The present study aimed to predict differential enrichment of pathways and compounds in the rhizosphere microbiomes of the two wild plants(Abutilon fruticosum and Nitrosalsola vermiculata)and to predict functional shi...The present study aimed to predict differential enrichment of pathways and compounds in the rhizosphere microbiomes of the two wild plants(Abutilon fruticosum and Nitrosalsola vermiculata)and to predict functional shifts in microbiomes due to water.Amplicon sequencing of 16S rRNA region V3–V4 was done and gene-based microbial compositions were enrolled in PICRUSt to predict enriched pathways and compounds.The results indicated that“ABC transporters”and“Quorum sensing”pathways are among the highest enriched pathways in rhizosphere microbiomes of the two wild plants compared with those of the bulk soil microbiomes.The highest enriched compounds in soil microbiomes of the two wild plants included five proteins and three enzymes participating in one or more KEGG pathways.Six of these eight compounds showed higher predicted enrichment in rhizosphere soil microbiomes,while only one,namely phosphate transport system substrate-binding protein,showed higher enrichment in the surrounding bulk soil microbiomes.In terms of differentially enriched compounds due to watering,only the dual-specific aspartyl-tRNA(Asn)/glutamyl-tRNA(Gln)amidotransferase subunit A showed higher enrichment in rhizosphere soil of the two wild plants after 24 h of watering.Two of the highly enriched compounds namely branched-chain amino acid transport system ATP-binding protein and branched-chain amino acid transport system substrate-binding protein,are encoded by genes stimulated by the plant’s GABA that participates in conferring biotic and abiotic stresses in plants and improves the plant’s growth performance.The 3-Oxoacyl-[ACP]reductase,a member of the short-chain alcohol dehydrogenase/reductase(SDR)superfamily,participates in fatty acids elongation cycles and contributes to plant-microbe symbiotic relationships,while enoyl-CoA hydratase has a reverse action as it participates in“Fatty acid degradation”pathway.The methyl-accepting chemotaxis protein is an environmental signal that sense“Bacterial chemotaxis”pathway to help establishing symbiosis with plant roots by recruiting/colonizing of microbial partners(symbionts)to plant rhizosphere.This information justifies the high enrichment of compounds in plant rhizosphere.The dual-specific aspartyl-tRNA(Asn)/glutamyl-tRNA(Gln)amidotransferase subunit A contributes to the plant ability to respond to watering as it participates in attaching the correct amino acid during translation to its cognate tRNA species,while hydrolyzing incorrectly attached amino acid.These two actions reduce the influence of oxidative stress in generating misfolded proteins and in reducing fidelity of translation.展开更多
A study was conducted on the newly promulgated key protected wild plants distributed in the Dabie Mountains National Nature Reserve in Hubei in 2021.According to statistics,Dabie Mountains National Nature Reserve of H...A study was conducted on the newly promulgated key protected wild plants distributed in the Dabie Mountains National Nature Reserve in Hubei in 2021.According to statistics,Dabie Mountains National Nature Reserve of Hubei Province has a total of 41 species of wild plants under national key protection,including 7 species in the first class and 34 species in the second class.Among them,6 are cultivated species,4 in the first class,and 2 species in the second class.The characteristics of Chinese key protected wild plants in the Dabie Mountains National Nature Reserve in Hubei Province were analyzed.展开更多
[Objective] The aim was to study the current situation and protection countermeasures of wild plant resources in Xishuangbanna National Nature Reserve. [Method] The current situation of wild plant resources in Xishuan...[Objective] The aim was to study the current situation and protection countermeasures of wild plant resources in Xishuangbanna National Nature Reserve. [Method] The current situation of wild plant resources in Xishuangbanna National Nature Reserve was researched by means of route survey, sample plot survey and literature survey, and then the main impact factors of wild plant resources were analyzed by using participatory rural appraisal and problem tree analysis, finally protection countermeasures were put forward according to current situation and main impact factors. [Result] There were 2 779 species of vascular plants belonging to 214 families and 1 012 genera (including subfamilies and varieties) in Xishuangbanna National Nature Reserve, among them, there existed 261 species of pteridophyte belonging to 41 families and 91 genera, 14 species of gymnosperm belonging to 6 families and 6 genera, and 2 504 species of angiosperm belonging to 167 families and 915 genera. Wild plant resources in reserve were mainly affected by planting under forest, habitat fragmentation, cutting trees, collection and utilization of no-timber products, development of animal husbandry, insufficient recognition of community residents to reserve management establishment and lots of floating population. In the future, wild plant resources in reserve could be protected through strengthening propaganda, education and management, enforcing the law strictly and other countermeasures. [Conclusion] The study could provide theoretical foundation for the protection of wild plant resources in Xishuangbanna National Nature Reserve.展开更多
This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic res...This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic resources and the sustainable development of flowers and plants industry in China, and put forward some proposals on the existing question and the prospects for the development.展开更多
Plants in natural ecosystems are exposed to a combination of UV radiation,ionizing radiation(IR)and other abiotic factors.These factors change with the altitude.We investigated DNA alterations of some wild plants of d...Plants in natural ecosystems are exposed to a combination of UV radiation,ionizing radiation(IR)and other abiotic factors.These factors change with the altitude.We investigated DNA alterations of some wild plants of different plant families in natural ecosystems at three altitudes in Rila Mountain,Bulgaria(1500,1782,and 2925 m above sea level(a.s.l.)exposed to UV radiation,IR and other abiotic stresses,to assess the tolerance of plant species to the changing environmental conditions in three successive growth seasons.For this purpose,physicochemical,cytogenetic,and molecular methods were applied.DNA damage was assessed by micronucleus test and molecular method comet assay adapted and applied by us to wild plant species from Onagraceae,Rosaceae,Boraginaceae,Saxifragaceae,Orobanchaceae,Asteraceae and Poaceae families,growing at three different altitudes.Variability in the DNA sensitivity and the level of tolerance was observed among the plant species in response to combined abiotic factors assessed by induced DNA damage and gross beta activity.The studied representatives of Poaceae were less susceptible than the other studied species at all three altitudes and showed close level of DNA injuries to that of unaffected control plant grown in laboratory conditions.The lower levels of DNA damage of these wild plant species corresponded to their lower ability to accumulate radionuclides.There was a particularly pronounced low level of DNA injuries in the plant species at the highest altitude.The level of DNA damage showed correlation with the values of some abiotic environmental factors.The results would contribute to the elucidation of the extent of adaptation of plant species to the continuously changing environment and would be useful in selecting sensitive herbaceous monitor species for environmental impact assessment at mountain and alpine sites.展开更多
Objective:To evaluate the nutritional composition and elemental constituents of Kedrostis africana and their safety aspect.Methods:Proximate parameters(moisture,ash,crude fibre,crude fat,proteins,and carbohydrate and ...Objective:To evaluate the nutritional composition and elemental constituents of Kedrostis africana and their safety aspect.Methods:Proximate parameters(moisture,ash,crude fibre,crude fat,proteins,and carbohydrate and energy) were evaluated using ALASA methods,and elemental analysis by ICP-OES technique.Results:The results from nutritional analysis showed that the tuber used for this study had a low content of crude fat and high content of ash,crude protein,crude fibre,carbohydrate and energy having the recommended dietary allowances.The tuber was rich in major minerals Na,K,Ca and Mg,there was sufficient amount of trace elements Fe,Cu,and Zn while the anti-nutrients oxalate,phytate,alkaloids,and saponins were detected in amounts that are not harmful according to Food and Agriculture Organization/World Health Organization.Conclusions:The outcome of this study suggests that this wild plant has very good nutritional potentials to meet the recommended dietary allowance and it could be a cheap source of essential nutrients that may ameliorate most nutritional challenges and can contribute remarkably to the amount of nutrient intake in human and animal diet.展开更多
In recent years,the protection of PSESP has gradually become a hot issue in biodiversity research.Through the investigation and analysis of PSESP in Xinjiang,it is shown that:①there are 75 species of PSESP in Xinjian...In recent years,the protection of PSESP has gradually become a hot issue in biodiversity research.Through the investigation and analysis of PSESP in Xinjiang,it is shown that:①there are 75 species of PSESP in Xinjiang,including 22 species of trees,18 species of shrubs and 35 species of herbs.The habitats are mainly in extremely cold,extremely dry or extremely narrow conditions such as snow line,desert,mountain,wetland and so on.②53 species(70.67%)are listed as national or autonomous region protected plants,and 22 species of PSESP are not listed in the protection;there are 70 species of PSESP listed in the red list,accounting for 93.33%.③The PSESP in Xinjiang are mainly distributed in the Altai Mountains,western Tianshan Mountains,Pamir Plateau and Karakoram Mountains;they are distributed in all kinds of nature reserves,forest parks,wetland parks and other natural ecological protection areas in Xinjiang.Ammopiptanthus nanus(M.Pop.)Cheng F.,Cistanche tubulosa(Schenk)Wight,Calligonum roborovskii A.Los.and Prunus cerasifera Ehrhart have not been found in the literature,indicating that they are distributed in protected areas.In order to provide a theoretical basis for the conservation of biodiversity in Xinjiang,this paper puts forward some suggestions on the protection of PSESP.展开更多
We review achievements in the conservation of orchid diversity in China over the last 21 years.We provide updated information on orchid biodiversity and suggestions for orchid conservation in China.We outline national...We review achievements in the conservation of orchid diversity in China over the last 21 years.We provide updated information on orchid biodiversity and suggestions for orchid conservation in China.We outline national policies of biodiversity conservation,especially of orchid conservation,which provide general guidelines for orchid conservation in China.There are now approximately 1708 known species of Orchidaceae in 181 genera in China,including five new genera and 365 new species described over the last 21 years.The assessment of risk of extinction of all 1502 known native orchid species in China in 2013 indicated that 653 species were identified as threatened,132 species were treated as data-deficient,and four species endemic to China were classified as extinct.Approximately 1100 species(ca.65%)are protected in national nature reserves,and another~66 species in provincial nature reserves.About 800 native orchid species have living collections in major botanical gardens.The pollination biology of 74 native orchid species and the genetic diversity and spatial genetic structure of 29 orchid species have been investigated at a local scale and/or across species distributions.The mycorrhizal fungal community composition has been investigated in many genera,such as Bletilla,Coelogyne,Cymbidium,Cypripedium,and Dendrobium.Approximately 292 species will be included in the list of national key protected wild plants this year.Two major tasks for near future include in situ conservation and monitoring population dynamics of endangered species.展开更多
The seasonal fluctuation oflepidoptcran cereal stemborers on maize and wild host plants (i.e., grasses and a few sedges) was investigated in southern Benin from 1988 to 1998 by time series analysis and repeated-meas...The seasonal fluctuation oflepidoptcran cereal stemborers on maize and wild host plants (i.e., grasses and a few sedges) was investigated in southern Benin from 1988 to 1998 by time series analysis and repeated-measures analysis of variance (ANOVA). In addition, a walk-in light trap was used to study the flight behavior of adult moths. On both cereals and grasses, the noctuid Sesamia calaraistis was the predominant species, followed by the pyralid Eldana saccharina. The noctuid Busseolafusca was rare on both maize and wild host plants. In general, pest populations increased during the course of the year to reach peak densities during the second short rainy season, and then crashed to close to zero during the dry season. On wild host plants, egg masses and other immature stages were collected throughout the year but they were higher on wild grasses than maize during the off-season. Thus wild host plants can be considered as refuge for both borers and natural enemies during the off-season, when maize is not available. However, only four out of the eleven wild host species played a discernable role. S. calamistis egg densities appeared to be influenced by density-dependent factors, suggesting an effect of natural enemies. Temperature and rainfall had a negative effect on egg abundance. Larval parasitism by a Kenyan strain of the braconid Cotesia sesamiae, which was released in southern Benin in the early 1990s, and by the tachinid Sturmiopsisparasitica varied between seasons and years but there were no discernable patterns. For both parasitoids and borer host species, parasitism was positively correlated with trap catches of adult moths. The recovery of C. sesamiae during a 2-year period suggests that the parasitoid has established its population in southern Benin.展开更多
The aim of this study was to determine the allelopathic effects of <i><span style="font-family:Verdana;">Azadirachta indica</span></i><span style="font-family:Verdana;"&g...The aim of this study was to determine the allelopathic effects of <i><span style="font-family:Verdana;">Azadirachta indica</span></i><span style="font-family:Verdana;"> oil and aqueous extracts of </span><i><span style="font-family:Verdana;">Tithonia diversifolia</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Thevetia peruviana</span></i><span style="font-family:Verdana;"> on the growth and stimulation of metabolites involved in tomato plant resistance. Randomized in blocks within a shaded area, the different treatments prepared at 10% and 15% (v/v and w/v) in water were subsequently applied on tomatoes seeds to monitor the effect on germination, and on tomatoes leaves to monitor the effect on growth and resilience of the plants. The result showed that in stressful conditions all the treatment</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> significantly inhibit (p < 0.05) the germination capacity of the seeds from 21.22% to 92.61%, the germination rate from 39.82% to 92.76% and the germination viability of the seedlings from 64.67% to 100%. However, the negative allelopathic effect of the treatment was significantly reduced (p < 0.05) when used for germination initiation by botanical priming. In addition, while </span><i><span style="font-family:Verdana;">T. diversifolia</span></i><span style="font-family:Verdana;"> at 10% promotes a better aerial and root growth in tomato plants, </span><i><span style="font-family:Verdana;">T. peruviana</span></i><span style="font-family:Verdana;"> at 15% induces the activation of resistance mechanisms in tomato plants by increasing protein levels to 104.5%, phenol levels to 183.33% and peroxidase enzyme activity to 586.15%. Therefore, allelopathic compound of wild plants would be a good alternative for growth promotion and resistance of tomato crops.</span></span></span></span>展开更多
Geminiviruses, in particular the members of the genus Begomovirus , are considered to be a major phytosanitary problem for tomato crops production in the world. They are responsible for yield losses of up to 20% to 10...Geminiviruses, in particular the members of the genus Begomovirus , are considered to be a major phytosanitary problem for tomato crops production in the world. They are responsible for yield losses of up to 20% to 100%. Regrettably, Togo is not spared from this situation. This work aims to show the genetic diversity of the begomoviruses affecting tomato crops production in Togo and their relationship with other begomoviruses. To achieve these objectives, 307 samples of tomato leaves and wild plant species with typical virus symptoms were collected in the Maritime, Plateaus, Central, Kara and Savannah regions and submitted to PCR analysis. The results revealed the presence of begomovirus in 25.40% of the analyzed samples. The PCR products obtained were submitted to direct sequencing. Phylogenetic analysis of sequences of DNA-A different regions of begomovirus identified in this work with that of other begomoviruses showed a nucleotide identity of 96% respectively for Tomato leaf curl Togo virus-Fontem, Tomato Leaf Curl Togo Virus , Ageratum leaf curl Cameroon Alphasatellite;98% respectively to Tomato leaf curl Nigeria virus , Ageratum leaf curl Cameroon virus , Tomato leaf curl Cameroon virus-Fontem, Ageratum leaf curl Cameroon virus and 99% respectively to Tomato leaf curl Kumasi virus , Pepper yellow vein Mali virus Bazegahot and Pepper yellow vein Mali virus-Ouaga. These results suggest a high degree of genetic diversity of tomato begomoviruses identified in Togo.展开更多
文摘The present study aimed to predict differential enrichment of pathways and compounds in the rhizosphere microbiomes of the two wild plants(Abutilon fruticosum and Nitrosalsola vermiculata)and to predict functional shifts in microbiomes due to water.Amplicon sequencing of 16S rRNA region V3–V4 was done and gene-based microbial compositions were enrolled in PICRUSt to predict enriched pathways and compounds.The results indicated that“ABC transporters”and“Quorum sensing”pathways are among the highest enriched pathways in rhizosphere microbiomes of the two wild plants compared with those of the bulk soil microbiomes.The highest enriched compounds in soil microbiomes of the two wild plants included five proteins and three enzymes participating in one or more KEGG pathways.Six of these eight compounds showed higher predicted enrichment in rhizosphere soil microbiomes,while only one,namely phosphate transport system substrate-binding protein,showed higher enrichment in the surrounding bulk soil microbiomes.In terms of differentially enriched compounds due to watering,only the dual-specific aspartyl-tRNA(Asn)/glutamyl-tRNA(Gln)amidotransferase subunit A showed higher enrichment in rhizosphere soil of the two wild plants after 24 h of watering.Two of the highly enriched compounds namely branched-chain amino acid transport system ATP-binding protein and branched-chain amino acid transport system substrate-binding protein,are encoded by genes stimulated by the plant’s GABA that participates in conferring biotic and abiotic stresses in plants and improves the plant’s growth performance.The 3-Oxoacyl-[ACP]reductase,a member of the short-chain alcohol dehydrogenase/reductase(SDR)superfamily,participates in fatty acids elongation cycles and contributes to plant-microbe symbiotic relationships,while enoyl-CoA hydratase has a reverse action as it participates in“Fatty acid degradation”pathway.The methyl-accepting chemotaxis protein is an environmental signal that sense“Bacterial chemotaxis”pathway to help establishing symbiosis with plant roots by recruiting/colonizing of microbial partners(symbionts)to plant rhizosphere.This information justifies the high enrichment of compounds in plant rhizosphere.The dual-specific aspartyl-tRNA(Asn)/glutamyl-tRNA(Gln)amidotransferase subunit A contributes to the plant ability to respond to watering as it participates in attaching the correct amino acid during translation to its cognate tRNA species,while hydrolyzing incorrectly attached amino acid.These two actions reduce the influence of oxidative stress in generating misfolded proteins and in reducing fidelity of translation.
基金Supported by 2022 Capacity Building Project of Hubei Dabie Mountains National Nature Reserve(20120220002)Joint Open Fund for Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization and Hubei Collaborative Innovation Center for the Characteristic Resources Exploitation of Dabie Mountains(202020604).
文摘A study was conducted on the newly promulgated key protected wild plants distributed in the Dabie Mountains National Nature Reserve in Hubei in 2021.According to statistics,Dabie Mountains National Nature Reserve of Hubei Province has a total of 41 species of wild plants under national key protection,including 7 species in the first class and 34 species in the second class.Among them,6 are cultivated species,4 in the first class,and 2 species in the second class.The characteristics of Chinese key protected wild plants in the Dabie Mountains National Nature Reserve in Hubei Province were analyzed.
文摘[Objective] The aim was to study the current situation and protection countermeasures of wild plant resources in Xishuangbanna National Nature Reserve. [Method] The current situation of wild plant resources in Xishuangbanna National Nature Reserve was researched by means of route survey, sample plot survey and literature survey, and then the main impact factors of wild plant resources were analyzed by using participatory rural appraisal and problem tree analysis, finally protection countermeasures were put forward according to current situation and main impact factors. [Result] There were 2 779 species of vascular plants belonging to 214 families and 1 012 genera (including subfamilies and varieties) in Xishuangbanna National Nature Reserve, among them, there existed 261 species of pteridophyte belonging to 41 families and 91 genera, 14 species of gymnosperm belonging to 6 families and 6 genera, and 2 504 species of angiosperm belonging to 167 families and 915 genera. Wild plant resources in reserve were mainly affected by planting under forest, habitat fragmentation, cutting trees, collection and utilization of no-timber products, development of animal husbandry, insufficient recognition of community residents to reserve management establishment and lots of floating population. In the future, wild plant resources in reserve could be protected through strengthening propaganda, education and management, enforcing the law strictly and other countermeasures. [Conclusion] The study could provide theoretical foundation for the protection of wild plant resources in Xishuangbanna National Nature Reserve.
文摘This article introduced the new methods on the research of the wild flowers and plants idioplasmic resources, elaborated the introduction and domestication and exploitation of wild flowers and plants idioplasmatic resources and the sustainable development of flowers and plants industry in China, and put forward some proposals on the existing question and the prospects for the development.
基金This work was supported by a grant of the National Science Fund of the Republic of Bulgaria under Project No.DN 04/1,13.12.2016 entitled:“Study of the combined effect of the natural radioactivity background,the UV radiation,the climate changes and the cosmic rays on model groups of plant and animal organisms in mountain ecosystems”.
文摘Plants in natural ecosystems are exposed to a combination of UV radiation,ionizing radiation(IR)and other abiotic factors.These factors change with the altitude.We investigated DNA alterations of some wild plants of different plant families in natural ecosystems at three altitudes in Rila Mountain,Bulgaria(1500,1782,and 2925 m above sea level(a.s.l.)exposed to UV radiation,IR and other abiotic stresses,to assess the tolerance of plant species to the changing environmental conditions in three successive growth seasons.For this purpose,physicochemical,cytogenetic,and molecular methods were applied.DNA damage was assessed by micronucleus test and molecular method comet assay adapted and applied by us to wild plant species from Onagraceae,Rosaceae,Boraginaceae,Saxifragaceae,Orobanchaceae,Asteraceae and Poaceae families,growing at three different altitudes.Variability in the DNA sensitivity and the level of tolerance was observed among the plant species in response to combined abiotic factors assessed by induced DNA damage and gross beta activity.The studied representatives of Poaceae were less susceptible than the other studied species at all three altitudes and showed close level of DNA injuries to that of unaffected control plant grown in laboratory conditions.The lower levels of DNA damage of these wild plant species corresponded to their lower ability to accumulate radionuclides.There was a particularly pronounced low level of DNA injuries in the plant species at the highest altitude.The level of DNA damage showed correlation with the values of some abiotic environmental factors.The results would contribute to the elucidation of the extent of adaptation of plant species to the continuously changing environment and would be useful in selecting sensitive herbaceous monitor species for environmental impact assessment at mountain and alpine sites.
基金financial support of the National Research Foundation (NRF 85294),South Africa
文摘Objective:To evaluate the nutritional composition and elemental constituents of Kedrostis africana and their safety aspect.Methods:Proximate parameters(moisture,ash,crude fibre,crude fat,proteins,and carbohydrate and energy) were evaluated using ALASA methods,and elemental analysis by ICP-OES technique.Results:The results from nutritional analysis showed that the tuber used for this study had a low content of crude fat and high content of ash,crude protein,crude fibre,carbohydrate and energy having the recommended dietary allowances.The tuber was rich in major minerals Na,K,Ca and Mg,there was sufficient amount of trace elements Fe,Cu,and Zn while the anti-nutrients oxalate,phytate,alkaloids,and saponins were detected in amounts that are not harmful according to Food and Agriculture Organization/World Health Organization.Conclusions:The outcome of this study suggests that this wild plant has very good nutritional potentials to meet the recommended dietary allowance and it could be a cheap source of essential nutrients that may ameliorate most nutritional challenges and can contribute remarkably to the amount of nutrient intake in human and animal diet.
基金Supported by Basic Scientific Research Business Funds of Public Welfare Scientific Research Institutes of the Autonomous Region in 2022 (kyys202201)
文摘In recent years,the protection of PSESP has gradually become a hot issue in biodiversity research.Through the investigation and analysis of PSESP in Xinjiang,it is shown that:①there are 75 species of PSESP in Xinjiang,including 22 species of trees,18 species of shrubs and 35 species of herbs.The habitats are mainly in extremely cold,extremely dry or extremely narrow conditions such as snow line,desert,mountain,wetland and so on.②53 species(70.67%)are listed as national or autonomous region protected plants,and 22 species of PSESP are not listed in the protection;there are 70 species of PSESP listed in the red list,accounting for 93.33%.③The PSESP in Xinjiang are mainly distributed in the Altai Mountains,western Tianshan Mountains,Pamir Plateau and Karakoram Mountains;they are distributed in all kinds of nature reserves,forest parks,wetland parks and other natural ecological protection areas in Xinjiang.Ammopiptanthus nanus(M.Pop.)Cheng F.,Cistanche tubulosa(Schenk)Wight,Calligonum roborovskii A.Los.and Prunus cerasifera Ehrhart have not been found in the literature,indicating that they are distributed in protected areas.In order to provide a theoretical basis for the conservation of biodiversity in Xinjiang,this paper puts forward some suggestions on the protection of PSESP.
基金supported by Grants from National Forestry and Grassland Administration,China(No.2019073018,2019073019)National Natural Science Foundation of China(No.31870195,31670194)。
文摘We review achievements in the conservation of orchid diversity in China over the last 21 years.We provide updated information on orchid biodiversity and suggestions for orchid conservation in China.We outline national policies of biodiversity conservation,especially of orchid conservation,which provide general guidelines for orchid conservation in China.There are now approximately 1708 known species of Orchidaceae in 181 genera in China,including five new genera and 365 new species described over the last 21 years.The assessment of risk of extinction of all 1502 known native orchid species in China in 2013 indicated that 653 species were identified as threatened,132 species were treated as data-deficient,and four species endemic to China were classified as extinct.Approximately 1100 species(ca.65%)are protected in national nature reserves,and another~66 species in provincial nature reserves.About 800 native orchid species have living collections in major botanical gardens.The pollination biology of 74 native orchid species and the genetic diversity and spatial genetic structure of 29 orchid species have been investigated at a local scale and/or across species distributions.The mycorrhizal fungal community composition has been investigated in many genera,such as Bletilla,Coelogyne,Cymbidium,Cypripedium,and Dendrobium.Approximately 292 species will be included in the list of national key protected wild plants this year.Two major tasks for near future include in situ conservation and monitoring population dynamics of endangered species.
文摘The seasonal fluctuation oflepidoptcran cereal stemborers on maize and wild host plants (i.e., grasses and a few sedges) was investigated in southern Benin from 1988 to 1998 by time series analysis and repeated-measures analysis of variance (ANOVA). In addition, a walk-in light trap was used to study the flight behavior of adult moths. On both cereals and grasses, the noctuid Sesamia calaraistis was the predominant species, followed by the pyralid Eldana saccharina. The noctuid Busseolafusca was rare on both maize and wild host plants. In general, pest populations increased during the course of the year to reach peak densities during the second short rainy season, and then crashed to close to zero during the dry season. On wild host plants, egg masses and other immature stages were collected throughout the year but they were higher on wild grasses than maize during the off-season. Thus wild host plants can be considered as refuge for both borers and natural enemies during the off-season, when maize is not available. However, only four out of the eleven wild host species played a discernable role. S. calamistis egg densities appeared to be influenced by density-dependent factors, suggesting an effect of natural enemies. Temperature and rainfall had a negative effect on egg abundance. Larval parasitism by a Kenyan strain of the braconid Cotesia sesamiae, which was released in southern Benin in the early 1990s, and by the tachinid Sturmiopsisparasitica varied between seasons and years but there were no discernable patterns. For both parasitoids and borer host species, parasitism was positively correlated with trap catches of adult moths. The recovery of C. sesamiae during a 2-year period suggests that the parasitoid has established its population in southern Benin.
文摘The aim of this study was to determine the allelopathic effects of <i><span style="font-family:Verdana;">Azadirachta indica</span></i><span style="font-family:Verdana;"> oil and aqueous extracts of </span><i><span style="font-family:Verdana;">Tithonia diversifolia</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Thevetia peruviana</span></i><span style="font-family:Verdana;"> on the growth and stimulation of metabolites involved in tomato plant resistance. Randomized in blocks within a shaded area, the different treatments prepared at 10% and 15% (v/v and w/v) in water were subsequently applied on tomatoes seeds to monitor the effect on germination, and on tomatoes leaves to monitor the effect on growth and resilience of the plants. The result showed that in stressful conditions all the treatment</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> significantly inhibit (p < 0.05) the germination capacity of the seeds from 21.22% to 92.61%, the germination rate from 39.82% to 92.76% and the germination viability of the seedlings from 64.67% to 100%. However, the negative allelopathic effect of the treatment was significantly reduced (p < 0.05) when used for germination initiation by botanical priming. In addition, while </span><i><span style="font-family:Verdana;">T. diversifolia</span></i><span style="font-family:Verdana;"> at 10% promotes a better aerial and root growth in tomato plants, </span><i><span style="font-family:Verdana;">T. peruviana</span></i><span style="font-family:Verdana;"> at 15% induces the activation of resistance mechanisms in tomato plants by increasing protein levels to 104.5%, phenol levels to 183.33% and peroxidase enzyme activity to 586.15%. Therefore, allelopathic compound of wild plants would be a good alternative for growth promotion and resistance of tomato crops.</span></span></span></span>
基金the West African Agricultural Productivity Program(WAAPP/TOGO)and Bill and Melinda Gates Foundation(BMGF)for supporting this project.
文摘Geminiviruses, in particular the members of the genus Begomovirus , are considered to be a major phytosanitary problem for tomato crops production in the world. They are responsible for yield losses of up to 20% to 100%. Regrettably, Togo is not spared from this situation. This work aims to show the genetic diversity of the begomoviruses affecting tomato crops production in Togo and their relationship with other begomoviruses. To achieve these objectives, 307 samples of tomato leaves and wild plant species with typical virus symptoms were collected in the Maritime, Plateaus, Central, Kara and Savannah regions and submitted to PCR analysis. The results revealed the presence of begomovirus in 25.40% of the analyzed samples. The PCR products obtained were submitted to direct sequencing. Phylogenetic analysis of sequences of DNA-A different regions of begomovirus identified in this work with that of other begomoviruses showed a nucleotide identity of 96% respectively for Tomato leaf curl Togo virus-Fontem, Tomato Leaf Curl Togo Virus , Ageratum leaf curl Cameroon Alphasatellite;98% respectively to Tomato leaf curl Nigeria virus , Ageratum leaf curl Cameroon virus , Tomato leaf curl Cameroon virus-Fontem, Ageratum leaf curl Cameroon virus and 99% respectively to Tomato leaf curl Kumasi virus , Pepper yellow vein Mali virus Bazegahot and Pepper yellow vein Mali virus-Ouaga. These results suggest a high degree of genetic diversity of tomato begomoviruses identified in Togo.