Nutrition counseling was seldom mentioned by villagers or health workers. Across all accounts, and considering silences, relationships of villagers with the health system seemed fragile. CONCLUSION: Villagers understand child health in terms of functional abilities rather than size. Volunteer health workers in this remote location have limited resources and support. Together this helps explain why, against a background of poverty and food insecurity, growth monitoring does not translate to improvements in child nutrition.

Local perspectives and context in relation to feeding practices of children under 2 years in the mountain villages of northern Thailand.

OBJECTIVE: To gain an in-depth understanding of infant and young child feeding practices, accompanying beliefs and their sociocultural context in the Karen and Lua ethnic communities of northern Thailand. DESIGN: A two-day workshop and thirty in-depth interviews were undertaken in June 2014. Dialogue occurred with the assistance of translators and was recorded, transcribed and translated. A detailed thematic analysis was undertaken. SETTING: Northern Thai indigenous communities in which one-third of the children under 5 years of age are stunted. SUBJECTS: People with various roles in the local health system and twenty-six villagers who cared for infants and young children. RESULTS: Predominant breast-feeding was said to occur for 1 to 3 months but was not exclusive due to early introduction of water and/or rice. Exclusive breast-feeding for 6 months was impeded by the need for mothers to return to farming work, with the early introduction of solids enabling infants to be cared for by other family members. Low variety in complementary foods was typical during infancy, with few local foods having appropriate texture and special preparation of foods rarely described. A pervasive underlying issue is women's responsibility to labour and lack of time to care for their young children. Poverty and food insecurity also featured in participants' accounts. CONCLUSIONS: In combination, women's limited time to care, poverty and food insecurity are perpetuating poor nutrition of children in early life. Agricultural solutions that are being explored should also attend to the burden of work for women.

Development of 13 microsatellite markers for Castanopsis tribuloides (Fagaceae) using next-generation sequencing.

Catanopsis tribuloides is a climax tree species commonly distributed in evergreen forests and has been used to restore degraded areas in northern Thailand. To aid in study of genetic diversity of the species, microsatellite markers, which are specific to C. tribuloides, were developed using whole genome sequencing by next-generation sequencing technology. The primers for microsatellite were developed and screened for optimal annealing temperature by PCR assay. The loci primers specific with C. tribuloides, 13 polymorphic microsatellite primers were successfully developed. The results from genetic information analyzing showed the number of alleles presented were between 2 and 24. Accordingly, the expected and observed heterozygosity obtained were between 0.298 and 0.920 and 0.364 to 1.000, respectively. Null allele frequency was presented 0.000-0.199. Genetic information was generated 10 loci primers significantly deviated from Hardy-Weinberg Equilibrium. All 13 primer pairs of loci were not significant with linkage disequilibrium. A set of microsatellite markers in this study could be applied to gene flow, genetic structure and population genetic studies in the future.

Seasonality of Leaf and Fig Production in Ficus squamosa, a Fig Tree with Seeds Dispersed by Water.

The phenology of plants reflects selection generated by seasonal climatic factors and interactions with other plants and animals, within constraints imposed by their phylogenetic history. Fig trees (Ficus) need to produce figs year-round to support their short-lived fig wasp pollinators, but this requirement is partially de-coupled in dioecious species, where female trees only develop seeds, not pollinator offspring. This allows female trees to concentrate seed production at more favorable times of the year. Ficus squamosa is a riparian species whose dispersal is mainly by water, rather than animals. Seeds can float and travel in long distances. We recorded the leaf and reproductive phenology of 174 individuals for three years in Chiang Mai, Northern Thailand. New leaves were produced throughout the year. Fig production occurred year-round, but with large seasonal variations that correlated with temperature and rainfall. Female and male trees initiated maximal fig crops at different times, with production in female trees confined mainly to the rainy season and male figs concentrating fig production in the preceding months, but also often bearing figs continually. Ficus squamosa concentrates seed production by female plants at times when water levels are high, favouring dispersal by water, and asynchronous flowering within male trees allow fig wasps to cycle there, providing them with potential benefits by maintaining pollinators for times when female figs become available to pollinate.

Riparian Ficus tree communities: the distribution and abundance of riparian fig trees in northern Thailand.

Fig trees (Ficus) are often ecologically significant keystone species because they sustain populations of the many seed-dispersing animals that feed on their fruits. They are prominent components of riparian zones where they may also contribute to bank stability as well as supporting associated animals. The diversity and distributions of riparian fig trees in deciduous and evergreen forests in Chiang Mai Province, Northern Thailand were investigated in 2010-2012. To record the diversity and abundance of riparian fig trees, we (1) calculated stem density, species richness, and diversity indices in 20×50 m randomly selected quadrats along four streams and (2) measured the distances of individual trees from four streams to determine if species exhibit distinct distribution patterns within riparian zones. A total of 1169 individuals (from c. 4 ha) were recorded in the quadrats, representing 33 Ficus species (13 monoecious and 20 dioecious) from six sub-genera and about 70% of all the species recorded from northern Thailand. All 33 species had at least some stems in close proximity to the streams, but they varied in their typical proximity, with F. squamosa Roxb. and F. ischnopoda Miq the most strictly stream-side species. The riparian forests in Northern Thailand support a rich diversity and high density of Ficus species and our results emphasise the importance of fig tree within the broader priorities of riparian area conservation. Plans to maintain or restore properly functioning riparian forests need to take into account their significance.

Ethnobotanical study of medicinal plants used by Tai Yai in Northern Thailand.

ETHNOPHARMACOLOGICAL RELEVANCE: We studied traditional knowledge of medicinal plants used by Tai Yai people in Northern Thailand. We documented traditional medical practices and determined importance among the Tai Yai. This paper reports on knowledge in usage of medicinal plants of the Tai Yai people in Northern Thailand. MATERIALS AND METHODS: Interviews were conducted in 4 Tai Yai villages in Mae Hong Son and Chiang Mai provinces whose inhabitants immigrated from Myanmar at different times. Discussions and interviews were held with 126 key-informants (56 males and 70 females) ranging in age from 16 to 80 years in three age groups (age 16-40, 41-60, and 61-80). We calculated the informant consensus factor (ICF) for use category, use value index (UV) for use report of plant. We tested differences between the knowledge of different age groups and locations using principal component analysis (PCA). RESULTS: These Tai Yai people used of 141 medicinal plants belonging to 59 families. Of the medicinal plant species, the highest percentage was in the family Euphorbiaceae: Croton acutifolius and Croton roxburghii. The highest number of Informant consensus factor was for metabolic system disorders. Overall, Tai Yai people use medicinal plants to cure many sicknesses such as hypertension, lumbago, wounds, puerperium, kidney disorders, kidney stones, coughs, fevers, hemorrhoids, flatulence and malaria. There were no significant differences in knowledge of plants usage among villages of different ages. In addition, the knowledge of the plants was not significantly different between men and women. However, we found that the younger had less experience with and knowledge of medicinal plants than older people. CONCLUSIONS: The result indicates loss of accumulated knowledge of medicinal plants and traditional use. Although, the medicinal plant knowledge was passed from one generation to the next by word of mouth, the detailed documentation of medicinal plants and their use may effectively prevent the knowledge-loss through time.

Karen and Lawa medicinal plant use: uniformity or ethnic divergence?

ETHNOPHARMACOLOGICAL RELEVANCE: We here tease apart the ethnopharmacological knowledge of plants in two Thai villages to determine to which degree the uses are particular to individual ethnic groups and to which degree they are part of a generalized and uniform set of widespread medicinal plants used over a large geographic range. We compared Karen and Lawa knowledge of medicinal plants in the Mae Cheam watershed of northern Thailand, where both ethnic groups have settled and share ecological conditions for resource extraction. We were interested in documenting the degree to which these two ethnic groups use the same or different medicinal plant species. The use of the same plant species by the two groups was considered a sign of uniform and cross-cultural local knowledge, whereas the use of different medicinal plants by each group was considered a sign of culturally specific local knowledge that developed within each ethnic group. MATERIALS AND METHODS: We inventoried the plant species in different habitats around one Karen village and one Lawa village using stratified vegetation plots and using semi-structured questionnaires we interviewed 67 key informants regarding their use of plants for medicine. We then calculated the Fidelity level FL (FL values near 100% for a species indicate that almost all use reports refer to the same way of using the species, whereas low FL values indicate that a species is used for many different purposes) and cultural importance index CI (the sum of the proportion of informants that mention each of the use categories for a given species) to estimate the variation in medicinal plant use. We used Jaccard's Index JI (This index relates the number of shared species to the total number of species) to analyze the similarity of medicinal plant use between the two villages. RESULTS: A total of 103 species of medicinal plant species in 87 genera and 41 families were identified and they were used to cure 35 ailments. The FL of the medicinal plant species varied from 10% to 100%, was different for each ailment, and differed between the two ethnic groups. The most important medicinal plant species, those with the highest CI value, were not the same in the two villages. Costus speciosus, which is used to treat urinary infections and wounds in animals, had the highest CI value in the Karen village, whereas Sambucus javanica, which is used to treat wounds, fractures, bloat, and edema in humans, had the highest CI value in the Lawa village. Only 17 medicinal species (16.5%) were shared between the two villages. Methods of preparation and application were significantly different between the two villages, whereas the plant parts used, habit, and route of administration were similar. CONCLUSION: Our study demonstrates that ethnic groups that live in the same geographic area can have significantly different traditional knowledge systems for medicinal plants, at least when it comes to the species used and their preparation and medicinal application. We assume that differences in cultural history and background in the two villages led to differences in medicinal plant use, preparation, and application.

Medicinal plants from swidden fallows and sacred forest of the Karen and the Lawa in Thailand.

BACKGROUND: Many ecosystem services provided by forests are important for the livelihoods of indigenous people. Sacred forests are used for traditional practices by the ethnic minorities in northern Thailand and they protect these forests that are important for their culture and daily life. Swidden fallow fields are a dominant feature of the agricultural farming landscapes in the region. In this study we evaluate and compare the importance of swidden fallow fields and sacred forests as providers of medicinal plants among the Karen and Lawa ethnic minorities in northern Thailand. METHODS: We made plant inventories in swidden fallow fields of three different ages (1-2, 3-4, 5-6 years old) and in sacred forests around two villages using a replicated stratified design of vegetation plots. Subsequently we interviewed the villagers, using semi-structured questionnaires, to assess the medicinal use of the species encountered in the vegetation survey. RESULTS: We registered a total of 365 species in 244 genera and 82 families. Of these 72(19%) species in 60(24%) genera and 32(39%) families had medicinal uses. Although the sacred forest overall housed more species than the swidden fallow fields, about equal numbers of medicinal plants were derived from the forest and the fallows. This in turn means that a higher proportion (48% and 34%) of the species in the relatively species poor fallows were used for medicinal purposes than the proportion of medicinal plants from the sacred forest which accounted for 17-22%. Of the 32 medicinal plant families Euphorbiaceae and Lauraceae had most used species in the Karen and Lawa villages respectively. CONCLUSION: Sacred forest are important for providing medicinal plant species to the Karen and Lawa communities in northern Thailand, but the swidden fallows around the villages are equally important in terms of absolute numbers of medicinal plant species, and more important if counted as proportion of the total number of species in a habitat. This points to the importance of secondary vegetation as provider of medicinal plants around rural villages as seen elsewhere in the tropics.

Medicinal plants used in Hmong women's healthcare in northern Thailand.

ETHNOPHARMACOLOGICAL RELEVANCE: We studied traditional knowledge of medicinal plants used for women's healthcare in three Hmong villages in northern Thailand and determined how prevalent such knowledge is. We documented traditional medical practices and determined which of the species used are culturally important among the Hmong. MATERIALS AND METHODS: We interviewed six key informants and 147 non-specialist informants about their traditional knowledge of medicinal plants used in Hmong women's healthcare. We selected nine species that were known in all three villages as the domain for questionnaire interviews with 181 additional and randomly selected non-specialist informants. We calculated the Cultural Importance index (CI) for each species and use category. We tested normality of the data, age correlations, and gender correlations with Kolmogorov-Smirnov tests, Spearman's rank correlation coefficient, Kruskal-Wallis test, and Mann-Whitney tests. RESULTS: We documented traditional knowledge of 79 medicinal plants used in women's healthcare. Of these, three species were culturally important to the Hmong. Our questionnaire interviews revealed significant difference in traditional medicinal plant knowledge between genders and age groups. CONCLUSIONS: The Hmong people in northern Thailand possess large amounts of traditional knowledge related to women's healthcare and plants used for this purpose. However, this knowledge, even for the culturally important species, is not possessed by all Hmong and there were signs of knowledge erosion. Preservation of the Hmong intellectual heritage related to medicinal plants used in women's healthcare requires intensive traditional knowledge dissemination to the young Hmong generation.

Growth, morphology, ammonium uptake and nutrient allocation of Myriophyllum brasiliense Cambess. under high NH4⁺ concentrations.

The effects of high NH(4)(+) concentration on growth, morphology, NH(4) (+) uptake and nutrient allocation of Myriophyllum brasiliense were investigated in hydroponic culture. The plants were grown under greenhouse conditions for 4 weeks using four levels of NH(4)(+) concentration: 1, 5, 10 and 15 mM. M. brasiliense grew well with a relative growth rate of c.0.03 day(-1) at NH(4)(+) concentration up to 5 mM. At the higher NH(4)(+) concentrations the growth of the plants was stunted and the plants had short roots and few new buds, especially when grown in 15 mM NH(4)(+) where the submerged leaves were lost and there were rotten roots and submerged stems. To avoid NH(4)(+) toxicity, the plants may have a mechanism to prevent cytoplasmic NH(4)(+) accumulation in plant cells. The net uptake of NH(4)(+) significantly decreased and the total N significantly increased in the plants treated with 10 and 15 mM NH(4)(+), respectively. The plant may employ NH(4)(+) assimilation and extrusion as a mechanism to compensate for the high NH(4)(+) concentrations. However, the plants may show nutrient deficiency symptoms, especially K deficiency symptoms, after they were exposed to NH(4)(+) concentration higher than 10 mM. The present study provides a basic ecophysiology of M. brasiliense that it can grow in NH(4)(+) enriched water up to concentrations as high as 5 mM.

Medicinal plant knowledge and its erosion among the Mien (Yao) in northern Thailand.

ETHNOPHARMACOLOGICAL RELEVANCE: We studied local knowledge and actual uses of medicinal plants among the Mien in northern Thailand, documenting traditional medical practices and its transfer between generations. AIM OF THE STUDY: With the assumption that discrepancies between knowledge and actual use represent knowledge erosion, we studied whether actual use of medicinal plants corresponded to people's knowledge of such uses. MATERIALS AND METHODS: We used local knowledge from four specialist informants as the domain for semi-structured interviews with 34 randomly selected non-specialist informants. We calculated informant consensus, use value, and fidelity level for each species and use category and performed statistical analyses with Kolmogorov-Smirnov tests, Pearson correlation coefficient, Spearman's rank correlation coefficient, and paired-sample t-tests. RESULTS: We found significant discrepancies between knowledge and actual use of medicinal plants. The number of known and actually used plants increased with increasing informant age and decreased with increasing years of formal education. CONCLUSIONS: Medicinal plant knowledge and use in these Mien communities is undergoing inter-generational erosion because of acculturation and interrupted knowledge transmission. Preservation of Mien medicinal plant intellectual heritage requires continued documentation concerning use, conservation, and sustainable management of this resource, which should be publicized to younger Mien.