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1.
The objective of our study was to lay a foundation for the effect of flower fragrance on human emotions and to provide a theory for the choice of indoor plants and the improvement of the olfactory environment. Specifically, our purpose was to study human physiological responses to flower fragrance of Lilium ‘Siberia’ and Rosa ‘Escimo’. The participants were 31 college students. Blood pressure, pulse rate, finger temperature (FT) and galvanic skin response (GSR) were measured. The results show that the fragrance of Rosa ‘Escimo’ causes the diastolic pressure and pulse rate of the participants to reduce significantly. The average decrease was 0.37 kPa and 2.23 beats per minute, which indicates that sympathetic nervous activity increases, physiological arousal decreases and emotional alleviation occurs. Furthermore, the GSR of participants significantly increased by smelling the fragrance of Lilium ‘Si-beria’, indicating that both sympathetic nervous activity and physiological arousal increased. But the data could not prove that flower fragrance stimulation has an effect on changes in systolic pressure and finger temperature. Some other factors, such as basic emotion and weather, may have an effect.  相似文献   

2.
The tissue-cultured seedlings of tree peony ‘Wulong Pengsheng’ were used to study the effects of different plant growth regulators, culture methods, and holdfast on rooting. The morphological structure change during rooting was also observed using the method of paraffin section. The result showed that the best combination of plant growth regulators for rooting was IBA 3.0 mg·L-1 + NAA 0.6 mg·L-1. The treatment under the temperature of 4℃ for ten days was benefit to rooting, and the rate could reach 75.67%. It was identified that the adventitious root primordia of shoot in vitro originated from the vascular cambium cells, especially, the cross areas of cambium and pith ray and they started to differentiate at the 5th day and lasted to the 12th day. If the shoots were cultured in the root inducing medium for 12 days, it would lead to not only descend of rooting rate, but also showing callus of stem base, and leaf senescent. However, if they were transferred into the medium without hormone in time, the root primordial protruded the epidermis and developed normally after 5 days’ culture.  相似文献   

3.
Camellia oleifera Abel.is an important economic tree species of southern China.In this study,we evaluated the mating system and genetic diversity of a series of cultivars of C.oleifera‘Ruan Zhi’.A total of 159 individuals from the progenies of four cultivars were tested by simple sequence repeat molecular markers.Results reveal that 11 pairs of primers showed polymorphism and their polymorphism information content value was greater than 0.73,suggesting that these primers could be used to identify the genetic diversity of open-pollinated populations.The average number of effective alleles(Ne=4.88)was significantly different from the average number of alleles(Na=12.18),and their distribution in the sample population was not uniform.The average observed heterozygosity(Ho=0.96)was greater than the average expected heterozygosity(He=0.79),and the population heterozygote was excessive.Shannon index was 1.84 and populations showed high genetic diversity.As regards to the mating system,the multilocus outcrossing rate was 0.996,and the single locus 0.866.These results indicate a high degree of outcrossing by C.oleifera‘Ruan Zhi’.We recommend selecting individuals for high genetic gain from the progenies of cultivars because of outcrossing characteristics and genetic diversity for application to germplasm conservation and promotion.  相似文献   

4.
Compared with the species of Leuce section,the difficulty in plant regeneration during tissue culture for the species of Aigeiros section is a key limiting factor for their application in genetic engineering of forest trees.In this study,the plant growth regulators combination,copper concentration,light intensity,and the selection pressures of kanamycin were investigated using leaves of Populus×euramericana cl.’Bofeng’ as explants,and a stable and high efficient regeneration system was established.Using this system,both the shoot regeneration rate and rooting rate were up to 100%,and the average number of differentiated shoots in each leaf explant was up to 20,and the survival rate of seedlings reached 98%.The optimal selection pressure of kanamycin in shoot inducement for leaf-explant was 40 mg·L-1,and the optimal selection pressure of kanamycin in root inducement of adventitious bud was 20 mg·L-1.The authors also found that differentiation rate of adventitious buds of P.×euramericana cl.’Bofeng’ could be significantly promoted by increased copper concentration,and this is the first report about the key role of copper(Cu) in explant regeneration of Poplars.This regeneration system with high frequency which was established by the authors was as good as that of species of Leuce section,and it provides a good technological platform for genetic engineering of forest tree which uses the species of Aigeiros section as model materials.  相似文献   

5.
Auxin polar transport genes PIN(PINFORMED)determine the concentration gradient of auxin in plants.To understand the relationship between the development of different tissues in Betula pendula‘Dalecartica’,BpPIN gene expression and indole-3-acetic acid(IAA)content were analyzed using qRT-PCR,ELISA,and GUS staining.Gene expression of BpPIN genes and IAA levels in the leaves,buds,stems,xylem,and roots of B.pendula‘Dalecartica’and B.pendula as a control were measured.BpPIN1,BpPIN5 and BpPIN6 were upregulated during development in both species,suggesting a dominant role in the development of B.pendula‘Dalecartica’leaves.Moreover,BpPIN1 gene expression was positively associated with IAA levels during leaf,vein and petiole development in B.pendula‘Dalecartica’only.The correlation coefficient of the first three leaves was 0.69(P=0.04),while that of the first three petioles was 0.85(P=0.001).In addition,GUS staining of the pro-DR5::GUS transgenic line of cultivar was correlated with the results of BpPIN1 expression.Overall,these findings suggest that BpPIN1 is associated with the formation of lobed leaves in B.pendula‘Dalecartica’.  相似文献   

6.
The declines in soil fertility and productivity in continuously cropped poplar plantations are related to phenolic acid accumulation in the soil.Nitrogen is a vital life element for poplar and whether the accumulation of phenolic acid could influence nitrogen metabolism in poplar and thereby hinder continuous cropping is not clear.In this study, poplar cuttings of Populus × euramericana‘Neva’ were potted in vermiculite, and phenolic acids at three concentrations(0 X, 0.5 X and 1.0 X) were added according to the actual content(1.0 X) in the soil of a second-generation poplar plantation.Each treatment had eight replicates.We measured gas exchange parameters and the activities of key enzymes related to nitrogen metabolism in the leaves.Leaf photosynthetic parameters varied with the concentration of phenolic acids.The net photosynthetic rate(P_N) significantly decreased with increasing phenolic acid concentration, and non-stomatal factors might have been the primary limitation for P_N.The activities of nitrate reductase(NR), glutamine synthetase(GS) and glutamate synthase(GOGAT), as well as the contents of nitrate nitrogen, ammonium nitrogen, and total nitrogen in the leaves decreased with increasing phenolic acid concentration.This was significantly and positively related to P_N(P0.05).The low concentration of phenolic acids mainly affected the transformation process of NO_3~- to NO_2~-, while the high concentration of phenolic acids affected both processes, where NO_3~- was transferred to NO_2~- and NH_4~+ was transferred to glutamine(Gln).Overall, phenolic acid had significant inhibitory effects on the photosynthetic productivity of Populus × euramericana‘Neva’.This was probably due to its influence on the activities of nitrogen assimilation enzymes, which reduced the amount of amino acids that were translated into protein and enzymes.Improving the absorption and utilization of nitrogen by plants could help to overcome the problems caused by continuous cropping.  相似文献   

7.
Arbuscular mycorrhizal fungi(AMF)in the soil encompass a diversity of species and play an important role in maintaining ecosystem balance.However,little research has focused on the AMF diversity of Rosa acicularis Lindl.’Luhe’,which has been cultivated in northeastern saline areas,because of its strong salt tolerance and cold resistance.In the present study the AMF in the rhizosphere of R.acicularis Luhe were identified and AMF diversity and community composition were assessed using morphological and molecular techniques.Vesicles,hyphae,and arbuscular structures were observed in seedlings of different ages.Result shows that AMF established a good symbiotic relationship with R.acicularis Luhe.The colonization rate and spore density tended to increase over time.The AMF diversity in the rhizosphere of R.acicularis Luhe was low and four species of AMF were validated:Rhizophagus irregularis,Glomus aggregatum,Septoglomus furcatum,and Funneliformis mosseae.Of these,R.irregularis and G.aggregatum were dominant and have high salt tolerance.Determining the AMF diversity in the rhizosphere of R.acicularis Luhe will aid in screening AMF species with strong resistance and using mycorrhizas for plant establishment in breeding programs.  相似文献   

8.
Different concentrations of jasmonic acid(JA)and benzothiadiazole(BTH) were sprayed on 2-year-old Rosa rugosa‘Plena’ seedlings. The induced resistance of JA and BTH to Sphaerotheca pannosa(Wallr.) and the changes of their related physiological indices were investigated. Results showed that JA and BTH treatments had inhibitory impacts on S. pannosa infection. The optimal concentration of JA and BTH was 0.5 mmol/L for the disease-resistance induction of the leaves, its inductive effect was up to 66.36% for BTH and 54.49% for JA. Our results confirmed that exogenous JA and BTH significantly improved R. rugose ‘Plena’ resistance to S. pannosa. When treated with JA and BTH, activities of the three defense enzymes(POD, PPO, and PAL) increased significantly.Contents of total phenolics, flavonoids, and lignin also increased significantly. It is inferred from these results that exogenous JA and BTH could improve the resistance of R.rugose ‘Plena’ to S. pannosa through enhancing activities of the defensive enzymes and accumulation of secondary metabolites in the leaves.  相似文献   

9.
Commercial farming of anuran species that are declining in the wild raises a need to discriminate wild from farmed frogs.We hypothesized wild frogs might have extended hindlimbs due to greater frequency or intensity of jumping relative to farmed frogs,highlighting a morphometric approach to discrimination of wild from farmed frogs using hindlimb length.In the present study,Dybowski’s frog(Rana dybowskii) was used to test this hypothesis.We measured body mass(Mb) and hindlimb length(Lh) of 2-year old farmed frogs and wild frogs aged 2 to 5 years.Dybowski’s frog demonstrated significant dimorphism in Mb and Lh.Mb was significantly greater among farmed 2-year old frogs in both sexes(p=0.000),while only among females was Lh significantly greater for wild frogs(p=0.000).Lh/Mb was used as an index for origin discrimination to eliminate the influence of Mb due to variation of husbandry conditions among farms.Mean Lh/Mb for farmed frogs was significantly lower than for wild frogs(p=0.000) in the 2-year old age class.Discrimination correctly classified 84.4% of farmed and 96.3% of wild male frogs.Among females,92.9% of farmed frogs and 90.1% wild frogs were correctly classified.The overall correctness of classification was 92.1% and 90.8% for males and females,respectively.However,Lh/Mb revealed variation with age,resulting in reduced discriminative power for frogs ≥3 years old.We introduced a coefficient Ce to adjust the Lh/Mb of frogs ≥3 years to the level equivalent to 2-year frogs.The adjustment achieved 89.5% for overall correctness of origin for wild males and 92.4% for wild females ≥3 years old.These results show that Lh/Mb is an effective index to discriminate wild from farmed Dybowski’s frog.Since the physical demands of jumping are common among anurans,this index is also potentially applicable to other anuran species.  相似文献   

10.
Climate change is a real, pressing and significant global problem. The concept of ‘climate change vulnerability’ helps us to better comprehend the cause/effect relationships behind climate change and its impact on human societies, socioeconomic sectors, and physiographical and ecological systems. In this study, multifactorial spatial modelling evaluated the vulnerability of a Mediterranean forest ecosystem to climate change and variability with regard to land degradation. This produced data and developed tools to support better decision-making and management. As a result, the geographical distribution of Environmental Vulnerability Areas(EVAs) of the forest ecosystem is the estimated Environmental Vulnerability Index(EVI) values. These revealed that, at current levels of environmental degradation, physical, geographical, policy enforcement, and socioeconomic conditions, the area with a ‘‘very low’’ degree of vulnerability covered mainly the town, its surrounding settlements and agricultural lands found principally over the low, flat travertine plateau and the plains to the east and southeast of the district. The spatial magnitude of the EVAs of the forest ecosystem under current environmental degradation was also determined. This revealed that the EVAs classed as ‘‘very low’’accounted for 21% of the area of the forest ecosystem,those classed as ‘‘low’’ for 36%, those classed as ‘‘medium’’ for 20%, and those classed as ‘‘high’’ for 24%.  相似文献   

11.
Under artificially-simulated complex salt-alkali stress, the levels of active oxygen metabolism in roots were studied using three-year-old cutting seedlings of Spiraea × bumalda ’Gold Mound’ and Spiraea × bumalda ’Gold Flame’. The present study aimed at exploring the antioxidant capacity in roots of spiraeas and revealing their adaptability to salt-alkali stress. Results indicate that the oxygen free radicals contents, electrolyte leakage rates and MDA contents in roots of Spiraea × bumalda ’Gold Mound’ and Spiraea × bumalda ’Gold Flame’ show an increasing tendency with the increases of the salinity and pH value, whereas the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) all increased firstly and then decreased. With the increase in intensity of salt-alkali stress, the CAT activity in roots of Spiraea × bumalda ’Gold Flame’ is higher and the increasing extents in the oxygen free radicals contents, electrolyte leakage rates as well as MDA contents are lower compared with Spiraea × bumalda ’Gold Mound’, indicating that Spiraea × bumalda ’Gold Flame’ has a stronger antioxidant capacity.  相似文献   

12.
Relationships between diameter at breast height(dbh) versus stand density, and tree height versus dbh(height curve) were explored with the aim to find if there were functional links between correspondent parameters of the relationships, exponents and intercepts of their power functions. A geometric model of a forest stand using a conic approximation suggested that there should be interrelations between correspondent exponents and intercepts of the relationships. It is equivalent to a type of ‘relationship between relationships’ that might exist in a forest stand undergoing self-thinning, and means that parameters of one relationship may be predicted from parameters of another. The predictions of the model were tested with data on forest stand structure from published databases that involved a number of trees species and site quality levels. It was found that the correspondent exponents and intercepts may be directly recalculated from one another for the simplest case when the total stem surface area was independent of stand density. For cases where total stem surface area changes with the drop of density, it is possible to develop a generalization of the model in which the interrelationships between correspondent parameters(exponents and intercepts) may be still established.  相似文献   

13.
Idaho locust (Robinia pseudoacacia ‘Idaho’) is an exotic multi-purpose tree used in landscaping, soil and water conservation, fodder sources and others. To improve its drought tolerance for reclaiming arid land, five lines of transformed mtl-D gene, as osmotic regulator in plant cells, have been selected and managed to determine their drought tolerance under experimental conditions. Qualitative and quantitative variables of transformed plants were studied. The critical value of drought tolerance was determined by detecting the 2,3,5-triphenyl tetrazolium chloride (TTC) reductants in roots and soil water content (SWC). The critical value for drought tolerance was SWC 6% while for the control plants the critical SWC was 8%; a moderate level of SWC is 13% and the highest SWC for plant endurance was 18%. The method proved to be reliable and sensitive in the evaluation of drought tolerance for forest trees.  相似文献   

14.
The Great Xing’an Mountains boreal forests were focused on in the northeastern China.The simulated future climate scenarios of IPCC SRES A2a and B2a for both the baseline period of 1961-1990 and the future scenario periods were downscaled by the Delta Method and the Weather Generator to produce daily weather data.After the verification with local weather and fire data,the Canadian Forest Fire Weather Index System was used to assess the forest fire weather situation under climate change in the study region.An increasing trend of fire weather severity was found over the 21st century in the study region under the both future climate change scenarios,compared to the 1961-1990 baseline period.The annual mean/maximum fire weather index was predicted to rise continuously during 2010-2099,and by the end of the 21st century it is predicted to rise by 22%-52% across much of China’s boreal forest.The significant increases were predicted in the spring from of April to June and in the summer from July to August.In the summer,the fire weather index was predicted to be higher than the current index by as much as 148% by the end of the 21st century.Under the scenarios of SRES A2a and B2a,both the chance of extremely high fire danger occurrence and the number of days of extremely high fire danger occurrence was predicted to increase in the study region.It is anticipated that the number of extremely high fire danger days would increase from 44 days in 1980s to 53-75 days by the end of the 21st century.  相似文献   

15.
The utilization and changes of forest resources were studied in the Lishuihe Forest Bureau. Based on remote sensing images in 1985 and 1999, changes of major forest resources were analyzed by statistical and overlap method and classified quantitatively. The results showed that in recent 15 years, logging spots and man-made young forest changed violently, which was due to human activities. Different forest management manners and harvesting intensity played an important role in forest resources change. Dongsheng and Xilinhe tree farms were typical cases of different forest status and management for the Bureau, where forest succession was intervened by either human or natural disturbance. Dongsheng Tree Farm underwent a lighth arvest intensity and maintained a unit stock volume of 536.27 m^3. hm^-2, as much as that of broadleaf/Korean pine forest of Changbai Mountain Natural Reserve; Xilinhe Tree Farm underwent an intense harvest and was composed of secondary forests,where mature forests just had a small percentage and the unit stock volume was low. The study was useful to guide future forest management. What‘s more, problems found in the research were also analyzed and reasonable advice was given to the local forest management.  相似文献   

16.
Windthrow problem is a difficult task for the forest managers in the Romanian Carpathians and especially in Iezer Mountains. The last windthrow, in July 2005, affected about 370 ha within the study area and left unprotected large slopes with important declivities (20-30°). In our study, we try to propose a tool for forest management, in order to control and minimize the negative effect of wind upon the mountain forest ecosystem. The digital data input derived from forestry data (forest stand typology, age, canopy coverage index, forest productivity class) and from the forest biotope features (soil and topography parameters). The main goal was to find a more objective way for digital layer reclassification in order to obtain the windthrow areas susceptibility map for the Iezer Mountains. Each digital layer has its own weight within the analysis and one of them was difficult to be modeled (the wind features). A statistical approach was developed on the basis of local phenomena and the windthrow features in the Romanian Carpathians. This allowed us to obtain the reclassification conditions for each digital layer. Forest canopy typology and soil features (mainly its volume) were considered as the key factors for the windthrow occurrence analysis. The final windthrow susceptibility map was validated with the help of the statistic occurrence of windthrow areas within each susceptibility class and after a field check of the sites. The result was encouraging, because 92.5% of the windthrow areas fall into the highest windthrow susceptibility class.  相似文献   

17.
A difficult problem in forestry is tree inventory.In this study, a GoProHero attached to a small unmanned aerial vehicle was used to capture images of a small area covered by pinus pinea trees. Then, a digital surface model was generated with image matching. The elevation model representing the terrain surface, a ‘digital terrain model’,was extracted from the digital surface model using morphological filtering. Individual trees were extracted by analyzing elevation flow on the digital elevation model because the elevation reached the highest value on the tree peaks compared to the neighborhood elevation pixels. The quality of the results was assessed by comparison with reference data for correctness of the estimated number of trees. The tree heights were calculated and evaluated with ground truth dataset. The results showed 80% correctness and 90% completeness.  相似文献   

18.
Predicting upper stem diameters and individual tree volumes is important for product quantification and can provide important information for the sustainable management of forests of important commercial tree species( Shorea robusta) in Nepal. The aim of this study was to develop a taper equation for S. robusta. Fifty-four trees were selected and felled in the southern low land of Nepal. A mixed effect modelling approach was used to evaluate 17 different taper functions. ‘Leave-one-out cross-val...  相似文献   

19.
By the contingent value method, we studied the non-use value of wetland ecosystem service of Hongxing National Nature Reserve(HNNR) in Heilongjiang Province, northeast China. The proportion of respondents willing to pay(WTP) for protection of HNNR was 63 %.The WTP ratio was affected by geographical area, contact nature, personal preferences, and familiar degree of the respondents. The WTP value was affected by age, education level and career of the respondents. The mainly reasons for people rejecting to pay for protecting HNNR were‘‘I am not familiar to HNNR' and ‘‘I had no capacity for additional spending because of low income'. Weighted average individual WTP value was CNY 59.26 Yuan ind.~(-1) year~(-1) for all the respondents with WTP. The total non-use ecosystem service value of HNNR was CNY 1430 million Yuan in 2013. The heritage value was highest followed by existence value and option value. From the high ecosystem service value in HNNR, it is very important to construct nature reserve for protecting natural ecosystems and human sustainable use of natural resources.  相似文献   

20.
Daxing'anling is a key region for forest fire prevention in China.Assessing changes in fire risk in the future under multiple climatic scenarios will contribute to our understanding of the influences of climate change for the region and provide a reference for applying adaptive measures for fire management.This study analyzed the changes in fire weather indices and the fire season under four climate scenarios(RCP2.6,RCP4.5,RCP6.0,RCP8.5)for 2021–2050 using data from five global climate models together with observation data.The results showed that the analog data could project the average state of the climate for a given period but were not effective for simulating extreme weather conditions.Compared with the baseline period(1971–2000),the period 2021–2050 was predicted to have an increase in average temperature of 2.02–2.65 °C and in annual precipitation 25.4–40.3 mm,while the fire weather index(FWI) was predicted to increase by6.2–11.2% and seasonal severity rating(SSR) by5.5–17.2%.The DMC(Duff moisture code),ISI(initial spread index),BUI(build-up index),FWI and SSR were predicted to increase significantly under scenarios RCP4.5,RCP6.0,and RCP8.5.Furthermore,days with high or higher fire danger rating were predicted to be prolonged by 3–6 days,with the change in the southern region being greater under scenarios RCP4.5,RCP6.0,and RCP8.5.  相似文献   

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