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1

The Reference Genome of the Halophytic Plant Eutrema salsugineum.  

PubMed

Halophytes are plants that can naturally tolerate high concentrations of salt in the soil, and their tolerance to salt stress may occur through various evolutionary and molecular mechanisms. Eutrema salsugineum is a halophytic species in the Brassicaceae that can naturally tolerate multiple types of abiotic stresses that typically limit crop productivity, including extreme salinity and cold. It has been widely used as a laboratorial model for stress biology research in plants. Here, we present the reference genome sequence (241?Mb) of E. salsugineum at 8× coverage sequenced using the traditional Sanger sequencing-based approach with comparison to its close relative Arabidopsis thaliana. The E. salsugineum genome contains 26,531 protein-coding genes and 51.4% of its genome is composed of repetitive sequences that mostly reside in pericentromeric regions. Comparative analyses of the genome structures, protein-coding genes, microRNAs, stress-related pathways, and estimated translation efficiency of proteins between E. salsugineum and A. thaliana suggest that halophyte adaptation to environmental stresses may occur via a global network adjustment of multiple regulatory mechanisms. The E. salsugineum genome provides a resource to identify naturally occurring genetic alterations contributing to the adaptation of halophytic plants to salinity and that might be bioengineered in related crop species. PMID:23518688

Yang, Ruolin; Jarvis, David E; Chen, Hao; Beilstein, Mark A; Grimwood, Jane; Jenkins, Jerry; Shu, Shengqiang; Prochnik, Simon; Xin, Mingming; Ma, Chuang; Schmutz, Jeremy; Wing, Rod A; Mitchell-Olds, Thomas; Schumaker, Karen S; Wang, Xiangfeng

2013-01-01

2

Threat of heavy metal pollution in halophytic and mangrove plants of Tamil Nadu, India.  

PubMed

Mangrove and halophytic plants occur along the coastal areas of Tamil Nadu, south India and these plants have been used in traditional medicine for centuries. Heavy metals are known to pose a potential threat to terrestrial and aquatic biota. However, little is known on the toxic levels of heavy metals found in mangrove and halophytic plants that are used in traditional medicine in India. To understand heavy metal toxicity, we investigated the bioconcentration factors (BCF) of heavy metals in leaves collected from eight mangroves and five halophytes in the protected Pichavaram mangrove forest reserve in Tamil Nadu State, south India. Data presented in this paper describe the impact of essential (Cu, Fe, Mg, Mn and Zn) and non-essential/environmentally toxic trace metals (Hg, Pb and Sn) in mangrove and halophytic medicinal plants. The concentrations of Pb among 13 plant species were higher than the normal range of contamination reported for plants. The average concentration of Hg in the halophytic plants (0.43+/-0.37 microg/g) was seven times higher than mangrove plants (0.06+/-0.03 microg/g) and it indicated pollutants from industrial sources affecting halophytes more than mangroves. PMID:18086510

Agoramoorthy, Govindasamy; Chen, Fu-An; Hsu, Minna J

2008-09-01

3

The use of a halophytic plant species and organic amendments for the remediation of a trace elements-contaminated soil under semi-arid conditions.  

PubMed

The halophytic shrub Atriplex halimus L. was used in a field phytoremediation experiment in a semi-arid area highly contaminated by trace elements (As, Cd, Cu, Mn, Pb and Zn) within the Sierra Minera of La Unión-Cartagena (SE Spain). The effects of compost and pig slurry on soil conditions and plant growth were determined. The amendments (particularly compost) only slightly affected trace element concentrations in soil pore water or their availability to the plants, increased soil nutrient and organic matter levels and favoured the development of a sustainable soil microbial biomass (effects that were enhanced by the presence of A. halimus) as well as, especially for slurry, increasing A. halimus biomass and ground cover. With regard to the minimisation of trace elements concentrations in the above-ground plant parts, the effectiveness of both amendments was greatest 12-16 months after their incorporation. The findings demonstrate the potential of A. halimus, particularly in combination with an organic amendment, for the challenging task of the phytostabilisation of contaminated soils in (semi-)arid areas and suggest the need for an ecotoxicological evaluation of the remediated soils. However, the ability of A. halimus to accumulate Zn and Cd in the shoot may limit its use to moderately-contaminated sites. PMID:22595543

Clemente, Rafael; Walker, David J; Pardo, Tania; Martínez-Fernández, Domingo; Bernal, M Pilar

2012-07-15

4

Accumulation and distribution of Zn in the shoots and reproductive structures of the halophyte plant species Kosteletzkya virginica as a function of salinity.  

PubMed

Kosteletzkya virginica is a wetland halophyte that is a good candidate for rehabilitation of degraded salt marshes and production of oil as biodiesel. Salt marshes are frequently contaminated by heavy metals. The distribution of Zn in vegetative and reproductive organs of adult plants, and the NaCl influence on this distribution remain unknown and were thus explored in the present study. Plants were cultivated in a nutrient film technique system, from seedling stage until seed maturation in a control, Zn (100 ?M), NaCl (50 mM) or Zn + NaCl medium. Photosynthesis, ion nutrition, malondialdehyde and non-protein thiol concentrations were quantified. Zinc distribution in reproductive organs was estimated by a laser ablation-inductively coupled plasma-mass spectrometry procedure (LA-ICP-MS). Adult plants accumulated up to 2 mg g(-1) DW Zn in the shoots. Zinc reduced plant growth, inhibited photosynthesis and reduced seed yield. Zinc accumulation in the seeds was only two times higher in Zn-treated plants than in controls. Exogenous NaCl neutralized the damaging action of Zn and modified the Zn distribution through a preferential accumulation of toxic ions in older leaves. Zinc was present in seed testa, endosperm and, to a lower extent, in embryo. Additional NaCl induced a chalazal retention of Zn during seed maturation and reduced final Zn seed content. It is concluded that NaCl 50 mM had a positive impact on the response of K. virginica to Zn toxicity and acts through a modification in Zn distribution rather than a decrease in Zn absorption. PMID:23728368

Han, Ruiming; Quinet, Muriel; André, Emilie; van Elteren, Johannes Teun; Destrebecq, Florence; Vogel-Mikuš, Katarina; Cui, Guangling; Debeljak, Marta; Lefèvre, Isabelle; Lutts, Stanley

2013-09-01

5

Flooding tolerance in halophytes.  

PubMed

Flooding is a common environmental variable with salinity. Submerged organs can suffer from O(2) deprivation and the resulting energy deficits can compromise ion transport processes essential for salinity tolerance. Tolerance of soil waterlogging in halophytes, as in glycophytes, is often associated with the production of adventitious roots containing aerenchyma, and the resultant internal O(2) supply. For some species, shallow rooting in aerobic upper soil layers appears to be the key to survival on frequently flooded soils, although little is known of the anoxia tolerance in halophytes. Halophytic species that inhabit waterlogged substrates are able to regulate their shoot ion concentrations in spite of the hypoxic (or anoxic) medium in which they are rooted, this being in stark contrast with most other plants which suffer when salinity and waterlogging occur in combination. Very few studies have addressed the consequences of submergence of the shoots by saline water; these have, however, demonstrated tolerance of temporary submergence in some halophytes. PMID:18482227

Colmer, Timothy D; Flowers, Timothy J

2008-01-01

6

Radical scavenging, antioxidant and antimicrobial activities of halophytic species Laetitia Meot-Durosa*  

E-print Network

Radical scavenging, antioxidant and antimicrobial activities of halophytic species Laetitia Meot maritimum, Cakile maritima, Crithmum maritimum, antimicrobial, antioxidant, phenol content Abbreviations; BCC: Brittany Culture Collection; GAE: Gallic Acid Equivalents; TAC: Total Antioxidant Capacity. hal

Paris-Sud XI, Université de

7

Selection of a halophytic plant for assessing the phytotoxicity of dredged seaport sediment stored on land.  

PubMed

The filling of dry quarries in coastal areas with sediments dredged in seaports represents a potentially interesting method of recycling of these materials. However, this recycling requires the prior carrying out of an Environmental Risk Assessment of the scenario concerned. For this, the question arose as to the type of plants capable of developing on the surface of such a deposit and the method to implement for assessing the possible phytotoxicity of dredged sediments. To answer this question, we chose to work with halophytic plants to be free from the salt-related effect and to assess only the effect related to the toxic compounds present. Based on the objectives set, these works led to the use of common plants of the French coast, with direct seeding, and with pollution-sensitive plants. Three species of angiosperms, Armeria maritima, Anthemis maritima and Plantago coronopus, were finally tested. As a result of this work, Armeria maritima was retained as the most suitable plant for testing the possible phytotoxic effect of dredged marine sediments stored on land. The results obtained with this plant are as follows: germination of 40 % of the seeds in 31 days, produced biomass of 493 mg FW in 6 months and a capacity to bioaccumulate metal pollutants in roots with 350 and 720 mg/kg DW for Zn and Cu, respectively. PMID:23955497

Bedell, J-P; Ferro, Y; Bazin, C; Perrodin, Y

2014-01-01

8

The effects of heavy metals on germination and seedling characteristics in two halophyte species in Mediterranean marshes.  

PubMed

The influence of different concentrations (10-2000 ?M) of heavy metals (Cu, Mn, Ni, Zn) was analysed in Atriplex halimus and Salicornia ramosissima germination pattern and seedling size. They are two halophyte species that grow in the Estuary of Huelva (Southwest Iberian Peninsula, Spain), one of the most heavy metal-polluted environments in the world. All of the metals tested affected the final germination percentage in A. halimus and only Ni reduced germination in S. ramosissima. The germination rate was unaffected in both species. The study of seedling development shows that S. ramosissima, an intertidal annual species, has a higher tolerance of metals than A. halimus, a bush that inhabits the upper part of the marshes. Taking into account the metal concentrations in the estuary and the effects of these on the seedling development of the species analysed, we conclude that metals might limit plant colonisation in some parts of the marshes. PMID:23465623

Márquez-García, B; Márquez, C; Sanjosé, I; Nieva, F J J; Rodríguez-Rubio, P; Muñoz-Rodríguez, A F

2013-05-15

9

Differential Activity of Plasma and Vacuolar Membrane Transporters Contributes to Genotypic Differences in Salinity Tolerance in a Halophyte Species, Chenopodium quinoa  

PubMed Central

Halophytes species can be used as a highly convenient model system to reveal key ionic and molecular mechanisms that confer salinity tolerance in plants. Earlier, we reported that quinoa (Chenopodium quinoa Willd.), a facultative C3 halophyte species, can efficiently control the activity of slow (SV) and fast (FV) tonoplast channels to match specific growth conditions by ensuring that most of accumulated Na+ is safely locked in the vacuole (Bonales-Alatorre et al. (2013) Plant Physiology). This work extends these finding by comparing the properties of tonoplast FV and SV channels in two quinoa genotypes contrasting in their salinity tolerance. The work is complemented by studies of the kinetics of net ion fluxes across the plasma membrane of quinoa leaf mesophyll tissue. Our results suggest that multiple mechanisms contribute towards genotypic differences in salinity tolerance in quinoa. These include: (i) a higher rate of Na+ exclusion from leaf mesophyll; (ii) maintenance of low cytosolic Na+ levels; (iii) better K+ retention in the leaf mesophyll; (iv) a high rate of H+ pumping, which increases the ability of mesophyll cells to restore their membrane potential; and (v) the ability to reduce the activity of SV and FV channels under saline conditions. These mechanisms appear to be highly orchestrated, thus enabling the remarkable overall salinity tolerance of quinoa species. PMID:23629664

Bonales-Alatorre, Edgar; Pottosin, Igor; Shabala, Lana; Chen, Zhong-Hua; Zeng, Fanrong; Jacobsen, Sven-Erik; Shabala, Sergey

2013-01-01

10

A review on Cressa cretica Linn.: A halophytic plant  

PubMed Central

Herbal medicine is used by up to 80% of the population in developing countries. Cressa cretica L. is a popular holophytic plant and is used in folklore medicine for ailments including diabetes, ulcers, asthma, anthelmintic, stomachic, tonic and aphrodisiac purposes, enriches the blood, and is useful in constipation, leprosy, and urinary discharges. The plant is traditionally used in Bahrain as expectorant and antibilious agent. Scientific evidence suggests its versatile biological functions such as its antibacterial, antifungal, antitussive, anticancer with some other plants, anti-inflammatory, and improving testicular function in rats. In this article, a comprehensive account of the morphology, phytochemical constituents, ethnobotany, and biological activities are included in view of the recent findings of importance on the plant, C. cretica. PMID:22228956

Priyashree, S.; Jha, S.; Pattanayak, S. P.

2010-01-01

11

Effects of plant growth regulators and l -glutamic acid on shoot organogenesis in the halophyte Leymus chinensis (Trin.)  

Microsoft Academic Search

The halophyte Leymus chinensis (Trin.) is a perennial rhizome grass (tribe Gramineae) that is widely distributed in China, Mongolia and Siberia, where it\\u000a is produced as a forage product. In this report, we establish a highly reproducible plant regeneration system through somatic\\u000a embryogenesis. Two explants, mature seeds and leaf base segments were used; these parts displayed different responses to combinations

Yan-Lin Sun; Soon-Kwan Hong

2010-01-01

12

Environmental and Developmental Regulation of the Wound-Induced Cell Wall Protein WI12 in the Halophyte Ice Plant1  

Microsoft Academic Search

A wounded gene WI12 was used as a marker to examine the interaction between biotic stress (wounding) and abiotic stress (high salt) in the facultative halophyte ice plant (Mesembryanthemum crystallinum). The deduced WI12 amino acid sequence has 68% similarity to WUN1, a known potato (Solanum tuberosum) wound-induced protein. Wounding, methyl jasmonate, and pathogen infection induced local WI12 expression. Upon wounding,

Shyi-Kae Yen; Mei-Chu Chung; Pei-Chung Chen; Hungchen E. Yen

2001-01-01

13

Restoring assemblages of salt marsh halophytes in the presence of a rapidly colonizing dominant species  

Microsoft Academic Search

Establishing species-rich plant communities is a common goal of habitat restoration efforts, but not all species within a\\u000a target assemblage have the same capacity for recruitment and survival in created habitats. We investigated the development\\u000a of a tidal salt marsh plant community in the presence of a rapidly colonizing dominant species, Salicornia virginica, in a newly created habitat in Mugu

Anna R. Armitage; Katharyn E. Boyer; Richard R. Vance; Richard F. Ambrose

2006-01-01

14

Potential use of halophytes to remediate saline soils.  

PubMed

Salinity is one of the rising problems causing tremendous yield losses in many regions of the world especially in arid and semiarid regions. To maximize crop productivity, these areas should be brought under utilization where there are options for removing salinity or using the salt-tolerant crops. Use of salt-tolerant crops does not remove the salt and hence halophytes that have capacity to accumulate and exclude the salt can be an effective way. Methods for salt removal include agronomic practices or phytoremediation. The first is cost- and labor-intensive and needs some developmental strategies for implication; on the contrary, the phytoremediation by halophyte is more suitable as it can be executed very easily without those problems. Several halophyte species including grasses, shrubs, and trees can remove the salt from different kinds of salt-affected problematic soils through salt excluding, excreting, or accumulating by their morphological, anatomical, physiological adaptation in their organelle level and cellular level. Exploiting halophytes for reducing salinity can be good sources for meeting the basic needs of people in salt-affected areas as well. This review focuses on the special adaptive features of halophytic plants under saline condition and the possible ways to utilize these plants to remediate salinity. PMID:25110683

Hasanuzzaman, Mirza; Nahar, Kamrun; Alam, Md Mahabub; Bhowmik, Prasanta C; Hossain, Md Amzad; Rahman, Motior M; Prasad, Majeti Narasimha Vara; Ozturk, Munir; Fujita, Masayuki

2014-01-01

15

Halophytic plants as a component of a bioregenerative life support system for recycling of NaCl contained in human liquid waste.  

NASA Astrophysics Data System (ADS)

Currently, the closure of matter turnover is one of the urgent problems of bioregenerative life support system (BLSS) designing. The important aspect of the problem is involving of substances contained in liquid and solid exometabolites of humans inhabiting BLSS into intrasystem matter turnover. Recycling of Na+ and Cl- contained in human liquid exometabolites, i.e. urine is acknowledged to be among the main tasks of the matter turnover in BLSS. The ions excreted with urine may be returned to human organism with food. A way to allow this is including edible halophytic plants into the phototrophic compartment of BLSS. Halophytes are defined as plants which can grow on saline soils and produce high biomass under these conditions. Some halophytes can take up high quantities of Na+ and Cl- and accumulate the ions in the shoots or extrude them to leaf surface by means of salt glands. To allow Na+ and Cl- recycling through halophyte utilization, the following principal steps should be accomplished: (i) mineralization of the exometabolites by physicochemical methods; (ii) oxidation of ammonia formed during the exometabolite mineralization to nitrate by nitrifying bacteria, (iii) growing the halophyte on the nutrient solution prepared on the basis of the mineralized exometabolites, (iv) introducing the halophyte green biomass into human food. The present work is devoted to the following problems: (i) selection of a salt-accumulating/extruding halophytic plant suitable for Na+ and Cl- recycling in BLSS and (ii) parameter evaluation of a plant conveyor containing the halophytic plants at various ages. Halophytic plants selected for BLSS should meet the following criteria: (i) ability to grow under 24-hour-illumination, (ii) high productivity, (iii) ability to accumulate Na+ and Cl- in high quantities in shoots or to excrete salts to leaf surface, (iv) edibility, and (v) high nutritive value of the biomass. Relying on these criteria, salt-accumulating halophyte Salicornia europaea was selected from seven halophytic plant candidates, preliminary chosen from observations in their natural habitats, from our previous investigations and literature data. Characterization of the plant performance was obtained in the experiments on plants grown in water culture in a cultivation chamber under controlled conditions. A model nutrient solution simulating mineralized urine was used for halophyte growing. Under the experimental conditions, S.europaea exhibited high productivity and accumulated Na+ and Cl- in the shoots in high quantities. It has been shown that above-ground organs of S.europaea exhibit high nutritive value, the proteins are enriched with the essential amino acids and displayed high abundance of leucine, aspartic and glutamic acids. The results demonstrate that it is feasible to put into practice permanent Na+ and Cl- recycling in BLSS by a various-aged S.europaea conveyor. Relying on data on distribution of Na+ and Cl- between the plant and growth medium, parameters of the conveyor for permanent ion turnover in the system humans - exometabolites - nutrient solution - S.europaea - humans have been evaluated.

Balnokin, Yurii; Balnokin, Yurii; Myasoedov, Nikolay; Popova, Larissa; Tikhomirov, Alexander A.; Ushakova, Sofya; Tikhomirova, Natalia; Lasseur, Christophe; Gros, Jean-Bernard

16

Potential uses of TerraSAR-X for mapping herbaceous halophytes over salt marsh and tidal flats  

NASA Astrophysics Data System (ADS)

This study presents a method and application results of mapping different halophytes over tidal flats and salt marshes using high resolution space-borne X-band synthetic aperture radar (SAR) that has been rarely used for salt marsh mapping. Halophytes in a salt marshes are sensitive to sea-level changes, sedimentation, and anthropogenic modifications. The alteration of the demarcations among halophyte species is an indicator of sea level and environmental changes within a salt marsh. The boundary of an herbaceous halophyte patch is, however, difficult to determine using remotely sensed data because of its sparseness. We examined the ecological status of the halophytes and their distribution changes using TerraSAR-X and optical data. We also determined the optimum season for halophyte mapping. An annual plant, Suaeda japonica (S. japonica), and a typical perennial salt marsh grass, Phragmites australis (P. australis), were selected for halophyte analysis. S. japonica is particularly sensitive to sea level fluctuation. Seasonal variation for the annual plant was more significant (1.47 dB standard deviation) than that for the perennial grass, with a pattern of lower backscattering in winter and a peak in the summer. The border between S. japonica and P. australis was successfully determined based on the distinctive X-band radar backscattering features. Winter is the best season to distinguish between the two different species, while summer is ideal for analyzing the distribution changes of annual plants in salt marshes. For a single polarization, we recommend using HH polarization, because it produces maximum backscattering on tidal flats and salt marshes. Our results show that high resolution SAR, such as TerraSAR-X and Cosmo-SkyMed, is an effective tool for mapping halophyte species in tidal flats and monitoring their seasonal variations.

Lee, Yoon-Kyung; Park, Jeong-Won; Choi, Jong-Kuk; Oh, Yisok; Won, Joong-Sun

2012-12-01

17

Maritime Halophyte Species from Southern Portugal as Sources of Bioactive Molecules  

PubMed Central

Extracts of five halophytes from southern Portugal (Arthrocnemum macrostachyum, Mesembryanthemum edule, Juncus acutus, Plantago coronopus and Halimione portulacoides), were studied for antioxidant, anti-inflammatory and in vitro antitumor properties. The most active extracts towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical were the methanol extracts of M. edule (IC50 = 0.1 mg/mL) and J. acutus (IC50 = 0.4 mg/mL), and the ether extracts of J. acutus (IC50 = 0.2 mg/mL) and A. macrostachyum (IC50 = 0.3 mg/mL). The highest radical scavenging activity (RSA) against the 2,2?-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical was obtained in the ether extract of J. acutus (IC50 = 0.4 mg/mL) and H. portulacoides (IC50 = 0.9 mg/mL). The maximum total phenolic content (TPC) was found in the methanol extract of M. edule (147 mg gallic acid equivalents (GAE)/g) and in the ether extract of J. acutus (94 mg GAE/g). Significant decreases in nitric oxide (NO) production were observed after incubation of macrophages with lipopolysaccharide (LPS) and the chloroform extract of H. portulacoides (IC50 = 109 µg/mL) and the hexane extract of P. coronopus (IC50 = 98.0 µg/mL). High in vitro cytotoxic activity and selectivity was obtained with the ether extract of J. acutus. Juncunol was identified as the active compound and for the first time was shown to display selective in vitro cytotoxicity towards various human cancer cells. PMID:24727393

Rodrigues, Maria Joao; Gangadhar, Katkam N.; Vizetto-Duarte, Catarina; Wubshet, Sileshi G.; Nyberg, Nils T.; Barreira, Luisa; Varela, Joao; Custodio, Luisa

2014-01-01

18

Maritime halophyte species from southern Portugal as sources of bioactive molecules.  

PubMed

Extracts of five halophytes from southern Portugal (Arthrocnemum macrostachyum, Mesembryanthemum edule, Juncus acutus, Plantago coronopus and Halimione portulacoides), were studied for antioxidant, anti-inflammatory and in vitro antitumor properties. The most active extracts towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical were the methanol extracts of M. edule (IC?? = 0.1 mg/mL) and J. acutus (IC?? = 0.4 mg/mL), and the ether extracts of J. acutus (IC?? = 0.2 mg/mL) and A. macrostachyum (IC?? = 0.3 mg/mL). The highest radical scavenging activity (RSA) against the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical was obtained in the ether extract of J. acutus (IC?? = 0.4 mg/mL) and H. portulacoides (IC?? = 0.9 mg/mL). The maximum total phenolic content (TPC) was found in the methanol extract of M. edule (147 mg gallic acid equivalents (GAE)/g) and in the ether extract of J. acutus (94 mg GAE/g). Significant decreases in nitric oxide (NO) production were observed after incubation of macrophages with lipopolysaccharide (LPS) and the chloroform extract of H. portulacoides (IC?? = 109 µg/mL) and the hexane extract of P. coronopus (IC?? = 98.0 µg/mL). High in vitro cytotoxic activity and selectivity was obtained with the ether extract of J. acutus. Juncunol was identified as the active compound and for the first time was shown to display selective in vitro cytotoxicity towards various human cancer cells. PMID:24727393

Rodrigues, Maria João; Gangadhar, Katkam N; Vizetto-Duarte, Catarina; Wubshet, Sileshi G; Nyberg, Nils T; Barreira, Luísa; Varela, João; Custódio, Luísa

2014-04-01

19

[Response characteristics of the field-measured spectrum for the four gerneral types of halophyte and species recognition in the northern slope area of Tianshan Mountain in Xinjiang].  

PubMed

Based on the field-measured Vis-NIR reflectance of four common types of halophyte (Achnatherum splendens(Trin.) Nevski, Sophora alopecuroides L., Camphorosma monspeliaca L. subsp. lessingii(L.)Aellen, Alhagi sparsifolia shap) within given spots in the Northern Slope Area of Tianshan Mountain in Xinjiang, the spectral response characteristics and species recognition of these types of halophyte were analyzed. The results showed that (Alhagi sparsifolia shap) had higher chlorophyll and carotenoid by CARI and SIPI index. (Sophora alopecuroides L. was at a vigorously growing state and had a higher NDVI compared with the other three types of halophyte because of its greater canopy density. But its CARI and SIPI values were lower due to the influence of its flowers. (Sophora alopecuroides L.) and (Camphorosma monspeliaca L. subsp. lessingii(L.)) had stable REPs and BEPs, but REPs and BEPs of (Achnatherum splendens(Trin.)Nevski, Aellen, Alhagi sparsifolia shap) whose spectra red shift and spectra blue shift occurred concurrently obviously changed. There was little difference in spectral curves among the four types of halophyte, so the spectrum mixing phenomenon was severe. (Camphorosma monspeliaca L. subsp. lessingii (L.)Aellen) and (Alhagi sparsifolia shap) could not be separated exactly in a usual R/NIR feature space in remote sensing. Using the stepwise discriminant analysis, five indices were selected to establish the discriminant model, and the model accuracy was discussed using the validated sample group. The total accuracy of the discriminant model was above 92% and (Achnatherum splendens(Trin.)Nevski) and (Camphorosma monspeliaca L. subsp. lessingii(L.)Aellen) could be respectively recognized 100% correctly. PMID:22295790

Zhang, Fang; Xiong, Hei-gang; Nurbay, Abdusalih; Luan, Fu-ming

2011-12-01

20

The roots of the halophyte Salicornia brachiata are a source of new halotolerant diazotrophic bacteria with plant growth-promoting potential  

Microsoft Academic Search

Soil salinity is the major cause limiting plant productivity worldwide. Nitrogen-fixing bacteria were enriched and characterised\\u000a from roots of Salicornia brachiata, an extreme halophyte which has substantial economic value as a bioresource of diverse and valuable products. Nitrogen-free\\u000a semisolid NFb medium with malate as carbon source and up to 4% NaCl were used for enrichment and isolation of diazotrophic\\u000a bacteria.

Bhavanath Jha; Iti Gontia; Anton Hartmann

21

Environmental and developmental regulation of the wound-induced cell wall protein WI12 in the halophyte ice plant.  

PubMed

A wounded gene WI12 was used as a marker to examine the interaction between biotic stress (wounding) and abiotic stress (high salt) in the facultative halophyte ice plant (Mesembryanthemum crystallinum). The deduced WI12 amino acid sequence has 68% similarity to WUN1, a known potato (Solanum tuberosum) wound-induced protein. Wounding, methyl jasmonate, and pathogen infection induced local WI12 expression. Upon wounding, the expression of WI12 reached a maximum level after 3 h in 4-week-old juvenile leaves, whereas the maximum expression was after 24 h in 8-week-old adult leaves. The temporal expression of WI12 in salt-stressed juvenile leaves was similar to that of adult leaves. The result suggests that a salt-induced switch from C3 to Crassulacean acid metabolism has a great influence on the ice plant's response to wounding. The expression of WI12 and the accumulation of WI12 protein were constitutively found in phloem and in wounded mesophyll cells. At the reproductive stage, WI12 was constitutively found in petals and styles, and developmentally regulated in the placenta and developing seeds. The histochemical analysis showed that the appearance of WI12 is controlled by both environmental and developmental factors. Immunogold labeling showed WI12 preferentially accumulates in the cell wall, suggesting its role in the reinforcement of cell wall composition after wounding and during plant development. PMID:11598226

Yen, S K; Chung, M C; Chen, P C; Yen, H E

2001-10-01

22

Salinity effects on germination, growth, and seed production of the halophyte Cakile maritima  

Microsoft Academic Search

Cakile maritima (Brassicaceae) is a halophyte that thrives on dunes along the Tunisian seashore. Besides its ecological interest for soil fixation, this plant produces seeds rich in lipids (40% on dry weight basis), making it a potential source of oil for industrial use. The purpose of the present work was to study the salt tolerance of this species at germination,

Ahmed Debez; Karim Ben Hamed; Claude Grignon; Chedly Abdelly

2004-01-01

23

Antioxidative response mechanisms in halophytes: their role in stress defence.  

PubMed

Normal growth and development of plants is greatly dependent on the capacity to overcome environmental stresses. Environmental stress conditions like high salinity, drought, high incident light and low or high temperature cause major crop losses worldwide. A common denominator in all these adverse conditions is the production of reactive oxygen species (ROS) within different cellular compartments of the plant cell. Plants have developed robust mechanisms including enzymatic or nonenzymatic scavenging pathways to counter the deleterious effects of ROS production. There are a number of general reviews on oxidative stress in plants and few on the role of ROS scavengers during stress conditions. Here we review the regulation of antioxidant enzymes during salt stress in halophytes, especially mangroves. We conclude that (i) antioxidant enzymes protect halophytes from deleterious ROS production during salt stress, and (ii) genetic information from mangroves and other halophytes would be helpful in defining the roles of individual isoforms. This information would be critical in using the appropriate genes for oxidative stress defence for genetic engineering of enhanced stress tolerance in crop systems. PMID:17406103

Jithesh, M N; Prashanth, S R; Sivaprakash, K R; Parida, Ajay K

2006-12-01

24

RESTORING ASSEMBLAGES OF SALT MARSH HALOPHYTES IN THE PRESENCE OF A RAPIDLY COLONIZING DOMINANT SPECIES  

E-print Network

, Distichlis spicata, Jaumea carnosa, and Frankenia salina in single- and mixed-species stands, where each. salina (35%), and D. spicata (12%). Total percent cover was about 30% lower than in a reference site

Boyer, Katharyn

25

ROS homeostasis in halophytes in the context of salinity stress tolerance.  

PubMed

Halophytes are defined as plants that are adapted to live in soils containing high concentrations of salt and benefiting from it, and thus represent an ideal model to understand complex physiological and genetic mechanisms of salinity stress tolerance. It is also known that oxidative stress signalling and reactive oxygen species (ROS) detoxification are both essential components of salinity stress tolerance mechanisms. This paper comprehensively reviews the differences in ROS homeostasis between halophytes and glycophytes in an attempt to answer the questions of whether stress-induced ROS production is similar between halophytes and glycophytes; is the superior salinity tolerance in halophytes attributed to higher antioxidant activity; and is there something special about the specific 'pool' of enzymatic and non-enzymatic antioxidants in halophytes. We argue that truly salt-tolerant species possessing efficient mechanisms for Na(+) exclusion from the cytosol may not require a high level of antioxidant activity, as they simply do not allow excessive ROS production in the first instance. We also suggest that H2O2 'signatures' may operate in plant signalling networks, in addition to well-known cytosolic calcium 'signatures'. According to the suggested concept, the intrinsically higher superoxide dismutase (SOD) levels in halophytes are required for rapid induction of the H2O2 'signature', and to trigger a cascade of adaptive responses (both genetic and physiological), while the role of other enzymatic antioxidants may be in decreasing the basal levels of H2O2, once the signalling has been processed. Finally, we emphasize the importance of non-enzymatic antioxidants as the only effective means to prevent detrimental effects of hydroxyl radicals on cellular structures. PMID:24368505

Bose, Jayakumar; Rodrigo-Moreno, Ana; Shabala, Sergey

2014-03-01

26

Collection and composition of xylem sap and root structure in two halophytic species  

Microsoft Academic Search

Leptochloa fusca (L.) Kunth and Atriplex hortensis (L.) were grown on quartz sand or in liquid culture in the presence of varied concentrations of NaCl. Xylem sap was collected as (a) root pressure exudate, in L. fusca even at 100 mM NaCl, (b) by applying pressure to excised roots of L. fusca and (c) from leaves of the whole plant

W. Dieter Jeschke; Sabine Klagges I; A. Saeed Bhatti

1995-01-01

27

Halophytes Energy Feedstocks: Back to Our Roots  

NASA Technical Reports Server (NTRS)

Of the Earth s landmass, approx.43% is arid or semi-arid, and 97% of the Earth s water is seawater. Halophytes are salt-tolerant plants (micro and macro) that can prosper in seawater or brackish waters and are common feedstocks for fuel and food (fuel-food feedstocks) in depressed countries. Two types, broadly classed as coastal and desert, can be found in marshes, coastal planes, inland lakes, and deserts. Major arid or semi-arid halophyte agriculture problems include pumping and draining the required high volumes of irrigation water from sea or ocean sources. Also, not all arid or semi-arid lands are suitable for crops. Benefits of halophyte agriculture include freeing up arable land and freshwater resources, cleansing the environment, decontaminating soils, desalinating brackish waters, and carbon sequestration. Sea and ocean halophyte agriculture problems include storms, transport, and diffuse harvesting. Benefits include available nutrients, ample water, and Sun. Careful attention to details and use of saline agriculture fuel feedstocks are required to prevent anthropogenic disasters. It is shown that the potential for fuel-food feedstock halophyte production is high; based on test plot data, it could supply 421.4 Quad, or 94% of the 2004 world energy consumption and sequester carbon, with major impact on the Triangle of Conflicts.

Hendricks, Robert C.; Bushnell, Dennis M.

2007-01-01

28

Changes in cellular distribution regulate SKD1 ATPase activity in response to a sudden increase in environmental salinity in halophyte ice plant  

PubMed Central

Halophyte Mesembryanthemum crystallinum L. (ice plant) rapidly responds to sudden increases in salinity in its environment by activating specific salt-tolerant mechanisms. One major strategy is to regulate a series of ion transporters and proton pumps to maintain cellular Na+/K+ homeostasis. Plant SKD1 (suppressor of K+ transport growth defect 1) proteins accumulate in cells actively engaged in the secretory processes, and play a critical role in intracellular protein trafficking. Ice plant SKD1 redistributes from the cytosol to the plasma membrane hours after salt stressed. In combination with present knowledge of this protein, we suggest that stress facilitates SKD1 movement to the plasma membrane where ADP/ATP exchange occurs, and functions in the regulation of membrane components such as ion transporters to avoid ion toxicity. PMID:24390077

Jou, Yingtzy; Chiang, Chih-Pin; Yen, Hungchen Emilie

2013-01-01

29

Screening, isolation, and characterization of glycosyl-hydrolase-producing fungi from desert halophyte plants.  

PubMed

Fungal strains naturally occurring on the wood and leaves of the salt-excreting desert tree Tamarix were isolated and characterized for their ability to produce cellulose- and starch-degrading enzymes. Of the 100 isolates, six fungal species were identified by ITS1 sequence analysis. No significant differences were observed among taxa isolated from wood samples of different Tamarix species, while highly salt-tolerant forms related to the genus Scopulariopsis (an anamorphic ascomycete) occurred only on the phylloplane of T. aphylla. All strains had cellulase and amylase activities, but the production of these enzymes was highest in strain D, a Schizophyllum-commune-related form. This strain, when grown on pretreated Tamarix biomass, produced an enzymatic complex containing levels of filter paperase (414 +/- 16 IU/ml) that were higher than those of other S. commune strains. The enzyme complex was used to hydrolyze different lignocellulosic substrates, resulting in a saccharification rate ofpretreated milk thistle (73.5 +/- 1.2%) that was only 10% lower than that obtained with commercial cellulases. Our results support the use of Tamarix biomass as a useful source of cellulolytic and amylolytic fungi and as a good feedstock for the economical production of commercially relevant cellulases and amylases. PMID:25296445

Luziatelli, Francesca; Crognale, Silvia; D'Annibale, Alessandro; Moresi, Mauro; Petruccioli, Maurizio; Ruzzi, Maurizio

2014-03-01

30

Bio-insecticidal activities of halophytic plant extracts against Tribolium confusum (Coleoptera, Tenebrionidae).  

PubMed

Salt marsh plants were tested for their insecticidal activities against larvae of the confused flour beetle Tribolium confusum (Tenebrionidae). 16 aerial part extracts were obtained using organic solvents of increasing polarity and tested for their anti-feedant and toxicity effects. Responses varied with plant material and extract type. Ethyl acetate extracts of F. laevis, S. echioides and. T. boveana and petroleum ether extract of F. laevis presented, anti-feedant property. However, S. fructicosa seemed to be attractive to the tested flour beetle. Mortalities of 97, 87, 97 and 80% were observed by using respectively ethyl acetate extracts of F. laevis, S. echioides and T. boveana and petroleum ether extract of F. laevis, when applied at a dose of 1%, mixed with the insect diet. This preliminary study showed that F. laevis, S. echioides and T. boveana presented potential bio-insecticidal activity with ethyl acetate extracts, similar result was found with petroleum ether extract of F. laevis. More complementary studies are needed for the use of these extracts to control T. confusum. PMID:16628919

Saïdana, D; Ben Halima-Kamel, M; Ben Tiba, B; Haouas, D; Mahjoub, M A; Mighri, Z; Helal, A N

2005-01-01

31

Development of sheep and goat production system based on the use of salt-tolerant plants and marginal resources in the United Arab Emirates  

Microsoft Academic Search

In the United Arab Emirates (UAE), several programs and centers have been established to study and evaluate halophytic and salt-tolerant plant communities. A large number of halophytic species, acquired from various parts of the world, have been evaluated and field-tested under salt and seawater irrigation regimes at UAE University and International Center for Biosaline Agriculture (ICBA). Among these species, Sporobolus

S. A. Al-Shorepy; G. A. Alhadrami; A. I. El Awad

2010-01-01

32

Habitat specificity of a threatened and endemic, cliff-dwelling halophyte  

PubMed Central

Coastal areas and other saline environments are major contributors to regional and global biodiversity patterns. In these environments, rapidly changing gradients require highly specialized plants like halophytes. In European coastal cliff-tops, rocky and sandy seashores, and saltmarshes, typical halophytes from the genus Limonium are commonly found. Among them, the aneuploid tetraploid (2n = 4x = 35, 36, 37) Limonium multiflorum, endemic to the west coast of Portugal, is an interesting case study for investigating the ecology and conservation of a halophyte agamospermic species. Although it is listed in the IUCN red list of threatened species, information on its population size or rarity, as well as its ecology, in some respects is still unknown. Field surveys in the largest known population were performed (Raso cape, Portugal) in order to determine habitat requirements and conservation status. A total of 88 quadrats were monitored, 43 of which contained at least one L. multiflorum individual. For each sampled quadrat, four abiotic and four biotic variables as well as two spatially derived variables were recorded. Principal component analysis and cluster analysis showed narrow habitat specificity for this species which appeared to be intolerant to competition with invasive alien plants. We conclude that in situ conservation in a local ‘hotspot’ of this rare and vulnerable species emerges as a priority in order to ensure that biodiversity is not lost. PMID:24942513

Caperta, Ana D.; Espirito-Santo, M. Dalila; Silva, Vasco; Ferreira, Ana; Paes, Ana P.; Rois, Ana S.; Costa, Jose C.; Arsenio, Pedro

2014-01-01

33

On the distribution and evaluation of Na, Mg and Cl in leaves of selected halophytes  

NASA Astrophysics Data System (ADS)

Diverse physiological, biochemical and morphological adaptations enable plants to survive in extreme saline environments where osmotic and ionic stresses limit growth and development. Halophytes are salt-tolerant plants that can withstand extraordinarily high levels of Na and Cl in their leaves. The tissue and cellular distribution patterns of salt ions can be linked to the underlying mechanisms of salt tolerance. Application of fast, reliable, multi-elemental and quantitative techniques such as micro-proton-induced X-ray emission (micro-PIXE) will significantly contribute to and accelerate studies of plant salt tolerance, especially as micro-PIXE also provides spatially resolved quantitative data for light elements, such as Na and Mg. The spatial concentration distributions of Na, Mg, Cl, K, P and S in leaves of four halophytes (Bassia indica, Atriplex prostrata, Spartina maritima and Limonium angustifolium) were determined using micro-PIXE, to study the salt-tolerance strategies of the selected halophytes. Different distribution patterns of the studied elements were seen in the leaves; however, in all four of these plant species, Na was excluded from photosynthetically active chlorophyl tissues. With the exception of L. angustifolium, Cl, P and S contents (representing chloride, phosphate and sulphate ionic forms, respectively) did not ensure charge balance in the leaves, which suggests other anionic compounds, such as nitrate and organic anions, have crucial roles in maintaining electroneutrality in these halophytes. By increasing soil salinisation worldwide, the possibility to reliably complement spatial distributions of Na, Mg, Cl, K, P and S with plant structural morphology will contribute significantly to our understanding of plant tolerance mechanisms at the tissue and cell levels. In addition, these kinds of studies are of particular value for designing crop plants with high salt tolerance and for the development of phytoremediation technologies.

Pongrac, Paula; Vogel-Mikuš, Katarina; Regvar, Marjana; Kaligari?, Mitja; Vavpeti?, Primož; Kelemen, Mitja; Grlj, Nataša; Shelef, Oren; Golan-Goldhirsh, Avi; Rachmilevitch, Shimon; Pelicon, Primož

2013-07-01

34

Manipulating the antioxidant capacity of halophytes to increase their cultural and economic value through saline cultivation.  

PubMed

Halophytes, salt-tolerant plants, are a source of valuable secondary metabolites with potential economic value. The steady-state pools of many stress-related metabolites are already enhanced in halophytes when compared with glycophytes, but growth under conditions away from the optimum can induce stress and consequently result in changes to secondary metabolites such as antioxidants. However, direct evidence for increasing the concentration of valuable secondary metabolites as a consequence of altering the salinity of the growing environment still remains equivocal. To address this, we analysed a range of metabolites with antioxidant capacity (including total phenols, flavonoids, ascorbate, reduced/oxidized glutathione and reactive oxygen species scavenging enzymes) in seedlings and plants from different families (Amaranthaceae, Brassicaceae, Plantaginaceae and Rhizophoraceae) and habitats grown under different salt concentrations. We show that it is possible to manipulate the antioxidant capacity of plants and seedlings by altering the saline growing environment, the length of time under saline cultivation and the developmental stage. Among the species studied, the halophytes Tripolium pannonicum, Plantago coronopus, Lepidium latifolium and Salicornia europaea demonstrated the most potential as functional foods or nutraceuticals. PMID:25125698

Boestfleisch, Christian; Wagenseil, Niko B; Buhmann, Anne K; Seal, Charlotte E; Wade, Ellie Merrett; Muscolo, Adele; Papenbrock, Jutta

2014-01-01

35

Manipulating the antioxidant capacity of halophytes to increase their cultural and economic value through saline cultivation  

PubMed Central

Halophytes, salt-tolerant plants, are a source of valuable secondary metabolites with potential economic value. The steady-state pools of many stress-related metabolites are already enhanced in halophytes when compared with glycophytes, but growth under conditions away from the optimum can induce stress and consequently result in changes to secondary metabolites such as antioxidants. However, direct evidence for increasing the concentration of valuable secondary metabolites as a consequence of altering the salinity of the growing environment still remains equivocal. To address this, we analysed a range of metabolites with antioxidant capacity (including total phenols, flavonoids, ascorbate, reduced/oxidized glutathione and reactive oxygen species scavenging enzymes) in seedlings and plants from different families (Amaranthaceae, Brassicaceae, Plantaginaceae and Rhizophoraceae) and habitats grown under different salt concentrations. We show that it is possible to manipulate the antioxidant capacity of plants and seedlings by altering the saline growing environment, the length of time under saline cultivation and the developmental stage. Among the species studied, the halophytes Tripolium pannonicum, Plantago coronopus, Lepidium latifolium and Salicornia europaea demonstrated the most potential as functional foods or nutraceuticals. PMID:25125698

Boestfleisch, Christian; Wagenseil, Niko B.; Buhmann, Anne K.; Seal, Charlotte E.; Wade, Ellie Merrett; Muscolo, Adele; Papenbrock, Jutta

2014-01-01

36

Growth promotion of the seawater-irrigated oilseed halophyte Salicornia bigelovii inoculated with mangrove rhizosphere bacteria and halotolerant Azospirillum spp  

Microsoft Academic Search

Inoculation of the oilseed halophyte Salicornia bigelovii Torr. with eight species of halotolerant bacteria, grown in seawater-irrigated pots under environmental conditions native\\u000a to the plant's habitat, resulted in significant plant growth promotion by the end of the growing season, 8–11?months later.\\u000a Statistical analysis demonstrated that inoculation with Azospirillum halopraeferens, a mixture of two Azospirillum brasilense strains, a mixture of Vibrio

Y. Bashan; M. Moreno; E. Troyo

2000-01-01

37

Germination of Dimorphic Seeds of the Desert Annual Halophyte Suaeda aralocaspica (Chenopodiaceae), a C4 Plant without Kranz Anatomy  

PubMed Central

Background and Aims Suaeda aralocaspica is a C4 summer annual halophyte without Kranz anatomy that is restricted to the deserts of central Asia. It produces two distinct types of seeds that differ in colour, shape and size. The primary aims of the present study were to compare the dormancy and germination characteristics of dimorphic seeds of S. aralocaspica and to develop a conceptual model of their dynamics. Methods Temperatures simulating those in the natural habitat of S. aralocaspica were used to test for primary dormancy and germination behaviour of fresh brown and black seeds. The effects of cold stratification, gibberellic acid, seed coat scarification, seed coat removal and dry storage on dormancy breaking were tested in black seeds. Germination percentage and recovery responses of brown seeds, non-treated black seeds and 8-week cold-stratified black seeds to salt stress were tested. Key Results Brown seeds were non-dormant, whereas black seeds had non-deep Type 2 physiological dormancy (PD). Germination percentage and rate of germination of brown seeds and of variously pretreated black seeds were significantly higher than those of non-pretreated black seeds. Exposure of seeds to various salinities had significant effects on germination, germination recovery and induction into secondary dormancy. A conceptual model is presented that ties these results together and puts them into an ecological context. Conclusions The two seed morphs of S. aralocaspica exhibit distinct differences in dormancy and germination characteristics. Suaeda aralocaspica is the first cold desert halophyte for which non-deep Type 2 PD has been documented. PMID:18772148

Wang, Lei; Huang, Zhenying; Baskin, Carol C.; Baskin, Jerry M.; Dong, Ming

2008-01-01

38

Growth and physiological adaptation of whole plants and cultured cells from a halophyte turf grass under salt stress.  

PubMed

Understanding the mechanisms used by halophytic members of the Poaceae to cope with salt stress will contribute to the knowledge necessary to genetically engineer salt-tolerant crops. In this study, we identified a genotype of Sporobolus virginicus, a halophytic turf grass collected in Japan, and investigated its growth rate, ion concentration and secretion, and proline concentration in comparison with the reported properties of genotypes collected from the USA, South Africa and Egypt. Surprisingly, the Japanese genotype showed a salinity tolerance up to 1.5 M NaCl, a 3-fold higher concentration than seawater salinity. Shoot growth was stimulated by 100 mM NaCl and root growth was stimulated at salinities of up to 1 M NaCl. Accumulation of Na(+) and CI(-) in shoots and roots was rapidly elevated by salinity stress but did not exceed the levels required for osmotic adjustment, due in part to ion secretion by salt glands, which are present in genotypes of S. virginicus. However, the Japanese genotypes accumulated K(+) to a higher level than other genotypes, resulting in a relatively high K(+)/Na(+) ratio even under salinity stress. An increase in proline concentration was observed that was proportional to the NaCl concentration in the culture solution and might partially account for osmotic adjustment in the shoots. We also generated and characterized cultured cells of S. virginicus. In 500 mM NaCl, the cultured cells showed an enhanced growth compared with cultured cells of rice. The concentration of Na(+) and CI(-) in the cultured cells in 300-500 mM NaCl was lower than in 100 mM NaCl. Cultured cells of S. virginicus accumulated proline to higher levels than rice cells cultured under salinity stress. The active regulation of Na(+), Cl(-) and K(+) influx/efflux and proline accumulation might be involved in salt tolerance mechanisms at the cellular level as well as in planta. PMID:25024277

Tada, Yuichi; Komatsubara, Shiho; Kurusu, Takamitsu

2014-01-01

39

Growth and physiological adaptation of whole plants and cultured cells from a halophyte turf grass under salt stress  

PubMed Central

Understanding the mechanisms used by halophytic members of the Poaceae to cope with salt stress will contribute to the knowledge necessary to genetically engineer salt-tolerant crops. In this study, we identified a genotype of Sporobolus virginicus, a halophytic turf grass collected in Japan, and investigated its growth rate, ion concentration and secretion, and proline concentration in comparison with the reported properties of genotypes collected from the USA, South Africa and Egypt. Surprisingly, the Japanese genotype showed a salinity tolerance up to 1.5 M NaCl, a 3-fold higher concentration than seawater salinity. Shoot growth was stimulated by 100 mM NaCl and root growth was stimulated at salinities of up to 1 M NaCl. Accumulation of Na+ and CI? in shoots and roots was rapidly elevated by salinity stress but did not exceed the levels required for osmotic adjustment, due in part to ion secretion by salt glands, which are present in genotypes of S. virginicus. However, the Japanese genotypes accumulated K+ to a higher level than other genotypes, resulting in a relatively high K+/Na+ ratio even under salinity stress. An increase in proline concentration was observed that was proportional to the NaCl concentration in the culture solution and might partially account for osmotic adjustment in the shoots. We also generated and characterized cultured cells of S. virginicus. In 500 mM NaCl, the cultured cells showed an enhanced growth compared with cultured cells of rice. The concentration of Na+ and CI? in the cultured cells in 300–500 mM NaCl was lower than in 100 mM NaCl. Cultured cells of S. virginicus accumulated proline to higher levels than rice cells cultured under salinity stress. The active regulation of Na+, Cl? and K+ influx/efflux and proline accumulation might be involved in salt tolerance mechanisms at the cellular level as well as in planta. PMID:25024277

Tada, Yuichi; Komatsubara, Shiho; Kurusu, Takamitsu

2014-01-01

40

RING-type ubiquitin ligase McCPN1 catalyzes UBC8-dependent protein ubiquitination and interacts with Argonaute 4 in halophyte ice plant.  

PubMed

RING-type copines are a small family of plant-specific RING-type ubiquitin ligases. They contain an N-terminal myristoylation site for membrane anchoring, a central copine domain for substrate recognition, and a C-terminal RING domain for E2 docking. RING-type copine McCPN1 (copine1) from halophyte ice plant (Mesembryanthemum crystallinum L.) was previously identified from a salt-induced cDNA library. In this work, we characterize the activity, expression, and localization of McCPN1 in ice plant. An in vitro ubiquitination assay of McCPN1 was performed using two ice plant UBCs, McUBC1 and McUBC2, characterized from the same salt-induced cDNA library. The results showed that McUBC2, a member of the UBC8 family, stimulated the autoubiquitination activity of McCPN1, while McUBC1, a homolog of the UBC35 family, did not. The results indicate that McCPN1 has selective E2-dependent E3 ligase activity. We found that McCPN1 localizes primarily on the plasma membrane and in the nucleus of plant cells. Under salt stress, the accumulation of McCPN1 in the roots increases. A yeast two-hybrid screen was used to search for potential McCPN1-interacting partners using a library constructed from salt-stressed ice plants. Screening with full-length McCPN1 identified several independent clones containing partial Argonaute 4 (AGO4) sequence. Subsequent agro-infiltration, protoplast two-hybrid analysis, and bimolecular fluorescence complementation assay confirmed that McCPN1 and AGO4 interacted in vivo in the nucleus of plant cells. The possible involvement of a catalyzed degradation of AGO4 by McCPN1 in response to salt stress is discussed. PMID:24811676

Li, Chang-Hua; Chiang, Chih-Pin; Yang, Jun-Yi; Ma, Chia-Jou; Chen, Yu-Chan; Yen, Hungchen Emilie

2014-07-01

41

Isolation and characterization of endophytic plant growth-promoting (PGPB) or stress homeostasis-regulating (PSHB) bacteria associated to the halophyte Prosopis strombulifera.  

PubMed

This study was designed to isolate and characterize endophytic bacteria from halophyte Prosopis strombulifera grown under extreme salinity and to evaluate in vitro the bacterial mechanisms related to plant growth promotion or stress homeostasis regulation. Isolates obtained from P. strombulifera were compared genotypically by BOX-polymerase chain reaction, grouped according to similarity, and identified by amplification and partial sequences of 16S DNAr. Isolates were grown until exponential growth phase to evaluate the atmospheric nitrogen fixation, phosphate solubilization, siderophores, and phytohormones, such as indole-3-acetic acid, zeatin, gibberellic acid and abscisic acid production, as well as antifungal, protease, and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. A total of 29 endophytic strains were grouped into seven according to similarity. All bacteria were able to grow and to produce some phytohormone in chemically defined medium with or without addition of a nitrogen source. Only one was able to produce siderophores, and none of them solubilized phosphate. ACC deaminase activity was positive for six strains. Antifungal and protease activity were confirmed for two of them. In this work, we discuss the possible implications of these bacterial mechanisms on the plant growth promotion or homeostasis regulation in natural conditions. PMID:19655138

Sgroy, Verónica; Cassán, Fabricio; Masciarelli, Oscar; Del Papa, María Florencia; Lagares, Antonio; Luna, Virginia

2009-11-01

42

Medicinal halophytes: potent source of health promoting biomolecules with medical, nutraceutical and food applications.  

PubMed

Salt-tolerant plants grow in a wide variety of saline habitats, from coastal regions, salt marshes and mudflats to inland deserts, salt flats and steppes. Halophytes living in these extreme environments have to deal with frequent changes in salinity level. This can be done by developing adaptive responses including the synthesis of several bioactive molecules. Consequently, several salt marsh plants have traditionally been used for medical, nutritional, and even artisanal purposes. Currently, an increasing interest is granted to these species because of their high content in bioactive compounds (primary and secondary metabolites) such as polyunsaturated fatty acids, carotenoids, vitamins, sterols, essential oils (terpenes), polysaccharides, glycosides, and phenolic compounds. These bioactive substances display potent antioxidant, antimicrobial, anti-inflammatory, and anti-tumoral activities, and therefore represent key-compounds in preventing various diseases (e.g. cancer, chronic inflammation, atherosclerosis and cardiovascular disorder) and ageing processes. The ongoing research will lead to the utilisation of halophytes as a new source of healthy products as functional foods, nutraceuticals or active principles in several industries. This contribution focuses on the ethnopharmacological uses of halophytes in traditional medicine and reviews recent investigations on their biological activities and nutraceuticals. The work is distributed according to the different families of nutraceuticals (lipids, vitamins, proteins, glycosides, phenolic compounds, etc.) discussing the analytical techniques employed for their determination. Information about the claimed health promoting effects of the different families of nutraceuticals is also provided together with data on their application. PMID:22129270

Ksouri, Riadh; Ksouri, Wided Megdiche; Jallali, Inès; Debez, Ahmed; Magné, Christian; Hiroko, Isoda; Abdelly, Chedly

2012-12-01

43

Assessment of the potential of halophytes as energy crops for the electric utility industry. Final report  

Microsoft Academic Search

This technical report assesses and estimates the potential of selected halophytes as future renewable energy resources, especially by US electric utilities, and familiarizes nonspecialists with research and development problems that must be resolved before these energy sources can become dependable supplies of energy. A literature search related to both indigenous and exotic species of halophytes has been done and appropriate

Goodin

1984-01-01

44

The effect of competition and edaphic conditions on the establishment of halophytes on brine effected soils  

Microsoft Academic Search

In order to test the feasibility of using native halophytes to reclaim brinecontaminated soil, seedlings of five inland halophytes, Atriplexprostrata, Hordeum jubatum, Salicornia europaea, Spergularia marina, and Suaeda calceoliformis, were planted at threedensities on a site near Athens, Ohio which had been contaminated by oilwell brine water. Ten replicates of each density treatment weretransplanted on two distinct areas of high

Carolyn Howes Keiffer; Irwin A. Ungar

2001-01-01

45

A comparative study of the early osmotic, ionic, redox and hormonal signaling response in leaves and roots of two halophytes and a glycophyte to salinity.  

PubMed

Salt stress is one of the most important abiotic stress factors affecting plant growth and productivity in natural ecosystems. In this study, we aimed at determining possible differences between salt tolerant and salt sensitive species in early (within 72 h) salt stress response in leaves and roots. To this purpose, we subjected three Brassicaceae species, namely two halophytes-Cakile maritima and Thellungiella salsuginea-and a glycophyte-Arabidopsis thaliana- to short-term salt stress (400 mM NaCl). The results indicate that the halophytes showed a differential osmotic and ionic response together with an early and transient oxidative burst, which was characterized by enhanced hydrogen peroxide levels and subsequent activation of antioxidant defenses in both leaves and roots. In addition, the halophytes displayed enhanced accumulation of abscisic acid, jasmonic acid (JA) and ACC (aminocyclopropane-1-carboxylic acid, the precursor of ethylene) in leaves and roots, as compared to A. thaliana under salt stress. Moreover, the halophytes showed enhanced expression of ethylene response factor1 (ERF1), the convergence node of the JA and ethylene signaling pathways in both leaves and roots upon exposure to salt stress. In conclusion, we show that the halophytes C. maritima and T. salsuginea experience an early oxidative burst, improved antioxidant defenses and hormonal response not only in leaves but also in roots, in comparison to the glycophyte A. thaliana. This differential signaling response converging, at least in part, into increased ERF1 expression in both above- and underground tissues seems to underlay, at least in part, the enhanced tolerance of the two studied halophytes to salt stress. PMID:25156490

Ellouzi, Hasna; Hamed, Karim Ben; Hernández, Iker; Cela, Jana; Müller, Maren; Magné, Christian; Abdelly, Chedly; Munné-Bosch, Sergi

2014-12-01

46

Genetically Altered Plant Species  

NASA Technical Reports Server (NTRS)

Researchers in Robert Ferl's lab at the University of Florida in Gainesville, genetically altered this Arabdopsis Thaliana (a brassica species) plant to learn how extreme environments, such as the low atmospheric pressure on Mars, affect plant genes. They inserted green fluorescent protein (GFP) near the on/off switches for anoxia and drought genes. When those genes were turned on after exposure to reduced atmospheric pressure, GFP was turned on as well, causing cells expressing those genes to glow green under a blue light. The natural fluorescence of chlorophyll accounts for the red glow.

2003-01-01

47

Membrane-forming lipids of wild halophytes growing under the conditions of Prieltonie of South Russia.  

PubMed

The composition of membrane-forming lipids has been examined for 10 wild halophyte species growing in southern Russian on alkaline soil. The plants belong to seven taxa of family rank: by their life form, which are semi-shrubs, herbaceous annuals, and perennial plants; their salt tolerance, which are classified as the euhalophytes, crynohalophytes, and glycohalophytes; and by their sensitivity to water, classifications of mesoxerophytes and xeromesophytes. Parallels have been found between the lipid composition and the ecological status of the plants. It has also been revealed that the similarity in the glyco- and phospholipid composition of different plant groups relates to the water factor and the type of salt accumulation, respectively. The fatty acid compositions of the examined plants is determined at the species level. PMID:24890389

Rozentsvet, Olga A; Nesterov, Victor N; Bogdanova, Elena S

2014-09-01

48

Responses of five Mediterranean halophytes to seasonal changes in environmental conditions  

PubMed Central

In their natural habitats, different mechanisms may contribute to the tolerance of halophytes to high soil salinity and other abiotic stresses, but their relative contribution and ecological relevance, for a given species, remain largely unknown. We studied the responses to changing environmental conditions of five halophytes (Sarcocornia fruticosa, Inula crithmoides, Plantago crassifolia, Juncus maritimus and J. acutus) in a Mediterranean salt marsh, from summer 2009 to autumn 2010. A principal component analysis was used to correlate soil and climatic data with changes in the plants' contents of chemical markers associated with stress responses: ions, osmolytes, malondialdehyde (MDA, a marker of oxidative stress) and antioxidant systems. Stress tolerance in S. fruticosa, I. crithmoides and P. crassifolia (all succulent dicots) seemed to depend mostly on the transport of ions to aerial parts and the biosynthesis of specific osmolytes, whereas both Juncus species (monocots) were able to avoid accumulation of toxic ions, maintaining relatively high K+/Na+ ratios. For the most salt-tolerant taxa (S. fruticosa and I. crithmoides), seasonal variations of Na+, Cl?, K+ and glycine betaine, their major osmolyte, did not correlate with environmental parameters associated with salt or water stress, suggesting that their tolerance mechanisms are constitutive and relatively independent of external conditions, although they could be mediated by changes in the subcellular compartmentalization of ions and compatible osmolytes. Proline levels were too low in all the species to possibly have any effect on osmotic adjustment. However—except for P. crassifolia—proline may play a role in stress tolerance based on its ‘osmoprotectant’ functions. No correlation was observed between the degree of environmental stress and the levels of MDA or enzymatic and non-enzymatic antioxidants, indicating that the investigated halophytes are not subjected to oxidative stress under natural conditions and do not, therefore, need to activate antioxidant defence mechanisms. PMID:25139768

Gil, Ricardo; Bautista, Inmaculada; Boscaiu, Monica; Lidón, Antonio; Wankhade, Shantanu; Sánchez, Héctor; Llinares, Josep; Vicente, Oscar

2014-01-01

49

Comparative study of rhizobacterial community structure of plant species in oil-contaminated soil.  

PubMed

In this study, the identity and distribution of plants and the structure of their associated rhizobacterial communities were examined in an oil-contaminated site. The number of plant species that formed a community or were scattered was 24. The species living in soil highly contaminated with total petroleum hydrocarbon (TPH) (9,000-4,5000 mg/g-soil) were Cynodon dactylon, Persicaria lapathifolia, and Calystegia soldanella (a halophytic species). Among the 24 plant species, the following have been known to be effective for oil removal: C. dactylon, Digitaria sanguinalis, and Cyperus orthostachyus. Denaturing gradient gel electrophoresis (DGGE) profile analysis showed that the following pairs of plant species had highly similar (above 70%) rhizobacterial community structures: Artemisia princeps and Hemistepta lyrata; C. dactylon and P. lapathifolia; Carex kobomugi and Cardamine flexuosa; and Equisetum arvense and D. sanguinalis. The major groups of rhizobacteria were Betaproteobacteria, Gamma-proteobacteria, Chloroflexi, Actinobacteria, and unknown. Based on DGGE analysis, P. lapathifolia, found for the first time in this study growing in the presence of high TPH, may be a good species for phytoremediation of oil-contaminated soils and in particular, C. soldanella may be useful for soils with high TPH and salt concentrations. Overall, this study suggests that the plant roots, regardless of plant species, may have a similar influence on the bacterial community structure in oil-contaminated soil. PMID:20890100

Lee, Eun-Hee; Cho, Kyong-Suk; Kim, Jaisoo

2010-09-01

50

EDTA-enhanced phytoremediation of lead-contaminated soil by the halophyte Sesuvium portulacastrum.  

PubMed

The low bioavailability of Pb and low number of Pb-tolerant plant species represent an important limitation for Pb phytoextraction. It was recently suggested that halophyte plant species may be a promising material for this purpose, especially in polluted salt areas while Pb mobility may be improved by synthetic chelating agents. This study aims to evaluate Pb extraction by the halophyte Sesuvium portulacastrum in relation to the impact of EDTA application. Seedling were cultivated during 60 days on Pb artificially contaminated soil (200, 400, and 800 ppm Pb) in the presence or in the absence of EDTA (3 g kg(-1) soil). Results showed that upon to 400 ppm, Pb had no impact on plant growth. However, exogenous Pb induce a decrease in shoot K(+) while it increased shoot Mg(2+) and had no impact on shoot Ca(2+) concentrations. Lead concentration in the shoots increased with increasing external Pb doses reaching 1,390 ppm in the presence of 800 ppm lead in soil. EDTA addition had no effect on plant growth but strongly increased Pb accumulation in the shoot which increased from 1,390 ppm in the absence of EDTA to 3,772 ppm in EDTA-amended plants exposed to 800 ppm exogenous Pb. Both Pb absorption and translocation from roots to shoots were significantly enhanced by EDTA application, leading to an increase in the total amounts of extracted Pb per plant. These data suggest that S. portulacastrum is very promising species for decontamination of Pb(2+)-contaminated soil and that its phytoextraction potential was significantly enhanced by addition of EDTA to the polluted soil. PMID:24604274

Zaier, Hanen; Ghnaya, Tahar; Ghabriche, Rim; Chmingui, Walid; Lakhdar, Abelbasset; Lutts, Stanley; Abdelly, Chedly

2014-06-01

51

High apoplastic solute concentrations in leaves alter water relations of the halophytic shrub, Sarcobatus vermiculatus  

Microsoft Academic Search

Predawn plant water potential (Ww) is used to estimate soil moisture available to plants because plants are expected to equilibrate with the root-zone Ww. Although this equilibrium assumption provides the basis for interpreting many physiological and ecological param- eters, much work suggests predawn plant Ww is often more negative than root-zone soil Ww. For many halophytes even when soils are

J. J. James; N. N. Alder; K. H. Muhling; A. E. Lauchli; K. A. Shackel; L. A. Donovan; J. H. Richards

2006-01-01

52

Abscisic acid has contrasting effects on salt excretion and polyamine concentrations of an inland and a coastal population of the Mediterranean xero-halophyte species Atriplex halimus  

PubMed Central

Background and Aims Different populations of the Mediterranean xerohalophyte species Atriplex halimus exhibit different levels of resistance to salt and osmotic stress depending on the nature of the osmocompatible solute they accumulate. There is, however, no conclusive description of the involvement of abscisic acid (ABA) in the plant response to NaCl or osmotic stress in this species. Methods Seedlings issued from an inland water-stress-resistant population (Sbikha) and from a coastal salt-resistant one (Monastir) were exposed in nutrient solutions to NaCl (40 or 160 mm) or to 15 % PEG for 1 d and 10 d in the presence or absence of 50 µm ABA. Key Results Plants from Sbikha accumulated higher amounts of ABA in response to osmotic stress than those of Monastir, while an opposite trend was recorded for NaCl exposure. Exogenous ABA improved osmotic stress resistance in Monastir through an improvement in the efficiency of stomatal conductance regulation. It also improved NaCl resistance in Sbikha through an increase in sodium excretion through the external bladders. It is suggested that polyamines (spermidine and spermine) are involved in the salt excretion process and that ABA contributes to polyamine synthesis as well as to the conversion from the bound and conjugated to the free soluble forms of polyamine. Proline accumulated in response to osmotic stress and slightly increased in response to ABA treatment while glycinebetaine accumulated in response to salinity and was not influenced by ABA. Conclusions It is concluded that ABA is involved in both salt and osmotic stress resistance in the xerohalophyte species Atriplex halimus but that it acts on different physiological cues in response to those distinct environmental constraints. PMID:19666900

Ben Hassine, A.; Ghanem, M. E.; Bouzid, S.; Lutts, S.

2009-01-01

53

Z .Aquaculture 175 1999 255268 Halophytes for the treatment of saline aquaculture  

E-print Network

the feasibility of using salt-tolerant plants halophytes as biofilters to remove nutrients from saline aquaculture salinity was increased with NaCl to make salinity treatments of 0.5, 10 and 35 ppt. The plant­soil system plant evapotranspiration. It could be extended to saline effluent streams if suitable, salt

Smith, Steven E.

54

Halophytes, Algae, and Bacteria Food and Fuel Feedstocks  

NASA Technical Reports Server (NTRS)

The constant, increasing demand for energy, freshwater, and food stresses our ability to meet these demands within reasonable cost and impact on climate while sustaining quality of life. This environmental Triangle of Conflicts between energy, food, and water--while provoked by anthropogenic monetary and power struggles--can be resolved through an anthropogenic paradigm shift in how we produce and use energy, water, and food. With world population (6.6 billion) projected to increase 40 percent in 40 to 60 yr, proper development of saline agriculture and aquaculture is required, as 43 percent of the Earth's landmass is arid or semi-arid and 97 percent of the Earth's water is seawater. In light of this, we seek fuel alternatives in plants that thrive in brackish and saltwater with the ability to survive in arid lands. The development and application of these plants (halophytes) become the primary focus. Herein we introduce some not-so-familiar halophytes and present a few of their benefits, cite a few research projects (including some on the alternatives algae and bacteria), and then set theoretical limits on biomass production followed by projections in terms of world energy demands. Based on diverse arid lands with a total size equivalent to the Sahara Desert (8.6(exp 8) ha, or 2.1(exp 9) acres), these projections show that halophyte agriculture and algae systems can provide for the projected world energy demand.

Hendricks, R. C.; Bushnell, D. M.

2009-01-01

55

The Ice Plant Cometh: Lessons in Abiotic Stress Tolerance  

Microsoft Academic Search

Mesembryanthemum crystallinum, the common ice plant, provides a model for the developmentally and environmentally inducible shift from C3 photosynthesis to Crassulacean acid metabolism. Study of its halophytic (salt tolerant) nature has also yielded crucial insights into abiotic stress biology. In addition, the ice plant serves as an anchor species for genomic studies in the order Caryophyllales in which very few

Hans J. Bohnert; John C. Cushman

2000-01-01

56

How successful are plant species reintroductions?  

Microsoft Academic Search

Reintroduction of native species has become increasingly important in conservation worldwide for recovery of rare species and restoration purposes. However, few studies have reported the outcome of reintroduction efforts in plant species. Using data from the literature combined with a questionnaire survey, this paper analyses 249 plant species reintroductions worldwide by assessing the methods used and the results obtained from

Sandrine Godefroid; Carole Piazza; Graziano Rossi; Stéphane Buord; Albert-Dieter Stevens; Ruth Aguraiuja; Carly Cowell; Carl W. Weekley; Gerd Vogg; José M. Iriondo; Isabel Johnson; Bob Dixon; Doria Gordon; Sylvie Magnanon; Bertille Valentin; Kristina Bjureke; Rupert Koopman; Magdalena Vicens; Myriam Virevaire; Thierry Vanderborght

2011-01-01

57

ALLEVIATION OF SALT-INDUCED SEED DORMANCY IN THE PERENNIAL HALOPHYTE CRITHMUM MARITIMUM L. (APIACEAE)  

Microsoft Academic Search

Crithmum maritimum L. (Apiaceae) is a perennial local oilseed halophyte. For a better understanding of the eco-physiology of salt tolerance at the germinative stage of this species, we investigate here the effects of nitrate, thiourea, and priming on its seed germination under saline conditions. Germination was strongly inhibited by increasing salinity. While nitrate supply was effective in alleviating salt-induced seed

ABDALLAH ATIA; AHMED DEBEZ; MOKDED RABHI; REHMAN ATHAR; CHEDLY ABDELLY

58

SELECTING PLANT SPECIES FOR PESTICIDE REGISTRATION TESTS  

EPA Science Inventory

Current test protocols used by the US EPA for the registration of pesticides examines plant responses of 10 crop species but may not examine regionally important native plants or crops. In order to test the efficiency of current test protocols we selected six native plant species...

59

A salinity-induced gene from the halophyte M. crystallinum encodes a glycolytic enzyme, cofactor-independent phosphoglyceromutase  

Microsoft Academic Search

In the facultative halophyte Mesembryanthemum crystallinum (ice plant), salinity stress triggers significant changes in gene expression, including increased expression of mRNAs encoding enzymes involved with osmotic adaptation to water stress and the crassulacean acid metabolism (CAM) photosynthetic pathway. To investigate adaptive stress responses in the ice plant at the molecular level, we generated a subtracted cDNA library from stressed plants

Nancy R. Forsthoefel; Daniel M. Vernon; John C. Cushman

1995-01-01

60

Atmospheric and Soil Carbon and Halophytes  

NASA Technical Reports Server (NTRS)

World population is anticipated to grow 40% within 40-50 years (2008 baseline) with unprecedented demands for energy, food, freshwater, and clean environments. At 43% of the total landmass, exploiting the Earth's arid and semi-arid lands becomes a matter of necessity. Compared with glycophyte agriculture, we view seawater and brackish water halophyte saline agriculture in its nascent stage and see the need to explore and farm on a massive scale. Halophyte farming costs should be the same as glycophyte cellulosic biomass farming; processing for cellulosic matter should also be applicable. Halophyte life cycle analyses (LCA) within the fueling debate are incomplete, yet glycophyte LCA favors biomass fueling. The Biomass Revolution is in progress. The capacity, cost, and logistics required for biomass replacement of petroleum-based fuels, however, will require all feedstock sources and regional cooperative productivity, technical investments, and both the participation and cooperation of the American farmer and global farm community.

Hendricks, Robert C.; Bushnell, Dennis M.

2011-01-01

61

Atmospheric and Soil Carbon and Halophytes  

NASA Technical Reports Server (NTRS)

World population is anticipated to grow 40% within 40-50 years with unprecedented demands for energy, food, freshwater, and clean environments. At 43% of the total landmass, exploiting the Earth s arid and semi-arid lands becomes a matter of necessity. Compared with glycophyte agriculture, we view seawater and brackish water halophyte saline agriculture in its nascent stage and see the need to explore and farm on a massive scale. Halophyte farming costs should be the same as glycophyte cellulosic biomass farming; processing for cellulosic matter should also be applicable. Halophyte life cycle analyses (LCA) within the fueling debate are incomplete, yet glycophyte LCA favors biomass fueling. The Biomass Revolution is in progress. The capacity, cost, and logistics required for biomass replacement of petroleum-based fuels, however, will require all feedstock sources and regional cooperative productivity, technical investments, and both the participation and cooperation of the American farmer and global farm community

Hendricks, Robert C.; Bushnell, Dennis M.

2010-01-01

62

The Invasive Plant Species Education Guide  

ERIC Educational Resources Information Center

To help high school students gain a solid understanding of invasive plant species, university faculty and students from the University of Wisconsin-Stout (UW-Stout) and a local high school teacher worked together to develop the Invasive Plant Species (IPS) Education Guide. The IPS Education Guide includes nine lessons that give students an…

Mason, Kevin; James, Krista; Carlson, Kitrina; D'Angelo, Jean

2010-01-01

63

Chapter 5 PotentiallyVulnerable Species: Plants  

E-print Network

Service Region 5 Sensitive Species.The Forest Service Sensitive (FSS) list is intended as an early alert it becoming listed as threat- ened or endangered. FSS plants are protected through the implementation federally listed nor Forest Service Sensitive species. These are plants which currently do not warrant FSS

Standiford, Richard B.

64

[Invasion and its effects of xerarch halophytes in reclaimed tidal wetlands].  

PubMed

With the reclaimed tidal wetland of Chongming Dongtan in Shanghai as a case, and based on the landscape pattern analysis of colored infrared aerial photographs and field survey, this paper studied the invasion of xerarch halophytes and its effects on the original reed community in the wetland after artificial drainage. The results showed that in the test reclaimed tidal wetland area, the xerarch halophyte community with Tripolium vulgare as edificator was spreading from northeast to southwest at a high speed of 143 m per year, with the original reed patch reduced and broken sharply, causing a 22.7 times increase in patch density index and a 1.3 times increase in shape index. After the growth seasons in 2006 and 2007, the biomass of T. vulgare in the plant community reached as high as 2783.8 g x m(-2), occupying 98% of the total, and the importance value reached 88%. At the mean time, the biomass and importance value of original reed decreased 98% and 83%, respectively. The invasion process of xerarch halophytes was meaningfully correlated with the moisture content and salinity in 0-20 cm soil layer. To effectively control the rapid invasion of xerarch halophytes, the mechanisms of their invasion and the strategies of rational and dynamic drainage management should be deeply studied. PMID:19449562

Gong, Jin-nan; Wang, Kai-yun; Zhang, Chao; Ma, Yong-liang

2009-01-01

65

Applying the species concept to plant viruses  

Microsoft Academic Search

Summary Plant virologists who maintain that the concept of species cannot be applied to viruses argue their case in terms of an obsolete concept of biological species defined by gene pools and reproductive isolation and applicable only to sexually reproducing organisms. In fact, various species concepts have been used by biologists and some of them are applicable to asexual organisms.

M. H. V. Van Regenmortel

1989-01-01

66

Exotic plant species invade hot spots of native plant diversity  

USGS Publications Warehouse

Some theories and experimental studies suggest that areas of low plant species richness may be invaded more easily than areas of high plant species richness. We gathered nested-scale vegetation data on plant species richness, foliar cover, and frequency from 200 1-m2 subplots (20 1000-m2 modified-Whittaker plots) in the Colorado Rockies (USA), and 160 1-m2 subplots (16 1000-m2 plots) in the Central Grasslands in Colorado, Wyoming, South Dakota, and Minnesota (USA) to test the generality of this paradigm. At the 1-m2 scale, the paradigm was supported in four prairie types in the Central Grasslands, where exotic species richness declined with increasing plant species richness and cover. At the 1-m2 scale, five forest and meadow vegetation types in the Colorado Rockies contradicted the paradigm; exotic species richness increased with native-plant species richness and foliar cover. At the 1000-m2 plot scale (among vegetation types), 83% of the variance in exotic species richness in the Central Grasslands was explained by the total percentage of nitrogen in the soil and the cover of native plant species. In the Colorado Rockies, 69% of the variance in exotic species richness in 1000-m2 plots was explained by the number of native plant species and the total percentage of soil carbon. At landscape and biome scales, exotic species primarily invaded areas of high species richness in the four Central Grasslands sites and in the five Colorado Rockies vegetation types. For the nine vegetation types in both biomes, exotic species cover was positively correlated with mean foliar cover, mean soil percentage N, and the total number of exotic species. These patterns of invasibility depend on spatial scale, biome and vegetation type, spatial autocorrelation effects, availability of resources, and species-specific responses to grazing and other disturbances. We conclude that: (1) sites high in herbaceous foliar cover and soil fertility, and hot spots of plant diversity (and biodiversity), are invasible in many landscapes; and (2) this pattern may be more closely related to the degree resources are available in native plant communities, independent of species richness. Exotic plant invasions in rare habitats and distinctive plant communities pose a significant challenge to land managers and conservation biologists.

Stohlgren, T. J.; Binkley, D.; Chong, G. W.; Kalkhan, M. A.; Schell, L. D.; Bull, K. A.; Otsuki, Y.; Newman, G.; Bashkin, M.; Yowhan, S.

1999-01-01

67

Exotic Plant Species Invade Hot Spots of Native Plant Diversity  

Microsoft Academic Search

Some theories and experimental studies suggest that areas of low plant spe- cies richness may be invaded more easily than areas of high plant species richness. We gathered nested-scale vegetation data on plant species richness, foliar cover, and frequency from 200 1-m2 subplots (20 1000-m2 modified-Whittaker plots) in the Colorado Rockies (USA), and 160 1-m2 subplots (16 1000-m2 plots) in

Thomas J. Stohlgren; Dan Binkley; Geneva W. Chong; Mohammed A. Kalkhan; Lisa D. Schell; Kelly A. Bull; Yuka Otsuki; Gregory Newman; Michael Bashkin; Yowhan Son

1999-01-01

68

SENSITVE PLANT SPECIES AND NOXIOUS WEED ASSESSMENT  

E-print Network

This report summarizes vegetation survey results for the proposed Boulder Bay Resort in Crystal Bay, Lake Tahoe, Nevada. The proposed project is located on private land, including the existing Tahoe Biltmore and the old Tahoe Mariner site. The survey addressed special interest, proposed, endangered, threatened, and sensitive plant species as well as noxious and invasive species.

unknown authors

2009-01-01

69

Salt tolerance in the halophyte Suaeda maritima L. Dum. : The maintenance of turgor pressure and water-potential gradients in plants growing at different salinities.  

PubMed

Osmotic potentials and individual epidermal cell turgor pressures were measured in the leaves of seedlings of Suaeda maritima growing over a range of salinities. Leaf osmotic potentials were lower (more negative) the higher the salt concentration of the solution and were lowest in the youngest leaves and stem apices, producing a gradient of osmotic potential towards the apex of the plant. Epidermal cell turgor pressures were of the order of 0.25 to 0.3 MPa in the youngest leaves measured, decreasing to under 0.05 MPa for the oldest leaves. This pattern of turgor pressure was largely unaffected by external salinity. Calculation of leaf water potential indicated that the gradient between young leaves and the external medium was not altered by salinity, but with older leaves, however, this gradient diminished from being the same as that for young leaves in the absence of NaCl, to under 30% of this value at 400 mM NaCl. These results are discussed in relation to the growth response of S. maritima. PMID:24241145

Clipson, N J; Tomos, A D; Flowers, T J; Jones, R G

1985-08-01

70

Reactive Oxygen Species in Plant Cell Walls  

Microsoft Academic Search

Plant cell walls are dynamic structures composed of polysaccharides, phenolics, and proteins. The plant cell wall is important\\u000a not only for maintaining cell shape, but it also responds to endogenous and environmental clues through the release of signaling\\u000a molecules, such as H2O2, which may act following autocrine and paracrine pathways. However, the primary function of reactive oxygen species (ROS)\\u000a production

Alfonso Ros Barceló; V. Gómez Ros Laura

71

American Journal of Plant Sciences, 2011, 2, 808-815 doi:10.4236/ajps.2011.26095 Published Online December 2011 (http://www.SciRP.org/journal/ajps)  

E-print Network

of Tamarix ramosissima to Extreme NaCl Concentrations Jacob M. Carter1,2* , Jesse B. Nippert1,3 1 Division of an introduced halophytic species, Tamarix ramosissima (Ledeb.). The physiological responses of Tamarix measured several whole plant and leaf-level physiological responses of Tamarix ramosissima cuttings grown

Nippert, Jesse

72

Methane dynamics across wetland plant species  

Microsoft Academic Search

We examined patterns of methane flux, plant biomass, and microbial methanogenic populations in nine wetland plant species. Methane dynamics varied across plant functional groupings, with patterns distinctive among forbs, clonal dominants, and tussock\\/clump-forming graminoids. Carex stricta and Scirpus atrovirens showed the highest emissions (31.7 and 20.6mgCH4-Cm?2h?1), followed by other tussock- or clump-forming graminoids that averaged 11.0mgCH4-Cm?2h?1 (Scirpus cyperinus, Glyceria striata,

Jenny Kao-Kniffin; Dominique S. Freyre; Teri C. Balser

2010-01-01

73

Effects of salinity on flowering, morphology, biomass accumulation and leaf metabolites in an edible halophyte.  

PubMed

The fresh water shortage in agriculture is an increasing problem worldwide, therefore the possibility of cultivating crops under saline conditions is of high importance. Crithmum maritimum, a halophytic plant naturally found on the rocky coastlines of the Atlantic Ocean and the Mediterranean Sea, has a long history of human consumption and was recently suggested as a cash crop for biosaline agriculture. In the present study, we compared the responses of different genotypes originating from France, Portugal and Israel to moderate saline irrigation (up to 100 mM NaCl). The genotypes varied greatly in the onset of flowering, their leaf appearance, growth habits and leaf metabolite content. Both Atlantic genotypes (from France and Portugal) flowered earlier than those from the Mediterranean, but the number of inflorescences decreased with salinity. Irrigation with 50 and 100 mM NaCl led to a reduction in biomass production in both the Israeli and the Portuguese genotypes, while the French genotype was found to produce maximum leaf yield at 50 mM NaCl. With increasing salinity, salt was accumulated by the plants, as indicated by increasing electrical conductivities of the leaf extracts. Concomitantly, antioxidant compounds (such as ascorbic acid), total polyphenols and ureides responded to salinity in a genotype-dependent manner; either they increased, decreased or were unaffected. Notably, the total fatty acid concentration increased with salinity in both Mediterranean genotypes, reaching 2.7 and 2.4 % total fatty acids (on a dry weight basis) at 100 mM NaCl. Moreover, the proportion assigned to omega-3 fatty acids in these genotypes was higher than in their Atlantic counterparts at the highest salinity tested. Our results highlight the variations existing among C. maritimum genotypes from different origins regarding salt-induced changes in plant growth, flowering behaviour and leaf metabolites with nutritional value. Thus, genotypic characteristics should be taken into account when evaluating a wild plant species for future crop cultivation. PMID:25178274

Ventura, Yvonne; Myrzabayeva, Malika; Alikulov, Zerekbay; Omarov, Rustem; Khozin-Goldberg, Inna; Sagi, Moshe

2014-01-01

74

Effects of salinity on flowering, morphology, biomass accumulation and leaf metabolites in an edible halophyte  

PubMed Central

The fresh water shortage in agriculture is an increasing problem worldwide, therefore the possibility of cultivating crops under saline conditions is of high importance. Crithmum maritimum, a halophytic plant naturally found on the rocky coastlines of the Atlantic Ocean and the Mediterranean Sea, has a long history of human consumption and was recently suggested as a cash crop for biosaline agriculture. In the present study, we compared the responses of different genotypes originating from France, Portugal and Israel to moderate saline irrigation (up to 100 mM NaCl). The genotypes varied greatly in the onset of flowering, their leaf appearance, growth habits and leaf metabolite content. Both Atlantic genotypes (from France and Portugal) flowered earlier than those from the Mediterranean, but the number of inflorescences decreased with salinity. Irrigation with 50 and 100 mM NaCl led to a reduction in biomass production in both the Israeli and the Portuguese genotypes, while the French genotype was found to produce maximum leaf yield at 50 mM NaCl. With increasing salinity, salt was accumulated by the plants, as indicated by increasing electrical conductivities of the leaf extracts. Concomitantly, antioxidant compounds (such as ascorbic acid), total polyphenols and ureides responded to salinity in a genotype-dependent manner; either they increased, decreased or were unaffected. Notably, the total fatty acid concentration increased with salinity in both Mediterranean genotypes, reaching 2.7 and 2.4 % total fatty acids (on a dry weight basis) at 100 mM NaCl. Moreover, the proportion assigned to omega-3 fatty acids in these genotypes was higher than in their Atlantic counterparts at the highest salinity tested. Our results highlight the variations existing among C. maritimum genotypes from different origins regarding salt-induced changes in plant growth, flowering behaviour and leaf metabolites with nutritional value. Thus, genotypic characteristics should be taken into account when evaluating a wild plant species for future crop cultivation. PMID:25178274

Ventura, Yvonne; Myrzabayeva, Malika; Alikulov, Zerekbay; Omarov, Rustem; Khozin-Goldberg, Inna; Sagi, Moshe

2014-01-01

75

Isolation, identification and expression analysis of salt-induced genes in Suaeda maritima, a natural halophyte, using PCR-based suppression subtractive hybridization  

PubMed Central

Background Despite wealth of information generated on salt tolerance mechanism, its basics still remain elusive. Thus, there is a need of continued effort to understand the salt tolerance mechanism using suitable biotechnological techniques and test plants (species) to enable development of salt tolerant cultivars of interest. Therefore, the present study was undertaken to generate information on salt stress responsive genes in a natural halophyte, Suaeda maritima, using PCR-based suppression subtractive hybridization (PCR-SSH) technique. Results Forward and reverse SSH cDNA libraries were constructed after exposing the young plants to 425 mM NaCl for 24 h. From the forward SSH cDNA library, 429 high quality ESTs were obtained. BLASTX search and TIGR assembler programme revealed overexpression of 167 unigenes comprising 89 singletons and 78 contigs with ESTs redundancy of 81.8%. Among the unigenes, 32.5% were found to be of special interest, indicating novel function of these genes with regard to salt tolerance. Literature search for the known unigenes revealed that only 17 of them were salt-inducible. A comparative analysis of the existing SSH cDNA libraries for NaCl stress in plants showed that only a few overexpressing unigenes were common in them. Moreover, the present study also showed increased expression of phosphoethanolamine N-methyltransferase gene, indicating the possible accumulation of a much studied osmoticum, glycinebetaine, in halophyte under salt stress. Functional categorization of the proteins as per the Munich database in general revealed that salt tolerance could be largely determined by the proteins involved in transcription, signal transduction, protein activity regulation and cell differentiation and organogenesis. Conclusion The study provided a clear indication of possible vital role of glycinebetaine in the salt tolerance process in S. maritima. However, the salt-induced expression of a large number of genes involved in a wide range of cellular functions was indicative of highly complex nature of the process as such. Most of the salt inducible genes, nonetheless, appeared to be species-specific. In light of the observations made, it is reasonable to emphasize that a comparative analysis of ESTs from SSH cDNA libraries generated systematically for a few halophytes with varying salt exposure time may clearly identify the key salt tolerance determinant genes to a minimum number, highly desirable for any genetic manipulation adventure. PMID:19497134

Sahu, Binod B; Shaw, Birendra P

2009-01-01

76

Physiological responses of a halophytic shrub to salt stress by Na2SO4 and NaCl: oxidative damage and the role of polyphenols in antioxidant protection.  

PubMed

Salt stress conditions lead to increased production of reactive oxygen species (ROS) in plant cells. Halophytes have the ability to reduce these toxic ROS by means of a powerful antioxidant system that includes enzymatic and non-enzymatic components. In this research, we used the halophytic shrub Prosopis strombulifera to investigate whether the ability of this species to grow under increasing salt concentrations and mixtures was related to the synthesis of polyphenolic compounds and to the maintenance of leaf pigment contents for an adequate photosynthetic activity. Seedlings of P. strombulifera were grown hydroponically in Hoagland's solution, gradually adding Na2SO4 and NaCl separately or in mixtures until reaching final osmotic potentials of -1, -1.9 and -2.6 MPa. Control plants were allowed to develop in Hoagland's solution without salt. Oxidative damage in tissues was determined by H2O2 and malondialdehyde content. Leaf pigment analysis was performed by high-performance liquid chromatography with ultraviolet, and total phenols, total flavonoids, total flavan-3-ols, condensed tannins, tartaric acid esters and flavonols were spectrophotometrically assayed. Treatment with Na2SO4 increased H2O2 production and lipid peroxidation in tissues and induced a sharp increase in flavonoid compounds (mainly flavan-3-ols) and consequently in the antioxidant activity. Also, Na2SO4 treatment induced an increased carotenoid/chlorophyll ratio, which may represent a strategy to protect photosystems against photooxidation. NaCl treatment, however, did not affect H2O2 content, lipid peroxidation, pigments or polyphenols synthesis. The significant accumulation of flavonoids in tissues under Na2SO4 treatment and their powerful antioxidant activity indicates a role for these compounds in counteracting the oxidative damage induced by severe salt stress, particularly, ionic stress. We demonstrate that ionic interactions between different salts in salinized soils modify the biochemical and morpho-physiological responses of P. strombulifera plants to salinity. PMID:25063834

Reginato, Mariana A; Castagna, Antonella; Furlán, Ana; Castro, Stella; Ranieri, Annamaria; Luna, Virginia

2014-01-01

77

Physiological responses of a halophytic shrub to salt stress by Na2SO4 and NaCl: oxidative damage and the role of polyphenols in antioxidant protection  

PubMed Central

Salt stress conditions lead to increased production of reactive oxygen species (ROS) in plant cells. Halophytes have the ability to reduce these toxic ROS by means of a powerful antioxidant system that includes enzymatic and non-enzymatic components. In this research, we used the halophytic shrub Prosopis strombulifera to investigate whether the ability of this species to grow under increasing salt concentrations and mixtures was related to the synthesis of polyphenolic compounds and to the maintenance of leaf pigment contents for an adequate photosynthetic activity. Seedlings of P. strombulifera were grown hydroponically in Hoagland's solution, gradually adding Na2SO4 and NaCl separately or in mixtures until reaching final osmotic potentials of ?1, ?1.9 and ?2.6 MPa. Control plants were allowed to develop in Hoagland's solution without salt. Oxidative damage in tissues was determined by H2O2 and malondialdehyde content. Leaf pigment analysis was performed by high-performance liquid chromatography with ultraviolet, and total phenols, total flavonoids, total flavan-3-ols, condensed tannins, tartaric acid esters and flavonols were spectrophotometrically assayed. Treatment with Na2SO4 increased H2O2 production and lipid peroxidation in tissues and induced a sharp increase in flavonoid compounds (mainly flavan-3-ols) and consequently in the antioxidant activity. Also, Na2SO4 treatment induced an increased carotenoid/chlorophyll ratio, which may represent a strategy to protect photosystems against photooxidation. NaCl treatment, however, did not affect H2O2 content, lipid peroxidation, pigments or polyphenols synthesis. The significant accumulation of flavonoids in tissues under Na2SO4 treatment and their powerful antioxidant activity indicates a role for these compounds in counteracting the oxidative damage induced by severe salt stress, particularly, ionic stress. We demonstrate that ionic interactions between different salts in salinized soils modify the biochemical and morpho-physiological responses of P. strombulifera plants to salinity. PMID:25063834

Reginato, Mariana A.; Castagna, Antonella; Furlán, Ana; Castro, Stella; Ranieri, Annamaria; Luna, Virginia

2014-01-01

78

Reduced Tonoplast Fast-Activating and Slow-Activating Channel Activity Is Essential for Conferring Salinity Tolerance in a Facultative Halophyte, Quinoa1[C][W][OA  

PubMed Central

Halophyte species implement a “salt-including” strategy, sequestering significant amounts of Na+ to cell vacuoles. This requires a reduction of passive Na+ leak from the vacuole. In this work, we used quinoa (Chenopodium quinoa) to investigate the ability of halophytes to regulate Na+-permeable slow-activating (SV) and fast-activating (FV) tonoplast channels, linking it with Na+ accumulation in mesophyll cells and salt bladders as well as leaf photosynthetic efficiency under salt stress. Our data indicate that young leaves rely on Na+ exclusion to salt bladders, whereas old ones, possessing far fewer salt bladders, depend almost exclusively on Na+ sequestration to mesophyll vacuoles. Moreover, although old leaves accumulate more Na+, this does not compromise their leaf photochemistry. FV and SV channels are slightly more permeable for K+ than for Na+, and vacuoles in young leaves express less FV current and with a density unchanged in plants subjected to high (400 mm NaCl) salinity. In old leaves, with an intrinsically lower density of the FV current, FV channel density decreases about 2-fold in plants grown under high salinity. In contrast, intrinsic activity of SV channels in vacuoles from young leaves is unchanged under salt stress. In vacuoles of old leaves, however, it is 2- and 7-fold lower in older compared with young leaves in control- and salt-grown plants, respectively. We conclude that the negative control of SV and FV tonoplast channel activity in old leaves reduces Na+ leak, thus enabling efficient sequestration of Na+ to their vacuoles. This enables optimal photosynthetic performance, conferring salinity tolerance in quinoa species. PMID:23624857

Bonales-Alatorre, Edgar; Shabala, Sergey; Chen, Zhong-Hua; Pottosin, Igor

2013-01-01

79

Learning from halophytes: physiological basis and strategies to improve abiotic stress tolerance in crops  

PubMed Central

Background Global annual losses in agricultural production from salt-affected land are in excess of US$12 billion and rising. At the same time, a significant amount of arable land is becoming lost to urban sprawl, forcing agricultural production into marginal areas. Consequently, there is a need for a major breakthrough in crop breeding for salinity tolerance. Given the limited range of genetic diversity in this trait within traditional crops, stress tolerance genes and mechanisms must be identified in extremophiles and then introduced into traditional crops. Scope and Conclusions This review argues that learning from halophytes may be a promising way of achieving this goal. The paper is focused around two central questions: what are the key physiological mechanisms conferring salinity tolerance in halophytes that can be introduced into non-halophyte crop species to improve their performance under saline conditions and what specific genes need to be targeted to achieve this goal? The specific traits that are discussed and advocated include: manipulation of trichome shape, size and density to enable their use for external Na+ sequestration; increasing the efficiency of internal Na+ sequestration in vacuoles by the orchestrated regulation of tonoplast NHX exchangers and slow and fast vacuolar channels, combined with greater cytosolic K+ retention; controlling stomata aperture and optimizing water use efficiency by reducing stomatal density; and efficient control of xylem ion loading, enabling rapid shoot osmotic adjustment while preventing prolonged Na+ transport to the shoot. PMID:24085482

Shabala, Sergey

2013-01-01

80

Structural and Functional State of Thylakoids in a Halophyte Suaeda altissima before and after Disturbance of Salt–Water Balance by Extremely High Concentrations of NaCl  

Microsoft Academic Search

Halophyte plants Suaeda altissima L. were grown in water culture at different concentrations of NaCl in the medium, and their leaves were sampled to examine the ultrastructure of chloroplasts. In parallel tests, the functional state of chloroplasts was assessed from parameters of chlorophyll fluorescence. In addition the effects of NaCl on plant growth and on the contents of Na+, K+,

Yu. V. Balnokin; E. B. Kurkova; N. A. Myasoedov; R. V. Lun'kov; N. Z. Shamsutdinov; E. A. Egorova; N. G. Bukhov

2004-01-01

81

Antioxidant enzyme activities and hormonal status in response to Cd stress in the wetland halophyte Kosteletzkya virginica under saline conditions.  

PubMed

Salt marshes constitute major sinks for heavy metal accumulation but the precise impact of salinity on heavy metal toxicity for halophyte plant species remains largely unknown. Young seedlings of Kosteletzkya virginica were exposed during 3 weeks in nutrient solution to Cd 5 µM in the presence or absence of 50 mM NaCl. Cadmium (Cd) reduced growth and shoot water content and had major detrimental effect on maximum quantum efficiency (F(v) /F(m) ), effective quantum yield of photosystem II (Y(II)) and electron transport rates (ETRs). Cd induced an oxidative stress in relation to an increase in O(2) (•-) and H(2) O(2) concentration and lead to a decrease in endogenous glutathione (GSH) and ?-tocopherol in the leaves. Cd not only increased leaf zeatin and zeatin riboside concentration but also increased the senescing compounds 1-aminocyclopropane-1-carboxylic acid (ACC) and abscisic acid (ABA). Salinity reduced Cd accumulation already after 1 week of stress but was unable to restore shoot growth and thus did not induce any dilution effect. Salinity delayed the Cd-induced leaf senescence: NaCl reduced the deleterious impact of Cd on photosynthesis apparatus through an improvement of F(v) /F(m) , Y(II) and ETR. Salt reduced oxidative stress in Cd-treated plants through an increase in GSH, ?-tocopherol and ascorbic acid synthesis and an increase in glutathione reductase (EC 1.6.4.2) activity. Additional salt reduced ACC and ABA accumulation in Cd+NaCl-treated leaves comparing to Cd alone. It is concluded that salinity affords efficient protection against Cd to the halophyte species K. virginica, in relation to an improved management of oxidative stress and hormonal status. PMID:22697433

Han, Rui-Ming; Lefèvre, Isabelle; Albacete, Alfonso; Pérez-Alfocea, Francisco; Barba-Espín, Gregorio; Díaz-Vivancos, Pedro; Quinet, Muriel; Ruan, Cheng-Jiang; Hernández, José Antonio; Cantero-Navarro, Elena; Lutts, Stanley

2013-03-01

82

Egyptian plant species as new ozone indicators.  

PubMed

The aim of this study was to test and select one or more highly sensitive, specific and environmentally successful Egyptian bioindicator plants for ozone (O3). For that purpose more than 30 Egyptian species and cultivars were subjected to extensive screening studies under controlled environmental and pollutant exposure conditions to mimic the Egyptian environmental conditions and O3 levels in urban and rural sites. Four plant species were found to be more sensitive to O3 than the universally used O3-bioindicator, tobacco Bel W3, under the Egyptian environmental conditions used. These plant species, jute (Corchorus olitorius c.v. local), clover (Trifolium alexandrinum L. c.v. Masry), garden rocket (Eruca sativa c.v. local) and alfalfa (Medicago sativa L. c.v. local), ranked in order of decreasing sensitivity, exhibited typical O3 injury symptoms faster and at lower 03 concentrations than Bel W3. Three variables were tested in search of a reliable tool for the diagnosis and prediction of O3 response prior to the appearance of visible foliar symptoms: pigment degradation, stomatal conductance (g(s)) and net photosynthetic CO2 assimilation (Pnet). Pigment degradation was found to be unreliable in predicting species sensitivity to O3. Evidence supporting stomatal conductance involvement in 03 tolerance was found only in tolerant species. A good correlation was found between g(s), restriction of O3 and CO2 influx into the mesophyll tissues, and Pnet. Changes in Pnet seemed to depend largely on fluctuations in g(s). PMID:12395848

Madkour, Samia A; Laurence, J A

2002-01-01

83

Plant species intermediate for c3, c4 photosynthesis.  

PubMed

Mollugo verticillata is the first plant species reported which has characteristics of both C(3) (Calvin-Benson pathway) and C(4) (Hatch-Slack pathway) plants. This plant species is intermediate between C(3) and C(4) plants in at least four features generally used to separate those two plant groups: leaf anatomy, cell ultrastructure, photorespiration, and primary photosynthetic products. PMID:17736195

Kennedy, R A; Laetsch, W M

1974-06-01

84

Plant Species Intermediate for C3, C4 Photosynthesis  

Microsoft Academic Search

Mollugo verticillata is the first plant species reported which has characteristics of both C3 (Calvin-Benson pathway) and C4 (Hatch-Slack pathway) plants. This plant species is intermediate between C3 and C4 plants in at least four features generally used to separate those two plant groups: leaf anatomy, cell ultrastructure, photorespiration, and primary photosynthetic products.

R. A. Kennedy; W. M. Laetsch

1974-01-01

85

THE INTRODUCTION OF POTENTIALLY INVASIVE ALIEN PLANT SPECIES FOR HORTICULTURAL  

E-print Network

THE INTRODUCTION OF POTENTIALLY INVASIVE ALIEN PLANT SPECIES FOR HORTICULTURAL PURPOSES IN NORTH: The Introduction of Potentially Invasive Alien Plant Species for Horticultural Purposes in North America: Assessing/Approved: ________________________________________ #12;iii ABSTRACT Invasive alien plant species are known to cause significant economic and ecological

86

Assessment of the potential of halophytes as energy crops for the electric utility industry. Final report  

SciTech Connect

This technical report assesses and estimates the potential of selected halophytes as future renewable energy resources, especially by US electric utilities, and familiarizes nonspecialists with research and development problems that must be resolved before these energy sources can become dependable supplies of energy. A literature search related to both indigenous and exotic species of halophytes has been done and appropriate terrestrial species have been selected. Selection criteria include: total biomass potential, genetic constraints, establishment and cultivation requirements, regions of suitability, secondary credits, and a number of other factors. Based on these selection criteria, for the arid western states with high levels of salinity in water and/or soils, there is little potential for energy feedstocks derived from grasses and herbaceous forbs. Likewise, coastal marshes, estuaries, and mangrove swamps, although excellent biomass producers, are too limited by region and have too many ecological and environmental problems for consideration. The deep-rooted, perennial woody shrubs indigenous to many saline regions of the west provide the best potential. The number of species in this group is limited, and Atriplex canescens, Sarcobatus vermiculatus, and Chrysothamnus nauseosus are the three species with the greatest biological potential. These shrubs would receive minimal energy inputs in cultivation, would not compete with agricultural land, and would restore productivity to severely disturbed sites. One might logically expect to achieve biomass feedstock yields of three to five tons/acre/yr on a long-term sustainable basis. The possibility also exists that exotic species might be introduced. 67 references, 1 figure, 5 tables.

Goodin, J.R.

1984-09-01

87

A novel methyl transferase induced by osmotic stress in the facultative halophyte Mesembryanthemum crystallinum.  

PubMed Central

Molecular mechanisms of osmotic stress tolerance were studied in Mesembryanthemum crystallinum (ice plant), a facultative halophyte capable of adjusting to and surviving in highly saline conditions. We screened a subtracted cDNA library enriched for salt stress-induced mRNAs to identify transcripts involved in this plant's adaptation to salinity. One mRNA, Imt1, was found to be up-regulated in leaves and, transiently, in roots. Nuclear run-on assays indicated that this mRNA is transcriptionally regulated. Imt1 encoded a predicted polypeptide of M(r) 40,250 which exhibited sequence similarity to several hydroxymethyl transferases. Expression of the protein in Escherichia coli and subsequent activity assays identified the protein as a novel myoinositol O-methyl transferase which catalyzes the first step in the biosynthesis of the cyclic sugar alcohol pinitol. Pinitol accumulates in salt-stressed M.crystallinum and is abundant in a number of salt- and drought-tolerant plants. The presence of high levels of sugar alcohols correlates with osmotolerance in a diverse range of organisms, including bacteria, fungi and algae, as well as higher plants. The stress-initiated transcriptional induction of IMT1 expression in a facultative halophyte provides strong support for the importance of sugar alcohols in establishing tolerance to osmotic stress in higher plants. Images PMID:1600940

Vernon, D M; Bohnert, H J

1992-01-01

88

Interactions Among Grassland Plant Species, Microbial Communities, and Soil Processes  

Microsoft Academic Search

Plant-microbial interactions are thought to be an important determinant of ecosystem processes, yet we do not know whether impacts of plant species on soil microbial community composition translate to impacts on function. We established field plots in a California annual grassland of five plant monocultures for two years to determine the effects of different plant species on the composition of

V. Eviner; M. Waldrop; E. Schwartz; J. Pett-Ridge; M. Firestone

2002-01-01

89

Tolerance of combined submergence and salinity in the halophytic stem-succulent Tecticornia pergranulata  

Microsoft Academic Search

† Background and Aims Habitats occupied by many halophytes are not only saline, but are also prone to flooding. Few studies have evaluated submergence tolerance in halophytes. † Methods Responses to submergence, at a range of salinity levels, were studied for the halophytic stem-succulent Tecticornia pergranulata subsp. pergranulata (syn. Halosarcia pergranulata subsp. pergranulata). Growth and total sugars in succulent stems

T. D. Colmer; H. Vos; O. Pedersen

2009-01-01

90

Flavonoids from the halophyte Apocynum venetum and their antifouling activities against marine biofilm-derived bacteria.  

PubMed

Eleven flavonoids were isolated from the leaves of the halophyte Apocynum venetum. Among them, the isolation of plumbocatechin A (1), 8-O-methylretusin (2) and kaempferol 3-O-(6?-O-acetyl)-?-D-galactopyranoside (7) was reported for the first time from this plant. Their structures were identified by using spectral methods, including 2D NMR experiments, and confirmed by comparing with the literature data. In addition, the antifouling activities of these compounds against the marine fouling bacteria, Bacillus thuringiensis, Pseudoalteromonas elyakovii and Pseudomonas aeruginosa, have been evaluated in this article. PMID:24588258

Kong, Na-Na; Fang, Sheng-Tao; Liu, Ying; Wang, Jian-Hua; Yang, Cui-Yun; Xia, Chuan-Hai

2014-01-01

91

The effect of calcium on the antioxidant systems in the halophyte Cakile maritima under salt stress  

Microsoft Academic Search

The purpose of the current investigation was to study the effect of Ca2+ (0, 3.5 and 20 mM concentrations) on the antioxidant systems in the halophyte Cakile maritima under NaCl stress (0, 100, 200 and 400 mM NaCl). Plants treated with both moderate calcium (3.5 mM) and salt levels (100 mM)\\u000a showed the maximum growth, and the addition of 20 mM calcium to the nutrient

Nader Ben Amor; Wided Megdiche; Ana Jiménez; Francisca Sevilla; Chedly Abdelly

2010-01-01

92

Effects of Salinity on the Response of the Wetland Halophyte Kosteletzkya virginica (L.) Presl. to Copper Toxicity  

Microsoft Academic Search

Kosteletzkya virginica (L.) Presl. is a perennial wetland halophyte which could be exposed to heavy metals in polluted salt marsh environments.\\u000a In order to investigate the interaction between salinity (50 mM NaCl) and heavy metal, young plants were exposed in hydroponic\\u000a culture to 10 ?M Cu in the presence or absence of 50 mM NaCl. Copper strongly inhibited the leaf emergence and lateral

Rui-Ming Han; Isabelle Lefèvre; Cheng-Jiang Ruan; Natacha Beukelaers; Pei Qin; Stanley Lutts

93

Interactive effects of various salt and alkali stresses on growth, organic solutes, and cation accumulation in a halophyte Spartina alterniflora (Poaceae)  

Microsoft Academic Search

Soil salinization and alkalinization frequently co-occur in nature, but very few studies focus on the interactive effects of various salt and alkali stresses on plants. A study quantifying the effects of various salt and alkali stresses on growth, organic solutes, and cation accumulation in a halophyte Spartina alterniflora was conducted. The experiment consisted of six levels of salinity (100, 200,

R. Li; F. Shi; K. Fukuda

2010-01-01

94

Northeast Wetland Flora: Field Office Guide to Plant Species  

NSDL National Science Digital Library

The USDA Natural Resource Conservation Service's Northeast National Technical Center in Chester, Pennsylvania produced Northeast Wetland Flora: Field Office Guide to Plant Species. The guide contains black and white illustrations, full species descriptions (with color photographs, illustrations, and small distribution maps), illustrated glossaries, an alphabetical species list (provides common and scientific names for 300 species of vascular plants), and a key to generalized plant groups. The guide may be browsed online or downloaded in .zip format.

95

Southern Wetland Flora: Field Office Guide to Plant Species  

NSDL National Science Digital Library

The US Department of Agriculture's (USDA) Soil Conservation Service branch in Fort Worth, Texas produced the Southern Wetland Flora: Field Office Guide to Plant Species. The guide contains black and white illustrations, full species descriptions (with color photographs, illustrations, and small distribution maps), illustrated glossaries, an alphabetical species list (provides common and scientific names for 300 species of vascular plants), and a key to generalized plant groups. The guide may be browsed online or downloaded in .zip format.

2007-11-15

96

Exotic plant species in the southern boreal forest of Saskatchewan  

Microsoft Academic Search

Exotic species possess abilities to harm the ecosystems they invade. This study assesses the density, frequency and cover of exotic plants in roadside right-of-ways, logged areas and wildfire sites within mixedwood sections of the southern boreal forest of Saskatchewan. A total of 23 exotic species were observed including nine species of Gramineae, seven species of Leguminosae and five species of

W. H. Sumners; O. W. Archibold

2007-01-01

97

Dioxin uptake by Indian plant species.  

PubMed

Dioxins like various gaseous pollutants and aerosols can be scavenged by appropriate vegetative greenbelts. Based on their stomatal properties and the models for contaminant uptake, uptake of dioxin (2,3,7,8-TCDD) by three important Indian plant species, viz. Eugenia jambolana (Jamun), Azadirachta indica (Neem) and Ficus religiosa (Peepal), has been estimated. 2,3,7,8-TCDD is a contaminant with severe harmful ecological ramifications. Computations show that Ficus religiosa has highest uptake capacity. The present exercise has its utility in designing appropriate green-belts for mitigating adverse environmental and human health impacts due to dioxins. This can be an effective management option for mitigating the damages caused by dioxins. PMID:17874332

Pandey, J S; Kumar, R; Wate, S R

2008-08-01

98

New pasture plants intensify invasive species risk.  

PubMed

Agricultural intensification is critical to meet global food demand, but intensification threatens native species and degrades ecosystems. Sustainable intensification (SI) is heralded as a new approach for enabling growth in agriculture while minimizing environmental impacts. However, the SI literature has overlooked a major environmental risk. Using data from eight countries on six continents, we show that few governments regulate conventionally bred pasture taxa to limit threats to natural areas, even though most agribusinesses promote taxa with substantial weed risk. New pasture taxa (including species, subspecies, varieties, cultivars, and plant-endophyte combinations) are bred with characteristics typical of invasive species and environmental weeds. By introducing novel genetic and endophyte variation, pasture taxa are imbued with additional capacity for invasion and environmental impact. New strategies to prevent future problems are urgently needed. We highlight opportunities for researchers, agribusiness, and consumers to reduce environmental risks associated with new pasture taxa. We also emphasize four main approaches that governments could consider as they build new policies to limit weed risks, including (i) national lists of taxa that are prohibited based on environmental risk; (ii) a weed risk assessment for all new taxa; (iii) a program to rapidly detect and control new taxa that invade natural areas; and (iv) the polluter-pays principle, so that if a taxon becomes an environmental weed, industry pays for its management. There is mounting pressure to increase livestock production. With foresight and planning, growth in agriculture can be achieved sustainably provided that the scope of SI expands to encompass environmental weed risks. PMID:25368175

Driscoll, Don A; Catford, Jane A; Barney, Jacob N; Hulme, Philip E; Inderjit; Martin, Tara G; Pauchard, Aníbal; Pyšek, Petr; Richardson, David M; Riley, Sophie; Visser, Vernon

2014-11-18

99

Endothall Species Selectivity Evaluation: Southern Latitude Aquatic Plant Community  

Microsoft Academic Search

Species selectivity of the aquatic herbicide endothall as the formulation Aquathol® K was evaluated on a variety of plant species commonly found in southern latitude United States aquatic plant communities. Submersed species includ- ed hydrilla ( Hydrilla verticillata (L.f.) Royle.), wild celery ( Val- lisneria americana L.), American pondweed ( Potamogeton nodosus Poiret), southern naiad ( Najas guadalupensis (Spren- gel)

JOHN G. SKOGERBOE; KURT D. GETSINGER

100

Tennessee plant species screened for renewable energy sources  

Microsoft Academic Search

The USDA Northern Regional Research Center (NRRC) has previously studied chemical and botanical characteristics of about 1000 plant species in efforts to identify potential new plant sources for industrial raw materials. For this report, an additional 51 species were collected from Tennessee and studied. Above-ground plant samples were analyzed for yields of oils, polyphenols, hydrocarbons, protein, and ash. Oils were

M. E. Carr; M. O. Bagby

2009-01-01

101

Plant Species Recovery on a Compacted Skid Road  

PubMed Central

This study was executed to determine the plant species of herbaceous cover in a skid road subjected to soil compaction due to timber skidding in a beech (Fagus orientalis Lipsky.) stand. Our previous studies have shown that ground based timber skidding destroys the soils extremely, and degradations on ecosystem because of the timber skidding limit recovery and growth of plant cover on skid roads. However, some plant species show healthy habitat, recovery and they can survive after the extreme degradation in study area. We evaluated composition of these plant species and their cover-abundance scales in 100 m x 3 m transect. 15 plant species were determined belongs to 12 plant families and Liliaceae was the highest representative plant family. Smilax aspera L., Epimedium pubigerum (DC.) Moren et Decaisne, Carex distachya Desf. var. distachya Desf., Pteridium aquilinum (L.) Kuhn., Trachystemon orientalis (L.) G. Don, Hedera helix L. have the highest cover-abundance scale overall of determined species on compacted skid road.

Demir, Murat; Makineci, Ender; Gungor, Beyza Sat

2008-01-01

102

Factors influencing levels of genetic diversity in woody plant species  

Microsoft Academic Search

The plant allozyme literature was reviewed to: (1) compare genetic diversity in long-lived woody species with species representing other life forms, and (2) to investigate whether the levels and distribution of genetic diversity in woody species are related to life history and ecological characteristics. Data from 322 woody taxa were used to measure genetic diversity within species, and within and

J. L. Hamrick; Mary Jo W. Godt; Susan L. Sherman-Broyles

1992-01-01

103

Final Report Parris Island Depot Invasive Plant Species  

E-print Network

Final Report Parris Island Depot Invasive Plant Species Control Monitoring December 2010 Submitted Species Occurrence and Management Page 6 a. Invasive Species Survey Conducted in 2001 Page 7 b. Management and Control Efforts Page 9 c. Herbicides Page 10 IV. 2010 Survey of Invasive Species Page 16 a. Survey Methods

Bolding, M. Chad

104

High apoplastic solute concentrations in leaves alter water relations of the halophytic shrub, Sarcobatus vermiculatus.  

PubMed

Predawn plant water potential (Psi(w)) is used to estimate soil moisture available to plants because plants are expected to equilibrate with the root-zone Psi(w). Although this equilibrium assumption provides the basis for interpreting many physiological and ecological parameters, much work suggests predawn plant Psi(w) is often more negative than root-zone soil Psi(w). For many halophytes even when soils are well-watered and night-time shoot and root water loss eliminated, predawn disequilibrium (PDD) between leaf and soil Psi(w) can exceed 0.5 MPa. A model halophyte, Sarcobatus vermiculatus, was used to test the predictions that low predawn solute potential (Psi(s)) in the leaf apoplast is a major mechanism driving PDD and that low Psi(s) is due to high Na+ and K+ concentrations in the leaf apoplast. Measurements of leaf cell turgor (Psi(p)) and solute potential (Psi(s)) of plants grown under a range of soil salinities demonstrated that predawn symplast Psi(w) was 1.7 to 2.1 MPa more negative than predawn xylem Psi(w), indicating a significant negative apoplastic Psi(s). Measurements on isolated apoplastic fluid indicated that Na+ concentrations in the leaf apoplast ranged from 80 to 230 mM, depending on salinity, while apoplastic K+ remained around 50 mM. The water relations measurements suggest that without a low apoplastic Psi(s), predawn Psi(p) may reach pressures that could cause cell damage. It is proposed that low predawn apoplastic Psi(s) may be an efficient way to regulate Psi(p) in plants that accumulate high concentrations of osmotica or when plants are subject to fluctuating patterns of soil water availability. PMID:16317037

James, J J; Alder, N N; Mühling, K H; Läuchli, A E; Shackel, K A; Donovan, L A; Richards, J H

2006-01-01

105

Quantitation and Purification of Quaternary Ammonium Compounds From Halophyte Tissue  

PubMed Central

A simple and sensitive spectrophotometric assay for quaternary ammonium compounds (QACs) based on Dragendorff's reagent is described. Although not specific for a particular QAC, the assay allows for rapid survey of tissue for QAC content. A separation method for QACs in halophyte tissue containing high levels of cations was developed using ion exchange resins and ninhydrin to remove the amino acid fraction. PMID:16663593

Stumpf, David K.

1984-01-01

106

Sagina maritima Don (Caryophyllaceae) and other halophytes in London  

Microsoft Academic Search

Sagina maritima has been recorded at three sites by the River Thames near central London, much further from the open sea than elsewhere in Britain. Other halophytes occur nearby. Hydrological data and other records suggest that saline water carrying seeds or other propagules penetrated far upstream during periods of unusually low freshwater river flow. These are the first records of

J. A. EDGINGTON

107

Plant species effects on soil nematode communities in experimental grasslands  

Microsoft Academic Search

We examined the effects of 12 different plant species on soil nematode abundance and community composition, and rotifer abundance, in an experimental grassland in Northern Sweden. Monocultures were grown for six or seven growing seasons before sampling. Four monocultures were grasses, four were legumes and four were non-leguminous forbs. Plant species identity had an effect on the nematode community, both

Maria Viketoft; Cecilia Palmborg; Björn Sohlenius; Kerstin Huss-Danell; Jan Bengtsson

2005-01-01

108

RARE PLANT SPECIES IN MASSACHUSETTS KATIIARINI; G. FIELD  

E-print Network

1 II RARE PLANT SPECIES IN MASSACHUSETTS KATIIARINI; G. FIELD 1 AND JONATHAN CODPINGTON 242 vascular plant species were listed as rare tn Massachusetts (Coddington & Field, 1978). There are several the list obsolete. In Massachusetts, all of these problems obtain. Nevertheless, cer- tain patterns

Mathis, Wayne N.

109

Global response patterns of terrestrial plant species to nitrogen addition  

Microsoft Academic Search

Summary • Better understanding of the responses of terrestrial plant species under global nitrogen (N) enrichment is critical for projection of changes in structure, functioning, and service of terrestrial ecosystems.  Here, a meta-analysis of data from 304 studies was carried out to reveal the general response patterns of terrestrial plant species to the addition of N.  Across 456

Jianyang Xia; Shiqiang Wan

2008-01-01

110

Plant species loss decreases arthropod diversity and shifts trophic structure  

E-print Network

LETTER Plant species loss decreases arthropod diversity and shifts trophic structure Nick M. Haddad results for each hypothesis. We sampled arthropods for over a decade in an experiment that manipulated- to high-plant species richness, in abundances of predatory and parasitoid arthropods relative

Haddad, Nick

111

Determinants of plant species richness on small Bahamian islands  

E-print Network

Determinants of plant species richness on small Bahamian islands Lloyd W. Morrison* School of island location in relation to neighbouring landmasses on plant species richness and the predictive ability of regression models. Location Archipelagos of small islands in the central Exumas and near

Morrison, Lloyd W.

112

Ragworm fatty acid profiles reveals habitat and trophic interactions with halophytes and with mercury.  

PubMed

The present study aimed to assess if ragworm fatty acids (FA) profiles could be used to discriminate their spatial distribution in an historically mercury-contaminated estuarine environment, i.e., if it was possible to differentiate ragworms present in salt marsh sediments surrounding plant roots and rhizomes (rhizosediment) from adjacent unvegetated sediment. Additionally, we also tried to determine if ragworms differed in mercury content and if these values could also be used to identify the habitat they occur in. Results show that, within the same area, ragworms can be distinguished using FA profiles and that in halophyte rhizosediment ragworms display more than twice the levels of alpha-linolenic acid (18:3n-3). The ratio cis-vaccenic/oleic acids (18:1n-7/18:ln-9) in ragworms suggests higher carnivory in unvegetated sediments. Our study indicates that ragworm FA profiles can be used to identify their habitat, their trophic interaction with halophytes and reveal a spatially contrasting feeding behaviour, which also reflects mercury accumulation. PMID:22944176

Lillebø, Ana Isabel; Cleary, Daniel Francis Richard; Marques, Bruna; Reis, Alberto; Lopes da Silva, Teresa; Calado, Ricardo

2012-11-01

113

Phylogeographic patterns of highland and lowland plant species in Japan  

Microsoft Academic Search

As a result of ecological and historical factors, plant species occurring in mountainous regions often exhibit complex phylogeographical\\u000a structure. The aim of this review is to identify the main phylogeographic patterns of plant species in the Japanese Archipelago,\\u000a based on 63 previous studies; in particular, the intention is to examine the effects of mountains on these patterns. We classified\\u000a species

Takafumi Ohsawa; Yuji Ide

2011-01-01

114

Tennessee plant species screened for renewable energy sources  

Microsoft Academic Search

The USDA Northern Regional Research Center (NRRC) has previously studied chemical and botanical characteristics of about 1,000\\u000a plant species in efforts to identify potential new plant sources for industrial raw materials. For this report, an additional\\u000a 51 species were collected from Tennessee and studied. Above-ground plant samples were analyzed for yields of oils, polyphenols,\\u000a hydrocarbons, protein, and ash. Oils were

M. E. Carr; M. O. Bagby

1987-01-01

115

EVOLUTIONARY CHANGE IN THREE SPECIES OF COMMON ROADSIDE PLANTS  

Microsoft Academic Search

Roadsides are an interesting and unusual habitat. Plants inhabiting these degraded areas are exposed to many easily identifiable and unnatural selection pressures. In this thesis, I examine the evolutionary ecology of three species (Dipsacus sylvestris, Hesperis matronalis and Asclepias syriaca) of common roadside plants. I collected seeds from several maternal plants from three oldfield and three roadside populations. In all

LAURA LOUISE BEATON

2004-01-01

116

Over expression of cytosolic copper\\/zinc superoxide dismutase from a mangrove plant Avicennia marina in indica Rice var Pusa Basmati1 confers abiotic stress tolerance  

Microsoft Academic Search

Antioxidant enzymes play an important role in conferring abiotic stress tolerance. Superoxide dismutase (SOD) is the first\\u000a enzyme in the enzymatic antioxidative pathway. Halophytic plants like mangroves have been reported to have a high level of\\u000a SOD activity, which plays a major role in defending the mangrove species against severe abiotic stresses. We had previously\\u000a reported the isolation of Sod1,

S. R. Prashanth; V. Sadhasivam; Ajay Parida

2008-01-01

117

Differences in proton pumping and Na/H exchange at the leaf cell tonoplast between a halophyte and a glycophyte  

PubMed Central

The tonoplast Na+/H+ antiporter and tonoplast H+ pumps are essential components of salt tolerance in plants. The objective of this study was to investigate the transport activity of the tonoplast Na+/H+ antiporter and the tonoplast V-H+-ATPase and V-H+-PPase in a highly tolerant salt-accumulating halophyte, Salicornia dolichostachya, and to compare these transport activities with activities in the related glycophyte Spinacia oleracea. Vacuolar membrane vesicles were isolated by density gradient centrifugation, and the proton transport and hydrolytic activity of both H+ pumps were studied. Furthermore, the Na+/H+-exchange capacity of the vesicles was investigated by 9-amino-6-chloro-2-methoxyacridine fluorescence. Salt treatment induced V-H+-ATPase and V-H+-PPase activity in vesicles derived from S. oleracea, whereas V-H+-ATPase and V-H+-PPase activity in S. dolichostachya was not affected by salt treatment. Na+/H+-exchange capacity followed the same pattern, i.e. induced in response to salt treatment (0 and 200 mM NaCl) in S. oleracea and not influenced by salt treatment (10 and 200 mM NaCl) in S. dolichostachya. Our results suggest that S. dolichostachya already generates a high tonoplast H+ gradient at low external salinities, which is likely to contribute to the high cellular salt accumulation of this species at low external salinities. At high external salinities, S. dolichostachya showed improved growth compared with S. oleracea, but V-H+-ATPase, V-H+-PPase and Na+/H+-exchange activities were comparable between the species, which might imply that S. dolichostachya more efficiently retains Na+ in the vacuole. PMID:24887002

Katschnig, Diana; Jaarsma, Rinse; Almeida, Pedro; Rozema, Jelte; Schat, Henk

2014-01-01

118

Do alien plant invasions really affect pollination success in native plant species?  

Microsoft Academic Search

A growing number of studies on naturally occurring plant species have shown that plant-plant interactions for pollination vary from competitive to facilitative. In reviewing the seven published studies on how alien species can affect the pollination success in natives, we found that all authors suggest competitive effects to dominate, either through reduced pollinator visitation rates or through increased heterospecific pollination

Anne-Line Bjerknes; Ørjan Totland; Stein Joar Hegland; Anders Nielsen

2007-01-01

119

Alternate-Fueled Flight: Halophytes, Algae, Bio-, and Synthetic Fuels  

NASA Technical Reports Server (NTRS)

Synthetic and biomass fueling are now considered to be near-term aviation alternate fueling. The major impediment is a secure sustainable supply of these fuels at reasonable cost. However, biomass fueling raises major concerns related to uses of common food crops and grasses (some also called "weeds") for processing into aviation fuels. These issues are addressed, and then halophytes and algae are shown to be better suited as sources of aerospace fuels and transportation fueling in general. Some of the history related to alternate fuels use is provided as a guideline for current and planned alternate fuels testing (ground and flight) with emphasis on biofuel blends. It is also noted that lessons learned from terrestrial fueling are applicable to space missions. These materials represent an update and additions to the Workshop on Alternate Fueling Sustainable Supply and Halophyte Summit at Twinsburg, OH, Oct. 17 to 18, 2007 (ref. 1).

Hendricks, R. C.

2007-01-01

120

Alternate-Fueled Flight: Halophytes, Algae, Bio-, and Synthetic Fuels  

NASA Technical Reports Server (NTRS)

Synthetic and biomass fueling are now considered to be near-term aviation alternate fueling. The major impediment is a secure sustainable supply of these fuels at reasonable cost. However, biomass fueling raises major concerns related to uses of common food crops and grasses (some also called "weeds") for processing into aviation fuels. These issues are addressed, and then halophytes and algae are shown to be better suited as sources of aerospace fuels and transportation fueling in general. Some of the history related to alternate fuels use is provided as a guideline for current and planned alternate fuels testing (ground and flight) with emphasis on biofuel blends. It is also noted that lessons learned from terrestrial fueling are applicable to space missions. These materials represent an update (to 2009) and additions to the Workshop on Alternate Fueling Sustainable Supply and Halophyte Summit at Twinsburg, Ohio, October 17 to 18, 2007.

Hendricks, R. C.

2012-01-01

121

Trichoderma species — opportunistic, avirulent plant symbionts  

Microsoft Academic Search

Trichoderma spp. are free-living fungi that are common in soil and root ecosystems. Recent discoveries show that they are opportunistic, avirulent plant symbionts, as well as being parasites of other fungi. At least some strains establish robust and long-lasting colonizations of root surfaces and penetrate into the epidermis and a few cells below this level. They produce or release a

Charles R. Howell; Ada Viterbo; Ilan Chet; Matteo Lorito; Gary E. Harman

2004-01-01

122

Transmission specificities of plant viruses with the newly identified species of the Bemisia tabaci species complex.  

PubMed

Bemisia tabaci has had a colorful nomenclatural past and is now recognized as a species complex. This new species framework has added many new areas of research including adding new insight into the virus transmission specificity of the species in the B. tabaci species complex. There is a wide disparity in what is known about the transmission of plant viruses by different members of the B. tabaci species complex. In this paper, we have synthesized the transmission specificities of the plant viruses transmitted by species belonging to the complex. There are five genera of plant viruses with members that are transmitted by species of the B. tabaci species complex. The transmission of viruses belonging to two of these, Begomovirus and Crinivirus, are well studied and much is known in regards to the relationship between species and transmission and etiology. This is in contrast to viruses of the genera, Torradovirus and Carlavirus, for which very little is known inregards to their transmission. This is the first attempt to integrate viral data within the new B. tabaci species complex framework. It is clear that matching historical transmission data with the current species framework is difficult due to the lack of awareness of the underlying genetic diversity within B. tabaci. We encourage all researchers to determine which species of B. tabaci they are using to facilitate association of phenotypic traits with particular members of the complex. PMID:24464790

Polston, Jane E; De Barro, Paul; Boykin, Laura M

2014-10-01

123

Plant species richness in montane grasslands affects the fitness of a generalist grasshopper species.  

PubMed

Theory predicts negative effects of increasing plant diversity on the abundance of specialist insect herbivores, but little is known about how plant diversity affects the performance and abundance of generalist insect herbivores. We studied oviposition rates and offspring numbers in females of the generalist grasshopper Chorthippus parallelus that were collected in 15 montane grasslands in 2005 and 2007 along a gradient of plant species richness in central Germany. In addition to plant species richness, we determined evenness and plant community composition in the grasslands and measured aboveground plant biomass and other habitat variables such as leaf area index, vegetation height, and solar radiation. There was substantial variation among sites in grasshopper fecundity and the number of nymphs that hatched from the egg pods. Both fitness measures were positively influenced by plant species richness at the sites, while female fitness did not correlate with any of the other habitat parameters. Abundance of C. parallelus in the grasslands was positively correlated with plant species richness, plant community composition, and incident solar radiation of the sites. There were no phenological differences between grasshoppers from the different study sites. Our results suggest that decreasing biodiversity threatens the persistence not only of specialist, but also of generalist insect herbivores via a variety of mechanisms including a decrease in diversity of the generalists' food plants. PMID:20462122

Unsicker, Sybille B; Franzke, Alexandra; Specht, Juliane; Köhler, Günter; Linz, Jeanine; Renker, Carsten; Stein, Claudia; Weisser, Wolfgang W

2010-04-01

124

Plant species differences in particulate matter accumulation on leaf surfaces.  

PubMed

Particulate matter (PM) accumulation on leaves of 22 trees and 25 shrubs was examined in test fields in Norway and Poland. Leaf PM in different particle size fractions (PM(10), PM(2.5), PM(0.2)) differed among the species, by 10- to 15-folds at both test sites. Pinus mugo and Pinus sylvestris, Taxus media and Taxus baccata, Stephanandra incisa and Betula pendula were efficient species in capturing PM. Less efficient species were Acer platanoides, Prunus avium and Tilia cordata. Differences among species within the same genus were also observed. Important traits for PM accumulation were leaf properties such as hair and wax cover. The ranking presented in terms of capturing PM can be used to select species for air pollution removal in urban areas. Efficient plant species and planting designs that can shield vulnerable areas in urban settings from polluting traffic etc. can be used to decrease human exposure to anthropogenic pollutants. PMID:22554531

Sæbø, A; Popek, R; Nawrot, B; Hanslin, H M; Gawronska, H; Gawronski, S W

2012-06-15

125

Origin of Floral Isolation Between Ornithophilous and Sphingophilous Plant Species  

Microsoft Academic Search

Three plant groups in temperate western North America contain closely related ornithophilous and sphingophilous species: the Aquilegia formosa\\/Aquilegia caerulea group (Ranunculaceae), the Ipomopsis aggregata group (Polemoniaceae), and the Diplacus longiflorus group (Scrophulariaceae). The ornithophilous and sphingophilous species are products of allopatric speciation on the diploid level. Geographical races which are adapted to one class of pollinators in one area where

Verne Grant

1993-01-01

126

Induced responses in three alkaloid-containing plant species  

Microsoft Academic Search

In this paper we test three plant species for the inducibility of their alkaloid production. The plants were heavily damaged by cutting off 50% of their leaf surface using a pair of scissors. The cut-off leaf tips were used as controls for possible diurnal fluctuations. After 3, 6, 12, 24 and 48 h, respectively, the leaf bases of the damaged

Nicole M. van Dam; Ed van der Meijden; Robert Verpoorte

1993-01-01

127

The evolution of species concepts and species recognition criteria in plant pathogenic fungi  

Microsoft Academic Search

In this paper, we review historical and contemporary species concepts and species recognition criteria for plant pathogenic\\u000a fungi. Previous incongruent and unstable classification based on subjective and changing criteria have led to some confusion,\\u000a especially amongst plant pathologists. The goal of systematics is to provide an informative and robust framework that stands\\u000a the test of time. The taxonomic histories of

Lei Cai; Tatiana Giraud; Ning Zhang; Dominik Begerow; Guohong Cai; Roger G. Shivas

128

Ecological Effects of Roads on the Plant Diversity of Coastal Wetland in the Yellow River Delta  

PubMed Central

The 26 sample sites in 7 study plots adjacent to asphalt road and earth road in coastal wetland in the Yellow River Delta were selected to quantify plant diversity using quadrat sampling method in plant bloom phase of July and August 2012. The indice of ?T and Jaccard's coefficient were applied to evaluate the species diversity. The results showed that the plant diversities and alien plants were high in the range of 0–20?m to the road verge. There were more exotics and halophytes in plots of asphalt roadside than that of earth roadside. However, proportion of halophytes in habitats of asphalt roadsides was lower than that of earth roadside. By comparing ?-diversity, there were more common species in the asphalt roadsides than that in the earth roadsides. The similarity of plant communities in studied plots of asphalt roadsides and earth roadsides increased with increasing the distance to road verge. The effect range of roads for plant diversity in study region was about 20?m to road verge. Our results indicate that the construction and maintenance of roads in wetland could increase the plant species diversities of communities and risk of alien species invasion. PMID:25147872

Li, Yunzhao; Du, Siyao; Han, Guangxuan; Qu, Fanzhu; Wang, Guangmei; Fu, Yuqin; Zhan, Chao

2014-01-01

129

The role of succulent halophytes in the water balance of salt marsh rodents  

Microsoft Academic Search

The role of succulent halophytes in the water balance and ecology of salt marsh rodents is dependent upon an evaluation of the composition of the available sources and the physiological properties of their potential consumers. Studies of the osmotic properties of succulent halophytes from southern California coastal salt marshes are presented, together with experiments regarding the utilization of Common Pickleweed

Harry N. Coulombe

1970-01-01

130

Nutrient relations of the halophytic shrub, Sarcobatus vermiculatus, along a soil salinity gradient  

Microsoft Academic Search

Recent water level declines of a saline and alkaline lake (Mono Lake, California, USA) have exposed large areas of former lake bottom substrates that have been sparsely colonized by the halophytic shrub, Sarcobatus vermiculatus. To increase understanding of the interaction of salt and nutrient relations in halophytes we investigated spatial and seasonal patterns of leaf elemental composition and growth for

Lisa A. Donovan; James H. Richards; E. Joy Schaber

1997-01-01

131

The relative importance of the species pool, productivity and disturbance in regulating grassland plant species richness: a field experiment  

Microsoft Academic Search

Summary 1. Ecologists have generally focused on how species interactions and available niches control species richness. However, the number of species in the regional species pool may also control richness. Moreover, the relative influence of the species pool and species interactions on plant richness may change along productivity and disturbance gradients. 2. We test the hypothesis that many species from

Timothy L. Dickson; Bryan L. Foster

2008-01-01

132

No universal scale-dependent impacts of invasive species on native plant species richness.  

PubMed

A growing number of studies seeking generalizations about the impact of plant invasions compare heavily invaded sites to uninvaded sites. But does this approach warrant any generalizations? Using two large datasets from forests, grasslands and desert ecosystems across the conterminous United States, we show that (i) a continuum of invasion impacts exists in many biomes and (ii) many possible species-area relationships may emerge reflecting a wide range of patterns of co-occurrence of native and alien plant species. Our results contradict a smaller recent study by Powell et al. 2013 (Science 339, 316-318. (doi:10.1126/science.1226817)), who compared heavily invaded and uninvaded sites in three biomes and concluded that plant communities invaded by non-native plant species generally have lower local richness (intercepts of log species richness-log area regression lines) but steeper species accumulation with increasing area (slopes of the regression lines) than do uninvaded communities. We conclude that the impacts of plant invasions on plant species richness are not universal. PMID:24478201

Stohlgren, Thomas J; Rejmánek, Marcel

2014-01-01

133

Herbivore effects on plant species density at varying productivity levels  

USGS Publications Warehouse

Artificially increasing primary productivity decreases plant species richness in many habitats; herbivory may affect this outcome, but it has rarely been directly addressed in fertilization studies. This experiment was conducted in two Louisiana coastal marshes to examine the effects of nutrient enrichment and sediment addition on herbaceous plant communities with and without vertebrate herbivory. After three growing seasons, fertilization increased community biomass in all plots, but decreased species density (the number of species per unit area) only in plots protected from herbivory. Herbivory alone did not alter species density at either site. At the brackish marsh, herbivory caused a shift in dominance in the fertilized plots from a species that is considered the competitive dominant, but is selectively eaten, to another less palatable species. At the fresh marsh, increased dead biomass in the absence of herbivory and in the fertilized plots probably contributed to the decrease in species density, perhaps by limiting germination of annuals. Our results support those of other fertilization studies in which plant species density decreases with increased biomass, but only in those plots protected from herbivory.

Gough, L.; Grace, J.B.

1998-01-01

134

Floristic summary of plant species in the air pollution literature  

USGS Publications Warehouse

A floristic summary and analysis was performed on a list of the plant species that have been studied for the effects of gaseous and chemical air pollutants on vegetation in order to compare the species with the flora of North America north of Mexico. The scientific names of 2081 vascular plant species were extracted from almost 4000 journal articles stored in two large literature databases on the effects of air pollutants on plants. Three quarters of the plant species studied occur in North America, but this was only 7% of the total North American flora. Sixteen percent and 56% of all North American genera and families have been studied. The most studied genus is Pinus with 70% of the North American species studied, and the most studied family is the grass family, with 12% of the species studied. Although Pinus is ranked 86th in the North American flora, the grass family is ranked third, indicating that representation at the family level is better than at the genus level. All of the top ten families in North America are represented in the top 20 families in the air pollution effects literature, but only one genus (Lupinus) in the top ten genera in North America is represented in the top thirteen genera in the air pollution literature.

Bennett, J.P.

1996-01-01

135

Plant species richness regulates soil respiration through changes in productivity  

PubMed Central

Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of diversity on soil respiration. We hypothesized that plant diversity could affect soil respiration in two ways. On the one hand, more diverse plant communities have been shown to promote plant productivity, which could increase soil respiration. On the other hand, the nutrient concentration in the biomass produced has been shown to decrease with diversity, which could counteract the production-induced increase in soil respiration. Our results clearly show that soil respiration increased with species richness. Detailed analysis revealed that this effect was not due to differences in species composition. In general, soil respiration in mixtures was higher than would be expected from the monocultures. Path analysis revealed that species richness predominantly regulates soil respiration through changes in productivity. No evidence supporting the hypothesized negative effect of lower N concentration on soil respiration was found. We conclude that shifts in productivity are the main mechanism by which changes in plant diversity may affect soil respiration. Electronic supplementary material The online version of this article (doi:10.1007/s00442-010-1569-5) contains supplementary material, which is available to authorized users. PMID:20169454

van Ruijven, Jasper; Berendse, Frank

2010-01-01

136

Genetic variation within a dominant shrub species determines plant species colonization in a coastal dune ecosystem.  

PubMed

The diversity and structure of plant communities is often determined by the presence and identity of competitively dominant species. Recent studies suggest that intraspecific variation within dominants may also have important community-level consequences. In a coastal dunes ecosystem of northern California, we use a decade-old common garden experiment to test the effects of a genetically based architectural dimorphism within a dominant native shrub, Baccharis pilularis, on plant colonization success and understory plant diversity. We found that erect Baccharis morphs had higher richness and cover of colonizing plant species (both native and exotic species) compared to prostrate morphs, as well as higher biomass of a dominant exotic dune grass (Ammophila arenaria). Trait differences between architectural morphs influenced the abiotic understory environment (light availability, soil surface temperature, and litter depth) and were associated with species colonization success. Taken together, our results demonstrate that incorporating within-species variation, particularly within dominant species, into community ecological research can increase the ability to predict patterns of species diversity and assembly within communities. PMID:20462137

Crutsinger, Gregory M; Strauss, Sharon Y; Rudgers, Jennifer A

2010-04-01

137

Machine vision detection parameters for plant species identification  

NASA Astrophysics Data System (ADS)

Machine vision based on classical image processing techniques has the potential to be a useful tool for plant detection and identification. Plant identification is needed for weed detection, herbicide application or other efficient chemical spot spraying operations. The key to successful detection and identification of plants as species types is the segmentation of plants form background pixel regions. In particular, it would be beneficial to segment individual leaves form tops of canopies as well. The segmentation process yields an edge or binary image which contains shape feature information. Results indicate that red-green-blue formats might provide the best segmentation criteria, based on models of human color perception. The binary image can be also used as a template to investigate textural features of the plant pixel region, using gray image co-occurrence matrices. Texture features considers leaf venation, colors, or additional canopy structure that might be used to identify various type of grasses or broadleaf plants.

Meyer, George E.; Hindman, Timothy W.; Laksmi, Koppolu

1999-01-01

138

Germination in relation to salinity in some plants of salt marshes in Otago, New Zealand  

Microsoft Academic Search

Germination characteristics were examined for nine halophytes occurring on Otago salt marshes and were compared with two glycophytes. The seed of most halophytes remained dormant, but viable, in saline solution for at least several months. In comparison, of the two glycophyte species, one germinated in saline solution whereas the other suffered seed mortality. There was a correlation between the salt

T. R. Partridge; J. B. Wilson

1987-01-01

139

Regeneration niche differentiates functional strategies of desert woody plant species  

PubMed Central

Plant communities vary dramatically in the number and relative abundance of species that exhibit facilitative interactions, which contributes substantially to variation in community structure and dynamics. Predicting species’ responses to neighbors based on readily measurable functional traits would provide important insight into the factors that structure plant communities. We measured a suite of functional traits on seedlings of 20 species and mature plants of 54 species of shrubs from three arid biogeographic regions. We hypothesized that species with different regeneration niches—those that require nurse plants for establishment (beneficiaries) versus those that do not (colonizers)—are functionally different. Indeed, seedlings of beneficiary species had lower relative growth rates, larger seeds and final biomass, allocated biomass toward roots and height at a cost to leaf mass fraction, and constructed costly, dense leaf and root tissues relative to colonizers. Likewise at maturity, beneficiaries had larger overall size and denser leaves coupled with greater water use efficiency than colonizers. In contrast to current hypotheses that suggest beneficiaries are less “stress-tolerant” than colonizers, beneficiaries exhibited conservative functional strategies suited to persistently dry, low light conditions beneath canopies, whereas colonizers exhibited opportunistic strategies that may be advantageous in fluctuating, open microenvironments. In addition, the signature of the regeneration niche at maturity indicates that facilitation expands the range of functional diversity within plant communities at all ontogenetic stages. This study demonstrates the utility of specific functional traits for predicting species’ regeneration niches in hot deserts, and provides a framework for studying facilitation in other severe environments. Electronic supplementary material The online version of this article (doi:10.1007/s00442-010-1741-y) contains supplementary material, which is available to authorized users. PMID:20686787

Briggs, John M.

2010-01-01

140

Habitat origins and microhabitat preferences of urban plant species  

Microsoft Academic Search

Urban vegetation is commonly described as dominated by weedy species that are adapted to human disturbance. In this study,\\u000a we determined the original (pre-agriculture) habitats of urban plant species sampled quantitatively in the spontaneous vegetation\\u000a of a university campus in Halifax, Nova Scotia (eastern Canada). We sampled 11 distinct patch types corresponding to different\\u000a built forms. Differences in vegetation among

J. T. Lundholm; A. Marlin

2006-01-01

141

Leaf miner and plant galler species richness on Acacia : relative importance of plant traits and climate  

Microsoft Academic Search

Diversity patterns of herbivores have been related to climate, host plant traits, host plant distribution and evolutionary\\u000a relationships individually. However, few studies have assessed the relative contributions of a range of variables to explain\\u000a these diversity patterns across large geographical and host plant species gradients. Here we assess the relative influence\\u000a that climate and host plant traits have on endophagous

Katy A. Bairstow; Kerri L. Clarke; Melodie A. McGeoch; Nigel R. Andrew

2010-01-01

142

Metal species involved in long distance metal transport in plants  

PubMed Central

The mechanisms plants use to transport metals from roots to shoots are not completely understood. It has long been proposed that organic molecules participate in metal translocation within the plant. However, until recently the identity of the complexes involved in the long-distance transport of metals could only be inferred by using indirect methods, such as analyzing separately the concentrations of metals and putative ligands and then using in silico chemical speciation software to predict metal species. Molecular biology approaches also have provided a breadth of information about putative metal ligands and metal complexes occurring in plant fluids. The new advances in analytical techniques based on mass spectrometry and the increased use of synchrotron X-ray spectroscopy have allowed for the identification of some metal-ligand species in plant fluids such as the xylem and phloem saps. Also, some proteins present in plant fluids can bind metals and a few studies have explored this possibility. This study reviews the analytical challenges researchers have to face to understand long-distance metal transport in plants as well as the recent advances in the identification of the ligand and metal-ligand complexes in plant fluids. PMID:24723928

Alvarez-Fernandez, Ana; Diaz-Benito, Pablo; Abadia, Anunciacion; Lopez-Millan, Ana-Flor; Abadia, Javier

2014-01-01

143

Multivariate forecasts of potential distributions of invasive plant species  

Microsoft Academic Search

The fact that plant invasions are an ongoing process makes generalizations of invasive spread extraordinarily challenging. This is particularly true given the idiosyncratic nature of invasions, in which both historical and local conditions affect establishment success and hinder our ability to generate guidelines for early detection and eradication of invasive species. To overcome these limitations we have implemented a comprehensive

Inés Ibáñez; John A. Silander; Adam M. Wilson; Nancy LaFleur; Nobuyuki Tanaka; Ikutaro Tsuyama

2009-01-01

144

Effect of Burning on Germination of Tallgrass Prairie Plant Species  

Microsoft Academic Search

Seeds from 10 prairie plant species of burned and unburned portions of three tallgrass prairies were collected and tested for germinability. Germination of big bluestem (Andropogon gerardii Vitman) consistently averaged higher with burning. Indiangrass (Sorghastrum nutans L.) and sideoats grama [Bouteloua curtipendula (Michx.) Torr.] averaged 5% higher with burning on two of the three sites, although for indiangrass average germination

Sherry R. Rohn; Thomas B. Bragg

1989-01-01

145

Emergence and growth of plant species in coal mine soil  

Microsoft Academic Search

Experiments were conducted in the laboratory and greenhouse in Arizona with the following objectives: to evaluate the chemical properties of undisturbed soil, surface-mined coal land (coal mine soil) on the Black Mesa Coal Mine, and Gila loam soil; and to study the emergence of seven plant species in the greenhouse in Gila loam soil and coal mine soil. The pH

A. D. Day; G. F. Mitchell; T. C. Tucker; J. L. Thames

1979-01-01

146

Response of plant species to coal-mine soil materials  

Microsoft Academic Search

A two-year experiment was conducted on the Black Mesa Coal Mine near Kayenta, Arizona to investigate the growth and establishment of seven plant species in unmined soil (undisturbed soil) and coal-mine soil (spoils). Natural rainfall (20 cm\\/yr) and natural rainfull plus sprinkler irrigation (50 cm\\/yr) were the irrigation treatments applied to each soil material.

A. D. Day; T. C. Tucker; J. L. Thamest

1983-01-01

147

ORGANIC PESTICIDE MODIFICATION OF SPECIES INTERACTIONS USING ANNUAL PLANT COMMUNITIES  

EPA Science Inventory

A method is proposed and tested for assessing multispecies responses to three pesticides (atrazine, 2,4,D and malathion). Pesticides were applied at two concentrations, mon model plant communities grown in raised beds using soil containing a natural weed bank. over by species was...

148

Plant roots and spectroscopic methods - analyzing species, biomass and vitality.  

PubMed

In order to understand plant functioning, plant community composition, and terrestrial biogeochemistry, it is decisive to study standing root biomass, (fine) root dynamics, and interactions belowground. While most plant taxa can be identified by visual criteria aboveground, roots show less distinctive features. Furthermore, root systems of neighboring plants are rarely spatially segregated; thus, most soil horizons and samples hold roots of more than one species necessitating root sorting according to taxa. In the last decades, various approaches, ranging from anatomical and morphological analyses to differences in chemical composition and DNA sequencing were applied to discern species' identity and biomass belowground. Among those methods, a variety of spectroscopic methods was used to detect differences in the chemical composition of roots. In this review, spectroscopic methods used to study root systems of herbaceous and woody species in excised samples or in situ will be discussed. In detail, techniques will be reviewed according to their usability to discern root taxa, to determine root vitality, and to quantify root biomass non-destructively or in soil cores holding mixtures of plant roots. In addition, spectroscopic methods which may be able to play an increasing role in future studies on root biomass and related traits are highlighted. PMID:24130565

Rewald, Boris; Meinen, Catharina

2013-01-01

149

Plant roots and spectroscopic methods - analyzing species, biomass and vitality  

PubMed Central

In order to understand plant functioning, plant community composition, and terrestrial biogeochemistry, it is decisive to study standing root biomass, (fine) root dynamics, and interactions belowground. While most plant taxa can be identified by visual criteria aboveground, roots show less distinctive features. Furthermore, root systems of neighboring plants are rarely spatially segregated; thus, most soil horizons and samples hold roots of more than one species necessitating root sorting according to taxa. In the last decades, various approaches, ranging from anatomical and morphological analyses to differences in chemical composition and DNA sequencing were applied to discern species’ identity and biomass belowground. Among those methods, a variety of spectroscopic methods was used to detect differences in the chemical composition of roots. In this review, spectroscopic methods used to study root systems of herbaceous and woody species in excised samples or in situ will be discussed. In detail, techniques will be reviewed according to their usability to discern root taxa, to determine root vitality, and to quantify root biomass non-destructively or in soil cores holding mixtures of plant roots. In addition, spectroscopic methods which may be able to play an increasing role in future studies on root biomass and related traits are highlighted. PMID:24130565

Rewald, Boris; Meinen, Catharina

2013-01-01

150

Spatial connectedness of plant species: potential links for apparent competition via plant diseases  

E-print Network

. Bouteloua curtipendula was uncommon but occurred in all environments, while Buchloe dactyloides and Bouteloua gracilis were uncommon and only occurred in upland sites. Co-occurrence of plant species

Garrett, Karen A.

151

Stakeholders' perceptions of the impacts of invasive exotic plant species in the Mediterranean region  

E-print Network

Stakeholders' perceptions of the impacts of invasive exotic plant species in the Mediterranean, exotic plants, invasive species, landscape, Likert analysis, Mediterra- nean, stakeholder perception Abstract Invasive species pose an increasing environmental problem across the globe, but to date socio

Boudouresque, Charles F.

152

45 CFR 670.25 - Designation of specially protected species of native mammals, birds, and plants.  

Code of Federal Regulations, 2012 CFR

...species of native mammals, birds, and plants. 670.25 Section 670.25 Public... CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Specially Protected Species of Mammals, Birds, and Plants § 670.25 Designation of...

2012-10-01

153

Tocopherol content and isomers' composition in selected plant species.  

PubMed

We have analyzed leaves of several plant species for the content and isomers' composition of tocopherols and it was found that their content was considerably higher in some cases than previously reported, especially in autumn tree leaves where the average tocopherols' level was in the range of 300-640 microg/g fresh weight and accounted for 40-140% of the chlorophyll amount. The isomers' composition, usually dominated by alpha-tocopherol in leaves, was different in some plant species with a high percentage of gamma-tocopherol (Kalanchoe, lettuce, dodder species, and young maple leaves) or delta-tocopherol (Cuscuta epithymum and Cuscuta japonica). C. japonica was exceptional by the complete absence of alpha-tocopherol. The possible reasons and physiological significance of these observations have been discussed. PMID:18023194

Szyma?ska, Renata; Kruk, Jerzy

2008-01-01

154

Plant species richness and ecosystem multifunctionality in global drylands  

USGS Publications Warehouse

Experiments suggest that biodiversity enhances the ability of ecosystems to maintain multiple functions, such as carbon storage, productivity, and the buildup of nutrient pools (multifunctionality). However, the relationship between biodiversity and multifunctionality has never been assessed globally in natural ecosystems. We report here on a global empirical study relating plant species richness and abiotic factors to multifunctionality in drylands, which collectively cover 41% of Earth's land surface and support over 38% of the human population. Multifunctionality was positively and significantly related to species richness. The best-fitting models accounted for over 55% of the variation in multifunctionality and always included species richness as a predictor variable. Our results suggest that the preservation of plant biodiversity is crucial to buffer negative effects of climate change and desertification in drylands.

Maestre, Fernando T.; Quero, Jose L.; Gotelli, Nicholas J.; Escudero, Adrian; Ochoa, Victoria; Delgado-Baquerizo, Manuel; Garcia-Gomez, Miguel; Bowker, Matthew A.; Soliveres, Santiago; Escolar, Cristina; Garcia-Palacios, Pablo; Berdugo, Miguel; Valencia, Enrique; Gozalo, Beatriz; Gallardo, Antonio; Aguilera, Lorgio; Arredondo, Tulio; Blones, Julio; Boeken, Bertrand; Bran, Donaldo; Conceicao, Abel A.; Cabrera, Omar; Chaieb, Mohamed; Derak, Mchich; Eldridge, David J.; Espinosa, Carlos I.; Florentino, Adriana; Gaitan, Juan; Gatica, M. Gabriel; Ghiloufi, Wahida; Gomez-Gonzalez, Susana; Gutie, Julio R.; Hernandez, Rosa M.; Huang, Xuewen; Huber-Sannwald, Elisabeth; Jankju, Mohammad; Miriti, Maria; Monerris, Jorge; Mau, Rebecca L.; Morici, Ernesto; Naseri, Kamal; Ospina, Abelardo; Polo, Vicente; Prina, Anibal; Pucheta, Eduardo; Ramirez-Collantes, David A.; Romao, Roberto; Tighe, Matthew; Torres-Diaz, Cristian; Val, James; Veiga, Jose P.; Wang, Deli; Zaady, Eli

2012-01-01

155

Plant species richness and ecosystem multifunctionality in global drylands  

PubMed Central

Experiments suggest that biodiversity enhances the ability of ecosystems to maintain multiple functions, such as carbon storage, productivity, and buildup of nutrient pools (multifunctionality). However, the relationship between biodiversity and multifunctionality has never been assessed globally in natural ecosystems. We report on the first global empirical study relating plant species richness and abiotic factors to multifunctionality in drylands, which collectively cover 41% of Earth’s land surface and support over 38% of the human population. Multifunctionality was positively and significantly related to species richness. The best-fitting models accounted for over 55% of the variation in multifunctionality, and always included species richness as a predictor variable. Our results suggest that preservation of plant biodiversity is crucial to buffer negative effects of climate change and desertification in drylands. PMID:22246775

Maestre, Fernando T.; Quero, José L.; Gotelli, Nicholas J.; Escudero, Adriá; Ochoa, Victoria; Delgado-Baquerizo, Manuel; García-Gómez, Miguel; Bowker, Matthew A.; Soliveres, Santiago; Escolar, Cristina; García-Palacios, Pablo; Berdugo, Miguel; Valencia, Enrique; Gozalo, Beatriz; Gallardo, Antonio; Aguilera, Lorgio; Arredondo, Tulio; Blones, Julio; Boeken, Bertrand; Bran, Donaldo; Conceição, Abel A.; Cabrera, Omar; Chaieb, Mohamed; Derak, Mchich; Eldridge, David J.; Espinosa, Carlos I.; Florentino, Adriana; Gaitán, Juan; Gatica, M. Gabriel; Ghiloufi, Wahida; Gómez-González, Susana; Gutiérrez, Julio R.; Hernández, Rosa M.; Huang, Xuewen; Huber-Sannwald, Elisabeth; Jankju, Mohammad; Miriti, Maria; Monerris, Jorge; Mau, Rebecca L.; Morici, Ernesto; Naseri, Kamal; Ospina, Abelardo; Polo, Vicente; Prina, Aníbal; Pucheta, Eduardo; Ramírez-Collantes, David A.; Romão, Roberto; Tighe, Matthew; Torres-Díaz, Cristian; Val, James; Veiga, José P.; Wang, Deli; Zaady, Eli

2013-01-01

156

[Analysis of gene expression involved in the response to salt stress in the dicot halophyte Kosteletzkya virginica L. seedlings].  

PubMed

Kosteletzkya virginica L. Presl. is an obligate wetland species indigenous to southeastern US. Its niche in salt marsh foretells its high salinity tolerance. cDNA-AFLP technique was used to identify the gene transcriptional profiles of leaves and roots from K. virginica seedlings under salt stress in order to clarify the molecular architecture of stress tolerance in the dicot halophyte. Expression analysis over time intervals and under various salt stresses in leaves or roots showed that the quantitatively expressed pattern (in which genes were quantitatively up- or down-regulated under salt stress or fluctuate with different NaCl concentrations) was more prevalent than the qualitatively expressed pattern (in which genes were induced or silenced under salt stress) in K. virginica seedlings under salt stress. The qualitative pattern was appreciably more predominant than the quantitative one only in roots when exposed to salt stress for 2 h. Although each expression pattern was observed in leaves as well as in roots, the percentage of genes (i.e., up-/down-regulated or induced/silenced under salt stress) was dynamically changeable under salt stress at different time intervals. All these results indicated that there was no established formula of gene expression patterns in deciphering the sophisticated mechanism of plant salinity tolerance, considering that plants undergo a series of dynamically physiological and metabolic pathways in sensing and response to salt stress for different tissues and during different stages of stress. A number of Trivially distributed file system (TDFs) up-regulated or induced under salt stress from leaves and roots were sequenced, and the sequences were blasted against the NCBI non-redundant protein database using translated nucleotide query (Blastx). The TDFs from K. virginica seedlings involved in sensing and response to salt stress can be classified at least into three groups according to their putative functions: (1) genes for re-establishing ionic homeostasis or preventing from damage (specially genes for transporter); (2) genes for resuming plant growth and development under salt stress, such as key enzymes involved in energy synthesis or hormone regulatory pathway; (3) genes for signal transduction and so on. The relationship of expression patterns of these TDFs with the molecular mechanism of salt tolerance in K. virginica was discussed. PMID:18779140

Guo, Yu-Qi; Tian, Zeng-Yuan; Yan, Dao-Liang; Zhang, Jie; Qin, Pei

2008-07-01

157

Reprints Available from the Halophyte Biotechnology Center  

E-print Network

.M. Seliskar, and H.P. Bais. 2007. Root-secreted allelochemical in the noxious weed Phragmites australis. Blocking Phragmites australis reinvasion of restored marshes using plants selected from wild populations of Phragmites australis (common reed). Estuaries 29: 269-276. Seliskar, D.M. and J.L. Gallagher. 2005. Tidal

Firestone, Jeremy

158

Biogenic volatile organic compounds from an invasive species: impacts on plant–plant interactions  

Microsoft Academic Search

Invasive plant species impact both ecosystems and economies worldwide, often by displacing native biota. Many plant species\\u000a exude\\/emit compounds into the surrounding environment with minor consequences in their native habitat due to a long coevolutionary\\u000a history. However, upon introduction to ecosystems naïve to these compounds, unpredictable interactions can manifest. The majority\\u000a of the putative allelochemicals studied have been root exudates,

Jacob N. Barney; Jed P. Sparks; Jim Greenberg; Thomas H. Whitlow; Alex Guenther

2009-01-01

159

Plant species controls on atmospheric CH4 oxidation by soil  

NASA Astrophysics Data System (ADS)

Plant species exert strong effects on ecosystem functions and one of the emerging, and difficult to test hypotheses, is that plants alter soil functions through changing the community structure of soil microorganisms. We tested the hypothesis for atmospheric CH4 oxidation by using soil samples from a Siberian afforestation experiment and exposing them to 13C-CH4. We determined the activity of the soil methanotrophs under different tree species at three levels of initial CH4 concentration (30, 200 and 1000 ppm) thus distinguishing the activities of low- and high-affinity methanotrophs. Half of the samples were incubated with 13C-enriched CH4 (99.9%) and half with 12C-CH4. This allowed an estimation of the amount of 13C incorporated into individual PLFAs and determination of PLFAs of methanotrophs involved in CH4 oxidation at the different CH4 concentrations. Tree species strongly altered the activity of atmospheric CH4 oxidation without appearing to change the composition of high-affinity methanotrophs as evidenced by PLFA 13C labeling. The low diversity of atmospheric CH4 oxidizers, presumably belonging to the UCS? group, may explain the lack of tree species effects on the composition of soil methanotrophs. We submit that the observed tree species effects on atmospheric CH4 oxidation indicate an effect on biomass or cell-specific activities rather than by a community change and this may be related to the impact of the tree species on soil N cycling.

Menyailo, O. V.; Abraham, W.; Conrad, R.

2009-12-01

160

Grazing-induced changes in plant species composition affect plant and soil properties of grassland mesocosms  

Microsoft Academic Search

Grazing-induced floristic changes in plant communities may accelerate or reduce plant and soil processes through changes in\\u000a litter quality. Here, we intended to elucidate if the joint action of live and senescing plant tissue of palatable and non-palatable\\u000a species differentially influences soil processes and properties. We conducted a 1-year experiment with mesocosms from a subhumid\\u000a grassland. Mesocosms were monocultures of

María Semmartin; Carla Di Bella; Inés García de Salamone

2010-01-01

161

Plant species richness increases phosphatase activities in an experimental grassland  

NASA Astrophysics Data System (ADS)

Plant species richness has been shown to increase aboveground nutrient uptake requiring the mobilization of soil nutrient pools. For phosphorus (P) the underlying mechanisms for increased P release in soil under highly diverse grassland mixtures remain obscure because aboveground P storage and concentrations of inorganic and organic P in soil solution and differently reactive soil P pools are unrelated (Oelmann et al. 2011). The need of plants and soil microorganisms for P can increase the exudation of enzymes hydrolyzing organically bound P (phosphatases) which might represent an important release mechanism of inorganic P in a competitive environment such as highly diverse grassland mixtures. Our objectives were to test the effects of i) plant functional groups (legumes, grasses, non-leguminous tall and small herbs), and of (ii) plant species richness on microbial P (Pmic) and phosphatase activities in soil. In autumn 2013, we measured Pmic and alkaline phosphomonoesterase and phosphodiesterase activities in soil of 80 grassland mixtures comprising different community compositions and species richness (1, 2, 4, 8, 16, 60) in the Jena Experiment. In general, Pmic and enzyme activities were correlated (r = 0.59 and 0.46 for phosphomonoesterase and phosphodiesterase activities, respectively; p

Hacker, Nina; Wilcke, Wolfgang; Oelmann, Yvonne

2014-05-01

162

Local and regional abundance of exotic plant species on Mediterranean islands: are species traits important?  

Microsoft Academic Search

Aim We assess the importance of three relevant and readily obtainable life- history traits (dispersal syndrome, stem height and growth form) and biogeographical origin (European vs. non-European) on the local and regional abundance of over 400 exotic plant species across eight Mediterranean islands. Location The Mediterranean islands of Lesbos, Rhodes, Crete, Malta, Corsica, Sardinia, Majorca and Minorca. Methods We adopt

Francisco Lloret; Fréderic Médail; Giuseppe Brundu; Philip E. Hulme; Aberdeenshire AB

2004-01-01

163

Variation in grazing tolerance among three tallgrass prairie plant species.  

PubMed

Three tallgrass prairie plant species, two common perennial forbs (Artemisia ludoviciana and Aster ericoides [Asteraceae]) and a dominant C(4) perennial grass (Sorghastrum nutans) were studied under field and greenhouse conditions to evaluate interspecific variation in grazing tolerance (compensatory growth capacity). Adaptation to ungulate grazing was also assessed by comparing defoliation responses of plants from populations with a 25-yr history of no grazing or moderate ungulate grazing. Under field conditions, all three species showed significant reductions in shoot relative growth rates (RGR), biomass, and reproduction with defoliation. In the two forbs, clipping resulted in negative shoot RGR and reductions in both number and length of shoot branches per ramet. Sorghastrum nutans maintained positive RGR under defoliation due to a compensatory increase in leaf production. Defoliation reduced rhizome production in A. ericoides and S. nutans, but not in A. ludoviciana. Clipping significantly reduced sexual reproductive allocation in all three species, although S. nutans showed a smaller reduction than the forbs. All three species showed similar responses to defoliation in burned and unburned sites. Under greenhouse conditions, a similar clipping regimen resulted in smaller reductions in growth and reproduction than those observed in the field. For all three species, the grazing tolerance indices calculated under natural field conditions were significantly lower than those estimated from greenhouse-grown plants, and the interspecific patterns of grazing tolerance were different. Aster ericoides exhibited the highest overall defoliation tolerance under greenhouse conditions, followed by S. nutans. Artemisia ludoviciana, the only study species that is typically not grazed by ungulates in the field, showed the lowest grazing tolerance. In the field experiment S. nutans showed the highest grazing tolerance and the two forbs had similar low tolerance indices. These patterns indicate that, despite high compensatory growth potential, limited resource availability and competition in the field significantly reduce the degree of compensation and alter interspecific differences in grazing tolerance among prairie plants. In all three species, defoliation suppressed sexual reproduction more than growth or vegetative reproduction. Significant interactions between plant responses to defoliation and site of origin (historically grazed or ungrazed sites) for some response variables (root/shoot ratios, rhizome bud initiation, and reproductive allocation) indicated some degree of population differentiation and genetic adaptation in response to a relatively short history of ungulate grazing pressure. The results of this study indicate that patterns of grazing tolerance in tallgrass prairie are both genetically based and also environmentally dependent. PMID:21665591

Damhoureyeh, Said A; Hartnett, David C

2002-10-01

164

Methylated arsenic species in plants originate from soil microorganisms.  

PubMed

• Inorganic arsenic (iAs) is a ubiquitous human carcinogen, and rice (Oryza sativa) is the main contributor to iAs in the diet. Methylated pentavalent As species are less toxic and are routinely found in plants; however, it is currently unknown whether plants are able to methylate As. • Rice, tomato (Solanum lycopersicum) and red clover (Trifolium pratense) were exposed to iAs, monomethylarsonic acid (MMA(V)), or dimethylarsinic acid (DMA(V)), under axenic conditions. Rice seedlings were also grown in two soils under nonsterile flooded conditions, and rice plants exposed to arsenite or DMA(V) were grown to maturity in nonsterile hydroponic culture. Arsenic speciation in samples was determined by HPLC-ICP-MS. • Methylated arsenicals were not found in the three plant species exposed to iAs under axenic conditions. Axenically grown rice was able to take up MMA(V) or DMA(V), and reduce MMA(V) to MMA(III) but not convert it to DMA(V). Methylated As was detected in the shoots of soil-grown rice, and in rice grain from nonsterile hydroponic culture. GeoChip analysis of microbial genes in a Bangladeshi paddy soil showed the presence of the microbial As methyltransferase gene arsM. • Our results suggest that plants are unable to methylate iAs, and instead take up methylated As produced by microorganisms. PMID:22098145

Lomax, Charlotte; Liu, Wen-Ju; Wu, Liyou; Xue, Kai; Xiong, Jinbo; Zhou, Jizhong; McGrath, Steve P; Meharg, Andrew A; Miller, Anthony J; Zhao, Fang-Jie

2012-02-01

165

Species differences in whole plant carbon balance following winter dormancy in Alaskan tundra plants  

SciTech Connect

We froze ramets of seven vascular plant species and a mixed community of mosses common to upland tussock tundra for several months, then measured whole-plant photosynthesis and respiration in a growth chamber under simulated spring conditions, to examine whole plant carbon metabolism following winter dormancy. In addition, respiration and photosynthesis of aboveground stems and leaves were measured in the field in a spatial gradient away from a melting snowbank, at comparable developmental stages. Species differences in early respiration were not pronounced, but large differences were seen once development of leaves began. Root development in deciduous shrubs delayed their attainment of a positive whole plant carbon balance compared to that seen in aboveground stems and leaves alone, and partially compensated for differences in photosynthetic rates between shrubs and other species. Temporal patterns of carbon metabolism during spring growth may affect competitive balance in tussock tundra and vegetation response to global change.

Bret-Harte, M.S.; Chapin, F.S. III [Univ. of California, Berkeley, CA (United States)

1995-09-01

166

Cupriavidus plantarum sp. nov., a plant-associated species.  

PubMed

During a survey of plant-associated bacteria in northeast Mexico, a group of 13 bacteria was isolated from agave, maize and sorghum plants rhizosphere. This group of strains was related to Cupriavidus respiraculi (99.4 %), but a polyphasic investigation based on DNA-DNA hybridization analysis, other genotypic studies and phenotypic features showed that this group of strains actually belongs to a new Cupriavidus species. Consequently, taking all the results together, the description of Cupriavidus plantarum sp. nov. is proposed. PMID:25098225

Estrada-de Los Santos, Paulina; Solano-Rodríguez, Roosivelt; Matsumura-Paz, Lucía Tomiko; Vásquez-Murrieta, María Soledad; Martínez-Aguilar, Lourdes

2014-11-01

167

Photochemical and biophysical feedbacks of C? and C? Mediterranean halophytes to atmospheric CO? enrichment confirmed by their stable isotope signatures.  

PubMed

According the latest predictions, an increase of about two times in atmospheric CO2 concentrations, is expected to occur by the end of this century. In order to understand the effects of this atmospheric composition changes on two abundant Mediterranean halophytes (Halimione portulacoides and Spartina maritima), mesocosmos trials were performed simulating two atmospheric CO2 environments (380 ppm and 760 ppm of CO2 respectively). The two chosen halophyte species present different metabolic characteristics: H. portulacoides, is a C3 specie while S. maritima is a C4 species. Distinct feedbacks were obtained for each of the studied species. Stable Isotope discrimination showed that both species showed an enhancement of the Rubisco carboxylation capacity and photosynthetic efficiency mostly due to an increase in intracellular [CO2]. In H. portulacoides CO2 fertilization induced an enhancement of ETR and a decrease in non-photochemical quenching and in dissipated energy fluxes. On the other hand the C4 grass S. maritima, already at full capacity, showed no photosynthetic enhancement. In fact this highly productive grass presented lower photosynthetic efficiencies accompanied by increases in dissipated energy fluxes mostly due to reductions in energy flux associated with the transport of reducing power throughout the quinone pool. The accumulation of reducing power led to oxidative stress, and thus the photosynthetic ability of this grass was greatly reduced. Both these feedbacks to realistic future CO2 concentrations are important consideration for in future primary productivity models, indicating a possible reduced abundance of the pioneer S. maritima and an increased biomass spreading of the sediment stabilizer H. portulacoides, inevitably affecting the morphology and function of the salt marshes imposed by these atmospheric changes, both in terms of ecosystem functioning and loss of biodiversity. PMID:24713121

Duarte, B; Santos, D; Silva, H; Marques, J C; Caçador, I

2014-07-01

168

Different Arbuscular Mycorrhizal Fungal Species Are Potential Determinants of Plant Community Structure  

Microsoft Academic Search

Almost all natural plant communities contain arbuscular mycorrhizal fungi (AMF). We hypothesized that the species composition of AMF communities could have the potential to determine plant community structure if the growth response to different AMF species or to communities of AMF species varies among plant species. To test the existence of such a differential response we conducted a pot experiment

Thomas Boller; Andres Wiemken; Ian R. Sanders

1998-01-01

169

Origin of floral isolation between ornithophilous and sphingophilous plant species.  

PubMed

Three plant groups in temperate western North America contain closely related ornithophilous and sphingophilous species: the Aquilegia formosa/Aquilegia caerulea group (Ranunculaceae), the Ipomopsis aggregata group (Polemoniaceae), and the Diplacus longiflorus group (Scrophulariaceae). The ornithophilous and sphingophilous species are products of allopatric speciation on the diploid level. Geographical races which are adapted to one class of pollinators in one area where these pollinators are abundant and effective and to another class of pollinators in another geographically isolated area (pollination races) represent a probable intermediate stage in the process of allopatric speciation. Mechanical and ethological isolation (collectively, floral isolation) is a byproduct of the divergence in pollination systems. Selection for reproductive isolation per se has not played any detectable role in the origin of the floral isolation in the three plant groups. PMID:11607421

Grant, V

1993-08-15

170

Origin of floral isolation between ornithophilous and sphingophilous plant species.  

PubMed Central

Three plant groups in temperate western North America contain closely related ornithophilous and sphingophilous species: the Aquilegia formosa/Aquilegia caerulea group (Ranunculaceae), the Ipomopsis aggregata group (Polemoniaceae), and the Diplacus longiflorus group (Scrophulariaceae). The ornithophilous and sphingophilous species are products of allopatric speciation on the diploid level. Geographical races which are adapted to one class of pollinators in one area where these pollinators are abundant and effective and to another class of pollinators in another geographically isolated area (pollination races) represent a probable intermediate stage in the process of allopatric speciation. Mechanical and ethological isolation (collectively, floral isolation) is a byproduct of the divergence in pollination systems. Selection for reproductive isolation per se has not played any detectable role in the origin of the floral isolation in the three plant groups. PMID:11607421

Grant, V

1993-01-01

171

Harmful plant species entering New Zealand 1963–1967  

Microsoft Academic Search

Potentially harmful plant species, mainly as seed, are continually entering New Zealand from many parts of the world. During 1963–67 over 1,500 items of botanical interest have been intercepted by the Department of Agriculture§ Port Agriculture Inspection Service and identified to specific or generic level at the Levin Horticultural Laboratory.Of significant interest were 116 interceptions which included propagules of 65

Richard H. Powell

1968-01-01

172

Tocopherol content and isomers' composition in selected plant species  

Microsoft Academic Search

We have analyzed leaves of several plant species for the content and isomers' composition of tocopherols and it was found that their content was considerably higher in some cases than previously reported, especially in autumn tree leaves where the average tocopherols' level was in the range of 300–640?g\\/g fresh weight and accounted for 40–140% of the chlorophyll amount. The isomers'

Renata Szyma?ska; Jerzy Kruk

2008-01-01

173

Reactive Oxygen Species, Oxidative Stress and Plant Ion Channels  

Microsoft Academic Search

\\u000a Reactive oxygen species (ROS) are important toxic and regulatory agents in plants. They are produced in response to a number\\u000a of stimuli, including major biotic and abiotic stresses. Disruption of respiratory and photosynthetic electron transport chains,\\u000a as well as activation of NADPH oxidases (NOXs) and peroxidases, is a major reason for ROS generation and accumulation during\\u000a stress conditions. ROS production

Vadim Demidchik

174

Nuclear DNA content of some important plant species  

Microsoft Academic Search

Nuclear DNA contents of more than 100 important plant species were measured by flow cytometry of isolated nuclei stained with\\u000a propidium iodide.Arabidopsis exhibits developmentally regulated multiploidy and has a 2C nuclear DNA content of 0.30 pg (145 Mbp\\/1C), twice the value\\u000a usually cited. The 2C value for rice is only about three times that ofArabidopsis. Tomato has a 2C value

K. Arumuganathan; E. D. Earle

1991-01-01

175

Reactive Oxygen Species in Plant–Pathogen Interactions  

Microsoft Academic Search

Reactive oxygen species (ROS), superoxide, hydrogen peroxide and nitric oxide are produced at all levels of resistance reactions\\u000a in plants. In basal resistance, they are linked to papilla formation and the assembly of barriers. In the hypersensitive response,\\u000a they may be linked to programmed cell death, and in systemic acquired resistance, they interact with salicylate in signalling.\\u000a Despite this importance,

G. Paul Bolwell; Arsalan Daudi

176

Does phosphorus limitation promote species-rich plant communities?  

Microsoft Academic Search

It is known that the number of limiting nutrients may affect the species richness of plant communities, but it is unclear\\u000a whether the type of nutrient limitation is also important. I place the results from a study in Patagonia (elsewhere in this\\u000a issue) in the context of the number and types of nutrients that are limiting. I present four mechanisms

Harry Olde Venterink

177

Pollinators visit related plant species across 29 plant-pollinator networks  

PubMed Central

Understanding the evolution of specialization in host plant use by pollinators is often complicated by variability in the ecological context of specialization. Flowering communities offer their pollinators varying numbers and proportions of floral resources, and the uniformity observed in these floral resources is, to some degree, due to shared ancestry. Here, we find that pollinators visit related plant species more so than expected by chance throughout 29 plant–pollinator networks of varying sizes, with “clade specialization” increasing with community size. As predicted, less versatile pollinators showed more clade specialization overall. We then asked whether this clade specialization varied with the ratio of pollinator species to plant species such that pollinators were changing their behavior when there was increased competition (and presumably a forced narrowing of the realized niche) by examining pollinators that were present in at least three of the networks. Surprisingly, we found little evidence that variation in clade specialization is caused by pollinator species changing their behavior in different community contexts, suggesting that clade specialization is observed when pollinators are either restricted in their floral choices due to morphological constraints or innate preferences. The resulting pollinator sharing between closely related plant species could result in selection for greater pollinator specialization. PMID:25360269

Vamosi, Jana C; Moray, Clea M; Garcha, Navdeep K; Chamberlain, Scott A; Mooers, Arne ?

2014-01-01

178

Consequences of plant invasions on compartmentalization and species' roles in plant-pollinator networks.  

PubMed

Compartmentalization-the organization of ecological interaction networks into subsets of species that do not interact with other subsets (true compartments) or interact more frequently among themselves than with other species (modules)-has been identified as a key property for the functioning, stability and evolution of ecological communities. Invasions by entomophilous invasive plants may profoundly alter the way interaction networks are compartmentalized. We analysed a comprehensive dataset of 40 paired plant-pollinator networks (invaded versus uninvaded) to test this hypothesis. We show that invasive plants have higher generalization levels with respect to their pollinators than natives. The consequences for network topology are that-rather than displacing native species from the network-plant invaders attracting pollinators into invaded modules tend to play new important topological roles (i.e. network hubs, module hubs and connectors) and cause role shifts in native species, creating larger modules that are more connected among each other. While the number of true compartments was lower in invaded compared with uninvaded networks, the effect of invasion on modularity was contingent on the study system. Interestingly, the generalization level of the invasive plants partially explains this pattern, with more generalized invaders contributing to a lower modularity. Our findings indicate that the altered interaction structure of invaded networks makes them more robust against simulated random secondary species extinctions, but more vulnerable when the typically highly connected invasive plants go extinct first. The consequences and pathways by which biological invasions alter the interaction structure of plant-pollinator communities highlighted in this study may have important dynamical and functional implications, for example, by influencing multi-species reciprocal selection regimes and coevolutionary processes. PMID:24943368

Albrecht, Matthias; Padrón, Benigno; Bartomeus, Ignasi; Traveset, Anna

2014-08-01

179

Influence of herbivores on a perennial plant: variation with life history stage and herbivore species  

Microsoft Academic Search

Herbivores have diverse impacts on their host plants, potentially altering survival, growth, fecundity, and other aspects of plant performance. Especially for longer-lived plant species, the effects of a single herbivore species can vary markedly throughout the life of the host plant. In addition, the effects of herbivory during any given life history stage of a host plant may also vary

Peter J. Warner; Hall J. Cushman

2002-01-01

180

Effects of 'Target' Plant Species Body Size on Neighbourhood Species Richness and Composition in Old-Field Vegetation  

PubMed Central

Competition is generally regarded as an important force in organizing the structure of vegetation, and evidence from several experimental studies of species mixtures suggests that larger mature plant size elicits a competitive advantage. However, these findings are at odds with the fact that large and small plant species generally coexist, and relatively smaller species are more common in virtually all plant communities. Here, we use replicates of ten relatively large old-field plant species to explore the competitive impact of target individual size on their surrounding neighbourhoods compared to nearby neighbourhoods of the same size that are not centred by a large target individual. While target individuals of the largest of our test species, Centaurea jacea L., had a strong impact on neighbouring species, in general, target species size was a weak predictor of the number of other resident species growing within its immediate neighbourhood, as well as the number of resident species that were reproductive. Thus, the presence of a large competitor did not restrict the ability of neighbouring species to reproduce. Lastly, target species size did not have any impact on the species size structure of neighbouring species; i.e. they did not restrict smaller, supposedly poorer competitors, from growing and reproducing close by. Taken together, these results provide no support for a size-advantage in competition restricting local species richness or the ability of small species to coexist and successfully reproduce in the immediate neighbourhood of a large species. PMID:24349177

Schamp, Brandon S.; Aarssen, Lonnie W.; Wight, Stephanie

2013-01-01

181

Invasive Plant Species: Inventory, Mapping, and Monitoring - A National Strategy  

USGS Publications Warehouse

America is under siege by invasive species of plants and animals, and by diseases. The current environmental, economic, and health-related costs of invasive species could exceed $138 billion per year-more than all other natural disasters combined. Notorious examples include West Nile virus, Dutch elm disease, chestnut blight, and purple loose- strife in the Northeast; kudzu, Brazilian peppertree, water hyacinth, nutria, and fire ants in the Southeast; zebra mussels, leafy spurge, and Asian long-horn beetles in the Midwest; salt cedar, Russian olive, and Africanized bees in the Southwest; yellow star thistle, European wild oats, oak wilt disease, Asian clams, and white pine blister rust in California; cheatgrass, various knapweeds, and thistles in the Great Basin; whirling disease of salmonids in the Northwest; hundreds of invasive species from microbes to mammals in Hawaii; and the brown tree snake in Guam. Thousands of species from other countries are introduced intentionally or accidentally into the United States each year. Based on past experience, 10-15 percent can be expected to establish free-living populations and about 1 percent can be expected to cause significant impacts to ecosystems, native species, economic productivity, and (or) human health.

Ludke, J. Larry; D'Erchia, Frank; Coffelt, Jan; Hanson, Leanne

2002-01-01

182

Plant species, atmospheric CO 2 and soil N interactively or additively control C allocation within plant-soil systems  

Microsoft Academic Search

Two plant species, Medicago truncatula (legume) and Avena sativa (non-legume), were grown in low-or high-N soils under two CO2 concentrations to test the hypothesis whether C allocation within plant-soil system is interactively or additively controlled\\u000a by soil N and atmospheric CO2 is dependent upon plant species. The results showed the interaction between plant species and soil N had a significant

Shenglei Fu; Ferris Howard

2006-01-01

183

REMOTE DETECTION OF INVASSIVE AND OPPORTUNISTIC PLANT SPECIES IN GREAT LAKES COASTAL WETLANDS  

EPA Science Inventory

Invasive and opportunistic plant species have been associated with wetland disturbance. Increases in the abundance of plant species such as common reed (Phragmites australis) in coastal Great Lakes wetlands are hypothesized to occur with shifts toward drier hydrologic regimes, fr...

184

REMOTE DETENTION OF INVASIVE AND OPPORTUNISTIC PLANT SPECIES IN GREAT LAKES COASTAL WETLANDS  

EPA Science Inventory

Invasive and opportunistic plant species have been associated with wetland disturbance. Increases in the abundance of plant species such as common reed (Phragmites australis) in coastal Great Lakes wetlands are hypothesized to occur with shifts toward drier hydrologic regimes, fr...

185

Genetic control of invasive plants species using selfish genetic elements  

PubMed Central

Invasive plants cause substantial environmental damage and economic loss. Here, we explore the possibility that a selfish genetic element found in plants called cytoplasmic male sterility (CMS) could be exploited for weed control. CMS is caused by mutations in the mitochondrial genome that sterilize male reproductive organs. We developed an analytical model and a spatial simulation to assess the use of CMS alleles to manage weed populations. Specifically, we examined how fertility, selfing, pollen limitation and dispersal influenced extinction rate and time until extinction in populations where CMS arises. We found that the introduction of a CMS allele can cause rapid population extinction, but only under a restricted set of conditions. Both models suggest that the CMS strategy will be appropriate for species where pollen limitation is negligible, inbreeding depression is high and the fertility advantage of females over hermaphrodites is substantial. In general, spatial structure did not have a strong influence on the simulation outcome, although low pollen dispersal and intermediate levels of seed dispersal tended to reduce population extinction rates. Given these results, the introduction of CMS alleles into a population of invasive plants probably represents an effective control method for only a select number of species.

Hodgins, Kathryn A; Rieseberg, Loren; Otto, Sarah P

2009-01-01

186

[Psychoactive plant species--actual list of plants prohibited in Poland].  

PubMed

According to the Act on Counteracting Drug Addiction (20-th of March, 2009, Dz. U. Nr 63 poz. 520.) the list of federally prohibited plants in Poland was expanded to include 16 new species. Until that time the only illegal plant materials were cannabis, papaver, coca and most of their products. The actual list of herbal narcotics includes species which significantly influence on the central nervous system work but which are rarely described in the national literature. The plants usually come from distant places, where--among primeval cultures--are used for ritual purposes. In our civilization the plants are usually used experimentally, recreationally or to gain particular narcotic effects. The results of the consumption vary: they can be specific or less typical, imitate other substances intake, mental disorders or different pathological states. The plant active substances can interact with other medicaments, be toxic to internal organs, cause serious threat to health or even death. This article describes the sixteen plant species, which are now prohibited in Poland, their biochemical ingredients and their influence on the human organism. PMID:23885543

Simonienko, Katarzyna; Waszkiewicz, Napoleon; Szulc, Agata

2013-01-01

187

Reactive oxygen species generation and signaling in plants  

PubMed Central

The introduction of molecular oxygen into the atmosphere was accompanied by the generation of reactive oxygen species (ROS) as side products of many biochemical reactions. ROS are permanently generated in plastids, peroxisomes, mitochiondria, the cytosol and the apoplast. Imbalance between ROS generation and safe detoxification generates oxidative stress and the accumulating ROS are harmful for the plants. On the other hand, specific ROS function as signaling molecules and activate signal transduction processes in response to various stresses. Here, we summarize the generation of ROS in the different cellular compartments and the signaling processes which are induced by ROS. PMID:23072988

Tripathy, Baishnab Charan; Oelmuller, Ralf

2012-01-01

188

Does resource availability, resource heterogeneity or species turnover mediate changes in plant species richness in grazed grasslands?  

PubMed

Grazing by large ungulates often increases plant species richness in grasslands of moderate to high productivity. In a mesic North American grassland with and without the presence of bison ( Bos bison), a native ungulate grazer, three non-exclusive hypotheses for increased plant species richness in grazed grasslands were evaluated: (1) bison grazing enhances levels of resource (light and N) availability, enabling species that depend on higher resource availability to co-occur; (2) spatial heterogeneity in resource availability is enhanced by bison, enabling coexistence of a greater number of plant species; (3) increased species turnover (i.e. increased species colonization and establishment) in grazed grassland is associated with enhanced plant species richness. We measured availability and spatial heterogeneity in light, water and N, and calculated species turnover from long-term data in grazed and ungrazed sites in a North American tallgrass prairie. Both regression and path analyses were performed to evaluate the potential of the three hypothesized mechanisms to explain observed patterns of plant species richness under field conditions. Experimental grazing by bison increased plant species richness by 25% over an 8-year period. Neither heterogeneity nor absolute levels of soil water or available N were related to patterns of species richness in grazed and ungrazed sites. However, high spatial heterogeneity in light and higher rates of species turnover were both strongly related to increases in plant species richness in grazed areas. This suggests that creation of a mosaic of patches with high and low biomass (the primary determinant of light availability in mesic grasslands) and promotion of a dynamic species pool are the most important mechanisms by which grazers affect species richness in high productivity grasslands. PMID:12955488

Bakker, C; Blair, J M; Knapp, A K

2003-11-01

189

Antimicrobial potentials of some plant species of the Bignoniaceae family.  

PubMed

The methanol extracts of the leaves and stem bark of four Bignoniaceae plants Jacaranda mimosifolia D. Dol., Tecoma stans Linn., Tabebuia rosea (Bertol) D.C., and Crescentia cujete Linn. were studied for their antimicrobial activity using a wide range of Gram-positive and Gram-negative bacteria and fungi. Extracts of both the leaves and stem bark of majority of plant species studied showed variable but remarkable broad spectrum antimicrobial activity. However, methanol extracts of Tecoma stans leaves was found to be effective against only Candida albicans at the concentrations employed. It was observed that the extracts of stem bark generally showed better antimicrobial activity than those of the leaves and some organisms were selectively more sensitive to the extracts than others. Preliminary phytochemical screening of these plants revealed the presence of tannins, flavonoids, alkaloids, quinones and traces of saponins. The antimicrobial activity observed are discussed in relation to the chemical constituents reportedly isolated from these plants and their traditional uses. PMID:7604753

Binutu, O A; Lajubutu, B A

1994-09-01

190

Role of fine roots in the plant-induced weathering of andesite for several plant species  

Microsoft Academic Search

The present work aims at providing experimental evidence for weathering as a direct consequence of plant physiology, and the importance of the proximity of fine roots to rock in the weathering process. Discussion is based on the release of different elements from andesite rock particles by the three crop species: rice, maize, and soybean. We designed two types of hydroponic

AKTER MEHERUNA; TASUKU AKAGI

2006-01-01

191

Does resource availability, resource heterogeneity or species turnover mediate changes in plant species richness in grazed grasslands?  

Microsoft Academic Search

Grazing by large ungulates often increases plant species richness in grasslands of moderate to high productivity. In a mesic North American grassland with and without the presence of bison ( Bos bison), a native ungulate grazer, three non-exclusive hypotheses for increased plant species richness in grazed grasslands were evaluated: (1) bison grazing enhances levels of resource (light and N) availability,

C. Bakker; J. M. Blair; A. K. Knapp

2003-01-01

192

Plant mortality varies with arbuscular mycorrhizal fungal species identities in a self-thinning population  

PubMed Central

Because arbuscular mycorrhizal fungal (AMF) species differ in stimulating the growth of particular host plant species, AMF species may vary in their effects on plant intra-specific competition and the self-thinning process. We tested this hypothesis using a microcosm experiment with Medicago sativa L. as a model plant population and four AMF species. Our results showed that the AMF species Glomus diaphanum stimulated host plant growth more than the other three AMF species did when the plants were grown individually. Glomus diaphanum also induced the highest rate of mortality in the self-thinning plant populations. We also found a positive correlation between mortality and growth response to colonization. Our results demonstrate that AMF species can affect plant mortality and the self-thinning process by affecting plant growth differently. PMID:21147829

Zhang, Qian; Tang, Jianjun; Chen, Xin

2011-01-01

193

Molecular Cloning and Bioinformatics Analysis of a New Plasma Membrane Na+/H+ Antiporter Gene from the Halophyte Kosteletzkya virginica  

PubMed Central

A new plasma membrane Na+/H+ antiporter gene (named as KvSOS1) was cloned from the halophyte Kosteletzkya virginica by reverse-transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) technology, which is a homologue of SOS1 (salt overly sensitive 1). The full-length cDNA is 3850?bp and contains an open reading frame (ORF) encoding a protein of 1147 amino acids with a molecular weight of 127.56?kDa and a theoretical pI of 6.18. Bioinformatics analysis indicated that the deduced protein appears to be a transmembrane protein with 12 transmembrane domains at the N-terminal region and a long hydrophilic tail in cytoplasm at its C-terminal region and shares 72–82% identity at the peptide level with other plant plasma membrane Na+/H+ antiporters. PMID:25093196

Wang, Hongyan; Tang, Xiaoli; Shao, Chuyang; Shao, Hongbo; Wang, Honglei

2014-01-01

194

Spatial aggregation facilitates coexistence and diversity of wild plant species in field margins  

Microsoft Academic Search

European agri-environment schemes encourage farmers to establish sown field margin strips to protect and enhance wild plant diversity. However, plant diversity in such wild plant sowings based on seed mixtures is often low due to the high competitiveness of few, common species. Here we analysed whether intraspecific aggregation could enhance the performance of less competitive species, and how plant performance

Birte Eleen Wassmuth; Peter Stoll; Teja Tscharntke; Carsten Thies

2009-01-01

195

Covariation and composition of arthropod species across plant genotypes of evening primrose, Oenothera biennis  

Microsoft Academic Search

Genetic variation in plants has broad implications for both the ecology and evolution of species interactions. We addressed how a diverse community of arthropod species covary in abundance among plant genotypes of a native herbaceous plant (Oenothera biennis ), and if these effects scale-up to shape the composition, diversity, and total abundance of arthropods over the entire lifetime of plants

Marc T. J. Johnson; Anurag A. Agrawal

2007-01-01

196

Plant species richness, elevated CO2, and atmospheric nitrogen deposition alter soil microbial community  

E-print Network

soil microbial community composition and function in a field experiment in which plant communitiesPlant species richness, elevated CO2, and atmospheric nitrogen deposition alter soil microbial plant assemblages, it is plausible that heterotrophic microbial communities would experience greater

Minnesota, University of

197

A Hydroponic Study of Heavy Metal Uptake by Selected Marsh Plant Species.  

National Technical Information Service (NTIS)

Eight marsh plants were grown in chemically controlled hydroponic solutions containing three concentrations of heavy metals to evluate the ability of each plant species to take up and accumulate heavy metals. The marsh plants studies were Cyperus esculent...

C. R. Lee, T. C. Sturgis, M. C. Landin

1976-01-01

198

Duck productivity in restored species-rich native and species-poor non-native plantings.  

PubMed

Conservation efforts to increase duck production have led the United States Fish and Wildlife Service to restore grasslands with multi-species (3-5) mixtures of introduced cool season vegetation often termed dense nesting cover (DNC). The effectiveness of DNC to increase duck production has been variable, and maintenance of the cover type is expensive. In an effort to decrease the financial and ecological costs (increased carbon emissions from plowing and reseeding) of maintaining DNC and provide a long-term, resilient cover that will support a diversity of grassland fauna, restoration of multi-species (16-32) plantings of native plants has been explored. We investigated the vegetation characteristics, nesting density and nest survival between the 2 aforementioned cover types in the Prairie Pothole Region of North Dakota, USA from 2010-2011 to see if restored-native plantings provide similar benefits to nesting hens as DNC. We searched 14 fields (7 DNC, 271 ha; and 7 restored native, 230 ha) locating 3384 nests (1215 in restored-native vegetation and 2169 in DNC) in 2010-2011. Nest survival was similar between cover types in 2010, while DNC had greater survival than native plantings in 2011. Densities of nests adjusted for detection probability were not different between cover types in either year. We found no structural difference in vegetation between cover types in 2010; however, a difference was detected during the late sampling period in 2011 with DNC having deeper litter and taller vegetation. Our results indicate restored-native plantings are able to support similar nesting density as DNC; however, nest survival is more stable between years in DNC. It appears the annual variation in security between cover types goes undetected by hens as hens selected cover types at similar levels both years. PMID:23840898

Haffele, Ryan D; Eichholz, Michael W; Dixon, Cami S

2013-01-01

199

The SbSOS1 gene from the extreme halophyte Salicornia brachiata enhances Na+ loading in xylem and confers salt tolerance in transgenic tobacco  

PubMed Central

Background Soil salinity adversely affects plant growth and development and disturbs intracellular ion homeostasis resulting cellular toxicity. The Salt Overly Sensitive 1 (SOS1) gene encodes a plasma membrane Na+/H+ antiporter that plays an important role in imparting salt stress tolerance to plants. Here, we report the cloning and characterisation of the SbSOS1 gene from Salicornia brachiata, an extreme halophyte. Results The SbSOS1 gene is 3774 bp long and encodes a protein of 1159 amino acids. SbSOS1 exhibited a greater level of constitutive expression in roots than in shoots and was further increased by salt stress. Overexpressing the S. brachiata SbSOS1 gene in tobacco conferred high salt tolerance, promoted seed germination and increased root length, shoot length, leaf area, fresh weight, dry weight, relative water content (RWC), chlorophyll, K+/Na+ ratio, membrane stability index, soluble sugar, proline and amino acid content relative to wild type (WT) plants. Transgenic plants exhibited reductions in electrolyte leakage, reactive oxygen species (ROS) and MDA content in response to salt stress, which probably occurred because of reduced cytosolic Na+ content and oxidative damage. At higher salt stress, transgenic tobacco plants exhibited reduced Na+ content in root and leaf and higher concentrations in stem and xylem sap relative to WT, which suggests a role of SbSOS1 in Na+ loading to xylem from root and leaf tissues. Transgenic lines also showed increased K+ and Ca2+ content in root tissue compared to WT, which reflect that SbSOS1 indirectly affects the other transporters activity. Conclusions Overexpression of SbSOS1 in tobacco conferred a high degree of salt tolerance, enhanced plant growth and altered physiological and biochemical parameters in response to salt stress. In addition to Na+ efflux outside the plasma membrane, SbSOS1 also helps to maintain variable Na+ content in different organs and also affect the other transporters activity indirectly. These results broaden the role of SbSOS1 in planta and suggest that this gene could be used to develop salt-tolerant transgenic crops. PMID:23057782

2012-01-01

200

Plant Functional Diversity and Species Diversity in the Mongolian Steppe  

PubMed Central

Background The Mongolian steppe is one of the most important grasslands in the world but suffers from aridization and damage from anthropogenic activities. Understanding structure and function of this community is important for the ecological conservation, but has seldom been investigated. Methodology/Principal Findings In this study, a total of 324 quadrats located on the three main types of Mongolian steppes were surveyed. Early-season perennial forbs (37% of total importance value), late-season annual forbs (33%) and late-season perennial forbs (44%) were dominant in meadow, typical and desert steppes, respectively. Species richness, diversity and plant functional type (PFT) richness decreased from the meadow, via typical to desert steppes, but evenness increased; PFT diversity in the desert and meadow steppes was higher than that in typical steppe. However, above-ground net primary productivity (ANPP) was far lower in desert steppe than in the other two steppes. In addition, the slope of the relationship between species richness and PFT richness increased from the meadow, via typical to desert steppes. Similarly, with an increase in species diversity, PFT diversity increased more quickly in both the desert and typical steppes than that in meadow steppe. Random resampling suggested that this coordination was partly due to a sampling effect of diversity. Conclusions/Significance These results indicate that desert steppe should be strictly protected because of its limited functional redundancy, which its ecological functioning is sensitive to species loss. In contrast, despite high potential forage production shared by the meadow and typical steppes, management of these two types of steppes should be different: meadow steppe should be preserved due to its higher conservation value characterized by more species redundancy and higher spatial heterogeneity, while typical steppe could be utilized moderately because its dominant grass genus Stipa is resistant to herbivory and drought. PMID:24116233

Liu, Guofang; Xie, Xiufang; Ye, Duo; Ye, Xuehua; Tuvshintogtokh, Indree; Mandakh, Bayart; Huang, Zhenying; Dong, Ming

2013-01-01

201

Cross-species translocation of mRNA from host plants into the parasitic plant dodder.  

PubMed

An intriguing new paradigm in plant biology is that systemically mobile mRNAs play a role in coordinating development. In this process, specific mRNAs are loaded into the phloem transport stream for translocation to distant tissues, where they may impact on developmental processes. However, despite its potential significance for plant growth regulation, mRNA trafficking remains poorly understood and challenging to study. Here, we show that phloem-mobile mRNAs can also traffic between widely divergent species from a host to the plant parasite lespedeza dodder (Cuscuta pentagona Engelm.). Reverse transcription-polymerase chain reaction and microarray analysis were used to detect specific tomato (Lycopersicon esculentum Mill.) transcripts in dodder grown on tomato that were not present in control dodder grown on other host species. Foreign transcripts included LeGAI, which has previously been shown to be translocated in the phloem, as well as nine other transcripts not reported to be mobile. Dodders are parasitic plants that obtain resources by drawing from the phloem of a host plant and have joint plasmodesmata with host cortical cells. Although viruses are known to move between dodder and its hosts, translocation of endogenous plant mRNA has not been reported. These results point to a potentially new level of interspecies communication, and raise questions about the ability of parasites to recognize, use, and respond to transcripts acquired from their hosts. PMID:17189329

Roney, Jeannine K; Khatibi, Piyum A; Westwood, James H

2007-02-01

202

Status of endangered and threatened plant species on Nevada Test Site: a survey. Part 2. Threatened species  

Microsoft Academic Search

This is the second of a two-part study of plant species on the Nevada Test Site (NTS) that are listed as possibly threatened or endangered by the U.S. Fish and Wildlife Service (FWS). This study was undertaken as a response by DOE to comply with the Endangered Species Act of 1973 (the Act). Part 1 treated species listed under terms

W. A. Rhoads; S. A. Cochrane; M. P. Williams

1978-01-01

203

Optical Parameters of Leaves of 30 Plant Species 1  

PubMed Central

Optical parameters (absorption coefficient k, infinite reflectance R?, scattering coefficient 8) are tabulated for seven wavelengths and analyzed for statistical differences for 30 plant species. The wavelengths are: 550 nm (green reflectance peak), 650 nm (chlorophyll absorption band), 850 nm (infrared reflectance plateau), 1450 nm (water absorption band), 1650 nm (reflectance peak following water absorption band at 1450 nm), 1950 nm (water absorption band), and 2200 nm (reflectance peak following water absorption band at 1950 nm). Thick, complex dorsiventral (bifacial mesophyll) leaves such as rubber plant, begonia, sedum, and privet had lower R? values than thinner, less complex dorsiventral leaves (i.e., soybean, peach, bean, rose) or essentially centric (undifferentiated mesophyll) sorghum and corn leaves. Infinite reflectance was negatively correlated with leaf thickness (?0.734**). Thick, complex dorsiventral leaves (crinum, oleander, privet, rubber plant, sedum) had higher (p 0.01) k values than thinner, less complex dorsiventral leaves (i.e., soybean, rose, peach) or essentially centric sorghum, sugarcane, and corn leaves. A coefficient of 0.718** was obtained for the correlation of k values with leaf thickness values. Complex dorsiventral oleander, orange, and crinum leaves had higher (p 0.01) 8 values than less complex dorsiventral (i.e., onion, begonia, banana) or centric leaves (i.e., corn and sugarcane). The scattering coefficient was not correlated with leaf thickness. PMID:16658499

Gausman, H. W.; Allen, W. A.

1973-01-01

204

Plant species used in traditional smallholder dairy processing in East Shoa, Ethiopia.  

PubMed

Plant species used in traditional dairy processing were studied in three districts (Bosset, Ada, and Gimbichu) in Eastern Shoa, Ethiopia, from October 2007 to March 2008. A total of 300 smallholders were interviewed using semi-structured questionnaires, and three focus group discussions were conducted, followed by plants specimen collection and identification. A total of 36 plant species, falling under 24 plant families, were identified. Nearly half of the identified plant species had more than one use types. Eleven plant species were/are used for washing (scrubbing) dairy utensils, ten plant species for smoking dairy utensils, 12 plant species in butter making, 15 plant species in ghee making, and five plant species for packaging (wrapping) butter and cheese. The plant species that had the highest overall citations from each use category were Ocimum hardiense, Olea europaea subspecies africana, Trachyspermum copticum, Curcuma longa, and Croton macrostachyus. The plant species used in the three study districts, representing different agro ecologies, showed some similarities, but levels of uses differed significantly (P?

Mekonnen, Hailemariam; Lemma, A

2011-04-01

205

Arabidopsis Species Hybrids in the Study of Species Differences and Evolution of Amphiploidy in Plants1  

PubMed Central

It is estimated that 5 million years of evolution separate Arabidopsis thaliana from its close relative Arabidopsis lyrata. The two taxa differ by many characteristics, and together they exemplify the differentiation of angiosperms into self-fertilizing and cross-fertilizing species as well as annual and perennial species. Despite their disparate life histories, the two species can be crossed to produce viable and vigorous hybrids exhibiting heterotic effects. Although pollen sterile, the hybrids produce viable ovules and were used as female parent in backcrosses to both parental species. The resulting backcross plants exhibited transgressive variation for a number of interesting developmental and growth traits as well as negative nuclear/cytoplasmic interactions. Moreover, the genesis of a fertile amphidiploid neospecies, apparently by spontaneous somatic doubling in an interspecific hybrid, was observed in the laboratory. The mechanisms responsible for the generation of amphiploids and the subsequent evolution of amphiploid genomes can now be studied through direct observation using the large arsenal of molecular tools available for Arabidopsis. PMID:11115878

Nasrallah, Mikhail E.; Yogeeswaran, Krithika; Snyder, Stephen; Nasrallah, June B.

2000-01-01

206

Arthropod assemblages on native and nonnative plant species of a coastal reserve in California.  

PubMed

Biological invasions by nonnative plant species are a widespread phenomenon. Many studies have shown strong ecological impacts of plant invasions on native plant communities and ecosystem processes. Far fewer studies have examined effects on associated animal communities. From the perspective of a reserve's land management, I addressed the question of whether arthropod assemblages on two nonnative plant species of concern were impoverished compared with those assemblages associated with two predominant native plant species of that reserve. If the nonnative plant species, Conium maculatum L., and Phalaris aquatica L., supported highly depauperate arthropod assemblages compared with the native plant species, Baccharis pilularis De Candolle and Leymus triticoides (Buckley) Pilger, this finding would provide additional support for prioritizing removal of nonnatives and restoration of natives. I assessed invertebrate assemblages at the taxonomic levels of arthropod orders, Coleoptera families, and Formicidae species, using univariate analyses to examine community attributes (richness and abundance) and multivariate techniques to assess arthropod assemblage community composition differences among plant species. Arthropod richness estimates by taxonomic level between native and nonnative vegetation showed varying results. Overall, arthropod richness of the selected nonnative plants, examined at higher taxonomic resolution, was not necessarily less diverse than two of common native plants found on the reserve, although differences were found among plant species. Impacts of certain nonnative plant species on arthropod assemblages may be more difficult to elucidate than those impacts shown on native plants and ecosystem processes. PMID:20550788

Fork, Susanne K

2010-06-01

207

The predominance of inorganic arsenic species in plants from Yellowknife, Northwest Territories, Canada  

SciTech Connect

Elevated levels of arsenic in Yellowknife, NWT, Canada, from historic and recent gold mine operations, are of increasing concern to Yellowknife residents. The study of arsenic in Yellowknife plants is a part of ongoing bioavailability and food chain research. A variety of plants from Yellowknife were analyzed for total arsenic and water soluble arsenic species. The plants included vascular plants and bryophytes (mosses). Total amounts of arsenic were greatest in mosses and varied greatly within specimens of the same plant species from different locations. Mostly inorganic arsenic species were extracted from plants using methanol/water (1:1). This result is very important from a toxicological point of view, since inorganic species are relatively toxic arsenic species. Small amounts of methylated arsenic species, as well as arsenosugars, were present in some plants. On average, greater than 50% of arsenic in these plants was not extracted; the chemical and toxicological characteristics of this fraction remain a topic for further study.

Koch, I.; Wang, L.; Ollson, C.A.; Cullen, W.R.; Reimer, K.J.

2000-01-01

208

Novel chemistry of invasive plants: exotic species have more unique metabolomic profiles than native congeners  

PubMed Central

It is often assumed that exotic plants can become invasive when they possess novel secondary chemistry compared with native plants in the introduced range. Using untargeted metabolomic fingerprinting, we compared a broad range of metabolites of six successful exotic plant species and their native congeners of the family Asteraceae. Our results showed that plant chemistry is highly species-specific and diverse among both exotic and native species. Nonetheless, the exotic species had on average a higher total number of metabolites and more species-unique metabolites compared with their native congeners. Herbivory led to an overall increase in metabolites in all plant species. Generalist herbivore performance was lower on most of the exotic species compared with the native species. We conclude that high chemical diversity and large phytochemical uniqueness of the exotic species could be indicative of biological invasion potential. PMID:25077026

Macel, Mirka; de Vos, Ric C H; Jansen, Jeroen J; van der Putten, Wim H; van Dam, Nicole M

2014-01-01

209

Novel chemistry of invasive plants: exotic species have more unique metabolomic profiles than native congeners.  

PubMed

It is often assumed that exotic plants can become invasive when they possess novel secondary chemistry compared with native plants in the introduced range. Using untargeted metabolomic fingerprinting, we compared a broad range of metabolites of six successful exotic plant species and their native congeners of the family Asteraceae. Our results showed that plant chemistry is highly species-specific and diverse among both exotic and native species. Nonetheless, the exotic species had on average a higher total number of metabolites and more species-unique metabolites compared with their native congeners. Herbivory led to an overall increase in metabolites in all plant species. Generalist herbivore performance was lower on most of the exotic species compared with the native species. We conclude that high chemical diversity and large phytochemical uniqueness of the exotic species could be indicative of biological invasion potential. PMID:25077026

Macel, Mirka; de Vos, Ric C H; Jansen, Jeroen J; van der Putten, Wim H; van Dam, Nicole M

2014-07-01

210

Phytoaccumulation of trace elements by wetland plants: 3. Uptake and accumulation of ten trace elements by twelve plant species  

Microsoft Academic Search

Interest is increasing in using wetland plants in constructed wetlands to remove toxic elements from polluted wastewater. To identify those wetland plants that hyperaccumulate trace elements, 12 plant species were tested for their efficiency to bioconcentrate 10 potentially toxic trace elements including As, b, Cd, Cr, Cu, Pb, Mn, Hg, Ni, and Se. Individual plants were grown under carefully controlled

Jin-Hong Qian; Adel Zayed; Yong-Liang Zhu; Mei Yu; Norman Terry

1999-01-01

211

The Reduction of Amphibian Species Richness in the Presence of Non-Native Plants  

Microsoft Academic Search

Wetlands are critical habitat for many species, making their protection a priority for biodiversity conservation. However, these ecosystems are being degraded at substantial rates. One factor that can be particularly detrimental is the presence of non­ native plant species. Exotic species have been known to out compete native species, alter trophic interactions between native species and transform habitat structure. To

Kaitlyn Schott

2012-01-01

212

Positive Effects of Plant Genotypic and Species Diversity on Anti-Herbivore Defenses in a Tropical Tree Species  

PubMed Central

Despite increasing evidence that plant intra- and inter-specific diversity increases primary productivity, and that such effect may in turn cascade up to influence herbivores, there is little information about plant diversity effects on plant anti-herbivore defenses, the relative importance of different sources of plant diversity, and the mechanisms for such effects. For example, increased plant growth at high diversity may lead to reduced investment in defenses via growth-defense trade-offs. Alternatively, positive effects of plant diversity on plant growth may lead to increased herbivore abundance which in turn leads to a greater investment in plant defenses. The magnitude of trait variation underlying diversity effects is usually greater among species than among genotypes within a given species, so plant species diversity effects on resource use by producers as well as on higher trophic levels should be stronger than genotypic diversity effects. Here we compared the relative importance of plant genotypic and species diversity on anti-herbivore defenses and whether such effects are mediated indirectly via diversity effects on plant growth and/or herbivore damage. To this end, we performed a large-scale field experiment where we manipulated genotypic diversity of big-leaf mahogany (Swietenia macrophylla) and tree species diversity, and measured effects on mahogany growth, damage by the stem-boring specialist caterpillar Hypsipyla grandella, and defensive traits (polyphenolics and condensed tannins in stem and leaves). We found that both forms of plant diversity had positive effects on stem (but not leaf) defenses. However, neither source of diversity influenced mahogany growth, and diversity effects on defenses were not mediated by either growth-defense trade-offs or changes in stem-borer damage. Although the mechanism(s) of diversity effects on plant defenses are yet to be determined, our study is one of the few to test for and show producer diversity effects on plant chemical defenses. PMID:25141305

Moreira, Xoaquin; Abdala-Roberts, Luis; Parra-Tabla, Victor; Mooney, Kailen A.

2014-01-01

213

Positive effects of plant genotypic and species diversity on anti-herbivore defenses in a tropical tree species.  

PubMed

Despite increasing evidence that plant intra- and inter-specific diversity increases primary productivity, and that such effect may in turn cascade up to influence herbivores, there is little information about plant diversity effects on plant anti-herbivore defenses, the relative importance of different sources of plant diversity, and the mechanisms for such effects. For example, increased plant growth at high diversity may lead to reduced investment in defenses via growth-defense trade-offs. Alternatively, positive effects of plant diversity on plant growth may lead to increased herbivore abundance which in turn leads to a greater investment in plant defenses. The magnitude of trait variation underlying diversity effects is usually greater among species than among genotypes within a given species, so plant species diversity effects on resource use by producers as well as on higher trophic levels should be stronger than genotypic diversity effects. Here we compared the relative importance of plant genotypic and species diversity on anti-herbivore defenses and whether such effects are mediated indirectly via diversity effects on plant growth and/or herbivore damage. To this end, we performed a large-scale field experiment where we manipulated genotypic diversity of big-leaf mahogany (Swietenia macrophylla) and tree species diversity, and measured effects on mahogany growth, damage by the stem-boring specialist caterpillar Hypsipyla grandella, and defensive traits (polyphenolics and condensed tannins in stem and leaves). We found that both forms of plant diversity had positive effects on stem (but not leaf) defenses. However, neither source of diversity influenced mahogany growth, and diversity effects on defenses were not mediated by either growth-defense trade-offs or changes in stem-borer damage. Although the mechanism(s) of diversity effects on plant defenses are yet to be determined, our study is one of the few to test for and show producer diversity effects on plant chemical defenses. PMID:25141305

Moreira, Xoaquín; Abdala-Roberts, Luis; Parra-Tabla, Víctor; Mooney, Kailen A

2014-01-01

214

Productivity is a poor predictor of plant species richness  

USGS Publications Warehouse

For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent meta-analyses questioned the generality of hump-shaped patterns, these syntheses have been criticized for failing to account for methodological differences among studies. We addressed such concerns by conducting standardized sampling in 48 herbaceous-dominated plant communities on five continents. We found no clear relationship between productivity and fine-scale (meters-2) richness within sites, within regions, or across the globe. Ecologists should focus on fresh, mechanistic approaches to understanding the multivariate links between productivity an

Adler, Peter B.; Seabloom, Eric W.; Borer, Elizabeth T.; Hillebrand, Helmut; Hautier, Yann; Hector, Andy; Harpole, W. Stanley; O'Halloran, Lydia R.; Grace, James B.; Anderson, T. Michael; Bakker, Jonathan D.; Biederman, Lori A.; Brown, Cynthia S.; Buckley, Yvonne M.; Calabrese, Laura B.; Chu, Cheng-Jin; Cleland, Elsa E.; Collins, Scott L.; Cottingham, Kathryn L.; Crawley, Michael J.; Damschen, Ellen I.; Davies, Kendi F.; DeCrappeo, Nicole M.; Fay, Philip A.; Firn, Jennifer; Frater, Paul; Gasarch, Eve I.; Gruner, Daneil S.; Hagenah, Nicole; Lambers, Janneke Hille Ris; Humphries, Hope; Jin, Virginia L.; Kay, Adam D.; Kirkman, Kevin P.; Klein, Julia A.; Knops, Johannes M.H.; La Pierre, Kimberly J.; Lambrinos, John G.; Li, Wei; MacDougall, Andrew S.; McCulley, Rebecca L.; Melbourne, Brett A.; Mitchell, Charles E.; Moore, Joslin L.; Morgan, John W.; Mortensen, Brent; Orrock, John L.; Prober, Suzanne M.; Pyke, David A.; Risch, Anita C.; Schuetz, Martin; Smith, Melinda D.; Stevens, Carly J.; Sullivan, Lauren L.; Wang, Gang; Wragg, Peter D.; Wright, Justin P.; Yang, Louie H.

2011-01-01

215

The evolution of cultivated plant species: classical plant breeding versus genetic engineering  

Microsoft Academic Search

Agriculture is the most intensive form of environmental exploitation performed by mankind. It involves replacing the natural\\u000a ecosystem with an artificial plant community comprising one or more crop species, and weeds can invade the cleared land. Initially,\\u000a the adoption of agriculture did not necessarily imply an improvement in standard of living (there is, in fact, evidence to\\u000a the contrary), but

Hakan Ulukan

2009-01-01

216

Plant species invasions along the latitudinal gradient in the United States  

USGS Publications Warehouse

It has been long established that the richness of vascular plant species and many animal taxa decreases with increasing latitude, a pattern that very generally follows declines in actual and potential evapotranspiration, solar radiation, temperature, and thus, total productivity. Using county-level data on vascular plants from the United States (3000 counties in the conterminous 48 states), we used the Akaike Information Criterion (AIC) to evaluate competing models predicting native and nonnative plant species density (number of species per square kilometer in a county) from various combinations of biotic variables (e.g., native bird species density, vegetation carbon, normalized difference vegetation index), environmental/topographic variables (elevation, variation in elevation, the number of land cover classes in the county; radiation, mean precipitation, actual evapotranspiration, and potential evapotranspiration), and human variables (human population density, crop-land, and percentage of disturbed lands in a county). We found no evidence of a latitudinal gradient for the density of native plant species and a significant, slightly positive latitudinal gradient for the density of nonnative plant species. We found stronger evidence of a significant, positive productivity gradient (vegetation carbon) for the density of native plant species and nonnative plant species. We found much stronger significant relationships when biotic, environmental/topographic, and human variables were used to predict native plant species density and nonnative plant species density. Biotic variables generally had far greater influence in multivariate models than human or environmental/topographic variables. Later, we found that the best, single, positive predictor of the density of nonnative plant species in a county was the density of native plant species in a county. While further study is needed, it may be that, while humans facilitate the initial establishment invasions of nonnative plant species, the spread and subsequent distributions of nonnative species are controlled largely by biotic and environmental factors.

Stohlgren, T.J.; Barnett, D.; Flather, C.; Kartesz, J.; Peterjohn, B.

2005-01-01

217

AN INDICATOR OF PLANT SPECIES RICHNESS OF SEMINATURAL HABITATS AND CROPS ON ARABLE FARMS  

Microsoft Academic Search

Indicator threshold values for conventional farms were defined based on the best 10% of the variation in species richness among farms. With appropriate farm management these targets could be achieved. In comparison to ditch banks, crops and sown field margin strips were relatively poor in plant species. The respective numbers of naturally occurring plant species found in crops and field

Astrid Manhoudt; Helias Udo de Haes; Geert de Snoo

218

Riparian zones as havens for exotic plant species in the central grasslands  

Microsoft Academic Search

In the Central Grasslands of the United States, we hypothesized that riparian zones high in soil fertility would contain more exotic plant species than upland areas of low soil fertility. Our alternate hypothesis was that riparian zones high in native plant species richness and cover would monopolize available resources and resist invasion by exotic species. We gathered nested-scale vegetation data

Thomas J. Stohlgren; Kelly A. Bull; Yuka Otsuki; Cynthia A. Villa; Michelle Lee

1998-01-01

219

Allelopathic effects of water extracts of Artemisia princeps var. orientalis on selected plant species  

Microsoft Academic Search

The allelopathic effects of wormwood plants (Artemisia princeps var.orientalis) and their possible phytotoxicity on receptor species were investigated. The aqueous extracts of mature leaf, stem, and root of wormwood plants caused significant inhibition in germination and decreased seedling elongation of receptor plants, whereas germination of some species was not inhibited by extracts of stems and roots. Dry weight growth was

Bong-Seop Kil; Kyeong Won Yun

1992-01-01

220

Ecophysiological differences among juvenile and reproductive plants of several woody species  

Microsoft Academic Search

Photosynthetic and water relations characteristics of small juvenile and large reproductive plants were investigated during one growing season for four woody species native to Red Butte Canyon, Utah, USA: Acer negundo, Artemisia tridentata, Chrysothamnus nauseosus, and Salix exigua. For all species, juvenile plants differed from reproductive plants in at least one of the following characters: water potential, stomatal conductance, photosynthetic

Lisa A. Donovan; James R. Ehleringer

1991-01-01

221

Comparison of relative antioxidant activities of British medicinal plant species in vitro  

Microsoft Academic Search

We have determined the relative levels of endogenous antioxidant activity in a range of British medicinal plant species (representative of a variety of plant families, selected on the basis of their widespread use in traditional herbal medicine), via competitive scavenging of the ABTS+ or O2? radicals in vitro. A number of plant species with appreciable levels (i.e. greater than or

David Mantle; Fadel Eddeb; Anne T. Pickering

2000-01-01

222

Comparative drought-resistance of seedlings of 28 species of co-occurring tropical woody plants  

Microsoft Academic Search

Quantifying plant drought resistance is important for understanding plant species' association to microhabitats with different soil moisture availability and their distribution along rainfall gradients, as well as for understanding the role of underlying morphological and physiological mechanisms. The effect of dry season drought on survival and leaf-area change of first year seedlings of 28 species of co-occurring woody tropical plants

Bettina M. J. Engelbrecht; Thomas A. Kursar

2003-01-01

223

American Journal of Botany 92(1): 1320. 2005. PLANT GENERALIZATION ON POLLINATORS: SPECIES  

E-print Network

13 American Journal of Botany 92(1): 13­20. 2005. PLANT GENERALIZATION ON POLLINATORS: SPECIES interest in the frequency and evolutionary consequences of generalization in plant­pollinator systems, little is known on whether plant generalization on pollinators actually is a species-level trait

Herrera, Carlos M.

224

OIKOS 100: 362372, 2003 Mycorrhizal species identity affects plant community structure and  

E-print Network

invasion success. Final aboveground and belowground phytomass were used to assess plant communityOIKOS 100: 362­372, 2003 Mycorrhizal species identity affects plant community structure. Mycorrhizal species identity affects plant community structure and invasion: a microcosm study. ­ Oikos 100

Bruns, Tom

225

Covariation and composition of arthropod species across plant genotypes of evening primrose, Oenothera biennis  

E-print Network

Covariation and composition of arthropod species across plant genotypes of evening primrose of arthropod species covary in abundance among plant genotypes of a native herbaceous plant (Oenothera biennis), and if these effects scale-up to shape the composition, diversity, and total abundance of arthropods over the entire

Agrawal, Anurag

226

Species-driven changes in nitrogen cycling can provide a mechanism for plant invasions  

PubMed Central

Traits that permit successful invasions have often seemed idiosyncratic, and the key biological traits identified vary widely among species. This fundamentally limits our ability to determine the invasion potential of a species. However, ultimately, successful invaders must have positive growth rates that longer term result in higher biomass accumulation than competing established species. In many terrestrial ecosystems nitrogen limits plant growth, and is a key factor determining productivity and the outcome of competition among species. Plant nitrogen use may provide a powerful framework to evaluate the invasive potential of a species in nitrogen-limiting ecosystems. Six mechanisms influence plant nitrogen use or acquisition: photosynthetic tissue allocation, photosynthetic nitrogen use efficiency, nitrogen fixation, nitrogen-leaching losses, gross nitrogen mineralization, and plant nitrogen residence time. Here we show that among these alternatives, the key mechanism allowing invasion for Pinus strobus into nitrogen limited grasslands was its higher nitrogen residence time. This higher nitrogen residence time created a positive feedback that redistributed nitrogen from the soil into the plant. This positive feedback allowed P. strobus to accumulate twice as much nitrogen in its tissues and four times as much nitrogen to photosynthetic tissues, as compared with other plant species. In turn, this larger leaf nitrogen pool increased total plant carbon gain of P. strobus two- to sevenfold as compared with other plant species. Thus our data illustrate that plant species can change internal ecosystem nitrogen cycling feedbacks and this mechanism can allow them to gain a competitive advantage over other plant species. PMID:19592506

Laungani, Ramesh; Knops, Johannes M. H.

2009-01-01

227

Changes in Semi-Arid Plant Species Associations along a Livestock Grazing Gradient  

PubMed Central

In semi-arid ecosystems, vegetation is heterogeneously distributed, with plant species often associating in patches. These associations between species are not constant, but depend on the particular response of each species to environmental factors. Here, we investigated how plant species associations change in response to livestock grazing in a semi-arid ecosystem, Cabo de Gata-Níjar Natural Park in South East Spain. We established linear point-intercept transects at four sites with different grazing intensity, and recorded all species at each point. We investigated plant associations by comparing the number of times that each pair of species occurred at the same spatial point (co-occurrences), with the expected number of times based on species abundances. We also assessed associations for each shrub and grass species by considering all their pairs of associations and for the whole plant community by considering all pairs of associations on each site. At all sites, the plant community had a negative pattern of association, with fewer co-occurrences than expected. Negative association in the plant community increased at maximum grazing intensity. Most species associated as expected, particularly grass species, and positive associations were most important at intermediate grazing intensities. No species changed its type of association along the grazing gradient. We conclude that in the present plant community, grazing-resistant species compete among themselves and segregate in space. Some shrub species act as refuges for grazing-sensitive species that benefit from being spatially associated with shrub species, particularly at intermediate grazing intensities where positive associations were highest. At high grazing intensity, these shrubs can no longer persist and positive associations decrease due to the disappearance of refuges. Spatial associations between plant species and their response to grazing help identify the factors that organize plant communities, and may contribute to improving management of semi-arid ecosystems. PMID:22792367

Saiz, Hugo; Alados, Concepcion L.

2012-01-01

228

Knowledge and Use Value of Plant Species in a Rarámuri Community: A Gender Perspective for Conservation  

Microsoft Academic Search

We used a quantitative ethnobotanical approach to analyze factors influencing the use value of plant species among men and\\u000a women of the Rarámuri people in Cuiteco, Chihuahua, Mexico. We constructed a use value index (UV) combining the use frequency\\u000a (U) and the quality perception (Q) of useful plant species by local people. We identified all plant species used by the

Andrés Camou-Guerrero; Victoria Reyes-García; Miguel Martínez-Ramos; Alejandro Casas

2008-01-01

229

Chromium Removal from Soil by Phytoremediation with Weed Plant Species in Thailand  

Microsoft Academic Search

The possibility of using phytoremediation with weed plant species in Thailand to remove chromium (Cr) from soil was investigated.\\u000a Six plant species, Cynodon dactylon, Pluchea indica, Phyllanthus reticulatus, Echinochloa colonum, Vetiveria nemoralis, and Amaranthus viridis, were chosen for their abilities to accumulate total chromium (TCr) at tanning industry sites. These plant species were studied\\u000a in pots at a nursery. Cynodon

Pantawat Sampanpanish; Wasant Pongsapich; Sutha Khaodhiar; Eakalak Khan

2006-01-01

230

Influence of N 2 -fixing Trifolium on plant species composition and biomass production in alpine tundra  

Microsoft Academic Search

Alpine Trifolium species have high rates of symbiotic N2-fixation which may influence the abundance and growth of plant species growing near them. The potential for facilitative\\u000a effects on plant abundance and growth in dry meadow alpine tundra of Niwot Ridge, Colo., characterized by low resource availability,\\u000a was investigated by measuring soil N, aboveground biomass production, and plant species composition in

Brian D. Thomas; William D. Bowman

1998-01-01

231

N 2 fixation in three perennial Trifolium species in experimental grasslands of varied plant species richness and composition  

Microsoft Academic Search

This study is the first to investigate quantitative effects of plant community composition and diversity on N2 fixation in legumes. N2 fixation in three perennial Trifolium species grown in field plots with varied number of neighbouring species was evaluated with the 15N natural abundance method (two field sites, several growing seasons, no N addition) and the isotope dilution method (one

Georg Carlsson; Cecilia Palmborg; Ari Jumpponen; Michael Scherer-Lorenzen; Peter Högberg; Kerstin Huss-Danell

2009-01-01

232

Divergent composition but similar function of soil food webs of individual plants: plant species and community effects.  

PubMed

Soils are extremely rich in biodiversity, and soil organisms play pivotal roles in supporting terrestrial life, but the role that individual plants and plant communities play in influencing the diversity and functioning of soil food webs remains highly debated. Plants, as primary producers and providers of resources to the soil food web, are of vital importance for the composition, structure, and functioning of soil communities. However, whether natural soil food webs that are completely open to immigration and emigration differ underneath individual plants remains unknown. In a biodiversity restoration experiment we first compared the soil nematode communities of 228 individual plants belonging to eight herbaceous species. We included grass, leguminous, and non-leguminous species. Each individual plant grew intermingled with other species, but all plant species had a different nematode community. Moreover, nematode communities were more similar when plant individuals were growing in the same as compared to different plant communities, and these effects were most apparent for the groups of bacterivorous, carnivorous, and omnivorous nematodes. Subsequently, we analyzed the composition, structure, and functioning of the complete soil food webs of 58 individual plants, belonging to two of the plant species, Lotus corniculatus (Fabaceae) and Plantago lanceolata (Plantaginaceae). We isolated and identified more than 150 taxa/groups of soil organisms. The soil community composition and structure of the entire food webs were influenced both by the species identity of the plant individual and the surrounding plant community. Unexpectedly, plant identity had the strongest effects on decomposing soil organisms, widely believed to be generalist feeders. In contrast, quantitative food web modeling showed that the composition of the plant community influenced nitrogen mineralization under individual plants, but that plant species identity did not affect nitrogen or carbon mineralization or food web stability. Hence, the composition and structure of entire soil food webs vary at the scale of individual plants and are strongly influenced by the species identity of the plant. However, the ecosystem functions these food webs provide are determined by the identity of the entire plant community. PMID:21058562

Bezemer, T M; Fountain, M T; Barea, J M; Christensen, S; Dekker, S C; Duyts, H; van Hal, R; Harvey, J A; Hedlund, K; Maraun, M; Mikola, J; Mladenov, A G; Robin, C; de Ruiter, P C; Scheu, S; Setälä, H; Smilauer, P; van der Putten, W H

2010-10-01

233

Performance of dryland and wetland plant species on extensive green roofs  

PubMed Central

Background and Aims Green roofs are constructed ecosystems where plants perform valuable services, ameliorating the urban environment through roof temperature reductions and stormwater interception. Plant species differ in functional characteristics that alter ecosystem properties. Plant performance research on extensive green roofs has so far indicated that species adapted to dry conditions perform optimally. However, in moist, humid climates, species typical of wetter soils might have advantages over dryland species. In this study, survival, growth and the performance of thermal and stormwater capture functions of three pairs of dryland and wetland plant species were quantified using an extensive modular green roof system. Methods Seedlings of all six species were germinated in a greenhouse and planted into green roof modules with 6 cm of growing medium. There were 34 treatments consisting of each species in monoculture and all combinations of wet- and dryland species in a randomized block design. Performance measures were survival, vegetation cover and roof surface temperature recorded for each module over two growing seasons, water loss (an estimate of evapotranspiration) in 2007, and albedo and water capture in 2008. Key Results Over two seasons, dryland plants performed better than wetland plants, and increasing the number of dryland species in mixtures tended to improve functioning, although there was no clear effect of species or habitat group diversity. All species had survival rates >75 % after the first winter; however, dryland species had much greater cover, an important indicator of green roof performance. Sibbaldiopsis tridentata was the top performing species in monoculture, and was included in the best treatments. Conclusions Although dryland species outperformed wetland species, planting extensive green roofs with both groups decreased performance only slightly, while increasing diversity and possibly habitat value. This study provides further evidence that plant composition and diversity can influence green roof functions. PMID:21292676

MacIvor, J. Scott; Ranalli, Melissa A.; Lundholm, Jeremy T.

2011-01-01

234

Pollinator-mediated impacts of the invasive plant species Lythrum salicaria on the native Decodon verticillatus .  

E-print Network

??Plant-pollinator interactions in invaded communities can range from facilitative to competitive, with the latter being most commonly observed. If invasive species can successfully integrate into… (more)

Da Silva, Elizabeth M

2013-01-01

235

Selenium Accumulation in Brassicaceae Plant Species and its Biotransfer to Insect Pollinators  

E-print Network

plants employ innate defenses such as secondary compounds to guard against herbivoreplant species known as hyperaccumulators that have evolved to use certain elements as a defense against herbivores (

Hladun, Kristen

2012-01-01

236

Differential herbivory tolerance of dominant and subordinate plant species along gradients of nutrient availability and competition  

Microsoft Academic Search

We tested whether differences in the herbivory tolerance of plant species is related to their abundance in grassland communities\\u000a and how herbivory and nutrient availability affect competitive balances among plant species through changes in their tolerance.\\u000a The experimental approach involved a simulated grazing treatment (clipping) of two competitive grass species (Arrhenatherum elatius and Holcus lanatus) and two subordinate forb species

Pejman Tahmasebi Kohyani; B. Bossuyt; D. Bonte; M. Hoffmann

237

Differential herbivory tolerance of dominant and subordinate plant species along gradients of nutrient availability and competition  

Microsoft Academic Search

We tested whether differences in the herbivory tolerance of plant species is related to their abundance in grassland communities\\u000a and how herbivory and nutrient availability affect competitive balances among plant species through changes in their tolerance.\\u000a The experimental approach involved a simulated grazing treatment (clipping) of two competitive grass species (Arrhenatherum elatius and Holcus lanatus) and two subordinate forb species

Pejman Tahmasebi Kohyani; B. Bossuyt; D. Bonte; M. Hoffmann

2009-01-01

238

Arbuscular mycorrhizal fungi species-specifically affect induced plant responses to a spider mite  

Microsoft Academic Search

It is widely recognized that arbuscular mycorrhizal fungi (AMF) improve plant growth and nutrient conditions, but their effects\\u000a can vary from negative to positive depending on AMF species. Since the performance of herbivorous arthropods varies with plant\\u000a quality, different AMF species should differently affect the density of herbivorous arthropods on plants and the herbivore-induced\\u000a plant responses. We examined the indirect

Takaaki Nishida; Noboru Katayama; Naoyuki Izumi; Takayuki Ohgushi

2010-01-01

239

Plant species identity surpasses species richness as a key driver of N(2)O emissions from grassland.  

PubMed

Grassland ecosystems worldwide not only provide many important ecosystem services but they also function as a major source of the greenhouse gas nitrous oxide (N2O), especially in response to nitrogen deposition by grazing animals. To explore the role of plants as mediators of these emissions, we tested whether and how N2O emissions are dependent on grass species richness and/or specific grass species composition in the absence and presence of urine deposition. We hypothesized that: (i) N2O emissions relate negatively to plant productivity; (ii) four-species mixtures have lower emissions than monocultures (as they are expected to be more productive); (iii) emissions are lowest in combinations of species with diverging root morphology and high root biomass; and (iv) the identity of the key species that reduce N2O emissions is dependent on urine deposition. We established monocultures and two- and four-species mixtures of common grass species with diverging functional traits: Lolium perenne L. (Lp), Festuca arundinacea Schreb. (Fa), Phleum pratense L. (Php) and Poa trivialis L. (Pt), and quantified N2O emissions for 42 days. We found no relation between plant species richness and N2O emissions. However, N2O emissions were significantly reduced in specific plant species combinations. In the absence of urine, plant communities of Fa+Php acted as a sink for N2O, whereas the monocultures of these species constituted a N2O source. With urine application Lp+Pt plant communities reduced (P < 0.001) N2O emissions by 44% compared to monocultures of Lp. Reductions in N2O emissions by species mixtures could be explained by total biomass productivity and by complementarity in root morphology. This study shows that plant species composition is a key component underlying N2O emissions from grassland ecosystems. Selection of specific grass species combinations in the context of the expected nitrogen deposition regimes may therefore provide a key for mitigation of N2O emissions. PMID:23939815

Abalos, Diego; De Deyn, Gerlinde B; Kuyper, Thomas W; Van Groenigen, Jan Willem

2014-01-01

240

Is the use-impact on native caatinga species in Brazil reduced by the high species richness of medicinal plants?  

PubMed

A study of the diversity of uses of medicinal plants and the traditional knowledge associated with the caatinga vegetation was undertaken in the semi-arid region of Pernambuco State, NE Brazil. We tested the utilitarian redundancy model (as an analogy to the ecological redundancy hypothesis) in evaluating the implications of the use of medicinal plants by rural communities to examine whether the presence of numerous species with analogous functions (identical therapeutic applications, for example) would reduce the use-impact on native species in the neighboring caatinga vegetation. Various techniques were used to collect information concerning medicinal plants and their applications from 19 residents considered "local specialists". The vegetation was sampled to determine the abundance of woody plants. Approximately 106 plants that fall into 67 local therapeutic categories were identified. Despite the fact that exotic species compose a significant fraction of the local medicinal flora, the native species represented the greatest percentage of local uses and indications. Amburana cearensis, Myracrodruon urundeuva, Anadenanthera colubrina, Sideroxylon obtusifolium, and Ziziphus joazeiro, for example, are highly sought after plants, and represent key species in terms of conservation and sustainable management. Our model of utilitarian redundancy has important consequences for testing ethnobotanical hypotheses, as well as for indicating strategies for biodiversity conservation. PMID:17616289

de Albuquerque, Ulysses Paulino; de Oliveira, Rosilane Ferreira

2007-08-15

241

Assessing vulnerability to invasion by nonnative plant species at multiple spatial scales.  

PubMed

Basic information on where nonnative plant species have successfully invaded is lacking. We assessed the vulnerability of 22 vegetation types (25 sets of four plots in nine study areas) to nonnative plant invasions in the north-central United States. In general, habitats with high native species richness were more heavily invaded than species-poor habitats, low-elevation areas were more invaded than high-elevation areas, and riparian zones were more invaded than nearby upland sites. For the 100 1000-m2 plots (across all vegetation types), 50% of the variation in nonnative species richness was explained by longitude, latitude, native plant species richness, soil total percentage nitrogen, and mean maximum July temperature (n = 100 plots; P < 0.001). At the vegetation-type scale (n = 25 sets of four 1000-m2 plots/type), 64% of the variation in nonnative species richness was explained by native plant species richness, elevation, and October to June precipitation (P < 0.001). The foliar cover of nonnative species (log) was strongly positively correlated with the nonnative species richness at the plot scale (r = 0.77, P < 0.001) and vegetation-type scale (r = 0.83, P < 0.001). We concluded that, at the vegetation-type and regional scales in the north-central United States, (1) vegetation types rich in native species are often highly vulnerable to invasion by nonnative plant species; (2) where several nonnative species become established, nonnative species cover can substantially increase; (3) the attributes that maintain high native plant species richness (high light, water, nitrogen, and temperatures) also help maintain nonnative plant species richness; and (4) more care must be taken to preserve native species diversity in highly vulnerable habitats. PMID:12071506

Stohlgren, Thomas J; Chong, Geneva W; Schell, Lisa D; Rimar, Kelly A; Otsuki, Yuka; Lee, Michelle; Kalkhan, Mohammed A; Villa, Cynthia A

2002-04-01

242

Risk assessment: Simultaneously prioritizing the control of invasive plant species and the conservation of rare plant species  

Microsoft Academic Search

Although the consequences of the homogenization of Earth’s flora and fauna are not well understood, experts agree that biological invasions pose hazards to rare species. As a result, there is a need for a systematic approach to assess risks from invasive species. The Relative Risk Model can be adapted to assess combinations of rare species, invasive species, and regions. It

Thaddeus K. Miller; Craig R. Allen; Wayne G. Landis; James W. Merchant

2010-01-01

243

Response of xylem-feeding leafhopper to host plant species and plant quality.  

PubMed

Carneocephala floridana, an oligophagous leafhopper that inhabits the salt marshes along the coasts of Florida, utilizesBorrichia frutescens andSalicornia virginica (both herbs) as primary summer hosts, but uses two grasses,Distichlis spicata andSpartina alterniflora, during the winter. We tested whether the seasonal patterns of abundance and apparent host-switching byCarneocephala are related to plant quality. In laboratory experiments, nymphs ofCarneocephala reared on nonfertilized control plants of the two herbs produced adults that were similar in size to field-collected insects. OnlyCarneocephala raised at the lowest densities onSpartina andDistichlis from the highest fertilizer treatments produced adults similar in body mass to those reared on nonfertilizedBorrichia andSalicornia. ForDistichlis, superior quality (high foliar nitrogen) plants were able to mitigate the negative effect of nymphal crowding on adult body mass. However, laboratory fertilization regimes produced an extremely high foliar nitrogen content in the two herbs and the organic acid concentration in the xylem fluid ofBorrichia, the only host species suitable for xylem fluid extraction, increased 2.5- to 3-fold. Total amino acid concentration in the xylem fluid of fertilizedBorrichia decreased compared to nonfertilized plants.Carneocephala demonstrated reduced feeding efficiencies on high nitrogenBorrichia. Our results suggest thatCarneocephala prefers, and performs better on, plants with high nitrogen content up to a threshold, beyond which high nitrogen levels result in reduced leafhopper feeding rates and assimilation efficiencies. PMID:24227575

Rossi, A M; Brodbeck, B V; Strong, D R

1996-04-01

244

Assaying Ornithine and Arginine Decarboxylases in Some Plant Species 1  

PubMed Central

A release of 14CO2 not related to ornithine decarboxylase activity was found in crude leaf extracts from Lycopersicon esculentum, Avena sativa, and especially from the pyrrolizidine alkaloid-bearing Heliotropium angiospermum when incubated with [1-14C]- or [U-14C]ornithine. The total 14CO2 produced was about 5- to 100-fold higher than that due to ornithine decarboxylase activities calculated from labeled putrescine (Put) found by thin-layer electrophoresis in the incubation mixtures. Partial purification with (NH4)2SO4 did not eliminate completely the interfering decarboxylation. When incubated with labeled arginine, a very significant 14CO2 release not related to arginine decarboxylase activity was observed only in extracts from H. angiospermum leaves, especially in Tris·HCl buffer. Under the assay conditions, these extracts exhibited oxidative degradation of added Put and agmatine (Agm) and also revealed a high arginase activity. Amino-guanidine at 0.1 to 0.2 millimolar prevented Put degradation and greatly decreased oxidative degradation of Agm; ornithine at 15 to 20 millimolar significantly inhibited arginase activity. A verification of the reliability of the standard 14CO2-based method by assessing labeled Put and/or Agm—formed in the presence of added aminoguanidine and/or ornithine when needed—is recommended especially when crude or semicrude plant extracts are assayed. When based on Put and/or Agm formed at 1.0 to 2.5 millimolar of substrate, the activities of ornithine decarboxylase and arginine decarboxylase in the youngest leaves of the tested species ranged between 1.1 and 3.6 and 1 and 1600 nanomoles per hour per gram fresh weight, respectively. The enzyme activities are discussed in relation to the biosynthesis of pyrrolizidine alkaloids. PMID:16664441

Birecka, Helena; Bitonti, Alan J.; McCann, Peter P.

1985-01-01

245

Predicting the Growth Interactions between Plants in Mixed Species Stands using a Simple Mechanistic Model  

Microsoft Academic Search

The Conductance model is a simple mechanistic model used to predict the growth of species in monoculture or mixtures from parameter values derived from plants grown in isolation. In contrast to many mechanistic models that require extensive parameterization, the Conductance model is able to capture the growth of a broad range of species using a few simplified assumptions regarding plant

S. E. Park; L. R. Benjamin; D. P. Aikman; A. R. Watkinson

2001-01-01

246

Quality over quantity: buffer strips can be improved with select native plant species.  

PubMed

Native plants attractive to beneficial insects may improve the value of buffer strips by increasing biodiversity and enhancing the delivery of insect-derived ecosystem services. In a 2-yr field experiment, we measured the response of insect communities across nine buffers that varied in plant diversity. We constructed buffers with plants commonly found in buffers of USDA-certified organic farms in Iowa (typically a single species), recommended for prairie reconstruction, or recommended for attracting beneficial insects. We hypothesized that the diversity and abundance of beneficial insects will be 1) greatest in buffers composed of diverse plant communities with continuous availability of floral resources, 2) intermediate in buffers with reduced species richness and availability of floral resources, and 3) lowest in buffers composed of a single species. We observed a significant positive relationship between the diversity and abundance of beneficial insects with plant community diversity and the number of flowers. More beneficial insects were collected in buffers composed of species selected for their attractiveness to beneficial insects than a community recommended for prairie restoration. These differences suggest 1) plant communities that dominate existing buffers are not optimal for attracting beneficial insects, 2) adding flowering perennial species could improve buffers as habitat for beneficial insects, 3) buffers can be optimized by intentionally combining the most attractive native species even at modest levels of plant diversity, and 4) plant communities recommended for prairie reconstruction may not contain the optimal species or density of the most attractive species necessary to support beneficial insects from multiple guilds. PMID:24763090

Gill, K A; Cox, R; O'Neal, M E

2014-04-01

247

The impacts of individual plant species on rhizosphere microbial communities in soils of different fertility  

Microsoft Academic Search

To investigate the effects of individual plant species on microbial community properties in soils of differing fertility, a microcosm experiment was carried out using plant species representative of the dominant flora in semi-fertile temperate grasslands of northern England. Soil microbial biomass and activity were found to be significantly greater in the more fertile, agriculturally improved soil than in the less

Louise Innes; Philip J. Hobbs; Richard D. Bardgett

2004-01-01

248

Comparative electrophysiological analysis of plant odor perception in females of three Papilio species  

Microsoft Academic Search

Summary Antennae of femalePapilio butterflies perceive many volatile plant constituents with widely differing, constituent-specific sensitivities. We compared the responses of threePapilio species to volatiles from host and non-host plants to assess species-specificity and the degree of evolutionary conservatism in olfactory responses.

Robert Baur; Paul Feeny

1994-01-01

249

Hydrocarbon and rubber-producing crops: evaluation of 100 US plant species  

Microsoft Academic Search

Agricultural production of rubber and other hydrocarbons in the United States may be compatible with increased food and fiber production if entire plants are harvested and processed for fiber, protein, and carbohydrate as well. Procedures and criteria have been established for the preliminary evaluation of plant species as potential multi-use hydrocarbon-producing crops. Previously, 106 species representing 44 families and 81

R. T. Buchanan; I. M. Cull; F. H. Otey; C. R. Russell

1978-01-01

250

Impact of invasive plants on the species richness, diversity and composition of invaded communities  

Microsoft Academic Search

Summary 1. Much attention has been paid to negative effects of alien species on resident communities but studies that quantify community-level effects of a number of invasive plants are scarce. We address this issue by assessing the impact of 13 species invasive in the Czech Republic on a wide range of plant communities. 2. Vegetation in invaded and uninvaded plots

Martin Hejda; Petr Pyšek; Vojt?ch Jarošík

2009-01-01

251

Nutritional and cultural aspects of plant species selection for a controlled ecological life support system  

NASA Technical Reports Server (NTRS)

The feasibility of using higher plants in a controlled ecological life support system is discussed. Aspects of this system considered important in the use of higher plants include: limited energy, space, and mass, and problems relating to cultivation and management of plants, food processing, the psychological impact of vegetarian diets, and plant propagation. A total of 115 higher plant species are compared based on 21 selection criteria.

Hoff, J. E.; Howe, J. M.; Mitchell, C. A.

1982-01-01

252

Plant Species Loss Affects Life-History Traits of Aphids and Their Parasitoids  

PubMed Central

The consequences of plant species loss are rarely assessed in a multi-trophic context and especially effects on life-history traits of organisms at higher trophic levels have remained largely unstudied. We used a grassland biodiversity experiment and measured the effects of two components of plant diversity, plant species richness and the presence of nitrogen-fixing legumes, on several life-history traits of naturally colonizing aphids and their primary and secondary parasitoids in the field. We found that, irrespective of aphid species identity, the proportion of winged aphid morphs decreased with increasing plant species richness, which was correlated with decreasing host plant biomass. Similarly, emergence proportions of parasitoids decreased with increasing plant species richness. Both, emergence proportions and proportions of female parasitoids were lower in plots with legumes, where host plants had increased nitrogen concentrations. This effect of legume presence could indicate that aphids were better defended against parasitoids in high-nitrogen environments. Body mass of emerged individuals of the two most abundant primary parasitoid species was, however, higher in plots with legumes, suggesting that once parasitoids could overcome aphid defenses, they could profit from larger or more nutritious hosts. Our study demonstrates that cascading effects of plant species loss on higher trophic levels such as aphids, parasitoids and secondary parasitoids begin with changed life-history traits of these insects. Thus, life-history traits of organisms at higher trophic levels may be useful indicators of bottom-up effects of plant diversity on the biodiversity of consumers. PMID:20700511

Petermann, Jana S.; Roscher, Christiane; Weigelt, Alexandra; Weisser, Wolfgang W.; Schmid, Bernhard

2010-01-01

253

Investigating Effects of Invasive Species on Plant Community Structure  

ERIC Educational Resources Information Center

In this article, the author presents a field study project that explores factors influencing forest community structure and lifts the veil off of "plant blindness." This ecological study consists of three laboratories: (1) preliminary field trip to the study site; (2) plant survey; and (3) analyzing plant community structure with descriptive…

Franklin, Wilfred

2008-01-01

254

FORUM REVIEW ARTICLE Reactive Oxygen Species in Plant Pathogenesis  

E-print Network

as programmed cell death responses are central to plant defenses against invading pathogens. Contact of ROS, in- cluding hydrogen peroxide (H2O2), which diffuses into cells and activates plant defenses (6). The most characteristic plant defense response is a programmed cell death response (termed

Daub, Margaret

255

The Application of Reverse Genetics to Polyploid Plant Species  

Microsoft Academic Search

Polyploidy events (polyploidization) followed by progressive loss of redundant genome components are a major feature of plant evolution, with new evidence suggesting that all flowering plants possess ancestral genome duplications. Furthermore, many of our most important crop plants have undergone additional, relatively recent, genome duplication events. Recent advances in DNA sequencing have made vast amounts of new genomic data available

Timothy L. Fitzgerald; Kemal Kazan; John M. Manners

2012-01-01

256

Effects of invasive plant species on pollinator service and reproduction in native plants at Acadia National Park  

USGS Publications Warehouse

Invasive plant species can have profound negative effects on natural communities by competively excluding native species. Berberis thunbergii (Japanese barberry), Frangula alnus (glossy or alder buckthorn) and Lythrum salicaria (purple loosestrife) are invasive species known to reduce native plant diversity and are thus of great concern to Acadia National Park. Pollinators visit them for nectar and pollen. The effects of invasive plant species on pollinator behavior were investigated by comparing pollinator visitation to co-flowering native and invasive species with visitation to native species growing alone. The effect of invasives on pollination of native plants was studied by comparing fruit set in patches of the native species growing near invasives with patches far from invasive species in Acadia National Park. The coflowering pairs were as follows: in the spring native Vaccinium angustifolium (lowbush blueberry) was paired with B. thunbergii; in early summer native Viburnum nudum (wild raisin) was paired with F. alnus ; in late summer native Spiraea alba (meadowsweet) was paired with L. salicaria. We investigated whether these invasives competed with native plants for pollinators in Acadia and thus negatively affected native plant reproduction. Our objectives were to determine: 1) the influence, if any, of each invasive on pollinator visitation to a co-flowering native species, 2) factors that might affect visitation, 3) invasive pollen transfer to native plants, and 4) whether invasives influence native plant reproduction (fruit set). Our findings indicate that at times the number of flower visitors to natives was lower or the species composition of visitors different when invasives were present, that invasives sometimes attracted more pollinators, that generally the invasives were more rewarding as far as nectar and pollen availability for pollinators, and that generally native plant fruit set and seed set was not significantly lowered in the presence of the invasive. In fact, in one year fruit set of S. alba was significantly greater in the presence of L. salicaria. The number of invasive pollen grains on native stigmas was extremely low; on average less than one grain per stigma. These fruit set and pollen deposition findings indicate that native plant reproduction was not adversely affected in the short term by these invasive species and that therefore competition between the native and invasive species for pollinators did not occur. Native bee populations monitored in 2004-2005 at sites with and without B. thunbergii and/or F. alnus indicated a greater abundance of native bees at sites with these invasives present. Native bees collected from the native and invasive plants were compared with historical records to assess whether invasive plants favor different bee species than those that formerly predominated on Mount Desert Island. This does not appear to be the case. Several species of bumble bees (Bombus spp.) as well as nine solitary bee species were found that were not documented by the Procter surveys of 1917-1940. Collecting of native bees was limited to the study plants, which may, in part, explain why some bee species documented in the Procter Surveys were not found in the present research. A field guide for identification of native bumble bees has been produced to help Park Natural Resource personnel monitor the status of native bee populations in Acadia. Other educational materials were also developed, aimed at educating Park visitors by exposing them to: 1) the role of native plants and their bee pollinators in terrestrial ecosystems; 2) the effects of invasive plants on native plant-pollinator mutualisms; 3) the need for conserving native bees and other pollinators; and 4) conservation strategies for protecting and enhancing native plant-pollinator mutualisms in the Park. Based on the present findings, Acadia Park Resource Management personnel should continue to closely

Stubbs, C.J.; Drummond, F.; Ginsberg, H.

2007-01-01

257

Plant species coexistence at local scale in temperate swamp forest: test of habitat heterogeneity hypothesis.  

PubMed

It has been suggested that a heterogeneous environment enhances species richness and allows for the coexistence of species. However, there is increasing evidence that environmental heterogeneity can have no effect or even a negative effect on plant species richness and plant coexistence at a local scale. We examined whether plant species richness increases with local heterogeneity in the water table depth, microtopography, pH and light availability in a swamp forest community at three local spatial scales (grain: 0.6, 1.2 and 11.4 m). We also used the variance partitioning approach to assess the relative contributions of niche-based and other spatial processes to species occurrence. We found that heterogeneity in microtopography and light availability positively correlated with species richness, in accordance with the habitat heterogeneity hypothesis. However, we recorded different heterogeneity-diversity relationships for particular functional species groups. An increase in the richness of bryophytes and woody plant species was generally related to habitat heterogeneity at all measured spatial scales, whereas a low impact on herbaceous species richness was recorded only at the 11.4 m scale. The distribution of herbaceous plants was primarily explained by other spatial processes, such as dispersal, in contrast to the occurrence of bryophytes, which was better explained by environmental factors. Our results suggest that both niche-based and other spatial processes are important determinants of the plant composition and species turnover at local spatial scales in swamp forests. PMID:22139430

Douda, Jan; Doudová-Kochánková, Jana; Boublík, Karel; Drašnarová, Alena

2012-06-01

258

Heavy metal uptake by selected marsh plant species grown in hydroponic cultures  

SciTech Connect

Eight marsh plant species (Cyperus esculentus, Scirpus validus, Spartina patens, Scirpus robustus, Triglochin maritima, Distichlis spicata, Spartina alterniflora, and Spartina foliosa) were grown under greenhouse conditions in chemically controlled nutrient solutions. Heavy metals (zinc, cadmium, nickel, chromium, and lead) were added to the nutrient solutions at levels of 0, 0.5, and 1.0 mg/l. Plant parts (leaves, rhizomes, tubers, and roots) were harvested separately for each species and analyzed for heavy metal content. The concentration and plant uptake of heavy metals in each plant species will be discussed.

Lee, C.R.; Sturgis, T.C.; Landin, M.C.

1975-01-01

259

Are Non-Native Plants Perceived to Be More Risky? Factors Influencing Horticulturists' Risk Perceptions of Ornamental Plant Species  

PubMed Central

Horticultural trade is recognized as an important vector in promoting the introduction and dispersal of harmful non-native plant species. Understanding horticulturists' perceptions of biotic invasions is therefore important for effective species risk management. We conducted a large-scale survey among horticulturists in Switzerland (N?=?625) to reveal horticulturists' risk and benefit perceptions from ornamental plant species, their attitudes towards the regulation of non-native species, as well as the factors decisive for environmental risk perceptions and horticulturists' willingness to engage in risk mitigation behavior. Our results suggest that perceived familiarity with a plant species had a mitigating effect on risk perceptions, while perceptions of risk increased if a species was perceived to be non-native. However, perceptions of the non-native origin of ornamental plant species were often not congruent with scientific classifications. Horticulturists displayed positive attitudes towards mandatory trade regulations, particularly towards those targeted against known invasive species. Participants also expressed their willingness to engage in risk mitigation behavior. Yet, positive effects of risk perceptions on the willingness to engage in risk mitigation behavior were counteracted by perceptions of benefits from selling non-native ornamental species. Our results indicate that the prevalent practice in risk communication to emphasize the non-native origin of invasive species can be ineffective, especially in the case of species of high importance to local industries and people. This is because familiarity with these plants can reduce risk perceptions and be in conflict with scientific concepts of non-nativeness. In these cases, it might be more effective to focus communication on well-documented environmental impacts of harmful species. PMID:25003195

Humair, Franziska; Kueffer, Christoph; Siegrist, Michael

2014-01-01

260

Are non-native plants perceived to be more risky? Factors influencing horticulturists' risk perceptions of ornamental plant species.  

PubMed

Horticultural trade is recognized as an important vector in promoting the introduction and dispersal of harmful non-native plant species. Understanding horticulturists' perceptions of biotic invasions is therefore important for effective species risk management. We conducted a large-scale survey among horticulturists in Switzerland (N?=?625) to reveal horticulturists' risk and benefit perceptions from ornamental plant species, their attitudes towards the regulation of non-native species, as well as the factors decisive for environmental risk perceptions and horticulturists' willingness to engage in risk mitigation behavior. Our results suggest that perceived familiarity with a plant species had a mitigating effect on risk perceptions, while perceptions of risk increased if a species was perceived to be non-native. However, perceptions of the non-native origin of ornamental plant species were often not congruent with scientific classifications. Horticulturists displayed positive attitudes towards mandatory trade regulations, particularly towards those targeted against known invasive species. Participants also expressed their willingness to engage in risk mitigation behavior. Yet, positive effects of risk perceptions on the willingness to engage in risk mitigation behavior were counteracted by perceptions of benefits from selling non-native ornamental species. Our results indicate that the prevalent practice in risk communication to emphasize the non-native origin of invasive species can be ineffective, especially in the case of species of high importance to local industries and people. This is because familiarity with these plants can reduce risk perceptions and be in conflict with scientific concepts of non-nativeness. In these cases, it might be more effective to focus communication on well-documented environmental impacts of harmful species. PMID:25003195

Humair, Franziska; Kueffer, Christoph; Siegrist, Michael

2014-01-01

261

Exotic plant species in a C 4 -dominated grassland: invasibility, disturbance, and community structure  

Microsoft Academic Search

We used data from a 15-year experiment in a C4-dominated grassland to address the effects of community structure (i.e., plant species richness, dominance) and disturbance\\u000a on invasibility, as measured by abundance and richness of exotic species. Our specific objectives were to assess the temporal\\u000a and spatial patterns of exotic plant species in a native grassland in Kansas (USA) and to

Melinda D. Smith; Alan K. Knapp

1999-01-01

262

Ecophysiology of cuticular transpiration: comparative investigation of cuticular water permeability of plant species from different habitats  

Microsoft Academic Search

Water permeabilities of astomatous, isolated cuticular membranes (CM) of 24 different plants species were measured. Permeances varied from 1.7×10-11 m·s-1 (Vanilla planifolia leaf) up to 2.1×10-9 m·s-1 (Malus cf. domestica fruit) among different plant species, thus covering a range of over 2 orders of magnitude. Ranking of species according to permeances resulted in four distinct groups. The first group, of

L. Schreiber; M. Riederer

1996-01-01

263

The habitat and conduit functions of roads in the spread of three invasive plant species  

Microsoft Academic Search

Nonnative plant species commonly occur along roadsides, and populations are often assumed to invade by spread along the road\\u000a axis. To distinguish between the function of roadsides as movement corridors and as habitat, nonnative plant species were\\u000a surveyed along roads in deciduous forest sites in southeastern Ohio, USA. The importance of road proximity was tested by comparing\\u000a nonnative species abundance

Douglas C. Christen; Glenn R. Matlack

2009-01-01

264

The Effect of AMF Suppression on Plant Species Composition in a Nutrient-Poor Dry Grassland  

PubMed Central

Arbuscular mycorrhizal fungi (AMF) are expected to be one of the key drivers determining the diversity of natural plant communities, especially in nutrient-poor and dry habitats. Several previous studies have explored the importance of AMF for the composition of plant communities in various types of habitats. Surprisingly, studies of the role of AMF in nutrient-poor dry grassland communities dominated by less mycotrophic plant species are still relatively rare. We present the results of a 3-year study in which a plant community in a species-rich dry grassland was subjected to the fungicide carbendazim to suppress AMF colonization. We tested the effect of the fungicide on the following parameters: the plant species composition; the number of plant species; the cover of the rare, highly mycorrhiza-dependent species Aster amellus; the cover of the dominant, less mycorrhiza-dependent species Brachypodium pinnatum; and the cover of graminoids and perennial forbs. In addition, we examined the mycorrhizal inoculation potential of the soil. We found that the suppression of AMF with fungicide resulted in substantial changes in plant species composition and significant decrease in species richness, the cover of A. amellus and the cover of perennial forbs. In contrast the species increasing their cover after fungicide application were graminoids—the C3 grasses B. pinnatum and Bromus erectus and the sedge Carex flacca. These species appear to be less mycorrhiza dependent. Moreover, due to their clonal growth and efficient nutrient usage, they are, most likely, better competitors than perennial forbs under fungicide application. Our results thus suggest that AMF are an essential part of the soil communities supporting a high diversity of plant species in species-rich dry grasslands in nutrient-poor habitats. The AMF are especially important for the maintenance of the populations of perennial forbs, many of which are rare and endangered in the area. PMID:24265829

Dostalek, Tomas; Pankova, Hana; Munzbergova, Zuzana; Rydlova, Jana

2013-01-01

265

Urban plant species patterns are highly driven by density and function of built-up areas  

Microsoft Academic Search

This paper aims to assess the relative importance of the type of built-up area in structuring plant species composition and\\u000a richness in urbanised environments. The study was carried out in the city of Brussels where all vascular plant species were\\u000a recorded in 189 grid cells of 1 km2 each. The effect of urban land use type on species composition was investigated

Sandrine Godefroid; Nico Koedam

2007-01-01

266

Patterns of invasive plant species distribution in the Upper Volga basin  

Microsoft Academic Search

The patterns of invasive plant species distribution in the Upper Volga basin territory (including five administrative oblasts—Ivanovo,\\u000a Kostroma, Vladimir, Yaroslavl, and Tver) are considered. The present flora of this district comprises 770 alien species, among\\u000a which 135 are successfully naturalized in natural and seminatural communities and 32 (4.2%) are invasive plants. Only 24 invasive\\u000a species (3.1%) are widespread in all

E. A. Borisova

2011-01-01

267

Gross precipitation and throughfall chemistry in legume species planted in Northeastern México  

Microsoft Academic Search

Plant cover modifies throughfall chemistry, and the solute concentration is dependent on the plant species at any given site.\\u000a The chemistry of gross rainfall and throughfall of four endemic species planted in northeastern Mexico was evaluated from\\u000a March 1996 to March 1997. Chemical solutes measured included Ca, K, Mg, Na, Fe, Mn, Cu, and Zn. Dry deposition and canopy\\u000a leaching

José Návar; Jorge Méndez González; Humberto Gonzalez

2009-01-01

268

CHARACTERIZING FIELD-LEVEL HYPERSPECTRAL MEASUREMENTS FOR IDENTIFYING WETLAND INVASIVE PLANT SPECIES  

Microsoft Academic Search

Resource managers can benefit from improved methods for identifying invasive plant species. The utilization of hyperspectral remote sensing as a tool for species-level mapping has been increasing and techniques need to be explored for identifying species of interest. The overarching objective of this paper was to investigate three distinct processing methodologies (i.e., Derivatives, Continuum Removal, and Shape Filter) to explore

Nathan M. Torbicka; Brian L. Becker; Jiaguo Qi; David P. Lusch

269

Resource-based niches provide a basis for plant species diversity and dominance in arctic tundra  

Microsoft Academic Search

Ecologists have long been intrigued by the ways co-occurring species divide limiting resources. Such resource partitioning, or niche differentiation, may promote species diversity by reducing competition. Although resource partitioning is an important determinant of species diversity and composition in animal communities, its importance in structuring plant communities has been difficult to resolve. This is due mainly to difficulties in studying

Robert B. McKane; Loretta C. Johnson; Gaius R. Shaver; Knute J. Nadelhoffer; Edward B. Rastetter; Brian Fry; Anne E. Giblin; Knut Kielland; Bonnie L. Kwiatkowski; James A. Laundre; Georgia Murray

2002-01-01

270

Appendix 15 Red and Blue-Listed Vertebrate and Vascular Plant Species The  

E-print Network

Appendix 15 Red and Blue-Listed Vertebrate and Vascular Plant Species The report that follows lists red- and blue-listed species occurring in the Cranbrook Forest District and in the Southern Rocky risk' as either vulnerable in BC (Blue-listed), or endangered or threatened (Red-listed). The species

271

Controls on pathogen species richness in plants introduced and native ranges: roles of residence  

E-print Network

LETTER Controls on pathogen species richness in plantsÃ? introduced and native ranges: roles,4 Emily E. Puckett1 and Petr Pysek3,4 Abstract Introduced species escape many pathogens and other enemies, raising three questions. How quickly do introduced hosts accumulate pathogen species? What factors control

Kratochvíl, Lukas

272

Trait-Based Filtering of the Regional Species Pool to Guide Understory Plant Reintroductions  

E-print Network

that regenerate vegetatively may outperform other species when introduced to restored sites (Pywell et al. 2003Trait-Based Filtering of the Regional Species Pool to Guide Understory Plant Reintroductions during ecological restoration is rees- tablishing the local species pool through active reintroduc- tion

273

Race to Displace: A Game to Model the Effects of Invasive Species on Plant Communities  

ERIC Educational Resources Information Center

Invasive species are a substantial threat to biodiversity. Educating students about invasive species introduces fundamental concepts in biology, ecology, and environmental science. In the Race to Displace game, students assume the characteristics of select native or introduced plants and experience first hand the influences of species interactions…

Hopwood, Jennifer L.; Flowers, Susan K.; Seidler, Katie J.; Hopwood, Erica L.

2013-01-01

274

The Main Environmental Driving Forces of the Invasive Plant Species in the Romanian Protected Areas  

Microsoft Academic Search

The invasive flora of Romania currently includes more than 400 species (13.87% of the Romanian flora) and according to the third National Report of Biological Diversity Convention, six of them are tree species. Within the protected areas, some of the most representative invasive plant species (IPS) are: Amorpha fruticosa in Balta Mica a Brailei National Park, Ailanthus altissima in Muntii

Monica Dumitrascu; Ines Grigorescu; Mihaela Nastase; Carmen Dragota; Gheorghe Kucsicsa

2010-01-01

275

Hurricane Activity and the Large-Scale Pattern of Spread of an Invasive Plant Species  

E-print Network

Hurricane Activity and the Large-Scale Pattern of Spread of an Invasive Plant Species Ganesh P of invasive species. However, the effects of large-scale disturbances, such as hurricanes and tropical storms, on the broad geographic patterns of invasive species growth and spread have not been investigated. We used

Cronin, James T.

276

Effect of Carpobrotus spp. on the pollination success of native plant species of the Balearic Islands  

Microsoft Academic Search

Invasive plant species are often considered as potential competitors of native species due to their usually greater capacity for colonization and expansion, but we still have scarce information on whether invasives can also compete for pollination services with natives. In the present study, we hypothesized that the showy flowers of the highly invasive Carpobrotu spp. can compete with native species

Eva Moragues; Anna Traveset

2005-01-01

277

Beyond Arabidopsis: the circadian clock in non-model plant species.  

PubMed

Circadian clocks allow plants to temporally coordinate many aspects of their biology with the diurnal cycle derived from the rotation of Earth on its axis. Although there is a rich history of the study of clocks in many plant species, in recent years much progress in elucidating the architecture and function of the plant clock has emerged from studies of the model plant, Arabidopsis thaliana. There is considerable interest in extending this knowledge of the circadian clock into diverse plant species in order to address its role in topics as varied as agricultural productivity and the responses of individual species and plant communities to global climate change and environmental degradation. The analysis of circadian clocks in the green lineage provides insight into evolutionary processes in plants and throughout the eukaryotes. PMID:23466287

McClung, C Robertson

2013-05-01

278

Exotic earthworms of great lakes forests: A search for indicator plant species in maple forests  

Microsoft Academic Search

The invasion of exotic earthworms in previously earthworm-free northern deciduous forests has been linked to the disappearance of forest floor litter, declines in plant species richness, and the development of monotypic stands of Carex pensylvanica. However, the impact of exotic earthworms on the regeneration of trees and understory plants is largely unknown. We examined the relationships between earthworm density, plant

Kathryn Corio; Amy Wolf; Michael Draney; Gary Fewless

2009-01-01

279

Site and species-specific differences in endophyte occurrence in two herbaceous plants  

Microsoft Academic Search

Summary 1 Endophyte fungi exist within the living tissues of all plants, but compared with grasses and trees, remarkably little is known about their ecology in herbaceous species. These fungi produce an array of metabolites in culture and there is some evidence that they can increase the resistance of plants to herbivorous insects. 2 As herbaceous plant endophytes are thought

ALAN C. GANGE; SOMA DEY; AMANDA F. CURRIE; BRIAN C. SUTTON

2007-01-01

280

Observations on the measurement of total antimony and antimony species in algae, plant and animal tissuesw  

E-print Network

Observations on the measurement of total antimony and antimony species in algae, plant and animal of total antimony and antimony speciation in algae, plant and animal tissues. Digestion with nitric acid.g. some plants and algae, the addition of tetrafluorboric acid is required to dissolve silica as some

Canberra, University of

281

Carbon cycling traits of plant species are linked with mycorrhizal strategy  

Microsoft Academic Search

Ecosystem carbon cycling depends strongly on the productivity of plant species and the decomposition rates of the litter they produce. We tested the hypothesis that classifying plant functional types according to mycorrhizal association explains important interspecific variation in plant carbon cycling traits, particularly in those traits that feature in a hypothesized feedback between vegetation productivity and litter turnover. We compared

J. H. C. Cornelissen; R. Aerts; B. Cerabolini; M. J. A. Werger; M. G. A. van der Heijden

2001-01-01

282

Dynamics of host plant use and species diversity in Polygonia butterflies (Nymphalidae)  

Microsoft Academic Search

The ability of insects to utilize different host plants has been suggested to be a dynamic and transient phase. During or after this phase, species can shift to novel host plants or respecialize on ancestral ones. Expanding the range of host plants might also be a factor leading to higher levels of net speciation rates. In this paper, we have

E. WEINGARTNER; N. WAHLBERG; S. NYLIN

2005-01-01

283

Allelopathic Potential of Various Plant Species on Downy Brome: Implications for Weed Control in Wheat Production  

Microsoft Academic Search

Allelopathy, the ability of plants to inhibit germination of other plants, is an untapped resource for weed control in crops that could revolutionize organic crop production. The main objective of the study was to evaluate allelopathic potential of various plant species on downy brome (Bromus tectorum L.), a major pest of wheat (Triticum aestivum L.). To screen for potential allelopathy,

Stephen Machado

284

Effect of density and species richness of soil mesofauna on nutrient mineralisation and plant growth  

Microsoft Academic Search

The aim of this study was to test the relative importance of changes in density and species richness of soil mesofauna as determinants of nutrient mineralisation and plant growth. The experiment was carried out using microcosms containing a mixture of plant litter and soil in which seedlings of Lolium perenne were planted, and a range of combinations of levels of

Lisa Cole; Karsten M. Dromph; Vincent Boaglio; Richard D. Bardgett

2004-01-01

285

Armillaria species on small woody plants, small woody debris, and root fragments in red pine stands  

E-print Network

of incidence inversely related to stand age-class. Large numbers of small woody plants, woody debris, and rootArmillaria species on small woody plants, small woody debris, and root fragments in red pine stands plants, small woody debris, and root fragments was estimated in red pine (Pinus resinosa Ait.) stands

Blanchette, Robert A.

286

Butterfly larvae reduce host plant survival in vicinity of alternative host species  

Microsoft Academic Search

Mortality of an annual plant. Collinsia torreyi, was increased in the vicinity of Pedicularis semibarbata plants. This was a consequence of feeding by Euphydryas editha, a herbivore which feeds on both plant species. Mortality of C. torreyi was better predicted by distance from P. semibarbata than by density of C. torreyi. Since not all herbivores are monophagous, interactions involving distance

C. D. Thomas

1986-01-01

287

Big plants — Do they affect neighbourhood species richness and composition in herbaceous vegetation?  

NASA Astrophysics Data System (ADS)

According to traditional theory, success in competition between plant species generally involves a 'size-advantage'. We predicted therefore that plants with larger body size should impose greater limits on the number of species — especially relatively small ones — that can reside within their immediate neighbourhoods. Species composition was compared within local neighbourhoods surrounding target plants of different sizes belonging to one of the largest herbaceous species found within old-field vegetation in eastern Ontario Canada — Centaurea jacea. Resident species density was generally greater within immediate 'inner' target neighbourhoods than within adjacent circular 'outer' neighbourhoods, and mean body size of resident neighbour species was unrelated to increases in target plant size. As target plant size increased, the proportion of resident neighbour species that were reproductive increased. Relatively big plants of C. jacea do not limit the number or the proportion of reproductive species that can coexist within their immediate neighbourhoods, nor do they cause local exclusion of relatively small species from these neighbourhoods. These results fail to support the 'size-advantage' hypothesis and are more consistent with the 'reproductive economy advantage' hypothesis: success under intense competition is promoted by capacity to recruit offspring that — despite severe suppression — are able to reach their minimum body size needed for reproduction, and hence produce grand-offspring for the next generation. The latter is facilitated by a relatively small minimum reproductive threshold size, which is generally negatively correlated with a relatively large maximum potential body size.

Aarssen, Lonnie W.; Schamp, Brandon S.; Wight, Stephanie

2014-02-01

288

Classification and identification of metal-accumulating plant species by cluster analysis.  

PubMed

Identification and classification of metal-accumulating plant species is essential for phytoextraction. Cluster analysis is used for classifying individuals based on measured characteristics. In this study, classification of plant species for metal accumulation was conducted using cluster analysis based on a practical survey. Forty plant samples belonging to 21 species were collected from an ancient silver-mining site. Five groups such as hyperaccumulator, potential hyperaccumulator, accumulator, potential accumulator, and normal accumulating plant were graded. For Cd accumulation, the ancient silver-mining ecotype of Sedum alfredii was treated as a Cd hyperaccumulator, and the others were normal Cd-accumulating plants. For Zn accumulation, S. alfredii was considered as a potential Zn hyperaccumulator, Conyza canadensis and Artemisia lavandulaefolia were Zn accumulators, and the others were normal Zn-accumulating plants. For Pb accumulation, S. alfredii and Elatostema lineolatum were potential Pb hyperaccumulators, Rubus hunanensis, Ajuga decumbens, and Erigeron annuus were Pb accumulators, C. canadensis and A. lavandulaefolia were potential Pb accumulators, and the others were normal Pb-accumulating plants. Plant species with the potential for phytoextraction were identified such as S. alfredii for Cd and Zn, C. canadensis and A. lavandulaefolia for Zn and Pb, and E. lineolatum, R. hunanensis, A. decumbens, and E. annuus for Pb. Cluster analysis is effective in the classification of plant species for metal accumulation and identification of potential species for phytoextraction. PMID:24888623

Yang, Wenhao; Li, He; Zhang, Taoxiang; Sen, Lin; Ni, Wuzhong

2014-09-01

289

Past and present effectiveness of protected areas for conservation of naturally and anthropogenically rare plant species.  

PubMed

The Global Strategy of Plant Conservation states that at least 60% of threatened plant species should be within protected areas. This goal has been met in some regions with long traditions of plant protection. We used gap analysis to explore how particular groups of species of conservation interest, representing different types of natural or anthropogenic rarity, have been covered by protected areas on a national scale in Estonia during the last 100 years. Species-accumulation curves indicated that plant species that are naturally rare (restricted global or local distribution, always small populations, or very rare habitat requirements) needed almost twice as many protected areas to reach the 60% target as plant species that are rare owing to lack of suitable management (species depending on grassland management, moderate forest disturbances, extensive traditional agriculture, or species potentially threatened by collecting). Temporal analysis of the establishment of protected areas suggested that grouping plant species according to the predominant cause of rarity accurately reflected the history of conservation decision making. Species found in very rare habitats have previously received special conservation attention; species dependent on traditional extensive agriculture have been largely ignored until recently. Legislative initiative and new nature-protection schemes (e.g., Natura 2000, network of protected areas in the European Union) have had a positive influence on all species groups. Consequently, the species groups needing similar action for their conservation are sensitive indicators of the effectiveness of protected-area networks. Different species groups, however, may not be uniformly conserved within protected areas, and all species groups should fulfill the target of 60% coverage within protected areas. PMID:19128324

Vellak, Ain; Tuvi, Eva-Liis; Reier, Ülle; Kalamees, Rein; Roosaluste, Elle; Zobel, Martin; Pärtel, Meelis

2009-06-01

290

Plant translational genomics: from model species to crops  

Microsoft Academic Search

Plant genomic research now faces the ultimate challenge to develop applications in crop plants which implies the translation\\u000a of gene functions from a model to a crop which is the field of ‘Plant translational genomics’. In this paper we discuss the\\u000a perspectives of the candidate gene approach (CGA) as a tool for translational genomics in the ‘whole genome’ era. Factors

Elma M. J. Salentijn; Andy Pereira; Gerco C. Angenent; C. Gerard van der Linden; Frans Krens; Marinus J. M. Smulders; Ben Vosman

2007-01-01

291

The effects of plant diversity and insect herbivory on performance of individual plant species in experimental grassland  

Microsoft Academic Search

1 There is increasing evidence that components of biodiversity affect processes at the ecosystem level; yet, the effects of biodiversity on the performance of individual organisms or particular trophic interactions are largely unexplored. 2 We transplanted 10 individuals of Rumex acetosa into 82 experimental grassland plots differing in plant species and functional group richness. Half of the plants received an

CHRISTOPH SCHERBER; ALEXANDRU MILCU; STEPHAN PARTSCH; STEFAN SCHEU; WOLFGANG W. WEISSER

2006-01-01

292

Spectrometry for plant species recognition in Mediterranean forest canopies - Spectral separability and image unmixing studied on field and aerial data.  

E-print Network

??Mediterranean-type forests are formed by heterogeneous, dense communities. This condition represents a challenge for plant species discrimination using optical remote sensing. The detection of species… (more)

Buzzo, G.

2012-01-01

293

A comparative study of AMF diversity in annual and perennial plant species from semiarid gypsum soils.  

NASA Astrophysics Data System (ADS)

The arbuscular mycorrhizal fungi (AMF) communities composition regulate plant interactions and determine the structure of plant communities. In this study we analysed the diversity of AMF in the roots of two perennial gypsophyte plant species, Herniaria fruticosa and Senecio auricula, and an annual herbaceous species, Bromus rubens, growing in a gypsum soil from a semiarid area. The objective was to determine whether perennial and annual host plants support different AMF communities in their roots and whether there are AMF species that might be indicators of specific functional plant roles in these ecosystems. The roots were analysed by nested PCR, cloning, sequencing of the ribosomal DNA small subunit region and phylogenetic analysis. Twenty AMF sequence types, belonging to the Glomus group A, Glomus group B, Diversisporaceae, Acaulosporaceae, Archaeosporaceae and Paraglomeraceae, were identified. Both gypsophyte perennial species had differing compositions of the AMF community and higher diversity when compared with the annual species, showing preferential selection by specific AMF sequences types. B. rubens did not show host specificity, sharing the full composition of its AMF community with both perennial plant species. Seasonal variations in the competitiveness of AM fungi could explain the observed differences in AMF community composition, but this is still a working hypothesis that requires the analysis of further data obtained from a higher number of both annual and perennial plant species in order to be fully tested.

Alguacil, M. M.; Torrecillas, E.; Roldán, A.; Díaz, G.; Torres, P.

2012-04-01

294

Individual-based ant-plant networks: diurnal-nocturnal structure and species-area relationship.  

PubMed

Despite the importance and increasing knowledge of ecological networks, sampling effort and intrapopulation variation has been widely overlooked. Using continuous daily sampling of ants visiting three plant species in the Brazilian Neotropical savanna, we evaluated for the first time the topological structure over 24 h and species-area relationships (based on the number of extrafloral nectaries available) in individual-based ant-plant networks. We observed that diurnal and nocturnal ant-plant networks exhibited the same pattern of interactions: a nested and non-modular pattern and an average level of network specialization. Despite the high similarity in the ants' composition between the two collection periods, ant species found in the central core of highly interacting species totally changed between diurnal and nocturnal sampling for all plant species. In other words, this "night-turnover" suggests that the ecological dynamics of these ant-plant interactions can be temporally partitioned (day and night) at a small spatial scale. Thus, it is possible that in some cases processes shaping mutualistic networks formed by protective ants and plants may be underestimated by diurnal sampling alone. Moreover, we did not observe any effect of the number of extrafloral nectaries on ant richness and their foraging on such plants in any of the studied ant-plant networks. We hypothesize that competitively superior ants could monopolize individual plants and allow the coexistence of only a few other ant species, however, other alternative hypotheses are also discussed. Thus, sampling period and species-area relationship produces basic information that increases our confidence in how individual-based ant-plant networks are structured, and the need to consider nocturnal records in ant-plant network sampling design so as to decrease inappropriate inferences. PMID:24918750

Dáttilo, Wesley; Fagundes, Roberth; Gurka, Carlos A Q; Silva, Mara S A; Vieira, Marisa C L; Izzo, Thiago J; Díaz-Castelazo, Cecília; Del-Claro, Kleber; Rico-Gray, Victor

2014-01-01

295

Species richness and patterns of invasion in plants, birds, and fishes in the United States  

USGS Publications Warehouse

We quantified broad-scale patterns of species richness and species density (mean # species/km2) for native and non-indigenous plants, birds, and fishes in the continental USA and Hawaii. We hypothesized that the species density of native and non-indigenous taxa would generally decrease in northern latitudes and higher elevations following declines in potential evapotranspiration, mean temperature, and precipitation. County data on plants (n = 3004 counties) and birds (n=3074 counties), and drainage (6 HUC) data on fishes (n = 328 drainages) showed that the densities of native and non-indigenous species were strongly positively correlated for plant species (r = 0.86, P < 0.0001), bird species (r = 0.93, P<0.0001), and fish species (r = 0.41, P<0.0001). Multiple regression models showed that the densities of native plant and bird species could be strongly predicted (adj. R2 = 0.66 in both models) at county levels, but fish species densities were less predictable at drainage levels (adj. R2 = 0.31, P<0.0001). Similarly, non-indigenous plant and bird species densities were strongly predictable (adj. R2 = 0.84 and 0.91 respectively), but non-indigenous fish species density was less predictable (adj. R2 = 0.38). County level hotspots of native and non-indigenous plants, birds, and fishes were located in low elevation areas close to the coast with high precipitation and productivity (vegetation carbon). We show that (1) native species richness can be moderately well predicted with abiotic factors; (2) human populations have tended to settle in areas rich in native species; and (3) the richness and density of non-indigenous plant, bird, and fish species can be accurately predicted from biotic and abiotic factors largely because they are positively correlated to native species densities. We conclude that while humans facilitate the initial establishment, invasions of non-indigenous species, the spread and subsequent distributions of non-indigenous species may be controlled largely by environmental factors.

Stohlgren, T.J.; Barnett, D.; Flather, C.; Fuller, P.; Peterjohn, B.; Kartesz, J.; Master, L.L.

2006-01-01

296

Disturbance, spatial turnover, and species coexistence in grassland plant communities  

E-print Network

and differences in community composition among habitat patches at three spatial scales, at two levels of ecological resolution, and at three levels of taxonomic resolution. There were extensive changes to plant community structure associated with grassland...

Questad, Erin

2008-08-18

297

Habitat types on the Hanford Site: Wildlife and plant species of concern  

SciTech Connect

The objective of this report is to provide a comprehensive source of the best available information on Hanford Site sensitive and critical habitats and plants and animals of importance or special status. In this report, sensitive habitats include areas known to be used by threatened, endangered, or sensitive plant or animal species, wetlands, preserves and refuges, and other sensitive habitats outlined in the Hanford Site Baseline Risk Assessment Methodology. Potentially important species for risk assessment and species of special concern with regard to their status as threatened, endangered, or sensitive are described, and potential habitats for these species identified.

Downs, J.L.; Rickard, W.H.; Brandt, C.A. [and others

1993-12-01

298

Contrasting Soil Ciliate Species Richness and Abundance between Two Tropical Plant Species: A Test of the Plant Effect  

Microsoft Academic Search

We still have a rudimentary understanding about the mechanism by which plant roots may stimulate soil microbial interactions. A biochemical model involving plant-derived biochemical fractions, such as exudates, has been used to explain this “rhizosphere effect” on bacteria. However, the variable response of other soil microbial groups, such as protozoa, to the rhizosphere suggests that other factors could be involved

D. Acosta-Mercado; D. H. Lynn

2006-01-01

299

Species richness and selenium accumulation of plants in soils with elevated concentration of selenium and salinity.  

PubMed

Field studies were conducted in soils with elevated concentrations of Se and salinity at Kesterson, California. Biomass distribution, species richness, and selenium accumulation of plants were examined for two sites where 15 cm of surface soil was removed and replaced with fill dirt in the fall of 1989, and two sites were native soil cover. The Se concentrations in the top 15 cm of fill dirt ranged from undetectable to 36 ng g-1. For the native soil sites, Se levels ranged from 75 to 550 ng g-1. Soil Se concentrations below 15 cm ranged from 300 to 700 ng g-1 and were comparable between the fill dirt and the native soil sites. At least 20 different plant species were brought into the two fill dirt sites with the top soil. Avena fatua L., Bassia hyssopifolia Kuntze Rev. Gen. Pl., Centaurea solstitialis L., Erysimum officianale L., Franseria acanthicarpa Cav. Icon., and Melilotus indica (L.) All. contributed over 60% of the total biomass. Only 5 species were found in the native soil sites, and salt grass (Distichlis spicata L.) was the predominant species and accounted for over 80% of the total biomass. Between 1989 and 1990, two years after the surface soil replacement, the two fill dirt sites had a 70% reduction in species richness. Plant tissue selenium concentrations were found to be quite variable between plant species and between sites of sampling. At the fill dirt sites, the plant species with deep root systems accumulated greater amounts of selenium than the shallow-rooted species. The soil selenium concentration of the field soil had no negative effect on pollen fertility, seed set, and seed germination for the plant species examined. However, seedling growth was impaired by the soil selenium concentrations. This suggests that a selection pressure of soil Se concentration may have been imposed on plant species such as M. indica in an early stage of its life cycle. PMID:1778114

Huang, Z Z; Wu, L

1991-12-01

300

Species richness and selenium accumulation of plants in soils with elevated concentration of selenium and salinity  

SciTech Connect

Field studies were conducted in soils with elevated concentrations of Se and salinity at Kesterson, California. Biomass distribution, species richness, and selenium accumulation of plants were examined for two sites where 15 cm of surface soil was removed and replaced with fill dirt in the fall of 1989, and two sites were native soil cover. The Se concentrations in the top 15 cm of fill dirt ranged from undetectable to 36 ng g-1. For the native soil sites, Se levels ranged from 75 to 550 ng g-1. Soil Se concentrations below 15 cm ranged from 300 to 700 ng g-1 and were comparable between the fill dirt and the native soil sites. At least 20 different plant species were brought into the two fill dirt sites with the top soil. Avena fatua L., Bassia hyssopifolia Kuntze Rev. Gen. Pl., Centaurea solstitialis L., Erysimum officianale L., Franseria acanthicarpa Cav. Icon., and Melilotus indica (L.) All. contributed over 60% of the total biomass. Only 5 species were found in the native soil sites, and salt grass (Distichlis spicata L.) was the predominant species and accounted for over 80% of the total biomass. Between 1989 and 1990, two years after the surface soil replacement, the two fill dirt sites had a 70% reduction in species richness. Plant tissue selenium concentrations were found to be quite variable between plant species and between sites of sampling. At the fill dirt sites, the plant species with deep root systems accumulated greater amounts of selenium than the shallow-rooted species. The soil selenium concentration of the field soil had no negative effect on pollen fertility, seed set, and seed germination for the plant species examined. However, seedling growth was impaired by the soil selenium concentrations. This suggests that a selection pressure of soil Se concentration may have been imposed on plant species such as M. indica in an early stage of its life cycle.

Huang, Z.Z.; Wu, L. (Department of Environmental Horticulture, University of California, Davis (United States))

1991-12-01

301

Plant species diversity and composition of wetlands within an upland forest.  

PubMed

Though often overlooked, small wetlands in an upland matrix can support diverse plant communities that increase both local and regional species richness. Here we characterize the full range of wetland vegetation within an upland forest landscape and compare the diversity and composition of different wetland plant communities. In an old-growth forest reserve in southern Quebec, Canada, we sampled wet habitats including lakeshores, permanent and seasonal ponds, swamps, glades, and streamsides. We used clustering, indicator species analysis, and nonmetric multidimensional scaling ordination to identify and compare vegetation types. The wetlands contained 280 species of vascular plants, 45% of the reserve's flora, in only 1.1% of its area. Local diversity averaged 24 ± 0.7 species per 7 m(2), much higher than in the surrounding upland forests. Plant communities sorted into five types, whose strongest indicator species were Osmunda regalis, Glyceria striata, O. cinnamomea, Deparia acrostichoides, and Matteuccia struthiopteris, respectively. Both local species richness and compositional variation among sites differed among the vegetation types. By combining species representative of the region's major wetlands with species from the upland forest matrix, the plant assemblages of these wetlands make disproportionately important contributions to landscape-level diversity. PMID:21632326

Flinn, Kathryn M; Lechowicz, Martin J; Waterway, Marcia J

2008-10-01

302

Vanadium uptake and translocation in dominant plant species on an urban coastal brownfield site.  

PubMed

This study, conducted at a brownfield site in New Jersey, USA, investigated factors controlling V uptake and translocation in naturally assembled plant species. Six dominant species were collected from 22 stations in the study area. We found that V concentration in the plants decreased in a sequence of root>leaf>stem. No significant differences were found among the six dominant plant species in terms of root V uptake efficiency (V BCF) and V root to shoot translocation (V TF). Although soil pH and TOC did not show significant impact on V accumulation in the roots, soil labile V content showed significant positive linear correlation (p<0.05) with plant root V. Non-linear regression analysis indicates that V translocation efficiency decreases with increasing concentration in the soil, implying that excessive V in the soil might inhibit its absorption by the plant roots. Leaf V concentration was constant in all the plant species regardless of the variation in soil V concentration. The study shows that the six dominant plant species on site had limited amount of V translocated to the aerial part of the plant. PMID:24518306

Qian, Yu; Gallagher, Frank J; Feng, Huan; Wu, Meiyin; Zhu, Qingzhi

2014-04-01

303

A population genomic analysis of species boundaries: neutral processes, adaptive divergence and introgression between two hybridizing plant species.  

PubMed

Little is known about the nature of species boundaries between closely related plant species and about the extent of introgression as a consequence of hybridization upon secondary contact. To address these topics we analyzed genome-wide differentiation between two closely related Silene species, Silene latifolia and S. dioica, and assessed the strength of introgression in sympatry. More than 300 AFLP markers were genotyped in three allopatric and three sympatric populations of each species. Outlier analyses were performed separately for sympatric and allopatric populations. Both positive and negative outlier loci were found, indicating that divergent and balancing selection, respectively, have shaped patterns of divergence between the two species. Sympatric populations of the two species were found to be less differentiated genetically than allopatric populations, indicating that hybridization has led to gene introgression. We conclude that differentiation between S. latifolia and S. dioica has been shaped by a combination of introgression and selection. These results challenge the view that species differentiation is a genome-wide phenomenon, and instead support the idea that genomes can be porous and that species differentiation has a genic basis. PMID:18321255

Minder, A M; Widmer, A

2008-03-01

304

Leaching requirement and salinity threshold for the yield and agronomic characteristics of halophytes under salt stress  

Microsoft Academic Search

An experiment was carried out at Nahshala Farm, north west of Al-Ain City, U.A.E. during the 1998–2000 growing seasons, using six halophytes (Batis maritima, Distichlis spicata, Juncus roemerianus, Paspalum vaginatum, Salicornia bigelovii and Spartina alterniflora) and two levels of leaching fraction (0·25 and 0·50) under three irrigation salinity levels (10, 20, and 40 gL?1) in a randomized complete block design

El-Sayed H. El-Haddad; Maher M. Noaman

2001-01-01

305

Soil lichens have species-specific effects on the seedling emergence of three gypsophile plant species  

Microsoft Academic Search

Despite advancements in our knowledge on the importance of biological soil crusts (BSC) in arid and semiarid environments, little is known on the effects of specific crust organisms on vascular plant seed emergence. We conducted a growth chamber experiment to evaluate the effects of two BSC-forming lichens (Squamarina lentigera and Diploschistes diacapsis) on the emergence of three specialist vascular plants

A. Escudero; I. Martínez; A. de la Cruz; M. A. G. Otálora; F. T. Maestre

2007-01-01

306

Areas of Increasing Agricultural Abandonment Overlap the Distribution of Previously Common, Currently Threatened Plant Species  

PubMed Central

Human-driven land-use changes increasingly threaten biodiversity. In agricultural ecosystems, abandonment of former farmlands constitutes a major land-use shift. We examined the relationships between areas in which agriculture has been abandoned and the distribution records of threatened plant species across Japan. We selected 23 plant species that are currently identified as threatened but were previously common in the country as indicators of threatened plant species. The areas of abandoned farmlands within the distribution ranges of the indicator species were significantly larger than the proportion of abandoned farmland area across the whole country. Also, abandoned farmland areas were positively correlated with the occurrence of indicator species. Therefore, sections of agricultural landscape that are increasingly becoming abandoned and the distribution ranges of indicator species overlapped. These results suggest that abandoned farmland areas contain degraded or preferred habitats of threatened plant species. We propose that areas experiencing increased abandonment of farmland can be divided into at least two categories: those that threaten the existence of threatened species and those that provide habitats for these threatened species. PMID:24260328

Osawa, Takeshi; Kohyama, Kazunori; Mitsuhashi, Hiromune

2013-01-01

307

Visiting insect diversity and visitation rates for seven globally-imperiled plant species in  

E-print Network

Visiting insect diversity and visitation rates for seven globally-imperiled plant species in Colorado's middle Arkansas Valley by Susan C. Spackman Panjabi Colorado Natural Heritage Program College............................................................................................ 20 Measuring insect visitation rates

308

Interlaboratory Root Elongation Testing of Toxic Substances on Selected Plant Species.  

National Technical Information Service (NTIS)

Four contract laboratories and three EPA laboratories participated in the inter-laboratory testing of 10 toxic substances on a representative plant species from five families. Seeds were germinated on filter paper saturated in a solution of the toxic subs...

H. C. Ratsch

1983-01-01

309

AN ECOLOGICAL ASSESSMENT OF OPPORTUNISTIC PLANT SPECIES IN GREAT LAKES COASTAL WETLANDS USING AIRBORNE HYPERSPECTRAL DATE  

EPA Science Inventory

Airbome hyperspectral data were used to detect dense patches of Phragmites australis, a native opportunist plant species, at the Pointe Mouillee coastal wetland complex (Wayne and Monroe Counties, Michigan). This study provides initial results from one of thirteen coastal wetland...

310

ACCURACY ASSESSMENTS OF AIRBORNE HYSPERSPECTRAL DATA FOR MAPPING OPPORTUNISTIC PLANT SPECIES IN FRESHWATER COASTAL WETLANDS  

EPA Science Inventory

Airbome hyperspectral data were used to detect dense patches of Phragmites australis, a native opportunist plant species, at the Pointe Mouillee coastal wetland complex (Wayne and Monroe Counties, Michigan). This study provides initial results from one of thirteen coastal wetland...

311

Tropical leguminous species for acid soils: studies on plant form and growth  

E-print Network

Many forest plantations in the humid neo-tropics are established on degraded soils in abandoned pasture land, and with some exceptions, the species planted have not grown successfully. Few studies of adaptability and growth under these conditions...

Tilki, Fahrettin

2012-06-07

312

Mapping plant species ranges in the Hawaiian Islands: developing a methodology and associated GIS layers  

USGS Publications Warehouse

This report documents a methodology for projecting the geographic ranges of plant species in the Hawaiian Islands. The methodology consists primarily of the creation of several geographic information system (GIS) data layers depicting attributes related to the geographic ranges of plant species. The most important spatial-data layer generated here is an objectively defined classification of climate as it pertains to the distribution of plant species. By examining previous zonal-vegetation classifications in light of spatially detailed climate data, broad zones of climate relevant to contemporary concepts of vegetation in the Hawaiian Islands can be explicitly defined. Other spatial-data layers presented here include the following: substrate age, as large areas of the island of Hawai'i, in particular, are covered by very young lava flows inimical to the growth of many plant species; biogeographic regions of the larger islands that are composites of multiple volcanoes, as many of their species are restricted to a given topographically isolated mountain or a specified group of them; and human impact, which can reduce the range of many species relative to where they formerly were found. Other factors influencing the geographic ranges of species that are discussed here but not developed further, owing to limitations in rendering them spatially, include topography, soils, and disturbance. A method is described for analyzing these layers in a GIS, in conjunction with a database of species distributions, to project the ranges of plant species, which include both the potential range prior to human disturbance and the projected present range. Examples of range maps for several species are given as case studies that demonstrate different spatial characteristics of range. Several potential applications of species-range maps are discussed, including facilitating field surveys, informing restoration efforts, studying range size and rarity, studying biodiversity, managing invasive species, and planning of conservation efforts.

Price, Jonathan P.; Jacobi, James D.; Gon, Samuel M., III; Matsuwaki, Dwight; Mehrhoff, Loyal; Wagner, Warren; Lucas, Matthew; Rowe, Barbara

2012-01-01

313

Surface flavonoid aglycones in newly studied plant species.  

PubMed

Several newly studied species of the Scrophulariaceae, Lamiaceae, and Ranunculaceae spread in Bulgaria have been analyzed for their surface flavonoid profiles. Except Pulsatilla montana (Hope) Rchb. (Ranunculaceae) all taxa now studied accumulated mainly apigenin, luteolin, and it's derivatives. This is the first report for the presence on external flavonoid aglycones in genus Pulsatilla. Quercetin-3'-methyl ether is a new citation for P. montana. The presence on surface flavonoid aglycones in species Veronica bellidioides L., V. persica Poir., Odontites verna (Bell.) Dum., Laminiastrum galeobdolon Heist ex Fabr., Glechoma herbaceae L., Ajuga genevensis L., and A. reptans L. are reported for the first time too. PMID:16286319

Nikolova, M; Asenov, A

2006-01-01

314

Deep transcriptome sequencing of wild halophyte rice, Porteresia coarctata, provides novel insights into the salinity and submergence tolerance factors.  

PubMed

Porteresia coarctata is a wild relative of rice with capability of high salinity and submergence tolerance. The transcriptome analyses of Porteresia can lead to the identification of candidate genes involved in salinity and submergence tolerance. We sequenced the transcriptome of Porteresia under different conditions using Illumina platform and generated about 375 million high-quality reads. After optimized assembly, a total of 152 367 unique transcript sequences with average length of 794 bp were obtained. Many of these sequences might represent fragmented transcripts. Functional annotation revealed the presence of genes involved in diverse cellular processes and 2749 transcription factor (TF)-encoding genes in Porteresia. The differential gene expression analyses identified a total of 15 158 genes involved in salinity and/or submergence response(s). The stress-responsive members of different TF families, including MYB, bHLH, AP2-EREBP, WRKY, bZIP and NAC, were identified. We also revealed key metabolic pathways, including amino acid biosynthesis, hormone biosynthesis, secondary metabolite biosynthesis, carbohydrate metabolism and cell wall structures, involved in stress tolerance in Porteresia. The transcriptome analyses of Porteresia are expected to highlight genes/pathways involved in salinity and submergence tolerance of this halophyte species. The data can serve as a resource for unravelling the underlying mechanism and devising strategies to engineer salinity and submergence tolerance in rice. PMID:24104396

Garg, Rohini; Verma, Mohit; Agrawal, Shashank; Shankar, Rama; Majee, Manoj; Jain, Mukesh

2014-02-01

315

Plant species identity and diversity effects on different trophic levels of nematodes in the soil food web  

Microsoft Academic Search

Previous studies on biodiversity and soil food web composition have mentioned plant species identity, as well as plant species diversity as the main factors affecting the abundance and diversity of soil organisms. However, most studies have been carried out under limitations of time, space, or appropriate controls. In order to further examine the relation between plant species diversity and the

Gerlinde B. De Deyn; Ciska E. Raaijmakers; Jasper van Ruijven; Frank Berendse; Wim H. van der Putten

2004-01-01

316

Mapping invasive plant species in aquatic and terrestrial ecosystems helps to understand the causes of their progres-  

E-print Network

Abstract Mapping invasive plant species in aquatic and terrestrial ecosystems helps to understand. Introduction The invasion of aquatic and terrestrial ecosystems by non- indigenous plant and animal species of Optimal Dates for the Discrimination of Invasive Wetland Plant Species Using Derivative Spectral Analysis

Tsai, Fuan "Alfonso"

317

Variation in habitat suitability does not always relate to variation in species' plant functional traits  

PubMed Central

Habitat suitability models, which relate species occurrences to environmental variables, are assumed to predict suitable conditions for a given species. If these models are reliable, they should relate to change in plant growth and function. In this paper, we ask the question whether habitat suitability models are able to predict variation in plant functional traits, often assumed to be a good surrogate for a species' overall health and vigour. Using a thorough sampling design, we show a tight link between variation in plant functional traits and habitat suitability for some species, but not for others. Our contrasting results pave the way towards a better understanding of how species cope with varying habitat conditions and demonstrate that habitat suitability models can provide meaningful descriptions of the functional niche in some cases, but not in others. PMID:19793738

Thuiller, Wilfried; Albert, Cecile H.; Dubuis, Anne; Randin, Christophe; Guisan, Antoine

2010-01-01

318

Growth response of selected vegetable species to plant residue of guar (Cyamopsis tetragonoloba (L.) Taub.)  

E-print Network

in 1971 that western ragweed (Ambrosia psilostachya D. C. ) stimulated the growth of several species of plants in the same field including Amaranthus retrogexus L. Rudebeckia hirta L. and Digi taria sanguinalis (L. ) Scop. Several other weeds that have... in 1971 that western ragweed (Ambrosia psilostachya D. C. ) stimulated the growth of several species of plants in the same field including Amaranthus retrogexus L. Rudebeckia hirta L. and Digi taria sanguinalis (L. ) Scop. Several other weeds that have...

Reid, Debbie John

2012-06-07

319

Extensively managed strips in intensively cultivated grasslands as possible contributors to increased plant species richness  

Microsoft Academic Search

This four-year study investigated whether partitioning intensively managed grass crop fields by non-fertilized, extensively managed permanent strips created new habitats for semi-natural grassland plants and contributed to increased plant species richness. The strips were set aside in the grass crop or ploughed at the start of the experiment, and either uncut or cut each autumn. Uncut strips became species-poor and

Hege Hovd

2008-01-01

320

Mycorrhizal status of plant species in the Chaco Serrano Woodland from central Argentina  

Microsoft Academic Search

We examined the mycorrhizal type of 128 plant species in two patches of native vegetation of the Chaco Serrano Woodland, central\\u000a Argentina, the largest dry forest area in South America. Of the 128 plant species investigated (belonging to 111 genera in\\u000a 53 families), 114 were colonized by arbuscular mycorrhizal fungi (AM), orchid mycorrhizal associations were present in the\\u000a five terrestrial

Sebastian Fracchia; Adriana Aranda; Analia Gopar; Vanesa Silvani; Laura Fernandez; Alicia Godeas

2009-01-01

321

Plant species as a significant factor in wastewater treatment in constructed wetlands  

E-print Network

to be determined (Kadlec and Knight, 1996). According to Gregory Sauter and Kathleen Leonard (1995), plant life should be chosen fiom indigenous species of Typhaceae (cattails), Cyperacaea (sedge), Gramineae (grass), Scirpus (buhush), and Phragmites (reeds... to be determined (Kadlec and Knight, 1996). According to Gregory Sauter and Kathleen Leonard (1995), plant life should be chosen fiom indigenous species of Typhaceae (cattails), Cyperacaea (sedge), Gramineae (grass), Scirpus (buhush), and Phragmites (reeds...

Varvel, Tracey W

2013-02-22

322

Population Dynamics of Scirtothrips dorsalis (Thysanoptera: Thripidae) and Other Thrips Species on Two Ornamental Host Plant Species in Southern Florida.  

PubMed

Since its 2005 introduction into the United States, chilli thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae), has become a problematic pest of agronomic, vegetable, fruit, and ornamental plants. Knowledge of its population dynamics may help managers better monitor and control S. dorsalis. Population estimates were recorded for S. dorsalis and other thrips species on Knock-Out rose (Rosa 'Radrazz') and green buttonwood (Conocarpus erectus L.) from July 2007 to September 2008 in two field plots (one per plant species) in Homestead, FL. Yellow sticky card traps and samples of terminals, flowers, buds, and leaves were collected. S. dorsalis accounted for 95% of all thrips individuals collected from plants and 84% from traps with the remainder including at least 18 other thrips species. More thrips were caught on or flying near rose plants (47,438) than on or near buttonwoods (5,898), and on-plant densities of S. dorsalis appeared higher for rose than for buttonwood. Compared with rose leaves, rose buds, terminals, and flowers each had higher numbers of S. dorsalis, and buds and terminals had higher densities. On each host plant species, S. dorsalis density fluctuated over time with peaks in the late spring, summer, and fall, but populations were consistently low in the late winter and early spring. On roses, increased plant damage ratings correlated with reduced numbers of flowers and buds, reduced mean flower areas, and increased on-plant number and density of S. dorsalis. There were positive correlations over time between S. dorsalis density and plant damage rating for rose flowers (R = 0.78; P = 0.0003) and for buttonwood terminals (R = 0.90; P = 0.0001). Yellow sticky card traps were effective for monitoring S. dorsalis and may be especially useful and economically justified for the most susceptible hosts, but they also work well for less susceptible hosts. A good S. dorsalis scouting program should hence consider trap catches and symptoms such as leaf distortion, small flower area (size), and thrips population concentrations near buds and terminals. PMID:25182610

Mannion, Catharine M; Derksen, Andrew I; Seal, Dakshina R; Osborne, Lance S; Martin, Cliff G

2014-08-01

323

Patch Size and Isolation Predict Plant Species Density in a Naturally Fragmented Forest  

PubMed Central

Studies of the effects of patch size and isolation on plant species density have yielded contrasting results. However, much of the available evidence comes from relatively recent anthropogenic forest fragments which have not reached equilibrium between extinction and immigration. This is a critical issue because the theory clearly states that only when equilibrium has been reached can the number of species be accurately predicted by habitat size and isolation. Therefore, species density could be better predicted by patch size and isolation in an ecosystem that has been fragmented for a very long time. We tested whether patch area, isolation and other spatial variables explain variation among forest patches in plant species density in an ecosystem where the forest has been naturally fragmented for long periods of time on a geological scale. Our main predictions were that plant species density will be positively correlated with patch size, and negatively correlated with isolation (distance to the nearest patch, connectivity, and distance to the continuous forest). We surveyed the vascular flora (except lianas and epiphytes) of 19 forest patches using five belt transects (50×4 m each) per patch (area sampled per patch?=?0.1 ha). As predicted, plant species density was positively associated (logarithmically) with patch size and negatively associated (linearly) with patch isolation (distance to the nearest patch). Other spatial variables such as patch elevation and perimeter, did not explain among-patch variability in plant species density. The power of patch area and isolation as predictors of plant species density was moderate (together they explain 43% of the variation), however, a larger sample size may improve the explanatory power of these variables. Patch size and isolation may be suitable predictors of long-term plant species density in terrestrial ecosystems that are naturally and anthropogenically fragmented. PMID:25347818

Munguia-Rosas, Miguel A.; Montiel, Salvador

2014-01-01

324

Responses of wild plant species to polycyclic aromatic hydrocarbons in soil.  

PubMed

Responses of plants to polycyclic aromatic hydrocarbons (PAHs) contamination were determined with fifty-five Korean wild plants. Responsiveness of species was evaluated based on germination and shoot weight and shoot length of plants grown in soil spiked with four PAHs (pyrene, fluorene, phenanthrene and fluoranthene). Seeds of test plants were germinated with mixtures of PAHs of 0, 10, 30, 100, 300 mg kg(-1) spiked in soil. Seed germination of test plants changed when subjected to PAHs. As compared to control germination percentages ranged from 0 (completely inhibited) to 242.9% (highly promoted) of control at 300 mg kg(-1) of PAHs. In germination responses, Fabaceae plants were much less affected (105% of control) compared to species belonging to Caryophyllaceae (18.7% of control), which showed highly susceptible responses. Results demonstrated that seed germination was affected by species-specific responses to PAHs. In seedling growth experiments on Bromus tectorum and Veronica persica, species classified as highly susceptible in germination experiments, a low No Observed Effect Concentration (NOEC) of 10 mg kg(-1) was observed. On the other hand, NOEC was 100 mg kg(-1) in Bromus japonicus and Cerastium holosteoides var. hallaisanense, which were also classified as highly susceptible by the germination experiment. However, most species classified as susceptible showed high NOEC of greater than 10 mg kg(-1). EC(50) values of test species ranged from 2.87 x 10(2) (Humulus japonicus) to 8.05 x 10(81) mg kg(-1) (Bidens bipinnata) based on shoot length. The wide range of EC(50) for shoot weight suggests that shoot weight is more appropriate as an endpoint for PAHs toxicity than shoot length for determining the susceptibility of plant species to PAHs. It was confirmed that dose-response of plants to PAHs spiked soil can be used to estimate critical concentration of PAHs inhibiting early establishment of plants in contaminated fields. PMID:19724837

Hong, S H; Kang, B H; Kang, M H; Chung, J W; Jun, W J; Chung, J I; Kim, M C; Shim, S I

2009-09-01

325

Surface flavonoid aglycones in newly studied plant species  

Microsoft Academic Search

Several newly studied species of the Scrophulariaceae, Lamiaceae, and Ranunculaceae spread in Bulgaria have been analyzed for their surface flavonoid profiles. Except Pulsatilla montana (Hope) Rchb. (Ranunculaceae) all taxa now studied accumulated mainly apigenin, luteolin, and it's derivatives. This is the first report for the presence on external flavonoid aglycones in genus Pulsatilla. Quercetin-3?-methyl ether is a new citation for

M. Nikolova; A. Asenov

2006-01-01

326

Invasive Plant Species in Diked vs. Undiked Great Lakes Wetlands  

Microsoft Academic Search

We compared the standing vegetation, seed banks, and substrate conditions in seven pairs of diked and undiked wetlands near the shores of Lake Michigan and Lake Huron, North America. Our analysis tested the null hypothesis that construction of artificial dikes has no effect on the vulnerability of Great Lakes coastal wetlands to non-native and native invasive species. Both the standing

Bradley M. Herrick; Amy T. Wolf

2005-01-01

327

Uptake Kinetics of Arsenic Species in Rice Plants  

PubMed Central

Arsenic (As) finds its way into soils used for rice (Oryza sativa) cultivation through polluted irrigation water, and through historic contamination with As-based pesticides. As is known to be present as a number of chemical species in such soils, so we wished to investigate how these species were accumulated by rice. As species found in soil solution from a greenhouse experiment where rice was irrigated with arsenate contaminated water were arsenite, arsenate, dimethylarsinic acid, and monomethylarsonic acid. The short-term uptake kinetics for these four As species were determined in 7-d-old excised rice roots. High-affinity uptake (0–0.0532 mm) for arsenite and arsenate with eight rice varieties, covering two growing seasons, rice var. Boro (dry season) and rice var. Aman (wet season), showed that uptake of both arsenite and arsenate by Boro varieties was less than that of Aman varieties. Arsenite uptake was active, and was taken up at approximately the same rate as arsenate. Greater uptake of arsenite, compared with arsenate, was found at higher substrate concentration (low-affinity uptake system). Competitive inhibition of uptake with phosphate showed that arsenite and arsenate were taken up by different uptake systems because arsenate uptake was strongly suppressed in the presence of phosphate, whereas arsenite transport was not affected by phosphate. At a slow rate, there was a hyperbolic uptake of monomethylarsonic acid, and limited uptake of dimethylarsinic acid. PMID:11891266

Abedin, Mohammed Joinal; Feldmann, Jorg; Meharg, Andy A.

2002-01-01

328

Evidence of qualitative differences between soil-occupancy effects of invasive vs. native grassland plant species  

USGS Publications Warehouse

Diversified grasslands that contain native plant species are being recognized as important elements of agricultural landscapes and for production of biofuel feedstocks as well as a variety of other ecosystem services. Unfortunately, establishment of such grasslands is often difficult, unpredictable, and highly vulnerable to interference and invasion by weeds. Evidence suggests that soil-microbial "legacies" of invasive perennial species can inhibit growth of native grassland species. However, previous assessments of legacy effects of soil occupancy by invasive species that invade grasslands have focused on single invasive species and on responses to invasive soil occupancy in only a few species. In this study, we tested the hypothesis that legacy effects of invasive species differ qualitatively from those of native grassland species. In a glasshouse, three invasive and three native grassland perennials and a native perennial mixture were grown separately through three cycles of growth and soil conditioning in soils with and without arbuscular mycorrhizal fungi (AMF), after which we assessed seedling growth in these soils. Native species differed categorically from invasives in their response to soil conditioning by native or invasive species, but these differences depended on the presence of AMF. When AMF were present, native species largely had facilitative effects on invasive species, relative to effects of invasives on other invasives. Invasive species did not facilitate native growth; neutral effects were predominant, but strong soil-mediated inhibitory effects on certain native species occurred. Our results support the hypothesis that successful plant invaders create biological legacies in soil that inhibit native growth, but suggest also this mechanism of invasion will have nuanced effects on community dynamics, as some natives may be unaffected by such legacies. Such native species may be valuable as nurse plants that provide cost-effective restoration of soil conditions needed for efficient establishment of diversified grasslands.

Jordan, Nicholas R.; Larson, Diane L.; Huerd, Sheri C.

2011-01-01

329

Using habitat suitability models to target invasive plant species surveys  

USGS Publications Warehouse

Managers need new tools for detecting the movement and spread of nonnative, invasive species. Habitat suitability models are a popular tool for mapping the potential distribution of current invaders, but the ability of these models to prioritize monitoring efforts has not been tested in the field. We tested the utility of an iterative sampling design (i.e., models based on field observations used to guide subsequent field data collection to improve the model), hypothesizing that model performance would increase when new data were gathered from targeted sampling using criteria based on the initial model results. We also tested the ability of habitat suitability models to predict the spread of invasive species, hypothesizing that models would accurately predict occurrences in the field, and that the use of targeted sampling would detect more species with less sampling effort than a nontargeted approach. We tested these hypotheses on two species at the state scale (Centaurea stoebe and Pastinaca sativa) in Wisconsin (USA), and one genus at the regional scale (Tamarix) in the western United States. These initial data were merged with environmental data at 30-m2 resolution for Wisconsin and 1-km2 resolution for the western United States to produce our first iteration models. We stratified these initial models to target field sampling and compared our models and success at detecting our species of interest to other surveys being conducted during the same field season (i.e., nontargeted sampling). Although more data did not always improve our models based on correct classification rate (CCR), sensitivity, specificity, kappa, or area under the curve (AUC), our models generated from targeted sampling data always performed better than models generated from nontargeted data. For Wisconsin species, the model described actual locations in the field fairly well (kappa = 0.51, 0.19, P 2) = 47.42, P < 0.01). From these findings, we conclude that habitat suitability models can be highly useful tools for guiding invasive species monitoring, and we support the use of an iterative sampling design for guiding such efforts.

Crall, Alycia W.; Jarnevich, Catherine S.; Panke, Brendon; Young, Nick; Renz, Mark; Morisette, Jeffrey

2013-01-01

330

Plant Development Affects Arthropod Communities: Opposing Impacts of Species Removal  

Microsoft Academic Search

We examined the hypothesis that developmental phase changes from juvenile to mature growth in plants affect the distribution of common herbivores, which in turn affect the rest of the arthropod community. Using naturally occurring clones of cottonwoods, we compared the arthropod communities found in the mature zones of upper tree canopies, in juvenile zones at the base of mature trees,

Amy Martin Waltz; Thomas G. Whitham

1997-01-01

331

Phytoaccumulation of Lead by Selected Wetland Plant Species  

Microsoft Academic Search

Several anthropogenic activities lead to the production of substantial amounts of aqueous effluents that contain various toxic trace and heavy metals and which pose potential threats to the wild habitat of wetlands. As a part of the remediation of heavy metals, it is necessary to identify some aquatic hyperaccumulator plants. To this end, a greenhouse study was conducted to investigate

Tapan Adhikari; Ajay Kumar; M. V. Singh; A. Subba Rao

2010-01-01

332

Exposure of two upland plant species to acidic fogs.  

PubMed

A system is described for exposing large numbers of plants to acidic fogs. The system allows low volumes of treatment solutions to be provided at particle sizes chiefly in the 5-30 microm range (equivalent to fog/cloud droplets). Plants of Poa alpina L. and Epilobium brunnescens were propagated from material collected in Snowdonia, North Wales and exposed to fog treatments at pH values of 2.5, 3.5, 4.5 and 5.6. There were 3 x 4 h exposures per week which provided a total of 6 mm deposition. Supplementary watering was with pH 4.5 simulated acid rain (24 mm per week). After 21 weeks, there was increased lowering and a greater dry weight for plants of E. brunnescens exposed to the pH 2.5 fog in comparison with other treatments. Also, the plants used assimilated material to form shoots rather than roots. A similar increase in dry weight accumulation in the pH 2.5 treatment was found in P. alpina after 63 weeks but this was not associated with changes in assimilate partitioning. PMID:15092062

Ashenden, T W; Rafarel, C R; Bell, S A

1991-01-01

333

Validation of the ITS2 Region as a Novel DNA Barcode for Identifying Medicinal Plant Species  

PubMed Central

Background The plant working group of the Consortium for the Barcode of Life recommended the two-locus combination of rbcL + matK as the plant barcode, yet the combination was shown to successfully discriminate among 907 samples from 550 species at the species level with a probability of 72%. The group admits that the two-locus barcode is far from perfect due to the low identification rate, and the search is not over. Methodology/Principal Findings Here, we compared seven candidate DNA barcodes (psbA-trnH, matK, rbcL, rpoC1, ycf5, ITS2, and ITS) from medicinal plant species. Our ranking criteria included PCR amplification efficiency, differential intra- and inter-specific divergences, and the DNA barcoding gap. Our data suggest that the second internal transcribed spacer (ITS2) of nuclear ribosomal DNA represents the most suitable region for DNA barcoding applications. Furthermore, we tested the discrimination ability of ITS2 in more than 6600 plant samples belonging to 4800 species from 753 distinct genera and found that the rate of successful identification with the ITS2 was 92.7% at the species level. Conclusions The ITS2 region can be potentially used as a standard DNA barcode to identify medicinal plants and their closely related species. We also propose that ITS2 can serve as a novel universal barcode for the identification of a broader range of plant taxa. PMID:20062805

Chen, Shilin; Yao, Hui; Han, Jianping; Liu, Chang; Song, Jingyuan; Shi, Linchun; Zhu, Yingjie; Ma, Xinye; Gao, Ting; Pang, Xiaohui; Luo, Kun; Li, Ying; Li, Xiwen; Jia, Xiaocheng; Lin, Yulin; Leon, Christine

2010-01-01

334

Subtropical reservoir shorelines have reduced plant species and functional richness compared with adjacent riparian wetlands  

NASA Astrophysics Data System (ADS)

Dam construction has large negative effects on biodiversity in river and riparian ecosystems worldwide. This study aimed to determine whether reservoir shorelines had lower plant species diversity and functional diversity than unregulated or lightly regulated riparian wetlands and to examine the responses of plant diversity and functional traits to reservoir shoreline environmental gradients. We surveyed 146, 44, and 67 plots on reservoir shorelines and in mainstem and tributary riparian wetlands, respectively, in a subtropical river-reservoir system. Species richness, functional richness, evenness, and divergence were calculated to reflect the species and functional diversity of plant communities. Environmental factors including elevation above water level, slope, landform type, substrate, disturbance, and cover were measured. The results showed that both species and functional richness were significantly lower on reservoir shorelines than in riparian wetlands. The relative species number of clonal plants and relative cover of annual plants were both negatively related to slope and elevation. Structural equation modeling and other statistical analyses indicated that most environmental factors had significant effects on species and functional richness on reservoir shorelines but had no significant effect on functional evenness and divergence. Our findings suggest that reservoir shoreline wetlands formed by damming rivers and inundating pre-existing riparian wetlands can be a biodiversity coldspot in regulated rivers at the plot level. Topographic factors are important in determining the plant diversity and vegetation establishment on reservoir shorelines in the Yangtze River basin.

Liu, Wenzhi; Liu, Guihua; Liu, Hui; Song, Yu; Zhang, Quanfa

2013-12-01

335

Rapid Plant Identification Using Species- and Group-Specific Primers Targeting Chloroplast DNA  

PubMed Central

Plant identification is challenging when no morphologically assignable parts are available. There is a lack of broadly applicable methods for identifying plants in this situation, for example when roots grow in mixture and for decayed or semi-digested plant material. These difficulties have also impeded the progress made in ecological disciplines such as soil- and trophic ecology. Here, a PCR-based approach is presented which allows identifying a variety of plant taxa commonly occurring in Central European agricultural land. Based on the trnT-F cpDNA region, PCR assays were developed to identify two plant families (Poaceae and Apiaceae), the genera Trifolium and Plantago, and nine plant species: Achillea millefolium, Fagopyrum esculentum, Lolium perenne, Lupinus angustifolius, Phaseolus coccineus, Sinapis alba, Taraxacum officinale, Triticum aestivum, and Zea mays. These assays allowed identification of plants based on size-specific amplicons ranging from 116 bp to 381 bp. Their specificity and sensitivity was consistently high, enabling the detection of small amounts of plant DNA, for example, in decaying plant material and in the intestine or faeces of herbivores. To increase the efficacy of identifying plant species from large number of samples, specific primers were combined in multiplex PCRs, allowing screening for multiple species within a single reaction. The molecular assays outlined here will be applicable manifold, such as for root- and leaf litter identification, botanical trace evidence, and the analysis of herbivory. PMID:22253728

Staudacher, Karin; Schallhart, Nikolaus; Mitterrutzner, Evi; Steiner, Eva-Maria; Thalinger, Bettina; Traugott, Michael

2012-01-01

336

Screening of radical scavenging activity and polyphenol content of Bulgarian plant species  

PubMed Central

Background: Discovery of new plant species with antioxidant properties is a priority of many research teams. Most of the species included in this study are unstudied for antioxidant properties, but they are taxonomically related to reference plants with well-documented antioxidant activity. Materials and Methods: Free radical scavenging activity of plant extracts was evaluated using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. An aluminum chloride colorimetric method was used for flavonoid determination. The amount of phenolic compounds in the extracts was estimated by using the Folin–Ciocalteu reagent. Results: As a result of screening, it was found that the significant antioxidant properties possess several unstudied until now plant species (Veronica bellidioides L., V. kellereri Deg. et Urm, V. vindobonensis (M. Fisher) M. Fisher, V. beccabunga L., V. rhodopaea L., V. austriaca (Velen.) Degen., Clinopodium vulgare L., Stachysrecta L., Clematis vitalba L., and Xeranthemum annum L.). The antioxidant potential of the new species is comparable to that of reference medicinal plants. Conclusions: The existing data presented here provide new information for antioxidant potential of plant species that have not been traditionally used as medicinal plants. PMID:22224049

Nikolova, Milena

2011-01-01

337

Application of RAPD for molecular characterization of plant species of medicinal value from an arid environment.  

PubMed

The use of highly discriminatory methods for the identification and characterization of genotypes is essential for plant protection and appropriate use. We utilized the RAPD method for the genetic fingerprinting of 11 plant species of desert origin (seven with known medicinal value). Andrachne telephioides, Zilla spinosa, Caylusea hexagyna, Achillea fragrantissima, Lycium shawii, Moricandia sinaica, Rumex vesicarius, Bassia eriophora, Zygophyllum propinquum subsp migahidii, Withania somnifera, and Sonchus oleraceus were collected from various areas of Saudi Arabia. The five primers used were able to amplify the DNA from all the plant species. The amplified products of the RAPD profiles ranged from 307 to 1772 bp. A total of 164 bands were observed for 11 plant species, using five primers. The number of well-defined and major bands for a single plant species for a single primer ranged from 1 to 10. The highest pair-wise similarities (0.32) were observed between A. fragrantissima and L. shawii, when five primers were combined. The lowest similarities (0) were observed between A. telephioides and Z. spinosa; Z. spinosa and B. eriophora; B. eriophora and Z. propinquum. In conclusion, the RAPD method successfully discriminates among all the plant species, therefore providing an easy and rapid tool for identification, conservation and sustainable use of these plants. PMID:21064026

Arif, I A; Bakir, M A; Khan, H A; Al Farhan, A H; Al Homaidan, A A; Bahkali, A H; Al Sadoon, M; Shobrak, M

2010-01-01

338

Linking plant genotype, plant defensive chemistry and mammal browsing in a Eucalyptus species  

Microsoft Academic Search

Summary 1. In the field of plant-herbivore interactions a major focus of research is the import- ance of herbivores as selective agents on the evolution of plant resistance. Evidence to support the role of herbivores as selective agents must demonstrate that the intra- specific variation in plant resistance, and the variation in the plant resistive trait, are under genetic control.

J. M. O'REILLY-WAPSTRA; C. MCARTHUR; B. M. POTTS

2004-01-01

339

Characteristics of heavy metal uptake by plant species with potential for phytoremediation and phytomining  

Microsoft Academic Search

Genetically transformed hairy root cultures were established for a range of plant species and applied in studies of growth and accumulation of heavy metals. Experiments were conducted using liquid nutrient medium containing elevated concentrations of Ni, Cd or Cu. Hairy roots of three hyperaccumulator species were tested for Ni uptake, of these, Alyssum bertolonii accumulated the highest Ni contents in

T. V. Nedelkoska; P. M. Doran

2000-01-01

340

Nitrogen deposition and plant species interact to influence soil carbon stabilization  

E-print Network

species composition in mediating effects of N deposition on soil organic C decomposition and long composition and/or elevated atmospheric CO2 cause high litter lignin inputs to soils. Keywords Carbon isotopes of increased N deposition and plant species composition on long-term soil C sequestration are unknown

Minnesota, University of

341

Variation among plant species in pollutant removal from stormwater in biofiltration systems  

Microsoft Academic Search

Biofiltration systems use vegetation to improve efficiency of pollutant removal from stormwater, but little is known of how plants vary in their capacity to improve biofilter effectiveness. We used a pot trial of 20 Australian species to investigate how species vary in the removal of pollutants from semisynthetic stormwater passing through a soil filter medium. Effluent levels of total suspended

Jennifer Read; Tricia Wevill; Tim Fletcher; Ana Deletic

2008-01-01

342

Reproductive strategies may explain plant tolerance to inundation: A mesocosm experiment using six marsh species  

Microsoft Academic Search

We investigated the impact of inundation duration on sexual and asexual reproduction strategies in six hygrophilic angiosperm species (2 annuals –Ranunculus sardous and Ranunculus ophioglossifolius, 2 rhizomatous –Juncus articulatus and Eleocharis palustris, and 2 stoloniferous species –Glyceria fluitans and Agrostis stolonifera). Plant growth during three inundation durations (natural, +3 weeks, +6 weeks) was assessed in 20 mesocosms. Biomass and reproductive

C. Mony; E. Mercier; A. Bonis; J. B. Bouzillé

2010-01-01

343

In vitro antimycoplasmal activity of six Jordanian medicinal plants against three Mycoplasma species  

Microsoft Academic Search

The in vitro effect of six Jordanian traditional medicine plant methanolic extracts were tested against 32 isolates of Mycoplasma species; Mycoplasma mycoides subsp. mycoides LC (6), Mycoplasma capricolum subsp. capricolum (8) and M. putrefaciens (18), all isolated from either nasal swabs or milk, from sheep and goats in different regions in Jordan. All Mycoplasma species showed susceptibility to Artemisia herba-alba

W. Al-Momani; E. Abu-Basha; S. Janakat; R. A. J. Nicholas; R. D. Ayling

2007-01-01

344

Determinants of plant establishment success in a multispecies introduction experiment with native and alien species  

PubMed Central

Determinants of plant establishment and invasion are a key issue in ecology and evolution. Although establishment success varies substantially among species, the importance of species traits and extrinsic factors as determinants of establishment in existing communities has remained difficult to prove in observational studies because they can be confounded and mask each other. Therefore, we conducted a large multispecies field experiment to disentangle the relative importance of extrinsic factors vs. species characteristics for the establishment success of plants in grasslands. We introduced 48 alien and 45 native plant species at different seed numbers into multiple grassland sites with or without experimental soil disturbance and related their establishment success to species traits assessed in five independent multispecies greenhouse experiments. High propagule pressure and high seed mass were the most important factors increasing establishment success in the very beginning of the experiment. However, after 3 y, propagule pressure became less important, and species traits related to biotic interactions (including herbivore resistance and responses to shading and competition) became the most important drivers of success or failure. The relative importance of different traits was environment-dependent and changed over time. Our approach of combining a multispecies introduction experiment in the field with trait data from independent multispecies experiments in the greenhouse allowed us to detect the relative importance of species traits for early establishment and provided evidence that species traits—fine-tuned by environmental factors—determine success or failure of alien and native plants in temperate grasslands. PMID:23858466

Kempel, Anne; Chrobock, Thomas; Fischer, Markus; Rohr, Rudolf Philippe; van Kleunen, Mark

2013-01-01

345

PLANT ECOLOGY PROJECTS 2009 PROJECT 1: The coexistence of plankton species  

E-print Network

1 PLANT ECOLOGY PROJECTS 2009 PROJECT 1: The coexistence of plankton species In 1999, Jef Huisman & Franjo Weissing published in Nature an article about biodiversity of plankton species, oscillations and chaos, i.e. they formulated a simple population growth model for plankton, growing on resources, where

Utrecht, Universiteit

346

Students' Perception of Plant and Animal Species: A Case Study from Rural Argentina  

ERIC Educational Resources Information Center

Exotic species seriously affect local biodiversity in Argentina. This article investigates how students in San Juan province perceive native and exotic species. With the help of a written questionnaire, 865 students (9-17 years old) were asked to name the plant and animal they liked most, disliked most, and perceived as most useful, and to name…

Nates, Juliana; Campos, Claudia; Lindemann-Matthies, Petra

2010-01-01

347

Effects of sediment type and water level on biomass production of wetland plant species  

Microsoft Academic Search

We investigated how water level and different sediment types affect the growth of wetland plant species. Twelve different species were grown in drained and waterlogged sediments, which represented types normally encountered in wetlands: a mineral sediment from exposed sites, a sediment from a sheltered site rich in labile organic matter and an organic sediment with decomposing litter of Phragmites australis

John P. M. Lenssen; Frank B. J. Menting; Wim H. van der Putten; Cornelis W. P. M. Blom

1999-01-01

348

Edge type defines alien plant species invasions along Pinus contorta burned, highway and clearcut forest edges  

Microsoft Academic Search

Forest edges have been long recognized as the first landscape elements to be invaded by alien plant species in forest ecosystems. However, little is known about the role of forest edge type in invasive species patterns. In the Northern Rocky Mountains of the United States, disturbance-caused forest edges are a common feature in the landscape with anthropogenic (e.g. roadside, clearcut)

Aníbal Pauchard; Paul B. Alaback

2006-01-01

349

Rare, threatened, and endangered plant species southwest Florida and potential OCS activity impacts  

SciTech Connect

This report on rare, threatened, and endangered plants of southwest Florida is a compilation of all species so designated or considered for listing by Federal, State, and private agencies or organizations. Of 274 species in Pinellas, Hillsborough, Manatee, Sarasota, Charlotte, Lee, Collier, and Monroe Counties, 43 occurring in coastal habitats will be most affected by Outer Continental Shelf development.

McCoy, E.D.

1981-11-01

350

Strong Response of an Invasive Plant Species (Centaurea solstitialis L.) to Global4 Environmental Changes5  

E-print Network

#12;1 1 2 3 Strong Response of an Invasive Plant Species (Centaurea solstitialis L.) to Global4 and in combination, can affect the success of a highly invasive plant. We introduced Centaurea26 solstitialis L prevalence in western North America.37 Key words: Centaurea solstitialis (yellow starthistle), climate change

Dukes, Jeffrey

351

Effects of Glacial to Modern CO2 Gradients on Plant Growth, Water Use and Species Composition  

Microsoft Academic Search

Atmospheric CO2 has doubled since the last glaciation. The consequences of this increase on plants has been tested for monocultures and mixed species combinations along CO2 gradient chambers designed for testing effects of rising CO2 on plant performance. Experiments have been conducted in a greenhouse chamber and in a chamber on natural grassland in the field, over a period of

H. Johnson; W. Polley

2002-01-01

352

Loss of the species distinguishing trait among regenerated Bambusa ventricosa McClure plants  

Microsoft Academic Search

All B. ventricosa plants propagated from excised shoot tips displayed loss of the species characteristic bulbous internodes. The plants were obtained by stimulating axillary shoot differentiation, followed by rooting of shoot separates. Cause of the variance has not been attributable to removal of bamboo mosaic virus infection or growth stress. Chimeral tissue seemed to be excluded, since a few regenerants,

Li-Chun Huang; Bau-Lian Huang

1995-01-01

353

Effects of grassland plant species diversity on soil animal food web components  

Microsoft Academic Search

To investigate the feedback of the plant community to the soil food web we set up a greenhouse experiment manipulating both (1) the diversity of a model grassland community, consisting of 43 common plant species of a Central European Arrhenatherion grassland following \\

Alexandru Milcu; Stephan Partsch; Stefan Scheu

354

Accumulation of Cd, Pb and Zn by 19 wetland plant species in constructed wetland.  

PubMed

Uptake and distribution of Cd, Pb and Zn by 19 wetland plant species were investigated with experiments in small-scale plot constructed wetlands, into which artificial wastewater dosed with Cd, Pb and Zn at concentrations of 0.5, 2.0 and 5.0mgl(-1) was irrigated. The results showed that the removal efficiency of Cd, Pb and Zn from the wastewater were more than 90%. Generally, there were tens differences among the 19 plant species in the concentrations and quantity accumulations of the heavy metals in aboveground part, underground part and whole plants. The distribution ratios into aboveground parts for the metals absorbed by plants varied also largely from about 30% to about 90%. All the plants accumulated, in one harvest, 19.85% of Cd, 22.55% of Pb and 23.75% of Zn that were added into the wastewater. Four plant species, e.g. Alternanthera philoxeroides, Zizania latifolia, Echinochloa crus-galli and Polygonum hydropiper, accumulated high amounts of Cd, Pb and Zn. Monochoria vaginalis was capable for accumulating Cd and Pb, Isachne globosa for Cd and Zn, and Digitaria sanguinalis and Fimbristylis miliacea for Zn. The results indicated that the plants, in constructed wetland for the treatment of wastewater polluted by heavy metals, can play important roles for removal of heavy metals through phytoextraction. Selection of plant species for use in constructed wetland will influence considerably removal efficiency and the function duration of the wetland. PMID:17353090

Liu, Jianguo; Dong, Yuan; Xu, Hai; Wang, Deke; Xu, Jiakuan

2007-08-25

355

VARIATION IN GRAZING TOLERANCE AMONG THREE TALLGRASS PRAIRIE PLANT SPECIES1  

Microsoft Academic Search

Three tallgrass prairie plant species, two common perennial forbs (Artemisia ludoviciana and Aster ericoides (Asteraceae)) and a dominant C4 perennial grass (Sorghastrum nutans) were studied under field and greenhouse conditions to evaluate interspecific variation in grazing tolerance (compensatory growth capacity). Adaptation to ungulate grazing was also assessed by comparing defoliation responses of plants from populations with a 25-yr history of

SAID A. DAMHOUREYEH; DAVID C. HARTNETT

356

Species Composition of Bacterial Communities Influences Attraction of Mosquitoes to Experimental Plant Infusions  

Microsoft Academic Search

In the container habitats of immature mosquitoes, catabolism of plant matter and other organic detritus by microbial organisms produces metabolites that mediate the oviposition behavior of Aedes aegypti and Aedes albopictus. Public health agencies commonly use oviposition traps containing plant infusions for monitoring populations of these mosquito species, which are global vectors of dengue viruses. In laboratory experiments, gravid females

Loganathan Ponnusamy; Dawn M. Wesson; Consuelo Arellano; Coby Schal; Charles S. Apperson

2009-01-01

357

Developing a plant-based vole repellent: screening of ten candidate species  

Microsoft Academic Search

Voles are a major pest in orchards and coniferous plantations. Currently, vole control relies primarily on the use of rodenticides and herbicides. Our goal was to identify a plant species that could be used to develop a non-lethal and effective repellent. No-choice feeding trials with prairie voles (Microtus ochrogaster, Wagner) were used to assess the relative ability of 10 plant

Paul D. Curtis; Elizabeth D. Rowland; George L. Good

2002-01-01

358

PHENOTYPIC PLASTICITY AND MECHANICAL STRESS: BIOMASS PARTITIONING AND CLONAL GROWTH OF AN AQUATIC PLANT SPECIES1  

Microsoft Academic Search

Mechanical stresses from wind, current or wave action can strongly affect plant growth and survival. Survival and distribution of species often depend on the plant's capacity to adapt to such stresses, particularly when amplified by climatic variations. Few studies have dealt with plastic adjustments in response to mechanical stress compared to resource stress. We hypothesized that mechanical stress should favor

SARA PUIJALON; GUDRUN BORNETTE

2006-01-01

359

Environmental gradients, plant distribution, and species richness in arctic salt marsh near Prudhoe Bay, Alaska  

Microsoft Academic Search

Spatial patterns of plant cover and species composition in arctic salt marsh and salt affected tundra near Prudhoe Bay, Alaska reflect gradients in elevation, soil conductivity, and soil concentrations of the ions prevalent in seawater. Soil conductivity and soil concentrations of Ca2+, Mg2+, Na+, K+, SO4= and Cl- were significantly related to site elevation, decreasing as elevation increased. Vascular plant

Dale W. Funk; Lynn E. Noel; Adam H. Freedman

2004-01-01

360

Restoration of rocky slopes based on planted gabions and use of drought-preconditioned woody species  

Microsoft Academic Search

The restoration of steep rock faces with shrubs and trees is difficult due to extreme microclimatic and edaphic conditions. In this study, we tested the applicability of free-standing planted gabions to improve the landscape and achieve protection against rockfall, erosion and enhanced surface flow. Furthermore, we analyzed the effect of preconditioning on drought tolerance of several planted species (Ligustrum vulgare,

Barbara Beikircher; Florin Florineth; Stefan Mayr

2010-01-01

361

Plant size, breeding system, and limits to reproductive success in two sister species of Ferocactus (Cactaceae)  

Microsoft Academic Search

Plant reproductive output can be limited by a variety of factors, bothintrinsic and extrinsic. I investigated the reproductive biologies of twospecies of unbranched short-columnar cacti, Ferocactuscylindraceus and F. wislizeni. I recordedfemalereproductive output (flowers produced, fruit set, seeds per fruit and seedmass), plant size and growth, and used hand-pollination experiments todeterminebreeding systems and pollen limitation. In both species, the ability to

Margrit E. McIntosh

2002-01-01

362

Potential of Indigenous Plant Species for the Phytoremediation of Arsenic Contaminated Land in Kurdistan (Iran)  

Microsoft Academic Search

To evaluate the potential of the indigenous plant species for Arsenic (As) phytoremediation, a total of 138 plant samples and 138 soil samples from rooting zones were collected from two As contaminated areas in Kurdistan, western Iran. The areas were the Sari Gunay Gold Mine (SG), and Ali Abad Village (AA). The soil of both areas naturally contains As, with

Zahed Sharifi; Ali Akbar Safari Sinegani; Satar Shariati

2012-01-01

363

Small-scale response of plant species to land-use intensification1 ric Fdoroff  

E-print Network

1 Small-scale response of plant species to land-use intensification1 2 �ric Fédoroff a , Jean, Departamento de12 Ciencias Ambientales, 45071 Toledo, Spain13 14 Abstract15 Plant communities are affected by land-use and landscape heterogeneity and can be used as16 indicators of environmental change. At small

Paris-Sud XI, Université de

364

Zinc Accumulation in Plant Species Indigenous to a Portuguese Polluted Site: Relation with Soil Contamination  

Microsoft Academic Search

The levels of zinc accumulated by roots, stems, and leaves of two plant species, Rubus ulmifoliusand Phragmites australis, indigenous to the banks of a stream in a Portuguese contaminated site were inves- tigated in field conditions. R. ulmifolius, a plant for which studies on phytoremediation potential are scarce, dominated on the right side of the stream, while P. australis proliferated

Ana P. G. C. Marques; Antonio O. S. S. Rangel; Paula M. L. Castro

2007-01-01

365

Plant rhizosphere species-specific stoichiometry and regulation of extracellular enzyme and microbial community structure  

NASA Astrophysics Data System (ADS)

Plant communities affect the activity and composition of soil microbial communities through alteration of the soil environment during root growth; substrate availability through root exudation; nutrient availability through plant uptake; and moisture regimes through transpiration. As a result, positive feedbacks in soil properties can result from alterations in microbial community composition and function in the rhizosphere zone. At the ecosystem-scale, many properties of soil microbial communities can vary between forest stands dominated by different species, including community composition and stoichiometry. However, the influence of smaller individual plants on grassland soils and microbial communities is less well documented. There is evidence to suggest that some plants can modify their soil environment in a manner that favors their persistence. For example, when Bromus tectorum plants invade, soil microbial communities tend to have higher N mineralization rates (in the rhizosphere zone) relative to native plants. If tight linkages between individual plant species and microbial communities inhabiting the rhizosphere exist, we hypothesized that any differences among plant species specific rhizosphere zones could be observed by shifts in: 1) soil -rhizosphere microbial community structure, 2) enzymatic C:N:P acquisition activities, 3) alterations in the soil C chemistry composition in the rhizosphere, and 4) plant - soil - microbial C:N:P elemental stoichiometry. We selected and grew 4 different C3 grasses species including three species native to the Shortgrass Steppe region (Pascopyrum smithii, Koeleria macrantha, and Vulpia octoflora) and one exotic invasive plant species (B. tectorum) in root-boxes that are designed to allow for easy access to the rhizosphere. The field soil was homogenized using a 4mm sieve and mixed 1:1 with sterile sand and seeded as monocultures (24 replicate root - boxes for each species). Plant and soil samples (along with no - plant control soil samples) were collected on day 28, 78, and 148 (N = 4 /sample period/species). Microbial community structure was quantified using the barcoded pyrosequencing protocols. We measured the potential activity of seven hydrolytic soil enzymes to represent the degradation of C, N, and P-rich substrates. Soil microbial C:N biomass responses to specific plant rhizospheres (MBC and MBN) were measured using the chloroform fumigation extraction method followed by DOC & N analysis. Fourier Transform Infrared Spectroscopy was used to assess differences in plant and soil C chemistry. We found that species specific rhizospheres are characteristic of very different soil chemical, edaphic, and microbial properties. These plant species act as gateways that introduce variability into soil C, N, and P ecosystem functional dynamics directly facilitated by rhizosphere - microbe associations. Our results suggest that nutrient stoichiometry within plant species' rhizospheres is a useful tool for identifying intra-ecosystem functional patterns. By identifying what and how specific species rhizospheres differ among the overall plant community, we can better predict how below-ground microbial community function and subsequent ecosystem processes can be influenced by alterations in plant community shifts based on the rhizosphere effects.

Bell, C. W.; Calderon, F.; Pendall, E.; Wallenstein, M. D.

2012-12-01

366

Effect of soil-added cadmium on several plant species  

Microsoft Academic Search

Several species (Andropogon scoparius, Rhus radicans, Rudbeckia hirta, Anemone cylindrica, Monarda fistulosa, Poa pratensis, and Liatris spicata) native to northwestern Indiana were grown from seed in the greenhouse for 6 weeks. An uncontaminated sandy soil was utilized as the substrate with four levels of soil-added Cd. The concentrations added ranged from 0 to 100 ..mu..g Cd\\/g soil and were comparable

L. J. Miles; G. R. Parker

1979-01-01

367

Soil carbon addition affects plant growth in a species-specific way  

Microsoft Academic Search

Summary 1. Restoration of ex-arable land to species-rich habitats has become common practice in Europe as a result of Agri-Environment Regulations. The results, however, are highly variable and often disappointing. Competition from weedy species as a result of high soil inorganic nitrogen levels can negatively affect the establishment and growth of desirable grassland plant species. One method that has been

RENÉ ESCHEN; HEINZ MÜLLER-SCHÄRER; URS SCHAFFNER

2006-01-01

368

Alien plant species favoured over congeneric natives under experimental climate warming in temperate Belgian climate  

Microsoft Academic Search

Climate warming and biological invasions by alien species are two key factors threatening the world’s biodiversity. To date,\\u000a their impact has largely been studied independently, and knowledge on whether climate warming will promote invasions relies\\u000a strongly on bioclimatic models. We therefore set up a study to experimentally compare responses to warming in native and alien\\u000a plant species. Ten congeneric species pairs were

M. Verlinden; I. Nijs

2010-01-01

369

Biotic Interactions Overrule Plant Responses to Climate, Depending on the Species' Biogeography  

PubMed Central

This study presents an experimental approach to assess the relative importance of climatic and biotic factors as determinants of species' geographical distributions. We asked to what extent responses of grassland plant species to biotic interactions vary with climate, and to what degree this variation depends on the species' biogeography. Using a gradient from oceanic to continental climate represented by nine common garden transplant sites in Germany, we experimentally tested whether congeneric grassland species of different geographic distribution (oceanic vs. continental plant range type) responded differently to combinations of climate, competition and mollusc herbivory. We found the relative importance of biotic interactions and climate to vary between the different components of plant performance. While survival and plant height increased with precipitation, temperature had no effect on plant performance. Additionally, species with continental plant range type increased their growth in more benign climatic conditions, while those with oceanic range type were largely unable to take a similar advantage of better climatic conditions. Competition generally caused strong reductions of aboveground biomass and growth. In contrast, herbivory had minor effects on survival and growth. Against expectation, these negative effects of competition and herbivory were not mitigated under more stressful continental climate conditions. In conclusion we suggest variation in relative importance of climate and biotic interactions on broader scales, mediated via species-specific sensitivities and factor-specific response patterns. Our results have important implications for species distribution models, as they emphasize the large-scale impact of biotic interactions on plant distribution patterns and the necessity to take plant range types into account. PMID:25356912

Welk, Astrid; Welk, Erik; Bruelheide, Helge

2014-01-01

370

From plant neighbourhood to landscape scales: how grazing modifies native and exotic plant species richness in grassland  

Microsoft Academic Search

The interactive effect of grazing and soil resources on plant species richness and coexistence has been predicted to vary\\u000a across spatial scales. When resources are not limiting, grazing should reduce competitive effects and increase colonisation\\u000a and richness at fine scales. However, at broad scales richness is predicted to decline due to loss of grazing intolerant species.\\u000a We examined these hypotheses

Josh W. Dorrough; Julian E. Ash; Sarah Bruce; Sue McIntyre

2007-01-01

371

Potential for Using Native Plant Species in Stormwater Wetlands  

Microsoft Academic Search

Spartina pectinata (prairie cordgrass) was grown under five hydroperiods (wet–dry cycles) to determine its potential for use in stormwater wetlands,\\u000a particularly as an alternative to the highly invasive Phalaris arundinacea (an exotic grass). Rhizomes planted in outdoor microcosms grew vigorously in all treatments, namely, weekly flooding in early\\u000a summer, weekly flooding in late summer, flooding every three weeks throughout the

CRISTINA M. BONILLA-WARFORD; JOY B. ZEDLER

2002-01-01

372

Potential for using native plant species in stormwater wetlands.  

PubMed

Spartina pectinata (prairie cordgrass) was grown under five hydroperiods (wet-dry cycles) to determine its potential for use in stormwater wetlands, particularly as an alternative to the highly invasive Phalaris arundinacea (an exotic grass). Rhizomes planted in outdoor microcosms grew vigorously in all treatments, namely, weekly flooding in early summer, weekly flooding in late summer, flooding every three weeks throughout the summer, weekly flooding throughout the summer, and no flooding. Neither the timing nor frequency of 24-hour floods (10-20 cm deep) affected total stem length (grand mean 1003 +/- 188.8 cm per pot, n = 140) or above-ground biomass (46.5 +/- 8.3 g per pot, equivalent to approximately 360 g/m2). However, by late summer, fewer new tillers were found in unflooded microcosms, indicating that vegetative expansion is drought-sensitive. The growth of Spartina plants was further assessed with and without Glyceria striata (a native grass) and Phalaris arundinacea. Glyceria growth was not affected by hydrologic treatment. Glyceria reduced Spartina growth by approximately 11%, suggesting potential as a cover crop that might reduce establishment and growth of Phalaris seedlings. Seeds of Phalaris did not germinate, but branch fragments established where soil was moist from flooding, regardless of the presence of Glyceria. The ability of Spartina to establish vegetatively and grow well under variable water levels leads us to recommend further testing in stormwater wetlands, along with early planting of Glyceria to reduce weed invasions. PMID:11830768

Bonilla-Warford, Cristina M; Zedler, Joy B

2002-03-01

373

Resistance to rust fungi in Lolium perenne depends on within-species variation and performance of the host species in grasslands of different plant diversity  

Microsoft Academic Search

The hypothesis that plant species diversity and genetic variation of the host species decrease the severity of plant diseases\\u000a is supported by studies of agricultural systems, but experimental evidence from more complex systems is scarce. In an experiment\\u000a with grassland communities of varying species richness (1, 2, 4, 8, 16, and 60 species) and functional group richness (1,\\u000a 2, 3,

Christiane Roscher; Jens Schumacher; Oliver Foitzik; Ernst-Detlef Schulze

2007-01-01

374

INTERACTIONS BETWEEN PLANT SPECIES AND EARTHWORM CASTS IN A CALCAREOUS GRASSLAND UNDER ELEVATED CO 2  

Microsoft Academic Search

We tested the hypothesis that the spatial proximity of a plant species to nutrient-rich earthworm casts (e.g., 100% more ammonium and 30% more phosphate than in adjacent soil) is an important determinant of a plant's responsiveness to elevated at- mospheric CO2. In 1995 we mapped the location of both earthworm surface casts and plants in each of 16 1.2-m2 plots

Johann G. Zaller; John A. Arnone

1999-01-01

375

Phytoremediation for soils contaminated by phenanthrene and pyrene with multiple plant species  

Microsoft Academic Search

Purpose  The remediation of soil polluted by polycyclic aromatic hydrocarbons (PAHs) is of great importance due to the persistence\\u000a and carcinogenic properties of PAHs. Phytoremediation has been regarded as a promising alternative among suggested approaches.\\u000a For the establishment of highly effective remediation method and better understanding of the remediation mechanisms by plants,\\u000a the potentials of three plant species and their planting

Shiqiang Wei; Shengwang Pan

2010-01-01

376

Phytotoxicity of biosolids and screening of selected plant species with potential for mercury phytoextraction  

Microsoft Academic Search

Mercury contaminated stockpiles of biosolids (3.5–8.4mgkg?1 Hg) from Melbourne Water's Western Treatment Plant (MW-WTP) were investigated to evaluate the possibility for their phytoremediation. Nine plant species (Atriplex codonocarpa, Atriplex semibaccata, Austrodanthonia caespitosa, Brassica juncea, Brassica napus, Gypsophila paniculata, Sorghum bicolor, Themeda triandra and Trifolium subterraneum) were screened for phytoextraction potential in Hg-contaminated biosolids from MW-WTP. In addition, the same plant

Cristina Lomonte; Augustine I. Doronila; David Gregory; Alan J. M. Baker; Spas D. Kolev

2010-01-01

377

Roles of the reactive oxygen species-generating peroxidase reactions in plant defense and growth induction  

Microsoft Academic Search

Extracellularly secreted plant peroxidases (POXs) are considered to catalyze the generation of reactive oxygen species (ROS) coupled to oxidation of plant hormone indole-3-acetic acid (IAA) and defense-related compounds salicylic acid (SA), aromatic monoamines (AMAs) and chitooligosaccharides (COSs). This review article consists of two parts, which describe H2O2-dependent and H2O2-independent mechanisms for ROS generation, respectively. Recent studies have shown that plant

T. Kawano

2003-01-01

378

Rhizosphere microbial community and its response to plant species and soil history  

Microsoft Academic Search

The plant rhizosphere is a dynamic environment in which many parameters may influence the population structure, diversity\\u000a and activity of the microbial community. Two important factors determining the structure of microbial community present in\\u000a the vicinity of plant roots are plant species and soil type. In the present study we assessed the structure of microbial communities\\u000a in response to four

P. V. Garbeva; J. D. van Elsas; J. A. van Veen

2008-01-01

379

Predicting rarity and decline in animals, plants, and mushrooms based on species attributes and indicator groups  

PubMed Central

In decisions on nature conservation measures, we depend largely on knowledge of the relationship between threats and environmental factors for a very limited number of species groups, with relevant environmental factors often being deduced from the relationship between threat and species traits. But can relationships between traits and levels of threats be identified across species from completely different taxonomic groups; and how accurately do well-known taxonomic groups indicate levels of threat in other species groups? To answer these questions, we first made a list of 152 species attributes of morphological and demographic traits and habitat requirements. Based on these attributes we then grew random forests of decision trees for 1183 species in the 18 different taxonomic groups for which we had Red Lists available in the Netherlands, using these to classify animals, plants, and mushrooms according to their rarity and decline. Finally, we grew random forests for four species groups often used as indicator groups to study how well the relationship between attribute and decline within these groups reflected that relationship within the larger taxonomic group to which these groups belong. Correct classification of rarity based on all attributes was as high as 88% in animals, 85% in plants, and 94% in mushrooms and correct classification of decline was 78% in animals, 69% in plants, and 70% in mushrooms. Vertebrates indicated decline in all animals well, as did birds for all vertebrates and vascular plants for all plants. However, butterflies poorly indicated decline in all insects. Random forests are a useful tool to relate rarity and decline to species attributes thereby making it possible to generalize rarity and decline to a wider set of species groups. Random forests can be used to estimate the level of threat to complete faunas and floras of countries or regions. In regions like the Netherlands, conservation policy based on attributes known to be relevant for the decline to birds, vertebrates or plants will probably also impact all aboveground terrestrial and freshwater macrofauna or macrophytes. PMID:24223278

Musters, C J M; Kalkman, Vincent; van Strien, Arco

2013-01-01

380

Two New Nuclear Isolation Buffers for Plant DNA Flow Cytometry: A Test with 37 Species  

PubMed Central

Background and Aims After the initial boom in the application of flow cytometry in plant sciences in the late 1980s and early 1990s, which was accompanied by development of many nuclear isolation buffers, only a few efforts were made to develop new buffer formulas. In this work, recent data on the performance of nuclear isolation buffers are utilized in order to develop new buffers, general purpose buffer (GPB) and woody plant buffer (WPB), for plant DNA flow cytometry. Methods GPB and WPB were used to prepare samples for flow cytometric analysis of nuclear DNA content in a set of 37 plant species that included herbaceous and woody taxa with leaf tissues differing in structure and chemical composition. The following parameters of isolated nuclei were assessed: forward and side light scatter, propidium iodide fluorescence, coefficient of variation of DNA peaks, quantity of debris background, and the number of particles released from sample tissue. The nuclear genome size of 30 selected species was also estimated using the buffer that performed better for a given species. Key Results In unproblematic species, the use of both buffers resulted in high quality samples. The analysis of samples obtained with GPB usually resulted in histograms of DNA content with higher or similar resolution than those prepared with the WPB. In more recalcitrant tissues, such as those from woody plants, WPB performed better and GPB failed to provide acceptable results in some cases. Improved resolution of DNA content histograms in comparison with previously published buffers was achieved in most of the species analysed. Conclusions WPB is a reliable buffer which is also suitable for the analysis of problematic tissues/species. Although GPB failed with some plant species, it provided high-quality DNA histograms in species from which nuclear suspensions are easy to prepare. The results indicate that even with a broad range of species, either GPB or WPB is suitable for preparation of high-quality suspensions of intact nuclei suitable for DNA flow cytometry. PMID:17684025

Loureiro, João; Rodriguez, Eleazar; Doležel, Jaroslav; Santos, Conceição

2007-01-01

381

Global warming reduces plant reproductive output for temperate multi-inflorescence species on the Tibetan plateau.  

PubMed

• Temperature is projected to increase more during the winter than during the summer in cold regions. The effects of winter warming on reproductive effort have not been examined for temperate plant species. • Here, we report the results of experimentally induced seasonal winter warming (0.4 and 2.4°C increases in growing and nongrowing seasons, respectively, using warmed and ambient open-top chambers in a Tibetan Plateau alpine meadow) for nine indeterminate-growing species producing multiple (single-flowered or multi-flowered) inflorescences and three determinate-growing species producing single inflorescences after a 3-yr period of warming. • Warming reduced significantly flower number and seed production per plant for all nine multi-inflorescence species, but not for the three single-inflorescence species. Warming had an insignificant effect on the fruit to flower number ratio, seed size and seed number per fruit among species. The reduction in seed production was largely attributable to the decline in flower number per plant. The flowering onset time was unaffected for nine of the 12 species. Therefore, the decline in flower production and seed production in response to winter warming probably reflects a physiological response (e.g. metabolic changes associated with flower production). • Collectively, the data indicate that global warming may reduce flower and seed production for temperate herbaceous species and will probably have a differential effect on single- vs multi-inflorescence species. PMID:22591333

Liu, Yinzhan; Mu, Junpeng; Niklas, Karl J; Li, Guoyong; Sun, Shucun

2012-07-01

382

The influence of plant species on the plant/air partitioning coefficients of PCBs and chlorinated benzenes  

SciTech Connect

The plant/air partitioning coefficients (K{sub PA}) of pentachlorobenzene, hexachlorobenzene and 16 PCB congeners were determined in five different grass and herb species common to Central Europe (Lolium multiflorum, Trifolium repens, Plantago lanceolata, Crepis biennis, Achillea millefolium). The measurements were conducted between 5 C and 35 C using a solid phase fugacity meter. Octanol/air partition coefficients (K{sub OA}) were also measured over a similar temperature range. In all cases an excellent linear relationship between log K{sub PA} and log K{sub OA} was observed (r{sup 2} between 0.80 and 0.99). However, while the slope of this relationship was 1 for Lolium multiflorum (ryegrass), in agreement with previous work, the slopes of the log K{sub PA} vs. log K{sub OA} plot were less than 1 for the other 4 species, lying as low as 0.49 for Achillea millefolium (yarrow). Large differences in the enthalpy of phase change (plant/air) were also observed between the different species, but these differences were not related to the differences in the partition coefficients. These observations demonstrate that the contaminant storage properties of plants are variable, and that the lipophilic compartment in some plants is considerably more polar than octanol. This places constraints on the applicability of current models of plant uptake, almost all of which assume that the lipophilic compartment behaves like octanol, and reinforces the need for more research into the contaminant storage properties of plants.

Koemp, P.; McLachlan, M.S. [Univ. of Bayreuth (Germany)

1995-12-31

383

Selenium and Sulfur Accumulation and Soil Selenium Dissipation in Planting of Four Herbaceous Plant Species in Soil Contaminated with Drainage Sediment Rich in Both Selenium and Sulfur  

Microsoft Academic Search

Four selenium (Se) nonaccumulator plant species, including a forage grass species, Tall Fescue (Festuca arundinacea Schreb.), a forage legume species, Alfalfa (Medicago sativa L.), a wetland species, Rush (Juncus tenuis Wild.), and a dry-land alkaline soil species, Saltgrass (Distichlis spicata L.), were grown in soil contaminated by agricultural drainage sediment having elevated levels of Se and sulfur (S). The above-ground

Lin Wu; Xun Guo; Gary S. Bañuelos

2003-01-01

384

Assessment of potential indigenous plant species for the phytoremediation of arsenic-contaminated areas of Bangladesh.  

PubMed

Soil and water contaminated with arsenic (As) pose a major environmental and human health problem in Bangladesh. Phytoremediation, a plant-based technology, may provide an economically viable solution for remediating the As-polluted sites. The use of indigenous plants with a high tolerance and accumulation capacity for As may be a very convenient approach for phytoremediation. To assess the potential of native plant species for phytoremediation, plant and soil samples were collected from four As-contaminated (groundwater) districts in Bangladesh. The main criteria used for selecting plants for phytoremediation were high bioconcentration factors (BCFs) and translocation factors (TFs) of As. From the results of a screening of 49 plant species belonging to 29 families, only one species of fern (Dryopteris filix-mas), three herbs (Blumea lacera, Mikania cordata, and Ageratum conyzoides), and two shrubs (Clerodendrum trichotomum and Ricinus communis) were found to be suitable for phytoremediation. Arsenic bioconcentration and translocation factors > 1 suggest that these plants are As-tolerant accumulators with potential use in phytoextraction. Three floating plants (Eichhornia crassipes, Spirodela polyrhiza, and Azolla pinnata) and a common wetland weed (Monochoria vaginalis) also showed high BCF and TF values; therefore, these plants may be promising candidates for cleaningup As-contaminated surface water and wetland areas. The BCF of Oryza sativa, obtained from As-contaminated districts was > 1, which highlights possible food-chain transfer issues for As-contaminated areas in Bangladesh. PMID:18709925

Mahmud, Rezwanul; Inoue, Naoto; Kasajima, Shin-Ya; Shaheen, Riffat

2008-01-01

385

Profiling mRNAs of two Cuscuta species reveals possible candidate transcripts shared by parasitic plants.  

PubMed

Dodders are among the most important parasitic plants that cause serious yield losses in crop plants. In this report, we sought to unveil the genetic basis of dodder parasitism by profiling the trancriptomes of Cuscuta pentagona and C. suaveolens, two of the most common dodder species using a next-generation RNA sequencing platform. De novo assembly of the sequence reads resulted in more than 46,000 isotigs and contigs (collectively referred to as expressed sequence tags or ESTs) for each species, with more than half of them predicted to encode proteins that share significant sequence similarities with known proteins of non-parasitic plants. Comparing our datasets with transcriptomes of 12 other fully sequenced plant species confirmed a close evolutionary relationship between dodder and tomato. Using a rigorous set of filtering parameters, we were able to identify seven pairs of ESTs that appear to be shared exclusively by parasitic plants, thus providing targets for tailored management approaches. In addition, we also discovered ESTs with sequences similarities to known plant viruses, including cryptic viruses, in the dodder sequence assemblies. Together this study represents the first comprehensive transcriptome profiling of parasitic plants in the Cuscuta genus, and is expected to contribute to our understanding of the molecular mechanisms of parasitic plant-host plant interactions. PMID:24312295

Jiang, Linjian; Wijeratne, Asela J; Wijeratne, Saranga; Fraga, Martina; Meulia, Tea; Doohan, Doug; Li, Zhaohu; Qu, Feng

2013-01-01

386

Profiling mRNAs of Two Cuscuta Species Reveals Possible Candidate Transcripts Shared by Parasitic Plants  

PubMed Central

Dodders are among the most important parasitic plants that cause serious yield losses in crop plants. In this report, we sought to unveil the genetic basis of dodder parasitism by profiling the trancriptomes of Cuscuta pentagona and C. suaveolens, two of the most common dodder species using a next-generation RNA sequencing platform. De novo assembly of the sequence reads resulted in more than 46,000 isotigs and contigs (collectively referred to as expressed sequence tags or ESTs) for each species, with more than half of them predicted to encode proteins that share significant sequence similarities with known proteins of non-parasitic plants. Comparing our datasets with transcriptomes of 12 other fully sequenced plant species confirmed a close evolutionary relationship between dodder and tomato. Using a rigorous set of filtering parameters, we were able to identify seven pairs of ESTs that appear to be shared exclusively by parasitic plants, thus providing targets for tailored management approaches. In addition, we also discovered ESTs with sequences similarities to known plant viruses, including cryptic viruses, in the dodder sequence assemblies. Together this study represents the first comprehensive transcriptome profiling of parasitic plants in the Cuscuta genus, and is expected to contribute to our understanding of the molecular mechanisms of parasitic plant-host plant interactions. PMID:24312295

Wijeratne, Saranga; Fraga, Martina; Meulia, Tea; Doohan, Doug; Li, Zhaohu; Qu, Feng

2013-01-01

387

A Dehydration-Responsive Element Binding (DREB) Transcription Factor from the Succulent Halophyte Salicornia brachiata Enhances Abiotic Stress Tolerance in Transgenic Tobacco.  

PubMed

Dehydration-responsive element binding (DREB) transcription factor (TF) plays a key role for abiotic stress tolerance in plants. Earlier, we have published the isolation and characterisation of an A-2-type SbDREB2A TF from an extreme halophyte Salicornia brachiata. The SbDREB2A protein lacks potential proline (P), glutamic acid (E), serine (S) and threonine (T) (PEST) sequence which is known to act as signal peptide for protein degradation. In this study, SbDREB2A TF was over-expressed in tobacco plants without any modification in polypeptide sequence. Transgenic plants showed better seed germination and growth characteristics in both hyperionic and hyperosmotic stresses. Transgenic plants exhibited higher water content, membrane stability and less electrolyte leakage in stress conditions. The transgenic plants accumulated less Na(+) and higher K(+) than wildtype (WT) plants. The transgenic plants revealed higher chlorophyll content, water use efficiency (WUE) and net photosynthesis rate. Transgenics exhibited higher level of proline and low amount of MDA and H2O2 under stress conditions. The real-time PCR of transgenics showed higher expression of downstream heat shock genes (Hsp18, Hsp26 and Hsp70), TFs (AP2 domain containing TF, HSF2 and ZFP), signalling components (PLC3 and Ca (2+) /calmodulin) and dehydrins (ERD10B, ERD10D and LEA5) under different abiotic stress treatments. PMID:25022621

Gupta, Kapil; Jha, Bhavanath; Agarwal, Pradeep K

2014-12-01

388

Advances in the reintroduction of rare and endangered wild plant species.  

PubMed

Human disturbance and climate change have increased the risk of extinction for rare and endangered wild plant species. One effective way to conserve these rare and endangered species is through reintroduction. In this review, we summarize the advances in wild plant reintroduction from five perspectives: the establishment of reintroduction biology as an important tool for biodiversity conservation; the importance of genetic diversity in reintroduction; reintroduction under global climate change; recruitment limitation in reintroduction; and reintroduction and ecological restoration. In addition, we consider the future of plant reintroduction strategies. PMID:24824586

Ren, Hai; Jian, ShuGuang; Liu, HongXiao; Zhang, QianMei; Lu, HongFang

2014-06-01

389

Comparative studies on plant range size: Linking reproductive and regenerative traits in two Ipomoea species  

NASA Astrophysics Data System (ADS)

Reproductive and regenerative traits associated with colonization and persistence ability may determine plant range size. However, few comparative studies on plant distribution have assessed these traits simultaneously. Pollinator richness and frequency of visits, autonomous self-pollination ability, reproductive output (i.e., reproductive traits), seed bank strategy and seedling density (i.e., regenerative traits) were compared between the narrowly distributed Ipomoea rubriflora O'Donnell (Convolvulaceae) and its widespread congener Ipomoea purpurea (L.) Roth. The narrowly distributed species showed higher ecological specialization to pollinators and lower autonomous self-pollination ability. Frequency of visits, natural seed/ovule ratio and fruit set, and total fruit production did not differ between species. However, the number of seeds produced per fruit was lower in the narrowly distributed species, translating into lower total seed production per plant. Indeed, I. rubriflora formed smaller transient and persistent seed banks and showed lower seedling density than the widespread I. purpurea. These reproductive and regenerative trait results suggest that the narrowly distributed species may have lower colonization and persistence ability than its widespread congener. They further suggest that the negative effects of lower fecundity in the narrowly distributed species might persist in time through the long-lasting effects of total seed production on seed bank size, reducing the species' ability to buffered environmental stochasticity. However, other regenerative traits, such as seed size, and processes such as pre- and post-dispersal seed predation, might modulate the effects of plant fecundity on plant colonization and persistence ability and thus range size.

Astegiano, Julia; Funes, Guillermo; Galetto, Leonardo

2010-09-01

390

Transpiration in seven plant species colonizing a fishpond shore  

Microsoft Academic Search

In 7 species (Eleocharis palustris\\u000a R. Br.,Juncus bufonius L.,Gypsophila muralis L.,Trifolium repens L.,Agrostis stolonifera L.,Potentilla anserina L. andAchillea millefolium L.) growing in a gradient of habitats from aquatic to terrestrial, on a sandy fishpond shore in Southern Bohemia, Czechoslovakia,\\u000a the daily course of transpiration rate and water content was assessed gravimetrically in their cut-off transpiring parts on\\u000a two typical summer

J. Kv?t

1975-01-01

391

Habitat area and climate stability determine geographical variation in plant species range sizes  

PubMed Central

Despite being a fundamental aspect of biodiversity, little is known about what controls species range sizes. This is especially the case for hyperdiverse organisms such as plants. We use the largest botanical data set assembled to date to quantify geographical variation in range size for ? 85 000 plant species across the New World. We assess prominent hypothesised range-size controls, finding that plant range sizes are codetermined by habitat area and long- and short-term climate stability. Strong short- and long-term climate instability in large parts of North America, including past glaciations, are associated with broad-ranged species. In contrast, small habitat areas and a stable climate characterise areas with high concentrations of small-ranged species in the Andes, Central America and the Brazilian Atlantic Rainforest region. The joint roles of area and climate stability strengthen concerns over the potential effects of future climate change and habitat loss on biodiversity. PMID:24119177

Morueta-Holme, Naia; Enquist, Brian J; McGill, Brian J; Boyle, Brad; J?rgensen, Peter M; Ott, Jeffrey E; Peet, Robert K; Simova, Irena; Sloat, Lindsey L; Thiers, Barbara; Violle, Cyrille; Wiser, Susan K; Dolins, Steven; Donoghue, John C; Kraft, Nathan J B; Regetz, Jim; Schildhauer, Mark; Spencer, Nick; Svenning, Jens-Christian

2013-01-01

392

[Decomposition interaction of mixed litter between Chinese fir and various accompanying plant species].  

PubMed

Studies on the decomposition of mixed litter between Chinese fir and 8 accompanying plant species showed that the decomposition of Chinese fir litter was promoted to different degrees by 8 mixed plant species, in which Angiopteris fokiensis had the greatest effect, while Schima superba had certain promotion first, but then, weak inhibition. The order of promotion was Angiopteris fokiensis > Maesa japonica > Ficus simplicissima > Woodwardia japonica > Boehmeria nivea > Castanopsis fargesii > Castanopsis fissa > Dicranopteris dicotoma. Chinese fir litter had a certain inhibition to litter decomposition of Schima superba and Castanopsis fissa, and certain promotion to litter decomposition of Castanopsis fargesii, but the interactions were not significant. There existed an interaction between Chinese fir and some plant species in the course of mixed decomposition. Therefore, rational protection and restoration of understory plant was important to fasten nutrient cycling of Chinese fir plantation ecosystem and to maintain soil fertility. PMID:11758404

Lin, K; Hong, W; Yu, X; Huang, B

2001-06-01

393

Planting six tree species on soda-saline-alkali soil  

Microsoft Academic Search

Populus simonigra, Salix matsudana, Ulmus pumila, Populus nigra, Acer negundo, Fraxinus mandshurica. Tamarix chinensis, Hippophae\\u000a rhammoldes, Syriga onlata were planted on the soda-saline-alkali. The soil had pH 8.5–9.6, salinity 0.1%–0.3%, sodiumionized\\u000a ratio 16%–51% and normality ratio of saline base Na+\\/(Ca+++Mg++)>4. Populus simonigra grows very well on the all kinds of soda-saline-alkali soils except on the alkali sport with the worst

Zhang Yujiang; Liu Peng; Yang Dewei; Ma Chenghui; Liu Gang

1998-01-01

394

Single pollinator species losses reduce floral fidelity and plant reproductive function.  

PubMed

Understanding the functional impacts of pollinator species losses on plant populations is critical given ongoing pollinator declines. Simulation models of pollination networks suggest that plant communities will be resilient to losing many or even most of the pollinator species in an ecosystem. These predictions, however, have not been tested empirically and implicitly assume that pollination efficacy is unaffected by interactions with interspecific competitors. By contrast, ecological theory and data from a wide range of ecosystems show that interspecific competition can drive variation in ecological specialization over short timescales via behavioral or morphological plasticity, although the potential implications of such changes in specialization for ecosystem functioning remain unexplored. We conducted manipulative field experiments in which we temporarily removed single pollinator species from study plots in subalpine meadows, to test the hypothesis that interactions between pollinator species can shape individual species' functional roles via changes in foraging specialization. We show that loss of a single pollinator species reduces floral fidelity (short-term specialization) in the remaining pollinators, with significant implications for ecosystem functioning in terms of reduced plant reproduction, even when potentially effective pollinators remained in the system. Our results suggest that ongoing pollinator declines may have more serious negative implications for plant communities than is currently assumed. More broadly, we show that the individual functional contributions of species can be dynamic and shaped by the community of interspecific competitors, thereby documenting a distinct mechanism for how biodiversity can drive ecosystem functioning, with potential relevance to a wide range of taxa and systems. PMID:23878216

Brosi, Berry J; Briggs, Heather M

2013-08-01

395

Transfer of elements relevant to radioactive waste from soil to five boreal plant species.  

PubMed

In long-term safety assessment models for radioactive waste disposal, uptake of radionuclides by plants is an important process with possible adverse effects in ecosystems. Cobalt-60, (59,63)Ni, (93)Mo, and (210)Pb are examples of long-living radionuclides present in nuclear waste. The soil-to-plant transfer of stable cobalt, nickel, molybdenum and lead and their distribution across plant parts were investigated in blueberry (Vaccinium myrtillus), May lily (Maianthemum bifolium), narrow buckler fern (Dryopteris carthusiana), rowan (Sorbus aucuparia) and Norway spruce (Picea abies) at two boreal forest sites in Eastern Finland. The concentrations of all of the studied elements were higher in roots than in above-ground plant parts showing that different concentration ratios (CR values) are needed for modelling the transfer to roots and stems/leaves. Some significant differences in CR values were found in comparisons of different plant species and of the same species grown at different sites. However, large within-species variation suggests that it is not justified to use different CR values for modelling soil-to-plant transfer of these elements in the different boreal forest plant species. PMID:21190719

Roivainen, Päivi; Makkonen, Sari; Holopainen, Toini; Juutilainen, Jukka

2011-04-01

396

Coevolution between native and invasive plant competitors: implications for invasive species management  

PubMed Central

Invasive species may establish in communities because they are better competitors than natives, but in order to remain community dominants, the competitive advantage of invasive species must be persistent. Native species that are not extirpated when highly invasive species are introduced are likely to compete with invaders. When population sizes and genetic diversity of native species are large enough, natives may be able to evolve traits that allow them to co-occur with invasive species. Native species may also evolve to become significant competitors with invasive species, and thus affect the fitness of invaders. Invasive species may respond in turn, creating either transient or continuing coevolution between competing species. In addition to demographic factors such as population size and growth rates, a number of factors including gene flow, genetic drift, the number of selection agents, encounter rates, and genetic diversity may affect the ability of native and invasive species to evolve competitive ability against one another. We discuss how these factors may differ between populations of native and invasive plants, and how this might affect their ability to respond to selection. Management actions that maintain genetic diversity in native species while reducing population sizes and genetic diversity in invasive species could promote the ability of natives to evolve improved competitive ability.

Leger, Elizabeth A; Espeland, Erin K

2010-01-01

397

Effect of fertiliser application and abandonment on plant species composition of Festuca rubra grassland  

NASA Astrophysics Data System (ADS)

Little is known about the effects of nitrogen (N), phosphorus (P) and potassium (K) application on soil chemical properties and plant species composition of mountain Festuca rubra grasslands. In this study, we aimed to determine whether fertiliser application affects plant species composition and soil properties during periods of management, and whether residual after-effects of fertiliser application can be detected eight years after its use is abandoned. The experiment with unfertilised control, PK treatment and treatments with low and higher level of NPK application under three (intensive management from 1993 to 1997) and two cut management (moderate management from 1997 to 1999) was established in the Jizera Mts. (Czech Republic) on F. rubra meadow and then the experiment was eight years abandoned. Immediately after the introduction of intensive management, a decrease in species richness and diversification of plant species composition occurred. Plant communities which had diversified in different fertiliser treatments persisted under moderately intensive management. The cover of Alopecurus pratensis increased to >50% while the cover of Agrostis capillaris decreased to <5% in NPK treatments during the period of intensive management. Trifolium repens became the dominant species in the PK treatment. Within eight years, under no management, the differences in plant species composition disappeared, species richness decreased and F. rubra, followed by Hypericum maculatum, became dominant in all treatments. The differences in biomass P concentration and plant available P and K concentrations in the soil were still detectable eight years after the last fertiliser application. As shown in this study, moderate application of NPK and consequent abandonment need not generate irreversible changes in species composition of mountain grassland.

Pavl?, Vilém; Gaisler, Jan; Pavl?, Lenka; Hejcman, Michal; Ludvíková, Vendula

2012-11-01

398

Obsolete pesticides and application of colonizing plant species for remediation of contaminated soil in Kazakhstan.  

PubMed

In Kazakhstan, there is a problem of finding ways to clean local sites contaminated with pesticides. In particular, such sites are the deserted and destroyed storehouses where these pesticides were stored; existing storehouses do not fulfill sanitary standards. Phytoremediation is one potential method for reducing risk from these pesticides. Genetic heterogeneity of populations of wild and weedy species growing on pesticide-contaminated soil provides a source of plant species tolerant to these conditions. These plant species may be useful for phytoremediation applications. In 2008-2009 and 2011, we surveyed substances stored in 80 former pesticide storehouses in Kazakhstan (Almaty oblast) to demonstrate an inventory process needed to understand the obsolete pesticide problem throughout the country, and observed a total of 354.7 t of obsolete pesticides. At the sites, we have found organochlorine pesticides residues in soil including metabolites of dichlorodiphenyltrichloroethane and isomers of hexachlorocyclohexane. Twenty-four of the storehouse sites showed pesticides concentrations in soil higher than maximum allowable concentration which is equal to 100 ?g kg(-1) in Kazakhstan. Seventeen pesticide-tolerant wild plant species were selected from colonizing plants that grew into/near the former storehouse's pesticides. The results have shown that colonizing plant annual and biannual species growing on soils polluted by pesticides possess ability to accumulate organochlorine pesticide residues and reduce pesticide concentrations in soil. Organochlorine pesticides taken up by the plants are distributed unevenly in different plant tissues. The main organ of organochlorine pesticide accumulation is the root system. The accumulation rate of organochlorine pesticides was found to be a specific characteristic of plant species and dependent on the degree of soil contamination. This information can be used for technology development of phytoremediation of pesticide-contaminated soils. PMID:22890508

Nurzhanova, Asil; Kalugin, Sergey; Zhambakin, Kabl

2013-04-01

399

Temporal-Spatial Dynamics in Orthoptera in Relation to Nutrient Availability and Plant Species Richness  

PubMed Central

Nutrient availability in ecosystems has increased dramatically over the last century. Excess reactive nitrogen deposition is known to negatively impact plant communities, e.g. by changing species composition, biomass and vegetation structure. In contrast, little is known on how such impacts propagate to higher trophic levels. To evaluate how nitrogen deposition affects plants and herbivore communities through time, we used extensive databases of spatially explicit historical records of Dutch plant species and Orthoptera (grasshoppers and crickets), a group of animals that are particularly susceptible to changes in the C:N ratio of their resources. We use robust methods that deal with the unstandardized nature of historical databases to test whether nitrogen deposition levels and plant richness changes influence the patterns of richness change of Orthoptera, taking into account Orthoptera species functional traits. Our findings show that effects indeed also propagate to higher trophic levels. Differences in functional traits affected the temporal-spatial dynamics of assemblages of Orthoptera. While nitrogen deposition affected plant diversity, contrary to our expectations, we could not find a strong significant effect of food related traits. However we found that species with low habitat specificity, limited dispersal capacity and egg deposition in the soil were more negativly affected by nitrogen deposition levels. Despite the lack of significant effect of plant richness or food related traits on Orthoptera, the negative effects of nitrogen detected within certain trait groups (e.g. groups with limited disperse ability) could be related to subtle changes in plant abundance and plant quality. Our results, however, suggest that the changes in soil conditions (where many Orthoptera species lay their eggs) or other habitat changes driven by nitrogen have a stronger influence than food related traits. To fully evaluate the negative effects of nitrogen deposition on higher trophic levels it is essential to take into account species life-history traits. PMID:23951232

Hendriks, Rob J. J.; Carvalheiro, Luisa G.; Kleukers, Roy M. J. C.; Biesmeijer, Jacobus C.

2013-01-01

400

Plant DNA Barcodes Can Accurately Estimate Species Richness in Poorly Known Floras  

PubMed Central

Background Widespread uptake of DNA barcoding technology for vascular plants has been slow due to the relatively poor resolution of species discrimination (?70%) and low sequencing and amplification success of one of the two official barcoding loci, matK. Studies to date have mostly focused on finding a solution to these intrinsic limitations of the markers, rather than posing questions that can maximize the utility of DNA barcodes for plants with the current technology. Methodology/Principal Findings Here we test the ability of plant DNA barcodes using the two official barcoding loci, rbcLa and matK, plus an alternative barcoding locus, trnH-psbA, to estimate the species diversity of trees in a tropical rainforest plot. Species discrimination accuracy was similar to findings from previous studies but species richness estimation accuracy proved higher, up to 89%. All combinations which included the trnH-psbA locus performed better at both species discrimination and richness estimation than matK, which showed little enhanced species discriminatory power when concatenated with rbcLa. The utility of the trnH-psbA locus is limited however, by the occurrence of intraspecific variation observed in some angiosperm families to occur as an inversion that obscures the monophyly of species. Conclusions/Significance We demonstrate for the first time, using a case study, the potential of plant DNA barcodes for the rapid estimation of species richness in taxonomically poorly known areas or cryptic populations revealing a powerful new tool for rapid biodiversity assessment. The combination of the rbcLa and trnH-psbA loci performed better for this purpose than any two-locus combination that included matK. We show that although DNA barcodes fail to discriminate all species of plants, new perspectives and methods on biodiversity value and quantification may overshadow some of these shortcomings by applying barcode data in new ways. PMID:22096501

Costion, Craig; Ford, Andrew; Cross, Hugh; Crayn, Darren; Harrington, Mark; Lowe, Andrew

2011-01-01

401

Phylogenetic diversity of plants alters the effect of species richness on invertebrate herbivory  

PubMed Central

Long-standing ecological theory proposes that diverse communities of plants should experience a decrease in herbivory. Yet previous empirical examinations of this hypothesis have revealed that plant species richness increases herbivory in just as many systems as it decreases it. In this study, I ask whether more insight into the role of plant diversity in promoting or suppressing herbivory can be gained by incorporating information about the evolutionary history of species in a community. In an old field system in southern Ontario, I surveyed communities of plants and measured levels of leaf damage on 27 species in 38 plots. I calculated a measure of phylogenetic diversity (PSE) that encapsulates information about the amount of evolutionary history represented in each of the plots and looked for a relationship between levels of herbivory and both species richness and phylogenetic diversity using a generalized linear mixed model (GLMM) that could account for variation in herbivory levels between species. I found that species richness was positively associated with herbivore damage at the plot-level, in keeping with the results from several other recent studies on this question. On the other hand, phylogenetic diversity was associated with decreased herbivory. Importantly, there was also an interaction between species richness and phylogenetic diversity, such that plots with the highest levels of herbivory were plots which had many species but only if those species tended to be closely related to one another. I propose that these results are the consequence of interactions with herbivores whose diets are phylogenetically specialized (for which I introduce the term cladophage), and how phylogenetic diversity may alter their realized host ranges. These results suggest that incorporating a phylogenetic perspective can add valuable additional insight into the role of plant diversity in explaining or predicting levels of herbivory at a whole-community scale. PMID:23825795

2013-01-01

402

Are plant species able to keep pace with the rapidly changing climate?  

PubMed

Future climate change is predicted to advance faster than the postglacial warming. Migration may therefore become a key driver for future development of biodiversity and ecosystem functioning. For 140 European plant species we computed past range shifts since the last glacial maximum and future range shifts for a variety of Intergovernmental Panel on Climate Change (IPCC) scenarios and global circulation models (GCMs). Range shift rates were estimated by means of species distribution modelling (SDM). With process-based seed dispersal models we estimated species-specific migration rates for 27 dispersal modes addressing dispersal by wind (anemochory) for different wind conditions, as well as dispersal by mammals (dispersal on animal's coat - epizoochory and dispersal by animals after feeding and digestion - endozoochory) considering different animal species. Our process-based modelled migration rates generally exceeded the postglacial range shift rates indicating that the process-based models we used are capable of predicting migration rates that are in accordance with realized past migration. For most of the considered species, the modelled migration rates were considerably lower than the expected future climate change induced range shift rates. This implies that most plant species will not entirely be able to follow future climate-change-induced range shifts due to dispersal limitation. Animals with large day- and home-ranges are highly important for achieving high migration rates for many plant species, whereas anemochory is relevant for only few species. PMID:23894290

Cunze, Sarah; Heydel, Felix; Tackenberg, Oliver

2013-01-01

403

Are Plant Species Able to Keep Pace with the Rapidly Changing Climate?  

PubMed Central

Future climate change is predicted to advance faster than the postglacial warming. Migration may therefore become a key driver for future development of biodiversity and ecosystem functioning. For 140 European plant species we computed past range shifts since the last glacial maximum and future range shifts for a variety of Intergovernmental Panel on Climate Change (IPCC) scenarios and global circulation models (GCMs). Range shift rates were estimated by means of species distribution modelling (SDM). With process-based seed dispersal models we estimated species-specific migration rates for 27 dispersal modes addressing dispersal by wind (anemochory) for different wind conditions, as well as dispersal by mammals (dispersal on animal's coat – epizoochory and dispersal by animals after feeding and digestion – endozoochory) considering different animal species. Our process-based modelled migration rates generally exceeded the postglacial range shift rates indicating that the process-based models we used are capable of predicting migration rates that are in accordance with realized past migration. For most of the considered species, the modelled migration rates were considerably lower than the expected future climate change induced range shift rates. This implies that most plant species will not entirely be able to follow future climate-change-induced range shifts due to dispersal limitation. Animals with large day- and home-ranges are highly important for achieving high migration rates for many plant species, whereas anemochory is relevant for only few species. PMID:23894290

Cunze, Sarah; Heydel, Felix; Tackenberg, Oliver

2013-01-01

404

Do host plant volatiles influence the diel periodicity of caterpillar foraging of all species attacking the same host plant  

Microsoft Academic Search

Shiojiri et al. reported that host plant (corn) volatiles rather than photoperiod influenced the diel periodicity of larvae foraging behavior in Mythimna separata. We undertook experiments to determine if the same trends were observed in two other noctuid species, M. unipuncta and Spodoptera litura, that also use corn as a host. In the case of Mythimna separata we again observed

Kaori Shiojiri; J. N. McNeil; J. Takabayashi

2011-01-01

405

Using species spectra to evaluate plant community conservation value along a gradient of anthropogenic disturbance.  

PubMed

The aim of this study was to assess the impact of anthropogenic disturbance on the partitioning of plant communities (species spectra) across a landcover gradient of community types, categorizing species on the basis of their biogeographic, ecological, and conservation status. We tested a multinomial model to generate species spectra and monitor changes in plant assemblages as anthropogenic disturbance rise, as well as the usefulness of this method to assess the conservation value of a given community. Herbaceous and arborescent communities were sampled in five Azorean islands. Margins were also sampled to account for edge effects. Different multinomial models were applied to a data set of 348 plant species accounting for differences in parameter estimates among communities and/or islands. Different levels of anthropogenic disturbance produced measurable changes on species spectra. Introduced species proliferated and indigenous species declined, as anthropogenic disturbance and management intensity increased. Species assemblages of relevance other than economic (i.e., native, endemic, threatened species) were enclosed not only in natural habitats, but also in human managed arborescent habitats, which can positively contribute for the preservation of indigenous species outside remnants of natural areas, depending on management strategies. A significant presence of invasive species in margin transects of most community types will contribute to an increase in edge effect that might facilitate invasion. The multinomial model developed in this study was found to be a novel and expedient tool to characterize the species spectra at a given community and its use could be extrapolated for other assemblages or organisms, in order to evaluate and forecast the conservation value of a site. PMID:23224646

Marcelino, José A P; Silva, Luís; Garcia, Patricia V; Weber, Everett; Soares, António O

2013-08-01

406

Differential effects of plant diversity on functional trait variation of grass species  

PubMed Central

Background and Aims Functional trait differences and trait adjustment in response to influences of the biotic environment could reflect niche partitioning among species. In this study, we tested how variation in above-ground plant traits, chosen as indicators for light and nitrogen acquisition and use, differs among taxonomically closely related species (Poaceae) to assess their potential for niche segregation at increasing plant diversity. Methods Traits of 12 grass species were measured in experimental grasslands (Jena Experiment) of varying species richness (from 1 to 60) and presence of particular functional groups (grasses, legumes, tall herbs and small herbs). Key Results Grass species increased shoot and leaf length, investment into supporting tissue (stem mass fraction) and specific leaf area as well as reduced foliar ?13C values with increasing species richness, indicating higher efforts for light acquisition. These species-richness effects could in part be explained by a higher probability of legume presence in more diverse communities. Leaf nitrogen concentrations increased and biomas s : N ratios in shoots decreased when grasses grew with legumes, indicating an improved nitrogen nutrition. Foliar ?15N values of grasses decreased when growing with legumes suggesting the use of depleted legume-derived N, while decreasing ?15N values with increasing species richness indicated a shift in the uptake of different N sources. However, efforts to optimize light and nitrogen acquisition by plastic adjustment of traits in response to species richness and legume presence, varied significantly among grass species. It was possible to show further that trait adjustment of grass species increased niche segregation in more diverse plant communities but that complementarity through niche separation may differ between light and nutrient acquisition. Conclusions The results suggest that even among closely related species such as grasses different strategies are used to cope with neighbours. This lack in redundancy in turn may facilitate complementary resource use and coexistence. PMID:21068024

Gubsch, Marlen; Buchmann, Nina; Schmid, Bernhard; Schulze, Ernst-Detlef; Lipowsky, Annett; Roscher, Christiane

2011-01-01

407

Interspecific Variation of Plant Traits Associated with Resistance to Herbivory Among Four Species of Ficus (Moraceae)  

PubMed Central

• Background and aims To understand the defensive characteristics of interspecies varieties and their responses to herbivory damage, four species of Ficus plants (Ficus altissima, F. auriculata, F. racemosa and F. hispida) were studied. They were similar in life form, but differed in successional stages. Of these, Ficus altissima is a late successional species, F. hispida is a typical pioneer and F. auriculata and F. racemosa are intermediate successional species. We addressed the following questions: (1) What is the difference in plant traits among the four species and are these traits associated with differences in herbivory damage levels? (2) What is the difference in the damage-induced changes among the four species? • Methods Herbivory damage was measured in the field on randomly planted seedlings of the four species of the same age. Defences to herbivory were also tested by feeding leaves of the four species to larvae of Asota caricae in the laboratory. A total of 14 characters such as water content, thickness, toughness, pubescence density on both sides, leaf expansion time, lifetime and the contents of total carbon (C), nitrogen (N), phosphorous (P), potassium (K), magnesium (Mg) and calcium (Ca) were measured. Leaf calcium oxalate crystal (COC) density, total Ca and N content, leaf toughness and height were measured to investigate induced responses to artificial herbivory among the four species. • Key results and conclusions Herbivory damage in the four studied species varied greatly. The pioneer species, F. hispida, suffered the most severe herbivory damage, while the late successional species, F. altissima, showed the least damage. A combination of several characteristics such as high in content of N, Ca and P and low in leaf toughness, lifetime and C : N ratio were associated with increased herbivore damage. The late successional species, F. altissima, might also incorporate induced defence strategies by means of an increase in leaf COC and toughness. PMID:15277244

XIANG, HUI; CHEN, JIN

2004-01-01

408

Ecological implications of reduced pollen deposition in alpine plants: a case study using a dominant cushion plant species.  

PubMed

The reproductive assurance hypothesis states that self-incompatible female plants must produce twice the number of seeds relative to their self-compatible hermaphroditic counterparts to persist in gynodioecious populations. This is a viable life-history strategy, provided that pollination rates are sufficiently high. However, reduced pollination rates in alpine plants are likely due to climate induced plant-pollinator mismatches and general declines in pollinators. Using a gynodioecious population of the dominant plant Silene acaulis (Caryophyllaceae), we tested the reproductive assurance hypothesis and also the stress gradient hypothesis with a series of pollinator exclusion trials and extensive measurements of subsequent reproductive output (gender ratio, plant size, percent fruit-set, fruit weight, seeds per fruit, total seeds, seed weight, and seed germination). The reproductive assurance hypothesis was supported with female plants being more sensitive to and less likely to be viable under reductions in pollination rates. These findings are the first to show that the stress gradient hypothesis is also supported under a gradient of pollen supply instead of environmental limitations. Beneficiary abundance was negatively correlated to percent fruit-set under current pollen supply, but became positive under reduced pollen supply suggesting that there are important plant-plant-pollinator interactions related to reproduction in these alpine plant species. PMID:25075305

Reid, Anya; Hooper, Robyn; Molenda, Olivia; Lortie, Christopher J

2014-01-01

409

Phytotoxicity of sulfamethazine soil pollutant to six legume plant species.  

PubMed

The effect of traces of sulfamethazine (SMZ) in soil (0.01, 0.1, 0.25, 1, 5, 15, and 20 mM) on cellular distribution of cytochrome c oxidase activity, shoot and root growth, and leachate electroconductivity was analyzed in germinating seeds of yellow lupin, pea, lentil, soybean, adzuki bean, and alfalfa. Results showed that a high activity of cytochrome c oxidase in mitochondria correlated with high seed vigor and viability. The appearance of necroses and root decay was associated with a decrease in the activity of mitochondrial cytochrome c oxidase but was accompanied by an increase in cytosolic cytochrome c oxidase activity. A short exposure period of seeds (3 and 6 d) to sulfamethazine did not influence germination. Elongation of roots and stems was more sensitive than germination rate as an indicator of soil contamination by sulfamethazine. Among all tested leguminous plants, yellow lupin was the most reliable bioindicator of SMZ contaminated soil. PMID:20706947

Piotrowicz-Cie?lak, Agnieszka I; Adomas, Barbara; Na?ecz-Jawecki, Grzegorz; Michalczyk, Dariusz J

2010-01-01

410

Plant species of the Central European flora as aliens in Australia Stedoevropsk rostlinn druhy zavlecen do Austrlie  

E-print Network

­482. The Central European flora is an important source pool of plant species introduced to many regions throughout and taxonomy. Across all species, substantially larger numbers of species were introduced between 1840 and 1880 species and 61 grass species present in Central Europe have been introduced to Australia. Differential

Richner, Heinz

411

Stochasticity of species assemblage of canopy trees and understorey plants in a temperate secondary forest created by major disturbances  

Microsoft Academic Search

Detrended canonical correspondence analysis (DCCA) was applied to explore the species assemblage of plants in a temperate secondary forest that was created by major disturbances. The DCCA showed vague relationships between species dominance and environmental factors for canopy tree species even when rare species were excluded from the analysis. For the highest dominant species of the understorey, the scores of

Tsutom Hiura

2001-01-01

412

Alien plants in urban nature reserves: from red-list species to future invaders? 27 Alien plants in urban nature reserves  

E-print Network

Alien plants in urban nature reserves: from red-list species to future invaders? 27 Alien plants 2011 Citation: Jarosík V, Pysek P, KadlecT (2011) Alien plants in urban nature reserves: from red in these protected areas are complicated by high proportions of alien species. We examined which environmental

Kratochvíl, Lukas

413

Seed banks and seed population dynamics of halophytes  

Microsoft Academic Search

In this review I will describe the importance of seed banks and thepopulation dynamics of seeds on the distribution of species in salinehabitats. The main questions being examined in this review include: 1.Does the seed bank represent the flora of the entire salinity gradient or isit restricted to the species in each zonal community? 2. Is the size andspecies composition

Irwin A. Ungar

2001-01-01

414

Bottom-up effects of host-plant species diversity and top-down effects of ants  

E-print Network

to increase plant performance; diversity increased plant growth (but not biomass), and this effect; plant growth; top-down effects 1. INTRODUCTION The consequences of plant species diversity on ecosystem plant growth as well as the abundance and diversity of associated arthropods in grasses, legumes, forbs

Mooney, Kailen A.

415

Phytotoxicity of biosolids and screening of selected plant species with potential for mercury phytoextraction.  

PubMed

Mercury contaminated stockpiles of biosolids (3.5-8.4 mg kg(-1) Hg) from Melbourne Water's Western Treatment Plant (MW-WTP) were investigated to evaluate the possibility for their phytoremediation. Nine plant species (Atriplex codonocarpa, Atriplex semibaccata, Austrodanthonia caespitosa, Brassica juncea, Brassica napus, Gypsophila paniculata, Sorghum bicolor, Themeda triandra and Trifolium subterraneum) were screened for phytoextraction potential in Hg-contaminated biosolids from MW-WTP. In addition, the same plant species were germinated and grown in two other substrates (i.e. potting mix and potting mix spiked with mercury(II)). Growth measurements and the mercury uptake for all three substrates were compared. Some plant species grown in potting mix spiked with mercury(II) grew more vigorously than in the other two substrates and showed higher levels of sulphur in their tissues. These results suggested that the mercury stress activated def