Effect of vernalization and plant growth regulators on flowering of Onithogalum ‘Chesapeake Snowflake’

The effect of vernalization and two growth regulators Fascination^TM and Pro-Gibb^R on the growth, inflorescence development and flowering of Omithogalurrt Chesapeake Snowflake＇ was studied. Regardless of growth regulator treatment, chilling bulbs for 3 weeks at 10℃ before planting accelerated flowering of the first inflorescence by 5 to 6 days, elongated floral stem length by 1.5 to 2 cm and shortened leaf length by 4 to 5 cm as compared with non-chilled bulbs. When bulbs were chilled 3 weeks at 10℃ before planting, Fascination 2% and Pro-Gibb accelerated flowering of the first inflorescence by 2 to 6 days respectively as compared with the control. When bulbs were not chilled before planting, Fascination 2% and Pro-Gibb accelerated flowering of the first inflorescence by 6 to12 days respectively as compared with the control. The lengths of the leaves and the inflorescences were not affected by PGR treatment. Higher rates of Pro-Gibb （100 mg.L^-1 and 200 mg.L^-1） and more amount of Fascination 2%（100 μL and 200 μL） can cause abortion of inflorescence.

Effect of Snow-cover Duration on Plant Species Diversity of Alpine Meadows on the Eastern Qinghai-Tibetan Plateau

Although snow cover plays an important role in structuring plant diversity in the alpine zone, there are few studies on the relationship between snow cover and species diversity of alpine meadows on the eastern Qinghai-Tibetan Plateau. To assess the effect of snow cover on plant species diversity of alpine meadows, we used ten parallel transects of 60 m × 1 m for this study and described the changes in species diversity and composition associated with snow depth. With the division of snow depth into six classes, the highest species richness （S） and species diversity （H′） occurred with an intermediate snow depth, i.e., class Ⅲ and class Ⅳ, showing a unimodal curve with the increase in snow depth. The relationship between snow depth and plant diversity （both richness and Shannon index） could be depicted by quadratic equations. There was no evident relationship between diversity （both S and H′） and soil water content, which implied that other more important factors influenced species diversity. The patterns of diversity found in our study were largely attributed to freeze-thaw alteration, length of growing season and disturbances of livestock grazing. Furthermore, snow depth affected species composition, as evaluated by the Sorensen＇s index of similarity. In addition, almost all species limited to one snow depth class were found only in class Ⅲand class Ⅳ, indicating that intermediate snow depth was suitable for the survival and growth of many alpine species.

Seedling and adult plant resistance to leaf rust in 46 Chinese bread wheat landraces and 39 wheat lines with known Lr genes

Wheat leaf rust,caused by Puccinia triticina(Pt),is an important foliar disease that has an important influence on wheat yield.The most economic,safe and effective way to control the disease is growing resistant cultivars.In the present study,a total of 46 wheat landraces and 34 wheat lines with known Lr(leaf rust resistance)genes were inoculated with 16Pt pathotypes for postulating seedling resistance gene(s)in the greenhouse.These cultivars and five wheat differential lines with adult plant resistance(APR)genes(Lr12,Lr22b,Lr34,Lr35 and Lr37)were also evaluated for identification of slow rusting resistance in the field trials in Baoding,Hebei Province of China in the 2014–2015 and 2015–2016 cropping seasons.Furthermore,10 functional molecular markers closely linked to 10 known Lr genes were used to detect all the wheat genotypes.Results showed that most of the landraces were susceptible to most of the Pt pathotypes at seedling stage.Nonetheless,Lr1 was detected only in Hongtangliangmai.The field experimental test of the two environments showed that 38 landraces showed slow rusting resistance.Seven cultivars possessed Lr34 but none of the landraces contained Lr37 and Lr46.Lr genes namely,Lr9,Lr19,Lr24,Lr28,Lr29,Lr47,Lr51 and Lr53 were effective at the whole plant stage.Lr18,Lr36 and Lr45 had lost resistance to part of pathotypes at the seedling stage but showed high resistance at the adult plant stage.Lr34 as a slowing rusting gene showed good resistance in the field.Four race-specific APR genes Lr12,Lr13,Lr35 and Lr37 conferred good resistance in the field experiments.Seven race-specific genes,Lr2b,Lr2c,Lr11,Lr16,Lr26,Lr33 and LrB had lost resistance.The 38 landraces showed slow rusting resistance to wheat leaf rust can be used as resistance resources for wheat resistance breeding in China.

Impacts of snow on seed germination are independent of seed traits and plant ecological characteristics in a temperate desert of Central Asia

Seed germination profoundly impacts plant community composition within the plant life cycle.Snow is an important source of water for seed germination in the temperate deserts of Central Asia.Understanding how seed germination responds to variations in snow cover in relation to seed traits and plant ecological characteristics can help predict plant community sustainability and stability in Central Asia under a scenario climate change.This study investigated the seed germination of 35 plant species common to the Gurbantunggut Desert in Central Asia under the three snow treatments:(1)snow addition;(2)ambient snow;and(3)snow removal.Two-way analysis of variance(ANOVA)tests were performed to assess interactions among the impacts of snow treatments,seed traits and plant ecological characteristics on seed germination.Phylogenetic generalized least-squares(PGLS)model was used to test the relationships between seed traits and seed germination.The results demonstrated that snow variations had no significant impacts on seed germination overall.Seed germination under the snow addition treatment was similar with that under the ambient snow treatment,irrespective of seed traits and plant ecological characteristics.Snow removal only had negative impacts on seed germination for certain groups of seed traits and plant ecological characteristics.Seed mass positively affected seed germination,showing a linear increase of arcsin square root-transformed seed germination with log-transformed seed mass.Seed shape also profoundly impacted seed germination,with a higher germination percentage for elongated and flat seeds.Seed germination differed under different plant life forms,with semi-shrub species showing a significantly higher germination percentage.Most importantly,although snow treatments,seed traits and plant ecological characteristics had no interactive effects on seed germination overall,some negative impacts from the snow removal treatment were detected when seeds were categorized on the basis of seed mass and shape.This result suggests that variations of snow cover may change plant community composition in this temperate desert due to their impacts on seed germination.

Traditional knowledge, use and conservation of plants by the communities of Tharaka-Nithi County, Kenya

Rural communities in Kenya largely depend on plant resources for their livelihood.The utilization of these resources depends on the availability of plant resources and the level of knowledge of the residents.We conducted an ethnobotanical study in Tharaka-Nithi County in Kenya to determine the knowledge and utilization of various plant species by the local communities.The study was conducted in four major administrative regions from June 2018 to February 2019,involving interview schedules using semi-structured open-ended questionnaires and guided field collections with 48 informants.A total of 214 plant species distributed in 73 families and 169 genera with 616 Use Reports(URs)were documented.Fabaceae was the highest family cited by the informants(31 species)followed by Lamiaceae and Euphorbiaceae(each with 11 species).Trees(49%)and shrubs(32%)were the top life forms of the plants frequently utilized by the local residents.The general plant uses reported were medicinal,food,fodder,construction,fuel,pesticidal,religious,live fencing,and making crafts.Zanthoxylum gilletii,Prunus africana,and Solanum incanum were found to be highly valued by the local communities.Plant utilization as food and medicinal uses against snake-bite related problems had the highest Informant Consensus Factor(ICF).Only 29(13.6%)of the species reported had their status assessed by the International Union for Conservation of Nature(IUCN).Conservation measures,alongside awareness creation in this region,are highly recommended for the species endemic to the region,highly depended on by the community,and those threatened according to IUCN standards.

In Vitro Antifungal Activity of the Extract and Compound from Acorus tatarinowii Against Seven Plant Pathogenic Fungi

Acorus tatarinowii Schott is a traditional Chinese medicine plant and has multiple bioactivities in medicine and pesticide field. In this study, the antifungal compound 1,2-dimethoxy-4（2-propenyl） benzene was isolated from A. tatarinowii Schott by activity-directed isolation method, and the inhibitory activity of the extract and 1,2-dimethoxy-4（2-propenyl） benzene against seven plant pathogenic fungi was evaluated. The results showed that the extract and 1,2-dimethoxy-4（2- propenyl） benzene had high inhibitory activity against hyphal growth of Thielaviopsis paradoxa （de Seynes） V. Hohnel, Pestalotia mangiferae P. Henn., Fusarium oxysporum f. sp. niveum （E. F. Smith） Syn. et Hans., Alternaria alternate Tanaka, Colletotrichum musae （Berk et Curt） V. Arx, Sphaceloma fawcettii Jenk., and Mycosphaerella sentina （Fr.） Schroter. The EC50 values of extract were 1.6162, 1.6811, 1.1253, 3.5771, 1.7024, 2.2284, and 2.2221 g L^-1, respectively, and the EC50 values of 1,2-dimethoxy-4（2-propenyl） benzene were 0.1021, 0.0997, 0.0805, 0.1742, 0.1503, 0.1853, and 0.1924 g L^-1, respectively. 1,2-Dimethoxy-4（2-propenyl） benzene also inhibited spores germination of T. paradoxa （de Seynes） V. Hohnel and F. oxysporum f. sp. niveum （E. F. Smith） Syn. et Hans., with the inhibitory rates of 98.81 and 100% at a concentration of 0.4 g L^-1 after 8 h, respectively. 1,2-Dimethoxy-4（2-propenyl） benzene is a potential botanical antifungal agent for controling of plant fungal diseases.

Local Knowledge on Plants and Domestic Remedies in the Mountain Villages of Peshkopia(Eastern Albania)

Ethnobotanical studies in the Balkans are crucial for fostering sustainable rural development in the region and also for investigating the dynamics of change of Traditional Ecological Knowledge(TEK),which has broad-sweeping implications for future biodiversity conservation efforts.A survey of local botanical and medical knowledge and practices was conducted in four mountainous villages of the Peshkopia region in northeast Albania,near the Macedonian border.Snowball sampling techniques were employed to recruit 32 informants for participation in semi-structured interviews regarding the use of the local flora for food,medicinal,veterinary and ritual purposes.The uses of 84 botanical taxa were recorded as well as a number of other folk remedies for the treatment of both humans and livestock.Comparison of the collected data with another ethnobotanical field study recently conducted among Albanians living on the Macedonian side of Mount Korab shows a remarkable divergence in medicinal plant uses,thus confirming the crucial role played by the history of the last century in transforming TEK.Most noteworthy,as a legacy of the Communist period,a relevant number of wild medicinal taxa are still gathered only for trade rather than personal/familial use.This may lead to unsustainable exploitation of certain taxa(i.e.Orchis and Gentiana spp.) and presents some important conservation challenges.Appropriate development and environmental educational frameworks should aim to reconnect local people to the perception of limitation and renewability of botanical resources.

Compatibility and complementarity of indigenous and scientific knowledge of wild plants in the highlands of southwest Saudi Arabia

This study presents a survey of wild plants commonly used by local inhabitants in the highlands of southwest Saudi Arabia. Based upon literature review, direct observation of local inhabitants, and questionnaire interviews, 36 plant species were assessed and given scores according to their use. The gaps between scientific and indigenous knowl- edge on the use of plants were estimated using a ＂compatibility ratio＂. The score values were estimated based on seven different use categories of ecosystem services, including food, forage, medicine, wood, beekeeping, research, and education. Additional structural categories include source of materials, shade, hedges, ornamental plantings, and soil stabilization. There are discrepancies between indigenous knowledge （IK） and scien- tific knowledge （SK） but in most cases, SK of the species supports the IK and plant users preference. The results also provide information that challenges assumptions about the consistency of IK with SK. Our study highlights the importance of understanding the cultural context and uses of wild plants. Biodiversity-based knowledge holds promise for contributing to sustainable use of wild plant resources and related traditions. The success of such endeavours depends on the compatibility and complementarity of indigenous and scientific knowledge.

Chinese Plants in the Persian Agricultural Manual Asar va Ahyā’,and a Discussion of Rashīd al-Dīn’s Chinese Knowledge and Agricultural Practice

The Asar va Ahyā’is a manual of agricultural production written in the early fourteenth century by the famous Iranian vizier and scholar Rashīd al-Dīn.Only chapter 6 to chapter 13 of the original work survive,dealing with agriculture and horticulture,and nearly a third of the pages of which are devoted to introducing Chinese plants and related knowledge.In addition to introducing botanical knowledge,the book also covered information on all the aspects of the Yuan dynasty(1271–1368),including the taxation system,monetary system,military system,economy and trade,manufacturing techniques,ethnic customs,food culture,and other fields,providing important materials for research on the dissemination of species,exchange of technologies,communication of ethnic groups,and integration of cultures between China and the world during the thirteenth and fourteenth centuries.Rashīd al-Dīn,the book’s author,took advantage of his identities as a statesman and a businessman to collect rich information about plants all over the world.Motivated by his specific interest in Chinese culture,he included a huge amount of Chinese information in the book.Meanwhile,records in the Asar va Asyā’reflect the author’s practice of researching,planting,and cultivating plants,making the book not only a compilation of agricultural knowledge,but also a report that recorded the author’s agricultural practice.

Ethnobotanical and Indigenous Knowledge of Important Plants in East Hararghe, Eastern Ethiopia

An ethnobotanical study was conducted in East Hararghe, Ethiopia to identify and investigate the use of various plants by the traditional healers and communities engaged in domestic, pesticide and medicinal use. A total of 78 species were observed to be used by the local inhabitants in the region for the treatments of various ailments. Out of these, herbs constitute 49% followed by trees(36%) and shrubs only 15%. However, most frequently used plant parts were leaf and aerial parts(20) followed by seed(13), fruit(12), other parts(10), rhizome(7) and bark(1). Most of the plants were found to be used for medicinal, aromatic and food flavouring(spices, condiments) purposes. Out of 78 species recorded in the present study, 11 were reported to cure stomachache, seven for cold, cough and respiratory problem, six for diarrhoea and five species were found capable of curing fever. Fabaceae was the largest family contributing to medicinal plant use with seven species followed by Solanaceae, Myrtaceae,(5 spp.), and Zingiberaceae, Asteraceae, Liliaceae(4 spp. each). Some of the important plants utilized for taking care of variety of ailments are Azadirachta indica, Brassica nigra, Balanites aegyptiaca, Maytenus ovatus, Rosmarinus officinalis and Trigonella foenum graecum. Most of these medicinal and aromatic plants(MAPs) play a significant role in the household economy and were observed to be very popular among the people. Unpopular plants were left out of the study. This study provides useful and basic information on usage of different plants for conducting further studies aimed at conservation and documentation of traditional medicine system and economic welfare of rural peoples of the East Hararghe, Ethiopia. It also revealed that indigenous practices contributed to sustainable management of plants.

Grain yield and N uptake of maize in response to increased plant density under reduced water and nitrogen supply conditions

The development of modern agriculture requires the reduction of water and chemical N fertilizer inputs.Increasing the planting density can maintain higher yields,but also consumes more of these restrictive resources.However,whether an increased maize density can compensate for the negative effects of reduced water and N supply on grain yield and N uptake in the arid irrigated areas remains unknown.This study is part of a long-term positioning trial that started in 2016.A split-split plot field experiment of maize was implemented in the arid irrigated area of northwestern China in 2020 to 2021.The treatments included two irrigation levels:local conventional irrigation reduced by 20%(W1,3,240 m^(3)ha^(-1))and local conventional irrigation(W2,4,050 m^(3)ha^(-1));two N application rates:local conventional N reduced by 25%(N1,270 kg ha^(-1))and local conventional N(360 kg ha^(-1));and three planting densities:local conventional density(D1,75,000 plants ha^(-1)),density increased by 30%(D2,97,500 plants ha-1),and density increased by 60%(D3,120,000 plants ha^(-1)).Our results showed that the grain yield and aboveground N accumulation of maize were lower under the reduced water and N inputs,but increasing the maize density by 30% can compensate for the reductions of grain yield and aboveground N accumulation caused by the reduced water and N supply.When water was reduced while the N application rate remained unchanged,increasing the planting density by 30% enhanced grain yield by 13.9% and aboveground N accumulation by 15.3%.Under reduced water and N inputs,increasing the maize density by 30% enhanced N uptake efficiency and N partial factor productivity,and it also compensated for the N harvest index and N metabolic related enzyme activities.Compared with W2N2D1,the N uptake efficiency and N partial factor productivity increased by 28.6 and 17.6%under W1N1D2.W1N2D2 had 8.4% higher N uptake efficiency and 13.9% higher N partial factor productivity than W2N2D1.W1N2D2 improved urease activity and nitrate reductase activity by 5.4% at the R2(blister)stage and 19.6% at the V6(6th leaf)stage,and increased net income and the benefit:cost ratio by 22.1 and 16.7%,respectively.W1N1D2 and W1N2D2 reduced the nitrate nitrogen and ammoniacal nitrogen contents at the R6 stage in the 40-100 cm soil layer,compared with W2N2D1.In summary,increasing the planting density by 30% can compensate for the loss of grain yield and aboveground N accumulation under reduced water and N inputs.Meanwhile,increasing the maize density by 30% improved grain yield and aboveground N accumulation when water was reduced by 20% while the N application rate remained constant in arid irrigation areas.

基于Plant Simulation的化纤自动落丝系统仿真实验分析

基于Plant Simulation软件,构建一种化纤自动落丝系统的3D数字化模型,对系统效率关键输入因子进行参数化设置,将系统各工位三维数字模型导入软件中建立层次化运动机构图形结构,并运用Simltalk语言实现三维动作仿真,通过基础物理参数设置,保证了仿真数字化模型与现实系统更具一致性。通过多级实验设计分析了系统影响因子对于系统效率的影响特性曲线,并进一步通过动态参数化实验方法,计算出双输入因子对系统效能影响的敏感度。该实验结果可为化纤自动落丝系统的建设成本控制与可行性分析提供指导,具有较好的工程应用价值。

基于Plant Simulation的压气机叶片型线加工产线分析与优化

运用专业仿真软件Plant Simulation,根据压气机叶片型线机械加工工艺特点和物料运行流程建立生产线仿真模型,从产能、设备利用率及产线瓶颈等多方面进行仿真分析与优化。结果表明:Plant Simulation仿真平台的仿真可以找出规划设计方案中存在的问题并验证方案的合理性。该仿真结果为型线机械加工产线的优化设计提供了可靠依据,达到了节约投资成本和缩短设计周期的目的。

GmSTF accumulation mediated by DELLA protein GmRGAs contributes to coordinating light and gibberellin signaling to reduce plant height in soybean

Plant height influences plant architecture,lodging resistance,and yield performance.It is modulated by gibberellic acid(GA)metabolism and signaling.DELLA proteins,acting as central repressors of GA signaling,integrate various environmental and hormonal signals to regulate plant growth and development in Arabidopsis.We examined the role of two DELLA proteins,GmRGAa and GmRGAb,in soybean plant height control.Knockout of these proteins led to longer internodes and increased plant height,primarily by increasing cell elongation.GmRGAs functioned under different light conditions,including red,blue,and far-red light,to repress plant height.Interaction studies revealed that GmRGAs interacted with the blue light receptor GmCRY1b.Consistent with this,GmCRY1b partially regulated plant height via GmRGAs.Additionally,DELLA proteins were found to stabilize the protein GmSTF1/2,a key positive regulator of photomorphogenesis.This stabilization led to increased transcription of GmGA2ox-7b and subsequent reduction in plant height.This study enhances our understanding of DELLA-mediated plant height control,offering Gmrgaab mutants for soybean structure and yield optimization.

Regulation of 2-acetyl-1-pyrroline and grain quality in early-season indica fragrant rice by nitrogen and silicon fertilization under different plantation methods

Fragrant rice has a high market value,and it is a popular rice type among consumers owing to its pleasant flavor.Plantation methods,nitrogen(N)fertilizers,and silicon(Si)fertilizers can affect the grain yield and fragrance of fragrant rice.However,the core commercial rice production attributes,namely the head rice yield(HRY)and 2-acetyl-1-pyrroline(2-AP)content of fragrant rice,under various nitrogen and silicon(N-Si)fertilization levels and different plantation methods remain unknown.The field experiment in this study was performed in the early seasons of 2018 and 2019 with two popular indica fragrant rice cultivars(Yuxiangyouzhan and Xiangyaxiangzhan).They were grown under six N-Si fertilization treatments(combinations of two levels of Si fertilizer,0 kg Si ha^(−1)(Si0)and 150 kg Si ha^(−1)(Si1),and three levels of N fertilizer,0 kg N ha^(−1)(N0),150 kg N ha^(−1)(N1),and 220 kg N ha^(−1)(N2))and three plantation methods(artificial transplanting(AT),mechanical transplanting(MT),and mechanical direct-seeding(MD)).The results showed that the N-Si fertilization treatments and all the plantation methods significantly affected the HRY and 2-AP content and related parameters of the two different fragrant rice cultivars.Compared with the Si0N0 treatment,the N-Si fertilization treatments resulted in higher HRY and 2-AP contents.The rates of brown rice,milled rice,head rice,and chalky rice of the fragrant rice also improved with the N-Si fertilization treatments.The N-Si fertilization treatments increased the activities of N metabolism enzymes and the accumulation of N and Si in various parts of the fragrant rice,and affected their antioxidant response parameters.The key parameters for the HRY and 2-AP content were assessed by redundancy analysis.Furthermore,the structural equation model revealed that the Si and N accumulation levels indirectly affected the HRY by affecting the N metabolism enzyme activity,N use efficiency,and grain quality of fragrant rice.Moreover,high N and Si accumulation directly promoted the 2-AP content or affected the antioxidant response parameters and indirectly regulated 2-AP synthesis.The interactions of the MT method with the N-Si fertilization treatments varied in the fragrant rice cultivars in terms of the HRY and 2-AP content,whereas the MD method was beneficial to the 2-AP content in both fragrant rice cultivars under the N-Si fertilization treatments.

WPA1 encodes a vWA domain protein that regulates wheat plant architecture

Plant height,spike,leaf,stem and grain morphologies are key components of plant architecture and related to wheat yield.A wheat(Triticum aestivum L.)mutant,wpa1,displaying temperaturedependent pleiotropic developmental anomalies,was isolated.The WPA1 gene,encoding a von Willebrand factor type A(vWA)domain protein,was located on chromosome arm 7DS and isolated by map-based cloning.The functionality of WPA1 was validated by multiple independent EMS-induced mutants and gene editing.Phylogenetic analysis revealed that WPA1 is monocotyledon-specific in higher plants.The identification of WPA1 provides opportunity to study the temperature regulated wheat development and grain yield.

Sex-specific facilitation and reproduction of the gynodioecious cushion plant Arenaria polytrichoides on the Himalaya-Hengduan mountains,SW China

When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytrichiodes as a model species,we aimed to assess the sex-specific facilitation intensity of cushion plant by measuring the beneficiary cover ratio,and to assess the potential costs in cushion reproductive functions by measuring the flower and fruit cover ratios.The total beneficiary cover ratio was similar between females and hermaphrodites.Females produced much less flowers but more fruits than hermaphrodites.These results suggested that females and hermaphrodites possess similar facilitation intensity,and female cushion A.polytrichoides may allocate more resources saved from pollen production to seed production,while hermaphrodites possibly allocate more resources to pollen production hence reducing seed production.The surface areas covered by beneficiaries produced less flowers and fruits than areas without beneficiaries.In addition,strong negative correlations between beneficiary cover and flower cover were detected for both females and hermaphrodites,but the correlation strength were similar for these two sex morphs.However,the correlation between beneficiary cover and fruit cover was only significantly negative for females,suggesting that beneficiary plants negatively affect fruit reproduction of females while have neutral effects on hermaphrodites.All the results suggest that to facilitate other beneficiaries can induce reproductive costs on cushion A.polytrichoides,with females possibly suffering greater cost than hermaphrodites.Such differentiation in reproductive costs between sex morphs,in long-term perspective,may imply sex imbalance in population dynamics.

Increased dependence on nitrogen-fixation of a native legume in competition with an invasive plant

Suppression of roots and/or their symbiotic microorganisms,such as mycorrhizal fungi and rhizobia,is an effective way for alien plants to outcompete native plants.However,little is known about how invasive and native plants interact with the quantity and activity of nutrient-acquisition agents.Here a pot experiment was conducted with monoculture and mixed plantings of an invasive plant,Xanthium strumarium,and a common native legume,Glycine max.We measured traits related to root and nodule quantity and activity and mycorrhizal colonization.Compared to the monoculture,fine root quantity(biomass,surface area)and activity(root nitrogen(N)concentration,acid phosphatase activity)of G.max decreased in mixed plantings;nodule quantity(biomass)decreased by 45%,while nodule activity in Nfixing via rhizobium increased by 106%;mycorrhizal colonization was unaffected.Contribution of N fixation to leaf N content in G.max increased in the mixed plantings,and this increase was attributed to a decrease in the rhizosphere soil N of G.max in the mixed plantings.Increased root quantity and activity,along with a higher mycorrhizal association was observed in X.strumarium in the mixed compared to monoculture.Together,the invasive plant did not directly scavenge N from nodule-fixed N,but rather depleted the rhizosphere soil N of the legume,thereby stimulating the activity of N-fixation and increasing the dependence of the native legume on this N source.The quantity-activity framework holds promise for future studies on how native legumes respond to alien plant invasions.

Plant diversity in herbal tea and its traditional knowledge in Qingtian County, Zhejiang Province, China

Herbal teas composed of locally occurring plant species have long been used as the primary form of health care in Qingtian County,Zhejiang Province,China.However,large-scale emigration overseas and an aging population threaten the conservation of traditional knowledge of these herbal teas.Traditional knowledge about the plants used for these herbal teas is not well documented in Qingtian,despite their widespread use.The aim of this study was to assess the plant-cultural diversity of plants used as herbal teas,and to point out the prospective value of herbal teas used by Qingtian people.This study was conducted using semi-structured interviews,as well as field and market surveys.Forty-three local informants were interviewed.We recorded plant resources,plant parts used,local names,and medicinal uses.Quantitative ethnobotanical indices,including cognitive salience(CS),frequency of citation(FC),index of informant consensus(Fic)and use value(UV),were calculated to analyze the level of representativeness and relative importance of plants used in herbal teas.One hundred and twenty-nine species belonging to 75 families and 113 genera were reported to be used in herbal tea,with Compositae being the richest family.Whole plants are most commonly used to make herbal teas(66.7%).In this study,informants reported that 92.2%of plant species used in herbal teas are wild.The most utilized herbal preparation form is dry/fresh.Informants reported that herbal teas are used to treat 31 ailments.Our results show that the highest representativeness,based on CS and FC,was recorded for species Actinidia eriantha.Based on UV,the top five most used species are Goodyera schlechtendaliana,Plantago asiatica,Prunella vulgaris,Lophatherum gracile and Leonurus japonicus.The highest Fic was cited for dental medicine.This study helps document the status of current herbal teas in Qingtian.The use value and traditional knowledge of herbal teas have provided basic data for further research focused on bioactivity studies and sustainable utilization of the most important species.

PSA study of the effect of extreme snowfall on a floating nuclear power plant:case study in the Bohai Sea

This study presents a probabilistic safety analysis(PSA)method for the external event of extreme snowfall on a floating nuclear power plant(FNPP)deployed in the Bohai Sea.We utilized the Weibull and Gumbel extreme value distributions to fit the collected meteorological data and obtained a hazard curve for the event of an extreme snowfall where the FNPP is located,providing a basis for the frequency of extreme snowfall-initiating events.Our analysis indicates that extreme snowfall primarily affects the ventilation openings of the equipment,leading to the failure of devices such as the diesel generators.Additionally,extreme snowfall can result in a loss of off-site power(LOOP).Therefore,the developed extreme snowfall PSA model is mainly based on the LOOP event tree,considering responses such as snowfall removal by personnel.Our calculations indicate a core damage frequency(CDF)of 1.13×10^(-10) owing to extreme snowfall,which is relatively low.The results of the cut-set analysis indicate that valve failures in the core makeup tank(CMT),passive residual heat removal system(PRS),and in-containment refueling water storage tank(IRWST)significantly contribute to the CDF.