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Fungal assemblages associated with roots of halophytic and non-halophytic plant species vary differentially along a salinity gradient.  


Structure of fungal communities is known to be influenced by host plants and environmental conditions. However, in most cases, the dynamics of these variation patterns are poorly understood. In this work, we compared richness, diversity, and composition between assemblages of endophytic and rhizospheric fungi associated to roots of two plants with different lifestyles: the halophyte Inula crithmoides and the non-halophyte I. viscosa (syn. Dittrichia viscosa L.), along a spatially short salinity gradient. Roots and rhizospheric soil from these plants were collected at three points between a salt marsh and a sand dune, and fungi were isolated and characterized by ITS rDNA sequencing. Isolates were classified in a total of 90 operational taxonomic units (OTUs), belonging to 17 fungal orders within Ascomycota and Basidiomycota. Species composition of endophytic and soil communities significantly differed across samples. Endophyte communities of I. crithmoides and I. viscosa were only similar in the intermediate zone between the salt marsh and the dune, and while the latter displayed a single, generalist association of endophytes, I. crithmoides harbored different assemblages along the gradient, adapted to the specific soil conditions. In the lower salt marsh, root assemblages were strongly dominated by a single dark septate sterile fungus, also prevalent in other neighboring salt marshes. Interestingly, although its occurrence was positively correlated to soil salinity, in vitro assays revealed a strong inhibition of its growth by salts. Our results suggest that host lifestyle and soil characteristics have a strong effect on endophytic fungi and that environmental stress may entail tight plant-fungus relationships for adaptation to unfavorable conditions. PMID:22573239

Maciá-Vicente, Jose G; Ferraro, Valeria; Burruano, Santella; Lopez-Llorca, Luis V



Mucilage and polysaccharides in the halophyte plant species Kosteletzkya virginica: Localization and composition in relation to salt stress  

Microsoft Academic Search

Mucilage is thought to play a role in salinity tolerance in certain halophytic species by regulating water ascent and ion transport. The localization and composition of mucilage in the halophyte Kosteletzkya virginica was therefore investigated. Plants were grown in a hydroponic system in the presence or absence of 100mM NaCl and regularly harvested for growth parameter assessment and mucilage analysis

Michel Edmond Ghanem; Rui-Ming Han; Birgit Classen; Joëlle Quetin-Leclerq; Gregory Mahy; Cheng-Jiang Ruan; Pei Qin; Francisco Pérez-Alfocea; Stanley Lutts



Mucilage and polysaccharides in the halophyte plant species Kosteletzkya virginica: localization and composition in relation to salt stress.  


Mucilage is thought to play a role in salinity tolerance in certain halophytic species by regulating water ascent and ion transport. The localization and composition of mucilage in the halophyte Kosteletzkya virginica was therefore investigated. Plants were grown in a hydroponic system in the presence or absence of 100mM NaCl and regularly harvested for growth parameter assessment and mucilage analysis with the gas liquid chromatography method. NaCl treatment stimulated shoot growth and biomass accumulation, had little effect on shoot and root water content, and reduced leaf water potential (Psi(w)), osmotic potential (Psi(s)) as well as stomatal conductance (g(s)). Mucilage increased in shoot, stems and roots in response to salt stress. Furthermore, changes were also observed in neutral monosaccharide components. Levels of rhamnose and uronic acid increased with salinity. Staining with a 0.5% alcian blue solution revealed the presence of mucopolyssacharides in xylem vessels and salt-induced mucilaginous precipitates on the leaf abaxial surface. Determination of ion concentrations showed that a significant increase of Na(+) and a decrease of K(+) and Ca(2+) simultaneously occurred in tissues and in mucilage under salt stress. Considering the high proportion of rhamnose and uronic acid in stem mucilage, we suggest that the pectic polysaccharide could be involved in Na(+) fixation, though only a minor fraction of accumulated sodium appeared to be firmly bound to mucilage. PMID:19962213

Edmond Ghanem, Michel; Han, Rui-Ming; Classen, Birgit; Quetin-Leclerq, Joëlle; Mahy, Gregory; Ruan, Cheng-Jiang; Qin, Pei; Pérez-Alfocea, Francisco; Lutts, Stanley



The Reference Genome of the Halophytic Plant Eutrema salsugineum  

PubMed Central

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.

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



The effects of salinity, crassulacean acid metabolism and plant age on the carbon isotope composition of Mesembryanthemum crystallinum L., a halophytic C 3 CAM species  

Microsoft Academic Search

The carbon isotope composition of the halophyte Mesembryanthemum crystallinum L. (Aizoaceae) changes when plants are exposed to environmental stress and when they shift from C3 to crassulacean acid metabolism (CAM). We examined the coupling between carbon isotope composition and photosynthetic pathway by subjecting plants of different ages to salinity and humidity treatments. Whole shoot ?13C values became less negative in

Klaus Winter; Joseph A. M. Holtum



The effects of salinity, crassulacean acid metabolism and plant age on the carbon isotope composition of Mesembryanthemum crystallinum L., a halophytic C(3)-CAM species.  


The carbon isotope composition of the halophyte Mesembryanthemum crystallinum L. (Aizoaceae) changes when plants are exposed to environmental stress and when they shift from C(3) to crassulacean acid metabolism (CAM). We examined the coupling between carbon isotope composition and photosynthetic pathway by subjecting plants of different ages to salinity and humidity treatments. Whole shoot delta(13)C values became less negative in plants that were exposed to 400 mM NaCl in the hydroponic solution. The isotopic change had two components: a direct NaCl effect that was greatest in plants still operating in the C(3) mode and decreased proportionally with increasing levels of dark fixation, and a second component related to the degree of CAM expression. Ignoring the presumably diffusion-related NaCl effect on carbon isotope ratios results in an overestimation of nocturnal CO(2) gain in comparison to an isotope versus nocturnal CO(2) gain calibration established previously for C(3) and CAM species grown under well-watered conditions. It is widely taken for granted that the shift to CAM in M. crystallinum is partially under developmental control and that CAM is inevitably expressed in mature plants. Plants, cultivated under non-saline conditions and high relative humidity (RH) for up to 63 days, maintained diel CO(2) gas-exchange patterns and delta(13)C values typical of C(3) plants. However, a weak CAM gas-exchange pattern and an increase in delta(13)C value were observed in non-salt-treated plants grown at reduced RH. These observations are consistent with environmental control rather than developmental control of the induction of CAM in mature M. crystallinum under non-saline conditions. PMID:15968514

Winter, Klaus; Holtum, Joseph A M



Molecular and functional comparisons of the vacuolar Na+/H+ exchangers originated from glycophytic and halophytic species.  


A novel vacuolar Na+/H+ exchanger, CgNHX1, was cloned from a halophytic species Chenopodium glaucum by using reverse transcriptase-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) technique. Sequence alignment and phylogenetic analysis of 22 NHX genes from GenBank as well as the new CgNHX1 gene indicate that NHX genes shared a great degree of similarity, regardless of their glycophytic or halophytic origin. Expression of the CgNHX1 gene was induced by NaCl and peaked at 400 mmol/L NaCl. Overexpression of NHX1 genes in rice enhanced their tolerance to salt stress. However, there is no significant difference in salt tolerance among the transgenic rice plants overexpressing the NHX1 genes from either glycophytic or halophytic species. The Na+ content of both the wild type (WT) and transgenic plants increased when exposed to 50 and 100 mmol/L NaCl, and the Na+ concentration in transgenic plants was marginally higher than that of WT. Our data demonstrate that the overexpression of the NHX1 gene from either glycophytic or halophytic species resulted in the enhanced tolerance to salt stress at a similar level, suggesting that NHX gene per se might not be the reason accounting for the difference in salt tolerance between glycophytes and halophytes. PMID:18257135

Li, Jin-yao; He, Xiao-wei; Xu, Li; Zhou, Jie; Wu, Ping; Shou, Hui-xia; Zhang, Fu-chun



Kosteletzkya virginica, a halophytic species with potential for agroecotechnology in Jiangsu Province, China  

Microsoft Academic Search

Kosteletzkya virginica (L.) Presl. is a perennial dicot halophytic species, that grows in brackish portions of coastal tidal marshes of the mid-Atlantic and southeastern United States. New saline mudflats have been increasing every year in Northern Jiangsu, China. In 1993, we introduced K. virginica (L.) into China from the Halophyte Biotechnology Center (University of Delaware, USA) as a potential species

Zhenxiang He; Chengjiang Ruan; Pei Qin; Denise M Seliskar; John L Gallagher



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


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



Fungal diversity and plant growth promotion of endophytic fungi from six halophytes in Suncheon Bay.  


Endophytic fungi were isolated from roots of six halophytes in Suncheon Bay. The endophytic fungi of 35 species isolated from halophytes were identified by internal transcribed spacer (ITS) containing the ITS1, 5.8s, and ITS2 regions. All fungal strains were analyzed to diversity at the genus level. Fungal culture filtrates (FCF) of endophytic fungi were treated to Waito-c rice (WR) seedling for plant growth-promoting verification. It was confirmed that fungal strain Sj-2-2 provided plant growth promotion (PGP) to WR seedling. Then, PGP of Suaeda japonica was confirmed by treating culture filtrate of Sj-2-2. As a result, it was verified that culture filtrate of Sj-2-2 had more advanced PGP than positive control when treated to S. japonica. The secondary metabolites involved in culture filtrate of Sj-2-2 were identified by HPLC and GC-MS SIM analysis. The presence of physiologically bioactive gibberellins (GAs) and other inactive GAs in culture filtrate of Sj-2-2 was detected. The molecular analysis of sequences of Sj-2-2 showed the similarity to Penicillium sp. of 99% homology. The PGP of Sj-2-2 as well as symbiosis between endophytic fungi and halophytes growing naturally in salt marsh was confirmed. Sj-2-2 was identified as a new fungal strain producing GAs by molecular analysis of sequences. Consequently, the Sj-2-2 fungal strain was named as Penicillium sp. Sj-2-2. In this study, the diversity of endophytic fungi isolated from roots of halophytes in salt marsh and the PGP of a new gibberellin-producing fungal strain were confirmed. PMID:23124347

You, Young-Hyun; Yoon, Hyeokjun; Kang, Sang-Mo; Shin, Jae-Ho; Choo, Yeon-Sik; Lee, In-Jung; Lee, Jin-Man; Kim, Jong-Guk



Characteristics of seed germination in five non-halophytic Chinese desert shrub species  

Microsoft Academic Search

The effects of temperature, NaCl, and polyethylene glycol (PEG)-6000 on the seed germination of five non-halophytic Chinese desert shrub species were investigated. The minimum temperature of germination was 10°C for all species, and the maximum temperature varied among species from 25 to 35°C. Isotonic solutions of NaCl and PEG caused different effects on seed germination in all five species. When

Kazuo Tobe; Liping Zhang; Guoyu Yu Qiu; Hideyuki Shimizu; Kenji Omasa



Bromide Tolerance in Plants: A Case Study on Halophytes of Indian Coast  

Microsoft Academic Search

The uptake of bromide and the effect of its accumulation on growth of some marshy halophytic species of Indian coast have been investigated. The species selected for this study are Salicornia brachiata, Suaeda nudiflora and Salvadora persica which were grown with NaBr solution along with other essential nutrients. The growth in S. brachiata, S. nudiflora and S. persica was more

Mallampati S. Reddy; Manish P. Joshi; Sunil P. Dave; Subbarayappa Adimurthy; Venkataramakrishna S. Susarla; Aditya S. Mehta; Peddi V. Subba Rao; Muppala P. Reddy; Gadde Ramachandraiah



Sulphide tolerance in coastal halophytes  

Microsoft Academic Search

The effect of sulphide on the growth of several species of salt-marsh plants was investigated. Relative growth rates were significantly reduced in two upper-marsh species, Festuca rubra and Atriplex patula, and in the lower-marsh species Puccinellia maritima. However the growth of Salicornia europaea, a species frequently associated with sulphide-containing sediments, was unaffected. In a separate experiment the wide ranging halophyte

D. C. Havill; A. Ingold; J. Pearson



Transformation of a CAM plant, the facultative halophyte Mesembryanthemum crystallinum by Agrobacterium tumefaciens  

Microsoft Academic Search

This study is the first to demonstrate that a foreign DNA can be delivered into cells of facultative halophyte crassulacean\\u000a acid metabolism (CAM) plant, Mesembryanthemum crystallinum L. with Agrobacterium tumefaciens. This plant can be induced to\\u000a change from C3 to CAM by drought and various stresses, and is a good model to study the environment stress on metabolism not\\u000a only

Ken Ishimaru



Potential of salt-accumulating and salt-secreting halophytic plants for recycling sodium chloride in human urine in bioregenerative life support systems  

NASA Astrophysics Data System (ADS)

This study addresses the possibility of growing different halophytic plants on mineralized human urine as a way to recycle NaCl from human wastes in a bioregenerative life support system (BLSS). Two halophytic plant species were studied: the salt-accumulating Salicornia europaea and the salt-secreting Limonium gmelinii. During the first two weeks, plants were grown on Knop's solution, then an average daily amount of urine produced by one human, which had been preliminarily mineralized, was gradually added to the experimental solutions. Nutrient solutions simulating urine mineral composition were gradually added to control solutions. NaCl concentrations in the stock solutions added to the experimental and control solutions were 9 g/L in the first treatment and 20 g/L in the second treatment. The mineralized human urine showed some inhibitory effects on S. europaea and L. gmelinii. The biomass yield of experimental plants was lower than that of control ones. If calculated for the same time period (120 d) and area (1 m 2), the amount of sodium chloride taken up by S. europaea plants would be 11.7 times larger than the amount taken up by L. gmelinii plants (486 g/m 2 vs. 41 g/m 2). Thus, S. europaea is the better choice of halophyte for recycling sodium chloride from human wastes in BLSS.

Tikhomirova, N. A.; Ushakova, S. A.; Kudenko, Yu. A.; Gribovskaya, I. V.; Shklavtsova, E. S.; Balnokin, Yu. V.; Popova, L. G.; Myasoedov, N. A.; Gros, J.-B.; Lasseur, Ch.



In vitro culture, plant regeneration and clonal behaviour of Sesuvium portulacastrum (L.) L.: a prospective halophyte.  


An efficient plant regeneration protocol using axillary shoots of the salt accumulator halophyte, Sesuvium portulacastrum (L.) L. was established and in vitro responses of six Sesuvium clones were studied. The shoot and root induction responses to cytokinins and auxins in clone MH (Maharashtra) were concentration specific. Significantly the highest number of shoots, average shoot elongation and percent shoot regeneration per explant were observed on MS medium supplemented with 40 ?M 2-isopentenyl adenine (2iP) followed by 20 ?M benzyladenine (BA). Higher cytokinin (60 ?M), however, inhibited shoot induction and shoot length. The lower concentrations (5 or 10 ?M) of ?-napthaleneacetic acid (NAA) proved more effective for root induction, number of roots and average root length. Well-developed plantlets were successfully hardened and established in the field with more than 85 % survival rate. In vitro response of six Sesuvium clones cultured on MS + 20 ?M BA revealed higher multiplication rate in clone MH and KA (Karnataka, India) compared to other clones. The results offer the prospect of selecting clones of this species with characteristics desirable for utilization and/or restoration in specific ecological zones. PMID:23572968

Lokhande, Vinayak Haribhau; Nikam, Tukaram Dayaram; Ghane, Savliram Goga; Suprasanna, Penna



Use of halophytic plants for recycling NaCl in human liquid waste in a bioregenerative life support system  

NASA Astrophysics Data System (ADS)

The purpose of this work was to develop technology for recycling NaCl containing in human liquid waste as intrasystem matter in a bioregenerative life support system (BLSS). The circulation of Na+ and Cl- excreted in urine is achieved by inclusion of halophytes, i.e. plants that naturally inhabit salt-rich soils and accumulate NaCl in their organs. A model of Na+ and Cl- recycling in a BLSS was designed, based on the NaCl turnover in the human-urine-nutrient solution-halophytic plant-human cycle. The study consisted of (i) selecting a halophyte suitable for inclusion in a BLSS, and (ii) determining growth conditions supporting maximal Na+ and Cl- accumulation in the shoots of the halophyte growing in a nutrient solution simulating mineralized urine. For the selected halophytic plant, Salicornia europaea, growth rate under optimal conditions, biomass production and quantities of Na+ and Cl- absorbed were determined. Characteristics of a plant production conveyor consisting of S.europaea at various ages, and allowing continuity of Na+ and Cl- turnover, were estimated. It was shown that closure of the NaCl cycle in a BLSS can be attained if the daily ration of fresh Salicornia biomass for a BLSS inhabitant is approximately 360 g.

Balnokin, Yurii; Nikolai, Myasoedov; Larisa, Popova; Alexander, Tikhomirov; Sofya, Ushakova; Christophe, Lasseur; Jean-Bernard, Gros



An inland and a coastal population of the Mediterranean xero-halophyte species Atriplex halimus L. differ in their ability to accumulate proline and glycinebetaine in response to salinity and water stress  

Microsoft Academic Search

Soil salinity and drought compromise water uptake and lead to osmotic adjustment in xero-halophyte plant species. These important environmental constraints may also have specific effects on plant physiology. Stress-induced accumulation of osmocompatible sol- utes was analysed in two Tunisian populations of the Mediteranean shrub Atriplex halimus L.—plants origi- nating from a salt-affected coastal site (Monastir) or from a non-saline semi-arid

Abir Ben Hassine; Michel Edmond Ghanem; Sadok Bouzid; Stanley Lutts



Seasonal changes in the levels of compatible osmolytes in three halophytic species of inland saline vegetation in Hungary.  


Seasonal changes in the leaf concentration of compatible osmolytes were investigated in three halophytic species (Lepidium crassifolium, Camphorosma annua and Limonium gmelini subsp. hungaricum) native to a salty-sodic grassland. The investigated species were shown to accumulate both carbohydrate- and amino acid-derived osmolytes. The leaf tissues of C. annua (Chenopodiaceae) preferentially stored glycine betaine and pinitol, while in L. gmelini (Plumbaginaceae) beta-alanine betaine, choline-O-sulphate, and pinitol were accumulated. In the leaves of L. crassifolium (Brassicaceae) a very high amount of proline, associated with a high level of soluble carbohydrates was found. Not only the biochemical nature of the osmolyte, but also the seasonal pattern of osmolyte accumulation showed significant species-specific fluctuations. In addition, the cellular levels of the observed osmolytes changed with the growth period and according to the environmental parameters. The highest concentrations of osmolytes were found in March, when low temperatures, hypoxic conditions and high salt concentrations were the main constraints to plant growth. The high structural diversity of osmolytes combined with their multifunctionality and the seasonal flexibility of the metabolism in plants facing multiple stresses is discussed. PMID:12756919

Murakeözy, Eva P; Nagy, Zoltán; Duhazé, Claire; Bouchereau, Alain; Tuba, Zoltán



Stable hydrogen-isotope analysis of methyl chloride emitted from heated halophytic plants  

NASA Astrophysics Data System (ADS)

Stable isotope techniques are increasingly applied to study atmospheric budgets of methyl halides. Here we use compound specific thermal conversion isotope ratio mass spectrometry to measure the stable hydrogen isotope values of methyl chloride (?HCl) released thermally from dried leaves of halophyte plants collected from different geographical locations. We developed an automated purification and pre-concentration unit to enable measurement of ?HCl from samples (100 ml) when mixing ratios were as low as 1 ppmv. Even though this is considerably higher than normal atmospheric mixing ratios this unit enabled measurement of the ?2H values of CH3Cl released during heating of samples at temperatures ranging from 30 to 300 °C. No substantial changes of ?HCl values were observed over this temperature range. However, the ?HCl values of all plants examined were strongly depleted (-178 ± 34‰) relative to the ?2H values of their modelled meteoric water, but differ only by 1-50‰ from those observed for their methoxyl groups. Our results indicate that plant methoxyl groups are an important precursor of the methyl group for CH3Cl thermally emitted from lyophilised and homogenized dry halophyte leaves. Furthermore, the thermal reaction producing CH3Cl did not show a substantial kinetic hydrogen isotope fractionation between CH3Cl and precursor methoxyl groups over the temperature range investigated. Moreover, we found a moderate linear correlation (R2 = 0.37) for the relationship between ?HCl values released from halophytes and the ?2H values of modelled precipitation at their geographical locations. As CH3Cl emissions from terrestrial vegetation, including senescent and dry plants and biomass burning, are considered to provide a substantial fraction of the global emissions our findings are important when establishing a global hydrogen isotope model for atmospheric CH3Cl.

Greule, Markus; Huber, Stefan G.; Keppler, Frank



North American halophytes: Potential use in animal husbandry  

Microsoft Academic Search

\\u000a North America is rich in halophyte plants with over 200 distinct species occurring in coastal and inland regions. They are\\u000a not a single taxonomic group but represent many different taxa and growth forms. Emphasis has shifted from studying halophyte\\u000a ecology and physiology to a serious attempt to utilize them in farming systems. Promising results have been obtained from\\u000a preliminary studies

E. P. Glenn; J. J. Riley; R. S. Swingle; C. U. Mota; M. C. Watson; V. R. Squires


Differential effects of sodium salts on the germination of a native halophytic species from South America: Prosopis strombulifera (Lam.) Benth  

Microsoft Academic Search

Prosopis strombulifera is a halophytic shrub frequently found in the salinized areas of central Argentina. Interactions between\\u000a temperature, ionic and osmotic components of salinity, and seed germination in this species are discussed in this chapter.\\u000a Besides the osmotic effect, specific ion effects of salts play an important role in seed germination causing toxicity to the\\u000a embryo. In saline soils where

Virginia M. Luna; Analía S. Llanes; Laura R. Sosa; Mariana A. Reginato; Herminda E. Reinoso


Effect of sodium chloride on the response of the halophyte species Sesuvium portulacastrum grown in mannitol-induced water stress  

Microsoft Academic Search

Sesuvium portulacastrum is a halophytic species well adapted to salinity and drought. In order to evaluate the physiological impact of salt on water\\u000a deficit-induced stress response, we cultivated seedlings for 12 days, in the presence or absence of 100 mmol l?1 NaCl, on a nutrient solution containing either 0 mmol l?1 or 25 mmol l?1 mannitol. Mannitol-induced water stress reduced growth, increased the root\\/shoot ratio, and led

Inès Slama; Tahar Ghnaya; Dorsaf Messedi; Kamel Hessini; Nahla Labidi; Arnould Savoure; Chedly Abdelly



Adaptive Mechanisms of Halophytes in Desert Regions  

Microsoft Academic Search

Plants growing in desert regions have to face a number of environmental adversaries such as high temperature, soil salinity\\u000a and water stress due to low precipitation. Halophytes are among the successful plants that grow in desert saline regions.\\u000a Halophytes use many different strategies to survive under these conditions. Some halophytes seeds can germinate in the presence\\u000a of high salinity. Seeds

D. J. Weber


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



Kosteletzkya virginica, an agroecoengineering halophytic species for alternative agricultural production in China's east coast: Ecological adaptation and benefits, seed yield, oil content, fatty acid and biodiesel properties  

Microsoft Academic Search

Kosteletzkya virginica, a perennial halophyte, is native to the American salt marsh. It was introduced into China as a potential species to improve tideland and develop ecologically sound saline agriculture. The experimental results in the fields over 10 years indicated that K. virginica adapts excellently to the tidal flat habitats in China's east coast, with multiple ecobenefits such as landscape

C.-J. Ruan; H. Li; Y.-Q. Guo; P. Qin; J. L. Gallagher; D. M. Seliskar; S. Lutts; G. Mahy



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


Influence of biological, environmental and technical factors on phenolic content and antioxidant activities of Tunisian halophytes.  


Halophyte ability to withstand salt-triggered oxidative stress is governed by multiple biochemical mechanisms that facilitate retention and/or acquisition of water, protect chloroplast functioning, and maintain ion homeostasis. Most essential traits include the synthesis of osmolytes, specific proteins, and antioxidant molecules. This might explain the utilization of some halophytes as traditional medicinal and dietary plants. The present study aimed at assessing the phenolic content and antioxidant activities of some Tunisian halophytes (Cakile maritima, Limoniastrum monopetalum, Mesembryanthemum crystallinum, M. edule, Salsola kali, and Tamarix gallica), depending on biological (species, organ and developmental stage), environmental, and technical (extraction solvent) factors. The total polyphenol contents and antioxidant activities (DPPH and superoxide radicals scavenging activities, and iron chelating and reducing powers) were strongly affected by the above-cited factors. Such variability might be of great importance in terms of valorising these halophytes as a source of naturally secondary metabolites, and the methods for phenolic and antioxidant production. PMID:18940702

Ksouri, Riadh; Megdiche, Wided; Falleh, Hanen; Trabelsi, Nejla; Boulaaba, Mondher; Smaoui, Abderrazak; Abdelly, Chedly



Seed germination, growth, and osmotic adjustment in response to NaCl in a rare succulent halophyte from southeastern Spain  

Microsoft Academic Search

In this paper, some issues of the autoecology of Halocnemum strobilaceum (a rare succulent halophyte that occurs in southeastern Spain) are examined, particularly the germination process and the\\u000a first stages of plant development. In regards to germination, this species shows the general pattern of halophytes under increased\\u000a salt stress (reduced germination and germination rate). What stands out is the extreme

Juan A. Pujol; José F. Calvo; Luis Ramírez-Díaz



Water relations of the epidermal bladder cells of the halophytic species Mesembryanthemum crystallinum : Direct measurements of hydrostatic pressure and hydraulic conductivity  

Microsoft Academic Search

Water exchange between the bladder cells of stems of the halophytic species Mesembryanthemum crystallinum and the subepidermal cortical cell layers was determined by direct cell turgor pressure measurements using a pressure probe. Treating the system bladder cell\\/subepidermal cortex as two homogeneous elastic compartments the hydraulic conductivity, Lp, of the barrier separating both compartments was found to be Lp=2·10-6 cm ·s-1·bar-1.

Ernst Steudle; Ulrich Lfittge; Ulrich Zimmermann



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



[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].  


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



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


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

Microsoft Academic Search

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\\u000a homeostasis regulation. Isolates obtained from P. strombulifera were compared genotypically by BOX-polymerase chain reaction, grouped according to similarity, and identified by amplification\\u000a and partial sequences of 16S

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



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


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



Overview of problems and prospects for utilizing halophytes as a resource for livestock and for rehabilitation of degraded lands  

Microsoft Academic Search

\\u000a Halophytes are defined as plant species growing naturally in saline habitats. Their role and potential are discussed under\\u000a seven main headings: land rehabilitation, as irrigated crops using saline water as feed for livestock, as medicinal plants,\\u000a as fuelwoods, as shade and shelter and for sequestration of carbon dioxide. Prospects and problems are discussed.

Victor R. Squires


Salt stress induced differential proteome and metabolome response in the shoots of Aeluropus lagopoides (Poaceae), a halophyte C(4) plant.  


A proteomic approach was used to identify proteins affected by salt in the halophyte C(4) plant Aeluropus lagopoides (Poaceae) in an attempt to understand the mechanism of salt tolerance. Plants were treated with 450 mM NaCl for 10 days, and proteins were then extracted from the shoots and separated by two-dimensional polyacrylamide gel electrophoresis. A total of 1805 protein spots were detected, of which 39 were up-regulated and 44 were down-regulated by treatment with NaCl. Metabolism-related proteins were up-regulated, whereas photosynthesis-related proteins were down-regulated. Dose-dependence studies showed that the up-regulation continued at NaCl concentrations above 450 mM for defense-related proteins alone. Western blot analysis confirmed the down-regulation of RuBisCO LSU and RuBisCO SSU and severe down-regulation of RuBisCO activase. The activity of glyoxalase I increased with increasing NaCl concentration. Metabolome studies indicated up-regulation of amino acids and down-regulation of tricarboxylic acid cycle-related metabolites. These studies suggest that up-regulation of energy formation, amino acid biosynthesis, C(4) photosynthesis, and detoxification are the main strategies for salt tolerance in A. lagopoides. PMID:20397718

Sobhanian, Hamid; Motamed, Nasrin; Jazii, Ferdous Rastgar; Nakamura, Takuji; Komatsu, Setsuko



A salt-inducible chloroplastic monodehydroascorbate reductase from halophyte Avicennia marina confers salt stress tolerance on transgenic plants.  


Plant growth and productivity are adversely affected by various abiotic stress factors. In our previous study, we used Avicennia marina, a halophytic mangrove, as a model plant system for isolating genes functioning in salt stress tolerance. A large scale random EST sequencing from a salt stressed leaf tissue cDNA library of one month old A. marina plants resulted in identification of a clone showing maximum homology to Monodehydroascorbate reductase (Am-MDAR). MDAR plays a key role in regeneration of ascorbate from monodehydroascorbate for ROS scavenging. In this paper, we report the cellular localization and the ability to confer salt stress tolerance in transgenic tobacco of this salt inducible Am-MDAR. A transit peptide at the N-terminal region of Am-MDAR suggested that it encodes a chloroplastic isoform. The chloroplastic localization was confirmed by stable transformation and expression of the Am-MDAR-GFP fusion protein in tobacco. Transgenic tobacco plants overexpressing Am-MDAR survived better under conditions of salt stress compared to untransformed control plants. Assays of enzymes involved in ascorbate-glutathione cycle revealed an enhanced activity of MDAR and ascorbate peroxidase whereas the activity of dehyroascorbate reductase was reduced under salt stressed and unstressed conditions in Am-MDAR transgenic lines. The transgenic lines showed an enhanced redox state of ascorbate and reduced levels of malondialdehyde indicating its enhanced tolerance to oxidative stress. The results of our studies could be used as a starting point for genetic engineering of economically important plants tolerant to salt stress. PMID:20600571

Kavitha, Kumaresan; George, Suja; Venkataraman, Gayatri; Parida, Ajay



Responses of chlorophyll fluorescence parameters of the facultative halophyte and C3-CAM intermediate species Mesembryanthemum crystallinum to salinity and high irradiance stress.  


Mesembryanthemum crystallinum L. (Aizoaceae) is a facultative annual halophyte and a C(3)-photosynthesis/crassulacean acid metabolism intermediate species currently used as a model plant in stress physiology. Both salinity and high light irradiance stress are known to induce CAM in this species. The present study was performed to provide a diagnosis of alterations at the photosystem II level during salinity and irradiance stress. Plants were subjected for up to 13 days to either 0.4M NaCl salinity or high irradiance of 1000 micromol m(-2)s(-1), as well as to both stress factors combined (LLSA=low light plus salt; HLCO=high light of 1000 micromol m(-2)s(-1), no salt; HLSA=high light plus salt). A control of LLCO=low light of 200 micromol m(-2)s(-1), no salt was used. Parameters of chlorophyll a fluorescence of photosystem II (PSII) were measured with a pulse amplitude modulated fluorometer. HLCO and LLSA conditions induced a weak degree of CAM with day/night changes of malate levels (Deltamalate) of approximately 12mM in the course of the experiment, while HLSA induced stronger CAM of Deltamalate approximately 20 mM. Effective quantum yield of PSII, DeltaF/F'(m), was only slightly affected by LLSA, somewhat reduced during the course of the experiment by HLCO and clearly reduced by HLSA. Potential quantum efficiency of PSII, F(v)/F(m), at predawn times was not affected by any of the conditions, always remaining at 0.8, showing that there was no acute photoinhibition. During the course of the days HL alone (HLCO) also did not elicit photoinhibition; salt alone (LLSA) caused acute photoinhibition which was amplified by the combination of the two stresses (HLSA). Non-photochemical, NPQ, quenching remained low (<0.5) under LLCO, LLSA and HLCO and increased during the course of the experiment under HLSA to 1-2. Maximum apparent photosynthetic electron transport rates, ETR(max), declined during the daily courses and were reduced by LLSA and to a similar extent by HLSA. It is concluded that M. crystallinum expresses effective stress tolerance mechanisms but photosynthetic capacity is reduced by the synergistic effects of salinity and light irradiance stress combined. PMID:16781797

Broetto, Fernando; Monteiro Duarte, Heitor; Lüttge, Ulrich



Halophytes--an emerging trend in phytoremediation.  


Halophytic plants are of special interest because these plants are naturally present in environments characterized by an excess of toxic ions, mainly sodium and chloride. Several studies have revealed that these plants may also tolerate other stresses including heavy metals based on the findings that tolerance to salt and to heavy metals may, at least partly, rely on common physiological mechanisms. In addition, it has been shown that salt-tolerant plants may also be able to accumulate metals. Therefore, halophytes have been suggested to be naturally better adapted to cope with environmental stresses, including heavy metals compared to salt-sensitive crop plants commonly chosen for phytoextraction purposes. Thus, potentially halophytes are ideal candidates for phytoextraction orphytostabilization of heavy metal polluted soils and moreover of heavy metal polluted soils affected by salinity. Some halophytes use excretion processes in order to remove the excess of salt ions from their sensitive tissues and in some cases these glandular structures are not always specific to Na+ and Cl- and other toxic elements such as cadmium, zinc, lead, or copper are accumulated and excreted by salt glands or trichomes on the surface of the leaves--a novel phytoremediation process called "phytoexcretion". Finally, the use of halophytes has also been proposed for soil desalination through salt accumulation in the plant tissue or dissolution of soil calcite in the rhizosphere to provide Ca2+ that can be exchanged with Na+ at cation exchange sites. PMID:21972564

Manousaki, Eleni; Kalogerakis, Nicolas


Plant pathogenic Pseudomonas species  

Microsoft Academic Search

In the current taxonomy, plant pathogenic Pseudomonas species are restricted to rRNA group I organisms belonging to the Gamma subclass of Proteobacteria. Currently, about 21 validly described plant pathogenic Pseudomonas species are known. The most important species is P. syringae with more than 50 described pathovars. The pathovar concept is confusing and the taxonomy of P. syringae needs revision. P.

Monica Höfte; PAUL DE VOS


Enhanced salt stress tolerance of rice plants expressing a vacuolar H+ -ATPase subunit c1 (SaVHAc1) gene from the halophyte grass Spartina alterniflora Löisel.  


The physiological role of a vacuolar ATPase subunit c1 (SaVHAc1) from a halophyte grass Spartina alterniflora was studied through its expression in rice. The SaVHAc1-expressing plants showed enhanced tolerance to salt stress than the wild-type plants, mainly through adjustments in early stage and preparatory physiological responses. In addition to the increased accumulation of its own transcript, SaVHAc1 expression led to increased accumulation of messages of other native genes in rice, especially those involved in cation transport and ABA signalling. The SaVHAc1-expressing plants maintained higher relative water content under salt stress through early stage closure of the leaf stoma and reduced stomata density. The increased K(+) /Na(+) ratio and other cations established an ion homoeostasis in SaVHAc1-expressing plants to protect the cytosol from toxic Na(+) and thereby maintained higher chlorophyll retention than the WT plants under salt stress. Besides, the role of SaVHAc1 in cell wall expansion and maintenance of net photosynthesis was implicated by comparatively higher root and leaf growth and yield of rice expressing SaVHAc1 over WT under salt stress. The study indicated that the genes contributing toward natural variation in grass halophytes could be effectively manipulated for improving salt tolerance of field crops within related taxa. PMID:22284568

Baisakh, Niranjan; RamanaRao, Mangu V; Rajasekaran, Kanniah; Subudhi, Prasanta; Janda, Jaroslav; Galbraith, David; Vanier, Cheryl; Pereira, Andy



Comparative estimation of use potentialities of salt-accumulating and salt-eliminating halophytes for inclusion of NaCl contained in human mineralized urine in BLSS's mass exchange  

Microsoft Academic Search

Comparative potentialities of different halophytes' cultivation on a human mineralized urine containing NaCl with the aim of this salt inclusion into the intrasystem BLSS mass exchange were investigated. Two halophyte species were studied namely, salt-accumulating (Salicornia europaea) and salt-eliminating (Limonium gmelinii). During the first two vegetation weeks the plants had been grown on the Knop solution; then a daily norm

Natalia Tikhomirova; Sofya Ushakova; Yurii Kudenko; Illiada Griboskaya; Ekaterina Shklavtsova; Yurii Balnokin; Larissa Popova; Nikolay Myasoedov; Jean-Bernard Gros; Christophe Lasseur




Microsoft Academic Search

Halophytic plants are of special interest since these plants are naturally present in environments characterized by an excess of toxic ions, mainly sodium and chloride. Several studies have revealed that these plants may also tolerate other stresses including heavy metals based on the findings that tolerance to salt and to heavy metals may, at least partly, rely on common physiological

Eleni Manousaki; Nicolas Kalogerakis



Salinity-induced changes in protein expression in the halophytic plant Nitraria sphaerocarpa.  


Salinity is a major abiotic stress that inhibits plant growth and development. Plants have evolved complex adaptive mechanisms that respond to salinity stress. However, an understanding of how plants respond to salinity stress is far from being complete. In particular, how plants survive salinity stress via alterations to their intercellular metabolic networks and defense systems is largely unknown. To delineate the responses of Nitraria sphaerocarpa cell suspensions to salinity, changes in their protein expression patterns were characterized by a comparative proteomic approach. Cells that had been treated with 150 mM NaCl for 1, 3, 5, 7, or 9 days developed several stress-related phenotypes, including those affecting morphology and biochemical activities. Of ~1100 proteins detected in 2-DE gel patterns, 130 proteins showed differences in abundance with more than 1.5-fold when cells were stressed by salinity. All but one of these proteins was identified by MS and database searching. The 129 spots contained 111 different proteins, including those involved in signal transduction, cell rescue/defense, cytoskeleton and cell cycle, protein folding and assembly, which were the most significantly affected. Taken together, our results provide a foundation to understand the mechanism of salinity response. PMID:22728773

Chen, Jinhui; Cheng, Tielong; Wang, Pengkai; Liu, Weidong; Xiao, Jiao; Yang, Yunqiang; Hu, Xiangyang; Jiang, Zeping; Zhang, Shougong; Shi, Jisen



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



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



Plant responses to heterogeneous salinity: growth of the halophyte Atriplex nummularia is determined by the root-weighted mean salinity of the root zone  

PubMed Central

Soil salinity is generally spatially heterogeneous, but our understanding of halophyte physiology under such conditions is limited. The growth and physiology of the dicotyledonous halophyte Atriplex nummularia was evaluated in split-root experiments to test whether growth is determined by: (i) the lowest; (ii) the highest; or (iii) the mean salinity of the root zone. In two experiments, plants were grown with uniform salinities or horizontally heterogeneous salinities (10–450mM NaCl in the low-salt side and 670mM in the high-salt side, or 10mM NaCl in the low-salt side and 500–1500mM in the high-salt side). The combined data showed that growth and gas exchange parameters responded most closely to the root-weighted mean salinity rather than to the lowest, mean, or highest salinity in the root zone. In contrast, midday shoot water potentials were determined by the lowest salinity in the root zone, consistent with most water being taken from the least negative water potential source. With uniform salinity, maximum shoot growth was at 120–230mM NaCl; ~90% of maximum growth occurred at 10mM and 450mM NaCl. Exposure of part of the roots to 1500mM NaCl resulted in an enhanced (+40%) root growth on the low-salt side, which lowered root-weighted mean salinity and enabled the maintenance of shoot growth. Atriplex nummularia grew even with extreme salinity in part of the roots, as long as the root-weighted mean salinity of the root zone was within the 10–450mM range.

Bazihizina, Nadia




Microsoft Academic Search

The coastal and near coastal habitats of Karachi, Pakistan are characterized by dominant stands of perennial halophytes like Aeluropus lagopoides, Desmostachya bipinnata, Haloxylon stocksii and Suaeda fruticosa. Experiments were carried out to investigate comparative effects of NaCl and seasalt salinity on both rate and final seed germination of these species. Salinity tolerance range of halophytes varied among species and also




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


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



Investigations of adaptation mechanisms of different halophytes types in different soil salinity conditions (Southern Central Siberia, Russia)  

NASA Astrophysics Data System (ADS)

High salt concentration in the soil is one of the limiting factors affecting plant growth and development. However, there are plants that are physiologically adapted to high salts concen-trations -halophytes. Studies of halophytes reveals mechanisms of adaptation to this factor. Investigations were conducted in the steppe zone of Southern Central Siberia (Russia, Khaka-sia), nearest coastal zone of the Lake Kurinka. The work was carried on route and stationary methods. As a results was conducted about 100 geobotanical descriptions, was defined species composition, covering, vertical and horizontal structure of plant communities, the productivity of above ground dry phytomass. As a result of field work was identified various types of plant communities, that are located on soils with a salinity degree are 0,2 -7,16 g / l. Type of saline -sulfate-sodium. Suaeda plant communities was located in the meadow-saline soil (soil salinity degree 5 -7 g / l). The dominant is euhalophyte Suaeda linifolia Pall. and subdominant is glycohalophyte Puccinellia tenuissima. A plant community has two layers. Total covering is 50 -55During the study period (2004 -2009), the change was observed in the soil salinity degree in the range of 2.27 -7.16 g / l. The plan community productivity varied from 99 to 201 g/m2 by years of research. Also was noted that the salt amount in the plants biomass varies depending on the type of halophyte. In the cells of euhalophyte Suaeda linifolia the salt amount was 10-35The investigation noted that relations between the main photosynthetic pigments (chlorophylls and carotenoids) have changes depending on the type of halophyte. Thus, in typical glycohalophyte Puccinellia tenuissima, Elytrigia repens and Phragmites australis chlorophyll content remained relatively high during the summer period and were 0,74, 0,61 and 0,53

Slyusar, Natalia; Pechurkin, Nickolay


Evidence for a Large and Sustained Clycolytic Flux to Lactate in Anoxic Roots of Some Members of the Halophytic Genus Limonium  

Microsoft Academic Search

Soil salinity and anaerobiosis often occur together. lhis led us to investigate th6 fermentative metabolism in roots of species from the halophytic genus Limonium (Plumbaginaceae). Root segments from hypoxically induced plants were incubated for 8 h under strict anoxia in the presence of (U-'4C)glucose. In three species (Limon- ium latifolium, L. nashii, and L. humile), the pattern of 14C-labeled end

Jean Rivoal; Andrew D. Hanson


Comparative estimation of use potentialities of salt-accumulating and salt-eliminating halophytes for inclusion of NaCl contained in human mineralized urine in BLSS's mass exchange  

NASA Astrophysics Data System (ADS)

Comparative potentialities of different halophytes' cultivation on a human mineralized urine containing NaCl with the aim of this salt inclusion into the intrasystem BLSS mass exchange were investigated. Two halophyte species were studied namely, salt-accumulating (Salicornia europaea) and salt-eliminating (Limonium gmelinii). During the first two vegetation weeks the plants had been grown on the Knop solution; then a daily norm of the human mineralized urine was gradually added in the experiment solutions. During vegetation the model solutions simulating the urine mineral composition were gradually added in the control solutions. The NaCl concentration in the experiment and control solutions of the first treatment was 9 g/l and that of the second treatment was 20 g/l. The mineralized human urine exposed some inhibitory action on Salicornia europaea and Limonium gmelinii plants. The experiment plants' productivity was lower in comparison with the control. As far as Limonium gmelinii appears to be a perennial plant the growth rate and productivity of this halophyte species was signifi- cantly lower in comparison with Salicornia europaea. Na content in Salicornia europaea plants was higher in comparison with sodium amount emitted by Limonium gmelinii. Consequently Salicornia europaea appears to be a more perspective halophyte for its further use in BLSS aiming at involvement of sodium chloride contained in human liquid wastes in intrasystem mass exchange.

Tikhomirova, Natalia; Ushakova, Sofya; Kudenko, Yurii; Griboskaya, Illiada; Shklavtsova, Ekaterina; Balnokin, Yurii; Popova, Larissa; Myasoedov, Nikolay; Gros, Jean-Bernard; Lasseur, Christophe


Vivipary in coastal cacti: a potential reproductive strategy in halophytic environments.  


Vivipary, the germination of seeds within the fruit prior to abscission from the maternal plant, is an important event in plants. Two main types of vivipary are known in vascular plants: true vivipary and pseudovivipary. In crop grasses, pseudovivipary is an undesirable character as it results in lower yields. To date, vivipary in the Cactaceae has been reported for less than 20 species, most of which are cultivated. Here, we report viviparous (cryptoviviparous-a subcategory of true vivipary) cacti in nature in members of the tribes Cacteae and Pachycereeae (subfamily Cactoideae). We present four species inhabiting coastal plains in areas subject to periodic flooding, namely, Ferocactus herrerae, Stenocereus alamosensis, S. thurberi, and Pachycereus schottii. These species from localities in northwestern Mexico had viviparous fruits and offspring in different stages of development. A potential trend in the data indicates that the overall proportion of viviparous plants is higher in coastal flooding areas relative to halophytic, nonflooding areas. In our view, vivipary is a reproductive strategy that has evolved to provide a more efficient mechanism favoring germination and new avenues for survival by contributing to population maintenance and short-distance dispersal on halophytic substrates. PMID:21636523

Cota-Sánchez, J Hugo; Reyes-Olivas, Alvaro; Sánchez-Soto, Bardo



Seaweeds and halophytes to remove carbon from the atmosphere  

SciTech Connect

The utility industry and other interested parties have investigated strategies to mitigate the buildup of atmospheric CO{sub 2}. One option that has been considered is the planting of trees on a massive scale to absorb carbon through photosynthesis. A dilemma of using tree plantations, however, is that they might occupy land that will be needed for food production or other needs for an expected doubling of human population in the tropical regions. We evaluated seaweeds and salt-tolerant terrestrial plants (halophytes) to be grown on the coastal shelves and salt deserts of the world as possible alternatives to tree plantations. An estimated 1.3 {times} 10{sup 6} km{sup 2} of continental shelf and 1.3 {times} 10{sup 6} km{sup 2} of salt desert may be usable for seaweed and halophyte plantations. The production rates of managed seaweed and halophyte plantings are similar to managed tree plantations. Seaweeds and halophytes could conceivably absorb 10--20% of annual fossil fuel carbon emissions through biomass production, similar to estimates made for tree plantations. Present costs of halophyte biomass production are similar to costs of tree biomass production, whereas seaweed biomass is much more expensive to produce using existing technologies. Storage of seaweed carbon might be accomplished by allowing it to enter the sediment detritus chain whereas halophyte carbon might be sequestered in the soil, or used as biomass fuel. As has been concluded for reforestation, these saline biomass crops could at best help delay rather than solve the carbon dioxide build-up problem. 1 fig., 13 tabs.

Glenn, E.P.; Kent, K.J.; Thompson, T.L.; Frye, R.J. (Arizona Univ., Tucson, AZ (USA). Environmental Research Lab.)



Conservation of tropical plant species  

Technology Transfer Automated Retrieval System (TEKTRAN)

This book is designed to provide a review of the methods and current status of conservation of many tropical plant species. Future perspectives of conservation of tropical species will also be discussed. The section on methods covers the range of conservation techniques, in situ, seed banking, in vi...


An overview of the halophytes in Turkey  

Microsoft Academic Search

Nearly 4.3 million ha of agricultural land in Turkey are degraded, out of which 1.5 million ha are arid and 2.8 million ha\\u000a saline-alkaline. Plant diversity studies show that these areas include 300 halophytic taxa, belonging to 150 genera and 40\\u000a families. The dominant families are Poaceae (16.6%), Chenopodiaceae (14.0%), Asteraceae (12.0%), and Fabaceae (7.6%), while\\u000a the dominant genera with

Aykut Guvensen; Guven Gork; Munir Ozturk


Role of model plant species.  


The use of model or reference species has played a major role in furthering detailed understanding of mechanisms and processes in the plant kingdom over the past 25 years. Species which have been adopted as models for dicotyledons and monocotyledons include arabidopsis and rice and more recently brachy-podium,Such models are diploids, have few and small chromosomes, well developed genetics, rapid life cycles, are easily transformed and have extensive sets of technical resources and databases curated by international resource centres. The study of crop genomics today is deeply rooted in earlier studies on model species. Genomes of model species share reasonable genetic synteny with key crop plants which facilitates the discovery of genes and association of genes with phenotypes. While some mechanisms and processes are conserved across the plant kingdom and so can be revealed by studies on any model species,others have diverged during evolution and so are revealed by studying only a closely related model species.Examples of processes that are conserved across the plant kingdom and others that have diverged and therefore need to be understood by studying a more closely related model species are described. PMID:19347660

Flavell, Richard



Evidence for bioaccumulation of PAHs within internal shoot tissues by a halophytic plant artificially exposed to petroleum-polluted sediments.  


Polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants of natural and anthropic origins. Despite their poor water solubility, they can be taken up and bioaccumulated by plants. This study was aimed at determining whether the PAHs present in sediments artificially polluted by heavy fuel oil are transferred to shoots of a coastal and edible plant, Salicornia fragilis Ball et Tutin. Bioaccumulation was quantified after a one-week exposure to sediments polluted with 0.2%, 2% and 20% fuel oil (w/w) and over a six-week monitoring at 0.2%. Quantification by GC-MS of PAH amounts in plants and sediments evidenced a bioaccumulation in the shoots by a soil-to-plant transfer through the root system. This bioaccumulation depended on the duration of exposure and on the substratum contamination. PAHs distributions in plants and sediments looked alike with a predominance of low- and medium-weight hydrocarbons. Moreover, high-weight PAHs were also detected in the upper part of plants. PMID:16527326

Meudec, A; Dussauze, J; Deslandes, E; Poupart, N



Responses of halophytes to high salinities and low water potentials.  


The effects of nonsaline polyethylene glycol (PEG)-6000 and saline seawater solutions of comparable osmotic potential on the concentrations of organic solutes and inorganic ions in the tissues of halophytes (Plantago maritima L., Triglochin maritima L., Limonium vulgare Mill., Halimione portulacoides (L.) Aell) have been investigated. Studies were made to determine whether high salinities induce specific ion effects that are absent in plants grown in nonsaline solutions of comparable osmotic potential. Over-all, the responses of each species to the two different treatments (seawater or PEG) are similar; the accumulation of organic solutes (compatible osmotica) in tissues is primarily correlated with a decrease in the osmotic potential of culture solutions. Depending on the species, sorbitol, proline, reducing sugars, quaternary ammonium compounds, and alpha-amino nitrogen accumulate in tissues as the water potential of the tissues falls. Within a species there are differences in the concentrations of inorganic ions and organic solutes between roots and shoots of plants grown at high salinities or at high concentrations of PEG. PMID:16661119

Jefferies, R L; Rudmik, T; Dillon, E M



Microsatellite DNA loci from the typical halophyte Thellungiella salsuginea (Brassicaceae)  

Microsoft Academic Search

Thellungiella\\u000a salsuginea (Brassiaceae) is a typical halophyte which can tolerate extreme cold, drought, and salinity. In order to understand the adaptive\\u000a evolution of this species in the arid habitats, it is important to know its genetic structure. In this study, 17 polymorphic\\u000a microsatellite loci were isolated and characterized from an enrichment genomic library of this species. We further assessed\\u000a the

Dahai Gao; Qian Wang; Yuxia Wu; Haiyan Xu; Qiushi Yu; Jianquan Liu



Comparative Studies on the Sodium, Potassium, and Chloride Relations of a Wild Halophytic and a Domestic Salt-Sensitive Tomato Species 1  

PubMed Central

In long-term experiments with differentially salinized nutrient solutions, plants of Lycopersicon esculentum Mill cv. Walter failed at Na+ concentrations of 200 millimolar or more but tolerated K+ concentrations of that magnitude. The behavior of the wild, salt-tolerant Lycopersicon cheesmanii (Hook) C. H. Mull., accession number 1401, was diametrically different; it tolerated Na+ at 200 millimolar, but K+ at the same concentration proved toxic to it. Short-term comparative studies on the absorption and translocation of Na+, K+, and Cl? of the two species were carried out using radioactive tracers with excised roots and whole plants. These studies showed that, under high salt conditions (50-100 millimolar NaCl), the tolerant 1401 freely accumulated Na+ in the shoot, while the salt-sensitive cultivar excluded it from the leaves, where it has been shown to be toxic. In experiments where K+ was limiting, the salt-tolerant species could partially substitute Na+ for K+. Sodium stimulated growth even when K+ was present at adequate concentrations. The domestic cultivar could not substitute Na+ for K+ and showed no similar growth stimulation when Na+ was added in the presence of adequate K+. The salt-tolerant 1401 was more efficient in K+ absorption than was the domestic cultivar at both low and moderate ambient K+ concentrations. The two species differed little in their chloride relations. Images

Rush, Dale W.; Epstein, Emanuel




Technology Transfer Automated Retrieval System (TEKTRAN)

The plant family Tamaricaceae contains 3-4 genera and some 80 species of shrubs and small trees, usually halophytic. They are native to Europe, Asia, and Africa, but species of Tamarix have become naturalized in Australia and the Americas. This treatment reviews the latest knowledge of vegetative mo...


Long-chain (C19-C29) 1-chloro-n-alkanes in leaf waxes of halophytes of the Chenopodiaceae.  


The hydrocarbon fraction of leaf waxes of three halophytes of the Chenopodiaceae common to Mediterranean salt marshes (Suaeda vera, Sarcocornia fruticosa and Halimione portulacoides) revealed the presence of a minor series of odd and even chains 1-chloro-n-alkanes ranging from C(19) to C(29). The identification of these new chlorinated plant constituents was based on a combination of mass spectrometry data with selective chlorine detection (CPG-AED) and was confirmed by comparison with authentic standards. The qualitative and quantitative distributions of these 1-chloro-n-alkanes varied inter-specifically. Homologues with an odd carbon-chain were predominant in all species but maximised at C(25) and C(27) in S. vera and S. fruticosa, and at C(27) and C(29) in H. portulacoides. Remarkably, 1-chloro-nonacosane was an abundant homologue only in this latter species. Leaves of S. vera contained 4 to 7 times more of total chloroalkanes than leaves of the other two species. These compounds accounted for 10, 4 and 1% of the hydrocarbon fraction of leaf waxes of S. vera, S. fruticosa and H. portulacoides, respectively. Attempts to link the occurrence of these chloroalkanes with other classes of leaf waxes (n-alkenes, n-aldehydes and n-alcohols) did not allowed a clear precursor-product relationship to be established. The biological functions as well as the mode of synthesis of alkylchlorides in (halophyte) plants remain unknown but undoubtedly deserve further attention. PMID:12842142

Grossi, Vincent; Raphel, Danielle



Seed germination of the halophyte Suaeda japonica under salt stress  

Microsoft Academic Search

Suaeda japonica Makino belonging to the family Chenopodiaceae, is a halophyte and grows at the shore of Ariake sea in Japan. This plant presumably\\u000a possesses high salt resistant nature, thus, we examined the mechanisms of seed germination under salt stress. The seeds maintained\\u000a 80% germination rates on the medium containing 0.7 M NaCl. Germination rates varied depending on salt type;

Takaharu Yokoishi; Shizufumi Tanimoto



Evidence for a Large and Sustained Glycolytic Flux to Lactate in Anoxic Roots of Some Members of the Halophytic Genus Limonium.  


Soil salinity and anaerobiosis often occur together. This led us to investigate the fermentative metabolism in roots of species from the halophytic genus Limonium (Plumbaginaceae). Root segments from hypoxically induced plants were incubated for 8 h under strict anoxia in the presence of [U-14C]glucose. In three species (Limonium latifolium, L. nashii, and L. humile), the pattern of 14C-labeled end products was typical of higher plants, with a 14C flux to ethanol higher than that to lactate. However, in four species (L. ramosissimum, L. gougetianum, L perezii, and L. sinuatum), the rate of lactate fermentation was exceptionally high, and in the latter two species the 14C flux to lactate exceeded that to ethanol. These two species secreted most of the lactate produced into the medium. Calculations indicated that the cytoplasm would have been lethally acidified had this secretion not occurred. The effects of factors that might control lactate fermentation or secretion (O2 partial pressure, pH, salt concentration) were studied in two contrasting species: L. sinuatum and L. latifolium. In both species, the lactate:ethanol ratio was higher under hypoxia (0.1-3 kPa O2 partial pressure) than under strict anoxia. In L. sinuatum, this ratio was slightly increased by increasing the pH of the medium from 5.5 to 7.5, but salinity treatment had no effect. The potential contribution of lactate fermentation to the overall carbon and energy metabolism of halophytes is discussed. PMID:12231709

Rivoal, J.; Hanson, A. D.



Evidence for a Large and Sustained Glycolytic Flux to Lactate in Anoxic Roots of Some Members of the Halophytic Genus Limonium.  

PubMed Central

Soil salinity and anaerobiosis often occur together. This led us to investigate the fermentative metabolism in roots of species from the halophytic genus Limonium (Plumbaginaceae). Root segments from hypoxically induced plants were incubated for 8 h under strict anoxia in the presence of [U-14C]glucose. In three species (Limonium latifolium, L. nashii, and L. humile), the pattern of 14C-labeled end products was typical of higher plants, with a 14C flux to ethanol higher than that to lactate. However, in four species (L. ramosissimum, L. gougetianum, L perezii, and L. sinuatum), the rate of lactate fermentation was exceptionally high, and in the latter two species the 14C flux to lactate exceeded that to ethanol. These two species secreted most of the lactate produced into the medium. Calculations indicated that the cytoplasm would have been lethally acidified had this secretion not occurred. The effects of factors that might control lactate fermentation or secretion (O2 partial pressure, pH, salt concentration) were studied in two contrasting species: L. sinuatum and L. latifolium. In both species, the lactate:ethanol ratio was higher under hypoxia (0.1-3 kPa O2 partial pressure) than under strict anoxia. In L. sinuatum, this ratio was slightly increased by increasing the pH of the medium from 5.5 to 7.5, but salinity treatment had no effect. The potential contribution of lactate fermentation to the overall carbon and energy metabolism of halophytes is discussed.

Rivoal, J.; Hanson, A. D.



Genome Structures and Halophyte-Specific Gene Expression of the Extremophile Thellungiella parvula in Comparison with Thellungiella salsuginea (Thellungiella halophila) and Arabidopsis1[W  

PubMed Central

The genome of Thellungiella parvula, a halophytic relative of Arabidopsis (Arabidopsis thaliana), is being assembled using Roche-454 sequencing. Analyses of a 10-Mb scaffold revealed synteny with Arabidopsis, with recombination and inversion and an uneven distribution of repeat sequences. T. parvula genome structure and DNA sequences were compared with orthologous regions from Arabidopsis and publicly available bacterial artificial chromosome sequences from Thellungiella salsuginea (previously Thellungiella halophila). The three-way comparison of sequences, from one abiotic stress-sensitive species and two tolerant species, revealed extensive sequence conservation and microcolinearity, but grouping Thellungiella species separately from Arabidopsis. However, the T. parvula segments are distinguished from their T. salsuginea counterparts by a pronounced paucity of repeat sequences, resulting in a 30% shorter DNA segment with essentially the same gene content in T. parvula. Among the genes is SALT OVERLY SENSITIVE1 (SOS1), a sodium/proton antiporter, which represents an essential component of plant salinity stress tolerance. Although the SOS1 coding region is highly conserved among all three species, the promoter regions show conservation only between the two Thellungiella species. Comparative transcript analyses revealed higher levels of basal as well as salt-induced SOS1 expression in both Thellungiella species as compared with Arabidopsis. The Thellungiella species and other halophytes share conserved pyrimidine-rich 5? untranslated region proximal regions of SOS1 that are missing in Arabidopsis. Completion of the genome structure of T. parvula is expected to highlight distinctive genetic elements underlying the extremophile lifestyle of this species.

Oh, Dong-Ha; Dassanayake, Maheshi; Haas, Jeffrey S.; Kropornika, Anna; Wright, Chris; d'Urzo, Matilde Paino; Hong, Hyewon; Ali, Shahjahan; Hernandez, Alvaro; Lambert, Georgina M.; Inan, Gunsu; Galbraith, David W.; Bressan, Ray A.; Yun, Dae-Jin; Zhu, Jian-Kang; Cheeseman, John M.; Bohnert, Hans J.



Predicting plant species' responses to grazing  

Microsoft Academic Search

Summary 1. The aim of this study was to identify whether plant species show consistent responses to livestock grazing. The analyses were based on 35 published studies from Australian rangelands providing 55 species response lists. The primary data set comprised 1554 responses from 829 species. 2. Eight-hundred and twenty-nine species were categorized as increasers, decreasers or neutral under grazing. Of




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



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




Microsoft Academic Search

Plant-soil relationship of saline coastal plain of north China was studied. Principle component analysis (PCA) and cluster analysis were used to generate a hypothesis that the distribution pattern of halophytic vegetation was influenced by the variation in soil properties. The hypothesis was tested by canonical correlation analysis (CCA). PCA results showed that salinity, pH, moisture and available nitrogen were the




The Occurrence of Mycorrhizas in Halophytes, Hydrophytes and Xerophytes, and of Endogone Spores in Adjacent Soils  

Microsoft Academic Search

SUMMARY The incidence of mycorrhizas in the roots and Endogone spores in rhizosphere soil of 52 xerophytes, 21 halophytes and 16 hydrophytes from Pakistan was investigated. Vesicular-arbuscular mycorrhizas were of general occurrence in all plants examined except hydrophytes and members of the families Urticaceae, Casuarinaceae, Nyctaginaceae, Portulaceae, Caryophyllaceae, Amaranthaceae, Chenopodiaceae, Capparaceae, Oleaceae, Elaeagnaceae, Zygophyllaceae, Tamari- caceae, Euphorbiaceae and Palmae. Mycorrhizas

A. G. Khan



Cadmium effects on growth and mineral nutrition of two halophytes: Sesuvium portulacastrum and Mesembryanthemum crystallinum.  


Growth, cadmium accumulation and potassium and calcium status were studied in two halophytes from Aizoaceae family: Sesuvium portulacastrum and Mesembryanthemum crystallinum. After multiplication, the seedlings were cultivated on nutrient solution supplemented with NaCl (100mM) and CdCl2 (0, 50, 100, 200 and 300 microM). After 1 month of treatment, plants were harvested and the dry weight, as well as the Cd, K and Ca concentrations in tissues were determined. Results showed that S. portulacastrum, a perennial halophyte with slow growth, is significantly more tolerant to Cd than M. crystallinum, an annual plant. Cd severely inhibited Mesembryanthemum growth even at the lowest Cd concentration in culture medium (50 microM), and did not modify significantly that of Sesuvium. For both halophytes, Cd accumulation was significantly higher in the roots than in the shoots. However, Cd concentration reached 350-700 microg g(-1) DM in the shoots, values characteristic of Cd hyperaccumulator plants. The addition of Cd in the culture medium led to a disturbance of Ca and especially K nutrition, suggesting the possibility to improve plant growth and Cd phytoextraction of both halophytes by increasing nutrient availability in the culture medium. PMID:16255171

Ghnaya, Tahar; Nouairi, Issam; Slama, Inès; Messedi, Dorsaf; Grignon, Claude; Abdelly, Chedly; Ghorbel, Mohamed Habib



Investigation of Vegetation Species in Desert Areas of Fars Province  

NASA Astrophysics Data System (ADS)

The Fars province is located in the south of IRAN, with area of 122830Km2. This areas involved saline and alkaline soils. The aim of this research is investigation of salty lands and vegetation degradation for offering of sociable species for any area. Recognition studying of desert area in Fars province was identified using all available data and using GIS and RS technologies. In this study, main indicators have been appointed using Floristical-Fizionomicaly method. Vegetation per cent, growth form, density and altitude were considered as main indicators. More than 50 species of halophytes were collected and 25 plant types were identified in 17 zones of studied area. The main plant types were as follows: Hammada, Halocnemum-Aeluropus and Halocnemum-limonium. Ultimately, halophytes cover map was prepared. In the end of growth season, 50 soil samples from halophyte types in two horizons 0-30cm and 30-100cm were taken and tested. The result showed, the studied area, has saline lands surface and high salinity land with cover of 9000Km2. Keyword: Saline Soil, Alkaline Soil, Halophytes, Fars Province

Fozoni, L.; Fakhireh, A.



Comparative Physiological Evidence that beta-Alanine Betaine and Choline-O-Sulfate Act as Compatible Osmolytes in Halophytic Limonium Species.  


The quaternary ammonium compounds accumulated in saline conditions by five salt-tolerant species of Limonium (Plumbaginaceae) were analyzed by fast atom bombardment mass spectrometry. Three species accumulated beta-alanine betaine and choline-O-sulfate; the others accumulated glycine betaine and choline-O-sulfate. Three lines of evidence indicated that beta-alanine betaine and choline-O-sulfate replace glycine betaine as osmo-regulatory solutes. First, tests with bacteria showed that beta-alanine betaine and choline-O-sulfate have osmoprotective properties comparable to glycine betaine. Second, when beta-alanine betaine and glycine betaine accumulators were salinized, the levels of their respective betaines, plus that of choline-O-sulfate, were closely correlated with leaf solute potential. Third, substitution of sulfate for chloride salinity caused an increase in the level of choline-O-sulfate and a matching decrease in glycine betaine level. Experiments with (14)C-labeled precursors established that beta-alanine betaine accumulators did not synthesize glycine betaine and vice versa. These experiments also showed that beta-alanine betaine synthesis occurs in roots as well as leaves of beta-alanine betaine accumulators and that choline-O-sulfate and glycine betaine share choline as a precursor. Unlike glycine betaine, beta-alanine betaine synthesis cannot interfere with conjugation of sulfate to choline by competing for choline and does not require oxygen. These features of beta-alanine betaine may be advantageous in sulfate-rich salt marsh environments. PMID:16668509

Hanson, A D; Rathinasabapathi, B; Chamberlin, B; Gage, D A




Technology Transfer Automated Retrieval System (TEKTRAN)

The allelopathic effects of Artemisia annua, A. californica, A. princeps var. orientalis, A. tridentata, and A. vulgaris are reviewed. Naturally produced allelopathic compounds that reach target species via natural methods of dissemination (air, soil, and rain) are emphasized. Possible modes of ac...


Comparative chlorine requirements of different plant species  

Microsoft Academic Search

Summary Recognition of chlorine as a plant micronutrient has been extended to include ten species. Acute chlorine deficiencies or decreased yields were produced with lettuce, tomato, cabbage, carrot, sugar beet, barley, alfalfa, buckwheat, corn, and beans. Squash plants showed neither loss in yield nor other deficiency symptoms when cultured at the same time and under the same conditions as the

C. M. Johnson; P. R. Stout; T. C. Broyer; A. B. Carlton



River confluences enhance riparian plant species diversity  

Microsoft Academic Search

In riparian zones along the banks of streams and rivers, flooding often causes large changes in environmental conditions immediately\\u000a downstream of confluences. In turn, spatial heterogeneity in flooding along rivers and streams likely affects local species\\u000a diversity. Furthermore, flooding during the plant growing season can strongly affect plant survival. In this study, we hypothesized\\u000a that confluences have impacts on plant

Takeshi Osawa; Hiromune Mitsuhashi; Atushi Ushimaru



Stimulation of photosynthetic electron transport in a salt-tolerant plant by high chloride concentrations  

Microsoft Academic Search

Halophytes are plants which tolerate high concentrations of electrolytes of which NaCl is normally the dominating salt. Compartmentation of the electrolytes within the cytoplasm has not been unequivocally resolved1. Several soluble enzymes from higher plant halophytes showed similar sensitivity to salinity when tested in vitro as did those from glycophytes2. Also, isolated mitochondria from halophytes and glycophytes showed similar inhibition

Christa Critchley



Species interaction mechanisms maintain grassland plant species diversity  

Technology Transfer Automated Retrieval System (TEKTRAN)

Theory has outpaced empirical research in pursuit of identifying mechanisms maintaining species diversity. Here we demonstrate how data from diversity-ecosystem functioning experiments can be used to test maintenance of diversity theory. We predict that grassland plant diversity can be maintained by...


Biodiversity hotspots house most undiscovered plant species  

PubMed Central

For most organisms, the number of described species considerably underestimates how many exist. This is itself a problem and causes secondary complications given present high rates of species extinction. Known numbers of flowering plants form the basis of biodiversity “hotspots”—places where high levels of endemism and habitat loss coincide to produce high extinction rates. How different would conservation priorities be if the catalog were complete? Approximately 15% more species of flowering plant are likely still undiscovered. They are almost certainly rare, and depending on where they live, suffer high risks of extinction from habitat loss and global climate disruption. By using a model that incorporates taxonomic effort over time, regions predicted to contain large numbers of undiscovered species are already conservation priorities. Our results leave global conservation priorities more or less intact, but suggest considerably higher levels of species imperilment than previously acknowledged.

Joppa, Lucas N.; Roberts, David L.; Myers, Norman; Pimm, Stuart L.



Applying the species concept to plant viruses.  


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. The rationale for applying the species concept in virology is that viruses are biological entities and not chemicals: they possess genes, replicate, specialize, evolve and occupy specific ecological niches. The following definition is proposed: a virus species is a polythetic class of viruses constituting a replicating lineage and occupying a particular ecological niche. Such a definition of the species category does not and cannot provide a list of diagnostic properties for recognizing members of a particular virus species. It should also be stressed that a single property such as an arbitrary level of genome homology or the extent of serological relationship always fails to establish membership in a polythetic class. A binomial system of nomenclature is advocated in which the vernacular English name of the plant virus is adopted as the species name and the group name is assimilated to the level of genus. Adoption of this system would ensure that a universal classification system based on the classical categories of species, genus, and family becomes possible for all viruses. PMID:2647059

Van Regenmortel, M H



The species problem in plant virology.  


The systems currently used to classify and name viruses are discussed. It is concluded that, while the family-genus-species system is widely used for many viruses, the virus group-virus system used for plant viruses has a sounder theoretical basis and is easier to use. Its universal adoption should be considered. For plant viruses, the English vernacular name and the group name could form the basis of a binomial nomenclature. PMID:6444112

Milne, R G



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


Shifts in carbon isotope ratios of two C 3 halophytes under natural and artificial conditions  

Microsoft Academic Search

The total carbon d13C values of two C3 halophytes,Salicornia europaea L. ssp.rubra (Nels.) Breitung andPuccinellia muttalliana (Schultes) Hitch., native to inland saline areas of Alberta, Canada, were determined for plants grown under controlled conditions of supplied NaCl in the nutrient solution, and for plants found growing in the field. Field specimens were collected along line transects which ran from areas

Robert D. Guy; David M. Reid; H. Roy Krouse



Identification and sequencing of ESTs from the halophyte grass Aeluropus littoralis  

Microsoft Academic Search

Aeluropus littoralis (Gouan) Parl. is a C4 perennial halophyte monocotyledonous plant belonging to the same family of wheat. Growing as weed in dry salty areas or marshes, it is a salt-secreting, rhizomatous and is used as forage. It is diploid (2n=2X=14) and has a relative small genome of around 342 Mb. A. littoralis is highly salt-tolerant since this plant has the

Nabil Zouari; Rania Ben Saad; Thierry Legavre; Jalel Azaza; Xavier Sabau; Mohamed Jaoua; Khaled Masmoudi; Afif Hassairi



On the Local Coexistence of Species in Plant Communities  

Microsoft Academic Search

Coexistence of many competitive species is very common in natural plant communities. For example, almost all forests and grasslands consist of various species. Extremely high biodiversity is seen in tropical rain forests. Grassland communities also o ften consist of many species. In plant communities, spatially competitive species of plants coexist in a mosaic pattern. Communities with a single species are

J. Yoshimura; K. Tainaka; T. Suzuki; M. Shiyomi


Heterogeneous distribution of metabolites across plant species  

NASA Astrophysics Data System (ADS)

We investigate the distribution of flavonoids, a major category of plant secondary metabolites, across species. Flavonoids are known to show high species specificity, and were once considered as chemical markers for understanding adaptive evolution and characterization of living organisms. We investigate the distribution among species using bipartite networks, and find that two heterogeneous distributions are conserved among several families: the power-law distributions of the number of flavonoids in a species and the number of shared species of a particular flavonoid. In order to explain the possible origin of the heterogeneity, we propose a simple model with, essentially, a single parameter. As a result, we show that two respective power-law statistics emerge from simple evolutionary mechanisms based on a multiplicative process. These findings provide insights into the evolution of metabolite diversity and characterization of living organisms that defy genome sequence analysis for different reasons.

Takemoto, Kazuhiro; Arita, Masanori



Cellular Responses To Salinity Of Two Coastal Halophytes With Different Whole Plant Tolerance: Kosteletzkya Virginica (L.) Presl. And Sporobolus Virginicus (L.) Kunth  

Microsoft Academic Search

At the whole plant level, Sporobolus virginicus is more salt-tolerant than Kosteletzkya virginica. Cellular level (callus and protoplast) responses to salinity are reported here. The callus of Kosteletzkya had higher relative growth rates than Sporobolus, particularly at the highest salinity, however survival rate at 170 and 340 mM NaC1 was similar. Upon salinization, Kosteletzkya had higher cell wall digestibility and

Xianggan Li; Denise M. Seliskar; John L. Gallagher


Plant species evaluated for new crop potential  

SciTech Connect

Ninety-two plant species from various regions of the USA were screened for their energy-producing potential. Samples were analysed for oil, polyphenol, hydrocarbon and protein. Oil fractions of some species were analysed for classes of lipid constituents and yields of unsaponifiable matter and fatty acids were determined. Hydrocarbon fractions of some species were analysed for rubber, gutta and waxes. Average MW and MW distribution of rubber and gutta were determined. Complete analytical data for 16 species is presented. Large quantities of oil were obtained from Philadelphus coronarius, Cacalia muhlenbergii, Lindera benzoin and Koelreuteria paniculata. High yields of polyphenols came from Acer ginnala, Cornus obliqua and Salix caprea and maximum yields of hydrocarbon and protein were from Elymus virginicus and Lindera benzoin, respectively.

Carr, M.E.



Species-specific positive effects in an annual plant community  

Microsoft Academic Search

Plant facilitation studies commonly test the nurse-plant hypothesis wherein an adult shrub species enhances the establishment of associated herbaceous species under its canopy. Using field and glasshouse experiments, this hypothesis is extended by testing the following four predictions: (1) nurse-plant effects can occur between species with similar life- forms and phenologies (2) positive effects are species specific, (3) the outcome

Christopher J. Lortie; Roy Turkington



The mericarp of the halophyte Crithmum maritimum (Apiaceae): structural features, germination, and salt distribution  

Microsoft Academic Search

At maturation and during seed fall and dispersal, halophyte seeds may be subjected to invasion by salt ions. How these seeds\\u000a remain viable in such hostile environments is however still unclear, depending for instance on the species and the family.\\u000a In the Apiaceae, the mericarp (fruit) shows a wide range of morphological and anatomical modifications, many of which may\\u000a enhance

Abdallah Atia; Ahmed Debez; Zouhaier Barhoumi; Ettore Pacini; Chedly Abdelly; Abderrazak Smaoui



Effect of Soil Microbiomass and Microbial PLFA on Different Halophyte Communities in the Yellow River Delta  

Microsoft Academic Search

This study focused on the relationship between four halophyte communities(Phragmites australis ,Tamarix chinensis ,Suaeda salsa,Aeluropus sinensis) and soil parament and soil microbial in the Yellow River Delta. Effects of plant communities on soil parament and soil micro-biomass and soil microbial community compositions were assessed using soil chemical? chloroform fumigation extraction and Phospholipid fatty acid methods ,respectively. Phospholipid fatty acid (PLFA)

Di Cao; Fuchen Shi; Zhaohua Lu; Zhigang Yao; Jingtao Liu; Hongjun Yang



Physiological and antioxidant responses of the perennial halophyte Crithmum maritimum to salinity  

Microsoft Academic Search

Physiological behavior and antioxidant responses to salinity were studied in Crithmum maritimum, a local halophyte naturally growing on rocky coasts. The plant growth was significantly improved at moderate salt levels (50mM NaCl), but was drastically reduced at 200mM NaCl. The stimulation of biomass production at 50mM NaCl was associated with enhanced root length and leaf number. Tissue hydration seemed unaffected

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



Sesuvium portulacastrum (L.) L. a promising halophyte: cultivation, utilization and distribution in India  

Microsoft Academic Search

Seapurslane, Sesuvium portulacastrum (L.) L. (Aizoaceae) is a pioneer, psammophytic facultative halophyte naturally growing in the subtropical, mediterranean,\\u000a coastal and warmer zones of the world. The plant is utilized as a vegetable by the local peoples as well as forage for domestic\\u000a animals in the coastal area. Environmentally, it is utilized for the bioreclamation of saline soil in the arid

Vinayak Haribhau Lokhande; Tukaram Dayaram Nikam; Penna Suprasanna




EPA Science Inventory

Understanding hydrologic requirements of native and introduced species is critical to sustaining native plant communities in wetlands of disturbed landscapes. We examined plant assemblages and 31 species from emergent wetlands in an urbanizing area of the Pacific Northwest, USA, ...



EPA Science Inventory

Understanding hydrologic requirements of native and introduced species is critical to sustaining native plant communities in wetlands of disturbed landscapes. We examined plant assemblages and 31 species from emergent wetlands in an urbanizing area of the Pacific Northwest, USA,...


Effects of Cd2+ on K+, Ca2+ and N uptake in two halophytes Sesuvium portulacastrum and Mesembryanthemum crystallinum: consequences on growth.  


One of the limits of Cd2+-phytoextraction is the high toxicity of this metal to plants. Growth restriction, chlorosis and necrosis are usually accompanied with a large disturbance of the uptake of essential elements. This work aims to study the effects of cadmium (Cd2+) on potassium (K+), calcium (Ca2+) and nitrogen (N) acquisition, and their consequences on growth in two halophytes species: Sesuvium portulacastrum and Mesembryanthemum crystallinum. Seedlings were grown for 30 days in split-root conditions. One half of the root system was immersed in complete nutrient solution (Basal medium (B)) supplemented with 100 microM Cd2+, and the other half was immersed in a Cd2+-free medium, containing all nutrients (B/Cd plants) or deprived of potassium ((B-K)/Cd) or calcium ((B-Ca)/Cd) or nitrogen ((B-N)/Cd). Using this approach, we demonstrated that K+ and Ca2+ uptake was impaired in roots exposed to Cd2+. Concerning N, we noticed no indication of uptake inhibition by Cd2+. However, restriction of K+ uptake by roots was compensated by an increase in the K+-use efficiency, so that growth was not inhibited. Calcium uptake was strongly limited by Cd2. This inhibition was accompanied by a reduction in growth of ((B-Ca)/Cd) plants. Thus, we conclude that Cd2+ limits growth of both halophytes through restriction imposed on Ca2+ uptake. We suggest that the increase of Ca2+ availability in soils could improve the growth of both species in the presence of Cd2+. This would be essential for improving their utility for extraction of this metal by from salty contaminated soils. PMID:17126878

Ghnaya, Tahar; Slama, Inès; Messedi, Dorsaf; Grignon, Claude; Ghorbel, Mohamed Habib; Abdelly, Chedly



Functional identity versus species richness: herbivory resistance in plant communities  

Microsoft Academic Search

The resistance of a plant community against herbivore attack may depend on plant species richness, with monocultures often much more severely affected than mixtures of plant species. Here, we used a plant-herbivore system to study the effects of selective herbivory on consumption resistance and recovery after herbivory in 81 experimental grassland plots. Communities were established from seed in 2002 and

Christoph Scherber; Juliane Heimann; Guenter Koeler; Nadine Mitschunas; Wolfgang W. Weisser



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.


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.


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


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



Interactive effects of salt and alkali stresses on seed germination, germination recovery, and seedling growth of a halophyte Spartina alterniflora (Poaceae)  

Microsoft Academic Search

Soil salinization and alkalinization frequently co-occur in nature, but there is little information on the interactive effects of salt and alkali stresses on plants. Seed germination and early seedling growth are crucial stages for plant establishment. We investigated the interactive effects of salt and alkali stresses on seed germination, germination recovery and seedling growth of a halophyte Spartina alterniflora. Seed

R. Li; F. Shi; K. Fukuda



Kineococcus endophytica sp. nov., a novel endophytic actinomycete isolated from a coastal halophyte in Jiangsu, China.  


A novel Gram-positive, motile, non-spore-forming coccus-shaped bacterial strain, designated KLBMP 1274(T), was isolated from a halophytic plant (Limonium sinense) collected from the coastal region of Nantong, Jiangsu Province, in east China. Phylogenetic analyses based on the 16S rRNA gene sequence showed that strain KLBMP 1274(T) belongs to the genus Kineococcus and is closely related to Kineococcus rhizosphaerae RP-B16(T) (98.72 %), Kineococcus aurantiacus IFO 15268(T) (98.71 %), Kineococcus radiotolerans SRS30216(T) (98.69 %) and Kineococcus gynurae KKD096(T) (97.33 %). The 16S rRNA gene sequence similarity to other species of the genus Kineococcus was <97 %. The cell wall contained meso-diaminopimelic acid as the diagnostic diamino acid, with arabinose and galactose as the characteristic sugars. The predominant menaquinone was MK-9(H(2)). The polar lipids were found to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides, an unknown phospholipid, an unknown glycolipid, and three unknown lipids. Major cellular fatty acids were found to be anteiso-C(15: 0) and iso-C(14: 0). The chemotaxonomic data for strain KLBMP 1274(T) were typical of the genus Kineococcus. The total DNA G+C content was 73.4 mol %. DNA-DNA relatedness and differential phenotypic data demonstrated that strain KLBMP 1274(T) was clearly distinguished from all closely related species of the genus Kineococcus. Thus, strain KLBMP 1274(T) represents a novel species of the genus Kineococcus, for which the name Kineococcus endophytica sp. nov. is proposed. The type strain is KLBMP 1274(T) (=KCTC 19886 (T) = NBRC 108674(T)). PMID:22669199

Bian, Guang-Kai; Feng, Zhao-Zhong; Qin, Sheng; Xing, Ke; Wang, Zhe; Cao, Cheng-Liang; Liu, Chang-Hong; Dai, Chuan-Chao; Jiang, Ji-Hong



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)



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



Expressed sequence tags from the halophyte Limonium sinense.  


Halophytes can grow under a high salinity condition. Similar to glycophytes, their salt-tolerance possesses a high genetic complexity. There are many morphological and physiological studies on halophytes but very little information is at molecular level why they are salt-tolerant. Limonium sinense is a salt-secreting halophyte and can excretes salts by multi-cellular glands. Here, we report the library construction and sequence analysis of a cDNA library made from leaf tissue of L. sinenes. Among those 1082 expressed sequence tag (EST) obtained, 684 unique genes were identified: 429 showed homology to previously identified genes, 255 matched to uncharacterized genes. Compared with other EST databases, some characteristic features such as abundance genes in related to cytoskeleton and intracellular traffic, membrane transporting were observed, which may be specific to halophytes. PMID:17364815

Chen, Shi-Hua; Guo, Shan Li; Wang, Zeng Lan; Zhao, Ji Qiang; Zhao, Yan Xiu; Zhang, Hui



Halophyte filter beds for treatment of saline wastewater from aquaculture.  


The expansion of aquaculture and the recent development of more intensive land-based marine farms require efficient and cost-effective systems for treatment of highly nutrient-rich saline wastewater. Constructed wetlands with halophytic plants offer the potential for waste-stream treatment combined with production of valuable secondary plant crops. Pilot wetland filter beds, constructed in triplicate and planted with the saltmarsh plant Salicornia europaea, were evaluated over 88 days under commercial operating conditions on a marine fish and shrimp farm. Nitrogen waste was primarily in the form of dissolved inorganic nitrogen (TDIN) and was removed by 98.2 ± 2.2% under ambient loadings of 109-383 ?mol l(-1). There was a linear relationship between TDIN uptake and loading over the range of inputs tested. At peak loadings of up to 8185 ± 590 ?mol l(-1) (equivalent to 600 mmol N m(-2) d(-1)), the filter beds removed between 30 and 58% (250 mmol N m(-2) d(-1)) of influent TDIN. Influent dissolved inorganic phosphorus levels ranged from 34 to 90 ?mol l(-1), with 36-89% reduction under routine operations. Dissolved organic nitrogen (DON) loadings were lower (11-144 ?mol l(-1)), and between 23 and 69% of influent DON was removed during routine operation, with no significant removal of DON under high TDIN loading. Over the 88-day study, cumulative nitrogen removal was 1.28 mol m(-2), of which 1.09 mol m(-2) was retained in plant tissue, with plant uptake ranging from 2.4 to 27.0 mmol N g(-1) dry weight d(-1). The results demonstrate the effectiveness of N and P removal from wastewater from land-based intensive marine aquaculture farms by constructed wetlands planted with S. europaea. PMID:22818948

Webb, J M; Quintã, R; Papadimitriou, S; Norman, L; Rigby, M; Thomas, D N; Le Vay, L



Soil organisms shape the competition between grassland plant species.  


Decomposers and arbuscular mycorrhizal fungi (AMF) both determine plant nutrition; however, little is known about their interactive effects on plant communities. We set up a greenhouse experiment to study effects of plant competition (one- and two-species treatments), Collembola (Heteromurus nitidus and Protaphorura armata), and AMF (Glomus intraradices) on the performance (above- and belowground productivity and nutrient uptake) of three grassland plant species (Lolium perenne, Trifolium pratense, and Plantago lanceolata) belonging to three dominant plant functional groups (grasses, legumes, and herbs). Generally, L. perenne benefited from being released from intraspecific competition in the presence of T. pratense and P. lanceolata. However, the presence of AMF increased the competitive strength of P. lanceolata and T. pratense against L. perenne and also modified the effects of Collembola on plant productivity. The colonization of roots by AMF was reduced in treatments with two plant species suggesting that plant infection by AMF was modified by interspecific plant interactions. Collembola did not affect total colonization of roots by AMF, but increased the number of mycorrhizal vesicles in P. lanceolata. AMF and Collembola both enhanced the amount of N and P in plant shoot tissue, but impacts of Collembola were less pronounced in the presence of AMF. Overall, the results suggest that, by differentially affecting the nutrient acquisition and performance of plant species, AMF and Collembola interactively modify plant competition and shape the composition of grassland plant communities. The results suggest that mechanisms shaping plant community composition can only be understood when complex belowground interactions are considered. PMID:22678109

Sabais, Alexander C W; Eisenhauer, Nico; König, Stephan; Renker, Carsten; Buscot, François; Scheu, Stefan



Gas chromatographic-mass spectrometric method for polycyclic aromatic hydrocarbon analysis in plant biota.  


Using gas chromatography-mass spectrometry, a new method was developed for the identification and the quantification of polycyclic aromatic hydrocarbons (PAHs) in plants. This method was particularly optimised for PAH analyses in marine plants such as the halophytic species, Salicornia fragilis Ball et Tutin. The saponification of samples and their clean up by Florisil solid-phase extraction succeeded in eliminating pigments and natural compounds, which may interfere with GC-MS analysis. Moreover, a good recovery of the PAHs studied was obtained with percentages ranging from 88 to 116%. Application to the determination of PAH in a wide range of coastal halophytic plants is presented and validated the efficiency, the accuracy and the reproducibility of this method. PMID:16442550

Meudec, A; Dussauze, J; Jourdin, M; Deslandes, E; Poupart, N



??????????????????????????????????????????????? Tissue culture of Rare and Endemic Plant Species)  

Microsoft Academic Search

Tissue culture technique can be used to conserve rare or endangered plant species. It quickly produces large number of new plants by placing explants on the surface of solid culture medium. In this study, four media, i.e. Knudson, Murashige and Skoog, Vacin and Went, and OD formula, were identified, that can grow rare and endangered species of orchids. The results


Host plant species affects virulence in monarch butterfly parasites.  


1. Studies have considered how intrinsic host and parasite properties determine parasite virulence, but have largely ignored the role of extrinsic ecological factors in its expression. 2. We studied how parasite genotype and host plant species interact to determine virulence of the protozoan parasite Ophryocystis elektroscirrha (McLaughlin & Myers 1970) in the monarch butterfly Danaus plexippus L. We infected monarch larvae with one of four parasite genotypes and reared them on two milkweed species that differed in their levels of cardenolides: toxic chemicals involved in predator defence. 3. Parasite infection, replication and virulence were affected strongly by host plant species. While uninfected monarchs lived equally long on both plant species, infected monarchs suffered a greater reduction in their life spans (55% vs. 30%) on the low-cardenolide vs. the high-cardenolide host plant. These life span differences resulted from different levels of parasite replication in monarchs reared on the two plant species. 4. The virulence rank order of parasite genotypes was unaffected by host plant species, suggesting that host plant species affected parasite genotypes similarly, rather than through complex plant species-parasite genotype interactions. 5. Our results demonstrate that host ecology importantly affects parasite virulence, with implications for host-parasite dynamics in natural populations. PMID:18177332

de Roode, Jacobus C; Pedersen, Amy B; Hunter, Mark D; Altizer, Sonia



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



Mechanisms of plant species impacts on ecosystem nitrogen cycling  

Microsoft Academic Search

Plant species are hypothesized to impact ecosystem nitrogen cycling in two distinctly different ways. First, differences in nitrogen use efficiency can lead to positive feedbacks on the rate of nitrogen cycling. Alternatively, plant species can also control the inputs and losses of nitrogen from ecosystems. Our current understanding of litter decomposition shows that most nitrogen present within litter is not

J. M. H. Knops; K. L. Bradley; D. A. Wedin




Technology Transfer Automated Retrieval System (TEKTRAN)

Invasive exotic plant species present a serious problem to natural resource managers in the United States. This paper presents an overview on the application of aerial photography and airborne videography for detecting invasive plant species in terrestrial and aquatic environments in the United Sta...


Leaf–water relations and ion concentrations of the halophyte Atriplex hortensis in response to salinity and water stress  

Microsoft Academic Search

The impact of salinity and water stress was analyzed in the xero-halophyte Atriplex hortensis using two varieties: green orach (A. hortensis var. purpurea) and red orach (A. hortensis var. rubra). A. hortensis L. is a C3 species well adapted to salt and drought conditions. To collect information on the physiological impact of different salt\\u000a and water deficit levels on their

S. Sai Kachout; A. Ben Mansoura; K. Jaffel Hamza; J. C. Leclerc; M. N. Rejeb; Z. Ouerghi



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


Sodium Stress in the Halophyte Thellungiella halophila and Transcriptional Changes in a thsos1 RNA Interference Line  

Microsoft Academic Search

The plasma membrane Na+\\/H+-antiporter salt overly sensitive1 (SOS1) from the halophytic Arabidopsis-relative Thel- lungiella halophila (ThSOS1) shows conserved sequence and domain structure with the orthologous genes from Arabidopsis thaliana and other plants. When expression of ThSOS1 was reduced by RNA interference (RNAi), pronounced characteristics of salt-sensitivity were observed. We were interested in monitoring altered transcriptional responses between Thellungiella wild type

Dong-Ha Oh; Qingqiu Gong; Alex Ulanov; Quan Zhang; Youzhi Li; Wenying Ma; Dae-Jin Yun; Ray A. Bressan; Hans J. Bohnert



Hydraulic lift among native plant species in the Mojave Desert  

Microsoft Academic Search

Hydraulic lift was investigated among native plants in the Mojave Desert using in situ thermocouple psychrometers. Night lighting and day shading experiments were used to verify the phenomenon. Hydraulic lift was detected for all species examined: five shrub species with different rooting depths and leaf phenologies and one perennial grass species. This study was the first to document hydraulic lift

Carolyn K. Yoder; Robert S. Nowak



Investigating habitat-specific plant species pools under climate change  

Microsoft Academic Search

We used 474 European plant species to analyse the impacts of climate and land-use change on the composition of habitat-specific species pools in Germany. We quantified changes in the probability of occurrence of species in a grid cell using an ensemble of three statistical modelling techniques, namely generalized linear models (GLMs), generalized additive models (GAMs) and random forests (RFs), under

Sven Pompe; Jan Hanspach; Franz-W. Badeck; Stefan Klotz; Helge Bruelheide; Ingolf Kühn



Cation-anion relationships in a nonfacultative halophyte, Galenia pubescens  

SciTech Connect

Galenia pubescens (Eckl. and Zeyh) Druce was grown in solution culture under a variety of conditions to test its cation-anion relationships. It is a plant in which mineral cations exceed mineral anions. It then has from fewer than 100 to 400 or more milliequivalents per 100 grams of organic acid anions to balance cations minus anions. Mineral cations exceeded mineral anions in leaves, stems, and roots whether sodium chloride as added in abundance or whether the nitrogen source was nitrate, ammonia, or urea. When sodium or chlorine was added, both ions tended to accumulate in leaves rather than in roots; sodium was more pronounced in this respect than was chlorine. Galenia pubescens grew as well in a solution or in soil containing 400 meq/liter NaCl as in one without NaCl. The 400 meq/liter Na/sub 2/SO/sub 4/ was excessive. Galenia pubescens is a subtropical nonfacultative halophyte that can grow in nonsaline conditions and also in seawater. It has a very high rate of photosynthesis and capacity to synthesize large quantities of protein. It has possibilities as a biomass crop.

Wallace, A.



Interaction between plant agglutinins and Legionella species.  

PubMed Central

Serogroups of Legionella pneumophila exhibited differential reactivities with plant agglutinin. Agglutination patterns were modified by growing the organisms in different media. The passage of four strains through guinea pigs did not result in altered reactivities with lectins or with plant agglutinins.

Doyle, R J; Nedjat-Haiem, F; Miller, R D; Keller, K F



Interaction between plant agglutinins and Legionella species.  


Serogroups of Legionella pneumophila exhibited differential reactivities with plant agglutinin. Agglutination patterns were modified by growing the organisms in different media. The passage of four strains through guinea pigs did not result in altered reactivities with lectins or with plant agglutinins. PMID:6808023

Doyle, R J; Nedjat-Haiem, F; Miller, R D; Keller, K F



Expression of the cation transporter McHKT1 in a halophyte.  


From the ice plant, Mesembryanthemum crystallinum, McHKT1 was isolated encoding a protein 41-61% identical to other plant HKT1-like sequences previously described as potassium or sodium/potassium transporters. McHKT1 acts as a potassium transporter in yeast with specificity similar to that of wheat HKT1. In Xenopus oocytes it transports cations with a specificity Rb+ > Cs+ > [K+ = Na+ = Li+]. McHKT1 is exclusively localized to the plasma membrane. The isoform isolated is most highly expressed in leaves and is present in stems, flowers and seed pods but absent from the root where, according to immunological data, a second isoform exists which does not cross-hybridize with the leaf form in RNA blots at high stringency. McHKT1 transcript amounts increase during the first 6-10 h of stress and then decline to pre-stress levels with kinetics reminiscent of the initial influx of sodium into this halophyte. Immunocytological localization showed strong signals in the leaf vasculature and surrounding mesophyll cells but low-intensity signals are also detected in other cell types. In roots, McHKT is mainly confined to endodermis and stele. Possible functions of McHKT1 in ion homeostasis in the halophytic ice plant are discussed. PMID:14558658

Su, Hua; Balderas, Enrique; Vera-Estrella, Rosario; Golldack, Dortje; Quigley, Francoise; Zhao, Chengsong; Pantoja, Omar; Bohnert, Hans J



Plant species persistence and turnover on small Bahamian islands.  


I conducted surveys of the plant species occupying 136 small islands in the Exuma Cays and 58 small islands near Andros, Bahamas. Most species occurred on relatively few islands, and most islands contained relatively few species. Identities of the most common species differed between the two archipelagos. Comparisons with earlier surveys revealed species extinctions and immigrations. Turnover was relatively low on both a per island and a per species basis on both archipelagos, although significant spatial variation in turnover rates between archipelagos was found. Most islands experienced no turnover; islands on which turnover did occur were larger and had higher species richness. Likewise, most species did not turnover, although much variation existed in turnover rates among those that did. Experimental introductions of two species to very small islands naturally devoid of vegetation revealed that these islands could support plant life. One species survived on eight of ten islands for >9 years, including the effects of a moderate (class 2) hurricane. This hurricane caused substantial damage and loss of plant biomass, but resulted in no species extinctions on 30 small islands. Data for the small islands in this region, now spanning almost a decade, reveal that most populations are persistent over periods of years to decades, rarely going extinct or immigrating. Even moderate hurricanes seem to have little impact on species compositions. PMID:12695903

Morrison, Lloyd W




Technology Transfer Automated Retrieval System (TEKTRAN)

Species abundances usually are not rigorously controlled when testing relationships between plant production and species richness and may be highly dynamic in disturbed or early successional communities. Whether species abundances affect the yield of mixtures relative to the yield expected from spe...



Technology Transfer Automated Retrieval System (TEKTRAN)

The distribution of genetic variants in plant populations is stronglyaffected by both current patterns of microevolutionary forces, such as geneflow or selection, and by the phylogenetic history of populations andspecies. Understanding the interplay of shared history and currentevolutionary events ...


Site and plant species are important determinants of the Methylobacterium community composition in the plant phyllosphere.  


The plant phyllosphere constitutes a habitat for numerous microorganisms; among them are members of the genus Methylobacterium. Owing to the ubiquitous occurrence of methylobacteria on plant leaves, they represent a suitable target for studying plant colonization patterns. The influence of the factor site, host plant species, time and the presence of other phyllosphere bacteria on Methylobacterium community composition and population size were evaluated in this study. Leaf samples were collected from Arabidopsis thaliana or Medicago truncatula plants and from the surrounding plant species at several sites. The abundance of cultivable Methylobacterium clearly correlated with the abundance of other phyllosphere bacteria, suggesting that methylobacteria constitute a considerable and rather stable fraction of the phyllosphere microbiota under varying environmental conditions. Automated ribosomal intergenic spacer analysis (ARISA) was applied to characterize the Methylobacterium community composition and showed the presence of similar communities on A. thaliana plants at most sites in 2 consecutive years of sampling. A substantial part of the observed variation in the community composition was explained by site and plant species, especially in the case of the plants collected at the Arabidopsis sites (50%). The dominating ARISA peaks that were detected on A. thaliana plants were found on other plant species grown at the same site, whereas some different peaks were detected on A. thaliana plants from other sites. This indicates that site-specific factors had a stronger impact on the Methylobacterium community composition than did plant-specific factors and that the Methylobacterium-plant association is not highly host plant species specific. PMID:20164863

Knief, Claudia; Ramette, Alban; Frances, Lisa; Alonso-Blanco, Carlos; Vorholt, Julia A



Exotic plants increase and native plants decrease with loss of foundation species in sagebrush steppe  

Microsoft Academic Search

Dominant plant species, or foundation species, are recognized to have a disproportionate control over resources in ecosystems,\\u000a but few studies have evaluated their relationship to exotic invasions. Loss of foundation species could increase resource\\u000a availability to the benefit of exotic plants, and could thereby facilitate invasion. The success of exotic plant invasions\\u000a in sagebrush steppe was hypothesized to benefit from

Janet S. Prevéy; Matthew J. Germino; Nancy J. Huntly; Richard S. Inouye



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

NASA Astrophysics Data System (ADS)

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 the bulk soil microbial community and selected soil processes. Plant species were associated with distinct ecosystem process rates such as net nitrogen mineralization, nitrification, decomposition and soil respiration. Bacterial community substrate utilization profiles differed among different plant species and were related to labile soil C. DNA-based fingerprints of bacterial, ammonia oxidizer, and fungal communities did not generally differ in soils planted to different species; however, these microbial community profiles did strongly correlate to rates of decomposition. Terminal Restriction Fragment Length Polymorphism (TRFLP) analysis of soil microbial communities showed that the lupine community was distinct from the other four plant-associated communities. Phospholipid fatty acid (PLFA) patterns also failed to distinguish differences in the overall microbial communities associated with the five different moncultures. Interestingly, PLFA biomarker 16:1w5, indicative of AM fungi, differed among plant species treatments. This PLFA biomarker and bacterial TRFLP patterns were related to decomposition rates of a common litter. In summary, large functional differences were found between field plots with different plant species and the composition of the microbial communities was closely related to some of the functions assessed, independent of plant species. Only small plant-induced changes in microbial community composition were detected, yet apparently these changes had significant impact on function. Our analyses were not specifically targeted to microsites with high activity (such as rhizosphere soil) and our DNA and PLFA-based analyses included a potentially huge "dormant" community of soil microorganisms. While our analyses could detect little impact of plant species on overall microbial community profiles, a smaller active-fraction of the soil microbial community may have been more significantly affected.

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



Determination of arsenic species in water, soils and plants  

Microsoft Academic Search

Ion chromatographic separation coupled with ICP-MS was used to determine arsenic species in plant and soil extracts. A scheme\\u000a for growth, harvesting, sample pre-treatment and analysis was developed for the arsenic species to enable determination. Preliminary\\u000a results obtained with ten herb plants grown on arsenic-contaminated soil compared to non-contaminated soil show a heterogeneous\\u000a pattern of accumulation rate, metabolization and detoxification

J. Mattusch; R. Wennrich; A.-C. Schmidt; W. Reisser



Proteome analysis of orphan plant species, fact or fiction?  


Biological research has focused in the past on model organisms and most of the functional genomics studies in the field of plant sciences are still performed on model species or reference species that are characterized to a great extent. However, numerous non-model plants are essential as food, feed, or energy resource. Some features and processes are unique to these plant species or families and cannot be approached via a model plant. The power of all proteomic and transcriptomic methods, i.e., high throughput identification of candidate gene products, tends to be lost in orphan species due to the lack of genomic information, the complexity of the genome (protein inference problem, polyploidy) or due to the sequence divergence to a related sequenced reference variety or to a related model organism. Nevertheless, a proteomics approach has a great potential to study orphan species. This chapter reviews concisely orphan plants from a proteomic angle and provides an outline of the problems encountered when initiating the proteome analysis of a non-model organism. We discuss briefly the problems and solutions for orphan plants associated with sample preparation and focus further on the difficulties associated with protein redundancy in polyploid species and the protein inference issue which is particularly associated with a peptide based proteomics approach. PMID:24136533

Carpentier, Sebastien C; America, Twan



Phytotoxicity of Designated Pollutants on Plant Species.  

National Technical Information Service (NTIS)

A ground cloud is formed as the space shuttle rocket lifts off. The phytotoxicity of products released from thic cloud was studied. Aluminum oxide dust and droplets of hydrogen chloride (HCl) were found on leaves of plants at the Kennedy Space Center foll...

A. L. Granett



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



Plant species differences in particulate matter accumulation on leaf surfaces.  


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




Technology Transfer Automated Retrieval System (TEKTRAN)

The mass-ratio hypothesis holds that ecosystem processes depend in the short term on functional properties of dominant plant species and in the longer term on how resident species influence the recruitment of potential dominants. The latter of these effects may be especially important among early-s...


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



A review of the antioxidant potential of medicinal plant species  

Microsoft Academic Search

Some researchers suggest that two-thirds of the world's plant species have medicinal value; in particular, many medicinal plants have great antioxidant potential. Antioxidants reduce the oxidative stress in cells and are therefore useful in the treatment of many human diseases, including cancer, cardiovascular diseases and inflammatory diseases. This paper reviews the antioxidant potential of extracts from the stems, roots, bark,

Duduku Krishnaiah; Rosalam Sarbatly; Rajesh Nithyanandam



Inhibitory effect of seven Allium plants upon three Aspergillus species  

Microsoft Academic Search

Antifungal activity and minimal fungicidal concentration (MFC) of extracts of garlic, bakeri garlic, Chinese leek, Chinese chive, scallion, onion bulb and shallot bulb against Aspergillus niger, A. flavus and A. fumigatus were examined. These Allium plants possessed antifungal activity, with garlic showing the lowest MFC. With the exception of scallion, the inhibitory effect of Allium plants against three Aspergillus species

Mei-chin Yin; Shih-ming Tsao



Suppressor of K+ transport growth defect 1 (SKD1) interacts with RING-type ubiquitin ligase and sucrose non-fermenting 1-related protein kinase (SnRK1) in the halophyte ice plant  

PubMed Central

SKD1 (suppressor of K+ transport growth defect 1) is an AAA-type ATPase that functions as a molecular motor. It was previously shown that SKD1 accumulates in epidermal bladder cells of the halophyte Mesembryanthemum crystallinum. SKD1 knock-down Arabidopsis mutants showed an imbalanced Na+/K+ ratio under salt stress. Two enzymes involved in protein post-translational modifications that physically interacted with McSKD1 were identified. McCPN1 (copine 1), a RING-type ubiquitin ligase, has an N-terminal myristoylation site that links to the plasma membrane, a central copine domain that interacts with McSKD1, and a C-terminal RING domain that catalyses protein ubiquitination. In vitro ubiquitination assay demonstrated that McCPN1 was capable of mediating ubiquitination of McSKD1. McSnRK1 (sucrose non-fermenting 1-related protein kinase) is a Ser/Thr protein kinase that contains an N-terminal STKc catalytic domain to phosphorylate McSKD1, and C-terminal UBA and KA1 domains to interact with McSKD1. The transcript and protein levels of McSnRK1 increased as NaCl concentrations increased. The formation of an SKD1–SnRK1–CPN1 ternary complex was demonstrated by yeast three-hybrid and bimolecular fluorescence complementation. It was found that McSKD1 preferentially interacts with McSnRK1 in the cytosol, and salt induced the re-distribution of McSKD1 and McSnRK1 towards the plasma membrane via the microtubule cytoskeleton and subsequently interacted with RING-type E3 McCPN1. The potential effects of ubiquitination and phosphorylation on McSKD1, such as changes in the ATPase activity and cellular localization, and how they relate to the functions of SKD1 in the maintenance of Na+/K+ homeostasis under salt stress, are discussed.

Chiang, Chih-Pin; Li, Chang-Hua; Chen, Yu-Chan; Yen, Hungchen Emilie



Hydraulic lift among native plant species in the Mojave Desert  

Microsoft Academic Search

Hydraulic lift was investigated among native plants in the Mojave Desert using in situ thermocouple psychrometers. Night lighting\\u000a and day shading experiments were used to verify the phenomenon. Hydraulic lift was detected for all species examined: five\\u000a shrub species with different rooting depths and leaf phenologies and one perennial grass species. This study was the first\\u000a to document hydraulic lift

Carolyn K. Yoder; Robert S. Nowak



Widespread plant species: natives versus aliens in our changing world  

Microsoft Academic Search

Estimates of the level of invasion for a region are traditionally based on relative numbers of native and alien species. However,\\u000a alien species differ dramatically in the size of their invasive ranges. Here we present the first study to quantify the level\\u000a of invasion for several regions of the world in terms of the most widely distributed plant species (natives

Thomas J. Stohlgren; Petr Pyšek; John Kartesz; Misako Nishino; Aníbal Pauchard; Marten Winter; Joan Pino; David M. Richardson; John R. U. Wilson; Brad R. Murray; Megan L. Phillips; Li Ming-yang; Laura Celesti-Grapow


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


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



Identification of salt-induced genes from Salicornia brachiata, an extreme halophyte through expressed sequence tags analysis.  


Salinity severely affects plant growth and development causing crop loss worldwide. We have isolated a large number of salt-induced genes as well as unknown and hypothetical genes from Salicornia brachiata Roxb. (Amaranthaceae). This is the first description of identification of genes in response to salinity stress in this extreme halophyte plant. Salicornia accumulates salt in its pith and survives even at 2 M NaCl under field conditions. For isolating salt responsive genes, cDNA subtractive hybridization was performed between control and 500 mM NaCl treated plants. Out of the 1200 recombinant clones, 930 sequences were submitted to the NCBI database (GenBank accession: EB484528 to EB485289 and EC906125 to EC906292). 789 ESTs showed matching with different genes in NCBI database. 4.8% ESTs belonged to stress-tolerant gene category and approximately 29% ESTs showed no homology with known functional gene sequences, thus classified as unknown or hypothetical. The detection of a large number of ESTs with unknown putative function in this species makes it an interesting contribution. The 90 unknown and hypothetical genes were selected to study their differential regulation by reverse Northern analysis for identifying their role in salinity tolerance. Interestingly, both up and down regulation at 500 mM NaCl were observed (21 and 10 genes, respectively). Northern analysis of two important salt tolerant genes, ASR1 (Abscisic acid stress ripening gene) and plasma membrane H+ATPase, showed the basal level of transcripts in control condition and an increase with NaCl treatment. ASR1 gene is made full length using 5' RACE and its potential role in imparting salt tolerance is being studied. PMID:19556705

Jha, Bhavanath; Agarwal, Pradeep K; Reddy, Palakolanu Sudhakar; Lal, Sanjay; Sopory, Sudhir K; Reddy, Malireddy K



Partial characterization and expression of leaf catalase in the CAM-inducible halophyte Mesembryanthemum crystallinum L.  


Catalase (CAT; EC isolated from leaves of the halophytic plant Mesembryanthemum crystallinum is characterized by a high apparent molecular mass of about 320kDa, and high resistance to denaturing agents (10% ME). SDS-treatment breaks active oligomeric CAT into the less active and putatively dimeric form of 160kDa apparent molecular mass. Three subunits are resolved after denaturing PAGE: 79, 74 and 62kDa. Higher molecular masses of subunits coincide with increased activity of CAT. M. crystallinum leaf CAT reveals a diel variation in the resistance to denaturing factors and the stability of CAT is increased in a light-dependent manner both in C(3)- and in CAM-induced plants. Unchanged level of leaf CAT transcripts is documented in the diurnal cycle of C(3) plants and after salinity-induced crassulacean acid metabolism (CAM). PMID:18203610

Niewiadomska, Ewa; Miszalski, Zbigniew



New York State Plant Ranking System for Evaluating Non-Native Plant Species for Invasiveness  

Microsoft Academic Search

PURPOSE: The purpose of the New York Invasive Plant Ranking System is to assess the invasive nature of non-native plant species that are established in NYS, and also to assess the potential invasiveness of species that are new arrivals or are not yet present. This ranking system is designed to be repeatable, based on the best available science, clearly explained

Marilyn J. Jordan; Gerry Moore; Troy W. Weldy



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


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



Which ornamental plant species effectively remove benzene from indoor air?  

NASA Astrophysics Data System (ADS)

Phytoremediation—using plants to remove toxins—is an attractive and cost effective way to improve indoor air quality. This study screened ornamental plants for their ability to remove volatile organic compounds from air by fumigating 73 plant species with 150 ppb benzene, an important indoor air pollutant that poses a risk to human health. The 10 species found to be most effective at removing benzene from air were fumigated for two more days (8 h per day) to quantify their benzene removal capacity. Crassula portulacea, Hydrangea macrophylla, Cymbidium Golden Elf., Ficus microcarpa var. fuyuensis, Dendranthema morifolium, Citrus medica var. sarcodactylis, Dieffenbachia amoena cv. Tropic Snow; Spathiphyllum Supreme; Nephrolepis exaltata cv. Bostoniensis; Dracaena deremensis cv. Variegata emerged as the species with the greatest capacity to remove benzene from indoor air.

Liu, Yan-Ju; Mu, Yu-Jing; Zhu, Yong-Guan; Ding, Hui; Crystal Arens, Nan


The SbASR-1 gene cloned from an extreme halophyte Salicornia brachiata enhances salt tolerance in transgenic tobacco.  


Salinity severely affects plant growth and development. Plants evolved various mechanisms to cope up stress both at molecular and cellular levels. Halophytes have developed better mechanism to alleviate the salt stress than glycophytes, and therefore, it is advantageous to study the role of different genes from halophytes. Salicornia brachiata is an extreme halophyte, which grows luxuriantly in the salty marshes in the coastal areas. Earlier, we have isolated SbASR-1 (abscisic acid stress ripening-1) gene from S. brachiata using cDNA subtractive hybridisation library. ASR-1 genes are abscisic acid (ABA) responsive, whose expression level increases under abiotic stresses, injury, during fruit ripening and in pollen grains. The SbASR-1 transcript showed up-regulation under salt stress conditions. The SbASR-1 protein contains 202 amino acids of 21.01-kDa molecular mass and has 79 amino acid long signatures of ABA/WDS gene family. It has a maximum identity (73 %) with Solanum chilense ASR-1 protein. The SbASR-1 has a large number of disorder-promoting amino acids, which make it an intrinsically disordered protein. The SbASR-1 gene was over-expressed under CaMV 35S promoter in tobacco plant to study its physiological functions under salt stress. T(0) transgenic tobacco seeds showed better germination and seedling growth as compared to wild type (Wt) in a salt stress condition. In the leaf tissues of transgenic lines, Na(+) and proline contents were significantly lower, as compared to Wt plant, under salt treatment, suggesting that transgenic plants are better adapted to salt stress. PMID:22639284

Jha, Bhavanath; Lal, Sanjay; Tiwari, Vivekanand; Yadav, Sweta Kumari; Agarwal, Pradeep K



Arthropod assemblages are best predicted by plant species composition.  


Insects and spiders comprise more than two-thirds of the Earth's total species diversity. There is wide concern, however, that the global diversity of arthropods may be declining even more rapidly than the diversity of vertebrates and plants. For adequate conservation planning, ecologists need to understand the driving factors for arthropod communities and devise methods, that provide reliable predictions when resources do not permit exhaustive ground surveys. Which factor most successfully predicts arthropod community structure is still a matter of debate, however. The purpose of this study was to identify the factor best predicting arthropod assemblage composition. We investigated the species composition of seven functionally different arthropod groups (epigeic spiders, grasshoppers, ground beetles, weevils, hoppers, hoverflies, and bees) at 47 sites in The Netherlands comprising a range of seminatural grassland types and one heathland type. We then compared the actual arthropod composition with predictions based on plant species composition, vegetation structure, environmental data, flower richness, and landscape composition. For this we used the recently published method of predictive co-correspondence analysis, and a predictive variant of canonical correspondence analysis, depending on the type of predictor data. Our results demonstrate that local plant species composition is the most effective predictor of arthropod assemblage composition, for all investigated groups. In predicting arthropod assemblages, plant community composition consistently outperforms both vegetation structure and environmental conditions (even when the two are combined), and also performs better than the surrounding landscape. These results run against a common expectation of vegetation structure as the decisive factor. Such expectations, however, have always been biased by the fact that until recently no methods existed that could use an entire (plant) species composition in the explanatory role. Although more recent experimental diversity work has reawakened interest in the role of plant species, these studies still have not used (or have not been able to use) entire species compositions. They only consider diversity measures, both for plant and insect assemblages, which may obscure relationships. The present study demonstrates that the species compositions of insect and plant communities are clearly linked. PMID:18459341

Schaffers, André P; Raemakers, Ivo P; Sýkora, Karlè V; Ter Braak, Cajo J F



Acclimation of plant species to elevated CO{sub 2}  

SciTech Connect

Plant species differ in assimilated carbon partitioning between starch, sucrose and hexose sugars. Soluble sugars have been implicated to play a role in downregulating rubisco and other photosynthesis enzymes on the level of transcription. In this study we compared high CO{sub 2} response of plants with different physiology. Cucumber, tobacco and sunflower were chosen as relatively good starch accumulators, spinach and sugar-beet as species with high leaf soluble sugar levels. In addition woody species cottonwood and salt cedar and one C{sub 4} species (corn) were studied. Plants were grown from seed at three CO{sub 2} levels: 330 {mu}bar, 660 {mu}bar and 1500 {mu}bar. Two soil nitrogen levels were used: one that allowed normal growth and the other that caused about 5 times growth suppression. All species except corn (C{sub 4}) showed downregulation of leaf rubisco activity. This downregulation was due to decrease of rubisco content, activation state remaining unchanged. Initial slope of AC{sub i} curve and rubisco activity were in good correlation. Low and high nitrogen plants had similar relative changes in photosynthetic activity. Final harvest onground weight correlated with CO{sub 2} uptake at growth conditions. We concluded that soluble sugars per se do not cause downregulation of leaf photosynthetic activity at high CO{sub 2}.

Olavi, K.; Ball, J.T. [Desert Research Institute, Reno, NV (United States); Seemann, J. [Univ. of Nevada, Reno, NV (United States)



Production of plant growth regulators by some Fusarium species  

Microsoft Academic Search

About 10 species ofFusarium were screened and tested for their growth regulatory activity on oat coleoptile straight growth test. Culture filtrates of\\u000a four species contained growthstimulating factors while others showed growth-inhibition responses on oat sections. On the whole,F. moniliforme was found to be produce higher stimulatory effects. Chromatographic analysis revealed the presence of several indole auxin\\u000a and gibberellin-like plant-growth regulators

M. S. Thakur; K. M. Vyas



Relationship between global warming and species richness of vascular plants  

Microsoft Academic Search

We analyzed climatological and geographical variables in 90 countries from the Northern Hemisphere to determine the significant\\u000a variability of plant species richness as it relates to broad-scale levels of global warming. This variability was quantified\\u000a by the parameters of temperature and precipitation. Of the 27 temperature variables and 13 precipitation variables, 6 variables\\u000a had negative influences on species richness while

Byung-Sun Ihm; Jeom-Sook Lee; Jong-Wook Kim; Joon-Ho Kim



Regeneration of Plants from Protoplasts of Gentiana Species (Gentian)  

Microsoft Academic Search

\\u000a \\u000a Gentiana, a member of the Gentianaceae family, is composed of 400 species widely distributed all over the world except for the African\\u000a continent. Most of them are perennial herbs and are grown in the cool mountainous regions. Several species of Gentiana are used as economically important flowers and ornamental plants. G. scabra and G. triflora, which are distributed in the

Y. TAKAHATAI; H. JOMORII; S. Miyano; H. Kunitake; M. Mii


PLANT ECOLOGICAL STRATEGIES: Some Leading Dimensions of Variation Between Species  

Microsoft Academic Search

? Abstract An important aim of plant ecology is to identify leading dimensions,of ecological variation among,species and to understand,the basis for them. Dimensions that can readily be measured would be especially useful, because they might offer a path towards improved,worldwide,synthesis across the thousands,of field experiments and ecophysiological,studies that use just a few,species each. Four dimensions,are reviewed,here. The leaf mass per

Mark Westoby; Daniel S. Falster; Angela T. Moles; Peter A. Vesk; Ian J. Wright



Allelopathic Effects of Volatile Cineoles on Two Weedy Plant Species  

Microsoft Academic Search

The volatile monoterpene analogs, 1,4-cineole and 1,8-cineole, have been identified as components of many plant essential oils, but relatively little is known about their biological activities. We compared the effects of 1,4- and 1,8-cineole on two weedy plant species by monitoring germination, mitosis, root and shoot growth, chlorophyll content, and photosynthetic efficiency. 1,4-Cineole severely inhibited growth of roots and shoots,

Joanne G. Romagni; Stacy N. Allen; Franck E. Dayan



Plant–soil feedback of native and range-expanding plant species is insensitive to temperature  

Microsoft Academic Search

Temperature change affects many aboveground and belowground ecosystem processes. Here we investigate the effect of a 5°C temperature\\u000a increase on plant–soil feedback. We compare plant species from a temperate climate region with immigrant plants that originate\\u000a from warmer regions and have recently shifted their range polewards. We tested whether the magnitude of plant–soil feedback\\u000a is affected by ambient temperature and

Roy Hendrikus Antonius van Grunsven; Wim H. van der Putten; T. Martijn Bezemer; Elmar M. Veenendaal



Plant genome archaeology: evidence for conserved ancestral chromosome segments in dicotyledonous plant species.  


We have developed genetic maps, based on expressed sequence tags (ESTs) that are homologous to Arabidopsis genes, in four dicotyledonous crop plant species from different families. A comparison of these maps with the physical map of Arabidopsis reveals common genome segments that appear to have been conserved throughout the evolution of the dicots. In the four crop species analysed these segments comprise between 16 and 33% of the Arabidopsis genome. Our findings extend the synteny patterns previously observed only within plant families, and indicate that structural and functional information from the model species will be, at least in part, applicable in crop plants with large genomes. PMID:17147746

Dominguez, Isabelle; Graziano, Enrique; Gebhardt, Christiane; Barakat, Abdelali; Berry, Simon; Arús, Pere; Delseny, Michel; Barnes, Stephen



Is the magnitude of pollen limitation in a plant community affected by pollinator visitation and plant species specialisation levels?  

Microsoft Academic Search

Pollen limitation on a plant community level has received little attention, although it might show which pollination- related traits may cause pollen limitation to vary among species. To address several central questions in plant reproductive biology, we investigated pollen limitation in 11 plant species, including visitation and specialisation levels of all species. The female reproductive success of most species within

Stein Joar Hegland; Ørjan Totland



Efficient distinction of invasive aquatic plant species from non-invasive related species using DNA barcoding.  


Biological invasions are regarded as threats to global biodiversity. Among invasive aliens, a number of plant species belonging to the genera Myriophyllum, Ludwigia and Cabomba, and to the Hydrocharitaceae family pose a particular ecological threat to water bodies. Therefore, one would try to prevent them from entering a country. However, many related species are commercially traded, and distinguishing invasive from non-invasive species based on morphology alone is often difficult for plants in a vegetative stage. In this regard, DNA barcoding could become a good alternative. In this study, 242 samples belonging to 26 species from 10 genera of aquatic plants were assessed using the chloroplast loci trnH-psbA, matK and rbcL. Despite testing a large number of primer sets and several PCR protocols, the matK locus could not be amplified or sequenced reliably and therefore was left out of the analysis. Using the other two loci, eight invasive species could be distinguished from their respective related species, a ninth one failed to produce sequences of sufficient quality. Based on the criteria of universal application, high sequence divergence and level of species discrimination, the trnH-psbA noncoding spacer was the best performing barcode in the aquatic plant species studied. Thus, DNA barcoding may be helpful with enforcing a ban on trade of such invasive species, such as is already in place in the Netherlands. This will become even more so once DNA barcoding would be turned into machinery routinely operable by a nonspecialist in botany and molecular genetics. PMID:23039943

Ghahramanzadeh, R; Esselink, G; Kodde, L P; Duistermaat, H; van Valkenburg, J L C H; Marashi, S H; Smulders, M J M; van de Wiel, C C M



The role of active oxygen species in plant signal transduction  

Microsoft Academic Search

Adequate responses to environmental changes are crucial for plant growth and survival. However, the molecular and biochemical mechanisms that orchestrate these responses are still poorly understood and the signaling networks involved remain elusive. A central role for active oxygen species (AOS) during biotic and abiotic stress responses is well-recognized, although under these situations AOS can either exacerbate damage or act

Frank Van Breusegem; Eva Vranová; James F. Dat; Dirk Inzé



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




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...


Host plant species affects virulence in monarch butterfly parasites  

Microsoft Academic Search

Summary 1. Studies have considered how intrinsic host and parasite properties determine parasite virulence, but have largely ignored the role of extrinsic ecological factors in its expression. 2. We studied how parasite genotype and host plant species interact to determine virulence of the protozoan parasite Ophryocystis elektroscirrha (McLaughlin & Myers 1970) in the monarch butterfly Danaus plexippus L. We infected

Jacobus C. de Roode; Amy B. Pedersen; Mark D. Hunter; Sonia Altizer



Plant regeneration from various expiants of cultivated Piper species  

Microsoft Academic Search

Morphogenetic potential of root, leaf, node and internode expiants of 3 cultivated Piper species was investigated to develop a reliable plant regeneration protocol. P. longum (pipli) was the most responsive followed by P. betle (betel vine) and P. nigrum (black pepper). In P. longum the highest number of shoot buds was produced on root expiants followed by node, internode and

S. R. Bhat; K. P. S. Chandel; S. K. Malik



Image processing methods for identifying species of plants  

Microsoft Academic Search

More selective methods for applying agricultural herbicides on fields can result in substantial cost savings. Three image processing methods were tested for their ability to identify four different images of plant species. First two images were different and the other two were similar. The images are preprocessed by segmentation and spatial filtering using the Color Chromaticity Chart. The test results

Shulin Dave; Ken Runtz



Plant species composition and biofuel yields of conservation grasslands  

Technology Transfer Automated Retrieval System (TEKTRAN)

Marginal croplands, such as those in the Conservation Reserve Program (CRP), have been suggested as a source of biomass for biofuel production. However, little is known about the composition of plant species on these conservation grasslands or their potential for ethanol production. Our objective w...


Impact of habitat quality on forest plant species colonization  

Microsoft Academic Search

The impact of habitat quality and site history on the recolonization potential of ancient-forest plant species on abandoned farmland was studied in the forest of Ename, Flanders, Belgium. With the exception of a network of fringe relics (linear elements mainly along exploitation roads), our study area was cleared and converted to arable land ca. 1850. From 1869 onward, most fields

Olivier Honnay; Martin Hermy; Pol Coppin



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.

Rewald, Boris; Meinen, Catharina



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.



Tissue culture as a potential method for preserving of various threatened plant species of Latvia  

Microsoft Academic Search

Summary Field collection of rare and endangered species in National Botanic Garden was started in 1981 and now 70 species of threatened plants are collected. To elaborate tissue culture technology for species conservation explants of 40 threatened plant species from natural habitats were collected. In total, 37 species were introduced in sterile conditions. For 20 species aseptic culture was initiated



Alleviatory effects of calcium on the toxicity of sodium, potassium and magnesium chlorides to seed germination in three non-halophytes  

Microsoft Academic Search

Saline soils contain numerous salts with varying impact on seed germination. Seeds of three non-halophytic species found in Chinese sandy deserts (Artemisia ordosica, Aristida adscensionis and Bassia dasyphylla) were incubated in salt solutions (NaCl, KCl or MgCl2, each with or without CaCl2) at 20°C in the dark. The effects of each salt on the percentage of seeds from which visibly

Kazuo Tobe; Liping Zhang; Kenji Omasa



Osmotic adjustment, water relations and growth attributes of the xero-halophyte Reaumuria vermiculata L. (Tamaricaceae) in response to salt stress  

Microsoft Academic Search

Reaumuria vermiculata (L.), a perennial dwarf shrub in the family of Tamaricaceae, is a salt-secreting xero-halophyte found widely in arid areas\\u000a of Tunisia. In the present study, physiological attributes of R. vermiculata were investigated under salt stress. Four-month-old plants were subjected to various salinity levels (0, 100, 200, 300, 400\\u000a or 600 mM NaCl) for 30 days under greenhouse conditions. Results showed

Mustapha Gorai; Mohamed Neffati



How many species of flowering plants are there?  


We estimate the probable number of flowering plants. First, we apply a model that explicitly incorporates taxonomic effort over time to estimate the number of as-yet-unknown species. Second, we ask taxonomic experts their opinions on how many species are likely to be missing, on a family-by-family basis. The results are broadly comparable. We show that the current number of species should grow by between 10 and 20 per cent. There are, however, interesting discrepancies between expert and model estimates for some families, suggesting that our model does not always completely capture patterns of taxonomic activity. The as-yet-unknown species are probably similar to those taxonomists have described recently-overwhelmingly rare and local, and disproportionately in biodiversity hotspots, where there are high levels of habitat destruction. PMID:20610425

Joppa, Lucas N; Roberts, David L; Pimm, Stuart L



Light dependency of VOC emissions from selected Mediterranean plant species  

NASA Astrophysics Data System (ADS)

The light, temperature and stomatal conductance dependencies of volatile organic compound (VOC) emissions from ten plant species commonly found in the Mediterranean region were studied using a fully controlled leaf cuvette in the laboratory. At standard conditions of temperature and light (30°C and 1000 ?mol m -2 s -1 PAR), low emitting species ( Arbutus unedo, Pinus halepensis, Cistus incanus, Cistus salvifolius, Rosmarinus officinalis and Thymus vulgaris) emitted between 0.1 and 5.0 ?g (C) (total VOCs) g -1 dw h -1, a medium emitter ( Pinus pinea) emitted between 5 and 10 ?g (C) g -1 dw h -1 and high emitters ( Cistus monspeliensis, Lavendula stoechas and Quercus sp.) emitted more than 10 ?g (C) g -1 dw h -1. VOC emissions from all of the plant species investigated showed some degree of light dependency, which was distinguishable from temperature dependency. Emissions of all compounds from Quercus sp. were light dependent. Ocimene was one of several monoterpene compounds emitted by P. pinea and was strongly correlated to light. Only a fraction of monoterpene emissions from C. incanus exhibited apparent weak light dependency but emissions from this plant species were strongly correlated to temperature. Data presented here are consistent with past studies, which show that emissions are independent of stomatal conductance. These results may allow more accurate predictions of monoterpene emission fluxes from the Mediterranean region to be made.

Owen, S. M.; Harley, P.; Guenther, A.; Hewitt, C. N.


Stimulated rhizodegradation of atrazine by selected plant species.  


The efficacy of vegetative buffer strips (VBS) in removing herbicides deposited from surface runoff is related to the ability of plant species to promote rapid herbicide degradation. A growth chamber study was conducted to compare C-atrazine (ATR) degradation profiles in soil rhizospheres from different forage grasses and correlate ATR degradation rates and profiles with microbial activity using three soil enzymes. The plant treatments included: (i) orchardgrass ( L.), (ii) smooth bromegrass ( Leyss.), (iii) tall fescue ( Schreb.), (iv) Illinois bundle flower (), (v) perennial ryegrass ( L.), (vi) switchgrass ( L.), and (vii) eastern gamagrass (). Soil without plants was used as the control. The results suggested that all plant species significantly enhanced ATR degradation by 84 to 260% compared with the control, but eastern gamagrass showed the highest capability for promoting biodegradation of ATR in the rhizosphere. More than 90% of ATR was degraded in the eastern gamagrass rhizosphere compared with 24% in the control. Dealkylation of atrazine strongly correlated with increased enzymatic activities of ?-glucosidase (GLU) ( = 0.96), dehydrogenase (DHG) ( = 0.842), and fluorescein diacetate (FDA) hydrolysis ( = 0.702). The incorporation of forage species, particularly eastern gamagrass, into VBS designs will significantly promote the degradation of ATR transported into the VBS by surface runoff. Microbial parameters widely used for assessment of soil quality, e.g., DHG and GLU activities, are promising tools for evaluating the overall degradation potential of various vegetative buffer designs for ATR remediation. PMID:21712580

Lin, Chung-Ho; Lerch, Robert N; Kremer, Robert J; Garrett, Harold E


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



Drought, but not salinity, determines the apparent effectiveness of halophytes colonized by arbuscular mycorrhizal fungi.  


The halophytes Plantago maritima, Aster tripolium, Artemisia santonicum, Puccinellia limosa, Festuca pseudovina and Lepidium crassifolium from two different saline soils of the Hungarian steppe were examined for colonization by arbuscular mycorrhizal fungi (AMF). The salt aster (A. tripolium) and the sea plantain (P. maritima) were examined more thoroughly by recording root colonization parameters, the salt content in the soil and monthly precipitations in 2001 and 2002. Mycorrhizal colonization was maximal in late spring to early summer and had a second peak later in the autumn. Arbuscule formation and overall mycorrhizal colonization appeared to be inversely correlated with the intensity of rainfall at the investigated sites. The results suggest that, in addition to seasonality, drought may play an important role in governing mycorrhizal activity in saline habitats. In greenhouse experiments, conditions in which AMF could overcome the inhibitory effects of sodium chloride on establishing plant-mycorrhizal symbiosis were not met. PMID:18155803

Füzy, Anna; Biró, Borbála; Tóth, Tibor; Hildebrandt, Ulrich; Bothe, Hermann



Phylogenetic placement of plant pathogenic Sclerotium species among teleomorph genera.  


Phylogenetic analyses and morphological characteristics were used to assess the taxonomic placement of eight plant-pathogenic Sclerotium species. Members of this genus produce only sclerotia and no fruiting bodies or spores, so Sclerotium species have been difficult to place taxonomically. Sequences of rDNA large subunit (LSU) and internal transcribed spacer (ITS) regions were determined for isolates of Sclerotium cepivorum, S. coffeicola, S. denigrans, S. hydrophilum, Ceratorhiza oryzae-sativae, S. perniciosum, S. rhizodes, S. rolfsii and S. rolfsii var. delphinii. Parsimony analysis grouped two species previously thought to be in the Basidiomycota, S. denigrans and S. perniciosum, within the Ascomycota; these species were found to have affinities with the teleomorph genera Sclerotinia and Stromatinia and the asexual Sclerotium cepivorum, which was known earlier to be related to Sclerotinia species. The other Sclerotium species were placed in one of two basidiomycetous groups, genera Athelia or Ceratobasidium. Based on rDNA analysis and morphology the basidiomycetous Sclerotium hydrophilum and S. rhizodes were transferred to genus Ceratorhiza, the anamorph of Ceratobasidium species. Sclerotium coffeicola was found to be close to S. rolfsii var. delphinii and S. rolfsii var. rolfsii, which was shown earlier to have an Athelia teleomorph. PMID:20361501

Xu, Zhihan; Harrington, Thomas C; Gleason, Mark L; Batzer, Jean C


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)



Halophyte Research And Development: What Needs To Be Done Next ?  

Microsoft Academic Search

Activities supported by the UNESCO Office in Doha in 2004–2005 UNESCO currently supports activities on water & ecosystems.\\u000a Since several years, UNESCO supported a number of projects that aimed to enhance the sustainable utilisation of saline water\\u000a resources. The development of cash crop halophytes, as well as methods for coastal habitat restoration, is believed to play\\u000a an important role towards

Benno BÖEr


Substrate heterogeneity and number of plant species in Everglades savannas (Florida, USA)  

Microsoft Academic Search

Environmental heterogeneity, especially that related to topography, has been proposed to influence numbers of plant species in different sized areas. Despite little variation in elevation, large numbers of vascular plant species occur in some habitats. This study explored possible relationships between number of plant species and substrateheterogeneity in two species-rich habitats, subtropical pine savannas and short-hydroperiod prairies, in the Long

Martin Schmitz; William Platt; James DeCoster



Na+/H+-transporter, H+-pumps and an aquaporin in light and heavy tonoplast membranes from organic acid and NaCl accumulating vacuoles of the annual facultative CAM plant and halophyte Mesembryanthemum crystallinum L.  


Crassulacean acid metabolism (CAM) was induced in Mesembryanthemum crystallinum L. by either NaCl- or high light (HL)- stress. This generated in mesophyll cells predominantly of NaCl-stressed plants two different types of vacuoles: the generic acidic vacuoles for malic acid accumulation and additionally less acidic ("neutral") vacuoles for NaCl sequestration. To examine differences in the tonoplast properties of the two types of vacuoles, we separated microsomal membranes of HL- and NaCl-stressed M. crystallinum plants by centrifugation in sucrose density gradients. Positive immunoreactions of a set of antibodies directed against tonoplast specific proteins and tonoplast specific ATP- and PPi-hydrolytic activity were used as markers for vacuolar membranes. With these criteria tonoplast membranes were detected in both HL- and NaCl-stressed plants in association with the characteristic low sucrose density but also at an unusual high sucrose density. In HL-stressed plants most of the ATP- and PPi-hydrolytic activity and cross reactivity with antibodies including that directed against the Na+/H+-antiporter from Arabidopsis thaliana was detected with light sucrose density. This relationship was inverted in NaCl-stressed plants; they exhibited most pump activity and immunoreactivity in the heavy fraction. The relative abundance of the heavy membrane fraction reflects the relative occurrence of "neutral" vacuoles in either HL- or NaCl-stressed plants. This suggests that tonoplasts of the "neutral" vacuoles sediment at high sucrose densities. This is consistent with the view that this type of vacuoles serves for Na+ sequestration and is accordingly equipped with a high capacity of proton pumping and Na+ uptake via the Na+/H+-antiporter. PMID:16575596

Epimashko, Svetlana; Fischer-Schliebs, Elke; Christian, Anna-Luise; Thiel, Gerhard; Lüttge, Ulrich



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


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



Plant Micropropagation and Callus Induction of Some Annual Salsola Species  

Microsoft Academic Search

Micropropagated plants of two annual haloxerophytic Asiatic Salsola species (S. pestifer and S. lanata) were obtained from zygotic embryos cultured on Murashige and Skoog (MS) agar medium supplemented with 0.5 M benzylamino-purine\\u000a (BAP) and 0.3 M indole-3-acetic acid (IAA) or with 0.5 M 6 ?, ?-dimethylallylaminopurine and 0.3 ?M IAA. The callus induction\\u000a from shoot and leaf explants derived from

B. Stefaniak; A. Wo?ny; V. Li



Constrained preferences in nitrogen uptake across plant species and environments.  


Knowledge of determining factors for nitrogen uptake preferences and how they are modified in changing environments are critical to understand ecosystem nitrogen cycling and to predict plant responses to future environmental changes. Two ¹?N tracer experiments utilizing a unique differential labelled nitrogen source were employed in both African savannas and greenhouse settings. The results demonstrated that nitrogen uptake preferences were constrained by the climatic conditions. As mainly indicated by root ?¹?N signatures at 1:1 ammonium/nitrate ratio, in the drier environments, plants preferred nitrate and in the wetter environments they preferred ammonium. Nitrogen uptake preferences were different across different ecosystems (e.g. from drier to wetter environments) even for the same species. More significantly, our experiments showed that the plant progeny continued to exhibit the same nitrogen preference as the parent plants in the field, even when removed from their native environment and the nitrogen source was changed dramatically. The climatic constraint of nitrogen uptake preference is likely influenced by ammonium/nitrate ratios in the native habitats of the plants. The constancy in nitrogen preference has important implications in predicting the success of plant communities in their response to climate change, to seed bank use and to reforestation efforts. PMID:21118424

Wang, Lixin; Macko, Stephen A



Pichia lachancei sp. nov., associated with several Hawaiian plant species.  


A description is given of Pichia lachancei sp. nov., a new species of yeast that occurs in association with several Hawaiian plant species of the genera Tetraplasandra, Cheirodendron and Clermontia. The new species is heterothallic and occurs in nature in the haploid as well as the diploid state. Upon conjugation of complementary mating types, zygotes are formed that reproduce by budding as diploid cells. When placed on sporulation medium, four hat-shaped spores are produced which are rapidly released from the ascus. Phylogenetic analysis showed that P. lachancei is most closely related to Pichia rhodanensis and Pichia jadinii. The diploid type strain of P. lachancei, isolated from rotting bark of Tetraplasandra hawaiiensis on the island of Hawaii, is strain UCD-FST 79-9T (= ATCC 201914T = CBS 8557T = NRRL Y-27008T). PMID:10425793

Phaff, H J; Starmer, W T; Kurtzman, C P



Parasite facilitates plant species coexistence in a coastal wetland.  


Outbreaks of infectious agents in natural ecosystems are on the rise. Understanding host-pathogen interactions and their impact on community composition may be central to the conservation of biological diversity. Infectious agents can convey both exploitive and facilitative effects that regulate host populations and community structure. Parasitic angiosperms are highly conspicuous in many plant communities, and they provide a tractable model for understanding parasite effects in multispecies communities. I examined host identity and variation in host infectivity of a holoparasitic vine (Cuscuta salina) within a California salt marsh. In a two-year parasite removal experiment, I measured the effect of C. salina on its most frequent host, a rare hemiparasite, and the plant community. C. salina clearly suppressed the dominant host, but rare plant fitness and plant species diversity were enhanced through indirect effects. Priority effects played a role in the strength of the outcome due to the timing of life history characteristics. The differential influence of parasites on the fecundity of multiple hosts can change population dynamics, benefit rare species, and alter community structure. The continuum of negative to positive consequences of parasitic interactions deserves more attention if we are to understand community dynamics and successfully restore tidal wetlands. PMID:18589512

Grewell, Brenda J



Sulphur phytoaccumulation in plant species characteristic of Gypsiferous soils.  


The SO4= toxicity in gypsiferous soils, which represent more than 100 million hectares worldwide, constitutes one of the major problems limiting world agricultural output. Currently, phytoremediation of SO4= is regarded, from agricultural and environmental standpoints, as one of the most effective alternatives for the decontamination and recovery of these soils. In this study, we analyzed the behavior of five plant species characteristic of gypsiferous soils (Gypsophila struthium, Helianthemun alypoides, H. squamatum, H. syriacum, and Lepidium subulatum) in order to establish the variability of these plants in terms of S-extraction mechanisms. Our results indicate that the species best adapted and with the densest population was Lepidium subulatum. This plant showed the highest concentration of total S and the greatest organic S, as well as the highest levels of amino acids and proteins. In this study, we propose that the incorporation of S into organic compounds is the essential metabolic process determining the tolerance of Lepidium subulatum to gypsiferous soils. In conclusion, the foliar accumulation of organic S could be defined a priori as one of the key characteristics in developing plants with a potential for regenerating zones with high SO4= concentrations. PMID:14750428

Ruiz, Juan M; López-Cantarero, Inmaculada; Rivero, Rosa M; Romero, Luis



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




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...



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...


Stochastic Species Turnover and Stable Coexistence in a Species-Rich, Fire-Prone Plant Community  

PubMed Central

Understanding the mechanisms that maintain diversity is important for managing ecosystems for species persistence. Here we used a long-term data set to understand mechanisms of coexistence at the local and regional scales in the Cape Floristic Region, a global hotspot of plant diversity. We used a dataset comprising 81 monitoring sites, sampled in 1966 and again in 1996, and containing 422 species for which growth form, regeneration mode, dispersal distance and abundances at both the local (site) and meta-community scales are known. We found that species presence and abundance were stable at the meta-community scale over the 30 year period but highly unstable at the local scale, and were not influenced by species' biological attributes. Moreover, rare species were no more likely to go extinct at the local scale than common species, and that alpha diversity in local communities was strongly influenced by habitat. We conclude that stochastic environmental fluctuations associated with recurrent fire buffer populations from extinction, thereby ensuring stable coexistence at the meta-community scale by creating a “neutral-like” pattern maintained by niche-differentiation.

Thuiller, Wilfried; Slingsby, Jasper A.; Privett, Sean D. J.; Cowling, Richard M.



Hydroperiod regime controls the organization of plant species in wetlands  

PubMed Central

With urban, agricultural, and industrial needs growing throughout the past decades, wetland ecosystems have experienced profound changes. Most critically, the biodiversity of wetlands is intimately linked to its hydrologic dynamics, which in turn are being drastically altered by ongoing climate changes. Hydroperiod regimes, e.g., percentage of time a site is inundated, exert critical control in the creation of niches for different plant species in wetlands. However, the spatial signatures of the organization of plant species in wetlands and how the different drivers interact to yield such signatures are unknown. Focusing on Everglades National Park (ENP) in Florida, we show here that cluster sizes of each species follow a power law probability distribution and that such clusters have well-defined fractal characteristics. Moreover, we individuate and model those signatures via the interplay between global forcings arising from the hydroperiod regime and local controls exerted by neighboring vegetation. With power law clustering often associated with systems near critical transitions, our findings are highly relevant for the management of wetland ecosystems. In addition, our results show that changes in climate and land management have a quantifiable predictable impact on the type of vegetation and its spatial organization in wetlands.

Foti, Romano; del Jesus, Manuel; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio



Nicotiana glauca: another plant species containing vitamin D(3) metabolites.  


Vitamin D(3)-related compounds have been detected in various plant species, mostly belonging to the Solanaceae. In this work we show that Nicotiana glauca, a widespread member of this taxonomic family, contains 7-dehydrocholesterol, vitamin D(3) and hydroxylated derivatives bearing precursor-product metabolic relationships in vertebrates. Leaves collected in the field and callus cultures were used. By means of specific radioreceptor binding assays and mass spectrometry of purified fractions obtained from plant tissue lipid extracts by Sephadex LH-20 and Sep-Pak C18 chromatography followed by HPLC, we established the presence of 7-dehydrocholesterol, vitamin D(3), 25(OH)-vitamin D(3) and 1alpha,25(OH)(2)-vitamin D(3) (1alpha,25(OH)(2)D(3)), the latter being a hormonally relevant metabolite in animals. These results indicate that N. glauca may represent a useful species in which to characterize the biosynthetic pathway and physiological functions of vitamin D(3) compounds in plants. In addition, tissue culture of N. glauca could become a significant tool for biotechnological production of 1alpha,25(OH)(2)D(3). PMID:10936526

Skliar; Curino; Milanesi; Benassati; Boland



Spatially complex neighboring relationships among grassland plant species as an effective mechanism of defense against herbivory  

Microsoft Academic Search

Close spatial relationships between plant species are often important for defense against herbivory. The associational plant\\u000a defense may have important implications for plant community structure, species diversity, and species coexistence. An increasing\\u000a number of studies have focused on associational plant defense against herbivory at the scale of the individual plant and its\\u000a nearest neighbors. However, the average neighborhood effects between

Ling Wang; Deli Wang; Yuguang Bai; Yue Huang; Meng Fan; Jushan Liu; Yexing Li



Treatment of Domestic Wastewater by Three Plant Species in Constructed Wetlands  

Microsoft Academic Search

Three common Appalachian plant species (Juncus effusus L., Scirpus validus L., and Typha latifolia L.) were planted into small-scale constructed wetlands receivingprimary treated wastewater. The experimental design includedtwo wetland gravel depths (45 and 60 cm) and five plantingtreatments (each species in monoculture, an equal mixture of the three species, and controls without vegetation), with two replicates per depth × planting

Jerry Coleman; Keith Hench; Keith Garbutt; Alan Sexstone; Gary Bissonnette; Jeff Skousen



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.

Tripathy, Baishnab Charan; Oelmuller, Ralf



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


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



Status of Endangered and Threatened Plant Species on Nevada Test Site: A Survey. Part 1. Endangered Species.  

National Technical Information Service (NTIS)

Eight plant species which occur on NTS and one which occurs just outside the west boundary have been suggested by the Fish and Wildlife Service (FWS) as endangered plants in Nevada under the Endangered Species Act of 1973. This survey provides a basis for...

W. A. Rhoads M. P. Williams



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




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

Code of Federal Regulations, 2010 CFR

...native mammals, birds, and plants. 670.25 Section 670...Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Specially Protected Species of Mammals, Birds, and Plants § 670.25...



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

Code of Federal Regulations, 2010 CFR

...native mammals, birds, and plants. 670.25 Section 670...Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Specially Protected Species of Mammals, Birds, and Plants § 670.25...



Biodiversity, exotic plant species, and herbivory: The good, the bad, and the ungulate  

Microsoft Academic Search

Invasion of natural ecosystems by exotic plant species is a major threat to biodiversity. Disturbance to native plant communities, whether natural or management induced, is a primary factor contributing to successful invasion by exotic plant species. Herbivory by both wild and domestic ungulates exerts considerable impact on structure and composition of native plant communities. Intensive herbivory by ungulates can enhance

Marty Vavra; Catherine G. Parks; Michael J. Wisdom



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.

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



Penicillium species endophytic in coffee plants and ochratoxin A production.  


Tissues from Coffea arabica, C. congensis, C. dewevrei and C. liberica collected in Colombia, Hawaii and at a local plant nursery in Maryland were sampled for the presence of fungal endophytes. Surface sterilized tissues including roots, leaves, stems and various berry parts were plated on yeast-malt agar. DNA was extracted from a set of isolates visually recognized as Penicillium, and the internal transcribed spacer region and partial LSU-rDNA was amplified and sequenced. Comparison of DNA sequences with GenBank and unpublished sequences revealed the presence of 11 known Penicillium species: P. brevicompactum, P. brocae, P. cecidicola, P. citrinum, P. coffeae, P. crustosum, P. janthinellum, P. olsonii, P. oxalicum, P. sclerotiorum and P. steckii as well as two possibly undescribed species near P. diversum and P. roseopurpureum. Ochratoxin A was produced by only four isolates, one isolate each of P. brevicompactum, P. crustosum, P. olsonii and P. oxalicum. The role these endophytes play in the biology of the coffee plant remains enigmatic. PMID:16800302

Vega, Fernando E; Posada, Francisco; Peterson, Stephen W; Gianfagna, Thomas J; Chaves, Fabio


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



Rising from the Sea: Correlations between Sulfated Polysaccharides and Salinity in Plants  

PubMed Central

High salinity soils inhibit crop production worldwide and represent a serious agricultural problem. To meet our ever-increasing demand for food, it is essential to understand and engineer salt-resistant crops. In this study, we evaluated the occurrence and function of sulfated polysaccharides in plants. Although ubiquitously present in marine algae, the presence of sulfated polysaccharides among the species tested was restricted to halophytes, suggesting a possible correlation with salt stress or resistance. To test this hypothesis, sulfated polysaccharides from plants artificially and naturally exposed to different salinities were analyzed. Our results revealed that the sulfated polysaccharide concentration, as well as the degree to which these compounds were sulfated in halophytic species, were positively correlated with salinity. We found that sulfated polysaccharides produced by Ruppia maritima Loisel disappeared when the plant was cultivated in the absence of salt. However, subjecting the glycophyte Oryza sativa Linnaeus to salt stress did not induce the biosynthesis of sulfated polysaccharides but increased the concentration of the carboxylated polysaccharides; this finding suggests that negatively charged cell wall polysaccharides might play a role in coping with salt stress. These data suggest that the presence of sulfated polysaccharides in plants is an adaptation to high salt environments, which may have been conserved during plant evolution from marine green algae. Our results address a practical biological concept; additionally, we suggest future strategies that may be beneficial when engineering salt-resistant crops.

Aquino, Rafael S.; Grativol, Clicia; Mourao, Paulo A. S.



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


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



Cytoprotective and antioxidant effects of the edible halophyte Sarcocornia perennis L. (swampfire) against lead-induced toxicity in renal cells.  


Lead (Pb) exposure is considered as a risk factor responsible for renal impairment in humans. On the other hand, the halophyte Sarcocornia perennis is a fresh vegetable crop suitable for leafy vegetable production. This study was designed to evaluate the in vitro protective activity of S. perennis against lead-induced damages in HEK293 kidney cells. Morphological and biochemical indicators were used to assess cytotoxicity and oxidative damages caused by Pb treatment on the cells. Our results showed that lead induced (1) a decrease in cell viability (MTT), (2) cell distortion and cohesion loss, (3) superoxide anion production and lipid peroxidation. Conversely, addition of S. perennis extract to the lead-containing medium alleviated every above syndrome. Thus, cell survival was increased and the production of reactive oxygen species caused by Pb treatment was inhibited. Taken together, our study revealed that S. perennis has potent cytoprotective effect against Pb-induced toxicity in HEK 293 cell. Such action would proceed through the decrease in ROS levels and resulting oxidative stress, which suggests a potential interest of this halophyte in the treatment of oxidative-stress related diseases. PMID:23755863

Gargouri, Manel; Magné, Christian; Dauvergne, Xavier; Ksouri, Riadh; El Feki, Abdelfattah; Metges, Marie-Agnès Giroux; Talarmin, Hélène



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


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



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



Plant species composition in green spaces within the built-up areas of Beijing, China  

Microsoft Academic Search

Plant species composition is a critical issue in ecological research. Studies on the characteristics of plant species composition\\u000a in the built-up areas, however, are hampered by a lack of basic field-based investigation. In this article, the plant species\\u000a composition in the built-up areas of Beijing, China, is investigated using abundant field observations. The origin of species,\\u000a chorological spectra, life forms

Juanjuan ZhaoZhiyun OuyangHua Zheng; Zhiyun Ouyang; Hua Zheng; Weiqi Zhou; Xiaoke Wang; Weihua Xu; Yongming Ni



Protein profiling of epidermal bladder cells from the halophyte Mesembryanthemum crystallinum.  


Plant epidermal trichomes are as varied in morphology as they are in function. In the halophyte Mesembryanthemum crystallinum, specialized trichomes called epidermal bladder cells (EBC) line the surface of leaves and stems, and increase dramatically in size and volume upon plant salt-treatment. These cells have been proposed to have roles in plant defense and UV protection, but primarily in sodium sequestration and as water reservoirs. To gain further understanding into the roles of EBC, a cell-type-specific proteomics approach was taken in which precision single-cell sampling of cell sap from individual EBC was combined with shotgun peptide sequencing (LC-MS/MS). Identified proteins showed diverse biological functions and cellular locations, with a high representation of proteins involved in H(+)-transport, carbohydrate metabolism, and photosynthesis. The proteome of EBC provides insight into the roles of these cells in ion and water homeostasis and raises the possibility that they are photosynthetically active and functioning in Crassulacean acid metabolism. PMID:22848050

Barkla, Bronwyn J; Vera-Estrella, Rosario; Pantoja, Omar



Plant growth inhibitor from the Malaysian medicinal plant Goniothalamus andersonii and related species.  


A crude methanol extract of Goniothalamus andersonii J. Sinclair strongly inhibited elongation of lettuce (Lactuca sativa L.) radicles. We conducted bioassay-guided purification of G. andersonii bark extract and obtained goniothalamin as the major bioactive compound. Its EC50 values against elongation of lettuce radicles and hypocotyls were 50 and 125 micromol L(-1), respectively. Among the six species tested, timothy was the most sensitive to goniothalamin. Quantification of this compound in other Goniothalamus species suggested that the plant inhibitory activity of this genus is explainable by goniothalamin, with G. calcareus as an exception. PMID:23074907

Takemura, Tomoko; Kamo, Tsunashi; Ismil, Raihan; Bakar, Baki; Wasano, Naoya; Hiradate, Syuntaro; Fujii, Yoshiharu



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.



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



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.



Interaction of Plant Species Diversity on Grazing Behavior and Performance of Livestock Grazing Temperate Region Pastures  

Microsoft Academic Search

The importance of plant species diversity on performance of live- stock grazing temperate region pastures is summarized in this review. As livestock producers seek less capital-intensive production systems, emphasis is redirected toward low-input pasture systems that rely on complex species mixtures to produce forage. Increased plant species diversity has been linked to improvements in ecosystem function. While it is recognized

K. J. Soder; A. J. Rook; M. A. Sanderson; S. C. Goslee



Release of zinc mobilizing root exudates in different plant species as affected by zinc nutritional status  

Microsoft Academic Search

The effect of zinc nutritional status of the plant on the release of zinc mobilizing root exudates was studied in various dicotyledonous (apple, bean, cotton, sunflower, tomato) and graminaceous (barley, wheat) plant species grown in nutrient solutions. In all species, zinc deficiency increased root exudation of amino acids, sugars and phenolics. However, the root exudates of zinc deficient dicotyledonous species

Fusuo Zhang; Volker Romheld; Horst Marschner



Faster returns on 'leaf economics' and different biogeochemical niche in invasive compared with native plant species  

Microsoft Academic Search

Plant-invasive success is one of the most important current global changes in the biosphere. To understand which factors explain such success, we compared the foliar traits of 41 native and 47 alien-invasive plant species in Oahu Island (Hawaii), a location with a highly endemic flora that has evolved in isolation and is currently vulnerable to invasions by exotic plant species.



Mercury bioaccumulation and phytotoxicity in two wild plant species of Almadén area  

Microsoft Academic Search

Mercury is a widely distributed environmental pollutant, able to induce toxicity in living organisms, including higher plants. Some plant species are able to grow in mine sites, like the Almadén zone in Spain. Our study focus on two of these plant species, Rumex induratus and Marrubium vulgare and their responses to natural Hg exposure. Total Hg concentration in the soil

E. Moreno-Jiménez; R. Gamarra; R. O. Carpena-Ruiz; R. Millán; J. M. Peñalosa; E. Esteban



Susceptibility of Common and Rare Plant Species to the Genetic Consequences of Habitat Fragmentation  

Microsoft Academic Search

Small plant populations are more prone to extinction due to the loss of genetic variation through random genetic drift, increased selfing, and mating among related individuals. To date, most researchers deal- ing with genetic erosion in fragmented plant populations have focused on threatened or rare species. We raise the question whether common plant species are as susceptible to habitat fragmentation




Bioactive natural products derived from polygonum species of plants: their structures and mechanisms of action  

Microsoft Academic Search

This review encompasses the natural products literature (with the exception of the patent literature or conference abstracts) of some of the different species of plants in the Polygonum species. Some of the plants in this genus originated in Japan and were later introduced to other parts of the world. These plants are commonly used in Chinese and Japanese folk medicine

Nwaka Ogwuru; Madeline Adamczeski



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



Antioxidative response mechanisms in halophytes: Their role in stress defence  

Microsoft Academic Search

Normal growth and development of plants is greatly dependent on the capacity to overcome environmental stresses. Environmental\\u000a stress conditions like high salinity, drought, high incident light and low or high temperature cause major crop losses worldwide.\\u000a A common denominator in all these adverse conditions is the production of reactive oxygen species (ROS) within different cellular\\u000a compartments of the plant cell.

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



Distribution fitting 13. Analysis of independent, multiplicative effect of factors. Application to effect of essential oils extracts from plant species on bacterial species. Application to factors of antibacterial activity of plant species  

Microsoft Academic Search

A factor effect study was conducted on a set of observations at the contingency of a series of plant species and bacteria species regarding the antibacterial activity of essential oil extracts. The study reveals a very good agreement between the observations and the hypothesis of independent and multiplicative effect of plant and bacteria species factors on the antibacterial activity. Shaping

Lorentz Jäntschi; Sorana D. Bolboacba; Mugur C. Bbalan; Radu E. Sestras



Plant trait-species abundance relationships vary with environmental properties in subtropical forests in eastern china.  


Understanding how plant trait-species abundance relationships change with a range of single and multivariate environmental properties is crucial for explaining species abundance and rarity. In this study, the abundance of 94 woody plant species was examined and related to 15 plant leaf and wood traits at both local and landscape scales involving 31 plots in subtropical forests in eastern China. Further, plant trait-species abundance relationships were related to a range of single and multivariate (PCA axes) environmental properties such as air humidity, soil moisture content, soil temperature, soil pH, and soil organic matter, nitrogen (N) and phosphorus (P) contents. At the landscape scale, plant maximum height, and twig and stem wood densities were positively correlated, whereas mean leaf area (MLA), leaf N concentration (LN), and total leaf area per twig size (TLA) were negatively correlated with species abundance. At the plot scale, plant maximum height, leaf and twig dry matter contents, twig and stem wood densities were positively correlated, but MLA, specific leaf area, LN, leaf P concentration and TLA were negatively correlated with species abundance. Plant trait-species abundance relationships shifted over the range of seven single environmental properties and along multivariate environmental axes in a similar way. In conclusion, strong relationships between plant traits and species abundance existed among and within communities. Significant shifts in plant trait-species abundance relationships in a range of environmental properties suggest strong environmental filtering processes that influence species abundance and rarity in the studied subtropical forests. PMID:23560114

Yan, En-Rong; Yang, Xiao-Dong; Chang, Scott X; Wang, Xi-Hua



Plant Trait-Species Abundance Relationships Vary with Environmental Properties in Subtropical Forests in Eastern China  

PubMed Central

Understanding how plant trait-species abundance relationships change with a range of single and multivariate environmental properties is crucial for explaining species abundance and rarity. In this study, the abundance of 94 woody plant species was examined and related to 15 plant leaf and wood traits at both local and landscape scales involving 31 plots in subtropical forests in eastern China. Further, plant trait-species abundance relationships were related to a range of single and multivariate (PCA axes) environmental properties such as air humidity, soil moisture content, soil temperature, soil pH, and soil organic matter, nitrogen (N) and phosphorus (P) contents. At the landscape scale, plant maximum height, and twig and stem wood densities were positively correlated, whereas mean leaf area (MLA), leaf N concentration (LN), and total leaf area per twig size (TLA) were negatively correlated with species abundance. At the plot scale, plant maximum height, leaf and twig dry matter contents, twig and stem wood densities were positively correlated, but MLA, specific leaf area, LN, leaf P concentration and TLA were negatively correlated with species abundance. Plant trait-species abundance relationships shifted over the range of seven single environmental properties and along multivariate environmental axes in a similar way. In conclusion, strong relationships between plant traits and species abundance existed among and within communities. Significant shifts in plant trait-species abundance relationships in a range of environmental properties suggest strong environmental filtering processes that influence species abundance and rarity in the studied subtropical forests.

Yan, En-Rong; Yang, Xiao-Dong; Chang, Scott X.; Wang, Xi-Hua



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



Increased Plant Carbon Translocation Linked to Overyielding in Grassland Species Mixtures  

PubMed Central

Plant species richness and productivity often show a positive relationship, but the underlying mechanisms are not fully understood, especially at the plant species level. We examined how growing plants in species mixture influences intraspecific rates of short-term carbon (C-) translocation, and determined whether such short-term responses are reflected in biomass yields. We grew monocultures and mixtures of six common C3 grassland plant species in outdoor mesocosms, applied a 13C-CO2 pulse in situ to trace assimilated C through plants, into the soil, and back to the atmosphere, and quantified species-specific biomass. Pulse derived 13C enrichment was highest in the legumes Lotus corniculatus and Trifolium repens, and relocation (i.e. transport from the leaves to other plant parts) of the recently assimilated 13C was most rapid in T. repens grown in 6-species mixtures. The grass Anthoxanthum odoratum also showed high levels of 13C enrichment in 6-species mixtures, while 13C enrichment was low in Lolium perenne, Plantago lanceolata and Achillea millefolium. Rates of C loss through respiration were highest in monocultures of T. repens and relatively low in species mixtures, while the proportion of 13C in the respired CO2 was similar in monocultures and mixtures. The grass A. odoratum and legume T. repens were most promoted in 6-species mixtures, and together with L. corniculatus, caused the net biomass increase in 6-species mixtures. These plant species also had highest rates of 13C-label translocation, and for A. odoratum and T. repens this effect was greatest in plant individuals grown in species mixtures. Our study reveals that short-term plant C translocation can be accelerated in plant individuals of legume and C3 grass species when grown in mixtures, and that this is strongly positively related to overyielding. These results demonstrate a mechanistic coupling between changes in intraspecific plant carbon physiology and increased community level productivity in grassland systems.

De Deyn, Gerlinde B.; Quirk, Helen; Oakley, Simon; Ostle, Nick J.; Bardgett, Richard D.



Increased plant carbon translocation linked to overyielding in grassland species mixtures.  


Plant species richness and productivity often show a positive relationship, but the underlying mechanisms are not fully understood, especially at the plant species level. We examined how growing plants in species mixture influences intraspecific rates of short-term carbon (C-) translocation, and determined whether such short-term responses are reflected in biomass yields. We grew monocultures and mixtures of six common C3 grassland plant species in outdoor mesocosms, applied a (13)C-CO(2) pulse in situ to trace assimilated C through plants, into the soil, and back to the atmosphere, and quantified species-specific biomass. Pulse derived (13)C enrichment was highest in the legumes Lotus corniculatus and Trifolium repens, and relocation (i.e. transport from the leaves to other plant parts) of the recently assimilated (13)C was most rapid in T. repens grown in 6-species mixtures. The grass Anthoxanthum odoratum also showed high levels of (13)C enrichment in 6-species mixtures, while (13)C enrichment was low in Lolium perenne, Plantago lanceolata and Achillea millefolium. Rates of C loss through respiration were highest in monocultures of T. repens and relatively low in species mixtures, while the proportion of (13)C in the respired CO(2) was similar in monocultures and mixtures. The grass A. odoratum and legume T. repens were most promoted in 6-species mixtures, and together with L. corniculatus, caused the net biomass increase in 6-species mixtures. These plant species also had highest rates of (13)C-label translocation, and for A. odoratum and T. repens this effect was greatest in plant individuals grown in species mixtures. Our study reveals that short-term plant C translocation can be accelerated in plant individuals of legume and C3 grass species when grown in mixtures, and that this is strongly positively related to overyielding. These results demonstrate a mechanistic coupling between changes in intraspecific plant carbon physiology and increased community level productivity in grassland systems. PMID:23049893

De Deyn, Gerlinde B; Quirk, Helen; Oakley, Simon; Ostle, Nick J; Bardgett, Richard D



Medium-term fertilization of grassland plant communities masks plant species-linked effects on soil microbial community structure  

Microsoft Academic Search

According to the singular hypothesis of plant diversity, different plant species are expected to make unique contributions\\u000a to ecosystem functioning. Hence, individual species would support distinct microbial communities. It was hypothesized that\\u000a microbial community dynamics in the respective rhizospheres of, two floristically divergent species, Agrostis capillaris and Prunella vulgaris that were dominant in a temperate, upland grassland in northern Greece,

Stavros D. Veresoglou; Andreas P. Mamolos; Barry Thornton; Olga K. Voulgari; Robin Sen; Demetrios S. Veresoglou



Comparative genomic analysis of 1047 completely sequenced cDNAs from an Arabidopsis-related model halophyte, Thellungiella halophila  

PubMed Central

Background Thellungiella halophila (also known as T. salsuginea) is a model halophyte with a small size, short life cycle, and small genome. Thellungiella genes exhibit a high degree of sequence identity with Arabidopsis genes (90% at the cDNA level). We previously generated a full-length enriched cDNA library of T. halophila from various tissues and from whole plants treated with salinity, chilling, freezing stress, or ABA. We determined the DNA sequences of 20 000 cDNAs at both the 5'- and 3' ends, and identified 9569 distinct genes. Results Here, we completely sequenced 1047 Thellungiella full-length cDNAs representing abiotic-stress-related genes, transcription factor genes, and protein phosphatase 2C genes. The predicted coding sequences, 5'-UTRs, and 3'-UTRs were compared with those of orthologous genes from Arabidopsis for length, sequence similarity, and structure. The 5'-UTR sequences of Thellungiella and Arabidopsis orthologs shared a significant level of similarity, although the motifs were rearranged. While examining the stress-related Thellungiella coding sequences, we found a short splicing variant of T. halophila salt overly sensitive 1 (ThSOS1), designated ThSOS1S. ThSOS1S contains the transmembrane domain of ThSOS1 but lacks the C-terminal hydrophilic region. The expression level of ThSOS1S under normal growth conditions was higher than that of ThSOS1. We also compared the expression levels of Na+-transport-system genes between Thellungiella and Arabidopsis by using full-length cDNAs from each species as probes. Several genes that play essential roles in Na+ excretion, compartmentation, and diffusion (SOS1, SOS2, NHX1, and HKT1) were expressed at higher levels in Thellungiella than in Arabidopsis. Conclusions The full-length cDNA sequences obtained in this study will be essential for the ongoing annotation of the Thellungiella genome, especially for further improvement of gene prediction. Moreover, they will enable us to find splicing variants such as ThSOS1S (AB562331).



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

Code of Federal Regulations, 2011 CFR

...Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Specially Protected Species of Mammals, Birds, and Plants § 670.25 Designation of specially...



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

Code of Federal Regulations, 2012 CFR

...Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION CONSERVATION OF ANTARCTIC ANIMALS AND PLANTS Specially Protected Species of Mammals, Birds, and Plants § 670.25 Designation of specially...



Plant species distribution in relation to water-table depth and soil ...  


International Institute of Tropical Forestry ... Title: Plant species distribution in relation to water-table depth and soil redox potential in ... riparian plant communities¡ªdefined as wet, moist, and dry meadow¡ªalong short topographic gradients.


Species Diversity of Edible Plants Grown in Homegardens of Chibchan Amerindians from Costa Rica  

Microsoft Academic Search

We studied edible crop species diversity at homegardens of two Chibchan Amerindian Reserves in Costa Rica: Talamanca and Coto Brus. We visited six settlements at Talamanca and five at Coto Brus. We recorded the number of edible crop species growing homegardens; we found 46 edible plant species at Talamanca and 27 at Coto Brus. The mean number of species per

Maria E. Zaldivar; Oscar J. Rocha; Emilio Castro; Ramiro Barrantes



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

Microsoft Academic Search

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

Iris Koch; Lixia Wang; Chris A. Ollson; William R. Cullen; Kenneth J. Reimer



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


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



Interactions between alien plant species traits and habitat characteristics in agricultural landscapes in Finland  

Microsoft Academic Search

The survival and success of alien plant species is determined by species traits (i.e., invasiveness) and the characteristics\\u000a of the habitats in the region of introduction (i.e., invasibility). However, little is known about species traits as related\\u000a to habitat characteristics. We assessed the characteristics of successful invaders and the interaction of environmental factors\\u000a and life-history traits for alien plant species.

Miia Jauni; Terho Hyvönen


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



Improved drought and salt stress tolerance in transgenic tobacco overexpressing a novel A20\\/AN1 zinc-finger “AlSAP” gene isolated from the halophyte grass Aeluropus littoralis  

Microsoft Academic Search

We describe here the isolation of a novel gene, designated AlSAP, from A. littoralis in a first step to exploit the potential of this halophyte grass as a genetic resource to improve salt and drought tolerance\\u000a in plants and, particularly, in cereals. The Aeluropus genome contains a single AlSAP gene which has an intron at its 5’UTR. Sequence homology analysis

Rania Ben Saad; Nabil Zouari; Walid Ben Ramdhan; Jalel Azaza; Donaldo Meynard; Emmanuel Guiderdoni; Afif Hassairi



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.



Fungal endophytes in five medicinal plant species from Kudremukh Range, Western Ghats of India.  


Eighteen species of endophytic fungi were isolated from bark, stem and leaf segments of five medicinal plant species growing within the Kudremukh range in the Western Ghats of India. The dominant endophytic fungal species isolated from these plant species were Curvularia clavata, C. lunata, C. pallescens and Fusarium oxysporum. The highest species richness as well as frequency of colonization of endophytic fungi was found in the leaf segments, rather than the stem and bark segments, of the host plant species. The greatest number of endophytic fungal species were found within Callicarpa tomentosa (11 species), whereas Lobelia nicotinifolia harbored the lowest number of fungal endophytes (5 species). This study provides evidence that fungal endophytes are host and tissue specific. PMID:15900544

Raviraja, N S



SbDREB2A, an A-2 type DREB transcription factor from extreme halophyte Salicornia brachiata confers abiotic stress tolerance in Escherichia coli  

Microsoft Academic Search

Dehydration-responsive element binding (DREB) transcription factor plays a key role in plant stress signal transduction pathway.\\u000a In this study, SbDREB2A has been isolated from the halophyte Salicornia brachiata. SbDREB2A cDNA is 1,062 bp long, encoding protein of 353 amino acids with an estimated molecular mass of 39.37 kDa and a pI of 4.98. On the basis of multiple sequence alignment and phylogenetic

Kapil Gupta; Pradeep K. Agarwal; M. K. Reddy; Bhavanath Jha



GLK gene pairs regulate chloroplast development in diverse plant species.  


Chloroplast biogenesis is a complex process that requires close co-ordination between two genomes. Many of the proteins that accumulate in the chloroplast are encoded by the nuclear genome, and the developmental transition from proplastid to chloroplast is regulated by nuclear genes. Here we show that a pair of Golden 2-like (GLK) genes regulates chloroplast development in Arabidopsis. The GLK proteins are members of the GARP superfamily of transcription factors, and phylogenetic analysis demonstrates that the maize, rice and Arabidopsis GLK gene pairs comprise a distinct group within the GARP superfamily. Further phylogenetic analysis suggests that the gene pairs arose through separate duplication events in the monocot and dicot lineages. As in rice, AtGLK1 and AtGLK2 are expressed in partially overlapping domains in photosynthetic tissue. Insertion mutants demonstrate that this expression pattern reflects a degree of functional redundancy as single mutants display normal phenotypes in most photosynthetic tissues. However, double mutants are pale green in all photosynthetic tissues and chloroplasts exhibit a reduction in granal thylakoids. Products of several genes involved in light harvesting also accumulate at reduced levels in double mutant chloroplasts. GLK genes therefore regulate chloroplast development in diverse plant species. PMID:12220263

Fitter, David W; Martin, David J; Copley, Martin J; Scotland, Robert W; Langdale, Jane A



Reactive oxygen species mediate growth and death in submerged plants  

PubMed Central

Aquatic and semi-aquatic plants are well adapted to survive partial or complete submergence which is commonly accompanied by oxygen deprivation. The gaseous hormone ethylene controls a number of adaptive responses to submergence including adventitious root growth and aerenchyma formation. Reactive oxygen species (ROS) act as signaling intermediates in ethylene-controlled submergence adaptation and possibly also independent of ethylene. ROS levels are controlled by synthesis, enzymatic metabolism, and non-enzymatic scavenging. While the actors are by and large known, we still have to learn about altered ROS at the subcellular level and how they are brought about, and the signaling cascades that trigger a specific response. This review briefly summarizes our knowledge on the contribution of ROS to submergence adaptation and describes spectrophotometrical, histochemical, and live cell imaging detection methods that have been used to study changes in ROS abundance. Electron paramagnetic resonance (EPR) spectroscopy is introduced as a method that allows identification and quantification of specific ROS in cell compartments. The use of advanced technologies such as EPR spectroscopy will be necessary to untangle the intricate and partially interwoven signaling networks of ethylene and ROS.

Steffens, Bianka; Steffen-Heins, Anja; Sauter, Margret



Invasive plant species as potential bioenergy producers and carbon contributors.  

SciTech Connect

Current cellulosic bioenergy sources in the United States are being investigated in an effort to reduce dependence on foreign oil and the associated risks to national security and climate change (Koh and Ghazoul 2008; Demirbas 2007; Berndes et al. 2003). Multiple sources of renewable plant-based material have been identified and include agricultural and forestry residues, municipal solid waste, industrial waste, and specifically grown bioenergy crops (Demirbas et al. 2009; Gronowska et al. 2009). These sources are most commonly converted to energy through direct burning, conversion to gas, or conversion to ethanol. Annual crops, such as corn (Zea Mays L.) and sorghum grain, can be converted to ethanol through fermentation, while soybean and canola are transformed into fatty acid methyl esters (biodiesel) by reaction with an alcohol (Demirbas 2007). Perennial grasses are one of the more viable sources for bioenergy due to their continuous growth habit, noncrop status, and multiple use products (Lewandowski el al. 2003). In addition, a few perennial grass species have very high water and nutrient use efficiencies producing large quantities of biomass on an annual basis (Dohleman et al. 2009; Grantz and Vu 2009).

Young, S.; Gopalakrishnan, G.; Keshwani, D. (Energy Systems); (Univ. of Nebraska)



Species removal and experimental warming in a subarctic tundra plant community.  


Neighbor interactions are likely to play an important role in subarctic plant communities. We conducted experiments in Interior Alaska in which we crossed species removal with greenhouse warming manipulations. We examined changes in community biomass, and in plant survival and growth of individual species in response to experimental warming and to: (1) removal of whole species versus an equivalent amount of biomass across many species, and (2) removal of subdominant (locally common) versus minor (locally uncommon) plants. Community biomass indicated compensation in growth after removal of minor species and after biomass removal without elimination of entire species, but under-compensation after removal of subdominants. Growth and survival of individual species showed facilitation between some species. Warming increased growth of dominant vascular plants, but at the same time reduced survival, and these impacts were greater for larger, more mesic species than for the smaller species associated with drier habitats. Growth of mosses was reduced by the warming. Removal effects did not differ between warming and ambient conditions. The results indicate that common species are able to reduce resources for others (competitive effect) and increase their growth after neighbor removal, whereas locally uncommon species are not able to respond rapidly to increased resources made available by neighbor removal. Therefore, the impact of the presence of common species on locally uncommon species was facilitative overall, but not vice versa. The balance between disturbances such as changes in temperature and species losses from the community will likely be crucial in determining shifts in subsequent community composition. PMID:19479282

Rixen, Christian; Mulder, Christa P H



Why does salinity pose such a difficult problem for plant breeders?  

Microsoft Academic Search

The dominance of salt water across the surface of the earth has lead to the widespread occurrence of salt-affected soils. Salt-tolerant plants (halophytes) have evolved to grow on these soils, with halophytes and less tolerant plants showing a wide range of adaptations. However, most of our crops are salt-sensitive. Consequently, salinity is an ever-present threat to agriculture, especially in areas

T. J. Flowers; S. A. Flowers



Interactions of plant zinc and plant species on the bioavailability of plant cadmium to Japanese quail fed lettuce and spinach  

SciTech Connect

Many cadmium-contaminated environments contain high levels of zinc. The effects of plant Zn and plant species on plant Cd bioavailability were tested in Japanese quail fed lettuce and spinach. Four groups of birds received 10% of their diets as lettuce or spinach leaves intrinsically labeled with {sup 109}Cd and containing low or high intrinsic Zn. Two other groups were fed control diets containing {sup 109}Cd as CdSO{sub 4} and low or high Zn as ZnCO{sub 3}. Cadmium concentrations in diets ranged from 0.857 to 1.05 {mu}g/g dry wt. Zinc concentrations in low-Zn diets ranged from 21.2 to 22.8, and in high-Zn diets from 56.0 to 63.3 {mu}g/g dry wt. Increased lettuce and spinach Zn decreased plant Cd retention in kidney, liver, and jejunum-ileum of Japanese quail. Spinach Cd was less absorbed than lettuce Cd at both Zn levels. Inorganic Zn produced a lesser decrease in Cd retention in kidney, liver, and jejunum-ileum than did plant Zn. The authors conclude that (1) crops that transport Zn and Cd readily into edible tissues show lower Cd bioavailability when grown in Zn-Cd contaminated environments than in Cd-only polluted sites, (2) plant species differ in Cd bioavailability for identical concentrations of Zn and Cd in edible tissues, and (3) toxicological studies with animals exposed to Cd salts and Zn supplements do not assess Cd bioavailability of Zn-Cd contaminated crops.

McKenna, I.M.; Keach, R.M. Jr; Williams, F.M. (Pennsylvania State Univ., University Park (United States)); Chaney, R.L. (Pennsylvania State Univ., University Park (United States) Dept. of Agriculture, Beltsville, MD (United States)); Tao, Shyy-Hwa (Food and Drug Administration, Washington, DC (United States))



[Conservation priorities for plant species of forest-meadow ecotone in Sanjiangyuan Nature Reserve].  


Based on field survey, information collection and experts consultation, the quantitative grading index system and assessment standards for preference conservation of rare and endangered plant species of forest-meadow ecotone in Sanjiangyuan Nature Reserve were established by using the methods and principles of systematical analysis. The quantitative grading index system included endangered coefficient, genetic coefficient, and useful value coefficient. In addition, 10 indicators used to evaluate endangered grading and conservation priorities sequenc, were also included in 3 subsystems respectively. Furthermore, the weights of 3 subsystem and 10 indicators were given through experts consultation and analytic hierarchy process. Endangered coefficient and conservation priorities coefficient, which respectively described the endangered grading, and preferential conservation of plant species were calculated by mathematic models and computer program. Contrasting to the standards of endangered grading and conservation priorities for plant species, we quantitatively evaluated the status of endangered and conservation priorities of plant species. The results showed that the number of endangered species was 4, vulnerable species 68, lower risk species 179, safety species 695; the number of the first class species was 8, the second class species 78, the third class species 164, and the delayed conservation species 696. Finally, we discussed the problems of indicator system and its weight, the relationship between endangered grading and conservation priorities sequence, and the spatial scale problem of plant species assessment. PMID:15573978

He, Youjun; Cui, Guofa; Feng, Zongwei; Zheng, Jie; Dong, Jiansheng; Li, Yongbo



Isolation and characterization of a Na+/H+ antiporter gene from the halophyte Atriplex gmelini.  


With a homologous gene region we successfully isolated a Na+/H+ antiporter gene from a halophytic plant, Atriplex gmelini, and named it AgNHX1. The isolated cDNA is 2607 bp in length and contains one open reading frame, which comprises 555 amino acid residues with a predicted molecular mass of 61.9 kDa. The amino acid sequence of the AgNHX1 gene showed more than 75% identity with those of the previously isolated NHX1 genes from glycophytes, Arabidopsis thaliana and Oryza sativa. The migration pattern of AgNHX1 was shown to correlate with H+-pyrophosphatase and not with P-type H+-ATPase, suggesting the localization of AgNHX1 in a vacuolar membrane. Induction of the AgNHX1 gene was observed by salt stress at both mRNA and protein levels. The expression of the AgNHX1 gene in the yeast mutant, which lacks the vacuolar-type Na+/H+ antiporter gene (NHX1) and has poor viability under the high-salt conditions, showed partial complementation of the NHX1 functions. These results suggest the important role of the AgNHX1 products for salt tolerance. PMID:11437248

Hamada, A; Shono, M; Xia, T; Ohta, M; Hayashi, Y; Tanaka, A; Hayakawa, T



Aquatic plant community invasibility and scale-dependent patterns in native and invasive species richness.  


Invasive species richness often is negatively correlated with native species richness at the small spatial scale of sampling plots, but positively correlated in larger areas. The pattern at small scales has been interpreted as evidence that native plants can competitively exclude invasive species. Large-scale patterns have been understood to result from environmental heterogeneity, among other causes. We investigated species richness patterns among submerged and floating-leaved aquatic plants (87 native species and eight invasives) in 103 temperate lakes in Connecticut (northeastern USA) and found neither a consistently negative relationship at small (3-m2) scales, nor a positive relationship at large scales. Native species richness at sampling locations was uncorrelated with invasive species richness in 37 of the 60 lakes where invasive plants occurred; richness was negatively correlated in 16 lakes and positively correlated in seven. No correlation between native and invasive species richness was found at larger spatial scales (whole lakes and counties). Increases in richness with area were uncorrelated with abiotic heterogeneity. Logistic regression showed that the probability of occurrence of five invasive species increased in sampling locations (3 m2, n = 2980 samples) where native plants occurred, indicating that native plant species richness provided no resistance against invasion. However, the probability of three invasive species' occurrence declined as native plant density increased, indicating that density, if not species richness, provided some resistance with these species. Density had no effect on occurrence of three other invasive species. Based on these results, native species may resist invasion at small spatial scales only in communities where density is high (i.e., in communities where competition among individuals contributes to community structure). Most hydrophyte communities, however, appear to be maintained in a nonequilibrial condition by stress and/or disturbance. Therefore, most aquatic plant communities in temperate lakes are likely to be vulnerable to invasion. PMID:18229847

Capers, Robert S; Selsky, Roslyn; Bugbee, Gregory J; White, Jason C



The effects of Phoma macrostoma on nontarget plant and target weed species  

Microsoft Academic Search

Phoma macrostoma 94-44B was evaluated against 94 plant species in 34 botanical families, of economically important agricultural, horticultural and ornamental species, as well as target and nontarget weeds. Fifty-seven species from 28 families were found to be resistant to P. macrostoma, while 38 species from 12 families, six of which also contained resistant species, were found to be susceptible. Those

K. L. Bailey; W. M. Pitt; S. Falk; J. Derby



Development of specific rhizosphere bacterial communities in relation to plant species, nutrition and soil type  

Microsoft Academic Search

Rhizosphere microbial communities are important for plant nutrition and plant health. Using the culture-independent method of PCR-DGGE of 16S rDNA for community analyses, we conducted several experiments to investigate the importance of pH, soil type, soil amendment, nutritional status of the plant, plant species and plant age on the structure of the bacterial community in the rhizosphere. At the same

Petra Marschner; David Crowley; Ching Hong Yang



Determination of Effects of Designated Pollutants on Plant Species.  

National Technical Information Service (NTIS)

The phytotoxic responses of selected plants to missile exhaust products were studied. The plants included but were not limited to ornamental, vegetable, and field crops found in the vicinity of Vandenberg Air Force Base and were grown in greenhouses equip...

A. L. Granett O. C. Taylor



The influence of prey capture on photosynthetic rate in two aquatic carnivorous plant species  

Microsoft Academic Search

Photosynthetic (PN) and dark respiration rate (RD) were measured in two species of aquatic carnivorous plants, Aldrovanda vesiculosa and Utricularia australis, growing with or without prey in an outdoor growth experiment. After 7–14 days, the positive growth effect of feeding on prey (apical growth rate, plant size, branching) was evident in both species. Tissue N content in young leaf whorls

Lubomír Adamec



Widespread Paleopolyploidy in Model Plant Species Inferred from Age Distributions of Duplicate Genes  

Microsoft Academic Search

It is often anticipated that many of today's diploid plant species are in fact paleopolyploids. Given that an ancient large-scale duplication will result in an excess of relatively old duplicated genes with similar ages, we analyzed the timing of duplication of pairs of paralogous genes in 14 model plant species. Using EST contigs (unigenes), we identified pairs of paralogous genes

Guillaume Blanca; Kenneth H. Wolfe



Microsoft Academic Search

Of the 425 plant taxa observed within Schwamberger Preserve, 8 taxa (1.88%) are listed on Ohio's legal list of endangered species prepared by the Ohio Depart- ment of Natural Resources. Eight taxa (1.88%) are on the legal list of threatened species. The location of the 5 plant communities within the preserve is governed by variation of the depth of the




Complementarity in mineral nitrogen use among dominant plant species in a subalpine community  

Microsoft Academic Search

The underlying mechanisms that enable plant species to coexist are poorly understood. Complementarity in resource use is among the major mechanisms proposed that could favor species coexistence but is insufficiently documented. In alpine soil, low temperatures are a major constraint for the supply of plant nitrogen. We carried out 15N labeling of soil mineral N to determine to what extent

A. Pornon; N. Escaravage; T. Lamaze



Pollination of two species of Ferocactus: interactions between cactus-specialist bees and their host plants  

Microsoft Academic Search

Summary 1. Resolving the controversy over the prevalence of generalization in plant-pollinator interactions requires field studies characterizing the pollination effectiveness of all a plant's floral visitors. Herein, the pollination effectiveness of all visitors to two species of barrel cactus ( Ferocactus ) was quantified. 2. Flowers of both species were pollinated almost exclusively by cactus-specialist bees: 99% ( F. cylindraceus




Plant Species Diversity and Distribution in Pastures of the Northeastern USA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Grazed pastures in the northeastern United contain far more than planted forage species. These species may contribute to forage production, but they may also detract from forage production or palatability. As the first step toward identifying the role of plant diversity in forage systems, we collect...


Reactions of various plant species to inoculation with potato virus S  

Microsoft Academic Search

In total 98 plant species belonging to 15 families were tested on their possible value as indicator hosts for potato virus S. Plants were sap-inoculated with six virus isolates respectively. In only three families (Amaranthaceae, Chenopodiaceae and Solanaceae) suspectible species were found. The susceptible Chenopodiaceae reacted with local lesions. Seven of those Chenopodiaceae were not mentioned before as local lesion

J. A. De Bokx



Phytotoxic Ozone Effect on Selected Plant Species in a Standardized Experimental Design  

Microsoft Academic Search

The most phytotoxic atmospheric pollutant is ozone which represents a stress factor for forest species and for the growth and the production of many plant species used in agriculture, resulting in great economic loss. Experimental protocols for passive and active biomonitoring studies to assess plant injury induced by ozone have been adopted by the United Nations\\/Economic Commission for Europe (UN\\/ECE)

Manes Fausto; Capogna Francesca; Giannini Antonietta; Silli Valerio


Loss of native aquatic plant species in a community dominated by Eurasian watermilfoil  

Microsoft Academic Search

Ecological evaluation of the impact of an exotic species upon native plant species is frequently a combination of historical data prior to introduction and after full establishment with little observation in between. The introduction of Myriophyllum spicatum L. (Eurasian watermilfoil) into Lake George, New York, U.S.A. was first noted in 1985. In 1987, a few newly established plants were allowed

Charles W. Boylen; Lawrence W. Eichler; John D. Madsen



Relative allelopathic potential of invasive plant species in a young disturbed woodland  

Microsoft Academic Search

Invasive plant species are often more successful within introduced areas when compared to their natural ranges. Allelopathy has been suggested as a potential mechanism for this success because invasive plants frequently establish monocultures and may produce allelochemicals evolutionarily novel to the recipient community. However, species are typically tested in isolation making the relative strength of allelopathy difficult to assess. We

Nikki L. Pisula; Scott J. Meiners



Accounting for diversity of plant species in watershed ecosystems by integrating field study and remote sensing  

Microsoft Academic Search

Diversity of plant species in watershed ecosystems was evaluated by Biodiversity Probability Index (BPI). BPI was calculated from HSI (Habitat Suitability Index) of all plant species and land area of ecotope, which was acquired by some geo-information, including vegetation data from field survey and land cover data from the satellite images of Landsat-TM. High BPI zone are concentrated on the

S. Ishiwatari; F. Hirota; H. Taguchi; H. Fukui; A. Makino



Strategies of heavy metal uptake by three plant species growing near a metal smelter  

Microsoft Academic Search

Some higher plant species have developed heavy metal tolerance strategies which enable them to survive and reproduce in highly metal-contaminated soils. We have investigated such heavy metal uptake and accumulation strategies of two absolute metallophyte species (Armeria maritima ssp. halleri and Cardaminopsis halleri) and one pseudometallophyte (Agrostis tenuis) growing near a former metal smelter. Samples of plant parts and soil

H Dahmani-Muller; F van Oort; B Gélie; M Balabane



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



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



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


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



Plant Species Richness and Nitrogen Deposition can Alter Microbial Assimilation of New Photosynthate  

NASA Astrophysics Data System (ADS)

Microbial assimilation of recent photosynthate was analyzed in a 6-year-long field experiment to determine how plant species richness impacts microbial metabolism of new photosynthate, and how this may be modified by atmospheric N deposition. Our study was conducted at the BioCON (Biodiversity, CO2, and Nitrogen) FACE (Free-Air Carbon dioxide Enrichment) experiment located at the Cedar Creek Natural History area in Minnesota, USA. In this experiment, plant species richness, atmospheric N deposition, and atmospheric CO2 concentration were manipulated in concert. The depleted ?13C of fumigation CO2 enabled us to investigate the effect of plant species richness and atmospheric N deposition on the metabolism of soil microbial communities in the elevated CO2 treatment. We determined the ?13C of bacterial, actinobacterial, and fungal phospholipid fatty acids (PLFA). In the elevated CO2 conditions of this study, the ?13C of bacterial PLFAs (i15:0, i16:0, 16:1?7c, 16:1?9c, 10Me16:0, and 10Me18:0) and the fungal PLFA 18:1?9c was significantly lower in species-rich plant communities than in species-poor plant communities, indicating that microbial incorporation of new C increased with plant species richness. Despite an increase in plant production, total PLFA decreased under N deposition by 27%. Moreover, N deposition also decreased fungal relative abundance in species-rich plant communities. In our study, plant species richness directly increased microbial incorporation of new photosynthate, providing a mechanistic link between greater plant detritus production in species-rich plant communities and larger and more active soil microbial community.

Chung, H.; Zak, D.; Reich, P.



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



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



Assessing Vulnerability to Invasion by Nonnative Plant Species at Multiple Spatial Scales  

Microsoft Academic Search

Basic information on where nonnative plant species have successfully invaded is lacking. We assessed the vulnerability of\\u000a 22 vegetation types (25 sets of four plots in nine study areas) to nonnative plant invasions in the north–central United States.\\u000a In general, habitats with high native species richness were more heavily invaded than species-poor habitats, low-elevation\\u000a areas were more invaded than high-elevation




Effect of within-species plant genotype mixing on habitat preference of a polyphagous insect predator  

Microsoft Academic Search

The effects of within-species plant genotype mixing on the habitat preference of a polyphagous ladybird were studied. Plant\\u000a species diversity is often claimed to positively affect habitat preferences of insect predators, but the effects of within-species\\u000a genotype diversity have not been extensively studied. In a field experiment with different barley (Hordeum vulgare) genotypes in mixed and pure stands, adult seven-spot

Velemir Ninkovic; Sate Al Abassi; Elham Ahmed; Robert Glinwood; Jan Pettersson



Impact of three aquatic invasive species on native plants and macroinvertebrates in temperate ponds  

Microsoft Academic Search

Biological plant invasions pose a serious threat to native biodiversity and have received much attention, especially in terrestrial\\u000a habitats. In freshwater ecosystems impacts of invasive plant species are less studied. We hypothesized an impact on organisms\\u000a from the water column and from the sediment. We then assessed the impact of three aquatic invasive species on the plants and\\u000a macroinvertebrates: Hydrocotyle

Iris Stiers; Nicolas Crohain; Guy Josens; Ludwig Triest


Emission of isoprene from common Indian plant species and its implications for regional air quality  

Microsoft Academic Search

Isoprene is most dominant volatile organic compounds (VOC) emitted by many plants. In this study 40 common Indian plant species\\u000a were examined for isoprene emission using dynamic flow through enclosure chamber technique. Isoprene emission rates of plants\\u000a species were found to vary from undetectable to 69.5 ?g g?1 h?1 (Madhuca latifolia). Besides, an attempt has been made to evaluate suitability of

Rashmi Singh; Abhai Pratap Singh; M. P. Singh; Animesh Kumar; C. K. Varshney



Chemical and environmental manipulation of ornamental Acacia Mill. species for pot plant production  

Microsoft Academic Search

Chemical and environmental control of vegetative growth and flowering were investigated in ornamental Acacia species for pot plant production. High night temperature (20 °C\\/25 °C day\\/night vs. 25 °C\\/20 °C day\\/night) was ineffective in reducing height or width, but paclobutrazol (PBZ) controlled plant size of most species. Neither pruning nor 6-benzylamino purine (BAP) were effective in stimulating branching. Plants of

M. A. Parletta; M. Sedgley



Links between plant litter chemistry, species diversity, and below-ground ecosystem function  

PubMed Central

Decomposition is a critical source of plant nutrients, and drives the largest flux of terrestrial C to the atmosphere. Decomposing soil organic matter typically contains litter from multiple plant species, yet we lack a mechanistic understanding of how species diversity influences decomposition processes. Here, we show that soil C and N cycling during decomposition are controlled by the composition and diversity of chemical compounds within plant litter mixtures, rather than by simple metrics of plant species diversity. We amended native soils with litter mixtures containing up to 4 alpine plant species, and we used 9 litter chemical traits to evaluate the chemical composition (i.e., the identity and quantity of compounds) and chemical diversity of the litter mixtures. The chemical composition of the litter mixtures was the strongest predictor of soil respiration, net N mineralization, and microbial biomass N. Soil respiration and net N mineralization rates were also significantly correlated with the chemical diversity of the litter mixtures. In contrast, soil C and N cycling rates were poorly correlated with plant species richness, and there was no relationship between species richness and the chemical diversity of the litter mixtures. These results indicate that the composition and diversity of chemical compounds in litter are potentially important functional traits affecting decomposition, and simple metrics like plant species richness may fail to capture variation in these traits. Litter chemical traits therefore provide a mechanistic link between organisms, species diversity, and key components of below-ground ecosystem function.

Meier, Courtney L.; Bowman, William D.



Species richness of vascular plants, bryophytes, and lichens along an altitudinal gradient in western Norway  

NASA Astrophysics Data System (ADS)

Species richness patterns of ground-dwelling vascular plants, bryophytes, and lichens were compared along an altitudinal gradient (310-1135 m a.s.l.), in western Norway. Total species richness peaked at intermediate altitudes, vascular plant species richness peaked immediately above the forest limit (at 600-700 m a.s.l.), bryophyte species richness had no statistically significant trend, whereas lichen richness increased from the lowest point and up to the forest limit, with no trend above. It is proposed that the pattern in vascular plant species richness is enhanced by an ecotone effect. Bryophyte species richness responds to local scale factors whereas the lichen species richness may be responding to the shading from the forest trees.

Grytnes, John Arvid; Heegaard, Einar; Ihlen, Per G.



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


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




Microsoft Academic Search

Biological invasions can have strong ecological effects on native communities by altering ecosystem functions, species interactions, and community composition. Even though these ecological effects frequently impact the population dynamics and fitness of native species, the evolutionary consequences of biological invasions have received relatively little attention. Here, I show that invasions impose novel selective pressures on a native plant species. By

Jennifer A. Lau



Plant uptake and determination of arsenic species in soil solution under flooded conditions  

Microsoft Academic Search

Previous studies have not identified the different As species present in soil systems and determined if effective differences exist between As species with respect to plant parameters such as growth rate and As uptake. This study determined the species and concentrations of As present in soil solution of flooded soils and correlated them to As concentration, P concentration, an growth

B. M. Onken; L. R. Hossner



Students’ Perception of Plant and Animal Species: A Case Study From Rural Argentina  

Microsoft Academic Search

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 local species and describe their

Juliana Nates; Claudia Campos; Petra Lindemann-Matthies



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



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

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



Searching the World's Herbaria: A System for Visual Identification of Plant Species  

Microsoft Academic Search

We describe a working computer vision system that aids in the identiflcation of plant species. A user photographs an isolated leaf on a blank background, and the system extracts the leaf shape and matches it to the shape of leaves of known species. In a few seconds, the sys- tem displays the top matching species, along with textual descriptions and

Peter N. Belhumeur; Daozheng Chen; Steven Feiner; David W. Jacobs; W. John Kress; Haibin Ling; Ida Lopez; Ravi Ramamoorthi; Sameer Sheorey; Sean White; Ling Zhang



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



Influence of Citric Acid Amendments on the Availability of Weathered PCBs to Plant and Earthworm Species  

Microsoft Academic Search

A series of small and large pot trials were conducted to assess the phytoextraction potential of several plant species for weathered polychlorinated biphenyls (PCBs) in soil (105 ? g\\/g Arochlor 1268). In addition, the effect of citric acid on PCB bioavailability to both plants and earthworms was assessed. Under small pot conditions (one plant, 400 g soil), three cucurbits (Cucurbita

Jason C. White; Zakia D. Parrish; Mehmet Isleyen; Martin P. N. Gent; William Iannucci-Berger; Brian D. Eitzer; Jason W. Kelsey; Maryjane Incorvia Mattina



78 FR 59269 - Endangered and Threatened Wildlife and Plants; Endangered Species Status for the Fluted...  

Federal Register 2010, 2011, 2012, 2013

...Threatened Wildlife and Plants; Endangered Species...maturity, when energy is being diverted...of reproductive cells or gametes) of...Threatened Wildlife and Plants. Under section...nutrients, energy inputs, and the Federal Energy Regulatory Commission...THREATENED WILDLIFE AND PLANTS 0 1. The...



Moose as a vector for non-indigenous plant species in Alaska  

Technology Transfer Automated Retrieval System (TEKTRAN)

White sweetclover and narrowleaf hawksbeard are non-indigenous invasive plant species in Alaska that are rapidly spreading, including into areas that are otherwise free of non-indigenous plants. There has been concern that native moose could be dispersing viable seed from these plants after ingestio...


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




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


Predicting global change impacts on plant species’ distributions: Future challenges  

Microsoft Academic Search

Given the rate of projected environmental change for the 21st century, urgent adaptation and mitigation measures are required to slow down the on-going erosion of biodiversity. Even though increasing evidence shows that recent human-induced environmental changes have already triggered species’ range shifts, changes in phenology and species’ extinctions, accurate projections of species’ responses to future environmental changes are more difficult

Wilfried Thuiller; Cécile Albert; Miguel B. Araújo; Pam M. Berry; Mar Cabeza; Antoine Guisan; Thomas Hickler; Guy F. Midgley; James Paterson; Frank M. Schurr; Martin T. Sykes; Niklaus E. Zimmermann



Rhizobia species : A Boon for “Plant Genetic Engineering”  

Microsoft Academic Search

Since past three decades new discoveries in plant genetic engineering have shown remarkable potentials for crop improvement.\\u000a Agrobacterium Ti plasmid based DNA transfer is no longer the only efficient way of introducing agronomically important genes into plants.\\u000a Recent studies have explored a novel plant genetic engineering tool, Rhizobia sp., as an alternative to Agrobacterium, thereby expanding the choice of bacterial

Urmi Patel; Sarika Sinha


Arbuscular mycorrhizal fungi reduce the differences in competitiveness between dominant and subordinate plant species.  


In grassland communities, plants can be classified as dominants or subordinates according to their relative abundances, but the factors controlling such distributions remain unclear. Here, we test whether the presence of the arbuscular mycorrhizal (AM) fungus Glomus intraradices affects the competitiveness of two dominant (Taraxacum officinale and Agrostis capillaris) and two subordinate species (Prunella vulgaris and Achillea millefolium). Plants were grown in pots in the presence or absence of the fungus, in monoculture and in mixtures of both species groups with two and four species. In the absence of G. intraradices, dominants were clearly more competitive than subordinates. In inoculated pots, the fungus acted towards the parasitic end of the mutualism-parasitism continuum and had an overall negative effect on the growth of the plant species. However, the negative effects of the AM fungus were more pronounced on dominant species reducing the differences in competitiveness between dominant and subordinate species. The effects of G. intraradices varied with species composition highlighting the importance of plant community to mediate the effects of AM fungi. Dominant species were negatively affected from the AM fungus in mixtures, while subordinates grew identically with and without the fungus. Therefore, our findings predict that the plant dominance hierarchy may flatten out when dominant species are more reduced than subordinate species in an unfavourable AM fungal relationship (parasitism). PMID:23064770

Mariotte, Pierre; Meugnier, Claire; Johnson, David; Thébault, Aurélie; Spiegelberger, Thomas; Buttler, Alexandre



Species-specificity of nurse plants for the establishment, survivorship, and growth of a columnar cactus.  


• Premise of the study: Seedling establishment and early survivorship are crucial steps for the regeneration of plant populations because both have long-lasting effects on plant population dynamics. For species recruiting through facilitation, species-specific facilitative effects might affect early fitness, an overlooked aspect in studies of facilitation considering groups of nurse species. • Methods: We experimentally evaluated the roles of 10 nurse species and open space on the early performance of the columnar cactus Neobuxbaumia mezcalaensis. We measured establishment, survivorship, and growth of individuals over 3 years. Moreover, to study an extended period of the ontogeny of the interaction between this cactus and its nurse plants, we also monitored survivorship and growth rates of individuals between 3 to 12 cm tall during a 3-year period. • Key results: Neobuxbaumia mezcalaensis performance varied significantly among nurse species, and only six yielded positive effects on early fitness. Densely canopied plants were the best nurses for this cactus. However, even among densely canopied species, some produced negative effects on the early fitness of N. mezcalaensis, indicating that similar nurse plants may elicit either facilitative or interference effects on beneficiary species. • Conclusions: Our results emphasize the importance of species-specific facilitative interactions in the crucial early stages in the life cycle of N. mezcalaensis and how different nurse species modify the effect of seed-rain and contribute significantly to the population dynamics of the species. PMID:21616881

Landero, Juan Pablo Castillo; Valiente-Banuet, Alfonso



Effects of invasive species on plant communities: an example using submersed aquatic plants at the regional scale  

Microsoft Academic Search

Submersed aquatic plants have a key role in maintaining functioning aquatic ecosystems through their effects on the hydrological\\u000a regime, sedimentation, nutrient cycling and habitat of associated fauna. Modifications of aquatic plant communities, for example\\u000a through the introduction of invasive species, can alter these functions. In the Sacramento-San Joaquin River Delta, California,\\u000a a major invasive submersed plant, Brazilian waterweed Egeria densa,

Maria J. SantosLars; Lars W. Anderson; Susan L. Ustin



Effect of Plant Species and Environmental Conditions on Ice Nucleation Activity of Pseudomonas syringae on Leaves  

PubMed Central

Selected plant species and environmental conditions were investigated for their influences on expression of ice nucleation activity by 15 Pseudomonas syringae strains grown on plants in constant-temperature growth chamber studies. Ice nucleation frequencies (INFs), the fraction of cells that expressed ice nucleation at ?5 or ?9°C, of individual strains varied greatly, both on plants and in culture. This suggests that the probability of frost injury, which is proportional to the number of ice nuclei on leaf surfaces, is strongly determined by the particular bacterial strains that are present on a leaf surface. The INFs of strains were generally higher when they were grown on plants than when they were grown in culture. In addition, INFs in culture did not correlate closely with INFs on plants, suggesting that frost injury prediction should be based on INF measurements of cells grown on plants rather than in culture. The relative INFs of individual strains varied with plant host and environment. However, none of seven plant species tested optimized the INFs of all 15 strains. Similarly, incubation for 48 h at near 100% relative humidity with short photoperiods did not always decrease the INF when compared with a 72 h, 40% relative humidity, long-photoperiod incubation. Pathogenic strains on susceptible hosts were not associated with higher or lower INFs relative to their INFs on nonsusceptible plant species. The ice nucleation activity of individual bacterial strains on plants therefore appears to be controlled by complex and interacting factors such as strain genotype, environment, and host plant species.

O'Brien, R. Douglas; Lindow, Steven E.



GLM versus CCA spatial modeling of plant species distribution  

Microsoft Academic Search

Despite the variety of statistical methods available for static modeling of plant distribution, few studies directly compare methods on a common data set. In this paper, the predictive power of Generalized Linear Models (GLM) versus Canonical Correspondence Analysis (CCA) models of plant distribution in the Spring Mountains of Nevada, USA, are compared. Results show that GLM models give better predictions

Antoine Guisan; Stuart B. Weiss; Andrew D. Weiss



Plant Growth and Phosphorus Uptake of Three Riparian Grass Species  

Technology Transfer Automated Retrieval System (TEKTRAN)

Riparian buffers can significantly reduce sediment-bound phosphorus (P) entering surface water, but control of dissolved P inputs is more challenging. Because plant roots remove P from soil solution, it follows that plant uptake will reduce dissolved P losses. We evaluated P uptake of smooth bromegr...


Sodium instead of potassium and chloride is an important macronutrient to improve leaf succulence and shoot development for halophyte Sesuvium portulacastrum.  


Soil salinity is contributed largely by NaCl but some halophytes such as Sesuvium portulacastrum have evolved to adapt salinity environment and demonstrate optimal development under moderate salinity. To elucidate the detail mechanisms of the great salt tolerance and determine the respective contributions of Na(+), K(+) and Cl(-) on the development of S. portulacastrum, morphological and physiological analysis were performed using plants supplied with 200 mM of different ions including cations (Na(+), K(+), Li(+)) and anions (Cl(-), NO(3)(-), Ac(-)) respectively. The results revealed that the salt-treated plants accumulated large amounts of sodium in both leaf and stem. There was a greater shoot growth in presence of external Na(+) compared to K(+) and Cl(-). Na(+) was found more effective than K(+) and Cl(-) in cell expansion, leaf succulence, and shoot development. Flame emission and X-Ray microanalysis revealed the relative Na(+) content was much higher than K(+) and Cl(-) in both leaf and stem of well developed S. portulacastrum, leading to a higher Na(+)/K(+) ratio. The effects of different ions on the development of S. portulacastrum were listed as the following: Na(+) > NO(3)(-) > CK > Cl(-) > K(+) > Ac(-) > Li(+). These results demonstrated NaCl toxicity is attributable largely to the effect of Cl(-) but rarely to Na(+), and thus sodium is concluded as a more important macronutrient than potassium and chloride for improving leaf succulence and shoot development of halophyte S. portulacastrum. PMID:22153240

Wang, Dongyang; Wang, Haiyan; Han, Bing; Wang, Bin; Guo, Anping; Zheng, Dong; Liu, Chongjing; Chang, Lili; Peng, Ming; Wang, Xuchu



Genetic diversity in widespread species is not congruent with species richness in alpine plant communities.  


The Convention on Biological Diversity (CBD) aims at the conservation of all three levels of biodiversity, that is, ecosystems, species and genes. Genetic diversity represents evolutionary potential and is important for ecosystem functioning. Unfortunately, genetic diversity in natural populations is hardly considered in conservation strategies because it is difficult to measure and has been hypothesised to co-vary with species richness. This means that species richness is taken as a surrogate of genetic diversity in conservation planning, though their relationship has not been properly evaluated. We tested whether the genetic and species levels of biodiversity co-vary, using a large-scale and multi-species approach. We chose the high-mountain flora of the Alps and the Carpathians as study systems and demonstrate that species richness and genetic diversity are not correlated. Species richness thus cannot act as a surrogate for genetic diversity. Our results have important consequences for implementing the CBD when designing conservation strategies. PMID:23006492

Taberlet, Pierre; Zimmermann, Niklaus E; Englisch, Thorsten; Tribsch, Andreas; Holderegger, Rolf; Alvarez, Nadir; Niklfeld, Harald; Coldea, Gheorghe; Mirek, Zbigniew; Moilanen, Atte; Ahlmer, Wolfgang; Marsan, Paolo Ajmone; Bona, Enzo; Bovio, Maurizio; Choler, Philippe; Cie?lak, El?bieta; Colli, Licia; Cristea, Vasile; Dalmas, Jean-Pierre; Frajman, Božo; Garraud, Luc; Gaudeul, Myriam; Gielly, Ludovic; Gutermann, Walter; Jogan, Nejc; Kagalo, Alexander A; Korbecka, Gra?yna; Küpfer, Philippe; Lequette, Benoît; Letz, Dominik Roman; Manel, Stéphanie; Mansion, Guilhem; Marhold, Karol; Martini, Fabrizio; Negrini, Riccardo; Niño, Fernando; Paun, Ovidiu; Pellecchia, Marco; Perico, Giovanni; Pi?ko?-Mirkowa, Halina; Prosser, Filippo; Pu?ca?, Mihai; Ronikier, Micha?; Scheuerer, Martin; Schneeweiss, Gerald M; Schönswetter, Peter; Schratt-Ehrendorfer, Luise; Schüpfer, Fanny; Selvaggi, Alberto; Steinmann, Katharina; Thiel-Egenter, Conny; van Loo, Marcela; Winkler, Manuela; Wohlgemuth, Thomas; Wraber, Tone; Gugerli, Felix; Vellend, Mark



Nurse-plant and mulching effects on three conifer species in a Mexican temperate forest  

Microsoft Academic Search

Nurse-plant effects have been used as an effective reforestation and restoration strategy, and mulching has also effectively ameliorated soil-adverse conditions. However, use of nurse plants is limited by the presence of suitable nurse species before trees are planted, and use of mulching depends on availability of appropriate materials. The effects of Lupinus elegans as a nurse plant and pine-bark mulch

Arnulfo Blanco-García; Cuauhtémoc Sáenz-Romero; Carlos Martorell; Pedro Alvarado-Sosa; Roberto Lindig-Cisneros



Deconstructing responses of dragonfly species richness to area, nutrients, water plant diversity and forestry.  


Understanding large-scale variation in species richness in relation to area, energy, habitat heterogeneity and anthropogenic disturbance has been a major task in ecology. Ultimately, variation in species richness results from variation in individual species occupancies. We studied whether the individual species occupancy patterns are determined by the same candidate factors as total species richness. We sampled 26 boreal forest ponds for dragonflies (Odonata) and studied the effects of shoreline length, water vascular plant species density (WVPSD), availability of nutrients, intensity of forestry, amount of Sphagnum peat cover and pH on dragonfly species richness and individual dragonfly species. WVPSD and pH had a strong positive effect on species richness. Removal of six dragonfly species experiencing strongest responses to WVPSD cancelled the relationship between species richness and WVPSD. By contrast, removal of nine least observed species did not affect the relationship between WVPSD and species richness. Thus, our results showed that relatively common species responding strongly to WVPSD shaped the observed species richness pattern whereas the effect of least observed, often rare, species was negligible. Also, our results support the view that, despite of the great impact of energy on species richness at large spatial scales, habitat heterogeneity can still have an effect on species richness in smaller scales, even overriding the effects of area. PMID:21113624

Honkanen, Merja; Sorjanen, Aili-Maria; Mönkkönen, Mikko



Pseudonocardia nantongensis sp. nov., a novel endophytic actinomycete isolated from the coastal halophyte Tamarix chinensis Lour.  


A novel isolate, designated strain KLBMP 1282(T) was isolated from the surface-sterilized leaves of a coastal halophyte Tamarix chinensis Lour., collected from Nantong, Jiangsu Province, east of China. Phylogenetic analysis based on 16S rRNA gene sequences revealed that this strain belongs to the genus Pseudonocardia, being most closely related to Pseudonocardia kongjuensis LM 157(T) (98.33 %), Pseudonocardia autotrophica IMSNU 20050(T) (97.77 %), Pseudonocardia endophytica YIM 56035(T) (97.63 %), Pseudonocardia ammonioxydans H9 (T) (97.62 %) and Pseudonocardia compacta IMSNU 20111(T) (97.56 %); similarity to other type strains of the genus Pseudonocardia was <97.5 %. Chemotaxonomic data confirmed the affiliation of strain KLBMP 1282(T) to the genus Pseudonocardia. Strain KLBMP 1282(T) contained MK-8(H(4)) as the predominant ubiquinone and iso-C(16:0) as the major fatty acid. The polar lipids detected in strain KLBMP 1282(T) were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides, one unknown phospholipid and four unknown glycolipids. The DNA G + C content of strain KLBMP 1282(T) was 73.1 mol %. The results of DNA-DNA hybridizations and the phylogenetic analysis, together with the phenotypic and biochemical tests, allowed the differentiation of strain KLBMP 1282(T) from strains of other recognized Pseudonocardia species. Therefore, strain KLBMP 1282(T) represents a novel species of the genus Pseudonocardia, for which the name Pseudonocardia nantongensis sp. nov. is proposed. The type strain is KLBMP 1282(T) (=KCTC 29053(T) = NBRC 108677(T)). PMID:22733061

Xing, Ke; Qin, Sheng; Bian, Guang-Kai; Zhang, Yue-Ji; Zhang, Wen-Di; Dai, Chuan-Chao; Liu, Chang-Hong; Li, Wen-Jun; Jiang, Ji-Hong



Emission of volatile organic compounds (VOC) from tropical plant species in India.  


Foliar emission of volatile organic compounds (VOC) from common Indian plant species was measured. Dynamic flow enclosure technique was used and the gas samples were collected onto Tenax-GC/Carboseive cartridges. The Tenax-GC/Carboseive cartridges were attached to the thermal disorber sample injection system and the gas sample was analysed using gas chromatography (GC) with flame ionisation detection (FID). Fifty-one local plant species were screened, out of which 36 species were found to emit VOC (4 high emitter; 28 moderate emitter; and 4 low-emitter), while in the remaining 15 species no VOC emission was detected or the levels of emission were below detection limit (BDL). VOC emission was found to vary from one species to another. There was a marked seasonal and diurnal variation in VOC emission. The minimum and maximum VOC emission values were < 0.1 and 87 microgg(-1) dry leaf h(-1) in Ficus infectoria and Lantana camara respectively. Out of the 51 plant species studied, 13 species are reported here for the first time. Among the nine tree species (which were selected for detailed study), the highest average hourly emission (9.69+/-8.39 microgg(-1) dry leaf) was observed in Eucalyptus species and the minimum in Syzygium jambolanum (1.89+/-2.48 microgg(-1) dry leaf). An attempt has been made to compare VOC emission from different plant species between present study and the literature (tropical and other regions). PMID:15894050

Padhy, P K; Varshney, C K



Critical review on medicinally potent plant species: Gloriosa superba.  


Gloriosa superba L. is a perennial climber and is used as an ayurvedic medicinal herb to cure diseases in various parts of Africa and Southeast Asia. The plant was under threatened category due to its imprudent harvesting from wild as it is extensively used by medicinal industries for its colchicine content. It also faces a low seed set problem, but due to its industrial demand it is now under cultivation. The plant is used to cure arthritis, gout, rheumatism, inflammation, ulcers, bleeding piles, skin diseases, leprosy, impotency, snakebites, etc. Various compounds have been isolated from the plant parts mainly tubers and seeds, viz colchicine, colchicoside (its semi-synthetic derivative - thiocolchicoside), superbine, gloriosine, lumicolchicine, 3-demethyl-N-deformyl-N-deacetylcolchicine, 3-demethylcolchicine, N-formyl deacetylcolchicine. In the present review, we have summarized the information concerning the occurrence, botanical description, ethanopharmacology, medicinal uses, biological activities and toxicological studies on this plant. PMID:21059382

Jana, Sonali; Shekhawat, G S



Development of Biological Controls for Noxious Plant Species.  

National Technical Information Service (NTIS)

The proposed research on this contract consisted of the following objectives: (1) To discover and collect plant pathogens of selected weeds through field surveys in Florida; (2) determine the biological control ability of pathogens against their weed host...

R. Charudattan



Gene flow and local adaptation in two endemic plant species  

Microsoft Academic Search

In order to detect the evolutionary potential of two endangered species, Brassica insularis (Brassicaceae) and Centaurea corymbosa (Asteraceae), within and among-population genetic variation for both quantitative traits and allozymic markers was examined. Four populations of each species were studied, representing a large proportion of extant populations. High values of ?ST (0.213 and 0.364 for B. insularis and C. corymbosa respectively)

Christophe Petit; Hélène Fréville; Agnès Mignot; Bruno Colas; Miquel Riba; Eric Imbert; Sylvie Hurtrez-Boussés; Myriam Virevaire; Isabelle Olivieri



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



In search for key biogeochemical factors for the conservation of plant species of acidic nutrient-poor habitats: comparing growth sites of common and endangered species  

Microsoft Academic Search

Summary During the last century, many plant species typical of heathland and nutrient-poor acidic grasslands have become rare whereas others have remained common. Habitat restoration often fails to enhance the rare species, which may in part be caused by the failure to restore the biogeochemical conditions suited to these species. Many soil variables have been shown to affect plant fitness

D. Kleijn; R. M. Bekker; R. Bobbink; Graaf de M. C. C; J. G. M. Roelofs



Quantitative resistance traits and suitability of woody plant species for a polyphagous scarab, Popillia japonica Newman.  


The Japanese beetle, Popillia japonica Newman, has an unusually broad host range among deciduous woody plants, yet it feeds only sparingly, or not at all, on certain species in the field. We evaluated beetles' preference, survival over time and fecundity on eight woody plant species historically rated as susceptible or resistant and, after verifying those ratings, tested whether resistance is correlated with so-called quantitative defense traits including leaf toughness, low nutrient content (water, nitrogen, and sugars), and relatively high amounts of tannins or saponins, traditionally associated with such plants. We further tested whether species unsuitable for Japanese beetles are also rejected by fall webworms, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), the expected outcome if the aforementioned traits serve as broad-based defenses against generalists. Choice tests supported historical resistance ratings for the selected species: tuliptree, lilac, dogwood, and Bradford callery pear were rejected by Japanese beetles, whereas sassafras, cherry plum, Virginia creeper, and littleleaf linden were readily eaten. Rejected species also were unsuitable for survival over time, or egg-laying, indicating beetles' inability to overcome the resistance factors through habituation, compensatory feeding, or detoxification. None of the aforementioned leaf traits was consistently higher or lower in the resistant or susceptible plants, and plant species rejected by Japanese beetles often were not rejected by fall webworms. Specialized secondary chemistry, not quantitative defenses, likely determines the Japanese beetle's dietary range among deciduous woody plant species it may encounter. PMID:19161699

Keathley, Craig P; Potter, Daniel A



Assessment of bioaccumulation of heavy metals by different plant species grown on fly ash dump.  


A field experiment was conducted on a 10-hectare area on fly ash dump at Khaperkheda Thermal Power Plant, Nagpur, India, where different ecologically and economically important plant species were planted using bioremediation technology. The technology involves the use of organic amendment and selection of suitable plant species along with site-specific nitrogen-fixing strains of biofertilizers. The study was conducted to find out the metal accumulation potential of different plant species. The total heavy metal contents in fly ash were determined and their relative abundance was found in the order of Fe>Mn>Zn>Cu>Ni>Cr>Pb>Cd. Fly ash samples had acidic pH, low electrical conductivity, low level of organic carbon and trace amounts of N and P. Plantation of divergent species was done on fly ash dump using the bioremediation technique. After 3 years of plantation, luxuriant growth of these species was found covering almost the entire fly ash dump. The results of the metal analysis of these species indicated that iron accumulated to the greatest extent in vegetation followed by Mn, Ni, Zn, Cu, Cr and Pb. Cassia siamea was found to accumulate all metals at higher concentrations compared to other species. The experimental study revealed that C. siamea could be used as a hyper-accumulator plant for bioremediation of fly ash dump. PMID:19171381

Jambhulkar, Hemlata P; Juwarkar, Asha A



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))



Germination characteristics of six plant species growing on the Hanford Site. [Disturbed land revegetation feasibility studies  

SciTech Connect

Six plant species (Siberian and thickspike wheatgrass, cheatgrass, sand dropseed, Indian ricegrass, and Russian thistle) found on the Hanford Site were studied as part of an investigation into the revegetation of disturbed areas. Germination response to three environmental parameters (soil moisture, soil temperature, and planting depth) were measured. Results indicated that when a polyethylene glycol solution was used to control the osmotic potential of the imbibition media, no significant decrease in germination rate occurred down to -3.0 bars. However, below -7.0 bars all species experienced a decrease in germination. When germinated in soil, all species except Russian thistle exhibited a significant decrease in germination rate at -0.3 bars. Russian thistle was the only species tested that exhibited germination at a soil temperature of 1/sup 0/C. All species gave optimum germination at temperatures between 10 and 15/sup 0/C. Thickspike wheatgrass was the only species tested which was able to germinate and emerge from a planting depth of greater than 2 inches. If supplemental moisture is provided, a shallow planting would be advisable for those species tested. If not overcome by pretreatment prior to planting, seed dormancy may be a significant factor which will reduce the germination potential of some species tested.

Cox, G.R.; Kirkham, R.R.; Cline, J.F.



Phytoremediation of soil co-contaminated with heavy metals and TNT using four plant species.  


We investigated the germination, growth rates and uptake of contaminants of four plant species, barnyard grass (Echinochloa crusgalli), sunflower (Helianthus annuus), Indian mallow (Abutilon avicennae) and Indian jointvetch (Aeschynomene indica), grown in soil contaminated with cadmium (Cd), lead (Pb) and 2,4,6-trinitrotoluene (TNT). These contaminants are typically found at shooting ranges. Experiments were carried out over 180 days using both single plant cultures and cultures containing an equal mix of the 4 plant species. Germination rates differed among the species in single culture (92% for H. annuus, 84% for E. crusgalli, 48% for A. avicennae and 38% Ae. indica). In the 4-plant mix culture, < 20% of seeds germinated for all 4 species. E. crusgalli and H. annuus grew slightly faster in the four-plant mix culture than in single culture, whereas A. avicennae and Ae. indica grew much slower in the 4-plant mix culture. In both single and 4-plant mix cultures, Cd concentrations in the roots of A. avicennae and E. crusgalliwere high, and Pb concentrations were high in A. avicennae and H. annuus. Cd and Pb concentrations in shoots were low to negligible in both treatment cultures for all species, except E. crusgalli in the 4-plant mix culture. The concentrations of TNT and its metabolites, 2-amino-4,6-dinitrotoluene (2ADNT) and 4-amino-2,6-dinitrotoluene (4ADNT) were high in H. annuus, Ae. indica and A. avicennae. Total Cd removal from soil differed among species, with E. crusgalliremoving the most (50.1%) followed by H. annuus(41.3%), Ae. indica(41.1%) and A. avicennae(33.3%). The four-plant mix removed more Cd (25.8%) than a no-plant control (12.9%). Pb removal was negligible for all plant species. All plant species rapidly removed TNT and its metabolites, regardless of whether the culture was single or mixed. From in these results, we conclude that a phytoremediation for the removal of heavy metals and TNT from contaminated soils should use a single plant species rather than a mixture of several plants. PMID:17990167

Lee, Insook; Baek, Kyunghwa; Kim, Hyunhee; Kim, Sunghyun; Kim, Jaisoo; Kwon, Youngseok; Chang, Yoontoung; Bae, Bumhan



The new flora of northeastern USA: quantifying introduced plant species occupancy in forest ecosystems.  


Introduced plant species have significant negative impacts in many ecosystems and are found in many forests around the world. Some factors linked to the distribution of introduced species include fragmentation and disturbance, native species richness, and climatic and physical conditions of the landscape. However, there are few data sources that enable the assessment of introduced species occupancy in native plant communities over broad regions. Vegetation data from 1,302 forest inventory plots across 24 states in northeastern and mid-western USA were used to examine and compare the distribution of introduced species in relation to forest fragmentation across ecological provinces and forest types, and to examine correlations between native and introduced species richness. There were 305 introduced species recorded, and 66 % of all forested plots had at least one introduced species. Forest edge plots had higher constancy and occupancy of introduced species than intact forest plots, but the differences varied significantly among ecological provinces and, to a lesser degree, forest types. Weak but significant positive correlations between native and introduced species richness were observed most often in intact forests. Rosa multiflora was the most common introduced species recorded across the region, but Hieracium aurantiacum and Epipactus helleborine were dominant in some ecological provinces. Identifying regions and forest types with high and low constancies and occupation by introduced species can help target forest stands where management actions will be the most effective. Identifying seemingly benign introduced species that are more prevalent than realized will help focus attention on newly emerging invasives. PMID:22961328

Schulz, Bethany K; Gray, Andrew N



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




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...



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...


Development of Methods of Nitrogen Management for Woody Ornamental Species in Landscape Plantings.  

National Technical Information Service (NTIS)

The primary purpose of this experiment was to evaluate the effects of fertilizer nitrogen source on survival and growth of several woody ornamental species used in highway plantings. Even without nitrogen fertilization, very satisfactory growth occurred. ...

J. F. Power H. W. Sengpiel



Impact of Space Shuttle Support Facilities Construction on Special Interest Plant Species (Vandenberg AFB, Calif).  

National Technical Information Service (NTIS)

This report summarizes the results and conclusions of studies conducted to evaluate the impact of ground support facility construction for the Space Shuttle program at Vandenberg AFB, California on listed and proposed threatened or endangered plant specie...

R. C. Wooten D. Strutz R. Hudson



Germination Characteristics of Six Plant Species Growing on the Hanford Site.  

National Technical Information Service (NTIS)

Six plant species (Siberian and thickspike wheatgrass, cheatgrass, sand dropseed, Indian ricegrass, and Russian thistle) found on the Hanford Site were studied as part of an investigation into the revegetation of disturbed areas. Germination response to t...

G. R. Cox R. R. Kirkham J. F. Cline



Spatial and temporal variation in natural enemy assemblages on Maryland native plant species.  


Habitat manipulation is a branch of conservation biological control in which vegetation complexity and diversity are increased in managed landscapes to provide food and other resources for arthropod natural enemies. This is often achieved by maintaining noncrop plant material such as flowering strips and beetle banks that provide natural enemies with nectar and pollen, alternative prey, shelter from disturbance, and overwintering sites. In most cases, plant material used in habitat manipulation programs is not native to the area in which it is planted. Using native plant species in conservation biological control could serve a dual function of suppressing pest arthropod outbreaks and promoting other valuable ecosystem services associated with native plant communities. We evaluated 10 plant species native to Maryland for their attractiveness to foliar and ground-dwelling natural enemies. Plants that showed particular promise were Monarda punctata, Pycnanthemum tenuifolium, and Eupatorium hyssopifolium, which generally harbored the greatest abundance of foliar predators and parasitoids, although abundance varied over time. Among ground-dwelling natural enemies, total predator and parasitoid abundance differed between plant species, but carabid and spider abundance did not. Matching certain plant species and their allied natural enemies with specific pest complexes may be enhanced by identifying the composition of natural enemy assemblages at different times of year and in both foliar and ground habitat strata. PMID:18419920

Frank, Steven D; Shrewsbury, Paula M; Esiekpe, Okemeteri



Soil acidity and nutrient supply ratio as possible factors determining changes in plant species diversity in grassland and heathland communities  

Microsoft Academic Search

To elucidate the causes of the sharp decline in plant species diversity in heathland and nutrient-poor grasslands in The Netherlands, we investigated the spatial variation in plant species richness and the abundance of threatened plant species in relation to soil acidity and soil nutrient supply ratio. We selected 68 plots divided equally between species-rich and species-poor parts of the study

W. J Roem; F. Berendse



Competitive interactions between native and invasive exotic plant species are altered under elevated carbon dioxide.  


We hypothesized that the greater competitive ability of invasive exotic plants relative to native plants would increase under elevated CO(2) because they typically have traits that confer the ability for fast growth when resources are not limiting and thus are likely to be more responsive to elevated CO(2). A series of competition experiments under ambient and elevated CO(2) glasshouse conditions were conducted to determine an index of relative competition intensity for 14 native-invasive exotic species-pairs. Traits including specific leaf area, leaf mass ratio, leaf area ratio, relative growth rate, net assimilation rate and root weight ratio were measured. Competitive rankings within species-pairs were not affected by CO(2) concentration: invasive exotic species were more competitive in 9 of the 14 species-pairs and native species were more competitive in the remaining 5 species-pairs, regardless of CO(2) concentration. However, there was a significant interaction between plant type and CO(2) treatment due to reduced competitive response of native species under elevated compared with ambient CO(2) conditions. Native species had significantly lower specific leaf area and leaf area ratio under elevated compared with ambient CO(2). We also compared traits of more-competitive with less-competitive species, regardless of plant type, under both CO(2) treatments. More-competitive species had smaller leaf weight ratio and leaf area ratio, and larger relative growth rate and net assimilation rate under both ambient and elevated CO(2) conditions. These results suggest that growth and allocation traits can be useful predictors of the outcome of competitive interactions under both ambient and elevated CO(2) conditions. Under predicted future atmospheric CO(2) conditions, competitive rankings among species may not change substantially, but the relative success of invasive exotic species may be increased. Thus, under future atmospheric CO(2) conditions, the ecological and economic impact of some invasive exotic plants may be even greater than under current conditions. PMID:20809406

Manea, Anthony; Leishman, Michelle R



The influence of disturbance and habitat on the presence of non-native plant species along transport corridors  

Microsoft Academic Search

The impact from transportation corridors on surrounding habitat often reaches far beyond the edge of the corridor. The altered disturbance regime in plant communities along corridor edges and vehicle traffic facilitate the spread and establishment of invasive non-native plant species. We compared the frequency of non-native plant species along highways and railways and the ability of these species to invade

Malin J. Hansen; Anthony P. Clevenger



Flowering phenology of invasive alien plant species compared with native species in three Mediterranean-type ecosystems  

PubMed Central

Background and Aims Flowering phenology is a potentially important component of success of alien species, since elevated fecundity may enhance invasiveness. The flowering patterns of invasive alien plant species and related natives were studied in three regions with Mediterranean-type climate: California, Spain and South Africa's Cape region. Methods A total of 227 invasive–native pairs were compared for seven character types across the regions, with each pair selected on the basis that they shared the same habitat type within a region, had a common growth form and pollination type, and belonged to the same family or genus. Key Results Invasive alien plant species have different patterns of flowering phenology from native species in the three regions. Whether the alien species flower earlier, later or at the same time as natives depends on the climatic regime in the native range of the aliens and the proportion of species in the invasive floras originating from different regions. Species invading at least two of the regions displayed the same flowering pattern, showing that flowering phenology is a conservative trait. Invasive species with native ranges in temperate climates flower earlier than natives, those from Mediterranean-type climates at the same time, and species from tropical climates flower later. In California, where the proportion of invaders from the Mediterranean Basin is high, the flowering pattern did not differ between invasive and native species, whereas in Spain the high proportion of tropical species results in a later flowering than natives, and in the Cape region early flowering than natives was the result of a high proportion of temperate invaders. Conclusions Observed patterns are due to the human-induced sympatry of species with different evolutionary histories whose flowering phenology evolved under different climatic regimes. The severity of the main abiotic filters imposed by the invaded regions (e.g. summer drought) has not been strong enough (yet) to shift the flowering pattern of invasive species to correspond with that of native relatives. It does, however, determine the length of the flowering season and the type of habitat invaded by summer-flowering aliens. Results suggest different implications for impacts at evolutionary time scales among the three regions.

Godoy, Oscar; Richardson, David M.; Valladares, Fernando; Castro-Diez, Pilar



Species invasion alters local adaptation to soil communities in a native plant.  


Plant populations are often adapted to their local conditions, including abiotic factors as well as the biotic communities with which they interact. Soil communities, in particular, have strong effects on both the ecology and evolution of plant populations. Many invasive plant species alter the ecological relationships between native plants and soil communities; however, whether invaders also alter the evolutionary dynamics between native plants and soils is less well known. Here I show that populations of a native annual, Pilea pumila, shift from being maladapted to adapted to their local soil community with increasing history of invasion by Alliaria petiolata, an invader known to alter microbial communities. Additionally, native populations showed a signal of adaptation to soils of particular invasion stages, independent of local coevolutionary dynamics. These results suggest that invasive species affect not only the ecological, but also the evolutionary relationships of native species. PMID:23600238

Lankau, Richard A



Using habitat suitability models to target invasive plant species surveys.  


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 < 0.01), and targeted sampling did detect more species than nontargeted sampling with less sampling effort (chi2 = 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. PMID:23495636

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



Belowground nitrogen partitioning in experimental grassland plant communities of varying species richness.  


Partitioning of soil nitrogen (N) by niche separation among species may be an important mechanism explaining species coexistence and positive biodiversity-productivity relationships in terrestrial plant communities. However, there is little experimental evidence for such partitioning, in particular, as assessed across a gradient of species richness. In experimental communities of one, three, and six temperate grassland species in the field, we tested whether increasing species richness (1) decreases niche breadths of individual species, (2) decreases niche overlap among species, and (3) increases niche breadth of whole communities. Six N sources consisting of three different chemical forms of 15N-labeled N (15NO3(-), 15NH4+, 13C2-15N-glycine) injected at two soil depths (3 and 12 cm) were applied to each community. The chemical form and the soil depth of N characterize the niches for which niche breadth (Levins' B) and overlap (proportional similarity) were measured. After 48 hours, aboveground plant material was harvested to measure 15N enrichment. As expected, niche breadth of single species and niche overlap among species decreased with increased species richness, but community niche breadth did not increase. The decrease in niche breadth and niche overlap mostly occurred among subordinate species or pairs of subordinate and dominant species, rather than among dominant species. Species in the six-species mixtures mostly preferred NO3(-) from shallow soil. This may be partly explained by the presence of legumes in all six-species mixtures which allowed "N sparing" (i.e., increased availability of soil N since legumes rely more on atmospheric N2 than on soil N). Niche separation with respect to N uptake from different chemical forms and soil depths did not contribute much to facilitating the coexistence of dominant species, nor do our results suggest it as a major driver of positive diversity-ecosystem functioning relationships. However, partitioning of N may be important for the persistence of subordinate species. PMID:19537558

von Felten, Stefanie; Hector, Andrew; Buchmann, Nina; Niklaus, Pascal A; Schmid, Bernhard; Scherer-Lorenzen, Michael



Screening of plant species for inhibition of bacterial population of raw water  

Microsoft Academic Search

Seven plant species i.e., Adhatoda vasica, Andrographis paniculata, Azadirachta indica, Lawsonia inermis, Moringa oleifera, Ocimum sanctum and Trigonella foenum?graecum have been screened out systematically for their effectiveness in inhibition of bacterial population of raw water (in vitro) at variable pH level i.e., 6.0, 6.5, 7.0, 7.5 and 8.0. Maximum percentage inhibition was observed in three plant species at 6.5 pH

Sheo Kumar; Krishna Gopal



Cultivated plant species diversity in home gardens of an Amazonian peasant village in Northeastern Peru  

Microsoft Academic Search

Research on agrobiodiversity points to the importance of home gardens in situ conservation, yet few studies to date explicate\\u000a the origins and dynamics of plant species diversity. In this paper, we examine inter-household variations in cultivated plant\\u000a species diversity among house gardens in a traditional peasant community, near Iquitos, Peru. In-depth household interviews\\u000a (n = 24) and garden\\/field surveys reveal

Oliver T. Coomes; Natalie Ban



Potential Keystone Plant Species for the Frugivore Community at Tinigua Park, Colombia  

Microsoft Academic Search

Different practical problems restrict the possibility of rigorously testing the role of plants as keystone species in tropical\\u000a forests, and therefore we do not yet know the impacts that could result from their removal. Currently, the criteria used to\\u000a suggest keystone plant species in tropical forests include an assessment of their importance in supporting frugivore communities\\u000a during periods of fruit

Pablo Stevenson


Towards Discrimination of Plant Species by Machine Vision: Advanced Statistical Analysis of Chlorophyll Fluorescence Transients  

Microsoft Academic Search

Automatic discrimination of plant species is required for precision farming and for advanced environmental protection. For\\u000a this task, reflected sunlight has already been tested whereas fluorescence emission has been only scarcely considered. Here,\\u000a we investigated the discriminative potential of chlorophyll fluorescence imaging in a case study using three closely related\\u000a plant species of the family Lamiaceae. We compared discriminative potential

Anamika Mishra; Karel Matouš; Kumud B. Mishra; Ladislav Nedbal



Seed banking of endangered plants: are we conserving the right species to address climate change?  

Microsoft Academic Search

The increasing awareness of the effects of climate change on plant distributions in situ has made the appropriate application\\u000a of ex situ techniques more crucial. These ex situ conservation techniques need to be targeted to priority species identified\\u000a at risk from climate change. The present paper assesses the sensitivity of plant species to climate change in Belgium and\\u000a explores the

Sandrine Godefroid; Thierry Vanderborght



Variability of some plant species from different origins and their suitability for virus work  

Microsoft Academic Search

Plants of four species obtained from various sources were raised and compared for their suitability as test plants for a number of viruses. The species comprisedChenopodium amaranticolor (local lesion host of red clover mottle virus),Nicotiana glutinosa (local lesion host of tobacco mosaic virus (TMV)),N. rustica (systemic host of TMV, cucumber mosaic virus and tomato spotted wilt virus) andN. tabacum ‘White

M. L. Boerjan; D. Peters



Species delimitation and phylogeny of a New Zealand plant species radiation  

PubMed Central

Background Delimiting species boundaries and reconstructing the evolutionary relationships of late Tertiary and Quaternary species radiations is difficult. One recent approach emphasizes the use of genome-wide molecular markers, such as amplified fragment length polymorphisms (AFLPs) and single nucleotide polymorphisms (SNPs), to identify distinct metapopulation lineages as taxonomic species. Here we investigate the properties of AFLP data, and the usefulness of tree-based and non-tree-based clustering methods to delimit species and reconstruct evolutionary relationships among high-elevation Ourisia species (Plantaginaceae) in the New Zealand archipelago. Results New Zealand Ourisia are shown to comprise a geologically recent species radiation based on molecular dating analyses of ITS sequences (0.4–1.3 MY). Supernetwork analyses indicate that separate tree-based clustering analyses of four independent AFLP primer combinations and 193 individuals of Ourisia produced similar trees. When combined and analysed using tree building methods, 15 distinct metapopulations could be identified. These clusters corresponded very closely to species and subspecies identified on the basis of diagnostic morphological characters. In contrast, Structure and PCO-MC analyses of the same data identified a maximum of 12 and 8 metapopulations, respectively. All approaches resolved a large-leaved group and a small-leaved group, as well as a lineage of three alpine species within the small-leaved group. We were unable to further resolve relationships within these groups as corrected and uncorrected distances derived from AFLP profiles had limited tree-like properties. Conclusion Ourisia radiated into a range of alpine and subalpine habitats in New Zealand during the Pleistocene, resulting in 13 morphologically and ecologically distinct species, including one reinstated from subspecies rank. Analyses of AFLP identified distinct metapopulations consistent with morphological characters allowing species boundaries to be delimited in Ourisia. Importantly, Structure analyses suggest some degree of admixture with most species, which may also explain why the AFLP data do not exhibit sufficient tree-like properties necessary for reconstructing some species relationships. We discuss this feature and highlight the importance of improving models for phylogenetic analyses of species radiations using AFLP and SNP data.

Meudt, Heidi M; Lockhart, Peter J; Bryant, David



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


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



Different spatial organisation strategies of woody plant species in a montane cloud forest  

NASA Astrophysics Data System (ADS)

The coexistence of a high number of species in the forest is a central issue in tropical ecology. In this paper, we aim to characterise the spatial pattern of woody species in an Andean montane cloud forest to determine whether differences exist among the species in terms of spatial organization and if so, whether these differences are related to the life-form, primary dispersal mode, shade tolerance or the diameter distribution of the species. For this purpose, we analysed the spatial pattern of each species as well as the spatial relationships between young and adult individuals. Almost all the analysed species showed a cluster pattern, followed by a random pattern at larger distances. The cluster size is more evident for the young trees whereas adult trees tended to be more randomly distributed. The shade-tolerant species showed greater distances of aggregation than gap or medium-shade-tolerant species. Species primarily dispersed by wind and small birds showed larger distances of aggregation than species dispersed by mammals or big birds. All the under-story woody plants showed a notable cluster pattern, whereas canopy trees showed a variety of spatial patterns, with clustering at small scales being the most frequent. In the case of emergent trees, association was found between young and adult individuals on a large scale. Positive associations between young and adult individuals predominate at small scales for medium and shade tolerant species and at larger scales for bird-dispersed species whereas negative spatial associations at smaller scales were found for shade tolerant species and wind dispersed species. Our study confirms that conspecific organization varies among the woody plants in the analysed forest, and that the spatial pattern of woody plants is partially linked to shade tolerance, primary dispersal mode and life form of the species.

Ledo, Alicia; Montes, Fernando; Condés, Sonia



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.

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



Rapid plant identification using species- and group-specific primers targeting chloroplast DNA.  


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

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



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.

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



Soil biotic impact on plant species shoot chemistry and hyperspectral reflectance patterns.  


Recent studies revealed that plant-soil biotic interactions may cause changes in above-ground plant chemistry. It would be a new step in below-ground-above-ground interaction research if such above-ground chemistry changes could be efficiently detected. Here we test how hyperspectral reflectance may be used to study such plant-soil biotic interactions in a nondestructive and rapid way. The native plant species Jacobaea vulgaris and Jacobaea erucifolius, and the exotic invader Senecio inaequidens were grown in different soil biotic conditions. Biomass, chemical content and shoot reflectance between 400 and 2500 nm wavelengths were determined. The data were analysed with multivariate statistics. Exposing the plants to soil biota enhanced the content of defence compounds. The highest increase (400%) was observed for the exotic invader S. inaequidens. Chemical and spectral data enabled plant species to be classified with an accuracy > 85%. Plants grown in different soil conditions were classified with 50-60% correctness. Our data suggest that soil microorganisms can affect plant chemistry and spectral reflectance. Further studies should test the potential to study plant-soil biotic interactions in the field. Such techniques could help to monitor, among other things, where invasive exotic plant species develop biotic resistance or the development of hotspots of crop soil diseases. PMID:23025430

Carvalho, Sabrina; Macel, Mirka; Schlerf, Martin; Skidmore, Andrew K; van der Putten, Wim H



Plant species identification using Elliptic Fourier leaf shape analysis  

Microsoft Academic Search

Elliptic Fourier (EF) and discriminant analyses were used to identify young soybean (Glycine max (L.) merrill), sunflower (Helianthus pumilus), redroot pigweed (Amaranthus retroflexus) and velvetleaf (Abutilon theophrasti Medicus) plants, based on leaf shape. Chain encoded, Elliptic Fourier harmonic functions were generated based on leaf boundary. A complexity index of the leaf shape was computed using the variation between consecutive EF

João Camargo Neto; George E. Meyer; David D. Jones; Ashok K. Samal



Invasive plant species as potential bioenergy producers and carbon contributors  

Microsoft Academic Search

Current cellulosic bioenergy sources in the United States are being investigated in an effort to reduce dependence on foreign oil and the associated risks to national security and climate change (Koh and Ghazoul 2008; Demirbas 2007; Berndes et al. 2003). Multiple sources of renewable plant-based material have been identified and include agricultural and forestry residues, municipal solid waste, industrial waste,

S. Young; G. Gopalakrishnan; D. Keshwani



Xylem sap protein composition is conserved among different plant species  

Microsoft Academic Search

Xylem sap from broccoli ( Brassica oleracea L. cv. Calabrais), rape ( Brassica napus L. cv. Drakkar), pumpkin ( Cucurbita maxima Duch. cv. gelber Zentner) and cucumber ( Cucumis sativus L. cv. Hoffmanns Giganta) was collected by root pressure exudation from the surface of cut stems of healthy, adult plants. Total protein concentrations were in the range of 100 ?g ml ?1.

Anja Buhtz; Anna Kolasa; Kathleen Arlt; Christina Walz; Julia Kehr



Penicillium species endophytic in coffee plants and ochratoxin A production  

Microsoft Academic Search

Tissues from Coffea arabica, C. congensis, C. dewevrei and C. liberica collected in Colombia, Hawaii and at a local plant nursery in Maryland were sampled for the presence of fungal endophytes. Surface sterilized tissues including roots, leaves, stems and various berry parts were plated on yeast-malt agar. DNA was extracted from a set of isolates visually recognized as Penicillium, and

Fernando E. Vega; Francisco Posada; Stephen W. Peterson; Thomas J. Gianfagna; Fabio Chaves



Photoinhibition and recovery in tropical plant species: response to disturbance  

Microsoft Academic Search

Disturbance or rainforest is often followed by mass mortality of understorey seedlings. Transitions of shade grown plants to full sunlight can cause reductions in the efficiency with which light is used in photosynthesis, called photoinhibition. In order to assess the influence of photoinhibition on mortality and growth after rainforest disturbance this study examined photoinhibition in both simulated and real forest

C. E. Lovelock; C. B. Osmond; M. Jebb




Microsoft Academic Search

The performance of six native forest tree species, planted to restore forest in a degraded watershed in Doi Suthep-Pui National Park, Thailand and their responses to four fertiliser treatments are reported. The species were chosen for their potential to i) shade out competing weeds rapidly and ii) enhance tree species richness by attracting seed-dispersing wildlife. All species planted, except Gmelina

Stephen Elliott; Puttipong Navakitbumrung; Sudarat Zangkum; Cherdsak Kuarak; Janice Kerby; David Blakesley; Vilaiwan Anusarnsunthorn



Microsoft Academic Search

The distribution of riparian plant species is largely driven by hydrologic and soil variables, and riparian plant communities frequently occur in relatively distinct zones along streamside elevational and soil textural gradients. In two montane meadows in northeast Oregon, USA, we examined plant species distri- bution in three riparian plant communities—defined as wet, moist, and dry meadow—along short topographic gradients. We

Kathleen A. Dwire; J. Boone Kauffman; John E. Baham



Soil characteristics and plant exotic species invasions in the Grand Staircase—Escalante National Monument, Utah, USA  

Microsoft Academic Search

The Grand Staircase—Escalante National Monument (GSENM) contains a rich diversity of native plant communities. However, many exotic plant species have become established, potentially threatening native plant diversity. We sought to quantify patterns of native and exotic plant species and cryptobiotic crusts (mats of lichens, algae, and mosses on the soil surface), and to examine soil characteristics that may indicate or

Michael Bashkin; Thomas J. Stohlgren; Yuka Otsuki; Michelle Lee; Paul Evangelista; Jayne Belnap



Hoeflea suaedae sp. nov., an endophytic bacterium isolated from the root of the halophyte Suaeda maritima.  


A Gram-negative, aerobic, short rod-shaped bacterium, designated strain YC6898(T), was isolated from the surface-sterilized root of a halophyte (Suaeda maritima) inhabiting tidal flat of Namhae Island, Korea. Strain YC6898(T) grew optimally at 30-37 °C and pH 6.5-7.5. The strain inhibited mycelial growth of Pythium ultimum and Phytophthora capsici. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain YC6898(T) belongs to the genus Hoeflea in the family Phyllobacteriaceae. Its closest relatives were Hoeflea alexandrii AM1V30(T) (96.7% 16S rRNA gene sequence similarity), Hoeflea anabaenae WH2K(T) (95.7%), Hoeflea phototrophica DFL-43(T) (95.5%) and Hoeflea marina LMG 128(T) (94.8%). Strain YC6898(T) contained Q-10 as the major ubiquinone. The major fatty acids of strain YC6898(T) were C18:1?7c (61.1%), C16:0 (11.9%), 11-methyl C18:1?7c (9.6%) and C19:0 cyclo ?8c (8.0%). The polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol, unknown lipids and an unknown glycolipid. The total genomic DNA G+C content was 53.7 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic analysis, strain YC6898(T) represents a novel species of the genus Hoeflea, for which the name Hoeflea suaedae sp. nov. is proposed. The type strain is YC6898(T) (=KACC 14911(T)=NBRC 107700(T)). PMID:23159752

Chung, Eu Jin; Park, Jeong Ae; Pramanik, Prabhat; Bibi, Fehmida; Jeon, Che Ok; Chung, Young Ryun



[Species composition of Fusarium Link et Fr. fungal genera affecting agricultural plants and weeds in Uzbekistan].  


Phytopathogenic fungi of the Fusarium genus are represented on the agricultural plants and weeds by 17 species and 10 subspecies from the sections Roseum, Discolor, Sporotrichiella, Elegans, Martiella, Arachniotes in Uzbekistan. As to their occurrence frequency F. javanicum, F. lateritium, F. solani, F. oxysporum, F. heterosporum, F. moniliforme, F. gibbosum species are dominating ones. F. merismoides, F. redolens, F. nivale species occurred often F. sporotichiella, F. semitectum, F. culmorum, F. bucharicum, F. graminearum, F. avenaceum species occurred rarely. It was shown that the Fusarium species were more numerous in the central and southern regions of Uzbekistan than in the northern region. PMID:11785262

Sheraliev, A Sh; Bukharov, K; Kholmuradov, Ch


Shifts in species richness, herbivore specialization, and plant resistance along elevation gradients  

PubMed Central

Environmental gradients have been postulated to generate patterns of diversity and diet specialization, in which more stable environments, such as tropical regions, should promote higher diversity and specialization. Using field sampling and phylogenetic analyses of butterfly fauna over an entire alpine region, we show that butterfly specialization (measured as the mean phylogenetic distance between utilized host plants) decreases at higher elevations, alongside a decreasing gradient of plant diversity. Consistent with current hypotheses on the relationship between biodiversity and the strength of species interactions, we experimentally show that a higher level of generalization at high elevations is associated with lower levels of plant resistance: across 16 pairs of plant species, low-elevation plants were more resistant vis-à-vis their congeneric alpine relatives. Thus, the links between diversity, herbivore diet specialization, and plant resistance along an elevation gradient suggest a causal relationship analogous to that hypothesized along latitudinal gradients.

Pellissier, Loic; Fiedler, Konrad; Ndribe, Charlotte; Dubuis, Anne; Pradervand, Jean-Nicolas; Guisan, Antoine; Rasmann, Sergio




Technology Transfer Automated Retrieval System (TEKTRAN)

J.P. Grime's 'mass-ratio' hypothesis holds that ecosystem processes depend in the short term on functional properties of dominant plant species and in the longer term on how resident species influence the recruitment of potential dominants. The latter of these effects may be especially important am...


Plant species diversity in abandoned coppice forests in a temperate deciduous forest area of central Japan  

Microsoft Academic Search

We investigated plant species diversity as it related to stand structure and landscape parameters in abandoned coppice forests in a temperate, deciduous forest area of central Japan, where Fagus crenata was originally dominant. The species occurring in the study plots were classified into habitat types based on a statistical analysis of their occurrence bias in particular habitats (e.g., primary forest,

Takuo Nagaike; Tomohiko Kamitani; Tohru Nakashizuka



Insecticidal volatiles from the marigold plant (genus tagetes ). Effect of species and sample manipulation  

Microsoft Academic Search

Volatiles from three species of the genustagetes, commonly called marigold have been isolated and characterized. Simultaneous steam distillation extractions (SSDE) produced consistently extracts of higher insecticidal activity than Soxhlet extractions. Methylene chloride was the best solvent. Volatiles isolated from theminutae species showed higher activity than those frompatula anderecta. Comparison of extracts from the flower, foliage and roots of the plant

C. Wells; W. Bertsch; M. Perich




Microsoft Academic Search

Although invasive alien species (IAS) are a major threat to biodiversity, human health, and economy, our understanding of the factors controlling their distribution and abundance is limited. Here, we determine how environmental factors, land use, life-history traits of the invaders, residence time, origin, and human usage interact to shape the spatial pattern of invasive alien plant species in South Africa.

Wilfried Thuiller; David M. Richardson; Mathieu Rouget; ?erban Proche?; John R. U. Wilson



Status of Non-Native Plant Species, Tonto National Monument, Arizona.  

National Technical Information Service (NTIS)

A survey for non-native plant species was conducted in Tonto National Monument, western Gila County, Arizona, between March 23 and 27, 1988, and on November 19, 1988. Thirteen species were recorded during the survey, three of which were noted for the firs...

B. G. Phillips



Genome size stability in six medicinal plant species propagated in vitro  

Microsoft Academic Search

DNA content was estimated by flow cytometry in seedlings and in vitro clones of six species: Oenothera paradoxa, Inula verbascifolia ssp. aschersoniana, Rubus chamaemorus, Solidago virgaurea, S. graminifolia and Pueraria lobata. With the exception of P. lobata, there was no difference in genome sizes between seedlings and in vitro cultured plants from any species, indicative that they maintain their genetic

E. Sliwinska; B. Thiem



Effects of acid precipitation on reproduction in alpine plant species. [Erythronium grandiflorum; Aquilegia caerulea  

Microsoft Academic Search

A series of experiments were designed to determine the impact of acid rain on plant reproductive processes, a critical component of a species life history. Research was carried out in herbaceous alpine communities at the USDA (United States Department of Agriculture) Forest Service Glacier Lakes Ecosystem Experiments Site in the Snowy Mts. of Wyoming. A range of species were surveyed

M. A. McKenna; M. Hille-Salgueiro; R. C. Musselman



Assessing the risk of Glyphosate to native plants and weedy Brassicaceae species of North Dakota  

EPA Science Inventory

This study was conducted to determine the ecological risk to native plants and weedy Brassicaceae species which may be growing in areas affected by off target movement of glyphosate applied to glyphosate-resistant canola (Brassica napus). Ten native grass and forb species were ...


Index of Alien Impact: A Method for Evaluating Potential Ecological Impact of Alien Plant Species  

Microsoft Academic Search

Alien plant species are stressors to ecosystems and indicators of reduced ecosystem integrity. The magnitude of the stress reflects not only the quantity of aliens present, but also the quality of their interactions with native ecosystems. We develop an Index of Alien Impact ( IAI) to estimate the collective ecological impact of in situ alien species. IAI summarizes the frequency

Teresa K. Magee; Paul L. Ringold; Michael A. Bollman; Ted L. Ernst



Slow response of plant species richness to habitat loss and fragmentation  

Microsoft Academic Search

We examined the response of vascular plant species richness to long-term habitat loss and fragmentation of Estonian calcareous grasslands (alvars). The current number of habitat specialist species in 35 alvars was not explained by their current areas and connectivities but it was explained by their areas and connectivities 70 years ago (R2 ¼ 0.27). We estimated the magnitude of extinction

Aveliina Helm; Ilkka Hanski; Meelis Partel



Before, During and After: The Need for Long-term Monitoring in Invasive Plant Species Management  

Microsoft Academic Search

The invasion of non-indigenous plants is considered one of the primary threats to rare and endangered species as well as to the integrity and function of North American ecosystems. However, many of the suspected negative ecosystem impacts are based on anecdotal evidence. For example, there is almost unanimous agreement among natural resource managers of the detrimental ecological impacts of species

Bernd Blossey



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



Dual action of the active oxygen species during plant stress responses  

Microsoft Academic Search

Adaptation to environmental changes is crucial for plant growth and survival. However, the molecular and biochemical mechanisms of adaptation are still poorly understood and the signaling pathways involved remain elusive. Active oxygen species (AOS) have been proposed as a central component of plant adaptation to both biotic and abiotic stresses. Under such conditions, AOS may play two very different roles:

J. Dat; S. Vandenabeele; E. Vranova ´; M. Van Montagu; F. Van Breusegem



Occurrence of methylated arsenic species in parts of plants growing in polluted soils  

Microsoft Academic Search

Arsenic compounds were determined in extracts of branches, leaves and roots from plants growing in a mining contaminated area. The selected species were Dryopteris filix-max, Quercus pubescens, Dipsacus fullonum, Alnus glutinosa, Buxus sempervirens and Brachythecium cf. reflexum. Total arsenic content in the subsamples was analysed by ICPMS after acidic digestion. In general, concentrations in the plant parts followed the gradient

Maria Jose Ruiz-Chancho; Jose Fermín López-Sánchez; Roser Rubio



Why are there so many small plants? Implications for species coexistence  

Microsoft Academic Search

Summary 1 The prominently right-skewed distribution of species sizes has been the subject of a large literature in animal ecology, but has received comparatively little attention from plant ecologists. It is evident that not all explanations that have been offered for animals are directly applicable to plants. 2 We suggest three hypotheses that require further study in the interpretation of




Microsoft Academic Search

Herbicide tests were conducted between April 1984 and June 1986 on seven species of alien plants classified as threats to native ecosystems within Hawaii Volcanoes National Park. The study was designed to be an initial series of tests to develop effective alien plant treatment techniques and to obtain baseline information on the effects of herbicides on native flora. Highly effective

Gregory L. Santos; Dina Kageler; Donald E. Gardner; Linda W. Cuddihy; Charles P. Stone


Common Marsh Plant Species of the Gulf Coast Area. Volume I. Productivity.  

National Technical Information Service (NTIS)

As part of the U. S. Army Corps of Engineers Dredged Material Research Program, a study of the productivity of marsh plants common to the Gulf Coast area was conducted. The study reports on the productivity of seven marsh plant species in coastal marshes ...

J. G. Gosselink R. T. Parrondo C. S. Hopkinson




Microsoft Academic Search

Six ecologically diverse study sites viz., Khabeki, Khoora, Dape Sharif, Anga, Knotti Garden and Jallar were selected mainly on the basis of differences in their environmental attributes especially variations in elevation, slope, aspect, altitude, topography, soil composition, habitat, vegetation type and plant community. The available plant species at selected sites were enlisted. The ecological data was recorded during all the




Effect of Fe stress on utilization of Fe chelates by efficient and inefficient plant species  

Microsoft Academic Search

Using a double labelled Fe chelate (FeEDDHA) it has been possible to show that plants can take up Fe both, as an intact Fe chelate molecule and as ionic Fe after chelate splitting.The rate of chelate splitting in the roots is determined mainly by the Fe nutritional status of the particular plant species but also by the cation exchange capacity

V. Römheld; H. Marschner



Screening of plant species for the phytotreatment of wastewater containing sulphonated anthraquinones  

Microsoft Academic Search

Sulphonated anthraquinones are known to be recalcitrant to biodegradation and are not eliminated by traditional wastewater treatment plants, leading to their accumulation in fresh water. Due to the high cost and limited efficiency of existing physical–chemical treatments, alternative cheaper processes are required to remove these compounds from industrial effluents. Four plant species were tested under hydroponic conditions for their ability

Sylvie Aubert; Jean-Paul Schwitzguébel



Are herbage yield and yield stability affected by plant species diversity in sown pasture mixtures?  

Technology Transfer Automated Retrieval System (TEKTRAN)

A tenet of plant biodiversity theory in grasslands is that increased diversity contributes to the stability of ecosystems. In managed grasslands, such as pastures, greater stability of herbage production as a result of increased plant species diversity would be beneficial. In this study, I combined ...


Plant species effects and carbon and nitrogen cycling in a sagebrush–crested wheatgrass soil  

Microsoft Academic Search

Shifts in plant community structure in shrub and grass-dominated ecosystems are occurring over large land areas in the western US. It is not clear what effect this vegetative change will have on rates of carbon and nitrogen cycling, and thus long-term ecosystem productivity. To study the effect of different plant species on the decomposability of soil organic substrates and rates

Jian Chen; John M. Stark



Observation and Confirmation of Foliar Ozone Symptoms of Native Plant Species of Switzerland and Southern Spain  

Microsoft Academic Search

Tropospheric ozone is considered as the major pollutant of concern to the health and productivity of forests in the eastern United States and has more recently become of increasing concern within the forests of southern Europe. Recent observations have clearly demonstrated foliar injury symptoms to be occurring on many tree and native plant species within remote forested areas. Several plant

J. M. Skelly; J. L. Innes; J. E. Savage; K. R. Snyder; D. Vanderheyden; J. Zhang; M. J. Sanz



Effect of ploughing on plant species abundance and diversity in the northwestern coastal desert of Egypt  

Microsoft Academic Search

This study focuses on the effect of ploughing on plant abundance,vegetation cover, species richness, and taxonomic diversity during the growingseasons (winter and spring) of 1992 and 2000 in the habitat of inland plateau(natural habitat), 21 km south of Mersa-Matrouh (Egypt).Ninety-five species belonging to 27 families were recorded. High percentages oflife-forms and a large number of species were recorded in ploughed

Sania K. Hammouda; Selim Z. Heneidy



Multiple shoot induction and plant regeneration of the endangered species Crepis novoana  

Microsoft Academic Search

In vitro culture is a useful tool in the ex situ conservation of rare, endemic, and threatened plant species. Crepis novoana (Compositae) is an endangered endemic in northwestern Spain. Use of in vitro culture tools is necessary due to the poor conservation\\u000a status of populations of the species. The systems of in vitro propagation developed for this species in the present study\\u000a were caulogenesis

Patricia Corral; Rubén Mallón; Juan Rodríguez-Oubiña; María Luz González



Multichromosomal Genome Structure and Confirmation of Diazotrophy in Novel Plant-Associated Burkholderia Species?  

PubMed Central

Pulsed-field gel electrophoresis and 16S rRNA hybridization experiments showed that multichromosome genome structures and very large genome sizes (6.46 to 8.73 Mb) are prevalent in novel plant-associated Burkholderia species. 15N2 isotope dilution assays revealed unambiguous diazotrophy in these novel species. nifH gene sequence analysis, often used to determine phylogenetic relatedness among diazotrophs, showed tight clusters of Burkholderia species, which were clearly distinct from those of other diazotrophs.

Martinez-Aguilar, Lourdes; Diaz, Rafael; Pena-Cabriales, Juan Jose; Estrada-de los Santos, Paulina; Dunn, Michael F.; Caballero-Mellado, Jesus



Interactions between non-native plant species and the floristic composition of common habitats  

Microsoft Academic Search

Summary 1 We investigated the role of non-native species (neophytes) in common British plant communities using botanical data from two stratified random surveys carried out in 1990 and 1998. 2 We found that from 16 851 plots surveyed in 1998 there were 123 non-native species found mostly in arable, tall grass\\/herb and fertile grassland habitats. Invasive non-native species, e.g. Fallopia




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



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



Salt tolerance of salt marsh plants of Otago, New Zealand  

Microsoft Academic Search

The salt tolerance of 31 species — 29 halophytes constituting a large proportion of the more important species in salt marshes of Otago, and 2 glycophytes — was examined in water culture. The effects of salinity on growth and survival were the main parameters measured. There were considerable differences between species; most could not grow in sea water (3.5% NaCl),

T. R. Partridge; J. B. Wilson



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



A simple and efficient method for isolating small RNAs from different plant species  

PubMed Central

Background Small RNAs emerged over the last decade as key regulators in diverse biological processes in eukaryotic organisms. To identify and study small RNAs, good and efficient protocols are necessary to isolate them, which sometimes may be challenging due to the composition of specific tissues of certain plant species. Here we describe a simple and efficient method to isolate small RNAs from different plant species. Results We developed a simple and efficient method to isolate small RNAs from different plant species by first comparing different total RNA extraction protocols, followed by streamlining the best one, finally resulting in a small RNA extraction method that has no need of first total RNA extraction and is not based on the commercially available TRIzol® Reagent or columns. This small RNA extraction method not only works well for plant tissues with high polysaccharide content, like cactus, agave, banana, and tomato, but also for plant species like Arabidopsis or tobacco. Furthermore, the obtained small RNA samples were successfully used in northern blot assays. Conclusion Here we provide a simple and efficient method to isolate small RNAs from different plant species, such as cactus, agave, banana, tomato, Arabidopsis, and tobacco, and the small RNAs from this simplified and low cost method is suitable for downstream handling like northern blot assays.



Plant species richness drives the density and diversity of Collembola in temperate grassland  

NASA Astrophysics Data System (ADS)

Declining biodiversity is one of the most important aspects of anthropogenic global change phenomena, but the implications of plant species loss for soil decomposers are little understood. We used the experimental grassland community of the Jena Experiment to assess the response of density and diversity of Collembola to varying plant species richness, plant functional group richness and plant functional group identity. We sampled the experimental plots in spring and autumn four years after establishment of the experimental plant communities. Collembola density and diversity significantly increased with plant species and plant functional group richness highlighting the importance of the singular hypothesis for soil invertebrates. Generally, grasses and legumes beneficially affected Collembola density and diversity, whereas effects of small herbs usually were detrimental. These impacts were largely consistent in spring and autumn. By contrast, in the presence of small herbs the density of hemiedaphic Collembola and the diversity of Isotomidae increased in spring whereas they decreased in autumn. Beneficial impacts of plant diversity as well as those of grasses and legumes were likely due to increased root and microbial biomass, and elevated quantity and quality of plant residues serving as food resources for Collembola. By contrast, beneficial impacts of small herbs in spring probably reflect differences in microclimatic conditions, and detrimental effects in autumn likely were due to low quantity and quality of resources. The results point to an intimate relationship between plants and the diversity of belowground biota, even at small spatial scales, contrasting the findings of previous studies. The pronounced response of soil animals in the present study was presumably due to the fact that plant communities had established over several years. As decomposer invertebrates significantly impact plant performance, changes in soil biota density and diversity are likely to have major feedbacks on plant community productivity and composition.

Sabais, Alexander C. W.; Scheu, Stefan; Eisenhauer, Nico



Tropical Plant-Herbivore Networks: Reconstructing Species Interactions Using DNA Barcodes  

PubMed Central

Plants and their associated insect herbivores, represent more than 50% of all known species on earth. The first step in understanding the mechanisms generating and maintaining this important component of biodiversity is to identify plant-herbivore associations. In this study we determined insect-host plant associations for an entire guild of insect herbivores using plant DNA extracted from insect gut contents. Over two years, in a tropical rain forest in Costa Rica (La Selva Biological Station), we recorded the full diet breadth of rolled-leaf beetles, a group of herbivores that feed on plants in the order Zingiberales. Field observations were used to determine the accuracy of diet identifications using a three-locus DNA barcode (rbcL, trnH-psbA and ITS2). Using extraction techniques for ancient DNA, we obtained high-quality sequences for two of these loci from gut contents (rbcL and ITS2). Sequences were then compared to a comprehensive DNA barcode library of the Zingiberales. The rbcL locus identified host plants to family (success/sequence?=?58.8%) and genus (success/sequence?=?47%). For all Zingiberales except Heliconiaceae, ITS2 successfully identified host plants to genus (success/sequence?=?67.1%) and species (success/sequence?=?61.6%). Kindt’s sampling estimates suggest that by collecting ca. four individuals representing each plant-herbivore interaction, 99% of all host associations included in this study can be identified to genus. For plants that amplified ITS2, 99% of the hosts can be identified to species after collecting at least four individuals representing each interaction. Our study demonstrates that host plant identifications at the species-level using DNA barcodes are feasible, cost-effective, and reliable, and that reconstructing plant-herbivore networks with these methods will become the standard for a detailed understanding of these interactions.

Garcia-Robledo, Carlos; Erickson, David L.; Staines, Charles L.; Erwin, Terry L.; Kress, W. John



Plant hydraulics and photosynthesis of 34 woody species from different successional stages of subtropical forests.  


It is important to understand the ecophysiological characters of plants when exploring mechanisms underlying species substitution in the process of plant succession. In the present study, we selected 34 woody species from different stages of secondary succession in subtropical forests of southern China, and measured their hydraulic conductivity, gas exchange rates, leaf nutrients and drought-tolerance traits such as xylem resistance to cavitation, turgor loss point and carbon isotope ratio. Principal component analysis revealed that early-, mid- and late-successional species were significantly separated along axis 1, which was strongly associated with hydraulic-photosynthetic coordination. In contrast to species distributed in late-successional forest, early-successional species had the highest hydraulic conductivity, net photosynthetic rates, photosynthetic nitrogen and phosphorus use efficiencies, but had the lowest photosynthetic water-use efficiency. However, changes of the measured drought-tolerance traits of the 34 species along the succession did not demonstrate a clear trend - no significant correlations between these traits and plant successional stages were found. Moreover, the trade-off between hydraulic efficiency and safety was not identified. Taken together, our results suggested that hydraulic efficiency and photosynthetic function, rather than drought tolerance, play an important role in species distributions along plant succession in subtropical forests. PMID:23057774

Zhu, Shi-Dan; Song, Juan-Juan; Li, Rong-Hua; Ye, Qing



Generic and functional diversity in endophytic actinomycetes from wild Compositae plant species at South Sinai - Egypt.  


The diversity of culturable endophytic actinomycetes associated with wild Compositae plants is scantily explored. In this study, one hundred and thirty one endophytic actinobacteria were isolated from ten Compositae plant species collected from South Sinai in Egypt. Microscopic and chemotaxonomic investigation of the isolates indicated fourteen genera. Rare genera, such as Microtetraspora, and Intrasporangium, which have never been previously reported to be endophytic, were identified. Each plant species accommodated between three to eight genera of actinobacteria and unidentified strains were recovered from seven plant species. The generic diversity analysis of endophytic assemblages grouped the plant species into three main clusters, representing high, moderate and low endophytic diversity. The endophytes showed high functional diversity, based on forty four catabolic and plant growth promotion traits; providing some evidence that such traits could represent key criteria for successful residence of endophytes in the endosphere. Stress-tolerance traits were more predictive measure of functional diversity differences between the endophyte assemblages (Shannon's index, p = 0.01). The results indicate a potential prominent role of endophytes for their hosts and emphasize the potency of plant endosphere as a habitat for actinobacteria with promising future applications. PMID:23541473

El-Shatoury, Sahar A; El-Kraly, Omnia A; Trujillo, Martha E; El-Kazzaz, Waleed M; Gamal El-Din, El-Sayeda; Dewedar, Ahmed



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



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

SciTech Connect

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 conditions and supplied with 1 mg L{sup {minus}1} of each trace element individually for 10 d. Except B, all elements accumulated to much higher concentrations in roots than in shoots. Highest shoot tissue concentrations (mg kg{sup {minus}1} DW) of the various trace elements were attained by the following species: umbrella plant (Cyperus alternifolius L.) for Mn (198) and Cr (44); water zinnia (Wedelia trilobata Hitchc.) for Cd (148) and Ni (80); smartweed (Polygonum hydropiperoides Michx.) for Cu (95) and Pb (64); water lettuce (Pistia stratiotes L.) for Hg (92), As (34), and Se (39); and mare's tail (hippuris vulgaris L.) for B (1132). Whereas, the following species attained the highest root tissue concentrations (mg kg{sup {minus}1} DW); stripped rush (Baumia rubiginosa) for Mn (1683); parrot's feather (Myriophyllum brasiliense Camb.) for Cd (1426) and Ni (1077); water lettuce for Cu (1038), Hg (1217), and As (177); smartweed for Cr (2980) and Pb (1882); mare's tail for B (1277); and monkey flower (Mimulus guttatus Fisch.) for Se (384). From a phytoremediation perspective, smartweed was probably the best plant species for trace element removal from wastewater due to its faster growth and higher plant density.

Qian, J.H.; Zayed, A.; Zhu, Y.L.; Yu, M.; Terry, N.



Phylogenetic diversity of plants alters the effect of species richness on invertebrate herbivory.  


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

Dinnage, Russell



Heavy metal concentrations (Cd, Cu and Pb) in five aquatic plant species in Tasik Chini, Malaysia  

NASA Astrophysics Data System (ADS)

The purpose of this study was to determine the levels of heavy metals namely cadmium (Cd), copper (Cu) and lead (Pb) in the five aquatic plants. For this purpose, the concentration of heavy metals were measured in water and in the five aquatic plant species, Lepironia articulata, Pandanus helicopus, Scirpus grossus, Cabomba furcata and Nelumbo nucifera, in 15 sites from Tasik Chini. The concentrations were different among the plant species as well as among the parts of plants. The highest concentration of heavy metals among the aquatic plants and plant parts was found in the roots of S. grossus. The concentrations of Cd in the leaves and stems of submerged aquatic plant, C . furcata, were higher than concentration of Cd in the leaves and stems of emergent aquatic plant and floating leaf plant. The concentration of Cu in the stem of C. furcata was greater than that in the leaf, while the concentration of Cd was more in the leaf than in the stem. The heavy metal contents of the aquatic plants were in descending order of Pb > Cu > Cd. The metal concentration quotient of leaves/roots and stems/roots (ML/MR and MS/MR) were calculated. The highest internal translocation was found in P. helicopus, while the lowest internal translocation was found in S. grossus.

Ebrahimpour, M.; Mushrifah, I.



Bacterial Communities of Two Parthenogenetic Aphid Species Cocolonizing Two Host Plants across the Hawaiian Islands ?  

PubMed Central

Aphids (Hemiptera: Aphididae) have been the focus of several studies with respect to their interactions with inherited symbionts, but bacterial communities of most aphid species are still poorly characterized. In this research, we used bar-coded pyrosequencing to characterize bacterial communities in aphids. Specifically, we examined the diversity of bacteria in two obligately parthenogenetic aphid species (the melon aphid, Aphis gossypii, and the cardamom aphid, Pentalonia caladii) cocolonizing two plant species (taro, Colocasia esculenta, and ginger, Alpinia purpurata) across four Hawaiian Islands (Hawaii, Kauai, Maui, and Oahu). Results from this study revealed that heritable symbionts dominated the bacterial communities for both aphid species. The bacterial communities differed significantly between the two species, and A. gossypii harbored a more diverse bacterial community than P. caladii. The bacterial communities also differed across aphid populations sampled from the different islands; however, communities did not differ between aphids collected from the two host plants.

Jones, Ryan T.; Bressan, Alberto; Greenwell, April M.; Fierer, Noah



Arbuscular mycorrhizal fungi from New Caledonian ultramafic soils improve tolerance to nickel of endemic plant species.  


In order to improve knowledge about the role of arbuscular mycorrhizal fungi (AMF) in the tolerance to heavy metals in ultramafic soils, the present study investigated the influence of two Glomus etunicatum isolates from New Caledonian ultramafic maquis (shrubland), on nickel tolerance of a model plant species Sorghum vulgare, and of two ultramafic endemic plant species, Alphitonia neocaledonica and Cloezia artensis. In a first step, plants were grown in a greenhouse, on sand with defined concentrations of Ni, to appreciate the effects of the two isolates on the alleviation of Ni toxicity in controlled conditions. In a second step, the influence of the AMF on A. neocaledonica and C. artensis plants grown in a New Caledonian ultramafic soil rich in extractable nickel was investigated. Ni reduced mycorrhizal colonization and sporulation of the fungal isolates, but the symbionts increased plant growth and adaptation of endemic plant species to ultramafic conditions. One of the two G. etunicatum isolates showed a stronger positive effect on plant biomass and phosphorus uptake, and a greater reduction in toxicity symptoms and Ni concentration in roots and shoots. The symbionts seemed to act as a barrier to the absorption of Ni by the plant and reduced root-to-shoot Ni translocation. Results indicate the potential of selected native AMF isolates from ultramafic areas for ecological restoration of such degraded ecosystems. PMID:23588949

Amir, Hamid; Lagrange, Alexandre; Hassaïne, Nadine; Cavaloc, Yvon



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.

Gubsch, Marlen; Buchmann, Nina; Schmid, Bernhard; Schulze, Ernst-Detlef; Lipowsky, Annett; Roscher, Christiane



What is the phylogenetic placement of Dipteronia dyerana Henry? An example of plant species placement based on nucleotide sequences  

Microsoft Academic Search

DNA sequence data have been widely used to evaluate species delimitations and examine infraspecific relationships. However, species placements inferred from different nucleotide sequences are frequently in conflict. As an example of plant species placement based on nucleotide sequences, the phylogenetic placement of Dipteronia dyerana Henry (Aceraceae) was analyzed in the present study. The study species included eight Acer species (from

J. Yang; S. Li



Beyond the ecological: biological invasions alter natural selection on a native plant species.  


Biological invasions can have strong ecological effects on native communities by altering ecosystem functions, species interactions, and community composition. Even though these ecological effects frequently impact the population dynamics and fitness of native species, the evolutionary consequences of biological invasions have received relatively little attention. Here, I show that invasions impose novel selective pressures on a native plant species. By experimentally manipulating community composition, I found that the exotic plant Medicago polymorpha and the exotic herbivore Hypera brunneipennis alter the strength and, in some instances, the direction of natural selection on the competitive ability and anti-herbivore defenses of the native plant Lotus wrangelianus. Furthermore, the community composition of exotics influenced which traits were favored. For example, high densities of the exotic herbivore Hypera selected for increased resistance to herbivores in the native Lotus; however, when Medicago also was present, selection on this defense was eliminated. In contrast, selection on tolerance, another plant defense trait, was highest when both Hypera and Medicago were present at high densities. Thus, multiple exotic species may interact to influence the evolutionary trajectories of native plant populations, and patterns of selection may change as additional exotic species invade the community. PMID:18481527

Lau, Jennifer A



Metabolomics Unravel Contrasting Effects of Biodiversity on the Performance of Individual Plant Species  

PubMed Central

In spite of evidence for positive diversity-productivity relationships increasing plant diversity has highly variable effects on the performance of individual plant species, but the mechanisms behind these differential responses are far from being understood. To gain deeper insights into the physiological responses of individual plant species to increasing plant diversity we performed systematic untargeted metabolite profiling on a number of herbs derived from a grassland biodiversity experiment (Jena Experiment). The Jena Experiment comprises plots of varying species number (1, 2, 4, 8, 16 and 60) and number and composition of functional groups (1 to 4; grasses, legumes, tall herbs, small herbs). In this study the metabolomes of two tall-growing herbs (legume: Medicago x varia; non-legume: Knautia arvensis) and three small-growing herbs (legume: Lotus corniculatus; non-legumes: Bellis perennis, Leontodon autumnalis) in plant communities of increasing diversity were analyzed. For metabolite profiling we combined gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF-MS) and UPLC coupled to FT-ICR-MS (LC-FT-MS) analyses from the same sample. This resulted in several thousands of detected m/z-features. ANOVA and multivariate statistical analysis revealed 139 significantly changed metabolites (30 by GC-TOF-MS and 109 by LC-FT-MS). The small-statured plants L. autumnalis, B. perennis and L. corniculatus showed metabolic response signatures to increasing plant diversity and species richness in contrast to tall-statured plants. Key-metabolites indicated C- and N-limitation for the non-leguminous small-statured species B. perennis and L. autumnalis, while the metabolic signature of the small-statured legume L. corniculatus indicated facilitation by other legumes. Thus, metabolomic analysis provided evidence for negative effects of resource competition on the investigated small-statured herbs that might mechanistically explain their decreasing performance with increasing plant diversity. In contrast, taller species often becoming dominant in mixed plant communities did not show modified metabolite profiles in response to altered resource availability with increasing plant diversity. Taken together, our study demonstrates that metabolite profiling is a strong diagnostic tool to assess individual metabolic phenotypes in response to plant diversity and ecophysiological adjustment.

Scherling, Christian; Roscher, Christiane; Giavalisco, Patrick; Schulze, Ernst-Detlef; Weckwerth, Wolfram



Impacts of seedling herbivory on plant competition and implications for species coexistence  

PubMed Central

Background and Aims Although the causes and consequences of seedling herbivory for plant community composition are well understood, the mechanisms by which herbivores influence plant species recruitment to the established phase remain less clear. The aim was to examine how variation in the intensity of seedling herbivory interacts with growth-defence trade-offs and herbivore feeding preferences to affect plant community development. Methods Using 14-d-old seedlings of Trifolium pratense and T. repens, relative growth and susceptibility to herbivory by the snail Helix aspersa was quantified to elucidate putative growth-defence trade-offs for these species. Then mixed assemblages of 14-d-old Trifolium seedlings were exposed to herbivory by zero, two, five or ten snails and determined how variation in the intensity of herbivory affected competitive interactions into the mature phase (as measured by total plant biomass at 120 d old). Key Results In the absence of herbivory, communities were dominated by T. pratense; a result expected on the basis that it yielded larger and presumably more competitive seedlings. However, when seedlings were exposed to herbivory, the balance of competition shifted. At low levels of herbivory (two snails), both Trifolium species contributed equally to total plant biomass. More intense herbivory (five snails) resulted in almost total mortality of T. pratense and dominance of the mature community by T. repens. The most intense herbivory (ten snails) effectively removed all seedlings from the experimental community. Conclusions The study illustrates a mechanism whereby spatio-temporal fluctuations in seedling herbivory, when coupled with species-specific variation in competitive ability and sensitivity to herbivore attack, can differentially influence plant recruitment into the mature phase. This mechanism may be a key element in our attempts to understand plant species coexistence, since fluctuations in plant recruitment are fundamental to the many theories that view coexistence as a consequence of a spatio-temporal lottery for dominance over regeneration micro-sites.

Hanley, M. E.; Sykes, R. J.



Field observations of oviposition by a specialist herbivore on plant parts and plant species unsuitable as larval food.  


Where a female places her eggs can have a major impact on the fitness of her offspring, especially for insects in which the winged adults are far more mobile than the neonates. Larvae of Heliothis subflexa (Guenee) (Lepidoptera: Noctuidae), a specialist moth phylogenetically nested within a generalist clade, feed only on fruit of some Physalis species. Field observations of the oviposition behavior of H. subflexa revealed that 1) females laid most of their eggs on leaves of the Physalis plant, despite the larvae's frugivorous diet, and 2) females laid nearly 20% of the eggs on nonhost plant species. Most eggs oviposited on nonhosts were placed close to the host plant-88% were within 15 cm of the Physalis plant. However, in a study of neonate movement, we found that a distance of 2 cm from the hatch site to the host plant significantly decreased the ability of neonates to establish on the host plant. The estimated fitness cost, quantified as reduced neonate survival, for females ovipositing on nonhosts is 8-17%. Many ecological and evolutionary factors could result in oviposition on less suitable host parts and on nonhosts. One possibility is that specialization on Physalis has recently evolved in H. subflexa, and females have not fully optimized their oviposition behavior. However, the fitness cost of oviposition on nonhosts may be balanced by fitness benefits of such behavior, such as faster decision-making and reduced predation. PMID:22217764

Benda, Nicole D; Brownie, Cavell; Schal, Coby; Gould, Fred



An improved protocol for micropropagation of saltbush (Atriplex) species  

Technology Transfer Automated Retrieval System (TEKTRAN)

Atriplex griffithsii Standl is a threatened halophytic shrub found in saline soils of isolated regions within the desert basins in Southern New Mexico and Arizona. A related species within the genus, A. canescens, has been successfully micropropagated, suggesting that clonal propagation may offer a...


[Features of calcium crystals and calcium components in 54 plant species in salinized habitats of Tianjin].  


Plant calcium (Ca) is composed of dissociated Ca2+ and easily soluble, slightly soluble, and hard soluble combined Ca salts. The hard soluble Ca salts can often engender Ca crystals. To understand the Ca status in different growth form plants in salinized habitats, 54 plant species were sampled from the salinized habitats in Tianjin, with the Ca crystals examined by microscope and the Ca components determined by sequential fractionation procedure. More Ca crystals were found in 38 of the 54 plant species. In 37 of the 38 plant species, drusy and prismatic Ca oxalate crystals dominated, whereas the cystolith of Ca carbonate crystal only appeared in the leaves of Ficus carica of Moraceae. The statistics according to growth form suggested that deciduous arbors and shrubs had more Ca oxalate crystal, liana had lesser Ca oxalate crystal, and herbs and evergreen arbors had no Ca oxalate crystal. From arbor, shrub, liana to herb, the concentration of HCl-soluble Ca decreased gradually, while that of water soluble Ca was in adverse. The concentration of water soluble Ca in herbs was significantly higher than that in arbors and shrubs. This study showed that in salinized habitats, plant Ca crystals and Ca components differed with plant growth form, and the Ca oxalate in deciduous arbors and shrubs played an important role in withstanding salt stress. PMID:22919834

Xu, Jing-Jing; Ci, Hua-Cong; He, Xing-Dong; Xue, Ping-Ping; Zhao, Xue-Lai; Guo, Jian-Tan; Gao, Yu-Bao



In silico identification of conserved microRNAs in large number of diverse plant species  

PubMed Central

Background MicroRNAs (miRNAs) are recently discovered small non-coding RNAs that play pivotal roles in gene expression, specifically at the post-transcriptional level in plants and animals. Identification of miRNAs in large number of diverse plant species is important to understand the evolution of miRNAs and miRNA-targeted gene regulations. Now-a-days, publicly available databases play a central role in the in-silico biology. Because, at least ~21 miRNA families are conserved in higher plants, a homology based search using these databases can help identify orthologs or paralogs in plants. Results We searched all publicly available nucleotide databases of genome survey sequences (GSS), high-throughput genomics sequences (HTGS), expressed sequenced tags (ESTs) and nonredundant (NR) nucleotides and identified 682 miRNAs in 155 diverse plant species. We found more than 15 conserved miRNA families in 11 plant species, 10 to14 families in 10 plant species and 5 to 9 families in 29 plant species. Nineteen conserved miRNA families were identified in important model legumes such as Medicago, Lotus and soybean. Five miRNA families – miR319, miR156/157, miR169, miR165/166 and miR394 – were found in 51, 45, 41, 40 and 40 diverse plant species, respectively. miR403 homologs were found in 16 dicots, whereas miR437 and miR444 homologs, as well as the miR396d/e variant of the miR396 family, were found only in monocots, thus providing large-scale authenticity for the dicot- and monocot-specific miRNAs. Furthermore, we provide computational and/or experimental evidence for the conservation of 6 newly found Arabidopsis miRNA homologs (miR158, miR391, miR824, miR825, miR827 and miR840) and 2 small RNAs (small-85 and small-87) in Brassica spp. Conclusion Using all publicly available nucleotide databases, 682 miRNAs were identified in 155 diverse plant species. By combining the expression analysis with the computational approach, we found that 6 miRNAs and 2 small RNAs that have been identified only in Arabidopsis thus far, are also conserved in Brassica spp. These findings will be useful for tracing the evolution of small RNAs by examining their expression in common ancestors of the Arabidopsis-Brassica lineage.

Sunkar, Ramanjulu; Jagadeeswaran, Guru



Nematofauna associated with exotic and native leguminous plant species in West Africa: effect of Glomus intraradices arbuscular mycorrhizal symbiosis  

Microsoft Academic Search

Ten leguminous trees, four exotic species (Australian Acacia) and six indigenous species (three Sahelian Acacia spp. and three Sesbania spp.), were grown for 4 months in a natural Sahelian soil inoculated with or without the endomycorrhizal fungus, Glomus intraradices. In control trials, the determinant factor structuring the soil nematode fauna was the plant species, related plants having a similar influence on

Cécile Villenave; Khadi Leye; Jean-Luc Chotte; Robin Duponnois



Plant diversity in managed sal ( Shorea robusta Gaertn.) forests of Gorakhpur, India: species composition, regeneration and conservation  

Microsoft Academic Search

The sal (Shorea robusta) forest vegetation of Sohagibarawa Wildlife Sanctuary, Gorakhpur, India was analysed to assess plant diversity, regeneration pattern and the status of species conservation. A total of 208 plant species representing 165 genera and 72 families were recorded. Species richness, mean density and basal area of individuals in the observed forest were compared with those of other sal-dominated

S. K. Pandey; R. P. Shukla



Seasonal aspects of the invertebrate fauna of three species of plants and rock surfaces in a small stream  

Microsoft Academic Search

Macroinverbrates associated with three species of aquatic plants and those on rock surfaces in a stream were collected every two weeks from late May to late November. Some animals appeared to use all plants opportunistically as substrates from which food sources could be better exploited throughout the season. Others, usually of minor numerical importance, strongly differentiated between plant species and

J. Brian Rooke



Decline in gypsy moth ( Lymantria dispar ) performance in an elevated CO 2 atmosphere depends upon host plant species  

Microsoft Academic Search

Plant species differ broadly in their responses to an elevated CO2 atmosphere, particularly in the extent of nitrogen dilution of leaf tissue. Insect herbivores are often limited by the availability of nutrients, such as nitrogen, in their host plant tissue and may therefore respond differentially on different plant species grown in CO2-enriched environments. We reared gyspy moth larvae (Lymantria dispar)

M. B. Traw; R. L. Lindroth; F. A. Bazzaz



Comparative Analysis of Headspace Volatiles from Different Caterpillar-Infested or Uninfested Food Plants of Pieris Species  

Microsoft Academic Search

Plants that are infested by herbivores emit volatile cues that can be used by the natural enemies of the herbivores in their search for hosts. Based on results from behavioral studies, we investigated to what extent intact and herbivore-infested plant species and varieties from the food plant range of Pieris herbivore species differ in the composition of the volatile blends.

Jacqueline B. F. Geervliet; Maarten A. Posthumus; Louise E. M. Vet; Marcel Dicke



Enzyme activities during litter decomposition of two exotic and two native plant species in hardwood forests of New Jersey  

Microsoft Academic Search

Invasions by exotic plant species can alter ecosystem properties, including important soil functions and characteristics. As a result, decomposition of litter from the exotic, as well as native plants, can also be altered, leading to more profound changes in ecosystem functioning. We present here a study of eight enzyme activities during the decomposition of litter from four plant species, two

P. S Kourtev; J. G Ehrenfeld; W. Z Huang



Soil phosphorus and tree cover modify the effects of livestock grazing on plant species richness in Australian grassy woodland  

Microsoft Academic Search

The effects of grazing on the richness of understorey plant communities are predicted to vary along gradients of resources and tree cover. In temperate Australia livestock management has involved phosphorus addition and tree removal but little research has examined how the effects of grazing on plant species richness may vary with these management regimes. Patterns of understorey plant species richness

Josh Dorrough; Claire Moxham; Vivienne Turner; Geoff Sutter



Experimental analysis of the effect of exotic and native plant species on the structure and function of soil microbial communities  

Microsoft Academic Search

Invasions of exotic plant species are among the most pervasive and important threats to natural ecosystems, however, the effects of plant invasions on soil processes and the soil biota have rarely been investigated. We grew two exotic and a native under-story plant species in the same mineral soil from a non-invaded forest stand in order to test whether observed differences

P. S Kourtev; J. G Ehrenfeld; M Häggblom



Shifts in stomatal traits following the domestication of plant species.  


Stomata are the major gates regulating substrate availability for photosynthesis and water loss. Although both processes are critical to yield and to resource-use efficiency, we lack a comprehensive picture on how domestication and further breeding have impacted on leaf stomata. To fill this gap, stomatal sizes and densities were screened in cultivated and wild ancestor representatives of a uniquely large group of 24 herbaceous crops. Anatomical data and gas-exchange models were combined to compute maximum potential conductance to water, separately for upper and lower leaf sides. The evolution of maximum conductance under domestication was diverse. Several crops increased, others decreased (noticeably high-conductance species), and others kept a similar potential conductance following domestication. It was found that the contribution of upper leaf sides to maximum conductance was statistically higher in cultivated than in wild ancestors. For crops showing this response, reduced stomatal density in the lower side of domesticated leaves was responsible for the observed 'adaxialization' of conductance. Increases in the size of stomata at the upper epidermis played a comparatively minor role. Nevertheless, this overall response was varied in magnitude and direction, signalling crop-wise specificities. Observed patterns reflect only potential conductances based on anatomical traits and should be used with care until actual physiological outcomes are measured. Together with advancements in the developmental genetics of stomata, our findings might hint at new breeding avenues, focused on stomata distribution. Provided urgent needs for increasing yields, the opportunities of enhancing traits of the physiological relevance of stomata should not be ignored. PMID:23918960

Milla, Rubén; de Diego-Vico, Natalia; Martín-Robles, Nieves



A survey of California plant species with a portable VOC analyzer for biogenic emission inventory development  

NASA Astrophysics Data System (ADS)

An accurate estimate of the magnitude of biogenic volatile organic compound (BVOC) emissions in California's airsheds is critical for formulating effective strategies to reduce concentrations of fine particles, ozone, and other secondary air pollutants which affect human health and reduce yields of agricultural crops. However, California's natural and urban landscapes contain more than 6000 species, and the BVOC emissions from only a small fraction of these species have been characterized by quantitative measurements. A taxonomic method has been proposed to assign BVOC emission rate measurements to unmeasured species, but data are needed for additional plant families and genera to further develop and test this taxonomic approach. In the present study, BVOC emissions from more than 250 plant species were measured through a semi-quantitative method employing calibrated portable analyzers with photoionization detectors (PID). Replicate samples of live foliage were placed in plastic bags, in both light and darkened conditions, and the BVOC emissions categorized as low, medium or high. To validate our approach, for 63 plant species we compared our PID-measured BVOC emissions with published values, based on gas chromatography (GC) or GC-mass spectrometry, and found them to be well correlated. The method employed was more suited for detecting compounds with relatively higher emission rates, such as isoprene, than compounds with low emission rates, which could include monoterpenes and oxygenated compounds. For approximately 200 plant species not previously measured, the results provide further evidence that plant taxonomy can serve as a useful guide for generalizing the emissions behavior of many, but not all, plant families and genera.

Karlik, John F.; McKay, Alistair H.; Welch, Jason M.; Winer, Arthur M.


Rarity, species richness, and the threat of extinction--are plants the same as animals?  


Assessment of conservation status is done both for areas or habitats and for species (or taxa). IUCN Red List categories have been the principal method of categorising species in terms of extinction risk, and have been shown to be robust and helpful in the groups for which they have been developed. A recent study highlights properties associated with extinction risk in flowering plants, focusing on the species-rich hot spot of the Cape region of South Africa, and concludes that merely following methods derived from studies of vertebrates may not provide the best estimates of extinction risk for plants. Biology, geography, and history all are important factors in risk, and the study poses many questions about how we categorise and assess species for conservation priorities. PMID:21629675

Knapp, Sandra



Terrestrial Plant-Derived Anticancer Agents and Plant Species Used in Anticancer Research  

Microsoft Academic Search

Cancer is a major cause of death and the number of new cases, as well as the number of individuals living with cancer, is expanding continuously. Due to the enormous propensity of plants that synthesize mixtures of structurally diverse bioactive compounds, the plant kingdom is potentially a very diverse source of chemical constituents with tumor cytotoxic activity. Despite the successful

Spiridon E. Kintzios



Elevated CO2 and plant species diversity interact to slow root decomposition  

SciTech Connect

Changes in plant species diversity can result in synergistic increases in decomposition rates, while elevated atmospheric CO2 can slow the decomposition rates; yet it remains unclear how diversity and changes in atmospheric CO2 may interact to alter root decomposition. To investigate how elevated CO2 interacts with changes in root-litter diversity to alter decomposition rates, we conducted a 120-day laboratory incubation. Roots from three species (Trifolium repens, Lespedeza cuneata, and Festuca pratense) grown under ambient or elevated CO2 were incubated individually or in combination in soils that were exposed to ambient or elevated CO2 for five years. Our experiment resulted in two main findings: (1) Roots from T. repens and L. cuneata, both nitrogen (N) fixers, grown under elevated CO2 treatments had significantly slower decomposition rates than similar roots grown under ambient CO2 treatments; but the decomposition rate of F. pratense roots (a non-N-fixing species) was similar regardless of CO2 treatment. (2) Roots of the three species grown under ambient CO2 and decomposed in combination with each other had faster decomposition rates than when they were decomposed as single species. However, roots of the three species grown under elevated CO2 had similar decomposition rates when they were incubated alone or in combination with other species. These data suggest that if elevated CO2 reduces the root decomposition rate of even a few species in the community, it may slow root decomposition of the entire plant community.

De Graaff, Marie-Anne [ORNL; Schadt, Christopher Warren [ORNL; Rula, Kelly L [ORNL; Six, Johan W U A [University of California, Davis; Schweitzer, Jennifer A [ORNL; Classen, Aimee T [University of Tennessee, Knoxville (UTK)



Nutrient Foraging Traits in Ten Co-occurring Plant Species of Contrasting Life Forms  

SciTech Connect

Morphological responses of the root system were tested by assessing scale, precision, discrimination, and sensitivity. Observations of high variation between species in scale, precision and sensitivity. In herbaceous species alone, scale and precision were positively correlated. Sensitivity was not closely related to precision, indicating that proliferation of roots in fertile patches does not always yield growth benefits in heterogeneous soils. Plant life form was not correlated with precision or sensitivity; however, scale of response was greater in herbs than in woody plants-possibly due to different root growth rates.

Einsmann, J.C.; Jones, R.H.; Pu, M.; Mitchell, R.J.



Leaf hydraulics and drought stress: response, recovery and survivorship in four woody temperate plant species.  


Efficient conduction of water inside leaves is essential for leaf function, yet the hydraulic-mediated impact of drought on gas exchange remains poorly understood. Here we examine the decline and subsequent recovery of leaf water potential (Psi(leaf)), leaf hydraulic conductance (K(leaf)), and midday transpiration (E) in four temperate woody species exposed to controlled drought conditions ranging from mild to lethal. During drought the vulnerability of K(leaf) to declining Psi(leaf) varied greatly among the species sampled. Following drought, plants were rewatered and the rate of E and K(leaf) recovery was found to be strongly dependent on the severity of the drought imposed. Gas exchange recovery was strongly correlated with the relatively slow recovery of K(leaf) for three of the four species, indicating conformity to a hydraulic-stomatal limitation model of plant recovery. However, there was also a shift in the sensitivity of stomata to Psi(leaf) suggesting that the plant hormone abscisic acid may be involved in limiting the rate of stomatal reopening. The level of drought tolerance varied among the four species and was correlated with leaf hydraulic vulnerability. These results suggest that species-specific variation in hydraulic properties plays a fundamental role in steering the dynamic response of plants during recovery. PMID:19627564

Blackman, Christopher J; Brodribb, Timothy J; Jordan, Gregory J



Adaptive Management Plan for Sensitive Plant Species on the Nevada Test Site  

SciTech Connect

The Nevada Test Site supports numerous plant species considered sensitive because of their past or present status under the Endangered Species Act and with federal and state agencies. In 1998, the U.S. Department of Energy, Nevada Operation Office (DOE/NV) prepared a Resource Management Plan which commits to protects and conserve these sensitive plant species and to minimize accumulative impacts to them. This document presents the procedures of a long-term adaptive management plan which is meant to ensure that these goals are met. It identifies the parameters that are measured for all sensitive plant populations during long-term monitoring and the adaptive management actions which may be taken if significant threats to these populations are detected. This plan does not, however, identify the current list of sensitive plant species know to occur on the Nevada Test Site. The current species list and progress on their monitoring is reported annually by DOE/NV in the Resource Management Plan.

C. A. Wills



Effects of plant species identity, diversity and soil fertility on biodegradation of phenanthrene in soil.  


The work presented in this paper investigated the effects of plant species composition, species diversity and soil fertility on biodegradation of (14)C-phenanthrene in soil. The two soils used were of contrasting fertility, taken from long term unfertilised and fertilised grassland, showing differences in total nitrogen content (%N). Plant communities consisted of six different plant species: two grasses, two forbs, and two legume species, and ranged in species richness from 1 to 6. The degradation of (14)C-phenanthrene was evaluated by measuring indigenous catabolic activity following the addition of the contaminant to soil using respirometry. Soil fertility was a driving factor in all aspects of (14)C-phenanthrene degradation; lag phase, maximum rates and total extents of (14)C-phenanthrene mineralisation were higher in improved soils compared to unimproved soils. Plant identity had a significant effect on the lag phase and extents of mineralisation. Soil fertility was the major influence also on abundance of microbial communities. PMID:23202655

Oyelami, Ayodeji O; Okere, Uchechukwu V; Orwin, Kate H; De Deyn, Gerlinde B; Jones, Kevin C; Semple, Kirk T



Relationship between nutritional composition of plant species and infestation levels of thrips.  


Levels of soluble protein and carbohydrate (raffinose, sucrose, glucose, and fructose) in leaves from a selection of plant species were measured to determine if a relationship existed between these nutrients and infestation by Frankliniella occidentalis and Heliothrips haemorrhoidalis. Most species of host plant examined contained a higher proportion of protein than carbohydrates, and overall, leaves from species of plants that supported populations of thrips had greater levels of protein than leaves from nonhost species. New leaves and flowers that supported F. occidentalis contained high levels of carbohydrate and protein. The quantity of pr