首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
《农业工程》2022,42(4):274-288
BackgroundManagement of crop pests has been a great challenge around the world. In this study, the plants that are traditionally used as pesticides in southwest Nagaland were identified and documented. Pesticidal plants are an effective alternative to harmful synthetic pesticides and they may help in the formulation of a diverse group of organic pesticides.MethodsInformation on pesticidal plants was obtained through field study and semi-structured interviews. 360 informants from 24 villages were interviewed. Data were analyzed through quantitative tools – use value (UV), informants consensus factor (ICF), fidelity level (FL), and family use value (FUV). Phytochemical analysis of selected plants was done.ResultsIn total, 113 species representing 104 genera and 46 families were documented as pesticidal plants. Asteraceae was the most preferred family as a pesticide with 17 species. Herbs were recorded for 43% of use which was the highest among the habitats. Out of 113 species, 105 species were used as insecticides. Leaf (57.3%; 98 species) was the highest use plant part as a source of pesticides. The highest UV was recorded for Nicotiana tabacum (0.46) with 165 use reports. The ICF value was recorded from 0.96 to 0.97. In regards to FL, several potential pesticidal plants including Azadirachta indica, N. tabacum, Capsicum frutescens, and Curcuma longa were identified with 100% FL each. Phytochemical analysis showed the presence of secondary metabolites like alkaloid, flavonoid, phenol, saponin, tannin, and terpenoid.ConclusionInhabited by a diverse tribal population, the southwest part of Nagaland is a hub of ethnobotanical knowledge. The present study was the first quantitative survey on the plants used as pesticides by the tribal communities of southwest Nagaland and would help modern pharmacology immensely in formulating organic pesticides.  相似文献   

2.
[背景]青海云杉(Picea crassifolia)是中国特有植物,具有极高的生态价值,是西北地区重要的森林更新树种和荒山造林树种,其生长发育及其抗逆性与根系共生真菌多样性密切相关.[目的]从青海云杉根系分离并鉴定定殖的可培养共生真菌,阐明青海云杉根系可培养共生真菌的种类组成,为共生真菌在青海云杉育苗、造林及生态恢复...  相似文献   

3.
《农业工程》2022,42(4):259-268
The utilization of wild medicinal plants in primary healthcare system is still vital for mankind, particularly for people residing nearby the protected area. However, ethnobiological knowledge of indigenous people on plant usage is diminishing. The present study aimed at documenting the wild ethnomedicinal plants and to evaluate their importance in the healthcare among the local inhabitants in the fringe villages of Kitam Bird Sanctuary, South Sikkim, India. The methodology comprised interviews and questionnaire-based household surveys focusing on the informant's knowledge and experience in the use of wild medicinal plants against several diseases and ailments. Data was analysed using relative frequency citation (RFC), use value (UV), informant consensus factor (ICF) and fidelity level (FL%). A total of 23 ethnomedicinal plant species belonging to 20 families were recorded from the study area. Among the growth forms, herbs accounted the highest number of species (39%), followed by trees (30%), climbers (13%), ferns and shrubs with 9% each. Fruits have shown the highest use (20%), followed by leaves (16%) and whole plant. Terminalia chebula had the highest RFC (0.91) and UV (0.99), followed by Terminalia bellirica (RFC = 0.89, UV = 0.96) and Phyllanthus emblica (RFC = 0.84, UV = 0.91). Results indicate that the locals in the area had good ethnobotanical knowledge of medicinal plants which indicates their dependency on plants for treating several ailments and diseases. Some unexplored species such as Calamus erectus, Laportea bulbifera, Pteris biaurita and Solanum viarum possessing high fidelity level have scope for further pharmacological investigation.  相似文献   

4.
《农业工程》2023,43(1):139-153
Amarkantak is a natural heritage site with luxuriant flora on the hilly terrain of Achanakmar-Amarkantak Biosphere Reserve, Central India. The Gonds, Baigas, and other ethnic communities in the area have a wealth of traditional knowledge and practice phytotherapy as health practitioners. The study was undertaken to document the plants of ethnopharmacological significance and their quantitative analyses. The traditional knowledge was collected from informants using open interviews and semi-structured questionnaires. Including 42 health practitioners, a total of 286 respondents were interviewed. The data were analyzed through quantitative indices like Use value (UV), Family use-value (FUV), Relative Importance (RI), Fidelity level (FL), and Informant consensus factor (ICF). The findings on sociocultural demography and therapeutic utilization of plants were discussed in the context of previously published information. The report explained that 173 species belonging to 148 genera and 65 plant families were used against 17 disease categories. The highly mentioned families are Fabaceae (11.5%), Asteraceae (6.9%), Apocynaceae (5.7%), and Lamiaceae (5.7%). The most cited species are Andrographis paniculata, Ocimum sanctum, Tinospora sinensis, Holarrhena pubescens, Cyanoglossum lanceolatum, and Azadirachta indica, within 0.66–0.68 UV. Herbs (45.6%), leaves (17%), and hot infusion (22%) were the most preferred plant forms, employed parts, and recipes for the preparation of drugs. The gastrointestinal illness was the leading cause of concern in the area with 95 reports and a maximum ICF (0.71). The Hypoxidaceae family with a single highly used medicinal plant had the highest FUV (0.54). Curcuma longa (RI: 61.42) was found to be the most suitable species for treating a wide range of body systems. A. paniculata was the most chosen therapeutic plant with the highest FL (90.9). The findings look into a few key plant species with high use values that deserve special attention in drug development. The report recommends that ethnomedicinal plants be studied further for scientific validation after in vitro and in vivo investigations in disease-induced animal models, as well as safety assessments and clinical trials, to ensure safe therapy.  相似文献   

5.
Indigenous knowledge provides information on phytotherapeutic potential of medicinal plants for basic health care mangements in local communinites. The present study was aimed to document folklore knowledge of ethnic communities, who are practicing the herbal medicines in the Jhelum valley (District Hattian), Azad Kashmir, Pakistan. The information regarding folklore use of plants was collected from local communities through informed consent semi- structured interviews from 152 key informants. The ethnobotanical data were quantitatively analyzed using indices of use value (UV), relative frequency citation (RFC) and Informant census factor (ICF). A total of 113 medicinal plant species belong to 52 families were documented in the local communites of Jhelum Valley. The Asteraceae and Polygonaceae were the dominant plant families. The plant species hold potential folklore uses against hepatitis, stomach and respiratory problems, tooth ache, skin ailments and tumor treatment. The whole plants (32.52%), leaves ((21.14%)) were highly consumed plant parts and decoction (22.99%), powder form (18.39%) and infusion (13.79%) was the commonly used method for herbal formulation. The species with maximum use value was Beberis lyceum (0.80) and Valeriana jatamansi (0.60). The highest ICF value was obtained for disease catergories that is ear pain (1.00) followed by heaptic disorder (0.94) and urinary system disorders (0.89). The lowest ICF value was recored for nervous system disorders (0.44). The present study disclosed that traditional knowledge of medicinal plants is still widespread in ethnic people, but gradually decline in youngers. Documentation of newly documented plant species with their folklore uses shall uphold further phytochemical and pharmacological studies.  相似文献   

6.
《农业工程》2021,41(5):365-376
BackgroundThe present study was conducted among the Kani, a tribe settled in the Pechiparai hills of Kanyakumari Wildlife Sanctuary, Western Ghats, to document and quantify their traditional knowledge on the use of medicinal plants for the treatment of various human ailments.MethodsEthnomedicinal data were collected from the Kani by using semi-structured interviews. Data were analyzed by using use value (UV), informant consensus factor (Fic), fidelity level (FL) and family use value (FUV).ResultsIn total, 138 species representing 126 genera belonging to 60 families were reported to have medicinal value and were extensively used by the tribe. Leguminosae was the most speciose family, including 14% (19 species) of identified species. Leaf (50%; 69 species) was found to be the part most used to prepare drugs; leaf extract in the form of juice (26%) was the most widely used preparation; and remedies were often administered orally (53%). The highest UV was recorded for Aristolochia indica (0.35) with 18 use reports, whereas the highest Fic (0.09) was noted for the ailment category ‘fever’. The wide use of Curcuma longa has strong pharmacological evidence – that it is effective in treating various ailments.ConclusionThe present study was the first quantitative survey of the traditional use of medicinal plants by the Kani and will help in the conservation of this invaluable inheritance.  相似文献   

7.
《农业工程》2022,42(1):33-45
The following study is considered as the first ethnobotanical survey in El Kantara's area; the gateway to the Algerian Sahara. The main objective of this survey is to document the indigenous knowledge and to highlight the floristic diversity of this region in order to establish a catalog of traditional medicinal plants used in phytotherapy and the food field, It is useful for subsequent pharmacological research. Ethnobotanical surveys were conducted for two years (2017–2019). The surveys collected sociodemographic data (age, sex, education level) and traditional knowledge on medicinal plants (vernacular name, part used, method of use). The data collected throughout the structured interview was analyzed by using quantitative indices in terms of the value of the use of the species (UV), informant consensus factor (ICF), and fidelity level (FL). A total of 95 informants reported 60 medicinal plants belonging to 29 botanical families of which 11 species have food usage. Asteraceae was the most common family (21.66%), followed by the Lamiaceae family (15%). Results of sociodemographic data showed the predominance of female sex with (64.21%), the majority of surveyed people are aged between 40 and 50 years old, while (67.37%) of the informants were illiterate. Artemisia herba-alba Asso was the most frequently used by the local population, with the highest UV of 1.26 (120 usage reports). The leaves were most used, while infusion was the most preferred form of use. New usage of 28 species was documented. Gastrointestinal system disorders and cardiovascular system diseases had the highest ICF (0.94) with 451 and 261 use reports respectively. The most common species Paronychia argentea Lam. was used for kidney disorders with a degree of fidelity of 100%. This study has highlighted the importance of traditional medicine in the El Kantara area and revealed a wealth of ethnobotanical knowledge in phytotherapy and the food sector. Findings should be subjects of further pharmacological and food studies to isolate bioactive compounds and validate their use.  相似文献   

8.
《农业工程》2022,42(2):19-33
Garam Chashma valley is a mountainous valley situated in the Hindukush mountain range in Pakistan. This area is blessed with rich and diverse medicinal flora extensively utilized by the local community to cure health issues. The present article aims to explore and document the indigenous traditional knowledge about wild plants and their curative properties. This survey was carried out during April 2018 to September 2019. Data was collected from 153 indigenous people through semi structure questionnaire, group discussion, field survey and formal talks with elder people. Quantitative analysis of recorded data was obtained by applying quantitative indices like Frequency of Citation (FC) Use Reports (UR), Family Use Value (FUV), Informant Consensus Factor (ICF), Use Value (UV) and Relative Frequency of Citation (RFC). About 83 plant taxa belonging to 36 different families were recorded for the treatment of 95 different disorders grouped into sixteen disease categories. Herbs were the most leading plant habit (81.9%) and dried plant material (51.8%) usually preferred for therapeutics uses. Among families Asteraceae (16.86%) was recorded as major taxon with highest number of species followed by Lamiaceae (12.06%). Leaves 33% were recorded most abundantly used plant part followed by flowers (17%). Regarding to formulations, decoction (39.3%) and powder (17.1%) were recorded most frequent mode of preparation while oral intake (78%) was most preferred administration route. About (40%) plants species were utilized to treat Gastrointestinal diseases (GIT) disorders. Informant consensus revealed that Gastrointestinal disorders and Dermatological disorders were top ranked ailments categories with 0.94 consensus. The current study imparted that medicinal plants are still used by the indigenous communities of Garam Chashma valley, district lower Chitral, Pakistan. Thus, this investigation provides basis for the conservation of medicinal flora in the area. Medicinal plants (MPs) having high value of FC, RFC, UV, FUV, FL and ICF should be further study for phytochemistry and ethnopharmacology to evaluate novel active ingredients for new drugs discovery.  相似文献   

9.
《Phytomedicine》2014,21(12):1534-1542
PurposeBergenia crassifolia (L.) Fritsch, a species in the Bergenia genus belongs to the family Saxifragaceae, is valuated for its medicinal application. The review focuses on the medicinal uses, phytochemistry, and the biological activities of B. crassifolia to explore its benefits and potential uses.MethodsIn this review, we summarized data, published in Russia and in other countries related to B. crassifolia.ResultsRhizomes and leaves of this plant are in use as traditional remedies for the treatment of different disorders in the folk medicine systems of Russia and Asia. The plant is a potential source of tannins, benzanoids, flavonoids, polysaccharides and other active compounds. Due to the presence of a multitude of bioactives, a wide array of pharmacological activities have been ascribed to different parts of this herb and individual compounds, which include adaptogenic, antiinflammatory, antihypertensive, antimicrobial, antioxidant, antiobesity, antitussive, cerebro-protective, hepatoprotective, immunomodulating, and diuretic.ConclusionThe review highlights the potential of B. crassifolia for further development of herbal medicines on its base.  相似文献   

10.
《农业工程》2023,43(1):34-46
BackgroundTribal people of India still use ancient traditional health care practices, using available plants in their surroundings. Traditional knowledge of medicine is vanishing due to urbanization and outmigration thus its urgent need to preserve this valuable knowledge.MethodsThis recent study was carried out in Pakyong subdivision of East Sikkim during 2016–17, and information was collected interviewing 71 informants of the Lepcha, Bhotia, and Nepali tribes.ResultsPresent study documenting 60 useful plant species belonging to 38 families, used for local health care needs including ten veterinary useful species. Herbaceous plants were used in high proportion (32 species, 54%) followed by trees (20, 33%), shrubs (20, 8%) and climbers (3, 5%). Leaves were the most frequently used plant parts and decoction was the common drug formulation among the inhabitants. The Informant consensus factor (ICF) ranged between 0.88 and 0.97, and fidelity levels in the study region were varied from 11.53% to 100%.ConclusionDocumentation of local plant uses by tribal people will be helpful in sustainable use of indigenous practices of medicinal plants, and further information may be used for pharmacological investigation and novel phytoconstituents isolation.  相似文献   

11.
《农业工程》2019,39(5):380-397
The present study aims to document data about the traditional uses of plants in health-care trainers among the local peoples of areas which may lead to natural drug invention development. There is urgency in recording such data for ethnobotanical studies using many statistical calculations were applied. Totally, 137 informants were selected from 8 villages by their traditional knowledge about medicinal plants. The collected specimens were statistically analyzed by Frequency citation (FC), Relative frequency citation (RFC), Use values (UV), Relative importance (RI), Cultural index (CI), Frequency index (FI) and Pearson correlation Co-efficient. Totally, 85 medicinal plants belonging to 73 families were documented through traditional people of Thanjavur for the treatment of 17 different ailments in which paste based herbal medicine is highly used (30%). Among the families, Acanthaceae, Euphorbiaceae and Malvaceae are dominant species with each five, Solanaceae with four species, Amaranthaceae, Apiaceae, Convulcacaeae, Aizoaceae, Apocynaceae, Lamiaceae and Rubiaceae with each three species and Capparaceae, Lythraceae, Anacardiaceae are recorded each two species and remaining families were one species respectively. In this quantitative ethnobotanical analysis, the high use values were recorded as Solanum trilobatum (1.31), Thespesia populnea (1.30), Cissus quadrangularis (1.26), Trianthema portulacastrum (1.76), and Hygrophila auriculata. Phyllanthus niruri showed high RI values than other plants. Pearson correlation coefficient between RFC and UV was 0.802 with P-value <1%. From this study, we can recommend that statistically proved medicinal plants like Solanum trilobatum, Thespesia populnea, Cissus quadrangularis, Trianthema portulacastrum, Hygrophila auriculata, Phyllanthus niruri and Achyranthes aspera were also needed for further investigation on pharmacologically which leads to natural drug invention development.  相似文献   

12.

Background

Spices have always been used for their flavor-enhancement characteristics and for their medicinal properties. In Benin, scientific research on spices is scarce, despite their importance in the local population’s daily needs. This study investigated the diversity of wild spices and documented the associated traditional knowledge that can be used for their valuation, domestication, and sustainable management in the Sudano-Guinean Zone of Benin.

Methods

Data were collected during field expeditions using semi-structured interviews in ten localities across the three phytodistricts of the zone. Species richness and Shannon’s diversity index were estimated using species accumulation curves. Use report (UR), cultural importance, use value (UV) index, and informant consensus factor (Fic) were used to assess traditional knowledge on wild species, their local importance, and informants’ agreement among sociolinguistic groups. Priority wild spices were finally identified using an approach combining eight criteria (native status, economic value, ethnobotanical value, global distribution, national distribution, in-situ and ex-situ conservation status, legislation, and threats assessment) in four prioritization methods (point scoring procedure, point scoring procedure with weighting, compound ranking system, and binomial ranking system).

Results

A total of 14 species, belonging to 12 genera and 9 families, were inventoried. The most prominent families were Zingiberaceae (21.43%), Annonaceae (21.43%), and Rutaceae (14.29%). More than 200 specific uses were reported, with the Tchabè people holding the greatest level of knowledge (70 uses; UR?=?5.70?±?0.33). The culturally most important spices differed among sociolinguistic groups. Most of the informants agree on the use of the species among (Fic = 0.72–0.98) and across the considered use categories (Fic = 0.88–0.99). The highest UV were registered for Aframomum alboviolaceum (UV?=?0.93), Lippia multiflora (UV?=?0.76), and Aframomum angustifolium (UV?=?0.18). Overall, people perceived wild spices as declining due to agriculture, grazing, and drought. Five species, A. alboviolaceum, L. multiflora, Monodora tenuifolia, Xylopia aethiopica, and Z. zanthoxyloides, were the most prioritized for conservation.

Conclusions

This study provides information relevant for the implementation of conservation and domestication actions of wild spices in Benin. Priority species could be integrated into traditional agroforestry systems (e.g., home gardens). However, for this to be effective, further research should be undertaken on morphological and genetic diversity and propagation methods of priority wild spices.
  相似文献   

13.

Background

This explorative study was undertaken for the first time in Kel village located in the Upper Neelum Valley, Azad Kashmir, Pakistan. The purpose was to document the indigenous knowledge of the native people used in the preparation of herbal medicines.

Methods

To get the data on traditional uses of medicinal plants, 20 informants were interviewed. Quantitative ethnobotanical indices, i.e., use value (UV), relative frequencies of citation (RFC), informant consensus factor (Fic), fidelity level (FL), data matrix ranking (DMR), preference ranking (PR), and jaccard index (JI), were calculated for the recorded medicinal plants.

Results

A total of 50 medicinal plants belonging to 33 families used in 13 disease categories were documented. Leaves were the frequently used plant parts, and decoction was the commonly used method for herbal medicine. Plants with high use value were Berberis lycium (2.05), Impatiens glandulifera (1.95), Artemisia scoparia (1.75), Ageratum conozoides (1.75), and Achillea millefolium (1.7). The highest RFC value was calculated for Berberis lycium (0.75), Cynoglossum lanceolatum (0.65), and Impatiens glandulifera and Achillea millefolium (0.60 each). The maximum informant consensus factor was for urinary system, cardiac diseases, baldness, and abortion and miscarriage (1.00). Berberis lyceum (95%) used in jaundice, hepatitis, typhoid, fever, and tuberculosis disorders. Plants with maximum fidelity level (FL) were Berberis lycium (95%) followed by Dioscorea bulbifera, Impatiens glandulifera, and Artemisia vulgaris (90%). Olea ferruginea was the most multipurpose plant and exports (21.2%) was the leading threat in the area. The pearson correlation coefficient (0.500) showed a positive correlation between the use value and relative frequency of citation.

Conclusion

The present study provides useful information about traditional uses of medicinal plants used by local communities in different ailments. The plants with the highest use values could be employed in pharmacological research and biotechnological approaches in order to achieve adequate revenue. Some of the plants in the study area are facing high threats of becoming rare, and conservation initiatives are needed to conserve them for sustainable management in the region.
  相似文献   

14.
An ethnobotanical study was conducted from October 2005 to June 2006 to investigate the uses of medicinal plants by people in Zegie Peninsula, northwestern Ethiopia. Information was gathered from 200 people: 70 female and 130 males, using semistructured questionnaire. Of which, six were male local healers. The informants, except the healers, were selected randomly and no appointment was made prior to the visits. Informant consensus factor (ICF) for category of aliments and the fidelity level (FL) of the medicinal plants were determined. Sixty-seven medicinal plants used as a cure for 52 aliments were documented. They are distributed across 42 families and 64 genera. The most frequently utilized plant part was the underground part (root/rhizome/bulb) (42%). The largest number of remedies was used to treat gastrointestinal disorder and parasites infections (22.8%) followed by external injuries and parasites infections (22.1%). The administration routes are oral (51.4%), external (38.6%), nasal (7.9%), and ear (2.1%). The medicinal plants that were presumed to be effective in treating a certain category of disease, such as 'mich' and febrile diseases (0.80) had higher ICF values. This probably indicates a high incidence of these types of diseases in the region, possibly due to the poor socio-economic and sanitary conditions of this people. The medicinal plants that are widely used by the local people or used as a remedy for a specific aliment have higher FL values (Carissa spinarum, Clausena anisata, Acokanthera schimperi, Calpurnia aurea, Ficus thonningii, and Cyphostemma junceum) than those that are less popular or used to treat more than one type of aliments (Plumbago zeylanicum, Dorstenia barnimiana).  相似文献   

15.
In this work, ten species morphologically similar to Q. crassifolia are circumscribed based on a phylogenetic species concept. Examination of these species suggests that Q. dysophylla and Q. radiata are of hybrid origin; the putative parents of Q. dysophylla are Q. crassifolia and Q. crassipes, while Q. radiata is likely the result of hybridization between Q. coccolobifolia and Q. conzattii or Q. urbanii. A lectotype of Q. crassifolia is designated here. Dichotomous keys, as well as distribution ranges and photographs, are presented.  相似文献   

16.
Cryptosporidium spp., ubiquitous enteric parasitic protozoa of vertebrates, recently emerged as an important cause of economic loss and zoonosis. The present study aimed to determine the distribution and species of Cryptosporidium in post-weaned and adult pigs in Shaanxi province, northwestern China. A total of 1,337 fresh fecal samples of post-weaned and adult pigs were collected by sterile disposable gloves from 8 areas of Shaanxi province. The samples were examined by Sheather’s sugar flotation technique and microscopy at×400 magnification for Cryptosporidium infection, and the species in positive samples was further identified by PCR amplification of the small subunit (SSU) rRNA gene. A total of 44 fecal samples were successfully amplified by the nested PCR of the partial SSU rRNA, with overall prevalence of 3.3%. The average prevalence of Cryptosporidium infection in each pig farms ranged from 0 to 14.4%. Species identification by sequencing of SSU rRNA gene revealed that 42 (3.1%) samples were Cryptosporidium suis and 2 (0.15%) were Cryptosporidium scrofarum. C. suis had the highest prevalence (7.5%) in growers and the lowest in breeding pigs (0.97%). C. suis was the predominant species in pre-weaned and adult pigs, while C. scrofarum infected pigs older than 3 months only. A season-related difference of C. suis was observed in this study, with the highest prevalence in autumn (5.5%) and the lowest (1.7%) in winter. The present study provided basic information for control of Cryptosporidium infection in pigs and assessment of zoonotic transmission of pigs in Shaanxi province, China.  相似文献   

17.
Leaves of 22 accessions of the Bulgarian raspberry (Rubus L.) germplasm collection – five Bulgarian and seven foreign cultivars, eight elite clones and two wild species, Rubus occidentalis L. and Rubus odoratus L., were analysed for phenolic constituents. The quantitative determination of caffeic (1), p-coumaric (2) and ferulic (3) acids, hyperoside (4), tiliroside (5), and isoquercitrin (6) was performed by RP-HPLC using linear gradient elution and UV detection at 254 and 310 nm. The detection limits ranged from 0.23 μg/ml (4) to 0.55 μg/ml (2). Caffeic acid was the dominant phenolic acid in the majority of the samples being present in amounts between 0.05 ± 0.01 mg/g dry weight in R. occidentalis and 1.43 ± 0.06 mg/g in the cultivars. The highest content of flavonols was found in the Bulgarian raspberry elite clones: 1.70 ± 0.002 mg/g (6), 0.60 ± 0.004 mg/g (5) and 0.97 ± 0.01 mg/g (4). Data were analyzed by hierarchical clustering (HC) and principal component analysis (PCA). The HC and PCA scoring plot showed that the samples could be classified into three clusters. Cluster C1 comprised cultivars characterized by high content of phenolic acids (1–3). Seven cultivars and the wild species R. occidentalis formed the cluster C2 presenting low content of phenolic compounds. Cluster C3 grouped the Bulgarian raspberry elite clones and R. odoratus sharing the highest content of flavonols (5 and 6). The Bulgarian elite clone E23617 displayed the highest content of the studied phenolic derivatives. The PCA loading plot showed that 1 can be used to distinguish between different raspberry varieties.  相似文献   

18.
19.
Precipitation is one of the most important climate factors controlling tree growth, yet it is not fully understood how changes in precipitation affect the relationship between growth and temperature. On the northeastern edge of the Tibetan Plateau, nine tree-ring chronologies of Picea crassifolia were developed along a precipitation gradient from semi-arid (mean annual precipitation, 255 mm) to semi-humid (710 mm). We analyze the growth-climate relationships along this precipitation gradient and assess whether these associations are regulated by local precipitation. From 1960 to 2014, temperature increased significantly while precipitation remained stable at the nine sampling sites. The radial growth of P. crassifolia decreased at the semi-arid sites but increased at the semi-humid sites. Growth-temperature relationships gradually changed from negative to positive along the precipitation gradient (from dry to wet sites), particularly during summer. The moist P. crassifolia sites are also characterized by positive correlations with the Palmer Drought Severity Index. The temporal growth-temperature relationships varied significantly among the different spruce sites over the last five decades. Although temperature remains the main factor controlling the growth of P. crassifolia, local precipitation variability is becoming increasingly important. Our findings indicate that considering species distribution areas supports the analyses of the impact of climate change on tree growth.  相似文献   

20.
We describe four new species of Ruellia from Costa Rica; three from the Osa Peninsula, Puntarenas province (R. exilis, R. mira, R. odorata), and one from the southwestern corner of San José province (R. norvegigratiosa). Ruellia matagalpae is reported as a new record for the country. New combinations are made in Ruellia for the two Costa Rican species of Blechum (R. blechum and R. costaricensis). Three species are reduced to synonymy, and another species is considered doubtfully worthy of recognition. Notable range extensions are reported for two species. Corollas and fruits of all 22 Costa Rican species of Ruellia are shown and compared as easily used identification aids. An informal guide to species groups and a dichotomous key to the 22 species are presented.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号