Science.gov

Sample records for alfalfa plants grown

  1. Antioxidant responses in soybean and alfalfa plants grown in DDTs contaminated soils: Useful variables for selecting plants for soil phytoremediation?

    PubMed

    Mitton, Francesca M; Ribas Ferreira, Josencler L; Gonzalez, Mariana; Miglioranza, Karina S B; Monserrat, José M

    2016-06-01

    Phytoremediation is a low-cost alternative technology based on the use of plants to remove pollutants from the environment. Persistent organic pollutants such as DDTs with a long half-life in soils are attractive candidates for remediation. This study aimed to determine the potential of antioxidant response use in the evaluation of plants' tolerance for selecting species in phytoremediation purposes. Alfalfa and soybean plants were grown in DDT contaminated soils. After 60days, growth, protein content, antioxidant capacity, GST activity, concentration of proteic and non-proteic thiol groups, chlorophyll content and carotenoid content were measured in plant tissues. Results showed no effect on alfalfa or soybean photosynthetic pigments but different responses in the protein content, antioxidant capacity, GST activity and thiol groups on roots, stems and leaves, indicating that DDTs affected both species. Soybean showed higher susceptibility than alfalfa plants due to the lower antioxidant capacity and GST activity in leaves, in spite of having the lowest DDT accumulation. This study provides new insights into the role of oxidative stress as an important component of the plant's response to DDT exposure. PMID:27155479

  2. Plant bugs on alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper treats the most important plant bugs, or Miridae, found on alfalfa in North America. It is estimated that more than 10 species of plant bugs have the potential to develop on this important forage legume. Of these, the alfalfa plant bug (Adelphocoris lineolatus), pale legume bug (Lygus e...

  3. Dig Alfalfa Plants to Assess Root Rots and Yield Potential

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Digging alfalfa plants and inspecting their crowns and roots for rot is critical to assess stand health and production potential. Brown root rot (BRR) has been a significant plant disease on alfalfa for decades but until recently was thought to only cause significant damage in western Canada. With i...

  4. Alfalfa

    MedlinePlus

    ... your health provider.Medications that increase sensitivity to sunlight (Photosensitizing drugs)Some medications can increase sensitivity to sunlight. Large doses of alfalfa might also increase your ...

  5. Plant development controls leaf area expansion in alfalfa plants competing for light

    PubMed Central

    Baldissera, Tiago Celso; Frak, Ela; Carvalho, Paulo Cesar de Faccio; Louarn, Gaëtan

    2014-01-01

    Background and Aims The growth of crops in a mixture is more variable and difficult to predict than that in pure stands. Light partitioning and crop leaf area expansion play prominent roles in explaining this variability. However, in many crops commonly grown in mixtures, including the forage species alfalfa, the sensitivity and relative importance of the physiological responses involved in the light modulation of leaf area expansion are still to be established. This study was designed to assess the relative sensitivity of primary shoot development, branching and individual leaf expansion in alfalfa in response to light availability. Methods Two experiments were carried out. The first studied isolated plants to assess the potential development of different shoot types and growth periods. The second consisted of manipulating the intensity of competition for light using a range of canopies in pure and mixed stands at two densities so as to evaluate the relative effects on shoot development, leaf growth, and plant and shoot demography. Key Results Shoot development in the absence of light competition was deterministic (constant phyllochrons of 32·5 °Cd and 48·2 °Cd for primary axes and branches, branching probability of 1, constant delay of 1·75 phyllochron before axillary bud burst) and identical irrespective of shoot type and growth/regrowth periods. During light competition experiments, changes in plant development explained most of the plant leaf area variations, with average leaf size contributing to a lesser extent. Branch development and the number of shoots per plant were the leaf area components most affected by light availability. Primary axis development and plant demography were only affected in situations of severe light competition. Conclusions Plant leaf area components differed with regard to their sensitivity to light competition. The potential shoot development model presented in this study could serve as a framework to integrate light responses

  6. Geothermal energy savings for a New Zealand alfalfa drying plant

    SciTech Connect

    van de Wydeven, F.; Freeston, D.H.

    1980-12-01

    The existing alfalfa drying plant was analyzed to determine the efficiency and cost of energy use per unit of production. Further studies are reported of possibilities for energy savings both in the existing plant and in the future development which will incorporate a second dryer and treble the output. (MHR)

  7. Genetically engineered alfalfa and feral alfalfa plants: What should growers know?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa subsp. sativa L) is the world’s most important forage crop. The western United States is the most important production area for both alfalfa forage and alfalfa seed. Alfalfa was the first major perennial genetically-engineered (GE)crop and a GE trait for resistance to glypho...

  8. Selecting Rhizobium meliloti for inoculation of alfalfa planted in acid soils

    SciTech Connect

    Lowendorf, H.S.; Alexander, M.

    1983-01-01

    The study was conducted to obtain Rhizobium meliloti strains suitable for use with alfalfa grown in acid soils. Thirteen strains of R. meliloti were examined for their ability to grow in acidified culture media and seven of these were characterized for the ability to surive in acid and limed nonsterile soils or grow in the presence of the host legume, Medicago sativa L. The pH values of the most acid, defined medium that permitted growth of the bacteria from a small inoculum ranged from pH 5.3 to 6.0. For R. meliloti 411SE1 and GH1-1SE1, the minimum pH that allowed for growth, the critical pH, was not a dependable indicator of survival in a more acid medium. Strains of R. meliloti with relatively low critical pH values survived better in a limed soil but not in acid soils than strains with higher critical pH values. Three strains of R. meliloti previously identified as good inoculants for alfalfa in acid soils did not consistently survive beter than other strains in a planted or unplanted acid soil of pH 5.3. However, the plants increase the population densities of these three strains more than other strains. These results suggest that R. meliloti strains suitable for inoculation of alfalfa in acid soils may be selected not by simple saprophytic properties but by their stimulation by the host legume in acid soils.

  9. Relationship between photosynthetic capacity, nitrogen assimilation and nodule metabolism in alfalfa (Medicago sativa) grown with sewage sludge.

    PubMed

    Antolín, M Carmen; Fiasconaro, M Laura; Sánchez-Díaz, Manuel

    2010-10-15

    Sewage sludge has been used as N fertilizer because it contains some of inorganic N, principally as nitrate and ammonium ions. However, sewage sludge addition to legumes could result in impaired nodule metabolism due to the presence of inorganic N from sludge. A greenhouse experiment was conducted to examine the effects of sewage sludge on growth, photosynthesis, nitrogen assimilation and nodule metabolism in alfalfa (Medicago sativa L. cv. Aragón). Plants were grown in pots with a mixture of perlite and vermiculite (2:1, v/v). The experiment included three treatments: (1) plants inoculated with rhizobia and amended with sewage sludge at rate of 10% (w/w) (RS); (2) plants inoculated with rhizobia without any amendment (R); and (3) non-inoculated plants fed with ammonium nitrate (N). N(2)-fixing plants had lower growth and sucrose phosphate synthase activity but higher photosynthesis than nitrate-fed plants because they compensated the carbon cost of the rhizobia. However, sewage sludge-treated plants evidenced a loss of carbon sink strength due to N(2) fixation by means of decreased photosynthetic capacity, leaf chlorophylls and N concentration in comparison to untreated plants. Sewage sludge did no affect nodulation but decreased nodule enzyme activities involved in carbon and N metabolisms that may lead to accumulation of toxic N-compounds. PMID:20591568

  10. INFLUENCE OF ENHANCED MALATE DEHYDROGENASE EXPRESSION BY ALFALFA ON DIVERSITY OF RHIZOBACTERIA AND SOIL NUTRIENT AVAILABILITY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgenic alfalfa over-expressing a nodule-enhanced malate dehydrogenase (neMDH) cDNA and untransformed alfalfa plants were grown at the same field site and rhizosphere soils collected after 53 weeks of plant growth. These alfalfa lines differ in the amount and composition of root organic acids pro...

  11. Alfalfa (Medicago sativa L.).

    PubMed

    Fu, Chunxiang; Hernandez, Timothy; Zhou, Chuanen; Wang, Zeng-Yu

    2015-01-01

    Alfalfa (Medicago sativa L.) is a high-quality forage crop widely grown throughout the world. This chapter describes an efficient protocol that allows for the generation of large number of transgenic alfalfa plants by sonication-assisted Agrobacterium-mediated transformation. Binary vectors carrying different selectable marker genes that confer resistance to phosphinothricin (bar), kanamycin (npt II), or hygromycin (hph) were used to generate transgenic alfalfa plants. Intact trifoliates collected from clonally propagated plants in the greenhouse were sterilized with bleach and then inoculated with Agrobacterium strain EHA105. More than 80 % of infected leaf pieces could produce rooted transgenic plants in 4-5 months after Agrobacterium-mediated transformation. PMID:25300843

  12. Production of a diagnostic monoclonal antibody in perennial alfalfa plants.

    PubMed

    Khoudi, H; Laberge, S; Ferullo, J M; Bazin, R; Darveau, A; Castonguay, Y; Allard, G; Lemieux, R; Vézina, L P

    1999-07-20

    The increasing use of monoclonal antibodies (mAbs) in diagnostic reagents necessitates efficient and cost-effective mAb production methods. In blood banks, one of the most routinely used reagents is the anti-human IgG reagent used for the detection of non-agglutinating antibodies. Here we report the production of a functional, purified anti-human IgG, through the expression of its encoding genes in perennial transgenic alfalfa. Transgenic plants expressing the light- and heavy-chain encoding mRNAs were obtained, and plants from crosses were found to express fully assembled C5-1. The purification procedure yielded mainly the H2L2 form with specificity and affinity identical to those of hybridoma-derived C5-1. The ability to accumulate the antibody was maintained both in parental F1 lines during repeated harvesting and in clonal material; the antibody was stable in the drying hay as in extracts made in pure water. Also, plant and hybridoma-derived C5-1 had similar in vivo half-lives in mice. These results indicate that plant C5-1 could be used in a diagnostic reagent as effectively as hybridoma-derived C5-1, and demonstrates the usefulness of perennial systems for the cost-effective, stable, and reliable production of large amounts of mAbs. PMID:10397849

  13. Complete genome sequence of a new enamovirus from Argentina infecting alfalfa plants showing dwarfism symptoms.

    PubMed

    Bejerman, Nicolás; Giolitti, Fabián; Trucco, Verónica; de Breuil, Soledad; Dietzgen, Ralf G; Lenardon, Sergio

    2016-07-01

    Alfalfa dwarf disease, probably caused by synergistic interactions of mixed virus infections, is a major and emergent disease that threatens alfalfa production in Argentina. Deep sequencing of diseased alfalfa plant samples from the central region of Argentina resulted in the identification of a new virus genome resembling enamoviruses in sequence and genome structure. Phylogenetic analysis suggests that it is a new member of the genus Enamovirus, family Luteoviridae. The virus is tentatively named "alfalfa enamovirus 1" (AEV-1). The availability of the AEV-1 genome sequence will make it possible to assess the genetic variability of this virus and to construct an infectious clone to investigate its role in alfalfa dwarfism disease. PMID:27068164

  14. Transgenic Alfalfa Plants Expressing the Sweetpotato Orange Gene Exhibit Enhanced Abiotic Stress Tolerance

    PubMed Central

    Wang, Zhi; Ke, Qingbo; Kim, Myoung Duck; Kim, Sun Ha; Ji, Chang Yoon; Jeong, Jae Cheol; Lee, Haeng-Soon; Park, Woo Sung; Ahn, Mi-Jeong; Li, Hongbing; Xu, Bingcheng; Deng, Xiping; Lee, Sang-Hoon; Lim, Yong Pyo; Kwak, Sang-Soo

    2015-01-01

    Alfalfa (Medicago sativa L.), a perennial forage crop with high nutritional content, is widely distributed in various environments worldwide. We recently demonstrated that the sweetpotato Orange gene (IbOr) is involved in increasing carotenoid accumulation and enhancing resistance to multiple abiotic stresses. In this study, in an effort to improve the nutritional quality and environmental stress tolerance of alfalfa, we transferred the IbOr gene into alfalfa (cv. Xinjiang Daye) under the control of an oxidative stress-inducible peroxidase (SWPA2) promoter through Agrobacterium tumefaciens-mediated transformation. Among the 11 transgenic alfalfa lines (referred to as SOR plants), three lines (SOR2, SOR3, and SOR8) selected based on their IbOr transcript levels were examined for their tolerance to methyl viologen (MV)-induced oxidative stress in a leaf disc assay. The SOR plants exhibited less damage in response to MV-mediated oxidative stress and salt stress than non-transgenic plants. The SOR plants also exhibited enhanced tolerance to drought stress, along with higher total carotenoid levels. The results suggest that SOR alfalfa plants would be useful as forage crops with improved nutritional value and increased tolerance to multiple abiotic stresses, which would enhance the development of sustainable agriculture on marginal lands. PMID:25946429

  15. Mercury localization and speciation in plants grown hydroponically or in a natural environment.

    PubMed

    Carrasco-Gil, Sandra; Siebner, Hagar; Leduc, Danika L; Webb, Samuel M; Millán, Rocío; Andrews, Joy C; Hernández, Luis E

    2013-04-01

    Better understanding of mercury (Hg) accumulation, distribution, and speciation in plants is required to evaluate potential risks for the environment and to optimize phytostabilization strategies for Hg-contaminated soils. The behavior of Hg in alfalfa (Medicago sativa) plants grown under controlled conditions in a hydroponic system (30 μM HgCl2) was compared with that of naturally occurring Horehound (Marrubium vulgare) plants collected from a mining soil polluted with Hg (Almadenejos, Spain) to characterize common mechanisms of tolerance. Synchrotron X-ray Fluorescence microprobe (μ-SXRF) showed that Hg accumulated at the root apex of alfalfa and was distributed through the vascular system to the leaves. Transmission electron microscopy (TEM) implied association of Hg with cell walls, accompanied by their structural changes, in alfalfa roots. Extended X-ray absorption fine structure (EXAFS) determined that Hg was principally bound to biothiols and/or proteins in M. sativa roots, stems, and leaves. However, the major fraction of Hg detected in M. vulgare plants consisted of mineral species, possibly associated with soil components. Interestingly, the fraction of Hg bound to biothiols/proteins (i.e., metabolically processed Hg) in leaves of both plants (alfalfa and M. vulgare) was similar, in spite of the big difference in Hg accumulation in roots, suggesting that some tolerance mechanisms might be shared. PMID:23406525

  16. Alfalfa hay induced primary photosensitization in horses.

    PubMed

    Puschner, B; Chen, X; Read, D; Affolter, V K

    2016-05-01

    Photosensitization, also known as photodermatitis, occurs when phototoxic or photoactive substances accumulate in the skin and interact with sunlight to result in an often severe, crusting, itching or painful dermatitis in unpigmented and/or lightly haired areas of the skin. Primary photosensitization, caused by direct ingestion of photosensitizing agents, has been reported anecdotally in horses after ingestion of alfalfa hay. Between 2004 and 2014, several large outbreaks of primary photosensitization in horses fed primarily alfalfa hay were investigated in California. Alfalfa hay samples were collected and carefully examined for the presence of known photosensitizing plants and pesticide residues but none were identified. Select hay samples were evaluated for unusual fungal infestation and for phototoxicity assay using a specific Candida albicans assay; results were negative. In the 2004 outbreak, a feeding study was conducted with three horses exclusively fed alfalfa hay that was suspected to have caused the outbreak. Two weeks after ingestion of alfalfa hay, two horses developed several lesions in non-pigmented skin characterized as chronic ulcerative and necrotizing dermatitis with superficial vasculitis, which was consistent with photosensitization. In the 2014 outbreak, seven different implicated alfalfa hay samples were analyzed for chlorophyll a and b, and pheophorbide a. These compounds had been suspected to play a role in alfalfa-induced primary photosensitization. The chlorophyll contents ranged from 0.90 to 2.30 mg/g in the alfalfa hay samples, compared to 1.37 and 2.94 mg/g in locally grown alfalfa and orchard grass hay. The pheophorbide a levels ranged from 3.36 to 89.87 µg/g in alfalfa samples compared to 81.39 and 42.33 µg/g in control alfalfa and orchard grass hay samples. These findings eliminate chlorophyll a, chlorophyll b, and pheophorbide a as possible causes for alfalfa-hay induced primary photosensitization. PMID:27040919

  17. Asymmetric somatic hybrid plants between Medicago sativa L. (alfalfa, lucerne) and Onobrychis viciifolia Scop. (sainfoin).

    PubMed

    Li, Y G; Tanner, G J; Delves, A C; Larkin, P J

    1993-12-01

    This paper reports on the production of intergeneric somatic hybrid plants between two sexually incompatible legume species. Medicago sativa (alfalfa, lucerne) leaf protoplasts were inactivated by lethal doses of iodoacetamide. Onobrychis viciifolia (sainfoin) suspension-cell protoplasts were gamma-irradiated at lethal doses. Following electrofusion under optimized conditions about 50,000 viable heterokaryons were produced in each test. The fusion products were cultured with the help of alfalfa nurse protoplasts. Functional complementation permitted only the heterokaryons to survive. A total of 706 putative heterokaryon-derived plantlets were regenerated and 570 survived transplantation to soil. Experimentation was aimed at the introduction of proanthocyanidins (condensed tannins) from sainfoin, a bloat-safe plant, to alfalfa, a bloat-causing forage crop; however, no tannin-positive regenerant plants were detected. Most regenerant plants have shown morphological differences from the fusion parents, although, as expected, all resembled the "recipient" parent, alfalfa. Southern analysis using an improved total-genomic probing technique has shown low levels of sainfoin-specific DNA in 43 out of 158 tested regenerants. Cytogenetic analysis of these asymmetric hybrids has confirmed the existence of euploid (2n=32; 17%) as well as aneuploid (2n=30, 33-78; 83%) plants. Pollen germination tests have indicated that the majority of the hybrids were fertile, while 35% had either reduced fertility or were completely sterile. PMID:24190318

  18. Adenylate cyclase activity in a higher plant, alfalfa (Medicago sativa).

    PubMed Central

    Carricarte, V C; Bianchini, G M; Muschietti, J P; Téllez-Iñón, M T; Perticari, A; Torres, N; Flawiá, M M

    1988-01-01

    An adenylate cyclase activity in Medicago sativa L. (alfalfa) roots was partially characterized. The enzyme activity remains in the supernatant fluid after centrifugation at 105,000 g and shows in crude extracts an apparent Mr of about 84,000. The enzyme is active with Mg2+ and Ca2+ as bivalent cations, and is inhibited by EGTA and by chlorpromazine. Calmodulin from bovine brain or spinach leaves activates this adenylate cyclase. PMID:3128270

  19. USDA-ARS Plant Science Research Unit, St. Paul Alfalfa/Forage Research Program

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Plant Science Research Unit (PSRU) located at the University of Minnesota in St. Paul receives approximately $1.5 million to fund the research of six scientists who direct their research efforts toward developing new uses and improved traits for alfalfa. Our overarching goal is to develop alfalf...

  20. Efficacy of a BVDV subunit vaccine produced in alfalfa transgenic plants.

    PubMed

    Peréz Aguirreburualde, María Sol; Gómez, María Cristina; Ostachuk, Agustín; Wolman, Federico; Albanesi, Guillermo; Pecora, Andrea; Odeon, Anselmo; Ardila, Fernando; Escribano, José M; Dus Santos, María José; Wigdorovitz, Andrés

    2013-02-15

    Bovine viral diarrhea virus (BVDV) is considered an important cause of economic loss within bovine herds worldwide. In Argentina, only the use of inactivated vaccines is allowed, however, the efficacy of inactivated BVDV vaccines is variable due to its low immunogenicity. The use of recombinant subunit vaccines has been proposed as an alternative to overcome this difficulty. Different studies on protection against BVDV infection have focused the E2 protein, supporting its putative use in subunit vaccines. Utilization of transgenic plants expressing recombinant antigens for the formulation of experimental vaccines represents an innovative and cost effective alternative to the classical fermentation systems. The aim of this work was to develop transgenic alfalfa plants (Medicago sativa, L.) expressing a truncated version of the structural protein E2 from BVDV fused to a molecule named APCH, that target to antigen presenting cells (APCH-tE2). The concentration of recombinant APCH-tE2 in alfalfa leaves was 1 μg/g at fresh weight and its expression remained stable after vegetative propagation. A methodology based an aqueous two phases system was standardized for concentration and partial purification of APCH-tE2 from alfalfa. Guinea pigs parentally immunized with leaf extracts developed high titers of neutralizing antibodies. In bovine, the APCH-tE2 subunit vaccine was able to induce BVDV-specific neutralizing antibodies. After challenge, bovines inoculated with 3 μg of APCH-tE2 produced in alfalfa transgenic plants showed complete virological protection. PMID:23291101

  1. Ensifer, Phyllobacterium and Rhizobium species occupy nodules of Medicago sativa (alfalfa) and Melilotus alba (sweet clover) grown at a Canadian site without a history of cultivation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phage resistant and susceptible bacteria from nodules of alfalfa and sweet clover grown at a site without a known history of cultivation, were identified as Ensifer, Rhizobium and Phyllobacterium species based on sequence analysis of ribosomal (16S and 23S rRNA)and protein encoding (atpD and recA) g...

  2. [Molecular identification of intergeneric somatic hybrid plants between alfalfa and sainfoin].

    PubMed

    Xu, Z Q; Jia, J F

    2000-03-01

    Somatic hybrid plants between alfalfa and sainfoin were regenerated by protoplast fusion and culture. DNA samples of the hybrid plants, hydroxyproline-resistant sainfoin plants, alfalfa cell line transformed with Agrobacterium tumefaciens 702 were isolated with a new and simple method. The hybridity was identified by random amplified polymorphic DNAs and Southern hybridization. Significant differences can be seen in the sequences amplified, which are specific for each parent/primer combination under the amplification conditions used. In 20 random oligonucleotide primers used, six could amplified more DNA fragments and had better polymorphisms. The results suggested that besides containing nuclear substances of two parents, the hybrid genome was inclined to eliminate sainfoin chromosome with DNA reconstruction. However, the somatic genome also could produce the sainfoin-specified DNA fragments which further confirmed by Southern hybridization. The hybrids were asymmetric and had certain regeneration ability just because the intervention of sainfoin DNA. PMID:10976321

  3. Micromonospora from nitrogen fixing nodules of alfalfa (Medicago sativa L.). A new promising Plant Probiotic Bacteria.

    PubMed Central

    Martínez-Hidalgo, Pilar; Galindo-Villardón, Purificación; Igual, José M.; Martínez-Molina, Eustoquio

    2014-01-01

    Biotic interactions can improve agricultural productivity without costly and environmentally challenging inputs. Micromonospora strains have recently been reported as natural endophytes of legume nodules but their significance for plant development and productivity has not yet been established. The aim of this study was to determine the diversity and function of Micromonospora isolated from Medicago sativa root nodules. Micromonospora-like strains from field alfalfa nodules were characterized by BOX-PCR fingerprinting and 16S rRNA gene sequencing. The ecological role of the interaction of the 15 selected representative Micromonospora strains was tested in M. sativa. Nodulation, plant growth and nutrition parameters were analyzed. Alfalfa nodules naturally contain abundant and highly diverse populations of Micromonospora, both at the intra- and at interspecific level. Selected Micromonospora isolates significantly increase the nodulation of alfalfa by Ensifer meliloti 1021 and also the efficiency of the plant for nitrogen nutrition. Moreover, they promote aerial growth, the shoot-to-root ratio, and raise the level of essential nutrients. Our results indicate that Micromonospora acts as a Rhizobia Helper Bacteria (RHB) agent and has probiotic effects, promoting plant growth and increasing nutrition efficiency. Its ecological role, biotechnological potential and advantages as a plant probiotic bacterium (PPB) are also discussed. PMID:25227415

  4. Aluminum effects on the polypeptide composition of sensitive and tolerant alfalfa plants

    SciTech Connect

    Elkhatib, H.; Foster, J.G.; Baligar, V.C.; Bennett, O.L.

    1986-04-01

    Appalachian hill-land soils are acidic and have high levels of exchangeable Al that limit utilization of many commercially available forage species such as alfalfa. A comparison of native alfalfa plants collected from such environments (OK-1), survivors from seedings to such environments (Elkins), and Al-sensitive plants of a commercial variety (ARC) will indicate whether biochemical constituents confer Al tolerance. Plants propagated vegetatively from each variety have been cultured in nutrient solution under optimal conditions (0 Al, pH 6.5) or stressed with 90, 130, or 170 ..mu..M Al at pH 4.5 for 2 weeks. Results show that OK-1 was the most tolerant variety, based on fresh weights of roots and shoots, leaf number, root length, and protein concentration. ARC was sensitive to high Al concentrations while Elkins was intermediate in its response. Roots and leaves of the Al-sensitive variety also possessed a unique, 27 kD polypeptide that disappeared upon exposure of the plants to high levels of Al. These results lay the foundation for further biochemical analyses and subsequent development and release of an alfalfa variety for acid soils.

  5. Effect of air sparging on fate and transport of trichloroethylene in chambers with alfalfa plants

    SciTech Connect

    Zhang, Q.; Hu, J.; Erickson, L.E.; Davis, L.C.

    1997-12-31

    To study the effect of air sparging in soil with trichloroethylene present as a dense nonaqueous phase, air was supplied through pipes installed at the bottom of two chambers planted with alfalfa. Air input rate was 2.14 L/m{sup 2}/day. The fate of trichloroethylene (TCE) was investigated by monitoring TCE concentration in both outflow groundwater and soil gas. Comparison of these results with those of the previous study without air sparging indicates that air sparging appreciably increases the groundwater concentration of TCE. The soil gas at the surface shows even greater concentration difference. The flux of TCE to the atmosphere is increased significantly by air input. Accordingly, the authors can conclude that air sparging improved mass transfer of TCE from the nonaqueous phase to groundwater phase. Air sparging appeared to negatively impact the health of the alfalfa because of the elevated TCE present in the vadose zone of the chamber.

  6. Alfalfa endophytes as novel sources of antimicrobial compounds that inhibit the growth of human and plant pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungal endophytes may contribute to plant health and disease protection, yet little is known about their various roles in alfalfa. Also, endophytes from several plant species produce novel antimicrobial compounds that may be useful clinically. We isolated endophytic fungi from over 50 samples from s...

  7. Prickly lettuce control in alfalfa seed production.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weeds are particularly troublesome in alfalfa grown for seed due to the wider row spacing and the lack of multiple cuttings compared to alfalfa grown for hay. Prickly lettuce is often an escape weed in alfalfa seed production fields as it can germinate throughout the entire year and is naturally tol...

  8. Do glyphosate resistant feral plants and hay fields spread the transgene to conventional alfalfa seed fields?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In addition to meeting domestic needs, large amounts of alfalfa seed and hay produced in the US are being exported overseas. Because alfalfa is an insect pollinated crop, gene flow is a concern. Adding to this alfalfa readily naturalizes along roadsides, irrigation ditches, and unmanaged habitats; a...

  9. Nucleolus in clinostat-grown plants

    SciTech Connect

    Shen-Miller, J.; Dannenhoffer, J. ); Hinchman, R. )

    1991-05-01

    The clinostat is an apparatus that is used to mimic zero gravity in studies of plant growth in the absence of gravitropic response. Clinostat-grown tissue cultures of carrot exhibit significant increases both in the number of nuclei containing more than one nucleolus and in nucleolar volume. Oat seedlings germinated and grown on clinostats exhibit a decreased rate of shoot elongation, increased tissue sensitivity to applied auxin, and an increased response to gravitropic stimulation. Clinostat treatment clearly affects plant metabolism. The nucleolus is the region in the nucleus where ribosome synthesis and assembly take place. The 18S, 5.8S, and 25S ribosomal genes, in tandem units, are located in the nucleolus. Ribosomes orchestrate the production of all proteins that are necessary for the maintenance of cell growth, development, and survival. A full study of the effects of nullification of gravitropism, by clinostat rotation, on nucleolar development in barley has been initiated. The authors study developmental changes of nucleolar number and diameter in clinostat-grown root tissues. Preliminary results show that barley roots exhibit changes in nucleolar number and diameter. Growth rates of barley root and shoot also appear to be reduced, in measurements of both length and weight.

  10. Drought and alfalfa nutrition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although established alfalfa can access deep subsoil water, dry topsoils limit the availability of many nutrients. Dry topsoils can limit the uptake of many plant nutrients. With the potential for drought in 2007, farmers should consider fertilizing alfalfa if the soil tends to be droughty, is shall...

  11. Manure on alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many managers of crop-livestock operations could, or need to, utilize alfalfa fields in their manure management plans. The advantages to manure application on alfalfa need to be considered in the context of some potential concerns – plant damage from manure or wheel traffic, pathogen transmission in...

  12. Manure use on alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Manure application to alfalfa is often necessary because of limited application windows during the year and limited land-to-livestock ratios to meet Comprehensive Nutrient Management Plan requirements. Manure applied before alfalfa planting or during production can improve yield and performance of t...

  13. Alfalfa witches'-broom

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa witches'-broom was first reported in 1969 in Australia and later in South Africa, Canada, and Saudi Arabia. More recently, specific phytoplasmas associated with alfalfa witches'-broom have been identified from symptomatic plants in the United States (Wisconsin), Italy, Lithuania, Oman, Ira...

  14. THE EFFECT OF RAINFALL ON THE ABUNDANCE OF TARNISHED PLANT BUG [LYGUS LINEOLARIS (PALISOT)] NYMPHS IN ALFALFA FIELDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During a 13-year field study in northwestern New Jersey, total May-June rainfall ranged from 6.5 to 10.7 inches (165-272mm). The highest rainfall reduced first generation nymphs of the tarnished plant bug, Lygus lineolaris (Palisot) (Miridae), in alfalfa by 50%. This reduction was likely mechanica...

  15. Distribution of glassy-winged sharpshooter and threecornered alfalfa hopper on plant hosts in the San Joaquin valley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Homalodisca vitripennis Germar and Spissistilus festinus Say populations were surveyed bimonthly for 14 months in Kern County at five agricultural sites made up of a variety of potential host plants. Additionally, S. festinus populations were surveyed in four alfalfa fields in Kern and Tulare Counti...

  16. Preference by sheep for endophyte-infected tall fescue grown adjacent to or at a distance from alfalfa.

    PubMed

    Friend, M A; Provenza, F D; Villalba, J J

    2015-03-01

    Two experiments were conducted to assess preference by sheep for endophyte-infected tall fescue growing in monoculture at least 5 m away from alfalfa (fescue-middle (FM)) over endophyte-infected tall fescue growing adjacent (0.2 to 1 m; fescue-alfalfa (FA)) to alfalfa (FA), and the effect of legume scent on preference for endophyte-infected tall fescue. In Experiment 1, 10 six-month-old lambs were offered for 12 days a choice of freshly harvested FA and FM. On days 13 and 14, lambs were offered the same choice, except cages (to allow access only to scent) containing freshly harvested alfalfa were put in the feeders containing FA, whereas cages containing freshly harvested FM were included with the feeders containing FM. Forage intake was measured 1 h after feeding and at three consecutive 2-h intervals thereafter. FA contained greater (P<0.002) concentrations of the alkaloid ergovaline (360 ± 27 ppm) and CP (8 ± 0.4%) than FM (219 ± 27 ppm and 6 ± 0.4%, respectively). Lambs preferred (P<0.05) FA to FM during the 1st hour of feeding, but the differences became smaller and disappeared in later feeding periods (P<0.005). Lambs offered FA with alfalfa scent or FM with FM scent preferred (P<0.05) FA but only on the 2nd day. In Experiment 2, 10 six-month-old lambs were offered a choice of FM with cages (to allow access only to scent) containing freshly harvested alfalfa or FM for 8 days. During the following 4 days, FM in the cages was replaced with freshly harvested sainfoin. Preference was greater (P<0.05) for FM offered with alfalfa scent than for FM offered with FM scent only on days 4 and 8. When lambs were offered FM with alfalfa or sainfoin in cages, they preferred (P<0.05) tall fescue with sainfoin scent over fescue with alfalfa scent, but intake was variable across hours and days (P<0.001). It is concluded that (1) lambs adjusted their intake of and preference for FA and FM over successive feeding bouts within each day, likely owing to an attempt to balance

  17. Plant growth and soil microbial community structure of legumes and grasses grown in monoculture or mixture.

    PubMed

    Chen, Meimei; Chen, Baodong; Marschner, Petra

    2008-01-01

    A greenhouse pot experiment was conducted to investigate the influence of soil moisture content on plant growth and the rhizosphere microbial community structure of four plant species (white clover, alfalfa, sudan grass, tall fescue), grown individually or in a mixture. The soil moisture content was adjusted to 55% or 80% water holding capacity (WHC). The results indicated that the total plant biomass of one pot was lower at 55% WHC. At a given soil moisture, the total plant biomass of white clover and tall fescue in the mixture was lower than that in a monoculture, indicating their poor competitiveness. For leguminous plants, the decrease in soil moisture reduced the total microbial biomass, bacterial biomass, fungal biomass, and fungal/bacterial ratio in soil as assessed by the phospholipid fatty acid analysis, whereas, lower soil moisture increased those parameters in the tall fescue. The microbial biomass in the soil with legumes was higher than that in the soil with grasses and the two plant groups differed in soil microbial community composition. At high soil moisture content, microbial communities of the plant mixture were similar to those of the legume monoculture, and the existence of legumes in the mixture enhanced the bacterial and fungal biomass in the soil compared to the grasses grown in the monoculture, indicating that legumes played a dominant role in the soil microbial community changes in the plant mixture. PMID:19143348

  18. Stress-related phenomena and detoxification mechanisms induced by common pharmaceuticals in alfalfa (Medicago sativa L.) plants.

    PubMed

    Christou, Anastasis; Antoniou, Chrystalla; Christodoulou, Charalampia; Hapeshi, Evroula; Stavrou, Ioannis; Michael, Costas; Fatta-Kassinos, Despo; Fotopoulos, Vasileios

    2016-07-01

    Pharmaceutically active compounds (PhACs) have been recently shown to exert phytotoxic effects. The present study explores the uptake, systemic translocation, and abiotic stress responses and detoxification mechanisms induced by the exposure of alfalfa plants grown in sand under greenhouse conditions to four common, individually applied PhACs (10μgL(-1)) (diclofenac, sulfamethoxazole, trimethoprim, 17a-ethinylestradiol) and their mixture. Stress physiology markers (lipid peroxidation, proline, H2O2 and NO content, antioxidant activity assays) and gene expression levels of key plant detoxification components (including glutathione S-transferases, GST7, GST17; superoxide dismutases, CuZnSOD, FeSOD; proton pump, H(+)-ATP, and cytochrome c oxidase, CytcOx), were evaluated. PhACs were detected in significantly higher concentrations in roots compared with leaves. Stress related effects, manifested via membrane lipid peroxidation and oxidative burst, were local (roots) rather than systemic (leaves), and exacerbated when the tested PhACs were applied in mixture. Systemic accumulation of H2O2 in leaves suggests its involvement in signal transduction and detoxification responses. Increased antioxidant enzymatic activities, as well as upregulated transcript levels of GST7, GST17, H(+)-ATPase and CytcOx, propose their role in the detoxification of the selected PhACs in plants. The current findings provide novel biochemical and molecular evidence highlighting the studied PhACs as an emerging abiotic stress factor, and point the need for further research on wastewater flows under natural agricultural environments. PMID:27037887

  19. Sustainable biomass energy production and rural economic development using alfalfa as feedstock

    SciTech Connect

    DeLong, M.M.; Swanberg, D.R.; Oelke, E.A.

    1995-11-01

    Alfalfa is a well-known and widely-planted crop that offers environmental and soil conservation advantages when grown as a 4-year segment in a 7-year rotation with corn and soybeans. Alfalfa fixes nitrogen from the air, thereby enhancing soil nitrogen and decreasing the need for manufactured nitrogen fertilizer. With alfalfa yields of 4 dry tons per acre per year and with separate alfalfa leaves being sold as a high-value animal feed, separated alfalfa stems can be economically viable fuel feedstock for a gasifier combined cycle power plant. This paper reports on a feasibility study for an integrated biomass power system, where an energy crop (alfalfa) is coupled to a processing plant and a power plant (integrated gasification combined cycle with hot gas cleanup) in a way that benefits the joint venture of an alfalfa producers cooperative and a utility entity. The sale of a mid-level protein animal feed co-product and electricity both support the production cost of alfalfa. The co-product/fuel processing operation uses a common train of equipment, thereby requiring neither product to carry the total cost. The power plant provides an important continuous demand for the feedstock and results in continuous supply of leaf product to provide a reliable supply needed for the leaf meal product.

  20. Seeding Rate Effect on Establishment and Yield of Alfalfa in Bermudagrass Sod

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Establishing alfalfa often requires field conversion from another forage species. Planting alfalfa into bermudagrass sod reduces risk of forage loss because bermudagrass would remain if alfalfa was not successfully established. Previous Arkansas experiments on establishing alfalfa in bermudagrass so...

  1. Assessment of heat shock protein 70 induction by heat in alfalfa varieties and constitutive overexpression in transgenic plants.

    PubMed

    Ferradini, Nicoletta; Iannacone, Rina; Capomaccio, Stefano; Metelli, Alessandra; Armentano, Nadia; Semeraro, Lucia; Cellini, Francesco; Veronesi, Fabio; Rosellini, Daniele

    2015-01-01

    Heat shock proteins (HSPs) are molecular chaperones involved in many cellular functions. It has been shown that mammalian cytosolic HSP70 binds antigenic peptides mediating the activation of the immune system, and that it plays a determining role in tumour immunogenicity. This suggests that HSP70 may be used for the production of conjugated vaccines. Human and plant HSPs share high sequence similarity and some important biological functions in vitro. In addition, plant HSPs have no endotoxic side effects. Extraction of HSP70 from plants for use as vaccine adjuvant requires enhancing its concentration in plant tissues. In this work, we explored the possibility to produce HSP70 in both transgenic and non-transgenic plants, using alfalfa as a model species. First, a transcriptional analysis of a constitutive and an inducible HSP70 genes was conducted in Arabidopsis thaliana. Then the coding sequence of the inducible form was cloned and introduced into alfalfa by Agrobacterium-mediated transformation, and the accumulation of the protein in leaf tissue of transgenic plants was demonstrated. We also tested diverse alfalfa varieties for heat-inducible expression of endogenous HSP70, revealing variety-specific responses to heat shock. PMID:25951604

  2. Sugar-binding activity of pea lectin enhances heterologous infection of transgenic alfalfa plants by Rhizobium leguminosarum biovar viciae.

    PubMed

    van Rhijn, P; Fujishige, N A; Lim, P O; Hirsch, A M

    2001-05-01

    Transgenic alfalfa (Medicago sativa L. cv Regen) roots carrying genes encoding soybean lectin or pea (Pisum sativum) seed lectin (PSL) were inoculated with Bradyrhizobium japonicum or Rhizobium leguminosarum bv viciae, respectively, and their responses were compared with those of comparably inoculated control plants. We found that nodule-like structures formed on alfalfa roots only when the rhizobial strains produced Nod factor from the alfalfa-nodulating strain, Sinorhizobium meliloti. Uninfected nodule-like structures developed on the soybean lectin-transgenic plant roots at very low inoculum concentrations, but bona fide infection threads were not detected even when B. japonicum produced the appropriate S. meliloti Nod factor. In contrast, the PSL-transgenic plants were not only well nodulated but also exhibited infection thread formation in response to R. leguminosarum bv viciae, but only when the bacteria expressed the complete set of S. meliloti nod genes. A few nodules from the PSL-transgenic plant roots were even found to be colonized by R. leguminosarum bv viciae expressing S. meliloti nod genes, but the plants were yellow and senescent, indicating that nitrogen fixation did not take place. Exopolysaccharide appears to be absolutely required for both nodule development and infection thread formation because neither occurred in PSL-transgenic plant roots following inoculation with an Exo(-) R. leguminosarum bv viciae strain that produced S. meliloti Nod factor. PMID:11351077

  3. Sugar-Binding Activity of Pea Lectin Enhances Heterologous Infection of Transgenic Alfalfa Plants by Rhizobium leguminosarum biovar viciae1

    PubMed Central

    van Rhijn, Pieternel; Fujishige, Nancy A.; Lim, Pyung Ok; Hirsch, Ann M.

    2001-01-01

    Transgenic alfalfa (Medicago sativa L. cv Regen) roots carrying genes encoding soybean lectin or pea (Pisum sativum) seed lectin (PSL) were inoculated with Bradyrhizobium japonicum or Rhizobium leguminosarum bv viciae, respectively, and their responses were compared with those of comparably inoculated control plants. We found that nodule-like structures formed on alfalfa roots only when the rhizobial strains produced Nod factor from the alfalfa-nodulating strain, Sinorhizobium meliloti. Uninfected nodule-like structures developed on the soybean lectin-transgenic plant roots at very low inoculum concentrations, but bona fide infection threads were not detected even when B. japonicum produced the appropriate S. meliloti Nod factor. In contrast, the PSL-transgenic plants were not only well nodulated but also exhibited infection thread formation in response to R. leguminosarum bv viciae, but only when the bacteria expressed the complete set of S. meliloti nod genes. A few nodules from the PSL-transgenic plant roots were even found to be colonized by R. leguminosarum bv viciae expressing S. meliloti nod genes, but the plants were yellow and senescent, indicating that nitrogen fixation did not take place. Exopolysaccharide appears to be absolutely required for both nodule development and infection thread formation because neither occurred in PSL-transgenic plant roots following inoculation with an Exo− R. leguminosarum bv viciae strain that produced S. meliloti Nod factor. PMID:11351077

  4. Assessment of Heat Shock Protein 70 Induction by Heat in Alfalfa Varieties and Constitutive Overexpression in Transgenic Plants

    PubMed Central

    Ferradini, Nicoletta; Iannacone, Rina; Capomaccio, Stefano; Metelli, Alessandra; Armentano, Nadia; Semeraro, Lucia; Cellini, Francesco; Veronesi, Fabio; Rosellini, Daniele

    2015-01-01

    Heat shock proteins (HSPs) are molecular chaperones involved in many cellular functions. It has been shown that mammalian cytosolic HSP70 binds antigenic peptides mediating the activation of the immune system, and that it plays a determining role in tumour immunogenicity. This suggests that HSP70 may be used for the production of conjugated vaccines. Human and plant HSPs share high sequence similarity and some important biological functions in vitro. In addition, plant HSPs have no endotoxic side effects. Extraction of HSP70 from plants for use as vaccine adjuvant requires enhancing its concentration in plant tissues. In this work, we explored the possibility to produce HSP70 in both transgenic and non-transgenic plants, using alfalfa as a model species. First, a transcriptional analysis of a constitutive and an inducible HSP70 genes was conducted in Arabidopsis thaliana. Then the coding sequence of the inducible form was cloned and introduced into alfalfa by Agrobacterium-mediated transformation, and the accumulation of the protein in leaf tissue of transgenic plants was demonstrated. We also tested diverse alfalfa varieties for heat-inducible expression of endogenous HSP70, revealing variety-specific responses to heat shock. PMID:25951604

  5. Evaluation of aluminum indices to predict aluminum toxicity to plants grown in nutrient solutions

    SciTech Connect

    Alva, A.K.; Blamey, F.P.C.; Edwards, D.G.; Asher, C.J.

    1986-01-01

    Difficulty has been experienced in establishing a suitable aluminum (Al) index to predict Al toxicity to plants grown in nutrient solutions with a wide range of properties. In the present study, relationships were evaluated between root length and (i) concentration of total Al, (ii) concentration of monomeric Al, and (iii) the sum of the activities of monomeric Al species (..sigma..a/sub Al mono/) in solution. Results are reported for soybean (Glycine max (L.) Merr.), subterranean clover (Trifolium subterraneum L.), alfalfa (Medicago sativa L.), and sunflower (Helianthus annuus L.). Total Al concentration in solution, comprising polymeric and monomeric Al species, was a poor index of Al toxicity, confirming the hypothesis that only monomeric Al is toxic to root growth. In solutions with widely differing composition, the concentration of monomeric Al also proved unsatisfactory due to ionic strength effects on the activities of monomeric Al species. ..sigma..a/sub Al mono/ was the best index of Al toxicity, accounting for 72 to 92% of the variation in root length depending on the plant species. Root length was reduced by 50% at ..sigma..a/sub Al mono/ of 7-16 ..mu..M in soybean, 13 ..mu..M in subterranean clover and alfalfa, and 11 ..mu..M in sunflower.

  6. Ractopamine uptake by alfalfa (Medicago sativa) and wheat (Triticum aestivum) from soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ractopamine is a beta adrenergic agonist used as a growth promoter in swine, cattle and turkeys. To test whether ractopamine has the potential to accumulate in plants grown in contaminated soil, a greenhouse study was conducted with alfalfa (Medicago sativa) and wheat (Triticum aestivum) grown in t...

  7. Water transfer in an alfalfa/maize association. [Medicago sativa; Zea mays

    SciTech Connect

    Corak, S.J.; Blevins, D.G.; Pallardy, S.G.

    1987-07-01

    The authors investigated the possibility of interspecific water transfer in an alfalfa (Medicago sativa L.) and maize (Zea mays L.) association. An alfalfa plant was grown through two vertically stacked plastic tubes. A 5 centimeter air gap between tubes was bridged by alfalfa roots. Five-week old maize plants with roots confined to the top tube were not watered, while associated alfalfa roots had free access to water in the bottom tube (the -/+ treatment). Additional treatments included: top and bottom tubes watered (+/+), top and bottom tubes droughted (-/-), and top tube droughted after removal of alfalfa root bridges and routine removal of alfalfa tillers (-*). Predawn leaf water potential of maize in the -/+ treatment fell to -1.5 megapascals 13 days after the start of drought; thereafter, predawn and midday potentials were maintained near -1.9 megapascals. Leaf water potentials of maize in the -/- and -* treatments declined steadily; all plants in these treatments were completely desiccated before day 50. High levels of tritium activity were detected in water extracted from both alfalfa and maize leaves after /sup 3/H/sub 2/O was injected into the bottom -/+ tube at day 70 or later. Maize in the -/+ treatment was able to survive an otherwise lethal period of drought by utilizing water lost by alfalfa roots.

  8. The elicitor-inducible alfalfa isoflavone reductase promoter confers different patterns of developmental expression in homologous and heterologous transgenic plants.

    PubMed Central

    Oommen, A; Dixon, R A; Paiva, N L

    1994-01-01

    In legumes, the synthesis of infection- and elicitor-inducible antimicrobial phytoalexins occurs via the isoflavonoid branch of the phenylpropanoid pathway. To study transcriptional regulation of isoflavonoid pathway-specific genes, we have isolated the gene encoding isoflavone reductase (IFR), which is the enzyme that catalyzes the penultimate step in the synthesis of the phytoalexin medicarpin in alfalfa. Chimeric gene fusions were constructed between 765- and 436-bp promoter fragments of the IFR gene and the beta-glucuronidase reporter gene and transferred to alfalfa and tobacco by Agrobacterium-mediated transformation. Both promoter fragments conferred elicitor-mediated expression in cell suspension cultures derived from transgenic plants of both species and fungal infection-mediated expression in leaves of transgenic alfalfa. Developmental expression directed by both promoter fragments in transgenic alfalfa was observed only in the root meristem, cortex, and nodules, which is consistent with the accumulation of endogenous IFR transcripts. However, in transgenic tobacco, expression from the 765-bp promoter was observed in vegetative tissues (root meristem and cortex, inner vascular tissue of stems and petioles, leaf tips, and stem peripheries adjacent to petioles) and in reproductive tissues (stigma, placenta, base of the ovary, receptacle, seed, tapetal layer, and pollen grains), whereas the 436-bp promoter was expressed only in fruits, seed, and pollen. These data indicate that infection/elicitor inducibility of the IFR promoter in both species and developmental expression in alfalfa are determined by sequences downstream of position -436, whereas sequences between -436 and -765 confer a complex pattern of strong ectopic developmental expression in the heterologous species that lacks the isoflavonoid pathway. PMID:7866024

  9. Leaf δ(15)N as a physiological indicator of the responsiveness of N2-fixing alfalfa plants to elevated [CO2], temperature and low water availability.

    PubMed

    Ariz, Idoia; Cruz, Cristina; Neves, Tomé; Irigoyen, Juan J; Garcia-Olaverri, Carmen; Nogués, Salvador; Aparicio-Tejo, Pedro M; Aranjuelo, Iker

    2015-01-01

    The natural (15)N/(14)N isotope composition (δ(15)N) of a tissue is a consequence of its N source and N physiological mechanisms in response to the environment. It could potentially be used as a tracer of N metabolism in plants under changing environmental conditions, where primary N metabolism may be complex, and losses and gains of N fluctuate over time. In order to test the utility of δ(15)N as an indicator of plant N status in N2-fixing plants grown under various environmental conditions, alfalfa (Medicago sativa L.) plants were subjected to distinct conditions of [CO2] (400 vs. 700 μmol mol(-1)), temperature (ambient vs. ambient +4°C) and water availability (fully watered vs. water deficiency-WD). As expected, increased [CO2] and temperature stimulated photosynthetic rates and plant growth, whereas these parameters were negatively affected by WD. The determination of δ(15)N in leaves, stems, roots, and nodules showed that leaves were the most representative organs of the plant response to increased [CO2] and WD. Depletion of heavier N isotopes in plants grown under higher [CO2] and WD conditions reflected decreased transpiration rates, but could also be related to a higher N demand in leaves, as suggested by the decreased leaf N and total soluble protein (TSP) contents detected at 700 μmol mol(-1) [CO2] and WD conditions. In summary, leaf δ(15)N provides relevant information integrating parameters which condition plant responsiveness (e.g., photosynthesis, TSP, N demand, and water transpiration) to environmental conditions. PMID:26322051

  10. Leaf δ15N as a physiological indicator of the responsiveness of N2-fixing alfalfa plants to elevated [CO2], temperature and low water availability

    PubMed Central

    Ariz, Idoia; Cruz, Cristina; Neves, Tomé; Irigoyen, Juan J.; Garcia-Olaverri, Carmen; Nogués, Salvador; Aparicio-Tejo, Pedro M.; Aranjuelo, Iker

    2015-01-01

    The natural 15N/14N isotope composition (δ15N) of a tissue is a consequence of its N source and N physiological mechanisms in response to the environment. It could potentially be used as a tracer of N metabolism in plants under changing environmental conditions, where primary N metabolism may be complex, and losses and gains of N fluctuate over time. In order to test the utility of δ15N as an indicator of plant N status in N2-fixing plants grown under various environmental conditions, alfalfa (Medicago sativa L.) plants were subjected to distinct conditions of [CO2] (400 vs. 700 μmol mol−1), temperature (ambient vs. ambient +4°C) and water availability (fully watered vs. water deficiency—WD). As expected, increased [CO2] and temperature stimulated photosynthetic rates and plant growth, whereas these parameters were negatively affected by WD. The determination of δ15N in leaves, stems, roots, and nodules showed that leaves were the most representative organs of the plant response to increased [CO2] and WD. Depletion of heavier N isotopes in plants grown under higher [CO2] and WD conditions reflected decreased transpiration rates, but could also be related to a higher N demand in leaves, as suggested by the decreased leaf N and total soluble protein (TSP) contents detected at 700 μmol mol−1 [CO2] and WD conditions. In summary, leaf δ15N provides relevant information integrating parameters which condition plant responsiveness (e.g., photosynthesis, TSP, N demand, and water transpiration) to environmental conditions. PMID:26322051

  11. Control of western tarnished plant bug Lygus hesperus Knight (Hemiptera: Miridae) in California organic strawberries using alfalfa trap crops and tractor-mounted vacuums.

    PubMed

    Swezey, Sean L; Nieto, Diego J; Bryer, Janet A

    2007-12-01

    A key economic pest of strawberries in California is the western tarnished plant bug, Lygus hesperus Knight (Hemiptera:Miridae). Alfalfa (Medicago sativa L.) is a highly attractive plant host to western tarnished plant bug, and we hypothesized that it can be successfully managed as a trap crop for pest suppression in strawberries. Completely randomized design trap cropping experiments were established on an organic strawberry farm from 2002 to 2004. Western tarnished plant bug adults and nymphs were significantly more abundant in alfalfa trap crops than in comparable edge strawberry rows. Over 3 experimental yr, twice-weekly summer vacuuming of alfalfa trap crops with a tractor-mounted vacuuming device reduced adult and nymph abundance by 72 and 90%, respectively, in trap crops. This summer vacuuming of alfalfa trap crops also significantly reduced damage caused by western tarnished plant bug in associated unvacuumed organic strawberries (June and July 2002, June 2003, and June and July 2004) compared with either an untreated control (2003) or the organic strawberry grower's standard whole field vacuuming treatment. Vacuuming of alfalfa trap crops reduces an organic grower's costs (tractor, tractor fuel, and driver time) by 78% compared with current whole field vacuuming practices. An economic analysis of a whole hectare model indicates that a positive return from the use of vacuumed trap crops could be realized in 2004. The overall potential positive net return for the 3 mo of vacuumed alfalfa trap crop treatments in 2004 was calculated at +$1,829/ha. PMID:18284774

  12. A multistate outbreak of Escherichia coli O157:H7 infections linked to alfalfa sprouts grown from contaminated seeds.

    PubMed Central

    Breuer, T.; Benkel, D. H.; Shapiro, R. L.; Hall, W. N.; Winnett, M. M.; Linn, M. J.; Neimann, J.; Barrett, T. J.; Dietrich, S.; Downes, F. P.; Toney, D. M.; Pearson, J. L.; Rolka, H.; Slutsker, L.; Griffin, P. M.

    2001-01-01

    A multistate outbreak of Escherichia coli O157:H7 infections occurred in the United States in June and July 1997. Two concurrent outbreaks were investigated through independent case-control studies in Michigan and Virginia and by subtyping isolates with pulsed-field gel electrophoresis (PFGE). Isolates from 85 persons were indistinguishable by PFGE. Alfalfa sprouts were the only exposure associated with E. coli O157:H7 infection in both Michigan and Virginia. Seeds used for sprouting were traced back to one common lot harvested in Idaho. New subtyping tools such as PFGE used in this investigation are essential to link isolated infections to a single outbreak. PMID:11747724

  13. Experimental and modeling studies of the fate of organic contaminants in the presence of alfalfa plants

    SciTech Connect

    Muralidharan, N.; Davis, L.C.; Erickson, L.E.; Green, R.; Tracy, J.C.

    1994-12-31

    Experimental investigations were carried out in the laboratory to study the impact of vegetation in bioremediating soil and groundwater contaminated with hazardous organic substances. A 90 cm long chamber with 2 U-shaped channels, each 10 cm in width and 35 cm in depth, was set up. Alfalfa plants were chosen and they have been growing in the channels under laboratory conditions for nearly 2 years. The channels were packed with fine sandy soil collected from near a landfill. The groundwater fed to one channel was water contaminated with toluene solution at saturated concentrations {at} 25 C, whereas, the other channel was fed with water contaminated with phenol solution {at} 500 ppm (v/v). The contaminant concentrations in the groundwater of the channels were monitored at the sampling wells located along each of the channels. The influent and effluent flow rates from each channel were measured every day and recorded. Evapotranspiration significantly influenced the fate of the pollutants. Dispersion and adsorption processes in the channel were studied by introducing bromide tracer, as a broad pulse, into the toluene fed channel and by observing toluene and phenol concentrations, following a feed step change to pure water. Tracer studies indicated that short-circuiting in the end of the channel was quite significant. Models which were previously developed to describe the fate of the contaminants in variably-saturated soils in the presence of vegetation are being employed to simulate the fate of these hazardous organic substances in the laboratory chamber.

  14. Liquid chromatography-tandem mass spectrometry method for the determination of anthelmintics in alfalfa plants.

    PubMed

    Islam, M Dabalus; Haberhauer, G; Gerzabek, M; Cannavan, A

    2012-01-01

    A simple and inexpensive liquid chromatography-tandem mass spectrometric method for the determination of anthelmintics in alfalfa plants (Medicago sativa L.) was developed and validated. Anthelmintics in plant leaves and stems (green chops) were extracted with methanol/acetonitrile (7:3, v/v) followed by a concentration and clean-up step using solid-phase extraction (Strata-X, 500 mg, 6 ml cartridge). After drying with nitrogen gas, the adsorbed analytes were eluted with methanol/acetonitrile (50:50, v/v) mixture followed by 100% acetonitrile. Chromatographic separation was achieved on an Atlantis T-3 (2.1 × 100 mm × 3 µm) analytical column with a Phenomenex guard cartridge (C8, 4 × 3 mm) attached to a Waters triple quadrupole mass spectrometer operated in positive electrospray ionisation mode with selected reaction monitoring. Samples were analysed using gradient elution at a flow rate of 0.35 ml min⁻¹. The mobile phase consisted of a 10 mM ammonium formate solution in (A) water/acetonitrile (90:10, v/v) and (B) methanol/acetonitrile (50:50, v/v). The method was validated for levamisole, fenbendazole, fenbendazole sulphoxide and fenbendazole sulphone at 10, 20 and 40 µg kg⁻¹ and for eprinomectin at 20, 40 and 80 µg kg⁻¹. Limits of quantification (LOQ) were 10 µg kg⁻¹ for all analytes except eprinomectin, which had an LOQ of 20 µg kg⁻¹. The overall mean recovery in green plants was between 74.2% and 81.4% with repeatabilities ranging from 2.2% to 19.1% and reproducibilities in the range 3.8-8.7%. The validated method was applied to plant samples in a study on the behaviour of anthelmintic drugs in a soil, plant and water system. PMID:22827314

  15. Progress report on reduced-lignin alfalfa: part 1, plant modifications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is the most important forage legume in U.S. dairy cow diets because it has a high protein content, it increases feed intake and milk production, and it is an excellent complement to non-forage components of dairy cow diets. It is also an excellent source of effective fiber which is essential...

  16. Weed management research in alfalfa seed production in Washington state

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control is an important component of producing high quality and high yielding alfalfa seed. Alfalfa seed is produced with wider row and lower plant populations than alfalfa forage requiring greater weed management inputs. Flumioxazin was evaluated for weed control in alfalfa seed and forage pro...

  17. GENETIC MAPPING FORAGE YIELD, PLANT HEIGHT, AND REGROWTH AT MULTIPLE HARVESTS IN TETRAPLOID ALFALFA (MEDICAGO SATIVA L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crosses between Medicago sativa subspecies falcata and sativa result in high levels of heterosis for alfalfa forage production. However, desirable alfalfa cultivars must have acceptable performance for other agronomic traits including regrowth following harvest and appropriate autumn dormancy. In ...

  18. Growth and photosynthetic responses of wheat plants grown in space

    NASA Technical Reports Server (NTRS)

    Tripathy, B. C.; Brown, C. S.; Levine, H. G.; Krikorian, A. D.

    1996-01-01

    Growth and photosynthesis of wheat (Triticum aestivum L. cv Super Dwarf) plants grown onboard the space shuttle Discovery for 10 d were examined. Compared to ground control plants, the shoot fresh weight of space-grown seedlings decreased by 25%. Postflight measurements of the O2 evolution/photosynthetic photon flux density response curves of leaf samples revealed that the CO2-saturated photosynthetic rate at saturating light intensities in space-grown plants declined 25% relative to the rate in ground control plants. The relative quantum yield of CO2-saturated photosynthetic O2 evolution measured at limiting light intensities was not significantly affected. In space-grown plants, the light compensation point of the leaves increased by 33%, which likely was due to an increase (27%) in leaf dark-respiration rates. Related experiments with thylakoids isolated from space-grown plants showed that the light-saturated photosynthetic electron transport rate from H2O through photosystems II and I was reduced by 28%. These results demonstrate that photosynthetic functions are affected by the microgravity environment.

  19. Biotechnological advancements in alfalfa improvement.

    PubMed

    Kumar, Suresh

    2011-05-01

    Review of biotechnology research in alfalfa shows that molecular techniques are extensively being used for basic and applied research toward alfalfa improvement. Biotechnological approaches have been used in two major areas, genomics and transgenics. In genomics, molecular markers, structural and functional genomics allowed identification of genes of interest and their regulatory components. Alfalfa being obstinate to genetic and genomic analysis, comparative genomics is used for molecular and genetic dissection of various plant processes in alfalfa. Alternatively, transgenic approach involves incorporation of specific and useful genes into alfalfa to improve the traits of interest. Input traits to improve agronomic performance and output traits to improve forage quality, or to produce novel industrial/pharmaceutical proteins, are the focus of current transgenic research in alfalfa. However, transgenic approach is controversial requiring cautious experimental design to combat bioisafety concerns. Ideally, forage alfalfa needs to possess more fermentable carbohydrates, proteins with balanced amino acid profile that degrade slower in rumen, improved winter hardiness, better water use efficiency, pest resistance and no anti-quality factors. Concerted efforts are required to bring together maximum of these characteristic features into the alfalfa plant. PMID:21279557

  20. Effects of nitrogen source and water availability on stem carbohydrates and cellulosic bioethanol traits of alfalfa plants.

    PubMed

    Fiasconaro, M Laura; Gogorcena, Yolanda; Muñoz, Fernando; Andueza, Donato; Sánchez-Díaz, Manuel; Antolín, M Carmen

    2012-08-01

    Symbiotic association of legumes with rhizobia frequently results in higher photosynthesis and soluble carbohydrates in comparison with nitrate-fed plants, which might improve its potential for biomass conversion into bioethanol. A greenhouse experiment was conducted to examine the effects of nitrogen source and water availability on stem characteristics and on relationships between carbohydrates, phenolic metabolism activity and cell wall composition in alfalfa (Medicago sativa L. cv. Aragón). The experiment included three treatments: (1) plants fed with ammonium nitrate (AN); (2) plants inoculated with rhizobia (R); and (3) plants inoculated with rhizobia and amended with sewage sludge (RS). Two levels of irrigation were imposed: (1) well-watered and (2) drought stress. Under well-watered conditions, nitrogen-fixing plants have increased photosynthesis and stem fermentable carbohydrate concentrations, which result in higher potential for biomass conversion to bioethanol than in AN plants. The latter had higher lignin due to enhanced activities of phenolic metabolism-related enzymes. Under drought conditions, the potential for bioethanol conversion decreased to a similar level in all treatments. Drought-stressed nitrogen-fixing plants have high concentrations of fermentable carbohydrates and cell wall cellulose, but ammonium nitrate-fed plants produced higher plant and stem biomass, which might compensate the decreasing stem carbohydrates and cellulose concentrations. PMID:22682561

  1. Scientists Inspect Plant Grown onboard the ISS in 2002

    NASA Technical Reports Server (NTRS)

    2003-01-01

    The Advanced Astroculture (tm) unit is growing plants on its second flight on the International Space Station. Dr. Weijia Zhou (left), director of the Wisconsin Center for Space Automation and Robotics at the University of Wisconsin-Madison, inspects soybeans grown in the plant growth unit aboard ISS in 2002. Coating technology is used inside the miniature plant greenhouse to remove ethylene, a chemical produced by plant leaves that can cause plants to mature too quickly. This same coating technology is used in a new anthrax-killing device. The Space Station experiment is managed by the Space Partnership Development Program at NASA's Marshall Space Flight Center in Huntsville, Ala.

  2. Influence of Mount St. Helens volcanic ash on alfalfa growth and nutrient uptake

    SciTech Connect

    Mahler, R.L.

    1984-01-01

    Concern has been expressed that large amounts of volcanic ash from the May 18, 1980 eruption of Mount St. Helens may have created potential nutritional problems associated with forage production in northern Idaho and eastern Washington to the extent that adjustments need to be made in soil test correlation data. The objectives of this greenhouse study were to : (1) determine the effect of varying amounts of volcanic ash mixed into soils of northern Idaho on total alfalfa biomass production, and (2) to determine the effect of various soil/ash mixtures on the nutrient concentrations of P, K, S, Ca, Mg, Mn and Zn in alfalfa. Alfalfa was grown in eight different northern Idaho soils amended with differing levels of volcanic ash (0, 20, 35, 50 and 75%) in the greenhouse. The alfalfa seeds were inoculated and fertilizer P and S were added to all treatments. Total plant biomass and P, K, S, Ca, Mg, Mn and Zn plant concentrations were measured. The eight were pooled for analysis and it was found that increasing amounts of volcanic ash increased alfalfa biomass production. Plant P, S, Ca, Mg and Zn concentrations also increased with increasing levels of ash. Conversely, increasing levels of ash resulted in lower alfalfa tissue K and Mn concentrations. 13 references, 7 figures.

  3. Glycolytic Flux Is Adjusted to Nitrogenase Activity in Nodules of Detopped and Argon-Treated Alfalfa Plants1

    PubMed Central

    Curioni, Paola M.G.; Hartwig, Ueli A.; Nösberger, Josef; Schuller, Kathryn A.

    1999-01-01

    To investigate the short-term (30–240 min) interactions among nitrogenase activity, NH4+ assimilation, and plant glycolysis, we measured the concentrations of selected C and N metabolites in alfalfa (Medicago sativa L.) root nodules after detopping and during continuous exposure of the nodulated roots to Ar:O2 (80:20, v/v). Both treatments caused an increase in the ratios of glucose-6-phosphate to fructose-1,6-bisphosphate, fructose-6-phosphate to fructose-1,6-bisphosphate, phosphoenolpyruvate (PEP) to pyruvate, and PEP to malate. This suggested that glycolytic flux was inhibited at the steps catalyzed by phosphofructokinase, pyruvate kinase, and PEP carboxylase. In the Ar:O2-treated plants the apparent inhibition of glycolytic flux was reversible, whereas in the detopped plants it was not. In both groups of plants the apparent inhibition of glycolytic flux was delayed relative to the decline in nitrogenase activity. The decline in nitrogenase activity was followed by a dramatic increase in the nodular glutamate to glutamine ratio. In the detopped plants this was coincident with the apparent inhibition of glycolytic flux, whereas in the Ar:O2-treated plants it preceded the apparent inhibition of glycolytic flux. We propose that the increase in the nodular glutamate to glutamine ratio, which occurs as a result of the decline in nitrogenase activity, may act as a signal to decrease plant glycolytic flux in legume root nodules. PMID:9952439

  4. Integrated protein production and electricity generation using renewable alfalfa feedstock in a combination advanced IGCC and feed processing arrangement

    SciTech Connect

    DeLong, M.M.; Oelke, E.A.; Hanson, C.

    1999-07-01

    A feasibility study was conducted to determine the viability of a co-production concept of alfalfa leaf meal as a concentrated protein animal feed and the generation of electricity from the remaining stem material. Alfalfa is a well-known and widely-planted crop that offers environmental and soil conservation advantages when grown as a 4-year segment in a 7-year rotation with corn and soybeans. Alfalfa fixes nitrogen from the air, thereby enhancing soil nitrogen and decreasing the need for manufactured nitrogen fertilizer. With alfalfa yields of 8.96 metric tonnes/hectare (4 dry tons per acre) per year and with separated alfalfa leaves being sold as a high-value animal feed, separated alfalfa stems can be economically viable fuel feedstock for a gasifier/combined cycle power plant. This paper reports on a feasibility study for an integrated biomass power system, where an energy crop (alfalfa) is coupled to a processing plant and a power plant (integrated gasification combined cycle with hot gas cleanup) in a way that benefits the joint venture of an alfalfa producers cooperative and a utility entity. The sale of a mid-level protein animal feed-co-product and electricity both support the production cost of alfalfa. The co-product/fuel processing operation uses a common train of equipment, thereby requiring neither product to carry the total cost. The power plant provides an important continuous demand for the feedstock and results in continuous supply of leaf product to provide a reliable supply needed for the leaf meal product. This concept provides a means for rural economic development with a sustainable approach to production agriculture.

  5. PLUTONIUM UPTAKE BY PLANTS GROWN IN SOLUTION CULTURE

    EPA Science Inventory

    Plants grown in aquatic systems were shown to rapidly accumulate large amounts of plutonium, about 40% of which was removed by washing. Detergent removed debris, most of which consisted of particles larger than 0.8 micrometers. After removing a portion of the bound Pu by rinsing ...

  6. Accumulation of seleno-amino acids in legume and grass plant species grown in selenium-laden soils

    SciTech Connect

    Wu, L.; Guo, X.; Banuelos, G.S.

    1997-03-01

    Seleno-amino acid accumulation was studied for two legume and two grass species grown in Selenium (Se)-laden soils. An antagonistic relationship was found between the tissue Se-amino acid concentration and the corresponding sulfur-amino acid concentration. This relationship demonstrates a competitive interaction between Se and sulfate at the amino acid synthesis level. The nonsulfur-containing amino acids were not substantially affected by the increase of tissue Se concentration. Sour clover (Melilotus indica L.) was able to accumulate much greater tissue Se concentration than the other three species. Tissue methionine concentration of sour clover, rabbitfoot grass (Polypogon monspeliensis L.), and tall fescue (Festuca arundinacea Schreb.) was not significantly affected by the increase of tissue selenomethionine concentration, but a highly significant negative correlation was found in alfalfa (Medicago sativa L.). This discrepancy suggests that a less antagonistic effect on sulfur-amino acids under the increase of Se-amino acid analogues in the tissue might be able to minimize Se toxicity to the plant. Both Se-methylselenocysteine (nonprotein amino acid) and selenomethionine (protein amino acid) accumulated in the plants when grown in Se-laden soils. Possible effects of these Se-amino acids accumulated by plants on animal health should be tested before the plants are used for forage supplementation.

  7. Specific mechanisms of tolerance to copper and cadmium are compromised by a limited concentration of glutathione in alfalfa plants.

    PubMed

    Flores-Cáceres, María Laura; Hattab, Sabrine; Hattab, Sarra; Boussetta, Hamadi; Banni, Mohammed; Hernández, Luis E

    2015-04-01

    The induction of oxidative stress is a characteristic symptom of metal phytotoxicity and is counteracted by antioxidants such as glutathione (GSH) or homoglutathione (hGSH). The depletion of GSH│hGSH in fifteen-day-old alfalfa (Medicago sativa) plants pre-incubated with 1mM buthionine sulfoximine (BSO) affected antioxidant responses in a metal-specific manner under exposure to copper (Cu; 0, 6, 30 and 100μM) or cadmium (Cd; 0, 6 and 30μM) for 7 days. The phytotoxic symptoms observed with excess Cu were accompanied by an inhibition of root glutathione reductase (GR) activity, a response that was augmented in Cd-treated plants but reverted when combined with BSO. The synthesis of phytochelatins (PCs) was induced by Cd, whereas the biothiol concentration decreased in Cu-treated plants, which did not accumulate PCs. The depletion of GSH│hGSH by BSO also produced a strong induction of oxidative stress under excess Cu stress, primarily due to impaired GSH│hGSH-dependent redox homeostasis. In addition, the synthesis of PCs was required for Cd detoxification, apparently also determining the distribution of Cd in plants, as less metal was translocated to the shoots in BSO-incubated plants. Therefore, specific GSH│hGSH-associated mechanisms of tolerance were triggered by stress due to each metal. PMID:25711824

  8. Soluble methionine enhances accumulation of a 15 kDa zein, a methionine-rich storage protein, in transgenic alfalfa but not in transgenic tobacco plants.

    PubMed

    Amira, Golan; Ifat, Matityahu; Tal, Avraham; Hana, Badani; Shmuel, Galili; Rachel, Amir

    2005-09-01

    With the general aim of elevating the content of the essential amino acid methionine in vegetative tissues of plants, alfalfa (Medicago sativa L.) and tobacco plants, as well as BY2 tobacco suspension cells, were transformed with a beta-zein::3HA gene under the 35S promoter of cauliflower mosaic virus encoding a rumen-stable methionine-rich storage protein of 15 kDa zein. To examine whether soluble methionine content limited the accumulation of the 15 kDa zein::3HA, methionine was first added to the growth medium of the different transgenic plants and the level of the alien protein was determined. Results demonstrated that the added methionine enhanced the accumulation of the 15 kDa zein::3HA in transgenic alfalfa and tobacco BY2 cells, but not in whole transgenic tobacco plants. Next, the endogenous levels of methionine were elevated in the transgenic tobacco and alfalfa plants by crossing them with plants expressing the Arabidopsis cystathionine gamma-synthase (AtCGS) having significantly higher levels of soluble methionine in their leaves. Compared with plants expressing only the 15 kDa zein::3HA, transgenic alfalfa co-expressing both alien genes showed significantly enhanced levels of this protein concurrently with a reduction in the soluble methionine content, thus implying that soluble methionine was incorporated into the 15 kDa zein::3HA. Similar phenomena also occurred in tobacco, but were considerably less pronounced. The results demonstrate that the accumulation of the 15 kDa zein::3HA is regulated in a species-specific manner and that soluble methionine plays a major role in the accumulation of the 15 kDa zein in some plant species but less so in others. PMID:16061510

  9. Cogeneration for existing alfalfa processing

    SciTech Connect

    Not Available

    1984-01-01

    This study is designed to look at the application of gas-turbine generator cogeneration to a typical Nebraska alfalfa processing mill. The practicality is examined of installing a combustion turbine generator at a plant site and modifying existing facilities for generating electricity, utilizing the electricity generated, selling excess electricity to the power company and incorporating the turbine exhaust flow as a drying medium for the alfalfa. The results of this study are not conclusive but the findings are summarized.

  10. Plant response to heavy metal toxicity: comparative study between the hyperaccumulator Thlaspi caerulescens (ecotype Ganges) and nonaccumulator plants: lettuce, radish, and alfalfa.

    PubMed

    Benzarti, Saoussen; Mohri, Shino; Ono, Yoshiro

    2008-10-01

    Thlaspi caerulescens (alpine pennycress) is one of the best-known heavy metal (HM) hyperaccumulating plant species. It exhibits the ability to extract and accumulate various HM at extremely high concentrations. In this hydroponic study, the performance of T. caerulescens (ecotype Ganges) to accumulate Cd, Zn, and Cu was compared with that of three nonaccumulator plants: alfalfa (Medicago sativa), radish (Raphanus sativus), and lettuce (Lactuca sativa). Plants were exposed to the separately dissolved HM salts for 7 days at a wide range of increasing concentrations: 0 (control: 1/5 Hoagland nutrient solution), 0.1, 1, 10, 100, and 1000 microM. The comparative study combined chemical, physiological, and ecotoxicological assessments. Excessive concentrations of HM (100 and 1000 microM) affected plant growth, photosynthesis, and phytoaccumulation efficiency. Root exudation for all plant species was highly and significantly correlated to HM concentration in exposure solutions and proved its importance to counter effect toxicity. T. caerulescens resisted better the phytotoxic effects of Cd and Zn (at 1000 microM each), and translocated them significantly within tissues (366 and 1290 microg g(-1), respectively). At the same HM level, T. caerulescens exhibited lower performances in accumulating Cu when compared with the rest of plant species, mainly alfalfa (298 microg g(-1)). Root elongation inhibition test confirmed the selective aptitude of T. caerulescens to better cope with Cd and Zn toxicities. MetPLATE bioassay showed greater sensitivity to HM toxicity with much lower EC(50) values for beta-galactosidase activity in E. coli. Nevertheless, exaggerated HM concentrations coupled with relatively short exposure time did not allow for an efficient metal phytoextraction thus a significant reduction of ecotoxicity. PMID:18528911

  11. Plant density and maturity stage impacts on stem cell wall composition in high quality and non-lodging alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concentration of stem cell wall constituents in alfalfa (Medicago sativa L.) can affect energy availability in livestock production systems and energy conversion efficiency when alfalfa is used to produce biofuels. Knowledge of the environmental variability of cell wall concentration and composi...

  12. [Determination of Hard Rate of Alfalfa (Medicago sativa L.) Seeds with Near Infrared Spectroscopy].

    PubMed

    Wang, Xin-xun; Chen, Ling-ling; Zhang, Yun-wei; Mao, Pei-sheng

    2016-03-01

    Alfalfa (Medicago sativa L.) is the most commonly grown forage crop due to its better quality characteristics and high adaptability in China. However, there was 20%-80% hard seeds in alfalfa which could not be identified easily from non hard seeds which would cause the loss of seed utilization value and plant production. This experiment was designed for 121 samples of alfalfa. Seeds were collected according to different regions, harvested year and varieties. 31 samples were artificial matched as hard rates ranging from 20% to 80% to establish a model for hard seed rate by near infrared spectroscopy (NIRS) with Partial Least Square (PLS). The objective of this study was to establish a model and to estimate the efficiency of NIRS for determining hard rate of alfalfa seeds. The results showed that the correlation coefficient (R2(cal)) of calibration model was 0.981 6, root mean square error of cross validation (RMSECV) was 5.32, and the ratio of prediction to deviation (RPD) was 3.58. The forecast model in this experiment presented the satisfied precision. The proposed method using NIRS technology is feasible for identification and classification of hard seed in alfalfa. A new method, as nondestructive testing of hard seed rate, was provided to theoretical basis for fast nondestructive detection of hard seed rates in alfalfa. PMID:27400509

  13. Functional Characterizations of Chemosensory Proteins of the Alfalfa Plant Bug Adelphocoris lineolatus Indicate Their Involvement in Host Recognition

    PubMed Central

    Zhang, Xue-Ying; Ji, Ping; Liu, Jing-Tao; Wang, Gui-Rong; Wu, Kong-Ming; Guo, Yu-Yuan; Zhou, Jing-Jiang; Zhang, Yong-Jun

    2012-01-01

    Insect chemosensory proteins (CSPs) have been proposed to capture and transport hydrophobic chemicals from air to olfactory receptors in the lymph of antennal chemosensilla. They may represent a new class of soluble carrier protein involved in insect chemoreception. However, their specific functional roles in insect chemoreception have not been fully elucidated. In this study, we report for the first time three novel CSP genes (AlinCSP1-3) of the alfalfa plant bug Adelphocoris lineolatus (Goeze) by screening the antennal cDNA library. The qRT-PCR examinations of the transcript levels revealed that all three genes (AlinCSP1-3) are mainly expressed in the antennae. Interestingly, these CSP genes AlinCSP1-3 are also highly expressed in the 5th instar nymphs, suggesting a proposed function of these CSP proteins (AlinCSP1-3) in the olfactory reception and in maintaining particular life activities into the adult stage. Using bacterial expression system, the three CSP proteins were expressed and purified. For the first time we characterized the types of sensilla in the antennae of the plant bug using scanning electron microscopy (SEM). Immunocytochemistry analysis indicated that the CSP proteins were expressed in the pheromone-sensitive sensilla trichodea and general odorant-sensitive sensilla basiconica, providing further evidence of their involvement in chemoreception. The antennal activity of 55 host-related semiochemicals and sex pheromone compounds in the host location and mate selection behavior of A. lineolatus was investigated using electroantennogram (EAG), and the binding affinities of these chemicals to the three CSPs (AlinCSP1-3) were measured using fluorescent binding assays. The results showed several host-related semiochemicals, (Z)-3-hexen-1-ol, (E)-2-hexen-1-al and valeraldehyde, have a high binding affinity with AlinCSP1-3 and can elicit significant high EAG responses of A. lineolatus antennae. Our studies indicate the three antennae-biased CSPs may

  14. Functional characterizations of chemosensory proteins of the alfalfa plant bug Adelphocoris lineolatus indicate their involvement in host recognition.

    PubMed

    Gu, Shao-Hua; Wang, Song-Ying; Zhang, Xue-Ying; Ji, Ping; Liu, Jing-Tao; Wang, Gui-Rong; Wu, Kong-Ming; Guo, Yu-Yuan; Zhou, Jing-Jiang; Zhang, Yong-Jun

    2012-01-01

    Insect chemosensory proteins (CSPs) have been proposed to capture and transport hydrophobic chemicals from air to olfactory receptors in the lymph of antennal chemosensilla. They may represent a new class of soluble carrier protein involved in insect chemoreception. However, their specific functional roles in insect chemoreception have not been fully elucidated. In this study, we report for the first time three novel CSP genes (AlinCSP1-3) of the alfalfa plant bug Adelphocoris lineolatus (Goeze) by screening the antennal cDNA library. The qRT-PCR examinations of the transcript levels revealed that all three genes (AlinCSP1-3) are mainly expressed in the antennae. Interestingly, these CSP genes AlinCSP1-3 are also highly expressed in the 5(th) instar nymphs, suggesting a proposed function of these CSP proteins (AlinCSP1-3) in the olfactory reception and in maintaining particular life activities into the adult stage. Using bacterial expression system, the three CSP proteins were expressed and purified. For the first time we characterized the types of sensilla in the antennae of the plant bug using scanning electron microscopy (SEM). Immunocytochemistry analysis indicated that the CSP proteins were expressed in the pheromone-sensitive sensilla trichodea and general odorant-sensitive sensilla basiconica, providing further evidence of their involvement in chemoreception. The antennal activity of 55 host-related semiochemicals and sex pheromone compounds in the host location and mate selection behavior of A. lineolatus was investigated using electroantennogram (EAG), and the binding affinities of these chemicals to the three CSPs (AlinCSP1-3) were measured using fluorescent binding assays. The results showed several host-related semiochemicals, (Z)-3-hexen-1-ol, (E)-2-hexen-1-al and valeraldehyde, have a high binding affinity with AlinCSP1-3 and can elicit significant high EAG responses of A. lineolatus antennae. Our studies indicate the three antennae-biased CSPs may

  15. [Growth and polysaccharide formation in Sinorhizobium meliloti strains in an air-lift-type fermentor. Effect on nodulation velocity in alfalfa plants].

    PubMed

    Lorda, G S; Castaño, R C; Pordomingo, A B; Pastor, M D; Balatti, A P

    2003-01-01

    In this paper the influence of the exopolysaccharides produced by Sinorhizobium meliloti strains on the nodulation rates in alfalfa plants has been considered. The experiments were performed in a rotary shaker and in an air-lift type fermentor. Different Sinorhizobium meliloti strains were used. Bacterial growth rates were determined by viable cell counts. Exopolysaccharide concentration was determined by precipitation with ethanol. It was observed that maximum cell concentration was in the order of 1 x 10(10) cell/ml and exopolysaccharide content was approximately 11 g/l. The experiments performed with alfalfa plants in a controlled environment chamber showed that, when inoculation was carried out with diluted suspensions (1/10), nodulation time was reduced from 10 to 4 days, while the strains retained their symbiotic properties. PMID:12920984

  16. Novel Use of Alfalfa Leafcutting Bees (Megachile rotundata) for Plant Genetic Resource Conservation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The North Central Regional Plant Introduction Station (NCRPIS) located in Ames, Iowa maintains a large collection of diverse plant germplasm. Controlled pollination of individual accessions is necessary to preserve the original genetic diversity. Some plants, especially those with conspicuous flowe...

  17. Complete genome sequence and integrated protein localization and interaction map for alfalfa dwarf virus, which combines properties of both cytoplasmic and nuclear plant rhabdoviruses

    SciTech Connect

    Bejerman, Nicolás; Giolitti, Fabián; Breuil, Soledad de; Trucco, Verónica; Nome, Claudia; Lenardon, Sergio; Dietzgen, Ralf G.

    2015-09-15

    Summary: We have determined the full-length 14,491-nucleotide genome sequence of a new plant rhabdovirus, alfalfa dwarf virus (ADV). Seven open reading frames (ORFs) were identified in the antigenomic orientation of the negative-sense, single-stranded viral RNA, in the order 3′-N-P-P3-M-G-P6-L-5′. The ORFs are separated by conserved intergenic regions and the genome coding region is flanked by complementary 3′ leader and 5′ trailer sequences. Phylogenetic analysis of the nucleoprotein amino acid sequence indicated that this alfalfa-infecting rhabdovirus is related to viruses in the genus Cytorhabdovirus. When transiently expressed as GFP fusions in Nicotiana benthamiana leaves, most ADV proteins accumulated in the cell periphery, but unexpectedly P protein was localized exclusively in the nucleus. ADV P protein was shown to have a homotypic, and heterotypic nuclear interactions with N, P3 and M proteins by bimolecular fluorescence complementation. ADV appears unique in that it combines properties of both cytoplasmic and nuclear plant rhabdoviruses. - Highlights: • The complete genome of alfalfa dwarf virus is obtained. • An integrated localization and interaction map for ADV is determined. • ADV has a genome sequence similarity and evolutionary links with cytorhabdoviruses. • ADV protein localization and interaction data show an association with the nucleus. • ADV combines properties of both cytoplasmic and nuclear plant rhabdoviruses.

  18. Uptake of human pharmaceuticals by plants grown under hydroponic conditions.

    PubMed

    Herklotz, Patrick A; Gurung, Prakash; Vanden Heuvel, Brian; Kinney, Chad A

    2010-03-01

    Cabbage (Brassica rapa var. pekinensis) and Wisconsin Fast Plants (Brassica rapa) were chosen for a proof of concept study to determine the potential uptake and accumulation of human pharmaceuticals by plants. These plants were grown hydroponically under high-pressure sodium lamps in one of two groups including a control and test group exposed to pharmaceuticals. The control plants were irrigated with a recirculating Hoagland's nutrient solution while the test plants were irrigated with a Hoagland's nutrient solution fortified with the pharmaceuticals carbamazepine, salbutamol, sulfamethoxazole, and trimethoprim at 232.5 microg L(-1). When plants reached maturity, nine entire plants of each species were separated into components such as roots, leaves, stems, and seedpods where applicable. An analytical method for quantifying pharmaceuticals and personal care products was developed using pressurized liquid extraction and liquid chromatography electrospray ionization mass spectrometry (LC/ESI/MS) in positive and negative ion modes using single ion monitoring. The method detection limits ranged from 3.13 ng g(-1) to 29.78 ng g(-1) with recoveries ranging from 66.83% to 113.62% from plant matrices. All four of the pharmaceuticals were detected in the roots and leaves of the cabbage. The maximum wet weight concentrations of the pharmaceuticals were detected in the root structure of the cabbage plants at 98.87 ng g(-1) carbamazepine, 114.72 ng g(-1) salbutamol, 138.26 ng g(-1) sulfamethoxazole, and 91.33 ng g(-1) trimethoprim. Carbamazepine and salbutamol were detected in the seedpods of the Wisconsin Fast Plants while all four of the pharmaceuticals were detected in the leaf/stem/root of the Wisconsin Fast Plants. Phloroglucinol staining of root cross-sections was used to verify the existence of an intact endodermis, suggesting that pharmaceuticals found in the leaf and seedpods of the plants were transported symplastically. PMID:20096438

  19. Understanding the Regulation of Cell Wall Composition in Alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L.) is the most important forage crop in the U.S. and has excellent potential to be a sustainable cellulosic feedstock for ethanol production. As the alfalfa stem matures, the xylem tissues become rich in cellulose, xylan, and lignin. The ideal alfalfa plant would have stems...

  20. Uptake of perfluorinated compounds by plants grown in nutrient solution.

    PubMed

    García-Valcárcel, A I; Molero, E; Escorial, M C; Chueca, M C; Tadeo, J L

    2014-02-15

    The uptake rates of three perfluorinated carboxylates and three perfluorinated sufonates by a grass (B diandrus) grown in nutrient solution at two different perfluorinated compounds (PFCs) concentrations were assessed. Grass can be ingested by grazing animals causing the PFCs to enter the food chain, which is a pathway of human exposure to these compounds. A rapid and miniaturized method was developed to determine PFCs in plants, based on a matrix solid-phase dispersion (MSPD) extraction procedure followed by quantitation by HPLC-MS/MS with an MQL in the range from 1 to 9 ng/g. An increase of PFCs levels in plant was observed along the exposure time. Differences in uptake for studied perfluorinated carboxylates were found, showing a decrease with carbon chain length (from 3027 to 1,167 ng/g at the end of assay), whereas no significant differences in absorption were obtained between perfluorinated sulfonates (about 1,700 ng/g). Initially, higher PFC transfer factors (ratio between concentration in plant and concentration in initial nutrient solution) were obtained for plants growing in the nutrient solution at the highest PFC concentration, but these factors became similar with time to plants exposed to the lowest concentration. PMID:24291554

  1. Some karyological observations on plants grown in space

    NASA Technical Reports Server (NTRS)

    Krikorian, A. D.; Oconnor, S. A.

    1982-01-01

    Experiments were conducted to assess whether cell division in a plant root would be affected by prolonged exposure to microgravity. Root materials from sunflower, oat, and mung bean plants grown on STS-2 and STS-3 were utilized for the experiments. It is found that all oat, sunflower, and mung seedlings showed a reduced number of cells in division as they went through their first cell division cycle on earth when compared to their ground controls. A significant number of oat, mung, and sunflower plantlets exhibited random root orientation and the lack of strictly orthotropic growth of their shoot systems in the flight samples. In addition, it is found that the mung roots were apparently least affected in terms of their cytology despite the fact that their roots were often randomly oriented.

  2. Automorphogenesis and gravitropism of plant seedlings grown under microgravity conditions

    NASA Astrophysics Data System (ADS)

    Hoson, T.; Saiki, M.; Kamisaka, S.; Yamashita, M.

    Plant seedlings exhibit automorphogenesis on clinostats. The occurrence of automorphogenesis was confirmed under microgravity in Space Shuttle STS-95 flight. Rice coleoptiles showed an inclination toward the caryopsis in the basal region and a spontaneous curvature in the same adaxial direction in the elongating region both on a three-dimensional (3-D) clinostat and in space. Both rice roots and Arabidopsis hypocotyls also showed a similar morphology in space and on the 3-D clinostat. In rice coleoptiles, the mechanisms inducing such an automorphic curvature were studied. The faster-expanding convex side of rice coleoptiles showed a higher extensibility of the cell wall than the opposite side. Also, in the convex side, the cell wall thickness was smaller, the turnover of the matrix polysaccharides was more active, and the microtubules oriented more transversely than the concave side, and these differences appear to be causes of the curvature. When rice coleoptiles grown on the 3-D clinostat were placed horizontally, the gravitropic curvature was delayed as compared with control coleoptiles. In clinostatted coleoptiles, the corresponding suppression of the amyloplast development was also observed. Similar results were obtained in Arabidopsis hypocotyls. Thus, the induction of automorphogenesis and a concomitant decrease in graviresponsiveness occurred in plant shoots grown under microgravity conditions.

  3. Deep-sequencing transcriptome analysis of field-grown Medicago sativa L. crown buds acclimated to freezing stress.

    PubMed

    Song, Lili; Jiang, Lin; Chen, Yue; Shu, Yongjun; Bai, Yan; Guo, Changhong

    2016-09-01

    Medicago sativa L. (alfalfa) 'Zhaodong' is an important forage legume that can safely survive in northern China where winter temperatures reach as low as -30 °C. Survival of alfalfa following freezing stress depends on the amount and revival ability of crown buds. In order to investigate the molecular mechanisms of frost tolerance in alfalfa, we used transcriptome sequencing technology and bioinformatics strategies to analyze crown buds of field-grown alfalfa during winter. We statistically identified a total of 5605 differentially expressed genes (DEGs) involved in freezing stress including 1900 upregulated and 3705 downregulated DEGs. We validated 36 candidate DEGs using qPCR to confirm the accuracy of the RNA-seq data. Unlike other recent studies, this study employed alfalfa plants grown in the natural environment. Our results indicate that not only the CBF orthologs but also membrane proteins, hormone signal transduction pathways, and ubiquitin-mediated proteolysis pathways indicate the presence of a special freezing adaptation mechanism in alfalfa. The antioxidant defense system may rapidly confer freezing tolerance to alfalfa. Importantly, biosynthesis of secondary metabolites and phenylalanine metabolism, which is of potential importance in coordinating freezing tolerance with growth and development, were downregulated in subzero temperatures. The adaptive mechanism for frost tolerance is a complex multigenic process that is not well understood. This systematic analysis provided an in-depth view of stress tolerance mechanisms in alfalfa. PMID:27272950

  4. The Role of Proanthocyanidins Complex in Structure and Nutrition Interaction in Alfalfa Forage.

    PubMed

    Jonker, Arjan; Yu, Peiqiang

    2016-01-01

    Alfalfa (Medicago sativa L.) is one of the main forages grown in the world. Alfalfa is a winter hardy, drought tolerant, N-fixing legume with a good longevity, high yield, high nutrient levels, high digestibility, unique structural to non-structural components ratio, high dry matter intake, and high animal productivity per hectare. However, its main limitation is its excessively rapid initial rate of protein degradation in the rumen, which results in pasture bloat and inefficient use of protein with consequent excessive excretions of nitrogen into the environment. Proanthocyanidins are secondary plant metabolites that can bind with protein and thereby reduce the rate and extent of ruminal protein degradation. However, these secondary metabolites do not accumulate in alfalfa. This review aims to firstly describe the events involved in the rapid release of protein from alfalfa and its effect on ruminant nutrition, environmental pollution, and pasture bloat; secondly, to describe occurrence, structure, functions and benefits of moderate amounts of proanthocyanidin; and finally, to describe the development of alfalfa which accumulates moderate amounts of proanthocyanidins. The emphasis of this review focuses on the role of proanthocyanidins compounds in structure and nutrition interaction in ruminant livestock systems. PMID:27223279

  5. The Role of Proanthocyanidins Complex in Structure and Nutrition Interaction in Alfalfa Forage

    PubMed Central

    Jonker, Arjan; Yu, Peiqiang

    2016-01-01

    Alfalfa (Medicago sativa L.) is one of the main forages grown in the world. Alfalfa is a winter hardy, drought tolerant, N-fixing legume with a good longevity, high yield, high nutrient levels, high digestibility, unique structural to non-structural components ratio, high dry matter intake, and high animal productivity per hectare. However, its main limitation is its excessively rapid initial rate of protein degradation in the rumen, which results in pasture bloat and inefficient use of protein with consequent excessive excretions of nitrogen into the environment. Proanthocyanidins are secondary plant metabolites that can bind with protein and thereby reduce the rate and extent of ruminal protein degradation. However, these secondary metabolites do not accumulate in alfalfa. This review aims to firstly describe the events involved in the rapid release of protein from alfalfa and its effect on ruminant nutrition, environmental pollution, and pasture bloat; secondly, to describe occurrence, structure, functions and benefits of moderate amounts of proanthocyanidin; and finally, to describe the development of alfalfa which accumulates moderate amounts of proanthocyanidins. The emphasis of this review focuses on the role of proanthocyanidins compounds in structure and nutrition interaction in ruminant livestock systems. PMID:27223279

  6. Gene expression from plants grown on the International Space Station

    NASA Astrophysics Data System (ADS)

    Stimpson, Alexander; Pereira, Rhea; Kiss, John Z.; Correll, Melanie

    Three experiments were performed on the International Space Station (ISS) in 2006 as part of the TROPI experiments. These experiments were performed to study graviTROPIsm and photoTROPIsm responses of Arabidopsis in microgravity (µg). Seedlings were grown with a variety of light and gravitational treatments for approximately five days. The frozen samples were returned to Earth during three space shuttle missions in 2007 and stored at -80° C. Due to the limited amount of plant biomass returned, new protocols were developed to minimize the amount of material needed for RNA extraction as a preparation for microarray analysis. Using these new protocols, RNA was extracted from several sets of seedlings grown in red light followed by blue light with one sample from 1.0g treatment and the other at µg. Using a 2-fold change criterion, microarray (Affymetrix, GeneChip) results showed that 613 genes were upregulated in the µg sample while 757 genes were downregulated. Upregulated genes in response to µg included transcription factors from the WRKY (15 genes), MYB (3) and ZF (8) families as well as those that are involved in auxin responses (10). Downregulated genes also included transcription factors such as MYB (5) and Zinc finger (10) but interestingly only two WRKY family genes were down-regulated during the µg treatment. Studies are underway to compare these results with other samples to identify the genes involved in the gravity and light signal transduction pathways (this project is Supported By: NASA NCC2-1200).

  7. Biological Control of Damping-Off of Alfalfa Seedlings with Bacillus cereus UW85.

    PubMed

    Handelsman, J; Raffel, S; Mester, E H; Wunderlich, L; Grau, C R

    1990-03-01

    We explored the potential of biological control of alfalfa (Medicago sativa L.) seedling damping-off caused by Phytophthora megasperma f. sp. medicaginis by screening root-associated bacteria for disease suppression activity in a laboratory bioassay. A total of 700 bacterial strains were isolated from the roots of field-grown alfalfa plants by using Trypticase soy agar. A simple, rapid assay was developed to screen the bacteria for the ability to reduce the mortality of Iroquois alfalfa seedlings that were inoculated with P. megasperma f. sp. medicaginis zoospores. Two-day-old seedlings were planted in culture tubes containing moist vermiculite, and each tube was inoculated with a different bacterial culture. Sufficient P. megasperma f. sp. medicaginis zoospores were added to each tube to result in 100% mortality of control seedlings. Of the 700 bacterial isolates tested, only 1, which was identified as Bacillus cereus and designated UW85, reduced seedling mortality to 0% in the initial screen and in two secondary screens. Both fully sporulated cultures containing predominantly released spores and sterile filtrates of these cultures of UW85 were effective in protecting seedlings from damping-off; filtrates of cultures containing predominantly vegetative cells or endospores inside the parent cell had low biocontrol activity. Cultures grown in two semidefined media had significantly greater biocontrol activities than cultures grown in the complex tryptic soy medium. In a small-scale trial in a field infested with P. megasperma f. sp. medicaginis, coating seeds with UW85 significantly increased the emergence of alfalfa. The results suggest that UW85 may have potential as a biocontrol agent for alfalfa damping-off, thus providing an alternative to current disease control strategies. PMID:16348145

  8. Herbivore responses to plants grown in enriched carbon dioxide atmospheres

    SciTech Connect

    Lincoln, D.E.

    1990-05-01

    Our initial study of sagebrush and grasshopper responses to elevated and historical carbon dioxide atmospheres is complete and has been accepted for publication. The study on Biomass Allocation Patterns of Defoliated Sagebrush Grown Under Two Levels of Carbon Dioxide has completed and the manuscript has been submitted for publication. We have completed the study of plant growth under two nutrient and carbon dioxide regimes and grasshopper feeding responses. The study of a specialist feeding caterpillar, the cabbage butterfly, and a mustard hostplant has recently been completed. We were able to identify the principal allelochemicals of the mustard plants, butenyl and pentenyl isothiocyanates, by combined gas chromatography and mass spectrometry. Measurement of these chemicals has been a critical component of this study since these compounds contain nitrogen and sulphur and act as a feeding stimulant to the caterpillar. This insect responds to elevated carbon dioxide by consuming more leaves and we can now say that this is not due to a change in the feeding stimulants. Reduced leaf protein content is a critical factor for even specialist feeding insect herbivores under elevated carbon dioxide conditions. The study on Grasshopper Population Responses to Enriched Carbon Dioxide Concentration is currently in progress at the Duke University Phytotron. We have changed hostplant species in order to complement the investigations of carbon dioxide effects on tallgrass prairie. Specifically, we are using big bluestem, Andropogon geradii, as the host plant to feed to the grasshoppers. This experiment will be completed in July 1990.

  9. The preferential binding of a sensory organ specific odorant binding protein of the alfalfa plant bug Adelphocoris lineolatus AlinOBP10 to biologically active host plant volatiles.

    PubMed

    Sun, Liang; Gu, Shao-Hua; Xiao, Hai-Jun; Zhou, Jing-Jiang; Guo, Yu-Yuan; Liu, Ze-Wen; Zhang, Yong-Jun

    2013-09-01

    Semiochemicals such as sex pheromones and plant volatiles are crucial components of insect mating systems and host plant localization. In the olfactory signal transduction pathway, odorant-binding proteins (OBPs) are important elements that function in the first step of the pathway by carrying hydrophobic semiochemicals across the sensillum lymph to the olfactory receptors (ORs). In this study, we examined the binding affinities of semiochemicals to AlinOBP10, a putative OBP from the alfalfa plant bug, Adelphocoris lineolatus, that we demonstrate is expressed mainly in sensory organs. We then characterized the biological activities of the high affinity semiochemicals by measuring their electrophysiological activities in antennae and behavioral responses in the plant bug. AlinOBP10 displayed weak binding affinities to two major putative pheromone components, hexyl butyrate and (E)-2-hexenyl butyrate. In contrast, AlinOBP10 exhibited higher binding affinities to six host plant volatiles, namely myrcene, β-pinene, β-ionone, 3-hexanone, (E)-2-hexenal, and 1-hexanol. The biological activities of these six putative ligands were further studied in electroantennogram recordings and Y-tube olfactometer trials. The three compounds, (E)-2-hexenal, 1-hexanol, and 3-hexanone elicited strong electrophysiological responses, but elicited distinct behaviors. While 3-hexanone was attractive to female adults, (E)-2-hexenal and 1-hexanol were significant repellents. Although a weak electrophysiological response was elicited with β-pinene, it was a strong repellent. These results demonstrate that AlinOBP10 can interact with attractants, as well as repellents, with some specificity toward plant volatiles over sex pheromones. PMID:23955060

  10. Alfalfa production with subsurface drip irrigation in the Central Great Plains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigated alfalfa production is gaining interest because of the growing number of dairies in the semi-arid U.S. Central Great Plains and its longstanding superior profitability compared to other alternative crops grown in the region. Irrigation requirements for alfalfa are great because of alfalfa's...

  11. Physical analysis of COMT and CCOMT downregulated alfalfa stems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Caffeic Acid 3-O-Methyltransferase (COMT) and Caffeoyl CoA 3-O-Methyltransferase (CCOMT) downregulated alfalfas (Medicago sativa L.) have been created. This study examined stem characteristics of these lignin downregulated alfalfas grown in three environments. Twenty COMT and twenty CCOMT downregu...

  12. New strategies for managing leaf diseases of alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaf diseases are a serious problem for alfalfa management in all areas where alfalfa is grown. Defoliation from leaf diseases has been measured from 3-71% depending on time of year, environmental conditions, age of the stand, and location. In addition to yield loss, foliar diseases can reduce forag...

  13. Effect of glyphosate on foliar diseases in Roundup Ready alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foliar diseases are a serious problem for alfalfa management in all areas where alfalfa is grown. Defoliation due to foliar diseases varies from 3-71% depending on time of year, environmental conditions, and locale. Fungicide treatments are cost-effective in only some years and locations. Recently, ...

  14. Effect of Mulch Surface Color on Root-knot of Tomato Grown in Simulated Planting Beds.

    PubMed

    Fortnum, B A; Kasperbauer, M J; Decoteau, D R

    2000-03-01

    The effect of different-colored polyethylene mulches on quantity and spectra of reflected light, plant morphology, and root-knot disease was studied in tomato (Lycopersicon esculentum) grown in simulated planting beds. Tomato plants were inoculated with Meloidogyne incognita at initial populations (Pi) of 0, 1,000, 10,000, or 50,000 eggs/plant, and grown in a greenhouse for 50 days over white, red, or black mulch. Soil temperature was kept constant among the mulch treatments by placing an insulation barrier between the colored mulch and the soil surface. Soil temperature varied less than 0.5 degrees C between soil chambers at solar noon. Tomatoes grown over white mulch received more reflected photosynthetic light and had greater shoot weights (27%), root weights (32%), and leaf area (20%) than plants grown over black mulch. Plants grown over red mulch received a higher far-red-to-red ratio in the reflected light. Mulch color altered the plant's response to root-knot nematode infection by changing the distribution of mass in axillary shoots. At high Pi, axillary leaf area and leaf weight were greater in tomato grown over white mulch than when grown over red mulch. The root-gall index was lower for plants grown over white mulch than similar plants grown over red mulch. PMID:19270954

  15. Lignin Modification Leads to Increased Nodule Numbers in Alfalfa1[C][W][OPEN

    PubMed Central

    Gallego-Giraldo, Lina; Bhattarai, Kishor; Pislariu, Catalina I.; Nakashima, Jin; Jikumaru, Yusuke; Kamiya, Yuji; Udvardi, Michael K.; Monteros, Maria J.; Dixon, Richard A.

    2014-01-01

    Reduction of lignin levels in the forage legume alfalfa (Medicago sativa) by down-regulation of the monolignol biosynthetic enzyme hydroxycinnamoyl coenzyme A:shikimate hydroxycinnamoyl transferase (HCT) results in strongly increased digestibility and processing ability of lignocellulose. However, these modifications are often also associated with dwarfing and other changes in plant growth. Given the importance of nitrogen fixation for legume growth, we evaluated the impact of constitutively targeted lignin modification on the belowground organs (roots and nodules) of alfalfa plants. HCT down-regulated alfalfa plants exhibit a striking reduction in root growth accompanied by an unexpected increase in nodule numbers when grown in the greenhouse or in the field. This phenotype is associated with increased levels of gibberellins and certain flavonoid compounds in roots. Although HCT down-regulation reduced biomass yields in both the greenhouse and field experiments, the impact on the allocation of nitrogen to shoots or roots was minimal. It is unlikely, therefore, that the altered growth phenotype of reduced-lignin alfalfa is a direct result of changes in nodulation or nitrogen fixation efficiency. Furthermore, HCT down-regulation has no measurable effect on carbon allocation to roots in either greenhouse or 3-year field trials. PMID:24406794

  16. Increased photosynthetic acclimation in alfalfa associated with arbuscular mycorrhizal fungi (AMF) and cultivated in greenhouse under elevated CO2.

    PubMed

    Goicoechea, Nieves; Baslam, Marouane; Erice, Gorka; Irigoyen, Juan José

    2014-11-15

    Medicago sativa L. (alfalfa) can exhibit photosynthetic down-regulation when grown in greenhouse conditions under elevated atmospheric CO2. This forage legume can establish a double symbiosis with nitrogen fixing bacteria and arbuscular mycorrhizal fungi (AMF), which may increase the carbon sink effect of roots. Our aim was to assess whether the association of alfalfa with AMF can avoid, diminish or delay the photosynthetic acclimation observed in previous studies performed with nodulated plants. The results, however, showed that mycorrhizal (M) alfalfa at the end of their vegetative period had lower carbon (C) discrimination than non-mycorrhizal (NM) controls, indicating photosynthetic acclimation under ECO2 in plants associated with AMF. Decreased C discrimination was due to the acclimation of conductance, since the amount of Rubisco and the expression of genes codifying both large and small subunits of Rubisco were similar or slightly higher in M than in NM plants. Moreover, M alfalfa accumulated a greater amount of soluble sugars in leaves than NM plants, thus favoring a down-regulation effect on photosynthetic rates. The enhanced contents of sugars in leaves coincided with a reduced percentage of arbuscules in roots, suggesting decreased sink of carbohydrates from shoots to roots in M plants. The shorter life cycle of alfalfa associated with AMF in comparison with the NM controls may also be related to the accelerated photosynthetic acclimation in M plants. Further research is needed to clarify to what extent this behavior could be extrapolated to alfalfa cultivated in the field and subjected to periodic cutting of shoots under climatic change scenarios. PMID:25240322

  17. Chemosensillum immunolocalization and ligand specificity of chemosensory proteins in the alfalfa plant bug Adelphocoris lineolatus (Goeze)

    PubMed Central

    Sun, Liang; Zhou, Jing-Jiang; Gu, Shao-Hua; Xiao, Hai-Jun; Guo, Yu-Yuan; Liu, Ze-Wen; Zhang, Yong-Jun

    2015-01-01

    Insect chemosensory proteins (CSPs) are a family of small soluble proteins. To date, their physiological functions in insect olfaction remain largely controversial in comparison to odorant binding proteins (OBPs). In present study, we reported the antenna specific expression of three CSPs (AlinCSP4-6) from Adelphocoris lineolatus, their distinct chemosensillum distribution as well as ligand binding capability thus providing the evidence for the possible roles that they could play in semiochemical detection of the plant bug A. lineolatus. The results of qRT-PCR and western blot assay clearly showed that all of these three CSPs are highly expressed in the adult antennae, the olfactory organ of insects. Further cellular investigation of their immunolocalization revealed their dynamic protein expression profiles among different types of antennal sensilla. In a fluorescence competitive binding assay, the selective ligand binding was observed for AlinCSP4-6. In ad`dition, a cooperative interaction was observed between two co-expressed CSPs resulting in an increase of the binding affinities by a mixture of AlinCSP5 and AlinCSP6 to terpenoids which do not bind to individual CSPs. These findings in combination with our previous data for AlinCSP1-3 indicate a possible functional differentiation of CSPs in the A. lineolatus olfactory system. PMID:25627422

  18. Alfalfa: bioenergy and more

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa) has the potential to be a significant contributor to America's renewable energy future. In an alfalfa biomass energy production system, alfalfa forage would be separated into stem and leave fractions. The stems would be processed to produce energy, and the leaves would be s...

  19. Alfalfa stem feedstock for IGCC power system fuel

    SciTech Connect

    DeLong, M.M.; Onischak, M.; Schmid, M.R.

    1995-12-31

    A feasibility study has been completed for an integrated gasification combined cycle power generation (IGCC) system that involves a set of inter-related processes between the alfalfa separation plant and the power plant. The alfalfa fractionation process reduces the stem size, improves the bulk density for feeding and provides a uniform moisture feed. Alfalfa stem material was evaluated as a fuel for the system. The leaf meal, animal feed co-product is separated from the alfalfa plant. The pressurized gasification process is the RENUGAS{trademark} system licensed to Tampella Power Corporation. The adaptation of the process to alfalfa stems results in low-Btu fuel gas suitable for combustion turbines. The gasification process is expected to obtain very high carbon conversion, overcome ash agglomeration, control volatile alkali species, and remove particulate matter with a hot gas filter system. The collected ash residues are expected to be returned to the land that grew the alfalfa.

  20. Antibacterial and antitumour activities of some plants grown in Turkey

    PubMed Central

    Usta, Canan; Yildirim, Arzu Birinci; Turker, Arzu Ucar

    2014-01-01

    Screening of antibacterial and antitumour activities of 33 different extracts prepared with three types of solvents (water, ethanol and methanol) was conducted. The extracts were obtained from 11 different plant species grown in Turkey: Eryngium campestre L., Alchemilla mollis (Buser) Rothm., Dorycnium pentaphyllum Scop., Coronilla varia L., Onobrychis oxyodonta Boiss., Fritillaria pontica Wahlenb., Asarum europaeum L., Rhinanthus angustifolius C. C. Gmelin, Doronicum orientale Hoffm., Campanula glomerata L. and Campanula olympica Boiss. Antibacterial activity against six bacteria was evaluated: Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Streptococcus pyogenes, Staphylococcus aureus and Staphylococcus epidermidis by using disc diffusion and well diffusion methods. S. aureus and S. epidermidis were most sensitive to the methanolic extract from A. europaeum. S. pyogenes was vulnerable to all used extracts of D. orientale. In addition, ethanolic or methanolic extracts of E. campestre, A. mollis, D. pentaphyllum, C. varia, R. angustifolius, C. glomerata and C. olympica displayed strong antibacterial activity against at least one of the tested gram-negative bacteria. The methanolic extract from R. angustifolius showed a broad-spectrum activity against both gram-positive and gram-negative bacteria. Antitumour activity was evaluated with Agrobacterium-tumefaciens-induced potato disc tumour assay. Best antitumour activity was obtained with the aqueous extract from A. europaeum and methanolic extract from E. campestre (100% and 86% tumour inhibition, respectively). PMID:26740759

  1. Broadening the U.S. alfalfa germplasm base

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over 4000 alfalfa (Medicago sativa L.) plant introductions (PIs) exist in the USDA-ARS National Plant Germplasm System (NPGS). NAAIC has discussed/proposed pre-breeding efforts to utilize this germplasm for creating pre-commercial alfalfa germplasm. Funding constraints have been one impediment to th...

  2. Assessment of Genetic Diversity Among Nondormant and Semi-Dormant Alfalfa Populations using Sequence Related Amplified Polymorphisms (SRAPs)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synthetic alfalfa populations consist of genetically heterogeneous plants, which has contributed to difficulties in applying molecular markers for examining genetic relationships among alfalfa cultivars. Molecular marker techniques combined with bulked plant DNA analyses provide perhaps the best com...

  3. Pathogenesis of Alfalfa mosaic virus in Soybean (Glycine max) and Expression of Chimeric Rabies Peptide in Virus-Infected Soybean Plants.

    PubMed

    Fleysh, N; Deka, D; Drath, M; Koprowski, H; Yusibov, V

    2001-10-01

    ABSTRACT Infection of soybean (Glycine max) plants inoculated with particles of Alfalfa mosaic virus (AlMV) isolate 425 at 12 days after germination was monitored throughout the life cycle of the plant (vegetative growth, flowering, seed formation, and seed maturation) by western blot analysis of tissue samples. At 8 to 10 days after inoculation, the upper uninoculated leaves showed symptoms of virus infection and accumulation of viral coat protein (CP). Virus CP was detectable in leaves, stem, roots, seedpods, and seed coat up to 45 days postinoculation (dpi), but only in the seedpod and seed coat at 65 dpi. No virus accumulation was detected in embryos and cotyledons at any time during infection, and no seed transmission of virus was observed. Soybean plants inoculated with recombinant AlMV passaged from upper uninoculated leaves of infected plants showed accumulation of full-length chimeric AlMV CP containing rabies antigen in systemically infected leaves and seed coat. These results suggest the potential usefulness of plants and plant viruses as vehicles for producing proteins of biomedical importance in a safe and inexpensive manner. Moreover, even the soybean seed coat, treated as waste tissue during conventional processing for oil and other products, may be utilized for the expression of value-added proteins. PMID:18944120

  4. Planting date effects on the nutritive value of fall-grown oat cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fall-grown oat (Avena sativa L.) shows potential to fill an important niche as emergency fall forage throughout central Wisconsin. Our objectives were to assess the effects of planting date on the nutritive value of fall-grown oat from four cultivars exhibiting diverse maturation characteristics. Du...

  5. T-DNA and opine synthetic loci in tumors incited by Agrobacterium tumefaciens A281 on soybean and alfalfa plants.

    PubMed Central

    Hood, E E; Chilton, W S; Chilton, M D; Fraley, R T

    1986-01-01

    We report here the molecular characterization of transferred DNA (T-DNA) in leguminous tumors incited by Agrobacterium tumefaciens A281 harboring the tumor-inducing plasmid pTiBo542. The T-DNA is composed of two regions named TL (left portion)-DNA and TR (right portion)-DNA, in accordance with the nomenclature for the octopine strains. TL-DNA is defined by several internal HindIII restriction fragments totaling 10.8 kilobase pairs (kbp) in uncloned soybean and alfalfa tumors. Alfalfa tumor DNA may contain one more HindIII fragment at the left end of TL-DNA than does soybean tumor DNA. TR-DNA has a 5.8-kbp BamHI-EcoRI internal fragment. All borders other than the left border of TL-DNA appear to be the same within the detection limits of Southern blot hybridization experiments. The two T-DNA regions are separated by 16 to 19 kbp of DNA not stably maintained in tumors. The distance from the left border of TL-DNA to the right border of TR-DNA is approximately 40 kbp. Loci for the mannityl opines are situated in TR-DNA, based on genetic and biochemical criteria. Images PMID:3023301

  6. T-DNA and opine synthetic loci in tumors incited by Agrobacterium tumefaciens A281 on soybean and alfalfa plants.

    PubMed

    Hood, E E; Chilton, W S; Chilton, M D; Fraley, R T

    1986-12-01

    We report here the molecular characterization of transferred DNA (T-DNA) in leguminous tumors incited by Agrobacterium tumefaciens A281 harboring the tumor-inducing plasmid pTiBo542. The T-DNA is composed of two regions named TL (left portion)-DNA and TR (right portion)-DNA, in accordance with the nomenclature for the octopine strains. TL-DNA is defined by several internal HindIII restriction fragments totaling 10.8 kilobase pairs (kbp) in uncloned soybean and alfalfa tumors. Alfalfa tumor DNA may contain one more HindIII fragment at the left end of TL-DNA than does soybean tumor DNA. TR-DNA has a 5.8-kbp BamHI-EcoRI internal fragment. All borders other than the left border of TL-DNA appear to be the same within the detection limits of Southern blot hybridization experiments. The two T-DNA regions are separated by 16 to 19 kbp of DNA not stably maintained in tumors. The distance from the left border of TL-DNA to the right border of TR-DNA is approximately 40 kbp. Loci for the mannityl opines are situated in TR-DNA, based on genetic and biochemical criteria. PMID:3023301

  7. Characterizing pathways of invasive plant spread to Alaska: I. propagules from container-grown ornamentals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To determine the size and nature of container-grown plant soil as a pathway for introduction of exotic plant species to Alaska, soil from ornamentals was obtained from vendors and was incubated in the greenhouse. Fifty four plant species were identified growing in containers or germinating from the ...

  8. Effect of Plant Spacing on Microclimate and Rhizoctonia Web Blight Development in Container Grown Azalea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rhizoctonia web blight is a reoccurring problem in compact varieties of container-grown azalea (Rhododendron sp.) in the Gulf Coast States. During the summers of 2002 and 2003, disease severity was measured weekly in the inoculated center plant of plots consisting of 49 ‘Gumpo’ azalea plants. Plant ...

  9. Evidence of association of salmonellae with tomato plants grown hydroponically in inoculated nutrient solution.

    PubMed

    Guo, Xuan; van Iersel, Marc W; Chen, Jinru; Brackett, Robert E; Beuchat, Larry R

    2002-07-01

    The possibility of uptake of salmonellae by roots of hydroponically grown tomato plants was investigated. Within 1 day of exposure of plant roots to Hoagland nutrient solution containing 4.46 to 4.65 log(10) CFU of salmonellae/ml, the sizes of the pathogen populations were 3.01 CFU/g of hypocotyls and cotyledons and 3.40 log(10) CFU/g of stems for plants with intact root systems (control) and 2.55 log(10) CFU/g of hypocotyls and cotyledons for plants from which portions of the roots had been removed. A population of > or =3.38 log(10) CFU/g of hypocotyls-cotyledons, stems, and leaves of plants grown for 9 days was detected regardless of the root condition. Additional studies need to be done to unequivocally demonstrate that salmonellae can exist as endophytes in tomato plants grown under conditions that simulate commonly used agronomic practices. PMID:12089054

  10. Effects of ozone and Fusarium root and crown rot on the growth and decline of Alfalfa, Medicago sativa L

    SciTech Connect

    Cooley, D.R.

    1986-01-01

    Research examined the reaction of several major alfalfa cultivars to ozone fumigations in chambers using ozone concentrations simulating ambient levels observed in Massachusetts. These cultivars were all shown to be susceptible in varying degrees to such ozone stress. Further experiments showed that ozone at these concentrations not only reduced growth, but also altered photoassimilate partitioning. Greatest weight reductions occurred in roots, followed by leaves, and then stems. Ozone-stressed plants produced fewer leaves which weighed less per unit area than control leaves. Classic and functional growth analyses were used to examine such parameters as net assimilation rate and relative growth rate. Ozone-stressed plants fixed dry matter less efficiently than control plants, in terms of both leaf area and existing dry matter. In a final study, alfalfa was grown in the presence of isolates of pathogenic Fusarium, or to soil from a diseased alfalfa field, and concurrently fumigated with ozone. There was no significant interaction between pathogen and air pollutant, but each stress significantly reduced alfalfa growth independently.

  11. Yield performance of cowpea plant introductions grown in calcareous soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important legume crop used as a feed for livestock, as a green vegetable and for consumption of its dry beans which provide 22-25% protein. The crop is very sensitive to alkaline soil conditions. When grown at a soil pH of 7.5 or higher, co...

  12. Alfalfa nitrogen credit to first-year corn: potassium, regrowth, and tillage timing effects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Compared to corn (Zea mays L.) following corn, N guidelines for corn following alfalfa (Medicago sativa L.) in the U.S. Corn Belt suggest that N rates for first-year corn after alfalfa be reduced by about 168 kg N/ha when 43 to 53 alfalfa plants per square meter are present at termination; however, ...

  13. Soil N to corn after alfalfa through tillage and regrowth management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Planting corn after alfalfa can eliminate or greatly reduce the nitrogen (N) fertilizer requirement for first-year corn while increasing corn yield potential due to the rotation effect. Current University of Minnesota guidelines regarding alfalfa N credits to corn are based on alfalfa stand density ...

  14. Modeling feral alfalfa (Medicago sativa subsp. sativa L.) occurrence using topographical and environmental variables

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because alfalfa is a perennial species cross pollinated by bees and can establish along roadsides and ruderal areas, there is concern that feral plants can serve as reservoirs and conduits for transgenic genes. The objective of this study was to survey feral alfalfa in alfalfa seed production areas ...

  15. Corn response to nitrogen after alfalfa as affected by tillage and regrowth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current N guidelines for corn following alfalfa in Minnesota suggest that when compared to corn following corn, N rates for first-year corn after alfalfa can be reduced by 168 kg N/ha when greater than or equal to 43 alfalfa plants/square meter are present at termination. Two unanswered questions re...

  16. Opportunities exist to improve alfalfa and manure nitrogen crediting in corn following alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A survey was conducted in 2012 to evaluate the acceptance of fertilizer and manure N extension N rate guidelines for corn (Zea mays L.) grown as the first (AC) and second (ACC) crop following alfalfa (Medicago sativa L.) during 2009 to 2011 in Minnesota. There were 421 valid responses for AC and 273...

  17. Reduced Lignin Alfalfa - Update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    U.S. farmers harvested alfalfa (Medicago sativa) for hay or haylage from 24.5million acres in 2009. Midwestern states harvested 57 % of 2009 acreage for hay and haylage. However, acreage is stable to declining. Alfalfa provides an excellent source of fiber, protein, minerals and vitamins that partia...

  18. ALFALFA: BIOFUEL AND FEED

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa hay is a major crop that supports Idaho's dairy industry. Several cellulosic feedstocks will be needed to meet current ethanol production goals. Alfalfa has considerable potential as a feedstock for production of ethanol and other industrial materials because of its high biomasss production...

  19. Intended release and actual retention of alfalfa leafcutting bees (hymenoptera: megachilidae) for pollination in commercial alfalfa seed fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low, medium, and high stocking densities of Megachile rotundata, the alfalfa leafcutting bee, were released over four years in three research plots of Utah alfalfa planted at seed-production rates. A low number of bees (46-79% of released) survived the incubation and field emergence processes, and ...

  20. Root Zone Respiration on Hydroponically Grown Wheat Plant Systems

    NASA Technical Reports Server (NTRS)

    Soler-Crespo, R. A.; Monje, O. A.

    2010-01-01

    Root respiration is a biological phenomenon that controls plant growth and physiological development during a plant's lifespan. This process is dependent on the availability of oxygen in the system where the plant is located. In hydroponic systems, where plants are submerged in a solution containing vital nutrients but no type of soil, the availability of oxygen arises from the dissolved oxygen concentration in the solution. This oxygen concentration is dependent on the , gas-liquid interface formed on the upper surface of the liquid, as given by Henry's Law, depending on pressure and temperature conditions. Respiration rates of the plants rise as biomass and root zone increase with age. The respiration rate of Apogee wheat plants (Triticum aestivum) was measured as a function of light intensity (catalytic for photosynthesis) and CO2 concentration to determine their effect on respiration rates. To determine their effects on respiration rate and plant growth microbial communities were introduced into the system, by Innoculum. Surfactants were introduced, simulating gray-water usage in space, as another factor to determine their effect on chemical oxygen demand of microbials and on respiration rates of the plants. It is expected to see small effects from changes in CO2 concentration or light levels, and to see root respiration decrease in an exponential manner with plant age and microbial activity.

  1. Alfalfa non-feed uses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Non-feed uses for alfalfa such as biomass energy and phytoremediation could increase alfalfa acreage and improve farm profitability. The new bio-energy alfalfa and production system increased forage yield and ethanol production. New alfalfas with enhanced nitrogen cycling capacities would protect wa...

  2. Review of Roundup Ready Alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Roundup Ready (RR) alfalfa is the first forage species commercially released with a genetically modified trait. While not needed by all farmers who grow alfalfa, RR alfalfa may allow some farmers to more effectively establish alfalfa and control certain weed problems. Gene flow potential in alfalf...

  3. Control of Pratylenchus penetrans and Meloidogyne hapla and Yield Response of Alfalfa Due to Oxamyl Seed Treatments

    PubMed Central

    Townshend, J. L.; Chiba, M.

    1987-01-01

    Alfalfa (Medicago sativa L. cv. Saranac) seed were soaked for 20 minutes in water, acetone, or methanol containing 10 or 50 mg/ml of oxamyl (Vydate L) or coated with a 2% aqueous cellulose solution containing the same amounts of oxamyl. Seed were analyzed for oxamyl by HPLC immediately after treatment and after 9 and 26 months of storage. Oxamyl content of alfalfa seed did not decline after 26 months of storage. The effects of seed treatment on growth of alfalfa and nematode control were examined using soils infested with Pratylenchus penetrans and Meloidogyne hapla. Germination was not affected by any of the seed treatments. Twenty-one days after sowing, the total growth of alfalfa seedlings grown from seed treated with 50 mg/ml of oxamyl in P. penetrans-infested soils had increased by 62% over controls. Nodulation per pot increased by as much as 267%, and the densities of P. penetrans per gram of root were reduced by as much as 73% compared to control plants. In M. hapla-infested soils, increases in plant growth (32%) and nodulation (71%) also occurred with oxamyl-treated seeds. Root gall reduction (86%) was also substantial due to oxamyl seed treatment. PMID:19290170

  4. Experiments on plants grown in space. Status and prospects

    NASA Technical Reports Server (NTRS)

    Halstead, T. W.; Dutcher, F. R.

    1984-01-01

    Space flight provides a unique capability to gravitational research by providing an environment in which gravity can be manipulated below the Earth norm of 1 to a state comparable to weightlessness. Although space experiments with seeds and plants have been conducted for almost 25 years, we are only now entering an era that promises the capability of routinely conducting controlled plant experiments in space. Results from experiments with higher plants and seeds flown thus far in both manned and unmanned spacecraft from both the USA and USSR are briefly summarized. An overview of the current status of space biology experimentation as it relates to plants is presented and present and future opportunities to conduct plant experiments under space flight conditions are discussed.

  5. Ractopamine up take by alfalfa (Medicago sativa) and wheat (Triticum aestivum) from soil.

    PubMed

    Shelver, Weilin L; DeSutter, Thomas M

    2015-08-01

    Ractopamine is a beta adrenergic agonist used as a growth promoter in swine, cattle and turkeys. To test whether ractopamine has the potential to accumulate in plants grown in contaminated soil, a greenhouse study was conducted with alfalfa (Medicago sativa) and wheat (Triticum aestivum) grown in two soils having different concentrations of organic matter (1.3% and 2.1%), amended with 0, 0.5, and 10 μg/g of ractopamine. Plant growth ranged from 2.7 to 8.8 g dry weight (dw) for alfalfa, and 8.7 to 40 g dw for wheat and was generally greater in the higher organic matter content soil. The uptake of ractopamine in plant tissues ranged from non-detectable to 897 ng/g and was strongly dependent on soil ractopamine concentration across soil and plant tissue. When adjusted to the total fortified quantities, the amount of ractopamine taken up by the plant tissue was low, <0.01% for either soil. PMID:26257350

  6. Spectral quality affects disease development of three pathogens on hydroponically grown plants

    NASA Technical Reports Server (NTRS)

    Schuerger, A. C.; Brown, C. S.; Sager, J. C. (Principal Investigator)

    1997-01-01

    Plants were grown under light-emitting diode (LED) arrays with various spectra to determine the effects of light quality on the development of diseases caused by tomato mosaic virus (ToMV) on pepper (Capsicum annuum L.), powdery mildew [Sphaerotheca fuliginea (Schlectend:Fr.) Pollaci] on cucumber (Cucumis sativus L.), and bacterial wilt (Pseudomonas solanacearum Smith) on tomato (Lycopersicon esculentum Mill.). One LED (660) array supplied 99% red light at 660 nm (25 nm bandwidth at half-peak height) and 1% far-red light between 700 to 800 nm. A second LED (660/735) array supplied 83% red light at 660 nm and 17% far-red light at 735 nm (25 nm bandwidth at half-peak height). A third LED (660/BF) array supplied 98% red light at 660 nm, 1% blue light (BF) between 350 to 550 nm, and 1% far-red light between 700 to 800 nm. Control plants were grown under broad-spectrum metal halide (MH) lamps. Plants were grown at a mean photon flux (300 to 800 nm) of 330 micromoles m-2 s-1 under a 12-h day/night photoperiod. Spectral quality affected each pathosystem differently. In the ToMV/pepper pathosystem, disease symptoms developed slower and were less severe in plants grown under light sources that contained blue and UV-A wavelengths (MH and 660/BF treatments) compared to plants grown under light sources that lacked blue and UV-A wavelengths (660 and 660/735 LED arrays). In contrast, the number of colonies per leaf was highest and the mean colony diameters of S. fuliginea on cucumber plants were largest on leaves grown under the MH lamp (highest amount of blue and UV-A light) and least on leaves grown under the 660 LED array (no blue or UV-A light). The addition of far-red irradiation to the primary light source in the 660/735 LED array increased the colony counts per leaf in the S. fuliginea/cucumber pathosystem compared to the red-only (660) LED array. In the P. solanacearum/tomato pathosystem, disease symptoms were less severe in plants grown under the 660 LED array, but the

  7. Nutrient Considerations for Plants Grown Under Space Flight Conditions

    NASA Technical Reports Server (NTRS)

    Levine, Howard G.; Krikorian, Abraham D.

    2006-01-01

    We present here results on the analysis of 100 mL medium samples extracted from sterilized foam (Smithers-Oasis, Kent OH) used to support the growth of both dicotyledonous (Haplopappus gracilis, n=75) and monocotyledonous (Hemerocallis cv Autumn Blaze, n=25) aseptic plants in NASA's Plant Growth Unit (PGU) during the 5-day CHROMEX-01 Space Shuttle flight (March 1989, STS-29). At recovery, the medium remaining within each of the five floral foam blocks (for both the space flight and ground control experiments) was extracted under vacuum, filtered and subjected to elemental analyses. Concentration levels of some elements remained the same, while some decreased and others increased. A unique aspect of this experiment was that all plants were either aseptic tissue culture generated plantlets or sterile seedling clones, and the design of the PGU facilitated the maintenance of asepsis throughout the mission (confirmed by postflight microbial sampling). This permitted the elimination of microbial considerations in the interpretation of the data. The significance of these findings for growing plants in altered gravity environments are discussed.

  8. Metal uptake of tomato and alfalfa plants as affected by water source, salinity, and Cd and Zn levels under greenhouse conditions.

    PubMed

    Gharaibeh, Mamoun A; Marschner, Bernd; Heinze, Stefanie

    2015-12-01

    Irrigation with wastewater is a promising option to improve crop yields and to reduce pressure on freshwater sources. However, heavy metal concentrations in wastewater may cause health concerns. A greenhouse pot experiment was conducted in order to determine cadmium (Cd) and zinc (Zn) concentrations in sandy soil and plant tissues of tomato (Lycopersicon esculentum L.) and alfalfa (Medicago sativa L.). A 2 × 2 × 4 × 2 factorial treatment arrangement was utilized. Two water sources, fresh (FW) or treated wastewater (TWW), at two salinity levels (1 and 3 dS m(-1)) containing different levels of Cd and Zn were used. Samples were collected after a 90-day growth period. It was observed that the growth of both plants was depressed at the highest metal level (L3). Metal accumulation in plant parts increased with the increase of metal concentration and salinity in irrigation water. At low salinity, water source was the main factor which controlled metal accumulation, whereas, at high salinity, chloride appeared to be the principal factor controlling metal uptake regardless of water source. Metal translocation from roots to shoots increased in TWW-irrigated plants, even in the controls. Tomatoes accumulated Cd up to and above critical levels safe for human consumption, even though Cd concentration in irrigation water did not exceed the current recommended values. Therefore, food production in sandy soils may well pose a health hazard when irrigated with TWW containing heavy metals. Complexation with dissolved organic compounds (DOC) in TWW may be to be the principal factor responsible for increased metal uptake and transfer at low salinity, thereby increasing the risk of heavy metal contamination of food and forage crops. PMID:26206131

  9. Aspartate Aminotransferase in Alfalfa Root Nodules 1

    PubMed Central

    Farnham, Mark W.; Griffith, Stephen M.; Miller, Susan S.; Vance, Carroll P.

    1990-01-01

    Aspartate aminotransferase (AAT) plays an important role in nitrogen metabolism in all plants and is particularly important in the assimilation of fixed N derived from the legume-Rhizoblum symbiosis. Two isozymes of AAT (AAT-1 and AAT-2) occur in alfalfa (Medicago sativa L.). Antibodies against alfalfa nodule AAT-2 do not recognize AAT-1, and these antibodies were used to study AAT-2 expression in different tissues and genotypes of alfalfa and also in other legume and nonlegume species. Rocket immunoelectrophoresis indicated that nodules of 38-day-old alfalfa plants contained about eight times more AAT-2 than did nodules of 7-day-old plants, confirming the nodule-enhanced nature of this isozyme. AAT-2 was estimated to make up 16, 15, 5, and 8 milligrams per gram of total soluble protein in mature nodules, roots, stems, and leaves, respectively, of effective N2-fixing alfalfa. The concentration of AAT-2 in nodules of ineffective non-N2-fixing alafalfa genotypes was about 70% less than that of effective nodules. Western blots of soluble protein from nodules of nine legume species indicated that a 40-kilodalton polypeptide that reacts strongly with AAT-2 antibodies is conserved in legumes. Nodule AAT-2 immunoprecipitation data suggested that amide- and ureide-type legumes may differ in expression and regulation of the enzyme. In addition, Western blotting and immunoprecipitations of AAT activity demonstrated that antibodies against alfalfa AAT-2 are highly cross-reactive with AAT enzyme protein in leaves of soybean (Glycine max L.), wheat (Triticum aestivum L.), and maize (Zea mays L.) and in roots of maize, but not with AAT in soybean and wheat roots. Results from this study indicate that AAT-2 is structurally conserved and localized in similar tissues among diverse species. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:16667896

  10. Synthetic mimicking of plant oils and comparison with naturally grown products in polyurethane synthesis.

    PubMed

    Coles, Stuart R; Barker, Guy; Clark, Andrew J; Kirwan, Kerry; Jacobs, Daniel; Makenji, Kylash; Pink, David

    2008-06-11

    The use of plant oils as industrial feedstocks can often be hampered by their lack of optimization towards a particular process, as well as their development being risky; growing suitable volumes of crops to test can take up to five years. To circumvent this, we aimed to discover a method that would mimic plant oil profiles in the laboratory, and show that they exhibited similar properties to the naturally grown plant oils in a given process. Using the synthesis of polyurethanes as an example, we have synthesized six different polymers and demonstrated that plant oils will produce polymers with similar physical properties to those oils mimicked in the laboratory. The use of this mimicking process can be extended to other types of polymers to obtain a method for predicting the properties of a given material based on the plant oil composition of a crop before it is grown in bulk. PMID:18322912

  11. Toxic Effects of Copper-based Nanoparticles or Compounds to Lettuce (Lactuca sativa) and Alfalfa (Medicago sativa)

    PubMed Central

    Hong, Jie; Rico, Cyren; Zhao, Lijuan; Adeleye, Adeyemi S.; Keller, Arturo A.; Peralta-Videa, Jose R.; Gardea-Torresdey, Jorge L.

    2014-01-01

    The increased production and use of nanoparticles (NPs) has generated concerns about their impact on living organisms. In this study, nCu, bulk Cu, nCuO, bulk CuO, Cu(OH)2 (CuPRO 2005, Kocide 3000), and CuCl2 were exposed for 15 days to 10 day-old hydroponically grown lettuce (Lactuca sativa) and alfalfa (Medicago sativa). Each compound was applied at 0, 5, 10, and 20 mg/L. At harvest, we measured the size of the plants and determined the concentration of Cu, macro and microelements by using ICP-OES. Catalase and ascorbate peroxidase activity was also determined. Results showed that all Cu NPs/compounds reduced the root length by 49% in both plant species. All Cu NPs/compounds increased Cu, P, and S (>100%, >50%, and >20%, respectively) in alfalfa shoots and decreased P and Fe in lettuce shoot (>50% and >50%, respectively, excluding Fe in CuCl2 treatment). Biochemical assays showed reduced catalase activity in alfalfa (root and shoot) and increased ascorbate peroxidase activity in roots of both plant species. Results suggest that Cu NPs/compounds not only reduced the size of the plants but altered nutrient content and enzyme activity in both plant species. PMID:25474419

  12. Physiological Response of Plants Grown on Porous Ceramic Tubes

    NASA Technical Reports Server (NTRS)

    Tsao, David; Okos, Martin

    1997-01-01

    This research involves the manipulation of the root-zone water potential for the purposes of discriminating the rate limiting step in the inorganic nutrient uptake mechanism utilized by higher plants. This reaction sequence includes the pathways controlled by the root-zone conditions such as water tension and gradient concentrations. Furthermore, plant based control mechanisms dictated by various protein productions are differentiated as well. For the nutrients limited by the environmental availability, the kinetics were modeled using convection and diffusion equations. Alternatively, for the nutrients dependent upon enzyme manipulations, the uptakes are modeled using Michaelis-Menten kinetics. In order to differentiate between these various mechanistic steps, an experimental apparatus known as the Porous Ceramic Tube - Nutrient Delivery System (PCT-NDS) was used. Manipulation of the applied suction pressure circulating a nutrient solution through this system imposes a change in the matric component of the water potential. This compensates for the different osmotic components of water potential dictated by nutrient concentration. By maintaining this control over the root-zone conditions, the rate limiting steps in the uptake of the essential nutrients into tomato plants (Lycopersicon esculentum cv. Cherry Elite) were differentiated. Results showed that the uptake of some nutrients were mass transfer limited while others were limited by the enzyme kinetics. Each of these were adequately modeled with calculations and discussions of the parameter estimations provided.

  13. Rapid phenotyping of alfalfa root system architecture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Root system architecture (RSA) influences the capacity of an alfalfa plant for symbiotic nitrogen fixation, nutrient uptake and water use efficiency, resistance to frost heaving, winterhardiness, and some pest and pathogen resistance. However, we currently lack a basic understanding of root system d...

  14. Yield and ion relations of alfalfa (Medicago sativa L.) in response to irrigation with saline waters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is a major forage crop utilized in arid and semi-arid regions under irrigation; these regions are commonly impacted by saline water and soils. Four commercial non-dormant, purported salt tolerant Alfalfa cultivars 'Salado', 'S&W8421s', 'S&W9720' and 'S&W9215' were grown in 24 outdoor sand ta...

  15. Differential effect of metals/metalloids on the growth and element uptake of mesquite plants obtained from plants grown at a copper mine tailing and commercial seeds.

    PubMed

    Haque, N; Peralta-Videa, J R; Duarte-Gardea, M; Gardea-Torresdey, J L

    2009-12-01

    The selection of appropriate seeds is essential for the success of phytoremediation/restoration projects. In this research, the growth and elements uptake by the offspring of mesquite plants (Prosopis sp.) grown in a copper mine tailing (site seeds, SS) and plants derived from vendor seeds (VS) was investigated. Plants were grown in a modified Hoagland solution containing a mixture of Cu, Mo, Zn, As(III) and Cr(VI) at 0, 1, 5 and 10 mg L(-1) each. After one week, plants were harvested and the concentration of elements was determined by using ICP-OES. At 1 mg L(-1), plants originated from SS grew faster and longer than control plants (0 mg L(-1)); whereas plants grown from VS had opposite response. At 5 mg L(-1), 50% of the plants grown from VS did not survive, while plants grown from SS had no toxicity effects on growth. Finally, plants grown from VS did not survive at 10 mg L(-1) treatment, whilst 50% of the plants grown from SS survived. The ICP-OES data demonstrated that at 1 mg L(-1) the concentration of all elements in SS plants was significantly higher compared to control plants and VS plants. While at 5 mg L(-1), the shoots of SS plants had significantly more Cu, Mo, As, and Cr. The results suggest that SS could be a better source of plants intended to be used for phytoremediation of soil impacted with Cu, Mo, Zn, As and Cr. PMID:19631524

  16. Enhanced tolerance and remediation to mixed contaminates of PCBs and 2,4-DCP by transgenic alfalfa plants expressing the 2,3-dihydroxybiphenyl-1,2-dioxygenase.

    PubMed

    Wang, Yan; Ren, Hejun; Pan, Hongyu; Liu, Jinliang; Zhang, Lanying

    2015-04-01

    Polychlorinated biphenyls (PCBs) and 2,4-dichlorophenol (2,4-DCP) generally led to mixed contamination of soils as a result of commercial and agricultural activities. Their accumulation in the environment poses great risks to human and animal health. Therefore, the effective strategies for disposal of these pollutants are urgently needed. In this study, genetic engineering to enhance PCBs/2,4-DCP phytoremediation is a focus. We cloned the 2,3-dihydroxybiphenyl-1,2-dioxygenase (BphC.B) from a soil metagenomic library, which is the key enzyme of aerobic catabolism of a variety of aromatic compounds, and then it was expressed in alfalfa driven by CaMV 35S promoter using Agrobacterium-mediated transformation. Transgenic line BB11 was selected out through PCR, Western blot analysis and enzyme activity assays. Its disposal and tolerance to both PCBs and 2,4-DCP were examined. The tolerance capability of transgenic line BB11 towards complex contaminants of PCBs/2,4-DCP significantly increased compared with non-transgenic plants. Strong dissipation of PCBs and high removal efficiency of 2,4-DCP were exhibited in a short time. It was confirmed expressing BphC.B would be a feasible strategy to help achieving phytoremediation in mixed contaminated soils with PCBs and 2,4-DCP. PMID:25590820

  17. Patellins 3 and 6, two members of the Plant Patellin family, interact with the movement protein of Alfalfa mosaic virus and interfere with viral movement.

    PubMed

    Peiro, Ana; Izquierdo-Garcia, Ana Cristina; Sanchez-Navarro, Jesus Angel; Pallas, Vicente; Mulet, Jose Miguel; Aparicio, Frederic

    2014-12-01

    Movement proteins (MPs) encoded by plant viruses interact with host proteins to facilitate or interfere with intra- and/or intercellular viral movement. Using yeast two-hybrid and bimolecular fluorescence complementation assays, we herein present in vivo evidence for the interaction between Alfalfa mosaic virus (AMV) MP and Arabidopsis Patellin 3 (atPATL3) and Patellin 6 (atPATL6), two proteins containing a Sec14 domain. Proteins with Sec14 domains are implicated in membrane trafficking, cytoskeleton dynamics, lipid metabolism and lipid-mediated regulatory functions. Interestingly, the overexpression of atPATL3 and/or atPATL6 interfered with the plasmodesmata targeting of AMV MP and correlated with reduced infection foci size. Consistently, the viral RNA levels increased in the single and double Arabidopsis knockout mutants for atPATL3 and atPATL6. Our results indicate that, in general, MP-PATL interactions interfere with the correct subcellular targeting of MP, thus rendering the intracellular transport of viral MP-containing complexes less efficient and diminishing cell-to-cell movement. PMID:24751128

  18. Characterization of culturable bacterial endophytes and their capacity to promote plant growth from plants grown using organic or conventional practices.

    PubMed

    Xia, Ye; DeBolt, Seth; Dreyer, Jamin; Scott, Delia; Williams, Mark A

    2015-01-01

    Plants have a diverse internal microbial biota that has been shown to have an important influence on a range of plant health attributes. Although these endophytes have been found to be widely occurring, few studies have correlated agricultural production practices with endophyte community structure and function. One agricultural system that focuses on preserving and enhancing soil microbial abundance and biodiversity is organic farming, and numerous studies have shown that organically managed system have increased microbial community characteristics. Herein, the diversity and specificity of culturable bacterial endophytes were evaluated in four vegetable crops: corn, tomato, melon, and pepper grown under organic or conventional practices. Endophytic bacteria were isolated from surface-sterilized shoot, root, and seed tissues and sequence identified. A total of 336 bacterial isolates were identified, and grouped into 32 species and five phyla. Among these, 239 isolates were from organically grown plants and 97 from those grown conventionally. Although a diverse range of bacteria were documented, 186 were from the Phylum Firmicutes, representing 55% of all isolates. Using the Shannon diversity index, we observed a gradation of diversity in tissues, with shoots and roots having a similar value, and seeds having the least diversity. Importantly, endophytic microbial species abundance and diversity was significantly higher in the organically grown plants compared to those grown using conventional practices, potentially indicating that organic management practices may increase endophyte presence and diversity. The impact that these endophytes could have on plant growth and yield was evaluated by reintroducing them into tomato plants in a greenhouse environment. Of the bacterial isolates tested, 61% were found to promote tomato plant growth and 50-64% were shown to enhance biomass accumulation, illustrating their potential agroecosystem application. PMID:26217348

  19. Characterization of culturable bacterial endophytes and their capacity to promote plant growth from plants grown using organic or conventional practices

    PubMed Central

    Xia, Ye; DeBolt, Seth; Dreyer, Jamin; Scott, Delia; Williams, Mark A.

    2015-01-01

    Plants have a diverse internal microbial biota that has been shown to have an important influence on a range of plant health attributes. Although these endophytes have been found to be widely occurring, few studies have correlated agricultural production practices with endophyte community structure and function. One agricultural system that focuses on preserving and enhancing soil microbial abundance and biodiversity is organic farming, and numerous studies have shown that organically managed system have increased microbial community characteristics. Herein, the diversity and specificity of culturable bacterial endophytes were evaluated in four vegetable crops: corn, tomato, melon, and pepper grown under organic or conventional practices. Endophytic bacteria were isolated from surface-sterilized shoot, root, and seed tissues and sequence identified. A total of 336 bacterial isolates were identified, and grouped into 32 species and five phyla. Among these, 239 isolates were from organically grown plants and 97 from those grown conventionally. Although a diverse range of bacteria were documented, 186 were from the Phylum Firmicutes, representing 55% of all isolates. Using the Shannon diversity index, we observed a gradation of diversity in tissues, with shoots and roots having a similar value, and seeds having the least diversity. Importantly, endophytic microbial species abundance and diversity was significantly higher in the organically grown plants compared to those grown using conventional practices, potentially indicating that organic management practices may increase endophyte presence and diversity. The impact that these endophytes could have on plant growth and yield was evaluated by reintroducing them into tomato plants in a greenhouse environment. Of the bacterial isolates tested, 61% were found to promote tomato plant growth and 50–64% were shown to enhance biomass accumulation, illustrating their potential agroecosystem application. PMID:26217348

  20. Impact of ozone on quantity and quality of greenhouse-grown potato plants

    SciTech Connect

    Pell, E.J.; Weissberger, W.C.; Speroni, J.J.

    1980-05-01

    The impact of ozone on quality and quantity of greenhouse-grown potatoes was considered. In two experiments conducted in 1977 and 1978, 'Norland' and 'Kennebec' potato plants were grown in a conventional greenhouse. Once every 2 weeks, 10 plants of each cultivar were exposed to 387 ..mu..g/m/sup 3/ (0.20 ppm) ozone for 3 h in a controlled environment chamber. At 120 and 140 days, for 'Norland' and 'Kennebec', respectively, vines were killed and tubers were harvested. The number and weight of tubers harvested from ozonized plants decreased significantly in both cultivars. Significant decreases in total solids and increases in reducing sugars of tubers from ozone-exposed plants were identified.

  1. Impact of ozone on quantity and quality of greenhouse-grown potato plants

    SciTech Connect

    Pell, E.J.; Weissberger, W.C.; Speroni, J.J.

    1980-05-01

    The impact of ozone on quality and quantity of greenhouse-grown potatoes was considered. In two experiments conducted in 1977 and 1978, Norland and Kennebec potato plants were grown in a conventional greenhouse. Once every 2 weeks, 10 plants of each cultivar were exposed to 387 ..mu..g/m/sup 3/ (0.20 ppm) ozone for 3 h in a controlled environment chamber. At 120 and 140 days, for Norland and Kennebec, respectively, vines were killed and tubers were harvested. The number and weight of tubers harvested from ozonized plants decreased significantly in both cultivars. Significant decreases in total solids and increases in reducing sugars of tubers from ozone-exposed plants were identified.

  2. Natural and introduced Fusarium verticillioides populations in ears of field-grown corn plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn may be colonized by the fungus, Fusarium verticillioides, resulting in both plant disease and mycotoxin contamination. The purpose of the current research was to compare frequencies of three F. verticillioides populations in kernels of corn grown under field conditions. The populations assess...

  3. Nutrient uptake and loss by container-grown deciduous and evergreen Rhododendron nursery plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of N fertilizer application on plant uptake and demand for other nutrients was evaluated from May 2005 to February 2006 in container-grown evergreen Rhododendron ‘P.J.M. Compact’ (PJM) and ‘English Roseum’ (ER) and deciduous Rhododendron ‘Gibraltar’ (AZ). Increased N-availability incre...

  4. Planting date effects on the yield and nutritive value of fall-grown oat cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For the dairy industry within the north-central U.S., options for producing emergency forage are limited when late-summer or fall inventories are inadequate, primarily because of the relatively short growing season. Fall-grown cereal crops can fill this niche, but knowing what to plant and when to p...

  5. Rhizoctonia Species Associated With Bark Media and Plant Strata of Container-Grown Azalea

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Symptoms of Rhizoctonia web blight, caused predominantly by binucleate Rhizoctonia (BNR) anastomosis group U, develops annually from late-June to mid-September on container-grown azaleas (Rhododendron spp.) in the southern United States. In 2005 and 2006, ‘Gumpo White’ azalea plants with a disease ...

  6. Feasibility study: Alfalfa leaf meal as a value-added crop and alfalfa stems as biomass fuel. Final report

    SciTech Connect

    Gray, A.; Kaan, D.

    1996-05-28

    The grantee recognizes the importance of alfalfa production to agricultural economics in the western United States. With this grant, it secured the assistance of experts at the University of Wyoming to explore alternative uses for and, thus, ways to add value to alfalfa. The study was prompted by periodic unstable demand and price fluctuations for hay. The agricultural infrastructure and expertise for producing alfalfa is well established in the Western U.S. Alfalfa is a well-adapted, environmentally friendly crop which avoids a large fertilizer subsidy by fixing atmospheric nitrogen into a form utilized for plant growth. Leaf-stem fractions were evaluated for forage quality, biofuel energy content, and co-product yield due to seperation procedure. The feasibility of conducting alfalfa leaf-stem separations in both stationary and mobile plants was considered on the basis of three factors: (1) price received for each fraction, (2) cost of the hay to be processed, and (3) cost of processing the hay. Both stationary and mobile separation plants showed positive net income potentials. Alfalfa stem pellets could be marked at appreciably lower cost than equivalent wood pellets for use in wood stoves. The report recommends that sufficient quantities of high-quality alfalfa leaf meal be produced and tested for evaluation in dairy, beef, aquaculture, poultry, and swine rations.

  7. Animal feed compositions containing phytase derived from transgenic alfalfa and methods of use thereof

    DOEpatents

    Austin-Phillips, Sandra; Koegel, Richard G.; Straub, Richard J.; Cook, Mark

    2001-01-01

    A value-added composition of matter containing plant matter from transgenic alfalfa which expresses exogenous phytase activity is disclosed. The phytase activity is a gene product of an exogenous gene encoding for phytase which has been stably incorporated into the genome of alfalfa plants. The transgenic alfalfa expresses phytase activity in nutritionally-significant amounts, thereby enabling its use in animal feeds to eliminate the need for phosphorous supplementation of livestock, poultry, and fish feed rations.

  8. Animal feed compositions containing phytase derived from transgenic alfalfa and methods of use thereof

    DOEpatents

    Austin-Phillips, Sandra; Koegel, Richard G.; Straub, Richard J.; Cook, Mark

    1999-01-01

    A value-added composition of matter containing plant matter from transgenic alfalfa which expresses exogenous phytase activity is disclosed. The phytase activity is a gene product of an exogenous gene encoding for phytase which has been stably incorporated into the genome of alfalfa plants. The transgenic alfalfa expresses phytase activity in nutritionally-significant amounts, thereby enabling its use in animal feeds to eliminate the need for phosphorous supplementation of livestock, poultry, and fish feed rations.

  9. Effects of the Insect Growth Regulator, Novaluron on Immature Alfalfa Leafcutting Bees, Megachile rotundata

    PubMed Central

    Hodgson, Erin W.; Pitts-Singer, Theresa L.; Barbour, James D.

    2011-01-01

    Alfalfa leafcutting bees, Megachile rotundata F. (Hymenoptera: Megachilidae), are the most common pollinators of alfalfa in the Pacific Northwest. Reports from users of M. rotundata in Idaho, Utah and Colorado have indicated exceptionally poor bee return from fields treated with novaluron to control Lygus spp. Our goal was to evaluate novaluron toxicity to immature M. rotundata using two different possible mechanisms of exposure. One goal was to assess immature mortality via treating nectar-pollen provisions and adults with novaluron. Immature M. rotundata mortality in all novaluron provision dosing treatments was significantly higher than the water or blank controls, providing evidence that novaluron is toxic to progeny in nest cells. The mean cumulative frequency showed that more eggs and 1st–2nd instars died compared to older instars. Female M. rotundata nested similarly in field cages during the field cage experiment; however, there was greater immature mortality in cages where females were fed sugar-water + novaluron compared to sugar-water only. Although females provided adequate provisions, there was a low percentage of egg hatch and larval development when females ingested novaluron before mating and nesting. Novaluron was also present in egg provision of bees collecting resources from novaluron-sprayed plants. At least 84% of progeny died when the females were allowed to mate and nest 24 hours after a novaluron application. Novaluron could be contributing to poor bee return in alfalfa grown for seed. Timely insecticide applications to suppress Lygus spp. is an important consideration to improve ongoing bee health. PMID:21539417

  10. Effects of the insect growth regulator, novaluron on immature alfalfa leafcutting bees, Megachile rotundata.

    PubMed

    Hodgson, Erin W; Pitts-Singer, Theresa L; Barbour, James D

    2011-01-01

    Alfalfa leafcutting bees, Megachile rotundata F. (Hymenoptera: Megachilidae), are the most common pollinators of alfalfa in the Pacific Northwest. Reports from users of M. rotundata in Idaho, Utah and Colorado have indicated exceptionally poor bee return from fields treated with novaluron to control Lygus spp. Our goal was to evaluate novaluron toxicity to immature M. rotundata using two different possible mechanisms of exposure. One goal was to assess immature mortality via treating nectar-pollen provisions and adults with novaluron. Immature M. rotundata mortality in all novaluron provision dosing treatments was significantly higher than the water or blank controls, providing evidence that novaluron is toxic to progeny in nest cells. The mean cumulative frequency showed that more eggs and 1st-2nd instars died compared to older instars. Female M. rotundata nested similarly in field cages during the field cage experiment; however, there was greater immature mortality in cages where females were fed sugar-water + novaluron compared to sugar-water only. Although females provided adequate provisions, there was a low percentage of egg hatch and larval development when females ingested novaluron before mating and nesting. Novaluron was also present in egg provision of bees collecting resources from novaluron-sprayed plants. At least 84% of progeny died when the females were allowed to mate and nest 24 hours after a novaluron application. Novaluron could be contributing to poor bee return in alfalfa grown for seed. Timely insecticide applications to suppress Lygus spp. is an important consideration to improve ongoing bee health. PMID:21539417

  11. Advancements in Root Growth Measurement Technologies and Observation Capabilities for Container-Grown Plants

    PubMed Central

    Judd, Lesley A.; Jackson, Brian E.; Fonteno, William C.

    2015-01-01

    The study, characterization, observation, and quantification of plant root growth and root systems (Rhizometrics) has been and remains an important area of research in all disciplines of plant science. In the horticultural industry, a large portion of the crops grown annually are grown in pot culture. Root growth is a critical component in overall plant performance during production in containers, and therefore it is important to understand the factors that influence and/or possible enhance it. Quantifying root growth has varied over the last several decades with each method of quantification changing in its reliability of measurement and variation among the results. Methods such as root drawings, pin boards, rhizotrons, and minirhizotrons initiated the aptitude to measure roots with field crops, and have been expanded to container-grown plants. However, many of the published research methods are monotonous and time-consuming. More recently, computer programs have increased in use as technology advances and measuring characteristics of root growth becomes easier. These programs are instrumental in analyzing various root growth characteristics, from root diameter and length of individual roots to branching angle and topological depth of the root architecture. This review delves into the expanding technologies involved with expertly measuring root growth of plants in containers, and the advantages and disadvantages that remain. PMID:27135334

  12. Relationship of crop radiance to alfalfa agronomic values

    NASA Technical Reports Server (NTRS)

    Tucker, C. J.; Elgin, J. H., Jr.; Mcmurtrey, J. E., III

    1980-01-01

    Red and photographic infrared spectral data of alfalfa were collected at the time of the third and fourth cuttings using a hand-held radiometer for the earlier alfalfa cutting. Significant linear and non-linear correlation coefficients were found between the spectral variables and plant height, biomass, forage water content, and estimated canopy cover. For the alfalfa of the later cutting, which had experienced a period of severe drought stress which limited growth, the spectral variables were found to be highly correlated with the estimated drought scores.

  13. Alfalfa stem feedstock for IGCC power system fuel

    SciTech Connect

    DeLong, M.M.; Onischak, M.; Schmid, M.; Wiant, B.; Oelke, E.

    1995-12-31

    A feasibility study was completed for an integrated gasification combined cycle (IGCC) electric power generation plant to operate in conjunction with an alfalfa processing plant that provides the gasification feedstock and a mid-level protein animal feed co-product. Alfalfa stem material was evaluated as a gasification feedstock. The leaf material was evaluated as a mid-level protein animal feed supplement. The alfalfa leaf-stem separation and power generation operations have dual and/or synergistic functions which contribute to a technically and economically compatible combination. The pressurized biomass gasification process selected is the IGT RENUGAS{trademark} system licensed to Tampella Power Corp. Adaptation of the air-blown gasification process to alfalfa stems results in low-Btu fuel gas suitable for combustion turbines. The gasification process is expected to obtain very high carbon conversion with low tar production, overcome ash agglomeration, and provide for control of volatile alkali species. A hot gas clean-up system removes particulate matter with a ceramic filter system. The collected ash residues are expected to be returned to the land that grew the alfalfa. The physical and chemical properties of the alfalfa feedstock were evaluated for the gasification process. The alfalfa char carbon-steam reaction, which is the slowest step in the complete conversion of biomass to gases, was measured and the char proved to have a high reactivity. Ash components were measured and evaluated in terms of agglomeration within the gasifier. Using this information, the alfalfa gasification conditions were predicted. A subsequent preliminary gasification test confirmed the alfalfa gasification conditions. To complete the engineering design of the IGCC system, additional testing is required, but the results to date are positive for a successful process.

  14. Environmental Stresses Increase Photosynthetic Disruption by Metal Oxide Nanomaterials in a Soil-Grown Plant.

    PubMed

    Conway, Jon R; Beaulieu, Arielle L; Beaulieu, Nicole L; Mazer, Susan J; Keller, Arturo A

    2015-12-22

    Despite an increasing number of studies over the past decade examining the interactions between plants and engineered nanomaterials (ENMs), very few have investigated the influence of environmental conditions on ENM uptake and toxicity, particularly throughout the entire plant life cycle. In this study, soil-grown herbaceous annual plants (Clarkia unguiculata) were exposed to TiO2, CeO2, or Cu(OH)2 ENMs at different concentrations under distinct light and nutrient levels for 8 weeks. Biweekly fluorescence and gas exchange measurements were recorded, and tissue samples from mature plants were analyzed for metal content. During peak growth, exposure to TiO2 and CeO2 decreased photosynthetic rate and CO2 assimilation efficiency of plants grown under high light and nutrient conditions, possibly by disrupting energy transfer from photosystem II (PSII) to the Calvin cycle. Exposure Cu(OH)2 particles also disrupted photosynthesis but only in plants grown under the most stressful conditions (high light, limited nutrient) likely by preventing the oxidation of a primary PSII reaction center. TiO2 and CeO2 followed similar uptake and distribution patterns with concentrations being highest in roots followed by leaves then stems, while Cu(OH)2 was present at highest concentrations in leaves, likely as ionic Cu. ENM accumulation was highly dependent on both light and nutrient levels and a predictive regression model was developed from these data. These results show that abiotic conditions play an important role in mediating the uptake and physiological impacts of ENMs in terrestrial plants. PMID:26505090

  15. Evaluation of hyperaccumulator plant species grown in metalliferous sites in Albania

    NASA Astrophysics Data System (ADS)

    Babani, F.; Civici, N.; Mullaj, A.; Kongjika, E.; Ylli, A.

    2007-04-01

    Heavy metal contamination of soils causes serious problems to our society. A small number of interesting plant species have been identified that can grow in soils containing high levels of heavy metals, and can also accumulate these metals to high concentrations in the shoot. The heavy metal contents in root, shoot, leaves and flowers of spontaneous plants grown in metalliferous sites in Albania together with the elemental composition of the native soils were determined by X-ray fluorescence spectrometry. Efficiency of photosynthetic apparatus of analyzed ecotypes was evaluated via chlorophyll fluorescence imaging during induction kinetics. Response of plant root system to the presence of metals, the available pools of metals to plants, effect of plant biomass to phytoextraction, photosynthetic pigment metabolism and chlorophyll fluorescence signature of leaves allowed to characterize hyperaccumulator properties and to detect the variation between selected ecotypes to heavy metal accumulation.

  16. Mycoleptodiscus Crown and Root Rot of Alfalfa: An Emerging Problem in Minnesota and Wisconsin?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mycoleptodiscus crown and root rot was observed on alfalfa plants from southeastern MN and southwestern WI during the summer of 2009. The disease was observed in new plantings and established stands. Although the disease has been known since the 1950's, it has not caused severe problems in alfalfa p...

  17. Roadside alfalfa: Innocent bystanders or conveyers of genetically-engineered traits?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Clumps of alfalfa are a common sight along roads and vacant lots in areas that grow alfalfa for hay or seed. So what role do feral roadside plants play in dispersing transgenes? Is there a risk that transgenic feral plants serve as reservoirs or conduits that might facilitate the movement of transg...

  18. Weed Research in Alfalfa Seed Production 2007

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control in alfalfa seed production is important to produce high quality and high yield of alfalfa seed. Herbicides were tested on a commercial field of alfalfa seed in central Washington in 2007. Flumioxzin slightly injured alfalfa when applied at 0.125 and 0.25 lb ai/a. to dormant alfalfa in M...

  19. Irrigation frequency alters nutrient uptake in container-grown Rhododendron plants grown with different rates of nitrogen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of irrigation frequency (same amount of water per day given at different times) on nutrient uptake of container-grown evergreen Rhododendron ‘P.J.M. Compact’ (PJM) and ‘English Roseum’ (ER) and deciduous Rhododendron ‘Gibraltar’ (AZ) grown with different rates of nitrogen (N) fertilize...

  20. Composition of volatile in micropropagated and field grown aromatic plants from Tuscany Islands.

    PubMed

    Pistelli, Laura; Noccioli, Cecilia; D'Angiolillo, Francesca; Pistelli, Luisa

    2013-01-01

    Aromatic plant species present in the natural Park of Tuscany Archipelago are used as flavoring agents and spices, as dietary supplements and in cosmetics and aromatherapy. The plants are usually collected from wild stands, inducing a depletion of the natural habitat. Therefore, micropropagation of these aromatic plants can play a role in the protection of the natural ecosystem, can guarantee a massive sustainable production and can provide standardized plant materials for diverse economical purposes. The aim of this study is to compare the volatile organic compounds produced by the wild plants with those from in vitro plantlets using headspace solid phase micro-extraction (HS-SPME) followed by capillary gas-chromatography coupled to mass spectrometry (GC-MS). Typical plants of this natural area selected for this work were Calamintha nepeta L., Crithmum maritimum L., Lavandula angustifolia L., Myrtus communis L., Rosmarinus officinalis L., Salvia officinalis L. and Satureja hortensis L. Different explants were used: microcuttings with vegetative apical parts, axillary buds and internodes. Sterilization percentage, multiplication rate and shoot length, as well as root formation were measured. The volatile aromatic profiles produced from in vitro plantlets were compared with those of the wild plants, in particular for C. maritimum, R. officinalis, S. officinalis and S. hortensis. This study indicated that the micropropagation technique can represent a valid alternative to produce massive and sterile plant material characterised by the same aromatic flavour as in the wild grown plants. PMID:23441303

  1. The relationship between growth and soluble sugar concentration of Aloe vera plants grown under three levels of irradiance

    SciTech Connect

    Paez, A.; Gebre, G.M.; Tschaplinski, T.J. )

    1994-06-01

    The CAM plant Aloe vera was vegetatively propagated and grown under three irradiances: full sun, partial and deep shade (30% and 10% of ambient light, respectively) to determine the effect on growth, biomass allocation, and sugar concentration. After one year, the plants were harvested to determine final dry weight and the sugar concentration of the leaf mucilaginous gel. Plants grown under full sun produced twice the total dry weight of those grown under partial shade, with the difference equally partitioned between the shoot and root. Plants grown under full sun also produced thicker leaves, and more numerous and large auxiliary shoots. The dry weight of plants grown under deep shade was 8.6% that of plants grown under full sun, which was directly proportional to the irradiance received. Partial shade increased the number and length of leaves produced on the primary shoot, but the allocation of carbon to roots was the lowest of all treatments. Partial shade reduced the total sugar concentration of the leaf gel matrix to 34% that of plants under full sun, due to reductions in all sugars measured. Glucose was the most abundant soluble sugar, with its relative contribution to the total pool increasing under shade. In summary, the proportional effects of partial shading were greater on soluble sugar concentrations than on the total plant biomass produced.

  2. Occurrence of Transgenic Feral Alfalfa (Medicago sativa subsp. sativa L.) in Alfalfa Seed Production Areas in the United States

    PubMed Central

    Greene, Stephanie L.; Kesoju, Sandya R.; Martin, Ruth C.; Kramer, Matthew

    2015-01-01

    The potential environmental risks of transgene exposure are not clear for alfalfa (Medicago sativa subsp. sativa), a perennial crop that is cross-pollinated by insects. We gathered data on feral alfalfa in major alfalfa seed-production areas in the western United States to (1) evaluate evidence that feral transgenic plants spread transgenes and (2) determine environmental and agricultural production factors influencing the location of feral alfalfa, especially transgenic plants. Road verges in Fresno, California; Canyon, Idaho; and Walla Walla, Washington were surveyed in 2011 and 2012 for feral plants, and samples were tested for the CP4 EPSPS protein that conveys resistance to glyphosate. Of 4580 sites surveyed, feral plants were observed at 404 sites. Twenty-seven percent of these sites had transgenic plants. The frequency of sites having transgenic feral plants varied among our study areas. Transgenic plants were found in 32.7%, 21.4.7% and 8.3% of feral plant sites in Fresno, Canyon and Walla Walla, respectively. Spatial analysis suggested that feral populations started independently and tended to cluster in seed and hay production areas, places where seed tended to drop. Significant but low spatial auto correlation suggested that in some instances, plants colonized nearby locations. Neighboring feral plants were frequently within pollinator foraging range; however, further research is needed to confirm transgene flow. Locations of feral plant clusters were not well predicted by environmental and production variables. However, the likelihood of seed spillage during production and transport had predictive value in explaining the occurrence of transgenic feral populations. Our study confirms that genetically engineered alfalfa has dispersed into the environment, and suggests that minimizing seed spillage and eradicating feral alfalfa along road sides would be effective strategies to minimize transgene dispersal. PMID:26699337

  3. Tolerance of wheat and lettuce plants grown on human mineralized waste to high temperature stress

    NASA Astrophysics Data System (ADS)

    Ushakova, Sofya A.; Tikhomirov, Alexander A.; Shikhov, Valentin N.; Gros, Jean-Bernard; Golovko, Tamara K.; Dal'ke, Igor V.; Zakhozhii, Ilya G.

    2013-06-01

    The main objective of a life support system for space missions is to supply a crew with food, water and oxygen, and to eliminate their wastes. The ultimate goal is to achieve the highest degree of closure of the system using controlled processes offering a high level of reliability and flexibility. Enhancement of closure of a biological life support system (BLSS) that includes plants relies on increased regeneration of plant waste, and utilization of solid and liquid human wastes. Clearly, the robustness of a BLSS subjected to stress will be substantially determined by the robustness of the plant components of the phototrophic unit. The aim of the present work was to estimate the heat resistance of two plants (wheat and lettuce) grown on human wastes. Human exometabolites mineralized by hydrogen peroxide in an electromagnetic field were used to make a nutrient solution for the plants. We looked for a possible increase in the heat tolerance of the wheat plants using changes in photosynthetically active radiation (PAR) intensity during heat stress. At age 15 days, plants were subjected to a rise in air temperature (from 23 ± 1 °C to 44 ± 1 °С) under different PAR intensities for 4 h. The status of the photosynthetic apparatus of the plants was assessed by external СО2 gas exchange and fluorescence measurements. The increased irradiance of the plants during the high temperature period demonstrated its protective action for both the photosynthetic apparatus of the leaves and subsequent plant growth and development. The productivity of the plants subjected to temperature changes at 250 W m-2 of PAR did not differ from that of controls, whereas the productivity of the plants subjected to the same heat stress but in darkness was halved.

  4. Internode length in pisum: do the internode length genes effect growth in dark-grown plants?

    PubMed

    Reid, J B

    1983-07-01

    Internode length in light-grown peas (Pisum sativum L.) is controlled by the interaction of genes occupying at least five major loci, Le, La, Cry, Na, and Lm. The present work shows that the genes at all of the loci examined (Le, Cry, and Na) also exert an effect on internode length in plants grown in complete darkness. Preliminary results using pure lines were verified using either segregating progenies or near isogenic lines. The major cause of the differences was due to a change in the number of cells per internode rather than to an alteration of the cell length. Since the genes occupying at least two of these loci, Le and Na, have been shown to be directly involved with gibberellin metabolism, it appears that gibberellins are not only essential for elongation in the dark but are limiting for elongation in the nana (extremely short, na), dwarf (Na le), and tall (Na Le) phenotypes. These results are supported by the large inhibitory effects of AMO 1618 treatments on stem elongation in dwarf and tall lines grown in the dark and the fact that applied gibberellic acid could overcome this inhibition and greatly promote elongation in a gibberellin-deficient na line. It is clear that the internode length genes, and in particular the alleles at the Le locus, are not acting by simply controlling the sensitivity of the plant to light. PMID:16663081

  5. High relative humidity increases yield, harvest index, flowering, and gynophore growth of hydroponically grown peanut plants

    NASA Technical Reports Server (NTRS)

    Mortley, D. G.; Bonsi, C. K.; Loretan, P. A.; Hill, W. A.; Morris, C. E.

    2000-01-01

    Growth chamber experiments were conducted to study the physiological and growth response of peanut (Arachis hypogaea L.) to 50% and 85% relative humidity (RH). The objective was to determine the effects of RH on pod and seed yield, harvest index, and flowering of peanut grown by the nutrient film technique (NFT). 'Georgia Red' peanut plants (14 days old) were planted into growth channels (0.15 x 0.15 x 1.2 m). Plants were spaced 25 cm apart with 15 cm between channels. A modified half-Hoagland solution with an additional 2 mM Ca was used. Solution pH was maintained between 6.4 and 6.7, and electrical conductivity (EC) ranged between 1100 and 1200 microS cm-1. Temperature regimes of 28/22 degrees C were maintained during the light/dark periods (12 hours each) with photosynthetic photon flux (PPF) at canopy level of 500 micromoles-m-2s-1. Foliage and pod fresh and dry weights, total seed yield, harvest index (HI), and seed maturity were greater at high than at low RH. Plants grown at 85% RH had greater total and individual leaflet area and stomatal conductance, flowered 3 days earlier and had a greater number of flowers reaching anthesis. Gynophores grew more rapidly at 85% than at 50% RH.

  6. EFFECTS OF OZONE AND WATER STRESS ON CANOPY TEMPERATURE, WATER USE, AND WATER USE EFFICIENCY OF ALFALFA

    EPA Science Inventory

    Ozone (O3) and soil water deficit are two environmental stresses that significantly affect the growth and yield of alfalfa. However, little is known of the responses of field-grown alfalfa to O3, and the effects of the interaction between O3 and water stress on canopy temperature...

  7. Chalkbrood Transmission in the Alfalfa Leafcutting Bee: The Impact of Disinfecting Bee Cocoons in Loose Cell Management Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A good understanding of pathogen transmission in a host population should illuminate methods for disease prevention and control. A case in point for this is the alfalfa leafcutting bee (Megachile rotundata), a solitary bee which is used extensively for pollination of alfalfa grown for seed. Propaga...

  8. A native ground nesting bee, Nomia melanderi, sustainably managed to pollinate alfalfa across an intensively agricultural landscape

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technical Abstract: The world’s only intensively managed ground-nesting bee, the alkali bee (Nomia melanderi Cockerell), has been used for >50 years as an effective pollinator of alfalfa (Medicago sativa L.) grown for seed across the western USA. Throughout the 240 km2 Touchet Valley alfalfa farmin...

  9. Drought responses of Arrhenatherum elatius grown in plant assemblages of varying species richness

    NASA Astrophysics Data System (ADS)

    Otieno, Dennis; Kreyling, Juergen; Purcell, Andrew; Herold, Nadine; Grant, Kerstin; Tenhunen, John; Beierkuhnlein, Carl; Jentsch, Anke

    2012-02-01

    Evidence exists that plant community diversity influences productivity of individual members and their resistance and resilience during and after perturbations. We simulated drought within the long-term EVENT experimental site in the Ecological-Botanical Garden, University of Bayreuth to understand how Arrhenatherum elatius (L.) responds to water stress when grown in three different plant assemblages. The set up consisted of five replications for each factorial combination of drought and plant assemblages differing in functional diversity. Leaf water potential (ΨL), leaf gas exchange, natural δ13C, plant biomass and cover were measured. Imposed drought had different effects on A. elatius, depending on plant assemblage composition. Severe water stress was however, avoided by slowing down the rate of decline in ΨL, and this response was modified by community composition. High ΨL was associated with high stomatal conductance and leaf photosynthesis. Biomass production of A. elatius increased due to drought stress only in the least diverse assemblage, likely due to increased tillering and competitive advantage against neighbors in the drought-treated plants. Our results indicate that beneficial traits among plant species in a community may be responsible for the enhanced capacity to survive drought stress. Resistance to drought may, therefore, not be linked to species richness, but rather to the nature of interaction that exists between the community members.

  10. Lignification in young plant seedlings grown on earth and aboard the Space Shuttle

    NASA Technical Reports Server (NTRS)

    Cowles, Joe R.; Lemay, R.; Jahns, G.; Scheld, W. H.; Peterson, C.

    1989-01-01

    The Space Shuttle era has provided an opportunity for investigators to conduct experiments in a microgravity environment. Two Shuttle flights, STS-3 and STS-51F, each contained an experiment designed principally to determine whether young plant seedlings exposed to microgravity had reduced lignin content in comparison to seedlings grown at one gravity. Three different plant species, pine, oats, and mung beans, were exposed for eight days to the microgravity environment of the Shuttle. The lignin content of in-flight seedlings was less than the control seedlings in all seven sets of seedlings included in these two experiments. In five sets of seedlings, the reduction in lignin content in flight seedlings ranged from 6 to 24 percent and was statistically significant. In addition, the activity of two enzymes involved in lignin synthesis, phenylalanine ammonia lyase and peroxidase, were significantly reduced in pine seedlings. It was therefore concluded that microgravity, as perceived by young plant seedlings, results in reduced lignin synthesis.

  11. PLUTONIUM UPTAKE BY PLANTS FROM SOIL CONTAINING PLUTONIUM-238 DIOXIDE PARTICLES

    EPA Science Inventory

    Three plant species--alfalfa, lettuce, and radishes were grown in soils contaminated with plutonium-238 dioxide (238)PuO2 at concentrations of 23, 69, 92, and 342 nanocuries per gram (nCi/g). The length of exposure varied from 60 days for the lettuce and radishes to 358 days for ...

  12. Toxic hepatopathy and photosensitization in cattle fed moldy alfalfa hay.

    PubMed

    Scruggs, D W; Blue, G K

    1994-01-15

    Cattle in 2 herds developed type-3 photosensitization after eating moldy alfalfa hay. Clinical signs included severe epidermal necrosis of unpigmented skin and marked decrease of milk production (herd 1). One herd had 18% mortality. Values for serum gamma-glutamyltransferase, lactate dehydrogenase, aspartate transaminase, and serum bilirubin were high in affected cows. Biliary epithelial degeneration and necrosis affecting the smaller bile ductules is the most consistent histologic lesion. Biliary hyperplasia, early portal fibroplasia, hepatocellular vacuolar degeneration and necrosis, and cholestasis were commonly seen. Mold growth on the alfalfa hay associated with prolonged wet weather prior to harvest was common to both herds. The cases reported here document hepatoxicosis and photosensitization associated with feeding moldy alfalfa hay grown in southeastern United States. PMID:7908282

  13. Biological Relationship of Meloidogyne hapla Populations to Alfalfa Cultivars

    PubMed Central

    Griffin, G. D.; Gray, F. A.

    1995-01-01

    Greenhouse and growth chamber studies were established to determine if there are pathological and physiological differences among Meloidogyne hapla populations from California (CA), Nevada (NV), Utah (UT), and Wyoming (WY) on alfalfa cultivars classified as resistant or susceptible to root-knot nematodes. In the greenhouse, plant survival was not consistent with resistance classifications. While all highly resistant Nevada Synthetic germplasm (Nev Syn XX) plants survived inoculation with all nematode populations, two cultivars classified as moderately resistant ('Chief' and 'Kingstar') survived (P ≤ 0.05) inoculation with M. hapla populations better than did 'Lobo' cultivar, which is classified as resistant. Plant growth of Nev Syn XX was suppressed by only the CA population, whereas growth of the other alfalfa cultivars classified as M. hapla resistant or moderately resistant was suppressed by all nematode populations. Excluding Nev Syn XX, all alfalfa cultivars were severely galled and susceptible to all nematode populations. Except for Nev Syn XX, reproduction did not differ among the nematode populations on alfalfa cultivars. Nev Syn XX was not as favorable a host to CA as were the other cultivars; but, it was a good host (reproductive factor [Rf] = 37). Temperature affected plant resistance; the UT and WY populations were more pathogenic at 15-25 C, and CA was more pathogenic at 30 C. Nev Syn XX was susceptible to all nematode populations, except for CA, at only 30 C, and all other alfalfa cultivars were susceptible to all nematode populations at all temperatures. PMID:19277299

  14. Transgene silencing of sucrose synthase in alfalfa (Medicago sativa L.) stem vascular tissue suggests a role for invertase in cell wall cellulose synthesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L.) plants were transformed with two constructs: (1) a truncated phosphoenolpyruvate carboxylase promoter isolated from alfalfa nodules (PEPC-4) fused to GUS; and (2) PEPC-4 fused with sucrose synthase (SUS) isolated from alfalfa nodules. Histochemical staining for GUS in st...

  15. Impact of alfalfa on soil and water quality

    SciTech Connect

    Sharma, P.; Moncrief, J.; Gupta, S.

    1997-10-30

    Dominance of row crop agriculture in rolling landscapes of western and Southwestern Minnesota is identified as a primary, non-point source of sediments and associated pollutants reaching the Minnesota River. Currently as a biomass energy project, alfalfa is being promoted in western Minnesota to harvest the leaves for animal feed and stems to generate electricity. As a perennial, leguminous crop grown with minimum inputs, introduction of alfalfa in row cropped lands has potential to improve both in-situ soil productivity and downstream water quality. A field study was initiated in 1996 to compare the volume of runoff and pollutants coming from alfalfa an com-soybean fields in western Minnesota. Two pair of alfalfa and corn-soybean watersheds were instrumented at Morris in the Fall of 1996 to measure rainfall, runoff, and sample water for sediment load, phosphorus, nitrogen, biochemical oxygen demand, and chemical oxygen demand. Simulated rainfall-runoff experiments were conducted on an existing crop rotation - input management study plots at Lamberton to evaluate soil quality effects of the inclusion of alfalfa in a corn-soybean rotation under manure and fertilization management schemes. Alfalfa soil water use as a function of frequency of harvest was also monitored at Morris to evaluate the effect of cutting schedule on soil water use. During the growing season of 1997, alfalfa under a two-cut management scheme used about 25-mm (an inch) more soil water than under a three-cut schedule. The mean differences between the treatments were not significant. The conclusions drawn in this report come from analysis of data collected during one winter-summer hydrologic and crop management cycle. Continued observations through a period of at least 3-5 years is recommended to improve the instrumentation robustness and discern the variability due to climate, soil, and crop management factors.

  16. Physiological Responses of Soybean Plants Grown in a Nitrogen-Free or Energy Limited Environment 1

    PubMed Central

    Zhu, Yu-xian; Schubert, Karel R.; Kohl, Daniel H.

    1991-01-01

    Soybean (Glycine max [L.] Merr.) seedlings grown in the absence of combined N and in an Ar:O2 (79:21, volume/volume) atmosphere had greater seedling and nodule mass, threefold higher acetylene reducing activity per gram fresh weight nodules, no observable increase in nitrogenase Fe-protein, and a higher energy charge than did control plants. A sharp fall in acetylene reducing activity and energy charge accompanying stem-girdling was prevented by exogenous succinate, a result consistent with a path from the roots to the nodule other than via the phloem. ImagesFigure 1 PMID:16668170

  17. Nitrogen fertilizer improves boron phytoextraction by Brassica juncea grown in contaminated sediments and alleviates plant stress.

    PubMed

    Giansoldati, Virginia; Tassi, Eliana; Morelli, Elisabetta; Gabellieri, Edi; Pedron, Francesca; Barbafieri, Meri

    2012-06-01

    In this study we evaluated the effect of different fertilizer treatments on Brassica plants grown on boron-contaminated sediments. Experiments were conducted in the laboratory and on the lysimeter scale. At laboratory scale (microcosm), five different fertilizers were tested for a 35-d period. On the lysimeter scale, nitrogen fertilization was tested at three different doses and plants were allowed to grow until the end of the vegetative phase (70 d). Results showed that nitrogen application had effectively increased plant biomass production, while B uptake was not affected. Total B phytoextracted increased three-fold when the highest nitrogen dose was applied. Phytotoxicity on Brassica was evaluated by biochemical parameters. In plants grown in unfertilized B-contaminated sediments, the activity of antioxidant enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX) and pyrogallol peroxidase (PPX) increased, whereas catalase (CAT) decreased with respect to control plants. Addition of N progressively mitigated the alteration of enzymatic activity, thus suggesting that N can aid in alleviating B-induced oxidative stress. SOD activity was restored to control levels just at the lowest N treatment, whereas the CAT inhibition was partially restored only at the highest one. N application also lowered the B-induced increase in APX and PPX activities. Increased glutathione reductase activity indicated the need to restore the oxidative balance of glutathione. Data also suggest a role of glutathione and phytochelatins in B defense mechanisms. Results suggest that the nitrogen fertilizer was effective in improving B phytoextraction by increasing Brassica biomass and by alleviating B-induced oxidative stress. PMID:22382070

  18. Validating Topdressed K Fertilizer Recommendations in an Alfalfa-Corn Rotation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potassium (K) fertilizer prices are higher than average and may reduce bottom line returns for alfalfa growers. Potassium supports plant stress tolerance and plays a critical role in alfalfa yield by moving sugars from shoots to roots. Current University of Minnesota recommendations are to apply bet...

  19. Gain from selection for 16- and 96-h in vitro NDF digestibility of alfalfa stems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is a high-quality forage, but stems are high in NDF and of limited digestibility. A gain from selection study with alfalfa populations selected for divergent in vitro NDF digestibility (IVNDFD) was planted at St. Paul and Becker, MN. Two cycles of selection were conducted starting with a bas...

  20. Responses of Medicago sativa and M. falcata type alfalfas to different defoliation times and grass competition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Incorporating alfalfa into rangelands can enhance the quantity and quality of forage production. We evaluated the impact of defoliation timing and selective defoliation on two grazing- (Anik and SCMF 3713) and one hay-type alfalfas (Vernal) near Mandan, North Dakota, USA. Entries were space-plante...

  1. Alfalfa root health and disease management: a foundation for maximizing production potential and stand life

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Beneath the lush green leaves of an alfalfa plant is a surprisingly large root system. It is this large root system that is at the heart of the valuable traits of the crop. Many factors influence root growth and root health of alfalfa, but diseases can be especially important. Several different dise...

  2. Mapping fall dormancy and winter injury in tetraploid alfalfa (Medicago sativa L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is a widely planted perennial forage crop. Dormancy in autumn (fall dormancy) is generally negatively correlated with winter injury in alfalfa. To understand the genetic basis of the two traits, we identified quantitative trait loci (QTL) controlling autumn growth and winter injury using a...

  3. Economics of growth regulator treatment of alfalfa seed for interseeding into silage corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous studies have focused on interseeding of alfalfa into corn for use as a temporary cover crop rather than as a means of jump-starting alfalfa production after corn. In ongoing field studies, we are evaluating whether plant growth regulators (PGR) may be used to aid the establishment of inters...

  4. Effect of electromagnetic stimulation of alfalfa seeds

    NASA Astrophysics Data System (ADS)

    Ćwintal, M.; Dziwulska-Hunek, A.

    2013-12-01

    In the conducted experiments the effect of presowing He-Ne laser light, magnetic field stimulation or the combination of these two factors of alfalfa seeds on the field emergence, structure and yields in the year of sowing and during three following years of full land use were studied. The examined factors had a significant effect on the number of shoots per 1 m2, plant height, mass of shoots, fresh and dry mass. Electromagnetic stimulation resulted in a significant increase in alfalfa seeds emergence (from 35% - control to 47.8% - magnetic field), number of shoots per 1m2 (from 608 - control to 813 - laser light in cut), but a decrease of the mass of the shoots (from 0.61 g - control to 0.50 g - laser light).

  5. Relationship of red and photographic infrared spectral radiances to alfalfa biomass, forage water content, percentage canopy cover, and severity of drought stress

    NASA Technical Reports Server (NTRS)

    Tucker, C. J.; Elgin, J. H., Jr.; Mcmurtrey, J. E., III

    1979-01-01

    Red and photographic infrared spectral data were collected using a handheld radiometer for two cuttings of alfalfa. Significant linear and non-linear correlation coefficients were found between the spectral variables and plant height, biomass, forage water content, and estimated canopy cover for the earlier alfalfa cutting. The alfalfa of later cutting experienced a period of severe drought stress which limited growth. The spectral variables were found to be highly correlated with the estimated drought scores for this alfalfa cutting.

  6. Alfalfa diseases 101: diagnosing common and emerging disease problems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    More than 50 pathogens have been identified that cause significant damage to alfalfa and prevent it from reaching its full potential for producing high yields of quality forage. There has been excellent progress by plant breeders and plant pathologists in developing cultivars with multiple disease a...

  7. Brown Root Rot of Alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This bulletin describes the disease of alfalfa called brown root rot (BRR) including: the disease symptoms, the fungal pathogen and its biology, its distribution, and disease management. Since the 1920s, BRR has been regarded as an important disease of forage legumes, including alfalfa, in northern ...

  8. Plant regeneration and cellular behaviour studies in Celosia cristata grown in vivo and in vitro.

    PubMed

    Taha, Rosna Mat; Wafa, Sharifah Nurashikin

    2012-01-01

    Tissue culture studies of Celosia cristata were established from various explants and the effects of various hormones on morphogenesis of this species were examined. It was found that complete plant regeneration occurred at highest percentage on MS medium supplemented with 2.0 mg/L NAA and 1.5 mg/L BAP, with the best response showed by shoot explants. In vitro flowering was observed on MS basal medium after six weeks. The occurrence of somaclonal variation and changes in cellular behavior from in vivo and in vitro grown plants were investigated through cytological studies and image analysis. It was observed that Mitotic Index (MI), mean chromosome numbers, and mean nuclear to cell area ratio of in vitro root meristem cells were slightly higher compared to in vivo values. However, in vitro plants produced lower mean cell areas but higher nuclear areas when compared to in vivo plants. Thus, no occurrence of somaclonal variation was detected, and this was supported by morphological features of the in vitro plants. PMID:22593677

  9. Plant Regeneration and Cellular Behaviour Studies in Celosia cristata Grown In Vivo and In Vitro

    PubMed Central

    Taha, Rosna Mat; Wafa, Sharifah Nurashikin

    2012-01-01

    Tissue culture studies of Celosia cristata were established from various explants and the effects of various hormones on morphogenesis of this species were examined. It was found that complete plant regeneration occurred at highest percentage on MS medium supplemented with 2.0 mg/L NAA and 1.5 mg/L BAP, with the best response showed by shoot explants. In vitro flowering was observed on MS basal medium after six weeks. The occurrence of somaclonal variation and changes in cellular behavior from in vivo and in vitro grown plants were investigated through cytological studies and image analysis. It was observed that Mitotic Index (MI), mean chromosome numbers, and mean nuclear to cell area ratio of in vitro root meristem cells were slightly higher compared to in vivo values. However, in vitro plants produced lower mean cell areas but higher nuclear areas when compared to in vivo plants. Thus, no occurrence of somaclonal variation was detected, and this was supported by morphological features of the in vitro plants. PMID:22593677

  10. Phytohormone profile in Lactuca sativa and Brassica oleracea plants grown under Zn deficiency.

    PubMed

    Navarro-León, Eloy; Albacete, Alfonso; Torre-González, Alejandro de la; Ruiz, Juan M; Blasco, Begoña

    2016-10-01

    Phytohormones, structurally diverse compounds, are involved in multiple processes within plants, such as controlling plant growth and stress response. Zn is an essential micronutrient for plants and its deficiency causes large economic losses in crops. Therefore, the purpose of this study was to analyse the role of phytohormones in the Zn-deficiency response of two economically important species, i.e. Lactuca sativa and Brassica oleracea. For this, these two species were grown hydroponically with different Zn-application rates: 10 μM Zn as control and 0.1 μM Zn as deficiency treatment and phytohormone concentration was determined by U-HPLC-MS. Zn deficiency resulted in a substantial loss of biomass in L. sativa plants that was correlated with a decline in growth-promoting hormones such as indole-3-acetic acid (IAA), cytokinins (CKs), and gibberellins (GAs). However these hormones increased or stabilized their concentrations in B. oleracea and could help to maintain the biomass in this species. A lower concentration of stress-signaling hormones such as ethylene precursor aminocyclopropane-1-carboxylic acid (ACC), abscisic acid (ABA), salicylic acid (SA) and jasmonic acid (JA) and also CKs might be involved in Zn uptake in L. sativa while a rise in GA4, isopentenyl adenine (iP), and ACC and a fall in JA and SA might contribute to a better Zn-utilization efficiency (ZnUtE), as observed in B. oleracea plants. PMID:27543253

  11. Alfalfa subsp. sativa by falcata intersubspecific semi-hybrid seed production using alfalfa leafcutter bees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intersubspecific sativa by falcata alfalfa (Medicago sativa L.) hybrids offer a means of improving alfalfa dry matter yields. The alfalfa leafcutter bee (Megachile rotundata F.) is a major pollinator used in alfalfa seed production in North America. Alfalfa leafcutter bees have a pollinator prefer...

  12. Multiwalled carbon nanotubes in alfalfa and wheat: toxicology and uptake

    PubMed Central

    Miralles, Pola; Johnson, Errin; Church, Tamara L.; Harris, Andrew T.

    2012-01-01

    Data on the bioavailability and toxicity of carbon nanotubes (CNTs) in the environment, and, in particular, on their interactions with vascular plants, are limited. We investigated the effects of industrial-grade multiwalled CNTs (75 wt% CNTs) and their impurities on alfalfa and wheat. Phytotoxicity assays were performed during both seed germination and seedling growth. The germinations of both species were tolerant of up to 2560 mg l−1 CNTs, and root elongation was enhanced in alfalfa and wheat seedlings exposed to CNTs. Remarkably, catalyst impurities also enhanced root elongation in alfalfa seedlings as well as wheat germination. Thus the impurities, not solely the CNTs, impacted the plants. CNT internalization by plants was investigated using electron microscopy and two-dimensional Raman mapping. The latter showed that CNTs were adsorbed onto the root surfaces of alfalfa and wheat without significant uptake or translocation. Electron microscopy investigations of internalization were inconclusive owing to poor contrast, so Fe3O4-functionalized CNTs were prepared and studied using energy-filter mapping of Fe3O4. CNTs bearing Fe3O4 nanoparticles were detected in the epidermis of one wheat root tip only, suggesting that internalization was possible but unusual. Thus, alfalfa and wheat tolerated high concentrations of industrial-grade multiwalled CNTs, which adsorbed onto their roots but were rarely taken up. PMID:22977097

  13. Predicting the effects of gas diffusivity on photosynthesis and transpiration of plants grown under hypobaria

    NASA Astrophysics Data System (ADS)

    Gohil, Hemant L.; Correll, Melanie J.; Sinclair, Thomas

    2011-01-01

    As part of a Bio-regenerative Life Support System (BLSS) for long-term space missions, plants will likely be grown at reduced pressure. This low pressure will minimize structural requirements for growth chambers on missions to the Moon or Mars. However, at reduced pressures the diffusivity of gases increases. This will affect the rates at which CO2 is assimilated and water is transpired through stomata. To understand quantitatively the possible effects of reduced pressure on plant growth, CO2 and H2O transport were calculated for atmospheres of various total pressures (101, 66, 33, 22, 11 kPa) and CO2 concentrations (0.04, 0.1 and 0.18 kPa). The diffusivity of a gas is inversely proportional to total pressure and shows dramatic increases at pressures below 33 kPa (1/3 atm). A mathematical relationship based on the principle of thermodynamics was applied to low pressure conditions and can be used for calculating the transpiration and photosynthesis of plants grown in hypobaria. At 33 kPa total pressure, the stomatal conductance increases by a factor of three with the boundary layer conductance increasing by a factor of ˜1.7, since the leaf conductance is a function of both stomatal and the boundary layer conductance, the overall conductance will increase resulting in significantly higher levels of transpiration as the pressure drops. The conductance of gases is also regulated by stomatal aperture in an inverse relationship. The higher CO2 concentration inside the leaf air space during low pressure treatments may result in higher CO2 assimilation and partial stomata closure, resulting in a decrease in transpiration rate. The results of this analysis offer guidelines for experiments in pressure and high CO2 environments to establish ideal conditions for minimizing transpiration and maximizing the plant biomass yield in BLSS.

  14. Wool-waste as organic nutrient source for container-grown plants

    SciTech Connect

    Zheljazkov, Valtcho D. Stratton, Glenn W.; Pincock, James; Butler, Stephanie; Jeliazkova, Ekaterina A.; Nedkov, Nedko K.; Gerard, Patrick D.

    2009-07-15

    A container experiment was conducted to test the hypothesis that uncomposted wool wastes could be used as nutrient source and growth medium constituent for container-grown plants. The treatments were: (1) rate of wool-waste application (0 or unamended control, 20, 40, 80, and 120 g of wool per 8-in. pot), (2) growth medium constituents [(2.1) wool plus perlite, (2.2) wool plus peat, and (2.3) wool plus peat plus perlite], and (3) plant species (basil and Swiss chard). A single addition of 20, 40, 80, or 120 g of wool-waste to Swiss chard (Beta vulgaris L.) and basil (Ocimum basilicum L.) in pots with growth medium provided four harvests of Swiss chard and five harvests of basil. Total basil yield from the five harvests was 1.6-5 times greater than the total yield from the unamended control, while total Swiss chard yield from the four harvests was 2-5 times greater relative to the respective unamended control. The addition of wool-waste to the growth medium increased Swiss chard and basil tissue N, and NO{sub 3}-N and NH{sub 4}-N in growth medium relative to the unamended control. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) microanalysis of wool fibers sampled at the end of the experiments indicated various levels of decomposition, with some fibers retaining their original surface structure. Furthermore, most of the wool fibers' surfaces contained significant concentrations of S and much less N, P, or K. SEM/EDX revealed that some plant roots grow directly on wool-waste fibers suggesting either (1) root directional growth towards sites with greater nutrient concentration and/or (2) a possible role for roots or root exudates in wool decomposition. Results from this study suggest that uncomposted wool wastes can be used as soil amendment, growth medium constituent, and nutrient source for container-grown plants.

  15. A Method to Teach Age-Specific Demography with Field Grown Rapid Cycling "Brassica rapa" (Wisconsin Fast Plants)

    ERIC Educational Resources Information Center

    Kelly, Martin G.; Terrana, Sebastian

    2004-01-01

    In this paper, we demonstrate that rapid cycling "Brassica rapa" (Wisconsin Fast Plants) can be used in inquiry-based, student ecological fieldwork. We are the first to describe age-specific survival for field-grown Fast Plants and identify life history traits associated with individual survival. This experiment can be adapted by educators as a…

  16. Thermodynamic and structural properties of tuber starches from transgenic potato plants grown in vitro and in vivo.

    PubMed

    Wasserman, Luybov A; Sergeev, Andrey I; Vasil'ev, Viktor G; Plashchina, Irina G; Aksenova, Nina P; Konstantinova, Tatyana N; Golyanovskaya, Svetlana A; Sergeeva, Lidiya I; Romanov, Georgy A

    2015-07-10

    Potato plants harboring Phytochrome B (PHYB) gene from Arabidopsis thaliana or rol genes from Agrobacterium rhizogenes were used to study the effect of transgene expression on structure and properties of starch in tubers. Thermodynamic characteristics of starch (melting temperature, enthalpy of melting, thickness of crystalline lamellae) were shown to be variable depending on the transgene expression and plant culturing mode: in vitro or in soil. The expression of rolB or rolC genes in in vitro cultured plants evoked opposite effects on starch melting temperature and crystalline lamellae thickness. AtPHYB or rolB expression in the soil-grown potato led to the formation of more defective or more ordered starch structures, respectively, in comparison with starches of the same lines grown in vitro. On the whole, our study revealed genotype-dependent differences between starches extracted from tubers of in vitro or in vivo grown plants. PMID:25857977

  17. Effect of crop development on biogenic emissions from plant populations grown in closed plant growth chambers

    NASA Technical Reports Server (NTRS)

    Batten, J. H.; Stutte, G. W.; Wheeler, R. M.

    1995-01-01

    The Biomass Production Chamber at John F. Kennedy Space Center is a closed plant growth chamber facility that can be used to monitor the level of biogenic emissions from large populations of plants throughout their entire growth cycle. The head space atmosphere of a 26-day-old lettuce (Lactuca sativa cv. Waldmann's Green) stand was repeatedly sampled and emissions identified and quantified using GC-mass spectrometry. Concentrations of dimethyl sulphide, carbon disulphide, alpha-pinene, furan and 2-methylfuran were not significantly different throughout the day; whereas, isoprene showed significant differences in concentration between samples collected in light and dark periods. Volatile organic compounds from the atmosphere of wheat (Triticum aestivum cv. Yecora Rojo) were analysed and quantified from planting to maturity. Volatile plant-derived compounds included 1-butanol, 2-ethyl-1-hexanol, nonanal, benzaldehyde, tetramethylurea, tetramethylthiourea, 2-methylfuran and 3-methylfuran. Concentrations of volatiles were determined during seedling establishment, vegetative growth, anthesis, grain fill and senescence and found to vary depending on the developmental stage. Atmospheric concentrations of benzaldehyde and nonanal were highest during anthesis, 2-methylfuran and 3-methylfuran concentrations were greatest during grain fill, and the concentration of the tetramethylurea peaked during senescence.

  18. Lead induced changes in phosphorylation of PSII proteins in low light grown pea plants.

    PubMed

    Wioleta, Wasilewska; Anna, Drożak; Ilona, Bacławska; Kamila, Kąkol; Elżbieta, Romanowska

    2015-02-01

    Light-intensity and redox-state induced thylakoid proteins phosphorylation involved in structural changes and in regulation of protein turnover. The presence of heavy metal ions triggers a wide range of cellular responses including changes in plant growth and photosynthesis. Plants have evolved a number of mechanisms to protect photosynthetic apparatus. We have characterized the effect of lead on PSII protein phosphorylation in pea (Pisum sativum L.) plants grown in low light conditions. Pb ions affected only slightly photochemical efficiency of PSII and had no effect on organization of thylakoid complexes. Lead activated strongly phosphorylation of PSII core D1 protein and dephosphorylation of this protein did not proceed in far red light. D1 protein was also not degraded in this conditions. However, phosphorylation of LHCII proteins was not affected by lead. These results indicate that Pb(2+) stimulate the phosphorylation of PSII core proteins and by disturbing the disassembly of supercomplexes play a role in PSII repair mechanism. LHCII phosphorylation could control the distribution of energy between the photosystems in low light conditions. This demonstrates that plants may respond to heavy metals by induction different pathways responsible for protein protection under stress conditions. PMID:25491575

  19. Stress responses in alfalfa (Medicago sativa L. )

    SciTech Connect

    Kessmann, H.; Edwards, R.; Dixon, R.A. ); Geno, P.W. )

    1990-09-01

    The isoflavonoid conjugates medicarpin-3-O-glucoside-6{double prime}-O-malonate (MGM), afrormosin-7-O-glucoside (AG), and afrormosin-7-O-glucoside-6{double prime}-O-malonate (AGM) were isolated and characterized from cell suspension cultures of alfalfa (Medicago sativa L.), where they were the major constitutive secondary metabolites. They were also found in alfalfa roots but not in other parts of the plant. The phytoalexin medicarpin accumulated rapidly in suspension cultured cells treated with elicitor from Colletotrichum lindemuthianum, and this was subsequently accompanied by an increase in the levels of MGM. In contrast, net accumulation of afrormosin conjugates was not affected by elicitor treatment. Labeling studies with ({sup 14}C)phenylalanine indicated that afrormosin conjugates were the major de novo synthesized isoflavonoid products in unelicited cells. During elicitation, ({sup 14}C)phenylalanine was incorporated predominantly into medicarpin, although a significant proportion of the newly synthesized medicarpin was also conjugated. Treatment of {sup 14}C-labeled, elicited cells with L-{alpha}-aminooxy-{beta}-phenylpropionic acid, a potent inhibitor of PAL activity in vivo, resulted in the initial appearance of labeled medicarpin of very low specific activity, suggesting that the phytoalexin could be released from a preformed conjugate under these conditions. Our data draw attention to the involvement of isoflavone hydroxylases during the constitutive and elicitor-induced accumulation of isoflavonoids and their conjugates in alfalfa cell cultures.

  20. Transgene silencing of sucrose synthase in alfalfa stem vascular tissue by a truncated phosphoenolpyruvate carboxylase: sucrose synthase construct

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An important role of sucrose synthase (SUS, EC 2.4.1.13) in plants is to provide UDP-glucose needed for cellulose synthesis in cell walls. We examined if over-expressing SUS in alfalfa (Medicago sativa L.) would increase cellulose content of stem cell walls. Alfalfa plants were transformed with two ...

  1. Aluminium-induced reduction of plant growth in alfalfa (Medicago sativa) is mediated by interrupting auxin transport and accumulation in roots.

    PubMed

    Wang, Shengyin; Ren, Xiaoyan; Huang, Bingru; Wang, Ge; Zhou, Peng; An, Yuan

    2016-01-01

    The objective of this study was to investigate Al(3+)-induced IAA transport, distribution, and the relation of these two processes to Al(3+)-inhibition of root growth in alfalfa. Alfalfa seedlings with or without apical buds were exposed to 0 or 100 μM AlCl3 and were foliar sprayed with water or 6 mg L(-1) IAA. Aluminium stress resulted in disordered arrangement of cells, deformed cell shapes, altered cell structure, and a shorter length of the meristematic zone in root tips. Aluminium stress significantly decreased the IAA concentration in apical buds and root tips. The distribution of IAA fluorescence signals in root tips was disturbed, and the IAA transportation from shoot base to root tip was inhibited. The highest intensity of fluorescence signals was detected in the apical meristematic zone. Exogenous application of IAA markedly alleviated the Al(3+)-induced inhibition of root growth by increasing IAA accumulation and recovering the damaged cell structure in root tips. In addition, Al(3+) stress up-regulated expression of AUX1 and PIN2 genes. These results indicate that Al(3+)-induced reduction of root growth could be associated with the inhibitions of IAA synthesis in apical buds and IAA transportation in roots, as well as the imbalance of IAA distribution in root tips. PMID:27435109

  2. Aluminium-induced reduction of plant growth in alfalfa (Medicago sativa) is mediated by interrupting auxin transport and accumulation in roots

    PubMed Central

    Wang, Shengyin; Ren, Xiaoyan; Huang, Bingru; Wang, Ge; Zhou, Peng; An, Yuan

    2016-01-01

    The objective of this study was to investigate Al3+-induced IAA transport, distribution, and the relation of these two processes to Al3+-inhibition of root growth in alfalfa. Alfalfa seedlings with or without apical buds were exposed to 0 or 100 μM AlCl3 and were foliar sprayed with water or 6 mg L−1 IAA. Aluminium stress resulted in disordered arrangement of cells, deformed cell shapes, altered cell structure, and a shorter length of the meristematic zone in root tips. Aluminium stress significantly decreased the IAA concentration in apical buds and root tips. The distribution of IAA fluorescence signals in root tips was disturbed, and the IAA transportation from shoot base to root tip was inhibited. The highest intensity of fluorescence signals was detected in the apical meristematic zone. Exogenous application of IAA markedly alleviated the Al3+-induced inhibition of root growth by increasing IAA accumulation and recovering the damaged cell structure in root tips. In addition, Al3+ stress up-regulated expression of AUX1 and PIN2 genes. These results indicate that Al3+-induced reduction of root growth could be associated with the inhibitions of IAA synthesis in apical buds and IAA transportation in roots, as well as the imbalance of IAA distribution in root tips. PMID:27435109

  3. Biological and Molecular Variability of Alfalfa mosaic virus Affecting Alfalfa Crop in Riyadh Region.

    PubMed

    Al-Saleh, Mohammed A; Amer, Mahmoud A

    2013-12-01

    In 2011-2012, sixty nine samples were collected from alfalfa plants showing viral infection symptoms in Riyadh region. Mechanical inoculation with sap prepared from two collected samples out of twenty five possitive for Alfalfa mosaic virus (AMV) by ELISA were produced systemic mosaic on Vigna unguiculata and Nicotiana tabacum, local lesion on Chenopodium amaranticolor and C. quinoa. Vicia faba indicator plants that induce mosaic and mottle with AMV-Sagir isolate and no infection with AMV-Wadi aldawasser isolate. Approximately 700-bp was formed by RT-PCR using AMV coat protein specific primer. Samples from infected alfalfa gave positive results, while healthy plant gave negative result using dot blot hybridization assay. The nucleotide sequences of the Saudi isolates were compared with corresponding viral nucleotide sequences reported in GenBank. The obtained results showed that the AMV from Australia, Brazil, Puglia and China had the highest similarity with AMV-Sajer isolate. While, the AMV from Spain and New Zealaland had the lowest similarity with AMV-Sajer and Wadi aldawasser isolates. The data obtained in this study has been deposited in the GenBank under the accession numbers KC434083 and KC434084 for AMV-Sajer and AMV- Wadialdawasser respectively. This is the first report regarding the gnetic make up of AMV in Saudi Arabia. PMID:25288969

  4. Changes of mesophyll and the rubisco activity in pea plants grown in clinostat

    NASA Astrophysics Data System (ADS)

    Adamchuk, N. I.

    In earlier research, it was found that microgravity causes alteration of mesophyll cell parameters and dislication at the ultrastructural level (Kordyum et al., 1989, Nedukha et al., 1991, Kordyum, 1997, Adamchuk et al., 2002). Also, destruction of the fine structure of chloroplasts was reported by Abilov et al. (1986), Aliev et al. (1987), Kordyum et al. (1989), and Adamchuk et al. (1999). In addition, Abilov et al. (1986), Aliev et al. (1987), Brown et al. (1993) have discovered the decrease in starch volume. The objective of this work was to compare quantitative ultrastructural parameters of mesophyll cells (including properties of their chloroplasts) and the level of Rubisco activity detected in clinorotated and control plants of pea (Pisum sativum L.). Plants were grown for 12 days in the nutritional medium of Hogland on a clinostat (with 2 rev. min-1 speed of rotation) at a temperature of 23-25°C and illumination 230 μ mol per m-2s-1. The comparison of transversal cross-sections of leaves has revealed a significant increase of mesophyll cell volume and intercellular space under experimental conditions. This expansion of mesophyll cells has correlated with an increase of the number of chloroplasts. Essential ultrastructural changes have affected the total volume of thylakoids. Also, the value of the photosynthetic membranes development in the clinorotated plants was higher 17.11 ± 1.94 μ m3 then in control -- 12.65 ± 1.83 μ m3 due to extension of destacking thylakoids. Increase of the volume density of plastoglobuli in the clinorotated plants on the 1.63-fold suggested the effect of either greater accumulation of lipid or acceleration of chloroplasts senescence. Under influence of clinorotation, the partial volume of starch inclusions significantly decreased in the spongy mesophyll chloroplasts -- 10.46 ± 1.80 % to compare with control -- 31.34 ± 2.37 %. However, the clinorotation of plants resulted in an increase of the Rubisco activity. Intensities

  5. First systematic evaluation of the potency of Cannabis sativa plants grown in Albania.

    PubMed

    Bruci, Zana; Papoutsis, Ioannis; Athanaselis, Sotirios; Nikolaou, Panagiota; Pazari, Ermira; Spiliopoulou, Chara; Vyshka, Gentian

    2012-10-10

    Cannabis products (marijuana, hashish, cannabis oil) are the most frequently abused illegal substances worldwide. Delta-9-tetrahydrocannabinol (THC) is the main psychoactive component of Cannabis sativa plant, whereas cannabidiol (CBD) and cannabinol (CBN) are other major but no psychoactive constituents. Many studies have already been carried out on these compounds and chemical research was encouraged due to the legal implications concerning the misuse of marijuana. The aim of this study was to determine THC, CBD and CBN in a significant number of cannabis samples of Albanian origin, where cannabis is the most frequently used drug of abuse, in order to evaluate and classify them according to their cannabinoid composition. A GC-MS method was used, in order to assay cannabinoid content of hemp samples harvested at different maturation degree levels during the summer months and grown in different areas of Albania. This method can also be used for the determination of plant phenotype, the evaluation of psychoactive potency and the control of material quality. The highest cannabinoid concentrations were found in the flowers of cannabis. The THC concentrations in different locations of Albania ranged from 1.07 to 12.13%. The influence of environmental conditions on cannabinoid content is discussed. The cannabinoid content of cannabis plants were used for their profiling, and it was used for their classification, according to their geographical origin. The determined concentrations justify the fact that Albania is an area where cannabis is extensively cultivated for illegal purposes. PMID:22608266

  6. Preference of the green peach aphid, Myzus persicae, for plants grown in sewage sludges

    SciTech Connect

    Culliney, T.W.; Pimentel, D.

    1987-08-01

    Since passage of the Clean Water Act in the 1970s, disposal of the millions of tonnes of sewage sludge generated annually has become a major concern of municipalities throughout the United States. With the range of other disposal options having narrowed in recent years, application of sludge to land is increasingly viewed as a practical and economical means to recycle this waste material. However, sludges from large cities with industries may be contaminated with various toxic chemicals, including polychlorinated biphenyls (PCBs), other organic chemicals, such as pesticides, and heavy metals. Sludge application to land thus has the potential adversely to affect biota and the functioning of terrestrial ecosystems. The authors previously demonstrated marked reductions in fecundity and survival of green peach aphids, Myzus persicae, on collard plants, Brassica oleracea var. sabellica, growing in soil treated with chemically contaminated sludge as compared to aphids on plants growing either in soil treated with uncontaminated sludge of soil conventionally fertilized. Reduced plant growth and increased restlessness in aphids in the contaminated sludge treatment were also observed. The purpose of the present study was to examine more closely the influence of sludge contaminants on aphid settling behavior as indicated by differential preference of M. persicae for leaves of its collard host grown under different soil conditions.

  7. Effects of ammonium on elemental nutrition of red spruce and indicator plants grown in acid soil

    SciTech Connect

    Hoelldampf, B.; Barker, A.V. )

    1993-01-01

    Decline of high elevation red spruce forests in the northeastern United States has been related to acid rain, particularly with respect to the deposition of nitrogenous materials. Ca and Mg deficiencies may be induced by input of air-borne nitrogenous nutrients into the forest ecosystem. This research investigated the effects of N nutrition on mineral nutrition of red spruce and radish, as an indicator plant, grown in acid forest soil. Red spruce and radishes in the greenhouse were treated with complete nutrient solutions with 15 mM N supplied as 0, 3.75, 7.5, 11.25, or 15 mM NH[sub 4][sup +] with the remainder being supplied as NO[sub 3][sup [minus

  8. Accumulation of mercury in selected plant species grown in soils contaminated with different mercury compounds

    SciTech Connect

    Su, Yi; Han, Fengxiang; Shiyab, Safwan; Chen, Jian; Monts, David L.

    2007-07-01

    , such as Indian mustard (Brassica juncea), a well-studied metal accumulator, exhibited severe chlorosis symptoms during some experiments. Among all the plant species studied, Chinese brake fern (Pteris vittata) accumulated significant amount of mercury in both roots and shoots and hence may be considered as a potential candidate for mercury phyto-extraction. During one experiment, Chinese brake ferns accumulated 540 mg/kg and 1469 mg/kg in shoots after 18 days of growing in soils treated with 500 parts-per-million (ppm) and 1000 ppm HgCl{sub 2} powder, respectively; no visual stress symptoms were observed. We also studied mercury phyto-remediation using aged soils that contained HgS, HgCl{sub 2}, or Hg(NO{sub 3}){sub 2}. We have found that up to hundreds of ppm mercury can be accumulated in the roots of Indian mustard plants grown with soil contaminated by mercury sulfide; HgS is assumed to be the most stable and also the predominant mercury form in flood plain soils. We have also started to investigate different mercury uptake mechanisms, such as root uptake of soil contaminant and foliar mercury accumulation from ambient air. We have observed mercury translocation from roots to shoot for Chinese fern and two Indian mustard varieties. (authors)

  9. Effects of different carbohydrate sources on fructan metabolism in plants of Chrysolaena obovata grown in vitro

    PubMed Central

    Trevisan, Flavio; Oliveira, Vanessa F.; Carvalho, Maria A. M.; Gaspar, Marília

    2015-01-01

    Chrysolaena obovata (Less.) Dematt., previously named Vernonia herbacea, is an Asteraceae native to the Cerrado which accumulates about 80% of the rhizophore dry mass as inulin-type fructans. Considering its high inulin production and the wide application of fructans, a protocol for C. obovata in vitro culture was recently established. Carbohydrates are essential for in vitro growth and development of plants and can also act as signaling molecules involved in cellular adjustments and metabolic regulation. This work aimed to evaluate the effect of different sources of carbohydrate on fructan metabolism in plants grown in vitro. For this purpose, C. obovata plants cultivated in vitro were submitted to carbon deprivation and transferred to MS medium supplemented with sucrose, glucose or fructose. Following, their fructan composition and activity and expression of genes encoding enzymes for fructan synthesis (1-SST and 1-FFT) and degradation (1-FEH) were evaluated. For qRT-PCR analysis partial cDNA sequences corresponding to two different C. obovata genes, 1-SST and 1-FFT, were isolated. As expected, C. obovata sequences showed highest sequence identity to other Asteraceae 1-SST and 1-FFT, than to Poaceae related proteins. A carbon deficit treatment stimulated the transcription of the gene 1-FEH and inhibited 1-SST and 1-FFT and carbohydrate supplementation promoted reversal of the expression profile of these genes. With the exception of 1-FFT, a positive correlation between enzyme activity and gene expression was observed. The overall results indicate that sucrose, fructose and glucose act similarly on fructan metabolism and that 1-FEH and 1-SST are transcriptionally regulated by sugar in this species. Cultivation of plants in increasing sucrose concentrations stimulated synthesis and inhibited fructan mobilization, and induced a distinct pattern of enzyme activity for 1-SST and 1-FFT, indicating the existence of a mechanism for differential regulation between them

  10. Wet fractionation for improved utilization of alfalfa leaves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Utilization of alfalfa could be greatly improved if protein-rich leaves were efficiently separated and preserved from fibrous stems. This work envisions a new harvest scheme combining three processes: mechanical leaf separation, dewatering, and fermentation. Gross plant fractionation is accomplished...

  11. Morphological and Molecular Variation in Perennial Medicago (Alfalfa) Germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L.) is one of the most important cultivated forage legumes worldwide. Understanding the areas of adaptation and genetic variation available in a crop species facilitates efforts to identify suitable germplasm for integration in plant breeding programs. Accessions that repr...

  12. Diversity of field isolates of sinorhizobium meliloti nodulating alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most alfalfa seed is treated with a rhizobial inoculant consisting of one or more strains of Sinorhizobium meliloti before planting to enhance nodulation of seedlings. However, little is known about the persistence of inoculated strains later in the season. There is also a paucity of information on ...

  13. Characterization of alfalfa populations contrasting for root system architecture (RSA)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The root system architecture affects the capacity for nutrient and water uptake thus impacting biomass yield production and may contribute to the persistence of perennial plants. The objectives of this study were to phenotype the roots of three alfalfa populations and identify differences between di...

  14. Aspartate Aminotransferase in Alfalfa Root Nodules : III. Genotypic and Tissue Expression of Aspartate Aminotransferase in Alfalfa and Other Species.

    PubMed

    Farnham, M W; Griffith, S M; Miller, S S; Vance, C P

    1990-12-01

    Aspartate aminotransferase (AAT) plays an important role in nitrogen metabolism in all plants and is particularly important in the assimilation of fixed N derived from the legume-Rhizoblum symbiosis. Two isozymes of AAT (AAT-1 and AAT-2) occur in alfalfa (Medicago sativa L.). Antibodies against alfalfa nodule AAT-2 do not recognize AAT-1, and these antibodies were used to study AAT-2 expression in different tissues and genotypes of alfalfa and also in other legume and nonlegume species. Rocket immunoelectrophoresis indicated that nodules of 38-day-old alfalfa plants contained about eight times more AAT-2 than did nodules of 7-day-old plants, confirming the nodule-enhanced nature of this isozyme. AAT-2 was estimated to make up 16, 15, 5, and 8 milligrams per gram of total soluble protein in mature nodules, roots, stems, and leaves, respectively, of effective N(2)-fixing alfalfa. The concentration of AAT-2 in nodules of ineffective non-N(2)-fixing alafalfa genotypes was about 70% less than that of effective nodules. Western blots of soluble protein from nodules of nine legume species indicated that a 40-kilodalton polypeptide that reacts strongly with AAT-2 antibodies is conserved in legumes. Nodule AAT-2 immunoprecipitation data suggested that amide- and ureide-type legumes may differ in expression and regulation of the enzyme. In addition, Western blotting and immunoprecipitations of AAT activity demonstrated that antibodies against alfalfa AAT-2 are highly cross-reactive with AAT enzyme protein in leaves of soybean (Glycine max L.), wheat (Triticum aestivum L.), and maize (Zea mays L.) and in roots of maize, but not with AAT in soybean and wheat roots. Results from this study indicate that AAT-2 is structurally conserved and localized in similar tissues among diverse species. PMID:16667896

  15. The Mouthparts Enriched Odorant Binding Protein 11 of the Alfalfa Plant Bug Adelphocoris lineolatus Displays a Preferential Binding Behavior to Host Plant Secondary Metabolites

    PubMed Central

    Sun, Liang; Wei, Yu; Zhang, Dan-Dan; Ma, Xiao-Yu; Xiao, Yong; Zhang, Ya-Nan; Yang, Xian-Ming; Xiao, Qiang; Guo, Yu-Yuan; Zhang, Yong-Jun

    2016-01-01

    Odorant binding proteins (OBPs) are proposed to be directly required for odorant discrimination and represent potential interesting targets for pest control. In the notoriously agricultural pest Adelphocoris lineolatus, our previous functional investigation of highly expressed antennal OBPs clearly supported this viewpoint, whereas the findings of the current study by characterizing of AlinOBP11 rather indicated that OBP in hemipterous plant bugs might fulfill a different and tantalizing physiological role. The phylogenetic analysis uncovered that AlinOBP11 together with several homologous bug OBP proteins are potential orthologs, implying they could exhibit a conserved function. Next, the results of expression profiles solidly showed that AlinOBP11 was predominantly expressed at adult mouthparts, the most important gustatory organ of Hemiptera mirid bug. Finally, a rigorously selective binding profile was observed in the fluorescence competitive binding assay, in which recombinant AlinOBP11 displayed much stronger binding abilities to non-volatile secondary metabolite compounds than the volatile odorants. These results reflect that AlinOBP11, even its orthologous proteins across bug species, could be associated with a distinctively conserved physiological role such as a crucial carrier for non-volatiles host secondary metabolites in gustatory system. PMID:27313540

  16. The Mouthparts Enriched Odorant Binding Protein 11 of the Alfalfa Plant Bug Adelphocoris lineolatus Displays a Preferential Binding Behavior to Host Plant Secondary Metabolites.

    PubMed

    Sun, Liang; Wei, Yu; Zhang, Dan-Dan; Ma, Xiao-Yu; Xiao, Yong; Zhang, Ya-Nan; Yang, Xian-Ming; Xiao, Qiang; Guo, Yu-Yuan; Zhang, Yong-Jun

    2016-01-01

    Odorant binding proteins (OBPs) are proposed to be directly required for odorant discrimination and represent potential interesting targets for pest control. In the notoriously agricultural pest Adelphocoris lineolatus, our previous functional investigation of highly expressed antennal OBPs clearly supported this viewpoint, whereas the findings of the current study by characterizing of AlinOBP11 rather indicated that OBP in hemipterous plant bugs might fulfill a different and tantalizing physiological role. The phylogenetic analysis uncovered that AlinOBP11 together with several homologous bug OBP proteins are potential orthologs, implying they could exhibit a conserved function. Next, the results of expression profiles solidly showed that AlinOBP11 was predominantly expressed at adult mouthparts, the most important gustatory organ of Hemiptera mirid bug. Finally, a rigorously selective binding profile was observed in the fluorescence competitive binding assay, in which recombinant AlinOBP11 displayed much stronger binding abilities to non-volatile secondary metabolite compounds than the volatile odorants. These results reflect that AlinOBP11, even its orthologous proteins across bug species, could be associated with a distinctively conserved physiological role such as a crucial carrier for non-volatiles host secondary metabolites in gustatory system. PMID:27313540

  17. Amelioration of Ozone-Induced Oxidative Damage in Wheat Plants Grown under High Carbon Dioxide (Role of Antioxidant Enzymes).

    PubMed Central

    Rao, M. V.; Hale, B. A.; Ormrod, D. P.

    1995-01-01

    O3-induced changes in growth, oxidative damage to protein, and specific activities of certain antioxidant enzymes were investigated in wheat plants (Triticum aestivum L. cv Roblin) grown under ambient or high CO2. High CO2 enhanced shoot biomass of wheat plants, whereas O3 exposure decreased shoot biomass. The shoot biomass was relatively unaffected in plants grown under a combination of high CO2 and O3. O3 exposure under ambient CO2 decreased photosynthetic pigments, soluble proteins, and ribulose-1,5-bisphosphate carboxylase/oxygenase protein and enhanced oxidative damage to proteins, but these effects were not observed in plants exposed to O3 under high CO2. O3 exposure initially enhanced the specific activities of superoxide dismutase, peroxidase, glutathione reductase, and ascorbate peroxidase irrespective of growth in ambient or high CO2. However, the specific activities decreased in plants with prolonged exposure to O3 under ambient CO2 but not in plants exposed to O3 under high CO2. Native gels revealed preferential changes in the isoform composition of superoxide dismutase, peroxidases, and ascorbate peroxidase of plants grown under a combination of high CO2 and O3. Furthermore, growth under high CO2 and O3 led to the synthesis of one new isoform of glutathione reductase. This could explain why plants grown under a combination of high CO2 and O3 are capable of resisting O3-induced damage to growth and proteins compared to plants exposed to O3 under ambient CO2. PMID:12228603

  18. Feeding behaviour of juvenile snails ( Helix pomatia) to four plant species grown at elevated atmospheric CO 2

    NASA Astrophysics Data System (ADS)

    Ledergerber, S.; Leadley, P. W.; Stöcklin, J.; Baur, Bruno

    1998-02-01

    The feeding behaviour of juveniles of the land snail Helix pomatia was examined in model plant communities consisting of Trifolium repens, Hieracium pilosella, Bromus erectus and Prunella vulgaris that are common species in extensively managed calcareous grasslands in the Swiss Jura mountains. The plant communities were grown either at ambient (350 ppm) or elevated (600 ppm) CO 2 concentrations. Leaves of T. repens and P. vulgaris grown in elevated atmospheric CO 2 had a lower specific leaf area, and leaves of T. repens had lower percentage N on a dry weight basis than leaves grown under ambient CO 2 concentration. Snails fed on all four plant species, but showed a overwhelming preference for T. repens (percentages of total biomass consumed were 91.9% at 350 ppm and 97.6% at 600 ppm). The species-specific feeding intensity of juvenile H. pomatia did not differ between the two treatments. The total dry weight of T. repens consumed by the snails was marginally greater ( P = 0.06) at elevated CO 2, but there were no significant differences in leaf N or leaf area eaten. These findings are similar to numerous other studies showing that invertebrates increase their consumption of plant material to balance reductions in plant N concentrations at elevated CO 2. The leaf biomass, leaf area and amount of nitrogen consumed of the other three plant species did not differ significantly between the two CO 2 treatments. Helix pomatia that fed on plants grown at elevated CO 2 atmosphere showed a larger increase in relative wet weight than those that fed on plants from ambient CO 2 conditions. However, the weight gain of H. pomatia was poorly correlated with amount of plant tissue consumed, so we suggest that the effect of CO 2 on weight gain in H. pomatia was due to a change in the quality of T. repens leaves.

  19. Using RNA-Seq for gene identification, polymorphism detection and transcript profiling in two alfalfa genotypes with divergent cell wall composition in stems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa [Medicago sativa (L.) sativa], a widely-grown perennial forage, has potential for development as a cellulosic feedstock for ethanol production. Identifying key genes regulating lignin and cellulose biosynthesis in alfalfa would advance its development as a cellulosic feedstock. However, the ...

  20. Successful tree planting techniques for drastically disturbed lands: A case study of the propagation planting of container-grown oak and nut trees in Missouri

    SciTech Connect

    Miller, S.

    1998-12-31

    Successful tree seedling establishment on drastically disturbed lands is contingent on seven major variables: (1) selection of proper native species, (2) purchase of the best quality planting stock, (3) correct handling of planting stock, (4) correct planting techniques, (5) effective control of competing vegetation, (6) proper soil conditions and preparation, (7) weather. Exotic species should not be planted to avoid past mistakes such as kudzu, Japanese honeysuckle, sericea lespedeza and chestnut blight. A major concern of reclamation specialists and ecosystem restorationists is obtaining high-quality plant materials with the correct provenance. Ecosystem restorationists, reclamation specialists, park managers and private landowners can easily and cheaply propagate native oak or other hardwood species from local parent stock using Whitcomb bottomless containers. Proper seed collection, storage and preparation techniques as well as propagation methods are critical for seedling growth and development into quality air-pruned planting stock. Air-pruned seedlings of local provenance can be outplanted in the fall after one growing season with little transplanting shock while developing extensive root systems prior to soil freezing in winter. Establishment success of container-grown seedlings greatly exceeds that of spring-planted bare-root seedlings. Fall-planted, container-grown seedlings have a decided advantage since their roots continue to grow throughout the fall and much of the winter, enabling them to better withstand summer drought and weedy competitors. Container-grown seedlings also allow a five- to six-month planting season compared to bare-root seedlings` four to six weeks. Since propagation costs are minimal, planters who grow their own save money on the planting stock. Because the quality is higher, home-grown seedlings have greater establishment success, saving labor, time and money. With better survival rates, far fewer trees need be planted as compared

  1. Composition and physical properties of starch in microgravity-grown plants

    NASA Technical Reports Server (NTRS)

    Kuznetsov, O. A.; Brown, C. S.; Levine, H. G.; Piastuch, W. C.; Sanwo-Lewandowski, M. M.; Hasenstein, K. H.; Sager, J. C. (Principal Investigator)

    2001-01-01

    The effect of spaceflight on starch development in soybean (Glycine max L., BRIC-03) and potato (Solanum tuberosum, Astroculture-05) was compared with ground controls by biophysical and biochemical measurements. Starch grains from plants from both flights were on average 20-50% smaller in diameter than ground controls. The ratio delta X/delta rho (delta X --difference of magnetic susceptibilities, delta rho--difference of densities between starch and water) of starch grains was ca. 15% and 4% higher for space-grown soybean cotyledons and potato tubers, respectively, than in corresponding ground controls. Since the densities of particles were similar for all samples (1.36 to 1.38 g/cm3), the observed difference in delta X/delta rho was due to different magnetic susceptibilities and indicates modified composition of starch grains. In starch preparations from soybean cotyledons (BRIC-03) subjected to controlled enzymatic degradation with alpha-amylase for 24 hours, 77 +/- 6% of the starch from the flight cotyledons was degraded compared to 58 +/- 12% in ground controls. The amylose content in starch was also higher in space-grown tissues. The good correlation between the amylose content and delta X/delta rho suggests, that the magnetic susceptibility of starch grains is related to their amylose content. Since the seedlings from the BRIC-03 experiment showed elevated post-flight ethylene levels, material from another flight experiment (GENEX) which had normal levels of ethylene was examined and showed no difference to ground controls in size distribution, density, delta X/delta rho and amylose content. Therefore the role of ethylene appears to be more important for changes in starch metabolism than microgravity. c2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  2. Composition and physical properties of starch in microgravity-grown plants

    NASA Astrophysics Data System (ADS)

    Kuznetsov, O. A.; Brown, C. S.; Levine, H. G.; Piastuch, W. C.; Sanwo-Lewandowski, M. M.; Hasenstein, K. H.

    2001-01-01

    The effect of spaceflight on starch development in soybean ( Glycine max L., BRIC-03) and potato ( Solanum tuberosum, Astroculture-05) was compared with ground controls by biophysical and biochemical measurements. Starch grains from plants from both flights were on average 20-50% smaller in diameter than ground controls. The ratio Δκ/Δρ (Δκ - difference of magnetic susceptibilities, Δρ - difference of densities between starch and water) of starch grains was ca. 15% and 4% higher for space-grown soybean cotyledons and potato tubers, respectively, than in corresponding ground controls. Since the densities of particles were similar for all samples (1.36 to 1.38 g/cm 3), the observed difference in Δκ/Δρ was due to different magnetic susceptibilities and indicates modified composition of starch grains. In starch preparations from soybean cotyledons (BRIC-03) subjected to controlled enzymatic degradation with α-amylase for 24 hours, 77±6% of the starch from the flight cotyledons was degraded compared to 58±12% in ground controls. The amylose content in starch was also higher in space-grown tissues. The good correlation between the amylose content and Δκ/Δρ suggests, that the magnetic susceptibility of starch grains is related to their amylose content. Since the seedlings from the BRIC-03 experiment showed elevated post-flight ethylene levels, material from another flight experiment (GENEX) which had normal levels of ethylene was examined and showed no difference to ground controls in size distribution, density, Δκ/Δρ and amylose content. Therefore the role of ethylene appears to be more important for changes in starch metabolism than microgravity.

  3. Surface-Applied Insecticide Treatments for the Elimination of Larval Japanese Beetle (Coleoptera: Scarabaeidae) From Field-Grown Nursery Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Japanese beetle, Popillia japonica Newman, continues to be a quarantine issue for nurseries shipping plants from the eastern U.S. to states west of the Mississippi River. Currently, the only pre-harvest treatments approved for field-grown nurseries in the U.S. Domestic Japanese Beetle Harmoniza...

  4. Drench Treatments for Management of Larval Japanese Beetle (Coleoptera: Scarabaeidae) in Field-Grown Balled and Burlapped Nursery Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The study evaluated insecticide drenches applied to post-harvest field-grown nursery plants harvested as 60-cm diameter balled and burlapped (B&B) root balls for controlling third instar Japanese beetle, Popillia japonica Newman. Bifenthrin, chlorpyrifos, lambda-cyhalothrin, and thiamethoxam were d...

  5. Transcriptomic and metabolomic analysis of Yukon Thellungiella plants grown in cabinets and their natural habitat show phenotypic plasticity

    PubMed Central

    2012-01-01

    Background Thellungiella salsuginea is an important model plant due to its natural tolerance to abiotic stresses including salt, cold, and water deficits. Microarray and metabolite profiling have shown that Thellungiella undergoes stress-responsive changes in transcript and organic solute abundance when grown under controlled environmental conditions. However, few reports assess the capacity of plants to display stress-responsive traits in natural habitats where concurrent stresses are the norm. Results To determine whether stress-responsive changes observed in cabinet-grown plants are recapitulated in the field, we analyzed leaf transcript and metabolic profiles of Thellungiella growing in its native Yukon habitat during two years of contrasting meteorological conditions. We found 673 genes showing differential expression between field and unstressed, chamber-grown plants. There were comparatively few overlaps between genes expressed under field and cabinet treatment-specific conditions. Only 20 of 99 drought-responsive genes were expressed both in the field during a year of low precipitation and in plants subjected to drought treatments in cabinets. There was also a general pattern of lower abundance among metabolites found in field plants relative to control or stress-treated plants in growth cabinets. Nutrient availability may explain some of the observed differences. For example, proline accumulated to high levels in cold and salt-stressed cabinet-grown plants but proline content was, by comparison, negligible in plants at a saline Yukon field site. We show that proline accumulated in a stress-responsive manner in Thellungiella plants salinized in growth cabinets and in salt-stressed seedlings when nitrogen was provided at 1.0 mM. In seedlings grown on 0.1 mM nitrogen medium, the proline content was low while carbohydrates increased. The relatively higher content of sugar-like compounds in field plants and seedlings on low nitrogen media suggests that

  6. Calcium localization in lettuce leaves with and without tipburn: comparison of controlled-environment and field-grown plants

    NASA Technical Reports Server (NTRS)

    Barta, D. J.; Tibbitts, T. W.

    1991-01-01

    An electron microprobe was used to determine tissue concentrations of Ca across 20-mm-long leaves of 'Green Lakes' crisphead lettuce (Lactuca sativa L.) with and without tipburn injury. Concentrations within the fifth and 14th leaves, counted from the cotyledons, from plants grown under controlled-environment conditions were compared to concentrations within similar leaves obtained from plants grown under field conditions. Only the 14th leaf from plants grown under controlled-environment conditions developed tipburn. Injured areas on these leaves had Ca concentrations as low as 0.2 to 0.3 mg g-1 dry weight. Uninjured areas of tipburned leaves contained from 0.4 to 0.5 mg g-1 dry weight. Concentrations across the uninjured 14th leaf from field-grown plants averaged 1.0 mg g-1 dry weight. Amounts across the uninjured fifth leaves from both environments averaged 1.6 mg g-1 dry weight. In contrast, Mg concentrations were higher in injured leaves than in uninjured leaves and thus were negatively correlated with Ca concentrations. Magnesium concentrations averaged 4.7 mg g-1 dry weight in injured leaves compared with 3.4 mg g-1 dry weight in uninjured leaves from both environments. Magnesium concentrations were uniform across the leaf. Potassium concentrations were highest at the leaf apex and decreased toward the base and also decreased from the midrib to the margin. Potassium averaged 51 mg g-1 dry weight in injured and uninjured leaves from both environments. No significant differences in K concentration were present between injured and uninjured leaves. This study documented that deficient concentrations of Ca were present in areas of leaf tissue developing tipburn symptoms and that concentrations were significantly higher in similar areas of other leaves that had no symptoms. This study also documented that Ca concentrations were significantly lower in enclosed leaves that exhibited tipburn symptoms than in exposed leaves that did not exhibit tipburn. Also, the

  7. Bioaccumulation of triclosan and triclocarban in plants grown in soils amended with municipal dewatered biosolids.

    PubMed

    Prosser, Ryan S; Lissemore, Linda; Topp, Edward; Sibley, Paul K

    2014-05-01

    Biosolids generally contain the microbiocidal agents triclosan (TCS) and triclocarban (TCC) that are persistent during wastewater treatment and sorp to organic material. The present study investigated the concentration of TCS in tissues of radish, carrot, and soybean grown in potted soil amended with biosolids. Highest mean concentrations of TCS in radish, carrot, and soybean root tissue midway through the life cycle were 24.8 ng/g, 49.8 ng/g, and 48.1 ng/g dry weight, respectively; by the conclusion of the test, however, concentrations had declined to 2.1 ng/g, 5.5 ng/g, and 8.4 ng/g dry weight, respectively. Highest mean concentrations of TCS in radish and carrot shoot tissue were 33.7 and 18.3 ng/g dry weight at days 19 and 45, respectively, but had declined to 13.7 ng/g and 5.5 ng/g dry weight at days 34 and 69, respectively. Concentration of TCS in all samples of soybean seeds was below method detection limit (i.e., 2.8 ng/g dry wt). The present study also examined the concentration of TCS and TCC in edible portions of green pepper, carrot, cucumber, tomato, radish, and lettuce plants grown in a field amended with biosolids. Triclosan was detected only in cucumber and radish up to 5.2 ng/g dry weight. Triclocarban was detected in carrot, green pepper, tomato, and cucumber up to 5.7 ng/g dry weight. On the basis of the present study and other studies, we estimate that vegetable consumption represents less than 0.5% of the acceptable daily intake of TCS and TCC. These results demonstrate that, if best management practices for land application of biosolids in Ontario are followed, the concentration of TCS and TCC in edible portions of plants represents a negligible exposure pathway to humans. PMID:24375516

  8. Variation in alfalfa leafcutting bee (hymenoptera: megachilidae) reproductive success according to location of nests in United States commercial domiciles.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low, medium, and high stocking densities of Megachile rotundata, the alfalfa leafcutting bee, were released over four years in three research plots of Utah alfalfa planted at seed-production rates. A low number of bees (46-79% of released) survived the incubation and field emergence processes, and ...

  9. Modelling the Dynamics of Feral Alfalfa Populations and Its Management Implications

    PubMed Central

    Bagavathiannan, Muthukumar V.; Begg, Graham S.; Gulden, Robert H.; Van Acker, Rene C.

    2012-01-01

    Background Feral populations of cultivated crops can pose challenges to novel trait confinement within agricultural landscapes. Simulation models can be helpful in investigating the underlying dynamics of feral populations and determining suitable management options. Methodology/Principal Findings We developed a stage-structured matrix population model for roadside feral alfalfa populations occurring in southern Manitoba, Canada. The model accounted for the existence of density-dependence and recruitment subsidy in feral populations. We used the model to investigate the long-term dynamics of feral alfalfa populations, and to evaluate the effectiveness of simulated management strategies such as herbicide application and mowing in controlling feral alfalfa. Results suggest that alfalfa populations occurring in roadside habitats can be persistent and less likely to go extinct under current roadverge management scenarios. Management attempts focused on controlling adult plants alone can be counterproductive due to the presence of density-dependent effects. Targeted herbicide application, which can achieve complete control of seedlings, rosettes and established plants, will be an effective strategy, but the seedbank population may contribute to new recruits. In regions where roadside mowing is regularly practiced, devising a timely mowing strategy (early- to mid-August for southern Manitoba), one that can totally prevent seed production, will be a feasible option for managing feral alfalfa populations. Conclusions/Significance Feral alfalfa populations can be persistent in roadside habitats. Timely mowing or regular targeted herbicide application will be effective in managing feral alfalfa populations and limit feral-population-mediated gene flow in alfalfa. However, in the context of novel trait confinement, the extent to which feral alfalfa populations need to be managed will be dictated by the tolerance levels established by specific production systems for specific

  10. Tetrasomic Segregation for Multiple Alleles in Alfalfa

    PubMed Central

    Quiros, Carlos F.

    1982-01-01

    Evidence of tetrasomic inheritance in alfalfa, Medicago sativa L. and M. falcata L., for multiple codominant alleles at three isozymic loci is reported in this study. The locus Prx-1 governing anodal peroxidase and the loci Lap-1 and Lap-2 governing anodal leucine-aminopeptidase were studied by starch gel electrophoresis in seedling root tissue or seeds. The progenies from several di-, tri- or tetra-allelic plants belong to the species M. sativa and M. falcata and their hybrids were studied for the segregation of the three genes. In all cases, tetrasomic inheritance of chromosomal-type segregation was observed. In another progeny resulting from the crossing of two plants involving four different alleles at locus Lap-2, tetrasomic segregation with the possible occurrence of double reduction was observed. This study presents direct evidence of autotetraploidy and the existence of tetra-allelic loci in alfalfa. It also supports the concept that the species M. sativa and M. falcata are genetically close enough to be considered biotypes of a common species. PMID:17246077

  11. Characterization of natural leaf senescence in tobacco (Nicotiana tabacum) plants grown in vitro.

    PubMed

    Uzelac, Branka; Janošević, Dušica; Simonović, Ana; Motyka, Václav; Dobrev, Petre I; Budimir, Snežana

    2016-03-01

    Leaf senescence is a highly regulated final phase of leaf development preceding massive cell death. It results in the coordinated degradation of macromolecules and the subsequent nutrient relocation to other plant parts. Very little is still known about early stages of leaf senescence during normal leaf ontogeny that is not triggered by stress factors. This paper comprises an integrated study of natural leaf senescence in tobacco plants grown in vitro, using molecular, structural, and physiological information. We determined the time sequence of ultrastructural changes in mesophyll cells during leaf senescence, showing that the degradation of chloroplast ultrastructure fully correlated with changes in chlorophyll content. The earliest degenerative changes in chloroplast ultrastructure coinciding with early chromatin condensation were observed already in mature green leaves. A continuum of degradative changes in chloroplast ultrastructure, chromatin condensation and aggregation, along with progressive decrease in cytoplasm organization and electron density were observed in the course of mesophyll cells ageing. Although the total amounts of endogenous cytokinins gradually increased during leaf ontogenesis, the proportion of bioactive cytokinin forms, as well as their phosphate precursors, in total cytokinin content rapidly declined with ageing. Endogenous indole-3-acetic acid (IAA) levels were strongly reduced in senescent leaves, and a decreasing tendency was also observed for abscisic acid (ABA) levels. Senescence-associated tobacco cysteine proteases (CP, E.C. 3.4.22) CP1 and CP23 genes were induced in the initial phase of senescence. Genes encoding glutamate dehydrogenase (GDH, E.C. 1.4.1.2) and one isoform of cytosolic glutamine synthetase (GS1, E.C. 6.3.1.2) were induced in the late stage of senescence, while chloroplastic GS (GS2) gene showed a continuous decrease with leaf ageing. PMID:25837009

  12. Heavy metal accumulation in wheat plant grown in soil amended with industrial sludge.

    PubMed

    Bose, Sutapa; Bhattacharyya, A K

    2008-01-01

    The concentrations of different forms of Zn, Cu, Mn, Ni, Cd, Cr, Pb and Fe metals were determined for the roadside sludge collected from pickling-rolling and electroplating industrial area. In sludge the relative abundance of total heavy metals were Fe>Mn>Cr>Ni>Cu>Pb>Zn>Cd and DTPA-extractable metals were in the order--Fe>Ni>Mn>Cr>Cu>Zn>Pb>Cd. Pot-culture experiment was conducted in soils amended with sludge (0%, 10%, 20%, 30%), pretreated with lime (0%, 0.5% and 1%). The soils were alkaline in nature (pH>8.3) with organic carbon contents were 0.34% and 0.72%. The most abundant total and bio-available metal was Fe. Two wheat seedlings were grown in each pot containing 3kg sludge-amended or control soil and the experiment was conducted till harvesting. Application of sludge increased both total and bio-available forms of metals in the soils, while lime application decreased the bioavailability of heavy metals in sludge-amended soils. The content of organic carbon showed positive correlation with all metals except Zn, Cr and Pb. CEC also showed a strong positive correlation (R2>0.7) with Fe, Mn, Cu, Ni and Cd. Though wheat plants are not accumulators, the translocation efficiency was appreciably high. The translocation factor from shoot to grain was found smaller than that of root to shoot of wheat plants. This makes an implication that the heavy metal accumulation was proportionally lesser in grain than in shoot. In, 10% sludge with 0.5% lime-amended soils; each of these toxic heavy metals was found to be within permissible range (USEPA). Hence, on the basis of present study, the best possible treatment may be recommended. PMID:17825356

  13. European corn borer (Lepidoptera: Crambidae) infestation level and plant growth stage on whole-plant corn yield grown for silage in Virginia.

    PubMed

    Tiwari, S; Youngman, R R; Laub, C A; Brewster, C C; Jordan, T A; Teutsch, C

    2009-12-01

    Field experiments were conducted in 2004 and 2005 to determine the effect of different levels of hand-infested third instar European corn borer, Ostrinia nubilalis (Hiibner) (Lepidoptera: Crambidae), on whole-plant yield and plant growth stage in corn, Zea mays L., grown for silage. In 2004 and 2005, European corn borer infestation level had a significant negative impact on whole-plant yield (grams of dry matter per plant) with increasing infestation; however, whole-plant yield was not significantly affected by plant growth stage in either year. In 2004, the six larvae per plant treatment caused the greatest percentage of reduction (23.4%) in mean (+/-SEM) whole-plant yield (258.5 +/- 21.0 g dry matter per plant) compared with the Bacillus thuringiensis (Bt) CrylAb control (337.3 +/- 11.1 g dry matter per plant). In 2005, the five larvae per plant treatment caused the greatest percentage of reduction (8.3%) in mean whole-plant yield (282.3 +/- 10.8 g dry matter per plant) compared with the Bt CrylAb control (307.8 +/- 8.3 g dry matter per plant). The relationship between mean whole-plant yield and European corn borer larvae infestation level from the pooled data of both years was described well by using an exponential decay model (r2 = 0.84, P = 0.0038). The economic injury level for silage corn was estimated to be approximately 73% higher than for corn grown for grain based on similar control costs and crop values. In addition, plant growth stage and European corn borer infestation level had no effect on percentage of acid detergent fiber, neutral detergent fiber, and crude protein values in either year of the study. PMID:20069843

  14. Genetic Mapping of Persistence in Tetraploid Alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Persistence is a critical trait for alfalfa, yet the genetics of this trait is poorly understood. Herein, we characterize an F1 alfalfa population derived from the cross between the two cultivated alfalfa subpecies for persistence in three production seasons at Ames and Nashua, Iowa locations and o...

  15. Managing the rotation from alfalfa to corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa provides many benefits to cropping systems. These benefits occur both during alfalfa production and during the subsequent crops that follow. Some of the common benefits during alfalfa production are increased soil organic matter, decreased soil erosion, and decreased soil nitrate leaching lo...

  16. Ensiling Characteristics of Alfalfa Leaves and Stems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The separate harvesting of alfalfa leaves and stems would provide farmers more flexibility in the harvesting and utilization of alfalfa, but a key issue is storage. In three trials, unwilted alfalfa leaves were ensiled alone or with cell wall degrading enzymes, formic acid or lactic acid bacterial i...

  17. Photomorphogenesis, photosynthesis, and seed yield of wheat plants grown under red light-emitting diodes (LEDs) with and without supplemental blue lighting

    NASA Technical Reports Server (NTRS)

    Goins, G. D.; Yorio, N. C.; Sanwo, M. M.; Brown, C. S.; Sager, J. C. (Principal Investigator)

    1997-01-01

    Red light-emitting diodes (LEDs) are a potential light source for growing plants in spaceflight systems because of their safety, small mass and volume, wavelength specificity, and longevity. Despite these attractive features, red LEDs must satisfy requirements for plant photosynthesis and photomorphogenesis for successful growth and seed yield. To determine the influence of gallium aluminium arsenide (GaAlAs) red LEDs on wheat photomorphogenesis, photosynthesis, and seed yield, wheat (Triticum aestivum L., cv. 'USU-Super Dwarf') plants were grown under red LEDs and compared to plants grown under daylight fluorescent (white) lamps and red LEDs supplemented with either 1% or 10% blue light from blue fluorescent (BF) lamps. Compared to white light-grown plants, wheat grown under red LEDs alone demonstrated less main culm development during vegetative growth through preanthesis, while showing a longer flag leaf at 40 DAP and greater main culm length at final harvest (70 DAP). As supplemental BF light was increased with red LEDs, shoot dry matter and net leaf photosynthesis rate increased. At final harvest, wheat grown under red LEDs alone displayed fewer subtillers and a lower seed yield compared to plants grown under white light. Wheat grown under red LEDs+10% BF light had comparable shoot dry matter accumulation and seed yield relative to wheat grown under white light. These results indicate that wheat can complete its life cycle under red LEDs alone, but larger plants and greater amounts of seed are produced in the presence of red LEDs supplemented with a quantity of blue light.

  18. Beneficial effects of silicon on hydroponically grown corn salad (Valerianella locusta (L.) Laterr) plants.

    PubMed

    Gottardi, Stefano; Iacuzzo, Francesco; Tomasi, Nicola; Cortella, Giovanni; Manzocco, Lara; Pinton, Roberto; Römheld, Volker; Mimmo, Tanja; Scampicchio, Matteo; Dalla Costa, Luisa; Cesco, Stefano

    2012-07-01

    Soil-less cultivation of horticultural crops represents a fairly recent innovation to traditional agriculture which has several advantages including higher water-use efficiency. When plants are grown with this system, their roots come in contact with nutrients solely via the hydroponic solution. Although its beneficial effects have been widely demonstrated, silicon (Si) is mostly omitted from the composition of nutrient solutions. Therefore, the objective of this study was to assess the beneficial effect of Si addition to hydroponic solution on quali-quantitative aspects of edible production of two cultivars of corn salad (Valerianella locusta (L.) Laterr.) grown in soil-less floating system. Impacts on shelf life of this food were also studied. Results show that the supply of Si increased the edible yield and the quality level reducing the nitrate concentration in edible tissues. This result might be attributed to changes either in the metabolism (such as the nitrate assimilation process) or to the functionality of root mechanisms involved in the nutrient acquisition from the outer medium. In fact, our results show for the first time the ability of Si to modulate the root activity of nitrate and Fe uptake through, at least in part, a regulation of gene expression levels of the proteins involved in this phenomenon. In addition, the presence of Si decreased the levels of polyphenoloxidase gene expression at harvest and, in post-harvest, slowed down the chlorophyll degradation delaying leaf senescence and thus prolonging the shelf life of these edible tissues. In conclusion, data showed that the addition of Si to the nutrient solution can be a useful tool for improving quali-quantitatively the yield of baby leaf vegetable corn salad as well as its shelf life. Since the amelioration due to the Si has been achieved only with one cultivar, the recommendation of its inclusion in the nutrient solution does not exclude the identification of cultivars suitable for this

  19. Iron-Superoxide Dismutase Expression in Transgenic Alfalfa Increases Winter Survival without a Detectable Increase in Photosynthetic Oxidative Stress Tolerance1

    PubMed Central

    McKersie, Bryan D.; Murnaghan, Julia; Jones, Kim S.; Bowley, Stephen R.

    2000-01-01

    To determine whether overexpression of Fe-superoxide (SOD) dismutase would increase superoxide-scavenging capacity and thereby improve the winter survival of transgenic alfalfa (Medicago sativa L.) plants, two genotypes were transformed with the vector pEXSOD10, which contains a cDNA for Arabidopsis Fe-SOD with a chloroplast transit peptide and cauliflower mosaic virus 35S promoter. A novel Fe-SOD was detected by native PAGE in both greenhouse- and field-grown transgenic plants, but activity varied among independent transgenic plants. The increased Fe-SOD activity was associated with increased winter survival over 2 years in field trials, but not with oxidative stress tolerance as measured by resistance of leaves to methyl viologen, a superoxide generator. Total shoot dry matter production over 2 harvest years was not associated with Fe-SOD activity. There was no detectable difference in the pattern of primary freezing injury, as shown by vital staining, nor was there additional accumulation of carbohydrates in field-acclimated roots of the transgenic alfalfa plants. We did not detect any difference in growth of one transgenic plant with high Fe-SOD activity compared with a non-transgenic control. Therefore, the improvement in winter survival did not appear to be a consequence of improved oxidative stress tolerance associated with photosynthesis, nor was it a consequence of a change in primary freezing injury. We suggest that Fe-SOD overexpression reduced secondary injury symptoms and thereby enhanced recovery from stresses experienced during winter. PMID:10759538

  20. Expression of β-Amylase from Alfalfa Taproots1

    PubMed Central

    Gana, Joyce A.; Kalengamaliro, Newton E.; Cunningham, Suzanne M.; Volenec, Jeffrey J.

    1998-01-01

    Alfalfa (Medicago sativa L.) roots contain large quantities of β-amylase, but little is known about its role in vivo. We studied this by isolating a β-amylase cDNA and by examining signals that affect its expression. The β-amylase cDNA encoded a 55.95-kD polypeptide with a deduced amino acid sequence showing high similarity to other plant β-amylases. Starch concentrations, β-amylase activities, and β-amylase mRNA levels were measured in roots of alfalfa after defoliation, in suspension-cultured cells incubated in sucrose-rich or -deprived media, and in roots of cold-acclimated germ plasms. Starch levels, β-amylase activities, and β-amylase transcripts were reduced significantly in roots of defoliated plants and in sucrose-deprived cell cultures. β-Amylase transcript was high in roots of intact plants but could not be detected 2 to 8 d after defoliation. β-Amylase transcript levels increased in roots between September and October and then declined 10-fold in November and December after shoots were killed by frost. Alfalfa roots contain greater β-amylase transcript levels compared with roots of sweetclover (Melilotus officinalis L.), red clover (Trifolium pratense L.), and birdsfoot trefoil (Lotus corniculatus L.). Southern analysis indicated that β-amylase is present as a multigene family in alfalfa. Our results show no clear association between β-amylase activity or transcript abundance and starch hydrolysis in alfalfa roots. The great abundance of β-amylase and its unexpected patterns of gene expression and protein accumulation support our current belief that this protein serves a storage function in roots of this perennial species. PMID:9847126

  1. Pathogenicity of Two Populations of Meloidogyne hapla Chitwood on Alfalfa and Sainfoin.

    PubMed

    Wofford, D S; Gray, F A; Eckert, J W

    1989-01-01

    The pathogenicity of two populations of the northern root-knot nematode, Meloidogyne hapla Chitwood, population 1 (P1) from alfalfa and population 2 (P2) from sainfoin, was studied on both alfalfa and sainfoin for 25 weeks. Alfalfa and sainfoin plants inoculated with P2 had significantly (P plants inoculated with P1. Plant stands over all weeks for the uninoculated control, P1, and P2 were 90.5, 78.5, and 64.0% for alfalfa and 84.5, 51.0, and 41.0% for sainfoin, respectively. The increased virulence of P2 was again shown when means of plant species were combined (inoculation x week of count interaction). Plants inoculated with P2 had significantly higher mortality than either those inoculated with P1 or the uninoculated control beginning at week 7 and continuing through week 25. Plant stands over species at 25 weeks for the uninoculated control, P1, and P2 were 82.5, 29.0, and 18.0%, respectively. Sainfoin was significantly more susceptible to either population than alfalfa (plant species x week of count interaction). Separation between species first occurred after week 7 and continued until week 25. Percentages of plants remaining for alfalfa and sainfoin were 61.5 and 25.0 after 25 weeks. Significantly higher reproduction occurred in the alfalfa plants remaining after 25 weeks in P2 than in P1. Mean number of eggs per root system were 60,371 for P1 and 104,438 for P2, a difference of 42%. The results of this study indicate a need for breeders to adequately sample nematode populations present in the intended area of cultivar use and to design screening procedures to account for population pathogenicity variability. PMID:19287580

  2. Uptake of heavy metals by vegetable plants grown on contaminated soil and their bioavailability in the human gastrointestinal tract.

    PubMed

    Intawongse, Marisa; Dean, John R

    2006-01-01

    Lettuce, spinach, radish and carrot were grown on compost that had previously been contaminated at different concentrations of Cd, Cu, Mn, Pb and Zn. Control plants of each vegetable were also grown on unadulterated compost. The experiment was carried out under greenhouse conditions. Mature plants were harvested and their roots and leaves collected. Soil samples from each growing pot and plant materials were acid digested and analysed to determine total metal concentration. Flame-Atomic Absorption Spectroscopy (FAAS) was employed to determine metal concentrations in soil and plant samples (Mn and Zn), while Cd, Cu and Pb in plant materials were analysed by Differential Pulse Anodic Stripping Voltammetry (DP-ASV). Soil (BCR 146R and GBW 07310) and plant (tea leaves, INCT-TL-1) certified reference materials were used to assess accuracy and precision. The edible part of plants, i.e. the leaves of lettuce and spinach and the roots of radish and carrot, were also extracted using an in vitro gastrointestinal (GI) extraction to assess metal bioavailability. The results showed that the uptake of Cd, Cu, Mn and Zn by plants corresponded to the increasing level of soil contamination, while the uptake of Pb was low. Soil-to-plant transfer factor (TF) values decreased from Mn > Zn > Cd > Cu > Pb. Moreover, it was observed from this investigation that individual plant types greatly differ in their metal uptake, e.g. spinach accumulated a high content of Mn and Zn, while relatively lower concentrations were found for Cu and Pb in their tissues. From the in vitro gastrointestinal (GI) study, results indicate that metal bioavailability varied widely from element to element and according to different plant types. The greatest extent of metal releasing was found in lettuce (Mn, 63.7%), radish (Cu, 62.5%), radish (Cd, 54.9%), radish (Mn, 45.8%) and in lettuce (Zn, 45.2%). PMID:16393813

  3. Growth and feeding response of Pseudoplusia includens (Lepidoptera:Noctuidae) to host plants grown in controlled carbon dioxide atmospheres

    SciTech Connect

    Lincoln, D.E.; Sionit, N.; Strain, B.R.

    1984-12-01

    Rising atmospheric carbon dioxide may alter plant/herbivore interactions. The projected rise in atmospheric carbon dioxide is expected to increase plant productivity, but little evidence is available regarding effects on insect feeding or growth. Leaves of soybean plants grown under three carbon dioxide regimes (350, 500, and 650 ..mu..l/liter) were fed to soybean looper larvae. Larvae fed at increasingly higher rates on plants from elevated carbon dioxide atmospheres: 80% greater rates on leaves from the 650 ..mu..l/liter treatment than on leaves from the 350 ..mu..l/litter treatment. Variation in larval feeding was related to the leaf content of nitrogen and water and to the leaf-specific weight, each of which was altered by the carbon dioxide growth regime of the soybean plants. This study suggests that the impact of herbivores may increase as the level of atmospheric carbon dioxide rises.

  4. Molecular analysis of genetic fidelity in Cannabis sativa L. plants grown from synthetic (encapsulated) seeds following in vitro storage.

    PubMed

    Lata, Hemant; Chandra, Suman; Techen, Natascha; Khan, Ikhlas A; ElSohly, Mahmoud A

    2011-12-01

    The increasing utilization of synthetic (encapsulated) seeds for germplasm conservation and propagation necessitates the assessment of genetic stability of conserved propagules following their plantlet conversion. We have assessed the genetic stability of synthetic seeds of Cannabis sativa L. during in vitro multiplication and storage for 6 months at different growth conditions using inter simple sequence repeat (ISSR) DNA fingerprinting. Molecular analysis of randomly selected plants from each batch was conducted using 14 ISSR markers. Of the 14 primers tested, nine produced 40 distinct and reproducible bands. All the ISSR profiles from in vitro stored plants were monomorphic and comparable to the mother plant which confirms the genetic stability among the clones. GC analysis of six major cannabinoids [Δ(9)-tetrahydrocannabinol, tetrahydrocannabivarin, cannabidiol, cannabichromene, cannabigerol and cannabinol] showed homogeneity in the re-grown clones and the mother plant with insignificant differences in cannabinoids content, thereby confirming the stability of plants derived from synthetic seeds following 6 months storage. PMID:21805186

  5. Effects of Temperature on the Pathogenicity of Tylenchorhynchus clarus to Alfalfa and Observations on Feeding

    PubMed Central

    Noel, Gregory R.; Lownsbery, B. F.

    1978-01-01

    The involvement of Tylenchorhynchus clarus in plant disease is reported. Addition of a suspension of surface-axenized nematodes reduced top and root growth of alfalfa. Reproduction of T. clarus was greater at 24 and 27 than at 21 C. The interaction of nematodes with temperature did not produce significant effects on alfalfa growth in the 4.5-mo experimental period. T. clarus fed endo- and ectoparasitically. PMID:19305838

  6. Role of Silicon Counteracting Cadmium Toxicity in Alfalfa (Medicago sativa L.).

    PubMed

    Kabir, Ahmad H; Hossain, Mohammad M; Khatun, Most A; Mandal, Abul; Haider, Syed A

    2016-01-01

    Cadmium (Cd) is one of the most phytotoxic elements causing an agricultural problem and human health hazards. This work investigates whether and how silicon (Si) ameliorates Cd toxicity in Alfalfa. The addition of Si in Cd-stressed plants caused significant improvement in morpho-physiological features as well as total protein and membrane stability, indicating that Si does have critical roles in Cd detoxification in Alfalfa. Furthermore, Si supplementation in Cd-stressed plants showed a significant decrease in Cd and Fe concentrations in both roots and shoots compared with Cd-stressed plants, revealing that Si-mediated tolerance to Cd stress is associated with Cd inhibition in Alfalfa. Results also showed no significant changes in the expression of two metal chelators [MsPCS1 (phytochelatin synthase) and MsMT2 (metallothionein)] and PC (phytochelatin) accumulation, indicating that there may be no metal sequestration or change in metal sequestration following Si application under Cd stress in Alfalfa. We further performed a targeted study on the effect of Si on Fe uptake mechanisms. We observed the consistent reduction in Fe reductase activity, expression of Fe-related genes [MsIRT1 (Fe transporter), MsNramp1 (metal transporter) and OsFRO1 (ferric chelate reductase] and Fe chelators (citrate and malate) by Si application to Cd stress in roots of Alfalfa. These results support that limiting Fe uptake through the down-regulation of Fe acquisition mechanisms confers Si-mediated alleviation of Cd toxicity in Alfalfa. Finally, an increase of catalase, ascorbate peroxidase, and superoxide dismutase activities along with elevated methionine and proline subjected to Si application might play roles, at least in part, to reduce H2O2 and to provide antioxidant defense against Cd stress in Alfalfa. The study shows evidence of the effect of Si on alleviating Cd toxicity in Alfalfa and can be further extended for phytoremediation of Cd toxicity in plants. PMID:27512401

  7. Role of Silicon Counteracting Cadmium Toxicity in Alfalfa (Medicago sativa L.)

    PubMed Central

    Kabir, Ahmad H.; Hossain, Mohammad M.; Khatun, Most A.; Mandal, Abul; Haider, Syed A.

    2016-01-01

    Cadmium (Cd) is one of the most phytotoxic elements causing an agricultural problem and human health hazards. This work investigates whether and how silicon (Si) ameliorates Cd toxicity in Alfalfa. The addition of Si in Cd-stressed plants caused significant improvement in morpho-physiological features as well as total protein and membrane stability, indicating that Si does have critical roles in Cd detoxification in Alfalfa. Furthermore, Si supplementation in Cd-stressed plants showed a significant decrease in Cd and Fe concentrations in both roots and shoots compared with Cd-stressed plants, revealing that Si-mediated tolerance to Cd stress is associated with Cd inhibition in Alfalfa. Results also showed no significant changes in the expression of two metal chelators [MsPCS1 (phytochelatin synthase) and MsMT2 (metallothionein)] and PC (phytochelatin) accumulation, indicating that there may be no metal sequestration or change in metal sequestration following Si application under Cd stress in Alfalfa. We further performed a targeted study on the effect of Si on Fe uptake mechanisms. We observed the consistent reduction in Fe reductase activity, expression of Fe-related genes [MsIRT1 (Fe transporter), MsNramp1 (metal transporter) and OsFRO1 (ferric chelate reductase] and Fe chelators (citrate and malate) by Si application to Cd stress in roots of Alfalfa. These results support that limiting Fe uptake through the down-regulation of Fe acquisition mechanisms confers Si-mediated alleviation of Cd toxicity in Alfalfa. Finally, an increase of catalase, ascorbate peroxidase, and superoxide dismutase activities along with elevated methionine and proline subjected to Si application might play roles, at least in part, to reduce H2O2 and to provide antioxidant defense against Cd stress in Alfalfa. The study shows evidence of the effect of Si on alleviating Cd toxicity in Alfalfa and can be further extended for phytoremediation of Cd toxicity in plants. PMID:27512401

  8. Genome-wide expression analysis of reactive oxygen species gene network in Mizuna plants grown in long-term spaceflight

    PubMed Central

    2014-01-01

    Background Spaceflight environment have been shown to generate reactive oxygen species (ROS) and induce oxidative stress in plants, but little is known about the gene expression of the ROS gene network in plants grown in long-term spaceflight. The molecular response and adaptation to the spaceflight environment of Mizuna plants harvested after 27 days of cultivation onboard the International Space Station (ISS) were measured using genome-wide mRNA expression analysis (mRNA-Seq). Results Total reads of transcripts from the Mizuna grown in the ISS as well as on the ground by mRNA-Seq showed 8,258 and 14,170 transcripts up-regulated and down-regulated, respectively, in the space-grown Mizuna when compared with those from the ground-grown Mizuna. A total of 20 in 32 ROS oxidative marker genes were up-regulated, including high expression of four hallmarks, and preferentially expressed genes associated with ROS-scavenging including thioredoxin, glutaredoxin, and alternative oxidase genes. In the transcription factors of the ROS gene network, MEKK1-MKK4-MPK3, OXI1-MKK4-MPK3, and OXI1-MPK3 of MAP cascades, induction of WRKY22 by MEKK1-MKK4-MPK3 cascade, induction of WRKY25 and repression of Zat7 by Zat12 were suggested. RbohD and RbohF genes were up-regulated preferentially in NADPH oxidase genes, which produce ROS. Conclusions This large-scale transcriptome analysis revealed that the spaceflight environment induced oxidative stress and the ROS gene network activation in the space-grown Mizuna. Among transcripts altered in expression by space conditions, some were common genes response to abiotic and biotic stress. Furthermore, certain genes were exclusively up-regulated in Mizuna grown on the ISS. Surprisingly, Mizuna grew in space normally, as well as on the ground, demonstrating that plants can acclimate to long-term exposure in the spaceflight environment by reprogramming the expression of the ROS gene network. PMID:24393219

  9. Analysis of genetic relationships among Rosa damascena plants grown in Turkey by using AFLP and microsatellite markers.

    PubMed

    Baydar, Nilgün Göktürk; Baydar, Hasan; Debener, Thomas

    2004-08-01

    Rosa damascena Mill. is the most important rose species for rose oil production. The main rose oil producers in the world are Turkey and Bulgaria and they obtain the rose oil almost exclusively from R. damascena. In spite of coming from the same original populations, R. damascena plants grown in Turkey show some morphological differences. In this study, it was aimed to investigate the genetic relationships among R. damascena plants grown in Turkey by using microsatellite and AFLP markers. Twenty three AFLP and nine microsatellite primer pairs were used for this aim. No polymorphism could be detected among the plants, as the marker patterns obtained from different plants are identical. The conclusion from these data is that all R. damascena plants under study are derived from the same original genotype by vegetative propagation. Furthermore, the observed morphological differences originate from point mutations not detectable by molecular markers. Therefore, they are equivalent to sport mutations frequently observed in cut and garden rose varieties. PMID:15246662

  10. Isolation of RNA from field-grown jute (Corchorus capsularis) plant in different developmental stages for effective downstream molecular analysis.

    PubMed

    Samanta, Pradipta; Sadhukhan, Sanjoy; Das, Subrata; Joshi, Alpana; Sen, Soumitra K; Basu, Asitava

    2011-10-01

    Jute (Corchorus capsularis), as a natural fibre producing plant species, ranks next to cotton only. Today, biotechnological approach has been considered as most accepted means for any genetic improvement of plant species. However, genetic control of the fibre development in jute has not yet been explored sufficiently for desired genetic improvement. One of the major impediments in exploring the genetic architecture in this crop at molecular level is the availability of good quality RNA from field-grown plant tissues mostly due to the presence of high amount of mucilage and phenolics. Development of a suitable RNA isolation method is becoming essential for deciphering developmental stage-specific gene expression pattern related to fibre formation in this crop species. A combination of modified hot borate buffer followed by isopycnic centrifugation (termed as HBIC) was adopted and found to be the best isolation method yielding sufficient quantity (~350-500 μg/gm fresh tissue) and good quality (A(260/280) ratio 1.88 to 1.91) RNA depending on the developmental stage of stem tissue from field-grown jute plant. The poly A(+) RNA purified from total RNA isolated by the present method was found amenable to efficient RT-PCR and cDNA library construction. The present development of RNA isolation was found to be appropriate for gene expression analysis related to fibre formation in this economically important jute plant in near future. PMID:21327574

  11. Bioaccumulation and translocation of heavy metals by nine native plant species grown at a sewage sludge dump site.

    PubMed

    Eid, Ebrahem M; Shaltout, Kamal H

    2016-11-01

    In the present study, nine native plant species were collected to determine their potential to clean up nine heavy metals from soil of a sewage sludge dump site. Almost all nine plant species grown at sewage sludge dump site showed multifold higher concentrations of heavy metals as compared to plants grown at the reference site. All the investigated species were characterized by a bioaccumulation factor (BF) > 1.0 for some heavy metals. BF was generally higher for Cd, followed by Pb, Co, Cr, Cu, Ni, Mn, Zn, and Fe. The translocation factor (TF) varied among plant species, and among heavy metals. For most studied heavy metals, TFs were <1.0. The present study proved that the concentrations of all heavy metals (except Cd, Co, and Pb) in most studied species were positively correlated with those in soil. Such correlations indicate that these species reflect the cumulative effects of environmental pollution from soil, and thereby suggesting their potential use in the biomonitoring of most heavy metals examined. In conclusion, all tissues of nine plant species could act as bioindicators, biomonitors, and remediates of most examined heavy metals. Moreover, Bassia indica, Solanum nigrum, and Pluchea dioscoridis are considered hyperaccumulators of Fe; Amaranthus viridis and Bassia indica are considered hyperaccumulators of Pb; and Portulaca oleracea is considered hyperaccumulator of Mn. PMID:27184987

  12. Heavy Metals Accumulation of Some Plant Species Grown on Mining Area at Mahad AD`Dahab, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Al-Farraj, A. S.; Al-Wabel, M. I.

    Samples from different plants species, which grown around Mahad AD`Dahab Mine, have been selected to study their ability to accumulate these heavy metals. These plant species were: Pergularia tomentosa, Calotropis procera, Acacia tortilis, Ochradenus baccatus, Salsola sp., Rhiza strica, Convolvalus sp., Euculeptus sp., Family graminaea and Prosopis juliflora. Moreover, some of soil samples under each plant were collected. Plants and soils samples were analyzed for their contents of As, Cd, Cu, Pb and Zn. Two way ANOVA analysis without interaction was performed to examine the effect of plant species and heavy metals concentration in soil on their accumulation by plants. Although significant differences were not found at 0.01 levels among the plant species, it was found that Pergularia tomentosa was the highest to accumulate heavy metals. Considering the mean of accumulating heavy metals, plant species accumulated heavy metals by this order: Pergularia tomentosa, Euculeptus sp. Convolvalus sp. Family graminaea, Rhiza strica, Acacia tortilis, Prosopis juliflora, Salsola sp. Calotropis procera, Ochradenus baccatus. According to the mean of BAF's, heavy metals concentration of Cd was found to be significantly different than Cu, Pb and Zn. From above, these plants should be described as not-excluder and can be explored further for phytoremediation of metal polluted soils. On other hand, the practice of providing foliage and pods as fodder for live stock should be avoided in Mahad AD`Dahab area.

  13. Developmental patterns of jicama (Pachyrhizus erosus (L.) Urban) plant and the chemical constituents of roots grown in Sonora, Mexico.

    PubMed

    Fernandez, M V; Warid, W A; Loaiza, J M; Montiel, A

    1997-01-01

    The developmental pattern of jicama (Pachyrhizus erosus (L.) Urban) was studied by sampling plants aged 20 to 36 weeks at weekly intervals. There was an increase in all characteristics of foliage: fresh and dry weight, number of leaves per plant, main stem length, number of leaves, nodes and internodes of the main stem; and in all root characteristics: fresh and dry weight, diameter and length. The chemical analysis was determined for roots at different plant ages. The range values for dry matter were 16.19-22.28%, protein 1.11-1.62%, fat 0.553-0.867%, crude fiber 0.3048-0.3943%, and ash 0.669-1.089%. The chemical constituents fluctuated with age but without specific trends. These values are considered the first record of roots produced by plants grown in Mexico. PMID:9477422

  14. Contrasting Strategies of Alfalfa Stem Elongation in Response to Fall Dormancy in Early Growth Stage: The Tradeoff between Internode Length and Internode Number

    PubMed Central

    Wang, Zongli; Sun, Qizhong

    2015-01-01

    Fall dormancy (FD) in alfalfa (Medicago sativa L.) can be described using 11 FD ratings, is widely used as an important indicator of stress resistance, productive performance and spring growth. However, the contrasting growth strategies in internode length and internode number in alfalfa cultivars with different FD rating are poorly understood. Here, a growth chamber study was conducted to investigate the effect of FD on plant height, aboveground biomass, internode length, and internode number in alfalfa individuals in the early growth stages. In order to simulate the alfalfa growth environment in the early stage, 11 alfalfa cultivars with FD ratings from one to 11 were chosen and seeded at the greenhouse, and then were transplanted into an artificial growth chamber. The experimental design was a randomized complete block in a split-plot arrangement with three replicates. Plant height, above-ground biomass, internode length, and internode number were measured in early growth stage in all individuals. Our findings showed that plant height and the aboveground biomass of alfalfa did not significantly differ among 11 different FD rated cultivars. Also, internode length and internode number positively affected plant height and the aboveground biomass of alfalfa individuals and the average internode length significantly increased with increasing FD rating. However, internode number tended to sharply decline when the FD rating increased. Moreover, there were no correlations, slightly negative correlations, and strongly negative correlations between internode length and internode number in alfalfa individuals among the three scales, including within-FD ratings, within-FD categories and inter-FD ratings, respectively. Therefore, our results highlighted that contrasting growth strategies in stem elongation were adopted by alfalfa with different FD ratings in the early growth stage. Alfalfa cultivars with a high FD rating have longer internodes, whereas more dormant alfalfa

  15. Identification of Dehydration Responsive Genes from Two Non-Nodulated Alfalfa Cultivars Using Medicago Truncatula Microarrays

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To have a comprehensive understanding of how legume plants respond to drought at the gene expression level and examine whether legume plants that are not fixing nitrogen would behave similar to non-legume plants in drought response, transcriptomes were studied in two non-nodulated alfalfa (Medicago ...

  16. First report of Alfalfa mosaic virus infecting basil (Ocimum basilicum L.) in California.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Basil (Ocimum basilicum L.) plants collected from a field in Imperial County, CA in May, 2011 were found to exhibit yellowing, chlorotic sectors and spots on leaves, resulting in plants being unmarketable. Total nucleic acid was extracted from plants and tested by RT-PCR for the presence of Alfalfa...

  17. Effects of tabtoxinine-. beta. -lactam treatments on alfalfa

    SciTech Connect

    Margiotta, E.A.; Weaver, L.M.; Unkefer, P.J. )

    1991-05-01

    Tabtoxinine-{beta}-lactam (T{beta}L), excreted by the tobacco pathogen Pseudomonas syringae pv. tabaci, is an active site directed, irreversible inhibitor of the enzyme glutamine synthetase (GS) (E.C.6.3.2.1). Previously, we have shown infestation of the alfalfa rhizosphere with Pseudomonas syringae pv. tabaci results in selective impairment of GS and increased plant growth and nodule number. We have now shown purified T{beta}L, when administered to alfalfa roots, can produce the same effects as colonization of the rhizosphere with P. syringae pv. tabaci. Results of GS specific activity, nitrogen fixation as measured by acetylene reduction, and plant growth response to T{beta}L dosage are presented.

  18. Assessing disease stress and modeling yield losses in alfalfa

    NASA Astrophysics Data System (ADS)

    Guan, Jie

    weight, percentage reflectance (810 nm), and green leaf area index (GLAI). Percentage reflectance (810 nm) assessments had a stronger relationship with dry weight and green leaf area index than percentage defoliation assessments. Our research conclusively demonstrates that percentage reflectance measurements can be used to nondestructively assess green leaf area index which is a direct measure of plant health and an indirect measure of productivity. This research conclusively demonstrates that remote sensing is superior to visual assessment method to assess alfalfa stress and to model yield and GLAI in the alfalfa foliar disease pathosystem.

  19. Genome-Wide Expression Analysis of Reactive Oxygen Species Gene Network in Mizuna Plants Grown in Long-Term Spaceflight

    NASA Astrophysics Data System (ADS)

    Sugimoto, Manabu; Gusev, Oleg; Wheeler, Raymond; Levinskikh, Margarita; Sychev, Vladimir; Bingham, Gail; Hummerick, Mary; Oono, Youko; Matsumoto, Takashi; Yazawa, Takayuki

    We have developed a plant growth system, namely Lada, which was installed in ISS to study and grow plants, including vegetables in a spaceflight environment. We have succeeded in cultivating Mizuna, tomato, pea, radish, wheat, rice, and barley in long-term spaceflight. Transcription levels of superoxide dismutase, glutamyl transferase, catalase, and ascorbate peroxidase were increased in the barley germinated and grown for 26 days in Lada, though the whole-plant growth and development of the barley in spaceflight were the same as in the ground control barley. In this study, we investigated the response of the ROS gene network in Mizuna, Brassica rapa var. nipposinica, cultivated under spaceflight condition. Seeds of Mizuna were sown in the root module of LADA aboard the Zvezda module of ISS and the seedlings were grown under 24h lighting in the leaf chamber. After 27 days of cultivation, the plants were harvested and stored at -80(°) C in MELFI aboard the Destiny module, and were transported to the ground at < -20(°) C in GLACIER aboard Space Shuttle. Ground control cultivation was carried out under the same conditions in LADA. Total RNA isolated from leaves was subjected to mRNA-Seq using next generation sequencing (NGS) technology. A total of 20 in 32 ROS oxidative marker genes were up-regulated, including high expression of four hallmarks, and preferentially expressed genes associated with ROS-scavenging including thioredoxin, glutaredoxin, and alternative oxidase genes. In the transcription factors of the ROS gene network, MEKK1-MKK4-MPK3, OXI1-MKK4-MPK3, and OXI1-MPK3 of MAP cascades, induction of WRKY22 by MEKK1-MKK4-MPK3 cascade, induction of WRKY25 and repression of Zat7 by Zat12 were suggested. These results revealed that the spaceflight environment induced oxidative stress and the ROS gene network activation in the space-grown Mizuna.

  20. Response of Two Plant Species to Two Ultraviolet-B Radiation Regimes

    NASA Technical Reports Server (NTRS)

    Levy, Daniel L.; Skiles, J. W.; Peterson, David (Technical Monitor)

    1996-01-01

    The depleted stratospheric ozone layer has been directly linked to increased levels of ultraviolet radiation at the earth's surface. It is important to understand what effect this will have on plants. We tested the hypothesis that in response to increased UV-B radiation (280-320 man), soybean (Glycine max Merrill) and alfalfa (Mercado Saliva L.) would produce higher concentrations of flavonoids than plants screened from UV-B. Soybean and alfalfa plants were grown successively in a growth chamber that provided UV-B radiation intensities 45% above summer field levels. A wooden frame was used to suspend mylar-D film over one group of plants and mono-acetate film over another group. Mylar is opaque in the 280-316 nm range, and acetate absorbs most radiation from 280-290 nm and then reduces intensities in the 290-320 nm range by roughly 15%. Leaf chlorophyll concentration was determined with a Minolta SPAD-502 chlorophyll meter; the BRAD meter was calibrated with N,N- extractions. Flavonoids were extracted with an acidified methanol/water solution. Soybean grown under the acetate treatment showed 26% smaller internodal lengths and higher concentrations of flavonoids compared to plants grown under mylar. Significant results for alfalfa included 22% greater leaf flavonoid concentration under acetate, 14% greater leaf chlorophyll concentration under mylar, and 32% greater above-ground biomass under mylar. We found that increased UV-B radiation leads to increased production of UV-B absorbing compounds (i.e. flavonoids) in soybean and alfalfa leaves. This suggests that a protective mechanism in these plants is triggered by UV-B. In response, flavonoids are produced that absorb UV-B, and consequently decrease potentially damaging effects to the plants. In addition, we hypothesize that this flavonoid protection mechanism saturates at certain UV-B intensities.

  1. Anatomical features of pepper plants (Capsicum annuum L.) grown under red light-emitting diodes supplemented with blue or far-red light

    NASA Technical Reports Server (NTRS)

    Schuerger, A. C.; Brown, C. S.; Stryjewski, E. C.

    1997-01-01

    Pepper plants (Capsicum annuum L. cv., Hungarian Wax) were grown under metal halide (MH) lamps or light-emitting diode (LED) arrays with different spectra to determine the effects of light quality on plant anatomy of leaves and stems. One LED (660) array supplied 90% red light at 660 nm (25nm band-width at half-peak height) and 1% far-red light between 700-800nm. A second LED (660/735) array supplied 83% red light at 660nm and 17% far-red light at 735nm (25nm band-width at half-peak height). A third LED (660/blue) array supplied 98% red light at 660nm, 1% blue light between 350-550nm, and 1% far-red light between 700-800nm. Control plants were grown under broad spectrum metal halide lamps. Plants were gron at a mean photon flux (300-800nm) of 330 micromol m-2 s-1 under a 12 h day-night photoperiod. Significant anatomical changes in stem and leaf morphologies were observed in plants grown under the LED arrays compared to plants grown under the broad-spectrum MH lamp. Cross-sectional areas of pepper stems, thickness of secondary xylem, numbers of intraxylary phloem bundles in the periphery of stem pith tissues, leaf thickness, numbers of choloplasts per palisade mesophyll cell, and thickness of palisade and spongy mesophyll tissues were greatest in peppers grown under MH lamps, intermediate in plants grown under the 660/blue LED array, and lowest in peppers grown under the 660 or 660/735 LED arrays. Most anatomical features of pepper stems and leaves were similar among plants grown under 660 or 660/735 LED arrays. The effects of spectral quality on anatomical changes in stem and leaf tissues of peppers generally correlate to the amount of blue light present in the primary light source.

  2. Stable isotope analysis of plant-derived nitrate - novel method for discrimination between organically and conventionally grown vegetables.

    PubMed

    Mihailova, A; Pedentchouk, N; Kelly, S D

    2014-07-01

    The lack of reliable markers for the discrimination between organic and conventional products makes the organic food market susceptible to attempted fraud. Robust analytical methodologies for organic food authentication are urgently needed. In this study a new approach, compound-specific nitrogen and oxygen isotope analysis of plant-derived nitrate, has been applied alongside bulk nitrogen isotope analysis for discrimination between organically and conventionally greenhouse-grown lettuce and retail potatoes and tomatoes. The method revealed significant differences between conventional and organic fertilisation. An intra-plant isotopic variation as well as significant impact of the fertiliser application rate on the nitrogen and oxygen isotope values of plant-derived nitrate has been observed. Nitrogen and oxygen isotope analysis of nitrate has a potential for differentiation between organic and conventional crops. Further analysis is needed to improve our understanding of the scope of application and robustness of this compound-specific approach. PMID:24518338

  3. Novel components of leaf bacterial communities of field-grown tomato plants and their potential for plant growth promotion and biocontrol of tomato diseases.

    PubMed

    Romero, Fernando M; Marina, María; Pieckenstain, Fernando L

    2016-04-01

    This work aimed to characterize potentially endophytic culturable bacteria from leaves of cultivated tomato and analyze their potential for growth promotion and biocontrol of diseases caused by Botrytis cinerea and Pseudomonas syringae. Bacteria were obtained from inner tissues of surface-disinfected tomato leaves of field-grown plants. Analysis of 16S rRNA gene sequences identified bacterial isolates related to Exiguobacterium aurantiacum (isolates BT3 and MT8), Exiguobacterium spp. (isolate GT4), Staphylococcus xylosus (isolate BT5), Pantoea eucalypti (isolate NT6), Bacillus methylotrophicus (isolate MT3), Pseudomonas veronii (isolates BT4 and NT2), Pseudomonas rhodesiae (isolate BT2) and Pseudomonas cichorii (isolate NT3). After seed inoculation, BT2, BT4, MT3, MT8, NT2 and NT6 were re-isolated from leaf extracts. NT2, BT2, MT3 and NT6 inhibited growth of Botrytis cinerea and Pseudomonas syringae pv. tomato in vitro, produced antimicrobial compounds and reduced leaf damage caused by B. cinerea. Some of these isolates also promoted growth of tomato plants, produced siderophores, the auxin indole-3-acetic and solubilized inorganic phosphate. Thus, bacterial communities of leaves from field-grown tomato plants were found to harbor potentially endophytic culturable beneficial bacteria capable of antagonizing pathogenic microorganisms and promoting plant growth, which could be used as biological control agents and biofertilizers/biostimulators for promotion of tomato plant growth. PMID:26654914

  4. Quantitation of pyrimidine dimers in DNA from UVB-irradiated alfalfa (@ L. ) seedlings

    SciTech Connect

    Quaite, F.E.; Sutherland, B.M.; Sutherland, J.C.

    1991-01-01

    Depletion of stratospheric ozone will increase the solar ultraviolet radiation in the range from 290-320 nm (UVB) that reaches the surface of the earth, placing an increased UV burden on exposed organisms. One consequence of increased UVB may be decreased productivity of crop plants. A principal lesion caused by UV in DNA is the cyclobutyl pyrimidine dimer. We have adapted a method for measuring these dimers in nanogram quantities of non-radioactive DNA for use in UV-irradiated plants. We find that biologically relevant doses of broad band UVB radiation induce easily detectable frequencies of pyrimidine dimers in the DNA of irradiated alfalfa sprout leaves and that the dose response for dimer formation is linear up to doses of at least 690 J/m{sup 2}. We also find easily measurable frequencies of dimers in the leaves of seedlings grown in glass filtered sunlight but not exposed to additional UVB, suggesting that significant number of dimers are formed in plants exposed to normal sunlight. 27 refs., 3 figs., 1 tab.

  5. Modifications of Morphometrical and Physiological Parameters of Pepper Plants Grown on Artificial Nutrient Medium for Experiments in Spaceflight

    NASA Astrophysics Data System (ADS)

    Nechitailo, Galina S.

    2016-07-01

    MODIFICATIONS OF MORPHOMETRICAL AND PHYSIOLOGICAL PARAMETERS OF PEPPER PLANTS GROWN ON ARTIFICIAL NUTRIENT MEDIUM FOR EXPERIMENTS IN SPACEFLIGHT Lui Min*, Zhao Hui*, Chen Yu*, Lu Jinying*, Li Huasheng*, Sun Qiao*, Nechitajlo G.S.**, Glushchenko N.N.*** *Shenzhou Space Biotechnology Group, China Academy of Space Technology (CAST), **Emanuel Institute of Biochemical Physics of Russian Academy of Sciences (IBCP RAS) mail: spacemal@mail.ru ***V.L. Talrose Institute for Energy Problems of Chemical Physics of Russian Academy of Science (INEPCP RAS) mail: nnglu@ mail.ru In circumstances of space flights, long residence of the staff at space stations and space settlements an optimal engineering system of the life-support allowing to solve a number of technical and psychological problems for successful work and a life of cosmonauts, researchers, etc. is important and prime. In this respect it is necessary to consider growing plants on board of spacecraft as one of the units in a life-support system. It is feasible due to modern development of biotechnologies in growing plants allowing us to receive materials with new improved properties. Thus, a composition and ratio of components of nutrient medium can considerably influence on plants properties. We have developed the nutrient medium in which essential metals such as iron, zinc, copper were added in an electroneutral state in the form of nanoparticles instead of sulfates or other salts of the same metals. Such replacement is appropriate through unique nanoparticles properties: metal nanoparticles are less toxic than their corresponding ionic forms; nanoparticles produce a prolonged effect, serving as a depot for elements in an organism; nanoparticles introduced in biotic doses stimulate the metabolic processes of the organism; nanoparticles effect is multifunctional. Pepper strain LJ-king was used for growing on a nutrient medium with ferrous, zinc, copper nanoparticles in different concentrations. Pepper plants grown on

  6. CCROP-Simulation model for container-grown nursery plant production.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Container Crop Resource Optimization Program (CCROP) is an integrative model which simulates the growth and water and nutrient requirements of a woody ornamental shrub grown in small (2.8–11.4 L) containers in a field environment with overhead sprinkler irrigation. The model was developed for produc...

  7. Cytological and Other Aspects of Pathogenesis-related Gene Expression in Tomato Plants Grown on a Suppressive Compost

    PubMed Central

    KAVROULAKIS, NEKTARIOS; PAPADOPOULOU, KALLIOPE K.; NTOUGIAS, SPYRIDON; ZERVAKIS, GEORGIOS I.; EHALIOTIS, CONSTANTINOS

    2006-01-01

    • Background and Aims Recent studies have shown that certain composts may trigger indirect defence mechanisms by sensitizing the plant to create an increased state of resistance, similar to systemic acquired resistance. In this study, the capacity of a disease-suppressive compost to alter the expression pattern of certain pathogenesis-related (PR) genes in the root system of tomato plants (Solanum lycopersicum) provided the opportunity to study their cellular expression pattern and to investigate putative roles of these genes in the mechanisms of plant defence. • Methods Employing the reverse transcription–polymerase chain reaction (RT–PCR) and in situ RNA:RNA hybridization techniques, the accumulation and distribution of the transcripts of the differentially expressed PR genes were examined in plants grown on compost and compared with those of control plants grown on peat. • Key Results Elevated levels of expression of the pathogenesis-related genes PR-1, PR-5 and P69/PR-7 were detected in the roots of tomato plants grown on the compost. A clearly distinguished spatial induction pattern was observed for these PR genes: PR-1 transcripts were almost exclusively detected in the pericycle cells surrounding the root stele of the main and lateral roots; PR-5 transcripts were present in the phloem of the root and stem tissues; and the accumulation and distribution of PR-7 transcripts was detected in discrete groups of cells that appeared sporadically in both the parenchyma and vascular system of the root, suggesting that the gene is not expressed in a tissue-specific manner. In addition, a novel cDNA clone was isolated (P69G), which probably encodes a new tomato P69 isoform. • Conclusions This study provides evidence that a supressive compost is able to elicit consistent and increased expression of certain PR genes in the roots of tomato plants, even in the absence of any pathogen. The in situ localization studies reveal expression patterns which are in

  8. Effects of ozone and water stress on canopy temperature, water use, and water-use efficiency of alfalfa

    SciTech Connect

    Temple, P.J.; Benoit, L.F.

    1988-01-01

    Ozone (O/sub 3/) and soil water deficit are two environmental stresses that significantly affect the growth and yield of alfalfa. However, little is known of the responses of field-grown alfalfa to O/sub 3/, and the effects of the interaction between O/sub 3/ and water stress on canopy temperature and water relations of alfalfa have not been previously reported. Water use, rate of soil-water depletion, or depth of effective rooting zone were not affected by O/sub 3/, whereas water stress significantly reduced all three. Water-use efficiency was significantly reduced by O/sub 3/. The effects of O/sub 3/ on WUE were attributed to premature senescence and abscission of older alfalfa leaves.

  9. Interactions Among Selected Endoparasitic Nematodes and Three Pseudomonads on Alfalfa

    PubMed Central

    Bookbinder, M. G.; Bloom, J. R.; Lukezic, F. L.

    1982-01-01

    Meloidogyne hapla, Pratylenchus penetrans, and Helicotylenchus dihystera, reduced the growth of 'Saranac AR alfalfa seedlings when applied at concentrations of 50 nematodes per plant. All except P. penetrans reduced seedling growth when applied at 25 per seedling. M. hapla reduced growth when applied at 12 per seedling. Nematodes interacted with three pseudomonads to produce greater growth reductions than were obtained with single pathogens, suggesting synergistic relationships. Ditylenchus dipsaci, applied at 25 or 50 nematodes per seedling, reduced plant weight compared with weights of control plants, but did not interact with test bacteria. All of the nematodes except D. dipsaci produced root wounds which were invaded by bacteria. PMID:19295682

  10. Photomorphogenesis, photosynthesis, and seed yield of wheat plants grown under red light-emitting diodes (LEDs) with and without supplemental blue lighting.

    PubMed

    Goins, G D; Yorio, N C; Sanwo, M M; Brown, C S

    1997-07-01

    Red light-emitting diodes (LEDs) are a potential light source for growing plants in spaceflight systems because of their safety, small mass and volume, wavelength specificity, and longevity. Despite these attractive features, red LEDs must satisfy requirements for plant photosynthesis and photomorphogenesis for successful growth and seed yield. To determine the influence of gallium aluminium arsenide (GaAlAs) red LEDs on wheat photomorphogenesis, photosynthesis, and seed yield, wheat (Triticum aestivum L., cv. 'USU-Super Dwarf') plants were grown under red LEDs and compared to plants grown under daylight fluorescent (white) lamps and red LEDs supplemented with either 1% or 10% blue light from blue fluorescent (BF) lamps. Compared to white light-grown plants, wheat grown under red LEDs alone demonstrated less main culm development during vegetative growth through preanthesis, while showing a longer flag leaf at 40 DAP and greater main culm length at final harvest (70 DAP). As supplemental BF light was increased with red LEDs, shoot dry matter and net leaf photosynthesis rate increased. At final harvest, wheat grown under red LEDs alone displayed fewer subtillers and a lower seed yield compared to plants grown under white light. Wheat grown under red LEDs+10% BF light had comparable shoot dry matter accumulation and seed yield relative to wheat grown under white light. These results indicate that wheat can complete its life cycle under red LEDs alone, but larger plants and greater amounts of seed are produced in the presence of red LEDs supplemented with a quantity of blue light. PMID:11541074

  11. Salicornia strobilacea (Synonym of Halocnemum strobilaceum) Grown under Different Tidal Regimes Selects Rhizosphere Bacteria Capable of Promoting Plant Growth

    PubMed Central

    Marasco, Ramona; Mapelli, Francesca; Rolli, Eleonora; Mosqueira, Maria J.; Fusi, Marco; Bariselli, Paola; Reddy, Muppala; Cherif, Ameur; Tsiamis, George; Borin, Sara; Daffonchio, Daniele

    2016-01-01

    Halophytes classified under the common name of salicornia colonize salty and coastal environments across tidal inundation gradients. To unravel the role of tide-related regimes on the structure and functionality of root associated bacteria, the rhizospheric soil of Salicornia strobilacea (synonym of Halocnemum strobilaceum) plants was studied in a tidal zone of the coastline of Southern Tunisia. Although total counts of cultivable bacteria did not change in the rhizosphere of plants grown along a tidal gradient, significant differences were observed in the diversity of both the cultivable and uncultivable bacterial communities. This observation indicates that the tidal regime is contributing to the bacterial species selection in the rhizosphere. Despite the observed diversity in the bacterial community structure, the plant growth promoting (PGP) potential of cultivable rhizospheric bacteria, assessed through in vitro and in vivo tests, was equally distributed along the tidal gradient. Root colonization tests with selected strains proved that halophyte rhizospheric bacteria (i) stably colonize S. strobilacea rhizoplane and the plant shoot suggesting that they move from the root to the shoot and (ii) are capable of improving plant growth. The versatility in the root colonization, the overall PGP traits and the in vivo plant growth promotion under saline condition suggest that such beneficial activities likely take place naturally under a range of tidal regimes. PMID:27597846

  12. Salicornia strobilacea (Synonym of Halocnemum strobilaceum) Grown under Different Tidal Regimes Selects Rhizosphere Bacteria Capable of Promoting Plant Growth.

    PubMed

    Marasco, Ramona; Mapelli, Francesca; Rolli, Eleonora; Mosqueira, Maria J; Fusi, Marco; Bariselli, Paola; Reddy, Muppala; Cherif, Ameur; Tsiamis, George; Borin, Sara; Daffonchio, Daniele

    2016-01-01

    Halophytes classified under the common name of salicornia colonize salty and coastal environments across tidal inundation gradients. To unravel the role of tide-related regimes on the structure and functionality of root associated bacteria, the rhizospheric soil of Salicornia strobilacea (synonym of Halocnemum strobilaceum) plants was studied in a tidal zone of the coastline of Southern Tunisia. Although total counts of cultivable bacteria did not change in the rhizosphere of plants grown along a tidal gradient, significant differences were observed in the diversity of both the cultivable and uncultivable bacterial communities. This observation indicates that the tidal regime is contributing to the bacterial species selection in the rhizosphere. Despite the observed diversity in the bacterial community structure, the plant growth promoting (PGP) potential of cultivable rhizospheric bacteria, assessed through in vitro and in vivo tests, was equally distributed along the tidal gradient. Root colonization tests with selected strains proved that halophyte rhizospheric bacteria (i) stably colonize S. strobilacea rhizoplane and the plant shoot suggesting that they move from the root to the shoot and (ii) are capable of improving plant growth. The versatility in the root colonization, the overall PGP traits and the in vivo plant growth promotion under saline condition suggest that such beneficial activities likely take place naturally under a range of tidal regimes. PMID:27597846

  13. From fresh vegetables to the harvest of wheat plants grown in the "SVET" space greenhouse onboard the MIR orbital station

    NASA Technical Reports Server (NTRS)

    Ivanova, T.; Kostov, P.; Sapunova, S.; Dandolov, I.; Sytchev, V.; Podolski, I.; Levinskikh, M.; Meleshko, G.; Bingham, G.; Salisbury, F.

    1997-01-01

    Researchers report the results of experiments conducted onboard MIR in 1990, 1995, and 1996 in raising edible crops. In the 1990 experiment, radishes and Chinese cabbage were grown successfully, though the experimental plants were up to four times smaller than controls at harvest. The 1995 experiment in growing wheat through a complete life cycle was not completed. The 1996 experiment was successful in growing wheat through a complete life cycle to the seed stage. No seeds developed on any of the 279 ears harvested in that experiment. Reasons for the seedless development are explored.

  14. Abundance of rice root aphid among selected plant species and on plants grown with different soil-surface media

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rice root aphid, Rhopalosiphum rufiabdominalis (Sasaki), is distributed worldwide and colonizes a wide range of plants. However, relatively little is known about the suitability of different host plants, optimal rearing techniques, and the aphid’s impact on plant fitness. To improve understand...

  15. The Sinorhizobium meliloti RNA chaperone Hfq influences central carbon metabolism and the symbiotic interaction with alfalfa

    PubMed Central

    2010-01-01

    Background The bacterial Hfq protein is able to interact with diverse RNA molecules, including regulatory small non-coding RNAs (sRNAs), and thus it is recognized as a global post-transcriptional regulator of gene expression. Loss of Hfq has an extensive impact in bacterial physiology which in several animal pathogens influences virulence. Sinorhizobium meliloti is a model soil bacterium known for its ability to establish a beneficial nitrogen-fixing intracellular symbiosis with alfalfa. Despite the predicted general involvement of Hfq in the establishment of successful bacteria-eukaryote interactions, its function in S. meliloti has remained unexplored. Results Two independent S. meliloti mutants, 2011-3.4 and 1021Δhfq, were obtained by disruption and deletion of the hfq gene in the wild-type strains 2011 and 1021, respectively, both exhibiting similar growth defects as free-living bacteria. Transcriptomic profiling of 1021Δhfq revealed a general down-regulation of genes of sugar transporters and some enzymes of the central carbon metabolism, whereas transcripts specifying the uptake and metabolism of nitrogen sources (mainly amino acids) were more abundant than in the wild-type strain. Proteomic analysis of the 2011-3.4 mutant independently confirmed these observations. Symbiotic tests showed that lack of Hfq led to a delayed nodulation, severely compromised bacterial competitiveness on alfalfa roots and impaired normal plant growth. Furthermore, a large proportion of nodules (55%-64%) elicited by the 1021Δhfq mutant were non-fixing, with scarce content in bacteroids and signs of premature senescence of endosymbiotic bacteria. RT-PCR experiments on RNA from bacteria grown under aerobic and microoxic conditions revealed that Hfq contributes to regulation of nifA and fixK1/K2, the genes controlling nitrogen fixation, although the Hfq-mediated regulation of fixK is only aerobiosis dependent. Finally, we found that some of the recently identified S. meliloti s

  16. Effects of phosphate and thiosulphate on arsenic accumulation in Brassica juncea plants grown in soil and in hydroponic culture

    NASA Astrophysics Data System (ADS)

    Pezzarossa, Beatrice; Petruzzelli, Gianniantonio; Grifoni, Martina; Rosellini, Irene; Malagoli, Mario; Schiavon, Michela

    2013-04-01

    Arsenic is recognised as a toxic metalloid and a strong pollutant in soils of many countries. Thus, the reclamation of contaminated areas is fundamental in order to protect both human health and agricultural production. This study is focused on the assisted phytoextraction, a technology for reclaiming polluted soils that takes advantage of the capability of some plants to extract inorganic elements from soils with the aid of additive agents. The nutrients phosphorus, as phosphate, and sulphur, as thiosulphate, can compete with the form more oxidised of arsenic, both in soil and plant. This study examined the capability of thiosulphate (Th) and phosphate (Ph) to promote the release of As from soil surfaces in order to improve the phytoavailability and thus the absorption of As by Brassica juncea plants. In the first experiment B. juncea plants were grown on a soil that had been sampled from an industrial area strongly contaminated by As (790 mg As kg-1 soil). The second experiment was carried out in hydroponics where As has been added at a concentration (100 microM) similar to the As available concentration measured in soil. In both trials ammonium thiosulphate (at the concentration of 0.27 M in soil, and 400 microM in hydroponics) and potassium hydrogen phosphate (at the concentration of 0.05 M in soil, and 112 microM in hydroponics) were added. The biomass of B. juncea was determined and the accumulation of P, S and As in root and in the above-ground tissues have been analyzed. Our results showed that thiosulphate and phosphate acted either as nutrients and detoxifying agents, due to the stimulation of plant defensive systems, and influenced either the biomass production and the As accumulation in plant tissues. In the plants grown in soil, As accumulated at higher levels in the above-ground part than in the roots and the addition of Th induced a higher biomass production and a higher total As accumulation (concentration x biomass) in the above-ground tissues

  17. EFFECTS OF SIMULATED ACIDIC RAIN ON YIELDS OF FIELD-GROWN CROPS

    EPA Science Inventory

    Experiments were performed to determine the effects of simulated acidic rainfall on yields of radish (Raphanus sativa), garden beet (Beta vulgaris), kidney bean (Phaseolus vulgaris), and alfalfa (Medicago sativa) grown under standard agronomic practices. The experimental design a...

  18. Local production of agricultural fuel: conversion of alfalfa to ethanol. Final report

    SciTech Connect

    Nelson, D.; Tjostem, J.; Koeltzow, D.E.

    1981-09-01

    Initial project goals were to determine the economic and technological feasibility of producing fuel grade ethanol from the sugars contained in alfalfa and other legumes using a small-scale, single-farm production facility. These data indicate that alfalfa from the field does have reducing sugar present before any breakdown due to the presence of the mold. There is also plenty of natural bacterial contamination which quickly depletes the sugar supply. However, if the alfalfa is autoclaved prior to incubation, the number of bacteria present in the samples is greatly reduced. There was no difference between the flasks which contained an inoculum of Tricoderma reesei and those that did not. Analysis of these solutions failed to show any trace of cellulase activity even after 288 hours (12 days). Therefore, one can also conclude that the Tricoderma reesei strain QM9414 does not grow on alfalfa under these conditions. Future experiments will involve different conditions of temperature and pH. Acid insoluble lignin levels in our 3rd cutting alfalfa samples range from 16.8% to 19.77% with an average of 18.3%. This agrees well with the levels of 13.8% and 15.9% reported by Linder, et al. Results of lipid, water, protein, lignin and cellulose analysis of alfalfa are given. Over 80% of the cellulose in alfalfa can be converted into glucose. Subsequent fermentation by S. carlisbergenois produced near theoretical yields of ethanol. However, the cost of the hay was $440.00; the market value of the ethanol was $120.00. The poor economics results since only 13.1% of the alfalfa contains cellulose. Results show that while production of ethanol from legume-type plants is technically possible, it is not economically feasible.

  19. Mercury uptake and phytotoxicity in terrestrial plants grown naturally in the Gumuskoy (Kutahya) mining area, Turkey.

    PubMed

    Sasmaz, Merve; Akgül, Bunyamin; Yıldırım, Derya; Sasmaz, Ahmet

    2016-01-01

    This study investigated mercury (Hg) uptake and transport from the soil to different plant parts by documenting the distribution and accumulation of Hg in the roots and shoots of 12 terrestrial plant species, all of which grow naturally in surface soils of the Gumuskoy Pb-Ag mining area. Plant samples and their associated soils were collected and analyzed for Hg content by ICP-MS. Mean Hg values in the soils, roots, and shoots of all plants were 6.914, 460, and 206 µg kg(-1), respectively and lower than 1. The mean enrichment factors for the roots (ECR) and shoots (ECS) of these plants were 0.06 and 0.09, respectively and lower than 1. These results show that the roots of the studied plants prevented Hg from reaching the aerial parts of the plants. The mean translocation factor (TLF) was 1.29 and higher than 1. The mean TLF values indicated that all 12 plant species had the ability to transfer Hg from the roots to the shoots but that transfer was more efficient in plants with higher ECR and ECS. Therefore, these plants could be useful for the biomonitoring of environmental pollution and for rehabilitating areas contaminated by Hg. PMID:26114359

  20. Prohexadione-calcium improves the establishment and yield of alfalfa interseeded as a dual purpose cover-forage crop into silage corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interseeded alfalfa could serve as a dual purpose crop for providing groundcover during silage corn production and forage during subsequent years of production, but this system has been unworkable because competition between the co-planted crops often leads to stand failure of interseeded alfalfa an...

  1. Effect of silicon addition on soybean (Glycine max) and cucumber (Cucumis sativus) plants grown under iron deficiency.

    PubMed

    Gonzalo, María José; Lucena, Juan J; Hernández-Apaolaza, Lourdes

    2013-09-01

    Silicon is considered an essential element in several crops enhancing growth and alleviating different biotic and abiotic stresses. In this work, the role of Si in the alleviation of iron deficiency symptoms and in the Fe distribution in iron deficient plants has been studied. Thus, soybean and cucumber plants grown in hydroponic culture under iron limiting conditions were treated with different Si doses (0.0, 0.5 and 1.0 mM). The use of a strong chelating agent such as HBED avoided Fe co-precipitation in the nutrient solution and allowed for the first time the analysis of Si effect in iron nutrition without the interference of the iron rhizospheric precipitation. SPAD index, plant growth parameters and mineral content in plant organs were determined. For soybean, the addition of 0.5 mM of Si to the nutrient solution without iron, initially or continuously during the experiment, prevented the chlorophyll degradation, slowed down the growth decrease due to the iron deficiency and maintained the Fe content in leaves. In cucumber, Si addition delayed the decrease of stem dry weight, stem length, node number and iron content in stems and roots independently of the dose, but no-effect was observed in chlorosis symptoms alleviation in leaves. The observed response to Si addition in iron deficiency was plant-specific, probably related with the different Fe efficiency strategies developed by these two species. PMID:23845824

  2. Potato leafhopper (Hemiptera: Cicadellidae) ecology and integrated pest management focused on alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge to date on biology of the potato leafhopper, Empoasca fabae (Harris), is summarized, including geographic distribution, development, migration, agricultural host plants, and the mechanism of injury to host plants. Damage to alfalfa, potato, soybean and snap bean, as well as treatment guide...

  3. Divergent alfalfa root system architecture is maintained across environment and nutrient supply

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant root system architecture can alter and be altered by soil fertility and other environmental conditions. In soils with suboptimal fertility, plant root length often is correlated with P and K uptake because these nutrients are supplied by diffusion. We developed alfalfa (Medicago sativa L.) pop...

  4. Redesigning alfalfa to reduce protein losses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is often referred to as the “Queen of Forages” due to its relatively good digestibility, high protein, and ability to readily fix nitrogen. But there’s a big drawback to alfalfa – much of its protein is lost during the harvest and ensiling process, and more is lost in the rumen of livestock....

  5. Alfalfa (Medicago sativa ssp. sativa (L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is known as the “Queen of the Forages” as it is primarily used as animal feed for dairy cows, beef cattle, horses, sheep, chickens and other domesticated animals. Alfalfa is the forage of choice due to its high feed value and high biomass production along with its ease of establishment; res...

  6. The Tradeoff Between Alfalfa Yield and Quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extensive cutting management research has documented the effects of date and frequency of harvest on alfalfa (Medicago sativa L.) forage yield and quality. Information is lacking, however, on the change in quality relative to yield that occurs as alfalfa matures within individual harvest periods. ...

  7. Past and Present Management of Alfalfa Bees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter covers the history of alfalfa pollination by bees. The management of alkali bees, Nomia melanderi, and alfalfa leafcutting bees, Megachile rotundata, is described. Concerns surrounding the current and future use of these bee species as commercial pollinators are discussed....

  8. Effect of arbuscular mycorrhizal (AM) fungi on 137Cs uptake by plants grown on different soils.

    PubMed

    Vinichuk, M; Mårtensson, A; Ericsson, T; Rosén, K

    2013-01-01

    The potential use of mycorrhiza as a bioremediation agent for soils contaminated by radiocesium was evaluated in a greenhouse experiment. The uptake of (137)Cs by cucumber, perennial ryegrass, and sunflower after inoculation with a commercial arbuscular mycorrhizal (AM) product in soils contaminated with (137)Cs was investigated, with non-mycorrhizal quinoa included as a "reference" plant. The effect of cucumber and ryegrass inoculation with AM fungi on (137)Cs uptake was inconsistent. The effect of AM fungi was most pronounced in sunflower: both plant biomass and (137)Cs uptake increased on loamy sand and loamy soils. The total (137)Cs activity accumulated within AM host sunflower on loamy sand and loamy soils was 2.4 and 3.2-fold higher than in non-inoculated plants. Although the enhanced uptake of (137)Cs by quinoa plants on loamy soil inoculated by the AM fungi was observed, the infection of the fungi to the plants was not confirmed. PMID:22939950

  9. Warming does not stimulate mitochondrial respiration and it responds to leaf carbohydrates availability in soybean plants grown under elevated CO2 concentrations

    NASA Astrophysics Data System (ADS)

    Ruiz Vera, U. M.; Gomez-Casanovas, N.; Bernacchi, C.; Ort, D. R.; Siebers, M.

    2015-12-01

    There is a lack of understanding on the mechanism underlying the response of mitochondrial respiration (Rs) to the single and combined effects of increasing CO2 concentration ([CO2]) and warming. We investigated the response of Rs to the single and combined effects of elevated [CO2] and warming in soybean plants over a complete growing season using Temperature by Free Air CO2 enrichment technology under field conditions. The treatments were: control, elevated [CO2] (eC), high temperature (eT), and elevated [CO2]+high temperature (eT+eC). Given that photosynthetic rates in eT+eC grown plants were not higher than in plants grown under eC, we hypothesized that Rs would increase only slightly in plants grown under eT+eC compared to eC plants, due to the increase of temperature. Contrary to our prediction, our preliminary results showed that plants grown under the warming treatments had low Rs, thus eT+eC had lower Rs than eC. The response of Rs to these factors was consistent at two different plant high levels (canopy and five nodes down the canopy). Changes in Rs were explained by variations in the carbohydrate content. Our results indicate that the response of Rs to changes in [CO2] and temperature will depend on the carbohydrate availability of plant tissues and thus on how photosynthesis is affected by this environmental factors.

  10. Combined effects of CO2 enrichment, changes in diurnal light level and water stress on foliar metabolites of potato plants grown in naturally sunlit controlled environment chambers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato plants (Solanum tuberosum L. cv Kennebec) were grown in outdoor, naturally sunlit, soil-plant-atmosphere research (SPAR) chambers. Drought treatments were imposed at post-tuber initiation stage to assess water stress effects on leaf metabolites, and interactions with enriched CO2 concentrati...

  11. Plant response of onion cultivars developed from greenhouse-grown transplants to plant density and fertilizer rate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Onions (Allium cepa L.) can be established from seed or transplants. The latter planting material can be dormant or actively growing when transplanted to the field. Onion transplants can be produced in a greenhouse, but there are gaps in the knowledge of the cultural requirements for these plants ...

  12. Short-term low temperature storage of alfalfa leafcutting bee

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The alfalfa leafcutting bee, Megachile rotundata (Hymenoptera: Megachilidae) is a major pollinator in alfalfa seed production systems throughout North America. Recent studies have shown that improved timing of female establishment and alfalfa bloom may allow producers to pollinate alfalfa seed crop...

  13. Comparative Analysis Of 226Ra Soil-To-Plant Transfer In Cabbage Grown In Various Regions

    NASA Astrophysics Data System (ADS)

    Madruga, M. J.; Carvalho, F. P.; Silva, L.; Gouveia, J.

    2008-08-01

    The transfer of 226Ra from soil to cabbage was compared amongst regions, namely the surroundings of Urgeiriça uranium milling tailings (GE), regions with past uranium mining activities (GN1), and regions with no uranium mining activities and no uranium deposits (GN2). Results show a slight increase of the concentration ratio values at low radium concentration in soils. Statistical analysis of the mean 226Ra activity concentrations in soil and cabbage for the three regions was carried out. The comparison of 226Ra activity concentrations in soils indicated no difference (p>0.05), between GE and GN2 and significant differences (p<0.05) between GE and GN1 and between GN1 and GN2. Similar statistical results were obtained for 226Ra activity concentrations in cabbage from the same regions. It was concluded that radium Concentration Ratio (CR) for cabbage grown in the region of the main uranium milling site (GE) is of the same order of magnitude of CR in cabagge grown in background regions (GN2). However, 226Ra CR was higher in cabagge from the region with past uranium mining activities (GN1).

  14. Detection and Quantification of Unbound Phytochelatin 2 in Plant Extracts of Brassica napus Grown with Different Levels of Mercury1

    PubMed Central

    Iglesia-Turiño, Santiago; Febrero, Anna; Jauregui, Olga; Caldelas, Cristina; Araus, Jose Luis; Bort, Jordi

    2006-01-01

    The mercury (Hg) accumulation mechanism was studied in rape (Brassica napus) plants grown under a Hg concentration gradient (0 μm–1,000 μm). Hg mainly accumulated in roots. Therefore, the presence of phytochelatins (PCs) was studied in the roots of the plants. The high stability of the PC-Hg multicomplexes (mPC-nHg) seems to be the main reason for the lack of previous Hg-PC characterization studies. We propose a modification of the method to detect and quantify unbound PC of Hg in plant extracts via high-performance liquid chromatography coupled to electrospray tandem mass spectrometry and inductively coupled plasma mass spectrometry in parallel. We separated the PC from the Hg by adding the chelating agent sodium 2,3-dimercaptopropanesulfonate monohydrate. We only detected the presence of PC after the addition of the chelating agent. Some multicomplexes mPC-nHg could be formed but, due to their large sizes, could not be detected. In this study, only PC2 was observed in plant samples. Hg accumulation was correlated with PC2 concentration (r2 = 0.98). PMID:16920879

  15. An experimental set-up to study carbon, water, and nitrate uptake rates by hydroponically grown plants.

    PubMed

    Andriolo, J L; Le Bot, J; Gary, C; Sappe, G; Orlando, P; Brunel, B; Sarrouy, C

    1996-01-01

    The experimental system described allows concomitant hourly measurements of CO2, H2O, and NO3 uptake rates by plants grown hydroponically in a greenhouse. Plants are enclosed in an airtight chamber through which air flows at a controlled speed. Carbon dioxide exchange and transpiration rates are determined from respective differences of concentrations of CO2 and water vapor of the air at the system inlet and outlet. This set-up is based on the "open-system" principle with improvements made on existing systems. For instance, propeller anemometers are used to monitor air flow rates in the chamber. From their signal it is possible to continuously adjust air speed to changing environmental conditions and plant activity. The air temperature inside the system therefore never rises above that outside. Water and NO3 uptake rates are calculated at time intervals from changes in the volume and the NO3 concentration of the nutrient solution in contact with the roots. The precise measurement of the volume of solution is achieved using a balance which has a higher precision than any liquid level sensors. Nitrate concentration is determined in the laboratory from aliquots of solution sampled at time intervals. A number of test runs are reported which validate the measurements and confirm undisturbed conditions within the system. Results of typical diurnal changes in CO2, H2O, and NO3 uptake rates by fruiting tomato plants are also presented. PMID:11541097

  16. Japanese flowering cherry tree as a woody plant candidate grown in space

    NASA Astrophysics Data System (ADS)

    Tomita-Yokotani, K.; Yoshida, S.; Hashimoto, H.; Nyunoya, H.; Funada, R.; Katayama, T.; Suzuki, T.; Honma, T.; Nagatomo, M.; Nakamura, T.

    We are proposing to raise woody plant in space for several applications Japanese flowering cherry tree is a candidate to do wood science in space Mechanism of sensing gravity and controlling shape of tree has been studied quite extensively Cherry mutants associated with gravity are telling responsible plant hormones and molecular machinery for plant adaptation against action of gravity Space experiment using our wood model contribute to understand molecular and cellular process of gravitropism in plant Tree is considered to be an important member in space agriculture to produce excess oxygen wooden materials for constructing living environment and provide biomass for cultivating mushrooms and insects Furthermore trees and their flowers improve quality of life under stressful environment in outer space

  17. PLUTONIUM-239 AND AMERICIUM-241 UPTAKE BY PLANTS FROM SOIL

    EPA Science Inventory

    Alfalfa was grown in soil contaminated with plutonium-239 dioxide (239PuO2) at a concentration of 29.7 nanocuries per gram (nCi/g). In addition to alfalfa, radishes, wheat, rye, and tomatoes were grown in soils contaminated with americium-241 nitrate (241Am(NO3)3) at a concentrat...

  18. Effect of artificial electric fields on plants grown under microgravity conditions

    NASA Astrophysics Data System (ADS)

    Nechitailo, G.; Gordeev, A.

    2001-01-01

    Ionic and structural hetorogeneity of cells, tissues, and organs of plants are associated with a spectrum of electric characteristics such as bioelectric potentials, electrical conductance, and bioelectric permeability. An important determinant for the plant function is electric properties of the cell membranes and organelles which maintain energy and substance exchange with the environment. Enzymes and other biologically active substances have a powerful charge at the molecular level. Finally, all molecules, including those of water, represent dipoles, and this determines their reactive capacity. A major determinant is the bioelectric polarity of a plant is genetically predetermined and cannot be modified. It is an intrinsic structural feature of the organism whose evolution advent was mediated by gravity. An illustrative presentation of polarity is the downward growth of the roots and upward growth of stems in the Earth's gravitation field. However, gravity is a critical, but not the sole determinant of the plant organism polarization. Potent polarizing effects are exerted by light, the electromagnetic field, moisture, and other factors. It is known that plant cultivation in an upturned position is associated with impairment of water and nutrient uptake, resulting in dyscoordination of physiological processes, growth and developmental retardation. These abnormalities were characteristic when early attempts were made to grow plants in weightlessness conditions.

  19. Phytoremediation efficiency of a pcp-contaminated soil using four plant species as mono- and mixed cultures.

    PubMed

    Hechmi, Nejla; Aissa, Nadhira Ben; Abdenaceur, Hassen; Jedidi, Naceur

    2014-01-01

    Bioremediation of soil polluted by pentachlorophenol (PCP) is of great importance due to the persistence and carcinogenic properties of PCP. Phytoremediation has long been recognized as a promising approach for removal of PCP from soil. The present study was conducted to investigate the capability of four plant species; white clover, ryegrass, alfalfa, and rapeseed grown alone and in combination to remediate pentachlorophenol contaminated soil. After 60 days cultivation, white clover, raygrass, alfalfa, and rapeseed all significantly enhanced the degradation of PCP in soils. Alfalfa showed highest efficiency for the removal of PCP in single cropping flowed by rapeseed and ryegrass. Mixed cropping significantly enhanced the remediation efficiencies as compared to single cropping; about 89.84% of PCP was removed by mixed cropping of rapeseed and alfalfa, and 72.01% of PCP by mixed cropping of rape and white clover. Mixed cropping of rapeseed with alfalfa was however far better for the remediation of soil PCP than single cropping. An evaluation of soil biological activities as a monitoring mechanism for the bioremediation process of a PCP-contaminated soil was made using measurements of microbial counts and dehydrogenase activity. PMID:24933915

  20. Uranium contents in plants and mushrooms grown on a uranium-contaminated site near Ronneburg in Eastern Thuringia/Germany.

    PubMed

    Baumann, Nils; Arnold, Thuro; Haferburg, Götz

    2014-01-01

    Uranium concentrations in cultivated (sunflower, sunchoke, potato) and native plants, plant compartment specimens, and mushrooms, grown on a test site within a uranium-contaminated area in Eastern Thuringia, were analyzed and compared. This test site belongs to the Friedrich-Schiller University Jena and is situated on the ground of a former but now removed uranium mine waste leaching heap. For determination of the U concentrations in the biomaterials, the saps of the samples were squeezed out by using an ultracentrifuge, after that, the uranium concentrations in the saps and the remaining residue were measured, using ICP-MS. The study further showed that uranium concentrations observed in plant compartment and mushroom fruiting bodies sap samples were always higher than their associated solid residue sample. Also, it was found that the detected uranium concentration in the root samples were always higher than were observed in their associated above ground biomass, e.g., in shoots, leaves, blossoms etc. The highest uranium concentration was measured with almost 40 ppb U in a fruiting body of a mushroom and in roots of butterbur. However, the detected uranium concentrations in plants and mushrooms collected in this study were always lower than in the associated surface and soil water of the test site, indicating that under the encountered natural conditions, none of the studied plant and mushroom species turned out to be a hyperaccumulator for uranium, which could have extracted uranium in sufficient amounts out of the uranium-contaminated soil. In addition, it was found that the detected uranium concentrations in the sap samples, despite being above the sensitivity limit, proved to be too low-in combination with the presence of fluorescence quenching substances, e.g., iron and manganese ions, and/or organic quenchers-to extract a useful fluorescence signal, which could have helped to identify the uranium speciation in plants. PMID:23812734

  1. Stress Responses in Alfalfa (Medicago sativa L.) 1

    PubMed Central

    Kessmann, Helmut; Edwards, Robert; Geno, Paul W.; Dixon, Richard A.

    1990-01-01

    The isoflavonoid conjugates medicarpin-3-O-glucoside-6″-O-malonate (MGM), afrormosin-7-O-glucoside (AG), and afrormosin-7-O-glucoside-6″-O-malonate (AGM) were isolated and characterized from cell suspension cultures of alfalfa (Medicago sativa L.), where they were the major constitutive secondary metabolites. They were also found in alfalfa roots but not in other parts of the plant. The phytoalexin medicarpin accumulated rapidly in suspension cultured cells treated with elicitor from Colletotrichum lindemuthianum, and this was subsequently accompanied by an increase in the levels of MGM. In contrast, net accumulation of afrormosin conjugates was not affected by elicitor treatment. Labeling studies with [14C]phenylalanine indicated that afrormosin conjugates were the major de novo synthesized isoflavonoid products in unelicited cells. During elicitation, [14C]phenylalanine was incorporated predominantly into medicarpin, although a significant proportion of the newly synthesized medicarpin was also conjugated. Treatment of 14C-labeled, elicited cells with l-α-aminooxy-β-phenylpropionic acid, a potent inhibitor of PAL activity in vivo, resulted in the initial appearance of labeled medicarpin of very low specific activity, suggesting that the phytoalexin could be released from a preformed conjugate under these conditions. Our data draw attention to the involvement of isoflavone hydroxylases during the constitutive and elicitor-induced accumulation of isoflavonoids and their conjugates in alfalfa cell cultures. PMID:16667691

  2. Microbiological Sampling Methods and Sanitation of Edible Plants Grown on ISS

    NASA Technical Reports Server (NTRS)

    Parrish, Charles H. II; Khodadad, Christina L.; Garland, Nathaniel T.; Larson, Brian D.; Hummreick, Mary E.

    2013-01-01

    Pathogenic microbes on the surfaces of salad crops and growth chambers pose a threat to the health of crew on International Space Station. For astronauts to safely consume spacegrown vegetables produced in NASA's new vegetable production unit, VEGGIE, three technical challenges must be overcome: real-time sampling, microbiological analysis, and sanitation. Raphanus sativus cultivar Cherry Bomb II and Latuca sativa cultivar Outredgeous, two saled crops to be grown in VEGGIE, were inoculated with Salmonella enterica serovar Typhimurium (S. Typhimurium), a bacterium known to cause food-borne illness Tape- and swab-based sampling techniques were optimized for use in microgravity and assessed for effectiveness in recovery of bacteria from crop surfaces: Rapid pathogen detection and molecular analyses were performed via quantitative real-time polymerase chain reactiop using LightCycler® 480 and RAZOR® EX, a scaled-down instrument that is undergoing evaluation and testing for future flight hardware. These methods were compared with conventional, culture-based methods for the recovery of S. Typhimurium colonies. A sterile wipe saturated with a citric acid-based, food-grade sanitizer was applied to two different surface materials used in VEGGIE flight hardware that had been contaminated with the bacterium Pseudomonas aeruginosa,. another known human pathogen. To sanitize surfaces, wipes were saturated with either the sanitizer or sterile deionized water and applied to each surface. Colony forming units of P. aeruginosa grown on tryptic soy agar plates were enumerated from surface samples after sanitization treatments. Depending on the VEGGIE hardware material, 2- to 4.5-log10 reductions in colony-forming units were observed after sanitization. The difference in recovery of S. Typhimurium between tape- and swab- based sampling techniques was insignificant. RAZOR® EX rapidly detected S. Typhimurium present in both raw culture and extracted DNA samples.

  3. The isolation and identification of a light-induced protein in alfalfa sprouts and the cloning of its specific promoter.

    PubMed

    Su, Xin; Xu, Wei-Zhuo; Liu, Xin; Zhuo, Rui-Fang; Wang, Cai-Yun; Zhang, Xin; Kakutani, K; You, Song

    2013-05-15

    We used 2D-PAGE to isolate a light-induced protein (AL-A) that is expressed abundantly in light-growth alfalfa sprouts. The seven amino acids of the N-terminal region of the protein were identified, and we searched for the protein in GenBank using the BLAST program. The results of the homology analysis showed that the amino acid sequence of the isolated protein is most similar to one from a pea plastocyanin. To identify the protein, we amplified and sequenced the DNA fragment encoding AL-A from genomic alfalfa DNA. We found that the AL-A gene was highly homologous (90%) to the sequences from the pea plastocyanin via multiple alignments, and the deduced protein precursor was predicted to be chloroplast-specific via the ChloroP computer program. The protein was named alfalfa-plastocyanin (AL-P). It was characterized as being a light-inducible protein, and RT-PCR analysis showed that AL-P mRNA transcription only occurred in the leaves of the alfalfa plant and the alfalfa seedlings growth in lighted conditions. PCR was also used to amplify the DNA fragment encoding the AL-P promoter (AL-Pp) from genomic alfalfa DNA. PlantCARE analysis of the promoter sequence indicated that both a typical TATA box and a CAAT box were located in the promoter sequence, and some of the cis-elements that are responsible for light responsiveness were also identified within this promoter region. The AL-P gene promoter fused to the β-glucuronidase (GUS) reporter gene has been examined for expression in transgenic alfalfa seedlings. Our findings have a potential application in plant genetic engineering; the AL-Pp may be used to drive the expression of heterologous genes in transgenic alfalfa plants. PMID:23454621

  4. Bioaccumulation of thallium by the wild plants grown in soils of mining area.

    PubMed

    Sasmaz, Merve; Akgul, Bunyamin; Yıldırım, Derya; Sasmaz, Ahmet

    2016-11-01

    Gümüsköy Ag (As, Pb, and Tl) deposits are one of the largest silver deposits in the country and located about 25 km west of Kütahya, Turkey. This study investigated the accumulation and transport of thallium into 11 wild plants in soil of the mining area. Plant samples and their associated soils were collected from the field and Tl contents were measured with inductively coupled plasma mass spectroscopy (ICP-MS). The mean concentrations in the soil, roots, and shoots of the studied plants were, respectively, 170, 318, and 315 mg kg(-1) for Tl. The plants analyzed and collected from the studied area were separated into different groups based on enrichment coefficients of roots and shoots (ECR and ECS). The results showed that because of their higher ECR and ECS, the following could be good bioaccumulators: CY, IS, SL, and VR for Tl. Therefore, these plants can be useful for remediation or phytoremediation of soils polluted by Tl. PMID:27196508

  5. Accumulation and residue of napropamide in alfalfa (Medicago sativa) and soil involved in toxic response.

    PubMed

    Cui, Li E; Yang, Hong

    2011-06-15

    Napropamide belongs to the amide herbicide family and widely used to control weeds in farmland. Intensive use of the herbicide has resulted in widespread contamination to ecosystems. The present study demonstrated an analysis on accumulation of the toxic pesticide napropamide in six genotypes of alfalfa (Medicago sativa), along with biological parameters and its residues in soils. Soil was treated with napropamide at 3 mg kg(-1) dry soil and alfalfa plants were cultured for 10 or 30 d, respectively. The maximum value for napropamide accumulation is 0.426 mg kg(-1) in shoots and 2.444 mg kg(-1) in roots. The napropamide-contaminated soil with alfalfa cultivation had much lower napropamide concentrations than the control (soil without alfalfa cultivation). Also, the content of napropamide residue in the rhizosphere was significantly lower than that in the non-rhizosphere soil. M. sativa exposed to 3 mg kg(-1) napropamide showed inhibited growth. Further analysis revealed that plants treated with napropamide accumulated more reactive oxygen species (O(2)(-) and H(2)O(2)) and less amounts of chlorophyll. However, not all cultivars showed oxidative injury, suggesting that the alfalfa cultivars display different tolerance to napropamide. PMID:21439724

  6. The antenna-specific odorant-binding protein AlinOBP13 of the alfalfa plant bug Adelphocoris lineolatus is expressed specifically in basiconic sensilla and has high binding affinity to terpenoids.

    PubMed

    Sun, L; Xiao, H-J; Gu, S-H; Zhou, J-J; Guo, Y-Y; Liu, Z-W; Zhang, Y-J

    2014-08-01

    Odorant-binding proteins (OBPs) are crucial in the olfactory pathway of insects. In the present study, the antenna-enriched OBP AlinOBP13 was investigated because of its potential contribution to the peripheral olfactory perception in the alfalfa plant bug Adelphocoris lineolatus. The results of quantitative reverse transcriptase-PCR showed that the transcript level of AlinOBP13 was higher in the adult stage than in the nymph stages. The transcript levels of AlinOBP13 in the male and female antennae significantly increased after 4 and 8 h of starvation, respectively. Fine ultrastructures of different types of chemosensilla in both female and male antennae were investigated using transmission electron microscopy and immunocytochemical labelling. The results revealed that the anti-AlinOBP13 antiserum strongly and specifically labelled short basiconic sensilla; this antiserum was restricted to the inner lumen and the cavities below the sensillum base of the sensilla. By contrast, multiporous sensilla trichodea, medium long sensilla basiconica, and aporous sensilla chaetica were not labelled. The present study is the first to report an OBP showing specific expression in the short basiconic sensilla of a member of the Hemipteran species. The results of a fluorescence displacement binding assay indicated that recombinant AlinOBP13 showed a more specific binding preference to terpenoids than to sex pheromones and other classes of chemicals. This binding ability was dramatically affected by pH; higher binding affinities were displayed at pH 10.0 than at pH 7.4 and 5.0. In addition, the results of dose-dependent electroantennogram recordings from the antennae showed that both female and male adult bugs responded to the terpenoids tested, suggesting an apparent physiological relevance of AlinOBP13 in A. lineolatus chemoreception. The results of this study suggest that AlinOBP13 functions as a specific carrier of terpenoids and provide insights into the mechanism of A

  7. Radium-226 and calcium uptake by crops grown in mixtures of sand and cay tailings from phosphate mining

    SciTech Connect

    Million, J.B.; Sartain, J.B.; Gonzalez, R.X.; Carrier, W.D. III

    1994-07-01

    Radium-226 is a naturally occurring radionuclide found in reclaimed clay and sand tailing from phosphate mining. Field studies were conducted to investigate the effects of sand/clay ratio (SCR), Ca supplement and organic amendments on the {sup 226}Ra concentration in turnip, banana pepper, cabbage, yellow squash, mustard, and alfalfa. For vegetables, treatment effects included SCR (2:1, 4:1, 6:1, and 8:1), phosphogypsum (PG) 0,22, and 134 Mg ha{sup {minus}1}, and peat 0,100, and 200 Mg ha{sup {minus}1}. For alfalfa grown in a 1:1 SCR mixture, treatments included organic amendments (control, peat, sewage slude, sawdust, composted sewage sludge, composted garbage and humate) applied at 44.8 Mg ha{sup {minus}1} (2.2 Mg ha{sup {minus}1} for humate). Plant {sup 226}Ra concentration tended to be higher in the 4:1 than in the 2:1 SCR mix but this depended on the crop an d the season. Organic amendments and PG had no effect (p<0.05) on the {sup 226}Ra concentration in vegetables and alfalfa. Mean {sup 226}Ra concentration in plant tissues ranged from 3.4 Bq kg{sup {minus}1} in banana pepper fruit to 31.1 Bq kg{sup {minus}1}. A quadratic relationship based on 631 observations was observed between {sup 226}Ra and Ca concentration in plant tissues. The {sup 226}Ra/Ca ratio in plant tissues ranged from 0.85 to 2.13 kBq {sup 226}Ra kg{sup {minus}1} Ca and decreased with increasing plant {sup 226}Ra. Results indicated that wide differences in plant {sup 226}Ca concentration were related more to differences in plant Ca levels than to soil factors. 21 refs., 1 fig., 6 tabs.

  8. Nitrogen requirements of first-year corn following alfalfa were not altered by fall-applied manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are no published reports on the direct effects of fall manure application on alfalfa (Medicago sativa L.) N credits to first-year corn (Zea mays L.) grown as grain or silage. Therefore, on-farm experiments were conducted at eight locations in Minnesota to test whether manure applied during fal...

  9. Effects of elevated carbon dioxide on photosynthesis and productivity of alfalfa in relation to seasonal changes in temperature

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa was grown at ambient and elevated (ambient + 350 ppm) carbon dioxide concentrations at Beltsville, Maryland, using open top chambers in field plots. Periodic harvests and measurements of leaf photosynthesis were used to test the hypothesis that the stimulation of yield and photosynthesis by...

  10. Root-shoot interactions explain the reduction of leaf mineral content in Arabidopsis plants grown under elevated [CO2 ] conditions.

    PubMed

    Jauregui, Ivan; Aparicio-Tejo, Pedro M; Avila, Concepción; Cañas, Rafael; Sakalauskiene, Sandra; Aranjuelo, Iker

    2016-09-01

    Although shoot N depletion in plants exposed to elevated [CO2 ] has already been reported on several occasions, some uncertainty remains about the mechanisms involved. This study illustrates (1) the importance of characterizing root-shoot interactions and (2) the physiological, biochemical and gene expression mechanisms adopted by nitrate-fed Arabidopsis thaliana plants grown under elevated [CO2 ]. Elevated [CO2 ] increases biomass and photosynthetic rates; nevertheless, the decline in total soluble protein, Rubisco and leaf N concentrations revealed a general decrease in leaf N availability. A transcriptomic approach (conducted at the root and shoot level) revealed that exposure to 800 ppm [CO2 ] induced the expression of genes involved in the transport of nitrate and mineral elements. Leaf N and mineral status revealed that N assimilation into proteins was constrained under elevated [CO2 ]. Moreover, this study also highlights how elevated [CO2 ] induced the reorganization of nitrate assimilation between tissues; root nitrogen assimilation was favored over leaf assimilation to offset the decline in nitrogen metabolism in the leaves of plants exposed to elevated [CO2 ]. PMID:26801348

  11. Transcriptome profiling in Arabidopsis inflorescence stems grown under hypergravity in terms of cell walls and plant hormones

    NASA Astrophysics Data System (ADS)

    Tamaoki, D.; Karahara, I.; Nishiuchi, T.; De Oliveira, S.; Schreiber, L.; Wakasugi, T.; Yamada, K.; Yamaguchi, K.; Kamisaka, S.

    2009-07-01

    Land plants rely on lignified secondary cell walls in supporting their body weight on the Earth. Although gravity influences the formation of the secondary cell walls, the regulatory mechanism of their formation by gravity is not yet understood. We carried out a comprehensive analysis of gene expression in inflorescence stems of Arabidopsis thaliana L. using microarray (22 K) to identify genes whose expression is modulated under hypergravity condition (300 g). Total RNA was isolated from the basal region of inflorescence stems of plants grown for 24 h at 300 g or 1 g. Microarray analysis showed that hypergravity up-regulated the expression of 403 genes to more than 2-fold. Hypergravity up-regulated the genes responsible for the biosynthesis or modification of cell wall components such as lignin, xyloglucan, pectin and structural proteins. In addition, hypergravity altered the expression of genes related to the biosynthesis of plant hormones such as auxin and ethylene and that of genes encoding hormone-responsive proteins. Our transcriptome profiling indicates that hypergravity influences the formation of secondary cell walls by modulating the pattern of gene expression, and that auxin and/or ethylene play an important role in signaling hypergravity stimulus.

  12. Processed Whole Pine Trees as a Substrate for Container-grown Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies were conducted at the Southern Horticultural Laboratory in Poplarville, MS. Six to eight inch diameter loblolly pine (Pinus taeda L.) were harvested from a 10 year old planted pine plantation in south Mississippi. The entire tree including needles was feed through a drum chipper. Resulting...

  13. Transgene expression for Gladiolus plants grown outdoors and in the greenhouse

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Transgene expression was evaluated for Gladiolus plants transformed with either the CaMV 35S, double CaMV 35S, rolD, or Arabidopsis UBQ3 promoter controlling the uidA or bean yellow mosaic virus coat protein gene in either the sense or antisense orientation to determine differences in expression for...

  14. Fall-grown oat forages: cultivars, planting dates, and expected yields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For the dairy industry, the options for producing a late-summer emergency forage crop are limited, mostly because the growing season is relatively short. Recent work conducted at Prairie du Sac (WI) has demonstrated that some cereal grains (primarily oats) planted in early August will joint, elongat...

  15. Effect of Nitrogen Availability on Mineral Nutrient Uptake and Plant Growth of Container-Grown Hydrangeas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rooted liners of Hydrangea macrophylla 'Red Star' were fertigated with one of three nitrogen (N) concentrations (0, 140, or 280 ppm) in a modified Hoagland’s solution from June to November. Every 3 weeks starting in June, plants in each N treatment (0N, 140N, 280N) were destructively harvested to de...

  16. Effect of Hypergravity on Localization Calcium Ions in Plant Cells Grown in Vivo and in Vitro

    NASA Astrophysics Data System (ADS)

    Nedukha, Olena

    Using plant callus tissues and Arabidopsis thaliana plants as model systems we have been investigated the effect of hypergravity on the localization and relative content of calcium ions in photosynthesizing cells. The tobacco callus cells in log stage of growth and mesophyll cells from developed A. thaliana leaves were used in the experiments. Plant samples were exposed to hypergravity at 6.5 g, 10g and 14 g for 15-60 min. After centrifugation, dye Fluo-4 was loaded in the control leaves and the centrifuged samples by the standard cytochemical method. Observation of calcium fluorescence was carried out with a laser confocal microscope LSM 5 Pascal at the excitation wave 488 nm (by the argon laser), at emission wavelength 516 nm. The data of the calcium ion distribution and quantification in cells were obtained using software "Pascal" (Carl Zeiss). The effect of hypergravity on redistribution of calcium ions in plant cells has been established. This effect is depended from exposure time and from the value of hypergravity. The cells cultivated in vitro is showed fast response to hypergravity influence. Plasmolysis cells and calcium domains formation have been observed in most of callus cells. This influence was like to that, which was wrote in Funaria hygrometrica protonema cells after 8.5 g influence (Sytnik et al., 1984). Leaf cells of A. thaliana were of less responsively to hypergravity than callus cells. Sytnik K, Kordyum E, Nedukha O. et al. 1984. Plant Cell Under Change of Geophysical Factors. Kiev: Naukova Dumka, 1-134 p.

  17. Analysis of Leaf and Root Transcriptome of Soil Grown Avena barbata Plants

    SciTech Connect

    Swarbreck, Sté; phanie,; Lindquist, Erika; Ackerly, David; Andersen, Gary

    2011-02-01

    Slender wild oat (Avena barbata) is an annual grass dominant in many grassland ecosystems in Mediterranean climate. This species has been the subject of ecological studies that aim at understanding the effect of global climate change on grassland ecosystems and the genetic basis for adaptation under varying environmental conditions. We present the sequencing and analysis of cDNA libraries constructed from leaf and root samples collected from A. barbata grown on natural soil and under varying rainfall patterns. More than one million expressed sequence tags (ESTs) were generated using both GS 454-FLX pyrosequencing and Sanger sequencing, and these tags were assembled into consensus sequences. We identified numerous candidate polymorphic markers in the dataset, providing possibilities for linking the genomic and the existing genetic information for A. barbata. Using the digital northern method, we showed that genes involved in photosynthesis were down regulated under high rainfall while stress- related genes were up regulated. We also identified a number of genes unique to the root library with unknown function. Real-time RT-PCR was used to confirm the root specificity of some of these transcripts such as two genes encoding O-methyl transferase. Also we showed differential expression under three water levels. Through a combination of Sanger and 454-based sequencing technologies, we were able to generate a large set of transcribed sequences for A. barbata. This dataset provides a platform for further studies of this important wild grass species

  18. Use of the physiologically-based extraction test to assess the oral bioaccessibility of metals in vegetable plants grown in contaminated soil.

    PubMed

    Intawongse, Marisa; Dean, John R

    2008-03-01

    The oral bioaccessibility of metals in vegetable plants grown on contaminated soil was assessed. This was done using the physiologically-based extraction test (PBET) to simulate the human digestion of plant material. A range of vegetable plants, i.e. carrot, lettuce, radish and spinach, were grown on metal contaminated soil. After reaching maturity the plants were harvested and analysed for their total metal content (i.e. Cr, Cd, Cu, Fe, Mn, Mo, Ni, Pb and Zn) by inductively coupled plasma-mass spectrometry (ICP-MS). The plant samples were then subsequently extracted using an in vitro gastrointestinal approach or PBET to assess the likelihood of oral bioaccessibility if the material was consumed by humans. PMID:17601641

  19. Phyto extraction and accumulation of mercury in selected plant species grown in soil contaminated with different mercury compounds

    SciTech Connect

    Su, Y.; Han, F.; Shiyab, S.; Monts, D.L.

    2007-07-01

    /kg). Consequently, this plant species may not be suitable for mercury phyto-remediation. Other plant species, such as Indian mustard (Brassica juncea), a well-studied metal accumulator, exhibited severe chlorosis symptoms during some experiments. Among all the plant species studied, Chinese brake fern (Pteris vittata) accumulated significant amount of mercury in both roots and shoots and hence may be considered as a potential candidate for mercury phyto-extraction. During one experiment, brake ferns accumulated 540 mg/kg and 1469 mg/kg in shoots after 18 days of growing in soils treated with 500 ppm and 1000 ppm HgCl{sub 2} powder, respectively; no visual stress symptoms were observed. We also studied mercury phyto-remediation using aged soils that contaminated HgS, HgCl{sub 2}, and Hg(NO{sub 3}){sub 2}. We have found that up to hundreds of ppm mercury can be accumulated in the roots of Indian mustard plants grown with soil contaminated by mercury sulfide; HgS is assumed to be the most stable and also the predominant mercury form in Oak Ridge flood plain soils. We have also started to investigate different mercury uptake mechanisms, such as root uptake of soil contaminant and foliar mercury accumulation from ambient air. (authors)

  20. Overexpression of malate dehydrogenase in transgenic alfalfa enhances organic acid synthesis and confers tolerance to aluminum.

    PubMed

    Tesfaye, M; Temple, S J; Allan, D L; Vance, C P; Samac, D A

    2001-12-01

    Al toxicity is a severe impediment to production of many crops in acid soil. Toxicity can be reduced through lime application to raise soil pH, however this amendment does not remedy subsoil acidity, and liming may not always be practical or cost-effective. Addition of organic acids to plant nutrient solutions alleviates phytotoxic Al effects, presumably by chelating Al and rendering it less toxic. In an effort to increase organic acid secretion and thereby enhance Al tolerance in alfalfa (Medicago sativa), we produced transgenic plants using nodule-enhanced forms of malate dehydrogenase and phosphoenolpyruvate carboxylase cDNAs under the control of the constitutive cauliflower mosaic virus 35S promoter. We report that a 1.6-fold increase in malate dehydrogenase enzyme specific activity in root tips of selected transgenic alfalfa led to a 4.2-fold increase in root concentration as well as a 7.1-fold increase in root exudation of citrate, oxalate, malate, succinate, and acetate compared with untransformed control alfalfa plants. Overexpression of phosphoenolpyruvate carboxylase enzyme specific activity in transgenic alfalfa did not result in increased root exudation of organic acids. The degree of Al tolerance by transformed plants in hydroponic solutions and in naturally acid soil corresponded with their patterns of organic acid exudation and supports the concept that enhancing organic acid synthesis in plants may be an effective strategy to cope with soil acidity and Al toxicity. PMID:11743127

  1. Transcriptome Analysis of Resistant and Susceptible Alfalfa Cultivars Infected With Root-Knot Nematode Meloidogyne incognita

    PubMed Central

    Postnikova, Olga A.; Hult, Maria; Shao, Jonathan; Skantar, Andrea; Nemchinov, Lev G.

    2015-01-01

    Nematodes are one of the major limiting factors in alfalfa production. Root-knot nematodes (RKN, Meloidogyne spp.) are widely distributed and economically important sedentary endoparasites of agricultural crops and they may inflict significant damage to alfalfa fields. As of today, no studies have been published on global gene expression profiling in alfalfa infected with RKN or any other plant parasitic nematode. Very little information is available about molecular mechanisms that contribute to pathogenesis and defense responses in alfalfa against these pests and specifically against RKN. In this work, we performed root transcriptome analysis of resistant (cv. Moapa 69) and susceptible (cv. Lahontan) alfalfa cultivars infected with RKN Meloidogyne incognita, widespread root-knot nematode species and a major pest worldwide. A total of 1,701,622,580 pair-end reads were generated on an Illumina Hi-Seq 2000 platform from the roots of both cultivars and assembled into 45,595 and 47,590 transcripts in cvs Moapa 69 and Lahontan, respectively. Bioinformatic analysis revealed a number of common and unique genes that were differentially expressed in susceptible and resistant lines as a result of nematode infection. Although the susceptible cultivar showed a more pronounced defense response to the infection, feeding sites were successfully established in its roots. Characteristically, basal gene expression levels under normal conditions differed between the two cultivars as well, which may confer advantage to one of the genotypes toward resistance to nematodes. Differentially expressed genes were subsequently assigned to known Gene Ontology categories to predict their functional roles and associated biological processes. Real-time PCR validated expression changes in genes arbitrarily selected for experimental confirmation. Candidate genes that contribute to protection against M. incognita in alfalfa were proposed and alfalfa-nematode interactions with respect to resistance

  2. Effects of cadmium on cork oak (Quercus suber L.) plants grown in hydroponics.

    PubMed

    Gogorcena, Yolanda; Larbi, Ajmi; Andaluz, Sofia; Carpena, Ramón O; Abadía, Anunciación; Abadía, Javier

    2011-12-01

    Cork oak (Quercus suber L.) is an autochthonous tree species that is being used for reforestation in heavy-metal-contaminated areas in Spain. A hydroponics experiment was carried out to characterize the effects of Cd on several morphological and physiological parameters in this species, including shoot length, nutrient concentrations and allocation in different organs, leaf pigment concentrations, photosynthetic efficiency, root ferric chelate reductase (FCR) activity and organic acid concentrations in xylem sap. Four different Cd treatments were applied, adding Cd chelated with EDTA or as chloride salt at two different concentrations (10 and 50 µM Cd). After 1 month of Cd treatment, plant growth was significantly inhibited in all treatments. Results indicate that Cd accumulates in all organs 7- to 500-fold when compared with control plants. The highest Cd concentration was found in the 50 µM CdCl(2) treatment, which led to concentrations of ~30, 123 and 1153 µg Cd g(-1) dry weight in leaves, stems and roots, respectively. In the strongest Cd treatments the concentrations of P and Ca decreased in some plant parts, whereas the Mn leaf concentrations decreased with three of the four Cd treatments applied. The concentrations of chlorophyll and carotenoids on an area basis decreased, whereas the (zeaxanthin plus antheraxanthin)/(total violaxanthin cycle carotenoids) ratio and the non-photochemical quenching increased significantly in all Cd treatments. Cadmium treatments caused significant increases in the activity of the enzyme FCR in roots and in the concentrations of organic acids in xylem sap. Some of the physiological changes found support the fact that Cd induces a deficiency of Fe in cork oak, although the plant Fe concentrations were not reduced significantly. At higher concentrations the effects of Cd were more pronounced, and were more marked when Cd was in the free ion form than when present in the form of Cd-EDTA. PMID:22121153

  3. [Analysis of Symbiotic Genes of Leguminous Plants Nodule Bacteria Grown in the Southern Urals].

    PubMed

    Baymiev, An Kh; Ivanova, E S; Gumenko, R S; Chubukova, O V; Baymiev, Al Kh

    2015-12-01

    Bacterial strains isolated from the nodules, tissues, and root surface of wild legumes growing in the Southern Urals related to the tribes Galegeae, Hedysareae, Genisteae, Trifolieae, and Loteae were examined for the presence in their genomes of symbiotic (sym) genes. It was found that the sym-genes are present in microorganisms isolated only from the nodules of the analyzed plants (sym+ -strains). Phylogenetic analysis of sym+ -strains on the basis of a comparative analysis of 16S rRNA gene sequences showed that sym+ -strains belong to five families of nodule bacteria: Mesorhizobium, Bradyrhizobium, Sinorhizobium, Rhizobium, and Phyllobacterium. A study the phylogeny of the sym-genes showed that the nodule bacteria of leguminous plants of the Southern Urals at the genus level are mainly characterized by a parallel evolution of symbiotic genes and the 16S rRNA gene. Thus, cases of horizontal transfer of sym genes, which sometimes leads to the formation of certain types of atypical rhizobial strains ofleguminous plants, are detected in nodule bacteria populations. PMID:27055295

  4. Bioaccumulation of heavy metals in crop plants grown near Almeda Textile Factory, Adwa, Ethiopia.

    PubMed

    Gitet, Hintsa; Hilawie, Masho; Muuz, Mehari; Weldegebriel, Yirgaalem; Gebremichael, Dawit; Gebremedhin, Desta

    2016-09-01

    The contents of heavy metals cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) present in water (wastewater and wetland), soils, and food crops collected from the vicinity of Almeda Textile Factory were quantified using Flame Atomic Absorption Spectrometer (FAAS) in order to assess the environmental impact of the textile factory. The contents of heavy metals determined in the wastewater were found below the recommended limit set by WHO and United States Environmental Protection Agency (US EPA) except for Cr, which was found slightly higher than WHO permissible limit. Besides, the contents of the heavy metals determined in soils were below the permissible level of FAO/WHO and Canada maximum allowable limits. Moreover, only the concentrations of Cd and Pb were found above the permissible level set by FAO/WHO in the crop plants studied. Generally, the mean concentrations of heavy metals in the plants were in the decreasing order of: Mn > Zn > Cu > Pb > Ni > Co > Cr > Cd. Nevertheless, higher bioconcentration factor (BCF) was found for Cd (0.108-1.156) followed by Zn (0.081-0.499). In conclusion, comparison of heavy metal concentrations with the permissible limits in all collected sample types i.e. water, soil, and crop plants did not show significant pollution from the factory. PMID:27485616

  5. Species and tissue type regulate long-term decomposition of brackish marsh plants grown under elevated CO2 conditions

    NASA Astrophysics Data System (ADS)

    Jones, Joshua A.; Cherry, Julia A.; McKee, Karen L.

    2016-02-01

    Organic matter accumulation, the net effect of plant production and decomposition, contributes to vertical soil accretion in coastal wetlands, thereby playing a key role in whether they keep pace with sea-level rise. Any factor that affects decomposition may affect wetland accretion, including atmospheric CO2 concentrations. Higher CO2 can influence decomposition rates by altering plant tissue chemistry or by causing shifts in plant species composition or biomass partitioning. A combined greenhouse-field experiment examined how elevated CO2 affected plant tissue chemistry and subsequent decomposition of above- and belowground tissues of two common brackish marsh species, Schoenoplectus americanus (C3) and Spartina patens (C4). Both species were grown in monoculture and in mixture under ambient (350-385 μL L-1) or elevated (ambient + 300 μL L-1) atmospheric CO2 conditions, with all other growth conditions held constant, for one growing season. Above- and belowground tissues produced under these treatments were decomposed under ambient field conditions in a brackish marsh in the Mississippi River Delta, USA. Elevated CO2 significantly reduced nitrogen content of S. americanus, but not sufficiently to affect subsequent decomposition. Instead, long-term decomposition (percent mass remaining after 280 d) was controlled by species composition and tissue type. Shoots of S. patens had more mass remaining (41 ± 2%) than those of S. americanus (12 ± 2%). Belowground material decomposed more slowly than that placed aboveground (62 ± 1% vs. 23 ± 3% mass remaining), but rates belowground did not differ between species. Increases in atmospheric CO2 concentration will likely have a greater effect on overall decomposition in this brackish marsh community through shifts in species dominance or biomass allocation than through effects on tissue chemistry. Consequent changes in organic matter accumulation may alter marsh capacity to accommodate sea-level rise through vertical

  6. A comparison of constitutive promoters for expression of transgenes in alfalfa (Medicago sativa).

    PubMed

    Samac, Deborah A; Tesfaye, Mesfin; Dornbusch, Melinda; Saruul, Purev; Temple, Stephen J

    2004-08-01

    The activity of constitutive promoters was compared in transgenic alfalfa plants using two marker genes. Three promoters, the 35S promoter from cauliflower mosaic virus (CaMV), the cassava vein mosaic virus (CsVMV) promoter, and the sugarcane bacilliform badnavirus (ScBV) promoter were each fused to the beta-glucuronidase (gusA) gene. The highest GUS enzyme activity was obtained using the CsVMV promoter and all alfalfa cells assayed by in situ staining had high levels of enzyme activity. The 35S promoter was expressed in leaves, roots, and stems at moderate levels, but the promoter was not active in stem pith cells, root cortical cells, or in the symbiotic zones of nodules. The ScBV promoter was active primarily in vascular tissues throughout the plant. In leaves, GUS activity driven by the CsVMV promoter was approximately 24-fold greater than the activity from the 35S promoter and 38-fold greater than the activity from the ScBV promoter. Five promoters, the double 35S promoter, figwort mosaic virus (FMV) promoter, CsVMV promoter, ScBV promoter, and alfalfa small subunit Rubisco (RbcS) promoter were used to control expression of a cDNA from Trichoderma atroviride encoding an endochitinase (ech42). Highest chitinase activity in leaves, roots, and root nodules was obtained in plants containing the CsVMV:ech42 transgene. Plants expressing the endochitinase were challenged with Phoma medicaginis var. medicaginis, the causal agent of spring black stem and leaf spot of alfalfa. Although endochitinase activity in leaves of transgenic plants was 50- to 2650-fold greater than activity in control plants, none of the transgenic plants showed a consistent increase in disease resistance compared to controls. The high constitutive levels of both GUS and endochitinase activity obtained demonstrate that the CsVMV promoter is useful for high-level transgene expression in alfalfa. PMID:15517994

  7. Alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Legumes, with more than 650 genera and 20,000 species, range from herbaceous annuals to woody perennials that are important for providing quality human diet and livestock diet. Legumes also contribute to sustainable agriculture because they can fix nitrogen in symbiosis with the soil bacteria called...

  8. Alfalfa

    MedlinePlus

    ... like estrogen, and this might affect the pregnancy. “Auto-immune diseases” such as multiple sclerosis (MS), lupus ( ... active, and this could increase the symptoms of auto-immune diseases. There are two case reports of ...

  9. EFFECT OF AN OZONE INJURY RETARDANT CHEMICAL ON ISOZYME PROFILES FROM ALFALFA CALLUS IN VITRO

    EPA Science Inventory

    Plant ozone injury retardant (EDU or ethylenediurea) at 1.0 ppm inhibited growth of callus of alfalfa cultivars Williamsburg (ozone-sensitive) and MSB-CW5An2(ozone-insensitive) germplasm of Medicago sative. The presence of EDU(0.1 ppm) in growth medium increased the number of pro...

  10. Impact of growth environment variability on alfalfa yield, cellulosic ethanol traits, and paper pulp characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is a promising bioenergy feedstock due to its high yield, nitrogen-fixation capacity, high net energy ratio, potential for planting in rotation with corn, and valuable protein co-product (leaf meal). Our objective was to examine the effect of growth environment on biomass yield, cellulosic e...

  11. Emergence, forage production, and ion relations of alfalfa in response to saline waters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L) is an important crop utilized in regions under irrigation commonly impacted by salinity. In this study we evaluate the effect of salinity, as a continual process, from emergence to mature plant growth in successive harvests. We studied emergence, biomass production, salt ...

  12. TANNIN-CONTAINING ALFALFA: A WAY TO IMPROVE NITROGEN-USE AND PROFITABILITY OF DAIRY FARMS?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Binding of condensed tannins to protein can prevent excessive proteolysis in forages during ensiling, ruminal digestion, and decay of residues in soil. Plant breeding and biotechnology efforts are underway in the U.S. and abroad to develop alfalfa and other forages with adequate levels of tannin for...

  13. The Impact of Distinct Insect Species on Pollination and Gene Flow in Alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pollinator species and plant density can influence pollination and gene flow. The efficacy of different floral visitors at tripping alfalfa flowers was examined in both low and high density patches to determine their potential role in pollination. In addition, for a subset of the floral visitors, th...

  14. Forage Quality of Biomass vs. Conventional Alfalfa Cut at Early Bud or Late Flower Maturity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cellulosic bioenergy systems will result in large areas planted to biomass crops. An important question is whether biomass crops can also be used for livestock feed. This study compared forage quality of an experimental alfalfa germplasm developed for a biomass production system with a conventional ...

  15. Variation Due to Growth Environment in Alfalfa Yield, Cellulosic Ethanol Traits, and Paper Pulp Characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L.) is a promising bioenergy and bioproduct feedstock because of its high yield, N-fixation capacity, potential for planting in rotation with corn (Zea mays L.), and valuable protein co-product (leaf meal). Our objective was to examine the effect of growth environment on bio...

  16. Pythium and Fusarium species causing seed rot and damping-off of alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed rot and damping-off is an important disease of alfalfa, severely affecting stand establishment when conditions favor the disease. This disease may have been overlooked as a cause of poor stand establishment and reduced vigor of adult plants. Globally, 15 Pythium species have been found to cause...

  17. 76 FR 5780 - Determination of Regulated Status of Alfalfa Genetically Engineered for Tolerance to the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-02

    ...This notice advises the public of the Animal and Plant Health Inspection Service's (APHIS) record of decision and determination on the petition regarding the regulated status of alfalfa genetically engineered for tolerance to the herbicide glyphosate based on APHIS' final environmental impact...

  18. Role of curli and plant cultivation conditions on Escherichia coli O157:H7 internalization into spinach grown on hydroponics and in soil.

    PubMed

    Macarisin, Dumitru; Patel, Jitendra; Sharma, Vijay K

    2014-03-01

    Contamination of fresh produce could represent a public health concern because no terminal kill step is applied during harvest or at the processing facility to kill pathogens. In addition, once contaminated, pathogens may internalize into produce and be protected from disinfectants during the postharvest processing step. The objective of the current study was to determine the potential internalization of Escherichia coli O157:H7 into spinach roots and subsequent transfer to the edible parts. Because curli are involved in biofilm formation, we investigated whether their presence influence the internalization of E. coli O157:H7 into spinach. Further, the effect of the spinach cultivar on E. coli O157:H7 internalization was evaluated. Spinach plants were grown in contaminated soil as well as hydroponically to prevent mechanical wounding of the roots and inadvertent transfer of pathogens from the contamination source to the non-exposed plant surfaces. Results showed that E. coli O157:H7 could internalize into hydroponically grown intact spinach plants through the root system and move to the stem and leaf level. The incidence of internalization was significantly higher in hydroponically grown plants when roots were exposed to 7 log CFU/mL compared to those exposed to 5 log CFU/mL. The effect of cultivar on E. coli O157:H7 internalization was not significant (P>0.05) for the analyzed spinach varieties, internalization incidences showing almost equal distribution between Space and Waitiki, 49.06% and 50.94% respectively. Wounding of the root system in hydroponically grown spinach increased the incidence of E. coli O157:H7 internalization and translocation to the edible portions of the plant. Experimental contamination of the plants grown in soil resulted in a greater number of internalization events then in those grown hydroponically, suggesting that E. coli O157:H7 internalization is dependent on root damage, which is more likely to occur when plants are grown in soil

  19. Macroelemental composition of cadmium stressed lettuce plants grown under conditions of intensive sulphur nutrition.

    PubMed

    Matraszek, Renata; Hawrylak-Nowak, Barbara; Chwil, Stanisław; Chwil, Mirosława

    2016-09-15

    Lettuce (Lactuca sativa L.) is moderately sensitive to cadmium (Cd) and shows high accumulation of this metal. Thus, this species is considered to be a good model for both identifying determinants controlling Cd accumulation in plant tissues and for developing breeding strategies aimed at limiting the accumulation of this metal in edible tissues. Simultaneously, lettuce is characterised by medium requirements for sulphur (S) - a macronutrient whose role is associated not only with proper growth and development, but also with stress tolerance. The common use of NPK fertilizers without sulphates (S-SO4) together with the progressive process of reducing emissions of S compounds to the natural environment may lead to deficiency of this element in plants. The present study evaluated the changes in macronutrient content and accumulation in Cd-stressed lettuce 'Justyna' supplied with different S doses. Four concentrations of Cd (0, 0.0002, 0.02 or 0.04 mM) and three levels of S applied in the form of S-SO4 (2, 6 or 9 mM S) were used. Cd exposure impaired the macronutrient balance and accumulation in lettuce. Intensive S nutrition to some extent alleviated Cd-induced toxicity. High S doses, especially 6 mM S, partially improved macronutrient status and restored the macronutrient balance. In Cd-stressed plants supplemented with additional S, an increase in root and shoot biomass and in the content of N, K and Mg was found, without significant changes in the Ca content. Simultaneously, the P and S contents in the biomass of both above- and underground organs remained unchanged. In the leaves, as opposite to the roots, intensive S nutrition reduced the accumulation of Cd. However, the foliar Cd concentration still exceeded the acceptable limits established for consumption. All the obtained results concerning the content of macronutrients and their ratios were referred, inter alia, to the standards i.e. the Diagnosis and Recommendation Integrated System (DRIS) norms. PMID

  20. Phytoremediation potential of Cd and Zn by wetland plants, Colocasia esculenta L. Schott., Cyperus malaccensis Lam. and Typha angustifolia L. grown in hydroponics.

    PubMed

    Chayapan, P; Kruatrachue, M; Meetam, M; Pokethitiyook, P

    2015-09-01

    Cadmium and zinc phytoremediation potential of wetland plants, Colocasia esculenta, Cyperus malaccensis, and Typha angustifolia, was investigated. Plants were grown for 15 days in nutrient solutions containing various concentrations of Cd (0, 5, 10, 20, 50 mg l(-1)) and Zn (0, 10, 20, 50, 100 mg l(-1)). T angustifolia was tolerant to both metals as indicated by high RGR when grown in 50 mg I(-1) Cd and 100 mg I(-1) Zn solutions. All these plants accumulated more metals in their underground parts and > 100 mg kg(-1) in their aboveground with TF values < 1. Only C. esculenta could be considered a Zn hyperaccumulator because it could concentrate > 10,000 mg kg(-1) in its aboveground parts with TF > 1. T angustifolia exhibited highest biomass production and highest Cd and Zn uptake, confirming that this plant is a suitable candidate for treating of Cd contaminated soil/sediments. PMID:26521563

  1. Natural control of corn postharvest fungi Aspergillus flavus and Penicillium sp. using essential oils from plants grown in Argentina.

    PubMed

    Camiletti, Boris X; Asensio, Claudia M; Pecci, María de la Paz Giménez; Lucini, Enrique I

    2014-12-01

    The objective in this study was to evaluate the antifungal activity of essential oils from native and commercial aromatic plants grown in Argentina against corn postharvest fungi and to link the essential oil bioactivity with lipid oxidation and morphological changes in fungus cell membrane. Essential oil (EO) of oregano variety Mendocino (OMen), Cordobes (OCor), and Compacto (OCom), mint variety Inglesa (Mi), and Pehaujo (Mp), Suico (Sui); rosemary (Ro), and Aguaribay (Ag) were tested in vitro against 4 corn fungi: A. flavus (CCC116-83 and BXC01), P. oxalicum (083296), and P. minioluteum (BXC03). The minimum fungicidal concentration (MFC) and the minimum inhibitory concentration (MIC) were determined. The chemical profiles of the EOs were analyzed by GC-MS. Lipid oxidation in cell membrane of fungi was determined by hydroperoxides and related with essential oil antifungal activity. The major compounds were Thymol in OCor (18.66%), Omen (12.18%), and OCom (9.44%); menthol in Mi and Mp; verbenone in Sui; dehydroxy-isocalamendiol in Ag; and eucaliptol in Ro. OCor, Omen, and OCom showed the best antifungal activity. No antifungal activity was observed in Ag and Ro EO. The hydroperoxide value depended on the fungi (P < 0.001) and the antimicrobial agent (P < 0.001).Membrane lipids were oxidized by Sui EO in A. flavus BXC01 and A. flavus CCC116-83 (0.021 and 0.027 meqO2 /kg, respectively). The results suggest that the EOs of OCor, OMen, OCom, Mi, Mp, and Sui grown in Argentina can be used as natural alternatives to control fungi that produce mycotoxin in maize. PMID:25376651

  2. Effect of replacing alfalfa with panicled-tick clover or sericea lespedeza in corn-alfalfa-based substrates on in vitro ruminal methane production.

    PubMed

    Naumann, H D; Lambert, B D; Armstrong, S A; Fonseca, M A; Tedeschi, L O; Muir, J P; Ellersieck, M R

    2015-06-01

    Methane emissions from ruminant livestock contribute to total anthropogenic greenhouse gas emissions and reduce metabolizable energy intake by the animal. Condensed tannins (CT) are polyphenolic plant secondary compounds commonly produced by some perennial forage legumes that characteristically bind to protein, carbohydrates, and minerals. The degree to which CT may affect ruminant nutrition depends upon the concentration, structural composition, and biological activity of the CT. The objective of our experiment was to determine the effect of replacing alfalfa in a corn-alfalfa-based substrate with a legume containing CT on in vitro CH4 production and the dynamics of fermentation using an in vitro gas production technique. All fermented substrates contained 50% ground corn as the energy concentrate portion, whereas the forage portion (50%) of each diet was comprised of alfalfa (control) or some combination of alfalfa and sericea lespedeza (SL) or panicled-tick clover (PTC). Our treatments consisted of PTC or SL 15, 30, and 45, which corresponded with 15, 30, or 45% replacement of the diet (alfalfa component) with either PTC or SL. Substrates containing 45% PTC or SL reduced in vitro CH4 production. Treatments did not affect total gas production as compared with that of the control. Replacement of alfalfa with SL or PTC increased fermentable organic matter (FOM). The PTC treatment increased FOM by as much as 1.8% at the 45% replacement level, whereas FOM of SL 45 was increased by less than 1%. The replacement of alfalfa with PTC increased substrate nutritive value greater than replacement with SL. There were no correlations between any physicochemical constituent of the substrates and CH4 production. A combination of factors associated with the inclusion of PTC and SL contributed to the in vitro CH4 production, and CT in these forages was likely a major contributing factor. Further confirmation of these results on in situ or in vivo animal systems is required. If

  3. Constitutive Overexpression of Cytosolic Glutamine Synthetase (GS1) Gene in Transgenic Alfalfa Demonstrates That GS1 May Be Regulated at the Level of RNA Stability and Protein Turnover1

    PubMed Central

    Ortega, Jose Luis; Temple, Stephen J.; Sengupta-Gopalan, Champa

    2001-01-01

    Glutamine synthetase (GS) catalyzes the ATP-dependent condensation of NH4+ with glutanate to yield glutamine. Gene constructs consisting of the cauliflower mosaic virus (CaMV) 35S promoter driving a cytosolic isoform of GS (GS1) gene have been introduced into alfalfa (Medicago sativa). Although transcripts for the transgene were shown to accumulate to high levels in the leaves, they were undetectable in the nodules. However, significant amounts of β-glucuronidase activity could be detected in nodules of plants containing the CaMV 35S promoter-β-glucuronidase gene construct, suggesting that the transcript for the GS1 transgene is not stable in the root nodules. Leaves of alfalfa plants with the CaMV 35S promoter-GS1 gene showed high levels of accumulation of the transcript for the transgene when grown under low-nitrogen conditions and showed a significant drop in the level of GS1 transcripts when fed with high levels of NO3−. However, no increase in GS activity or polypeptide level was detected in the leaves of transgenic plants. The results suggest that GS1 is regulated at the level of RNA stability and protein turnover. PMID:11351075

  4. Elemental concentration of a native fern from Greece that grows in a monoculture and of corn plants grown in the same soil with different levels of copper

    SciTech Connect

    Procopiou, J.; Wallace, A.

    1982-07-01

    Analysis of a native fern (Pteridium aquilinum L.) growing in large tracts of soil at about 1200 meters mean sea level in Greece indicated that it tolerated low levels of copper. Corn plants (Zea mays L.) grown in potted soil from the area did respond slightly to Cu added to the soil.

  5. Effects of CO2 enrichment and drought pretreatment on metabolite responses to water stress and subsequent rehydration using potato tubers from plants grown in sunlit SPAR chambers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were performed using naturally sunlit Soil–Plant–Atmosphere-Research chambers that provided ambient or elevated CO2. Potato plants were grown in pots that were water sufficient (W), water insufficient for 12 to 18 days during both vegetative and tuber development stages (VR), or water i...

  6. Health status of alfalfa leafcutting bee larvae (Hymenoptera: Megachilidae) in commercial United States alfalfa seed fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We conducted a geographically large survey to quantify production losses in the alfalfa leafcutting bee (Megachile rotundata, Hymenoptera: Megachilidae), a solitary pollinator used extensively in alfalfa seed production. Healthy prepupae were found in only 47.1% of the nest cells collected at the en...

  7. RNA-mediated gene silencing signals are not graft transmissible from the rootstock to the scion in greenhouse-grown apple plants Malus sp.

    PubMed

    Flachowsky, Henryk; Tränkner, Conny; Szankowski, Iris; Waidmann, Sascha; Hanke, Magda-Viola; Treutter, Dieter; Fischer, Thilo C

    2012-01-01

    RNA silencing describes the sequence specific degradation of RNA targets. Silencing is a non-cell autonomous event that is graft transmissible in different plant species. The present study is the first report on systemic acquired dsRNA-mediated gene silencing of transgenic and endogenous gene sequences in a woody plant like apple. Transgenic apple plants overexpressing a hairpin gene construct of the gusA reporter gene were produced. These plants were used as rootstocks and grafted with scions of the gusA overexpressing transgenic apple clone T355. After grafting, we observed a reduction of the gusA gene expression in T355 scions in vitro, but not in T355 scions grown in the greenhouse. Similar results were obtained after silencing of the endogenous Mdans gene in apple that is responsible for anthocyanin biosynthesis. Subsequently, we performed grafting experiments with Mdans silenced rootstocks and red leaf scions of TNR31-35 in order to evaluate graft transmitted silencing of the endogenous Mdans. The results obtained suggested a graft transmission of silencing signals in in vitro shoots. In contrast, no graft transmission of dsRNA-mediated gene silencing signals was detectable in greenhouse-grown plants and in plants grown in an insect protection tent. PMID:22949844

  8. Subpicosecond surface dynamics in genomic DNA from in vitro-grown plant species: a SERS assessment.

    PubMed

    Muntean, Cristina M; Bratu, Ioan; Leopold, Nicolae; Morari, Cristian; Buimaga-Iarinca, Luiza; Purcaru, Monica A P

    2015-09-01

    In this work the surface-enhanced Raman total half band widths of seven genomic DNAs from leaves of chrysanthemum (Dendranthema grandiflora Ramat.), common sundew (Drosera rotundifolia L.), edelweiss (Leontopodium alpinum Cass), Epilobium hirsutum L., Hypericum richeri ssp. transsilvanicum (Čelak) Ciocârlan, rose (Rosa x hybrida L.) and redwood (Sequoia sempervirens D. Don. Endl.) have been measured. We have shown that surface-enhanced Raman spectroscopy (SERS) can be used to study the fast subpicosecond dynamics of DNA in the proximity of a metallic surface. The dependencies of the total half band widths and the global relaxation times, on the DNA molecular subgroup structure and on the type of genomic DNA, are reported. In our study, the full widths at half-maximum (FWHMs) for the SERS bands of genomic DNAs from different leaf tissues are typically in the wavenumber range from 15 to 55 cm(-1). Besides, it can be observed that molecular relaxation processes studied in this work have a global relaxation time smaller than 0.71 ps and larger than 0.19 ps. A comparison between different ranges of FT-Raman and SERS band parameters, respectively, corresponding to DNA extracted from leaf tissues is given. It is shown that the interaction between DNA and a metallic surface has the potential to lead to a shortening of the global relaxation times, as compared with molecular dynamics in solution. We have found that the surface dynamics of molecular subgroups in plant DNA is, in some cases, about two times faster than the solution dynamics of nucleic acids. This can be rationalized in a qualitative manner by invoking the complex landscape of the interaction energy between the molecule and the silver surface. PMID:25687823

  9. Rate of Nitrogen Application during the Growing Season and Spraying Plants with Urea in the Autumn Alters Uptake of other Nutrients by Deciduous and Evergreen Container-Grown Rhododendron

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of N rate during the growing season and spraying plants with urea in the autumn on the uptake of other nutrients was assessed using container-grown rhododendron (Rhododendron 'H-1 P.J.M') and azalea (Rhododendron 'Cannon’s Double'). Plants were grown with a complete fertilizer containi...

  10. Preservation and Faithful Expression of Transgene via Artificial Seeds in Alfalfa

    PubMed Central

    Liu, Wenting; Liang, Zongsuo; Wang, Xinhua; Sibbald, Susan; Hunter, David; Tian, Lining

    2013-01-01

    Proper preservation of transgenes and transgenic materials is important for wider use of transgenic technology in plants. Here, we report stable preservation and faithful expression of a transgene via artificial seed technology in alfalfa. DNA constructs containing the uid reporter gene coding for β-glucuronidase (GUS) driven by a 35S promoter or a tCUP promoter were introduced into alfalfa via Agrobacterium-mediated genetic transformation. Somatic embryos were subsequently induced from transgenic alfalfa plants via in vitro technology. These embryos were treated with abscisic acid to induce desiccation tolerance and were subjected to a water loss process. After the desiccation procedure, the water content in dried embryos, or called artificial seeds, was about 12–15% which was equivalent to that in true seeds. Upon water rehydration, the dried somatic embryos showed high degrees of viability and exhibited normal germination. Full plants were subsequently developed and recovered in a greenhouse. The progeny plants developed from artificial seeds showed GUS enzyme activity and the GUS expression level was comparable to that of plants developed from somatic embryos without the desiccation process. Polymerase chain reaction analysis indicated that the transgene was well retained in the plants and Southern blot analysis showed that the transgene was stably integrated in plant genome. The research showed that the transgene and the new trait can be well preserved in artificial seeds and the progeny developed. The research provides a new method for transgenic germplasm preservation in different plant species. PMID:23690914

  11. Species and tissue type regulate long-term decomposition of brackish marsh plants grown under elevated CO2 conditions

    USGS Publications Warehouse

    Jones, Joshua A; Cherry, Julia A; Mckee, Karen L.

    2016-01-01

    Organic matter accumulation, the net effect of plant production and decomposition, contributes to vertical soil accretion in coastal wetlands, thereby playing a key role in whether they keep pace with sea-level rise. Any factor that affects decomposition may affect wetland accretion, including atmospheric CO2 concentrations. Higher CO2 can influence decomposition rates by altering plant tissue chemistry or by causing shifts in plant species composition or biomass partitioning. A combined greenhouse-field experiment examined how elevated CO2 affected plant tissue chemistry and subsequent decomposition of above- and belowground tissues of two common brackish marsh species, Schoenoplectus americanus (C3) and Spartina patens (C4). Both species were grown in monoculture and in mixture under ambient (350-385 μL L-1) or elevated (ambient + 300 μL L-1) atmospheric CO2 conditions, with all other growth conditions held constant, for one growing season. Above- and belowground tissues produced under these treatments were decomposed under ambient field conditions in a brackish marsh in the Mississippi River Delta, USA. Elevated CO2 significantly reduced nitrogen content of S. americanus, but not sufficiently to affect subsequent decomposition. Instead, long-term decomposition (percent mass remaining after 280 d) was controlled by species composition and tissue type. Shoots of S. patens had more mass remaining (41 ± 2%) than those of S. americanus (12 ± 2 %). Belowground material decomposed more slowly than that placed aboveground (62 ± 1% vs. 23 ± 3% mass remaining), but rates belowground did not differ between species. Increases in atmospheric CO2concentration will likely have a greater effect on overall decomposition in this brackish marsh community through shifts in species dominance or biomass allocation than through effects on tissue chemistry. Consequent changes in organic matter accumulation may alter marsh capacity to accommodate sea-level rise

  12. Alleviating salt stress in tomato seedlings using Arthrobacter and Bacillus megaterium isolated from the rhizosphere of wild plants grown on saline-alkaline lands.

    PubMed

    Fan, Pengfei; Chen, Daitao; He, Yanan; Zhou, Qingxia; Tian, Yongqiang; Gao, Lihong

    2016-11-01

    Salt-induced soil degradation is common in farmlands and limits the growth and development of numerous crop plants in the world. In this study, we isolated salt-tolerant bacteria from the rhizosphere of Tamarix chinensis, Suaeda salsa and Zoysia sinica, which are common wild plants grown on a saline-alkaline land, to test these bacteria's efficiency in alleviating salt stress in tomato plants. We screened out seven strains (TF1-7) that are efficient in reducing salt stress in tomato seedlings. The sequence data of 16S rRNA genes showed that these strains belong to Arthrobacter and Bacillus megaterium. All strains could hydrolyze casein and solubilize phosphate, and showed at least one plant growth promotion (PGP)-related gene, indicating their potential in promoting plant growth. The Arthrobacter strains TF1 and TF7 and the Bacillus megaterium strain TF2 and TF3 could produce indole acetic acid under salt stress, further demonstrating their PGP potential. Tomato seed germination, seedling length, vigor index, and plant fresh and dry weight were enhanced by inoculation of Arthrobacter and B. megaterium strains under salt stress. Our results demonstrated that salt-tolerant bacteria isolated from the rhizosphere of wild plants grown on saline-alkaline lands could be used for alleviating salt stress in crop plants. PMID:27196364

  13. "allometry" Deterministic Approaches in Cell Size, Cell Number and Crude Fiber Content Related to the Physical Quality of Kangkong (Ipomoea reptans) Grown Under Different Plant Density Pressures

    NASA Astrophysics Data System (ADS)

    Selamat, A.; Atiman, S. A.; Puteh, A.; Abdullah, N. A. P.; Mohamed, M. T. M.; Zulkeefli, A. A.; Othman, S.

    Kangkong, especially the upland type (Ipomoea reptans) is popularly consumed as a vegetable dish in the South East Asian countries for its quality related to Vitamins (A and C) and crude fiber contents. Higher fiber contents would prevent from the occurrence of colon cancer and diverticular disease. With young stem edible portion, its cell number and size contribute to the stem crude fiber content. The mathematical approach of allometry of cell size, number, and fiber content of stem could be used in determining the 'best' plant density pressure in producing the quality young stem to be consumed. Basically, allometry is the ratio of relative increment (growth or change) rates of two parameters, or the change rate associated to the log of measured variables relationship. Kangkog grown equal or lower than 55 plants m-2 produced bigger individual plant and good quality (physical) kangkong leafy vegetable, but with lower total yield per unit area as compared to those grown at higher densities.

  14. Proximate Composition of Seed and Biomass from Soybean Plants Grown at Different Carbon Dioxide (CO2) Concentrations

    NASA Technical Reports Server (NTRS)

    Wheeler, R. M.; Mackowiak, C. L.; Sager, J. C.

    1990-01-01

    Soybean plants were grown for 90 days at 500, 1000, 2000, and 5000 ubar (ppm) carbon dioxide (CO2) and compared for proximate nutritional value. For both cultivars (MC and PX), seed protein levels were highest at 1000 (39.3 and 41.9 percent for MC and PX) and lowest at 2000 (34.7 and 38.9 percent for MC and PX). Seed fat (oil) levels were highest at 2000 (21.2 and 20.9 percent for MC and PX) and lowest at 5000 (13.6 and 16.6 percent for MC and PX). Seed carbohydrate levels were highest at 500 (31.5 and 28.4 percent for MC and PX) and lowest at 2000 (20.9 and 20.8 percent for MC and PX). When adjusted for total seed yield per unit growing area, the highest production of protein and carbohydrate occurred with MC at 1000, while equally high amounts of fat were produced with MC at 1000 and 2000. Seed set and pod development at 2000 were delayed in comparison to other CO2 treatments; thus the proportionately high fat and low protein at 2000 may have been a result of the delay in plant maturity rather than CO2 concentration. Stem crude fiber and carbohydrate levels for both cultivars increased with increased CO2. Leaf protein and crude fiber levels also tended to rise with increased CO2 but leaf carbohydrate levels decreased as CO2 was increased. The results suggest that CO2 effects on total seed yield out-weighed any potential advantages to changes in seed composition.

  15. Effect of iron stress on Withania somnifera L.: antioxidant enzyme response and nutrient elemental uptake of in vitro grown plants.

    PubMed

    Rout, Jyoti Ranjan; Behera, Sadhana; Keshari, Nitin; Ram, Shidharth Sankar; Bhar, Subhajit; Chakraborty, Anindita; Sudarshan, Mathummal; Sahoo, Santi Lata

    2015-03-01

    In the present study the response of antioxidant enzyme activities and the level of expression of their corresponding genes on bioaccumulation of iron (Fe) were investigated. In vitro germinated Withania somnifera L. were grown in Murashige and Skoog's liquid medium with increasing concentrations (0, 25, 50, 100 and 200 µM) of FeSO4 for 7 and 14 days. Root and leaf tissues analyzed for catalase (CAT, EC 1.11.1.6), superoxide dismutase (SOD, EC 1.15.1.1) and guaiacol peroxidase (GPX, EC 1.11.1.7), have shown an increase in content with respect to exposure time. Isoforms of CAT, SOD and GPX were separated using non-denaturing polyacrylamide gel electrophoresis and observed that the isoenzymes were greatly affected by higher concentrations of Fe. Reverse transcriptase polymerase chain reaction analysis performed by taking three pairs of genes of CAT (RsCat, Catalase1, Cat1) and SOD (SodCp, TaSOD1.2, MnSOD) to find out the differential expression of antioxidant genes under Fe excess. RsCat from CAT and MnSOD from SOD have exhibited high levels of gene expression under Fe stress, which was consistent with the changes of the activity assayed in solution after 7 days of treatment. Analysis by proton induced X-ray emission exhibited an increasing uptake of Fe in plants by suppressing and expressing of other nutrient elements. The results of the present study suggest that higher concentration of Fe causes disturbance in nutrient balance and induces oxidative stress in plant. PMID:25480472

  16. Cash in on N credits when corn follows alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When alfalfa is killed, some of the accumulated N in the soil and in alfalfa leaves, stems, and roots becomes available to subsequent crops. This increased N supply is known as the “alfalfa N credit,” which is the amount of fertilizer or available manure N a grower can save, resulting in higher net ...

  17. Comparative drought response in eleven diverse alfalfa accessions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L.) production is often negatively affected by drought stress. This is particularly true for alfalfa that is cultivated on rangeland. Thus, the development of drought-tolerant alfalfa cultivars is of great significance. A greenhouse study was conducted to evaluate 11 alfa...

  18. Using genomics to develop alfalfa as a biomass crop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa is frequently overlooked as a biomass feedstock for cellulosic ethanol production. However, alfalfa has a number of advantages compared to other potential feedstocks. Alfalfa is a perennial, non-food crop that fixes atmospheric nitrogen, improves soil quality, and provides environmental bene...

  19. Alfalfa -- a sustainable crop for biomass energy production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa) has the potential to be a significant contributor to America's renewable energy future. In an alfalfa biomass energy production system, alfalfa forage would be separated into stem and leave fractions. The stems would be processed to produce energy, and the leaves would be s...

  20. Effect of wheel traffic and green manure treatments on forage yield and crown rot in alfalfa (Medicago sativa)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Harvesting alfalfa (Medicago sativa) results in mechanical wheel traffic on plants, which may damage crowns and increase the opportunity for entry of pathogens causing crown rot. Developing resistance to crown rot is problematic due to the large number of pathogens involved. Incorporation of plant b...

  1. The sky is falling II: Impact of deposition produced during the static testing of solid rocket motors on corn and alfalfa.

    PubMed

    Doucette, William J; Mendenhall, Scout; McNeill, Laurie S; Heavilin, Justin

    2014-06-01

    Tests of horizontally restrained rocket motors at the ATK facility in Promontory, Utah, USA result in the deposition of an estimated 1.5million kg of entrained soil and combustion products (mainly aluminum oxide, gaseous hydrogen chloride and water) on the surrounding area. The deposition is referred to as test fire soil (TFS). Farmers observing TFS deposited on their crops expressed concerns regarding the impact of this material. To address these concerns, we exposed corn and alfalfa to TFS collected during a September 2009 test. The impact was evaluated by comparing the growth and tissue composition of controls relative to the treatments. Exposure to TFS, containing elevated levels of chloride (1000 times) and aluminum (2 times) relative to native soils, affected the germination, growth and tissue concentrations of various elements, depending on the type and level of exposure. Germination was inhibited by high concentrations of TFS in soil, but the impact was reduced if the TFS was pre-leached with water. Biomass production was reduced in the TFS amended soils and corn grown in TFS amended soils did not develop kernels. Chloride concentrations in corn and alfalfa grown in TFS amended soils were two orders of magnitude greater than controls. TFS exposed plants contained higher concentrations of several cations, although the concentrations were well below livestock feed recommendations. Foliar applications of TFS had no impact on biomass, but some differences in the elemental composition of leaves relative to controls were observed. Washing the TFS off the leaves lessened the impact. Results indicate that the TFS deposition could have an effect, depending on the amount and growth stage of the crops, but the impact could be mitigated with rainfall or the application of additional irrigation water. The high level of chloride associated with the TFS is the main cause of the observed impacts. PMID:24632062

  2. Transcriptome responses in alfalfa associated with tolerance to intensive animal grazing

    PubMed Central

    Wang, Junjie; Zhao, Yan; Ray, Ian; Song, Mingzhou

    2016-01-01

    Tolerance of alfalfa (Medicago sativa L.) to animal grazing varies widely within the species. However, the molecular mechanisms influencing the grazing tolerant phenotype remain uncharacterized. The objective of this study was to identify genes and pathways that control grazing response in alfalfa. We analyzed whole-plant de novo transcriptomes from grazing tolerant and intolerant populations of M. sativa ssp. falcata subjected to grazing by sheep. Among the Gene Ontology terms which were identified as grazing responsive in the tolerant plants and differentially enriched between the tolerant and intolerant populations (both grazed), most were associated with the ribosome and translation-related activities, cell wall processes, and response to oxygen levels. Twenty-one grazing responsive pathways were identified that also exhibited differential expression between the tolerant and intolerant populations. These pathways were associated with secondary metabolite production, primary carbohydrate metabolic pathways, shikimate derivative dependent pathways, ribosomal subunit composition, hormone signaling, wound response, cell wall formation, and anti-oxidant defense. Sequence polymorphisms were detected among several differentially expressed homologous transcripts between the tolerant and intolerant populations. These differentially responsive genes and pathways constitute potential response mechanisms for grazing tolerance in alfalfa. They also provide potential targets for molecular breeding efforts to develop grazing-tolerant cultivars of alfalfa. PMID:26763747

  3. The Undergraduate ALFALFA Team: Collaborative Research Projects

    NASA Astrophysics Data System (ADS)

    Cannon, John M.; Koopmann, Rebecca A.; Haynes, Martha P.; Undergraduate ALFALFA Team, ALFALFA Team

    2016-01-01

    The NSF-sponsored Undergraduate ALFALFA (Arecibo Legacy Fast ALFA) Team (UAT) has allowed faculty and students from a wide range of public and private colleges and especially those with small astronomy programs to learn how science is accomplished in a large collaboration while contributing to the scientific goals of a legacy radio astronomy survey. The UAT has achieved this through close collaboration with ALFALFA PIs to identify research areas accessible to undergraduates. In this talk we will summarize the main research efforts of the UAT, including multiwavelength followup observations of ALFALFA sources, the UAT Collaborative Groups Project, the Survey of HI in Extremely Low-mass Dwarfs (SHIELD), and the Arecibo Pisces-Perseus Supercluster Survey. This work has been supported by NSF grants AST-0724918/0902211, AST-075267/0903394, AST-0725380, and AST-1211005.

  4. Tritium dynamics in soils and plants grown under three irrigation regimes at a tritium processing facility in Canada.

    PubMed

    Mihok, S; Wilk, M; Lapp, A; St-Amant, N; Kwamena, N-O A; Clark, I D

    2016-03-01

    The dynamics of tritium released from nuclear facilities as tritiated water (HTO) have been studied extensively with results incorporated into regulatory assessment models. These models typically estimate organically bound tritium (OBT) for calculating public dose as OBT itself is rarely measured. Higher than expected OBT/HTO ratios in plants and soils are an emerging issue that is not well understood. To support the improvement of models, an experimental garden was set up in 2012 at a tritium processing facility in Pembroke, Ontario to characterize the circumstances under which high OBT/HTO ratios may arise. Soils and plants were sampled weekly to coincide with detailed air and stack monitoring. The design included a plot of native grass/soil, contrasted with sod and vegetables grown in barrels with commercial topsoil under natural rain and either low or high tritium irrigation water. Air monitoring indicated that the plume was present infrequently at concentrations of up to about 100 Bq/m(3) (the garden was not in a major wind sector). Mean air concentrations during the day on workdays (HTO 10.3 Bq/m(3), HT 5.8 Bq/m(3)) were higher than at other times (0.7-2.6 Bq/m(3)). Mean Tissue Free Water Tritium (TFWT) in plants and soils and OBT/HTO ratios were only very weakly or not at all correlated with releases on a weekly basis. TFWT was equal in soils and plants and in above and below ground parts of vegetables. OBT/HTO ratios in above ground parts of vegetables were above one when the main source of tritium was from high tritium irrigation water (1.5-1.8). Ratios were below one in below ground parts of vegetables when irrigated with high tritium water (0.4-0.6) and above one in vegetables rain-fed or irrigated with low tritium water (1.3-2.8). In contrast, OBT/HTO ratios were very high (9.0-13.5) when the source of tritium was mainly from the atmosphere. TFWT varied considerably through time as a result of SRBT's operations; OBT/HTO ratios showed no clear temporal

  5. Effects of Soil pH on Reproduction of Pratylenchus penetrans and Forage Yield of Alfalfa

    PubMed Central

    Willis, C. B.

    1972-01-01

    'Vernal' alfalfa was grown for 30 weeks in nematode-free soil and in soil infested with Pratylenchus penetrans. Charlottetown fine sandy loam soil was used at its pH of 4.4 and at adjusted reactions of 5.2, 6.4 and 7.3. Nematode reproduction was significantly greater at pit 5.2 and 6.4 and was not related to alfalfa root production over the full pH range studied. A significant nematode infestation X soil pit interaction on forage yield was recorded. Nematode infestation significantly decreased forage yields at ptt 5.2 and 6.4 but not at pH 4.4 and 7.3. PMID:19319283

  6. The role of growth form and correlated traits in competitive ranking of six perennial ruderal plant species grown in unbalanced mixtures

    NASA Astrophysics Data System (ADS)

    Dietz, Hansjörg; Steinlein, Thomas; Ullmann, Isolde

    1998-02-01

    The competitive abilities of six perennial ruderal plants of three different growth forms were compared via yield measures using an additive diallel experimental design with unbalanced mixtures (9:3 or 3:9 plants per pot, respectively). Thus, in a given mixture species A was grown in two configurations: three individuals in centre position of the pot together with nine plants of species B in border position and vice versa. Effect competitive abilities as well as response competitive abilities of the species were significantly related to canopy height and plant biomass. The species with lower rosette growth form and smaller biomasses were weaker competitors than the species possessing elevated canopies along with higher biomasses, whereas total leaf area was not significantly correlated with competitive ability between species. Species differences in competitive ability were stronger between the plants grown in the central position than between those grown in the border position. Furthermore, interactions between species-specific traits and configuration could be observed, indicating the importance of species proportions and arrangement patterns for evaluation of competitive outcome in the field. The degree of complete transitivity of the competitive network of the six ruderal species, which was significantly higher than expected under the null model in our experimental design, also seemed to depend on species proportions in mixture. Shifts in root:shoot ratio of the centre plants when faced with competition by the border plants were in the direction of higher shoot allocation for the weak competitors with rosette growth form irrespective of the neighbour species, except for Bunias orientalis, which showed a more plastic response. The stronger competitors showed higher root allocation ( Urtica dioica) or were hardly affected at all. Consistent with the results of our experiment, the weaker competitors occur at rather frequently disturbed and therefore transient

  7. [Cation exchanges during the process of Cd(2+) absorption by Alfalfa in aqueous solutions].

    PubMed

    Li, Yue-Peng; Yin, Hua; Ye, Jin-Shao; Peng, Hua; Qin, Hua-Ming; Long, Yan; He, Bao-Yan; Zhang, Na; Tong, Yao; Peng, Su-Fen

    2011-11-01

    A hydroponic experiment was conducted to investigate the cation exchanges during the process of Cd2+ absorption by Alfalfa in aqueous solution. The absorption efficiency of Alfalfa plants with 0-10 mg x L(-1) Cd2+ treatments, changes of Na+, K+, Mg2+, Ca2+ and NH4(+) concentration, and the variation of pH values at different absorption time (0, 1, 2, 4, 8, 12, 24 and 72 h) were studied separately. The multiple linear regressions between Cd2+ absorption and cation variation were analyzed. The results indicated that when Cd2+ concentrations were 0.1, 1, 5, 10 mg x L(-1), the absorption efficiencies of Cd2+ by Alfalfa after 72 h were 85.86%, 52.14%, 15.97% and 7.81%. Cation exchange was involved in the removal of Cd2+ by Alfalfa in aqueous solution. Except for NH4(+), the concentrations of cationic metals Na+, K+, Mg2+ and Ca2+ in aqueous solution increased over time, which increased 11.30% - 61.72%, 21.44% - 98.73%, 24.09% - 8.90% and 37.04% - 191.96%, respectively. Kinetic studies illuminated that the release of Na+, K+, Mg2+ and Ca2+ by Alfalfa in Cd2+ solution with initial concentrations of 0, 0. 1, 1, 5, 10 mg x L(-1) best fitted pseudo-second-order equation,while the NH4(+) release fitted this model when Cd2+ concentrations were 1, 5, 10 mg x L(-1). The gradual decrease of pH during adsorption of Cd2+ by Alfalfa was observed. As the competition ion of Cd2+, H+ might affect the capacity of Alfalfa root system to absorb Cd2+. The ternary linear equation results demonstrated that the content of Cd2+ absorption by Alfalfa strongly related with the release of Ca2+, Mg2+, Na+. And this exchange mainly occurred among Cd2+ and divalent cations. PMID:22295633

  8. Changes in Whole-Plant Metabolism during the Grain-Filling Stage in Sorghum Grown under Elevated CO2 and Drought.

    PubMed

    De Souza, Amanda P; Cocuron, Jean-Christophe; Garcia, Ana Carolina; Alonso, Ana Paula; Buckeridge, Marcos S

    2015-11-01

    Projections indicate an elevation of the atmospheric CO2 concentration ([CO2]) concomitant with an intensification of drought for this century, increasing the challenges to food security. On the one hand, drought is a main environmental factor responsible for decreasing crop productivity and grain quality, especially when occurring during the grain-filling stage. On the other hand, elevated [CO2] is predicted to mitigate some of the negative effects of drought. Sorghum (Sorghum bicolor) is a C4 grass that has important economical and nutritional values in many parts of the world. Although the impact of elevated [CO2] and drought in photosynthesis and growth has been well documented for sorghum, the effects of the combination of these two environmental factors on plant metabolism have yet to be determined. To address this question, sorghum plants (cv BRS 330) were grown and monitored at ambient (400 µmol mol(-1)) or elevated (800 µmol mol(-1)) [CO2] for 120 d and subjected to drought during the grain-filling stage. Leaf photosynthesis, respiration, and stomatal conductance were measured at 90 and 120 d after planting, and plant organs (leaves, culm, roots, prop roots, and grains) were harvested. Finally, biochemical composition and intracellular metabolites were assessed for each organ. As expected, elevated [CO2] reduced the stomatal conductance, which preserved soil moisture and plant fitness under drought. Interestingly, the whole-plant metabolism was adjusted and protein content in grains was improved by 60% in sorghum grown under elevated [CO2]. PMID:26336093

  9. Changes in Whole-Plant Metabolism during the Grain-Filling Stage in Sorghum Grown under Elevated CO2 and Drought1[OPEN

    PubMed Central

    De Souza, Amanda P.; Cocuron, Jean-Christophe; Garcia, Ana Carolina; Alonso, Ana Paula; Buckeridge, Marcos S.

    2015-01-01

    Projections indicate an elevation of the atmospheric CO2 concentration ([CO2]) concomitant with an intensification of drought for this century, increasing the challenges to food security. On the one hand, drought is a main environmental factor responsible for decreasing crop productivity and grain quality, especially when occurring during the grain-filling stage. On the other hand, elevated [CO2] is predicted to mitigate some of the negative effects of drought. Sorghum (Sorghum bicolor) is a C4 grass that has important economical and nutritional values in many parts of the world. Although the impact of elevated [CO2] and drought in photosynthesis and growth has been well documented for sorghum, the effects of the combination of these two environmental factors on plant metabolism have yet to be determined. To address this question, sorghum plants (cv BRS 330) were grown and monitored at ambient (400 µmol mol−1) or elevated (800 µmol mol−1) [CO2] for 120 d and subjected to drought during the grain-filling stage. Leaf photosynthesis, respiration, and stomatal conductance were measured at 90 and 120 d after planting, and plant organs (leaves, culm, roots, prop roots, and grains) were harvested. Finally, biochemical composition and intracellular metabolites were assessed for each organ. As expected, elevated [CO2] reduced the stomatal conductance, which preserved soil moisture and plant fitness under drought. Interestingly, the whole-plant metabolism was adjusted and protein content in grains was improved by 60% in sorghum grown under elevated [CO2]. PMID:26336093

  10. Biodegradation of atrazine in transgenic plants expressing a modified bacterial atrazine chlorohydrolase (atzA) gene.

    PubMed

    Wang, Lin; Samac, Deborah A; Shapir, Nir; Wackett, Lawrence P; Vance, Carroll P; Olszewski, Neil E; Sadowsky, Michael J

    2005-09-01

    Atrazine is one of the most widely used herbicides in the USA. Atrazine chlorohydrolase (AtzA), the first enzyme in a six-step pathway leading to the mineralization of atrazine in Gram-negative soil bacteria, catalyses the hydrolytic dechlorination and detoxification of atrazine to hydroxyatrazine. In this study, we investigated the potential use of transgenic plants expressing atzA to take up, dechlorinate and detoxify atrazine. Alfalfa, Arabidopsis thaliana and tobacco were transformed with a modified bacterial atzA gene, p-atzA, under the control of the cassava vein mosaic virus promoter. All transgenic plant species actively expressed p-atzA and grew over a wide range of atrazine concentrations. Thin layer chromatography analyses indicated that in planta expression of p-atzA resulted in the production of hydroxyatrazine. Hydroponically grown transgenic tobacco and alfalfa dechlorinated atrazine to hydroxyatrazine in leaves, stems and roots. Moreover, p-atzA was found to be useful as a conditional-positive selection system to isolate alfalfa and Arabidopsis transformants following Agrobacterium-mediated transformation. Our work suggests that the in planta expression of p-atzA may be useful for the development of plants for the phytoremediation of atrazine-contaminated soils and soil water, and as a marker gene to select for the integration of exogenous DNA into the plant genome. PMID:17173634

  11. Effect of bacterial root symbiosis and urea as source of nitrogen on performance of soybean plants grown hydroponically for Bioregenerative Life Support Systems (BLSSs).

    PubMed

    Paradiso, Roberta; Buonomo, Roberta; Dixon, Mike A; Barbieri, Giancarlo; De Pascale, Stefania

    2015-01-01

    Soybean is traditionally grown in soil, where root symbiosis with Bradyrhizobium japonicum can supply nitrogen (N), by means of bacterial fixation of atmospheric N2. Nitrogen fertilizers inhibit N-fixing bacteria. However, urea is profitably used in soybean cultivation in soil, where urease enzymes of telluric microbes catalyze the hydrolysis to ammonium, which has a lighter inhibitory effect compared to nitrate. Previous researches demonstrated that soybean can be grown hydroponically with recirculating complete nitrate-based nutrient solutions. In Space, urea derived from crew urine could be used as N source, with positive effects in resource procurement and waste recycling. However, whether the plants are able to use urea as the sole source of N and its effect on root symbiosis with B. japonicum is still unclear in hydroponics. We compared the effect of two N sources, nitrate and urea, on plant growth and physiology, and seed yield and quality of soybean grown in closed-loop Nutrient Film Technique (NFT) in growth chamber, with or without inoculation with B. japonicum. Urea limited plant growth and seed yield compared to nitrate by determining nutrient deficiency, due to its low utilization efficiency in the early developmental stages, and reduced nutrients uptake (K, Ca, and Mg) throughout the whole growing cycle. Root inoculation with B. japonicum did not improve plant performance, regardless of the N source. Specifically, nodulation increased under fertigation with urea compared to nitrate, but this effect did not result in higher leaf N content and better biomass and seed production. Urea was not suitable as sole N source for soybean in closed-loop NFT. However, the ability to use urea increased from young to adult plants, suggesting the possibility to apply it during reproductive phase or in combination with nitrate in earlier developmental stages. Root symbiosis did not contribute significantly to N nutrition and did not enhance the plant ability to use

  12. Effect of bacterial root symbiosis and urea as source of nitrogen on performance of soybean plants grown hydroponically for Bioregenerative Life Support Systems (BLSSs)

    PubMed Central

    Paradiso, Roberta; Buonomo, Roberta; Dixon, Mike A.; Barbieri, Giancarlo; De Pascale, Stefania

    2015-01-01

    Soybean is traditionally grown in soil, where root symbiosis with Bradyrhizobium japonicum can supply nitrogen (N), by means of bacterial fixation of atmospheric N2. Nitrogen fertilizers inhibit N-fixing bacteria. However, urea is profitably used in soybean cultivation in soil, where urease enzymes of telluric microbes catalyze the hydrolysis to ammonium, which has a lighter inhibitory effect compared to nitrate. Previous researches demonstrated that soybean can be grown hydroponically with recirculating complete nitrate-based nutrient solutions. In Space, urea derived from crew urine could be used as N source, with positive effects in resource procurement and waste recycling. However, whether the plants are able to use urea as the sole source of N and its effect on root symbiosis with B. japonicum is still unclear in hydroponics. We compared the effect of two N sources, nitrate and urea, on plant growth and physiology, and seed yield and quality of soybean grown in closed-loop Nutrient Film Technique (NFT) in growth chamber, with or without inoculation with B. japonicum. Urea limited plant growth and seed yield compared to nitrate by determining nutrient deficiency, due to its low utilization efficiency in the early developmental stages, and reduced nutrients uptake (K, Ca, and Mg) throughout the whole growing cycle. Root inoculation with B. japonicum did not improve plant performance, regardless of the N source. Specifically, nodulation increased under fertigation with urea compared to nitrate, but this effect did not result in higher leaf N content and better biomass and seed production. Urea was not suitable as sole N source for soybean in closed-loop NFT. However, the ability to use urea increased from young to adult plants, suggesting the possibility to apply it during reproductive phase or in combination with nitrate in earlier developmental stages. Root symbiosis did not contribute significantly to N nutrition and did not enhance the plant ability to use

  13. Salt stress alters DNA methylation levels in alfalfa (Medicago spp).

    PubMed

    Al-Lawati, A; Al-Bahry, S; Victor, R; Al-Lawati, A H; Yaish, M W

    2016-01-01

    Modification of DNA methylation status is one of the mechanisms used by plants to adjust gene expression at both the transcriptional and posttranscriptional levels when plants are exposed to suboptimal conditions. Under abiotic stress, different cultivars often show heritable phenotypic variation accompanied by epigenetic polymorphisms at the DNA methylation level. This variation may provide the raw materials for plant breeding programs that aim to enhance abiotic stress tolerance, including salt tolerance. In this study, methylation-sensitive amplified polymorphism (MSAP) analysis was used to assess cytosine methylation levels in alfalfa (Medicago spp) roots exposed to increasing NaCl concentrations (0.0, 8.0, 12.0, and 20.0 dS/m). Eleven indigenous landraces were analyzed, in addition to a salt-tolerant cultivar that was used as a control. There was a slight increase in DNA methylation upon exposure to high levels of soil salinity. Phylogenetic analysis using MSAP showed epigenetic variation within and between the alfalfa landraces when exposed to saline conditions. Based on MSAP and enzyme-linked immunosorbent assay results, we found that salinity increased global DNA methylation status, particularly in plants exposed to the highest level of salinity (20 dS/m). Quantitative reverse transcription-polymerase chain reaction indicated that this might be mediated by the overexpression of methyltransferase homolog genes after exposure to saline conditions. DNA demethylation using 5-azacytidine reduced seedling lengths and dry and fresh weights, indicating a possible decrease in salinity tolerance. These results suggest that salinity affects DNA methylation flexibility. PMID:26985924

  14. Characterization of plant growth promoting traits of bacterial isolates from the rhizosphere of barley (Hordeum vulgare L.) and tomato (Solanum lycopersicon L.) grown under Fe sufficiency and deficiency.

    PubMed

    Scagliola, M; Pii, Y; Mimmo, T; Cesco, S; Ricciuti, P; Crecchio, C

    2016-10-01

    Plant Growth Promoting Bacteria (PGPB) are considered a promising approach to replace the conventional agricultural practices, since they have been shown to affect plant nutrient-acquisition processes by influencing nutrient availability in the rhizosphere and/or those biochemical processes determining the uptake at root level of nitrogen (N), phosphorus (P), and iron (Fe), that represent the major constraints for crop productivity worldwide. We have isolated novel bacterial strains from the rhizosphere of barley (Hordeum vulgare L.) and tomato (Solanum lycopersicon L.) plants, previously grown in hydroponic solution (either Fe deficient or Fe sufficient) and subsequently transferred onto an agricultural calcareous soil. PGPB have been identified by molecular tools and characterized for their capacity to produce siderophores and indole-3-acetic acid (IAA), and to solubilize phosphate. Selected bacterial isolates, showing contemporarily high levels of the three activities investigated, were finally tested for their capacity to induce Fe reduction in cucumber roots two isolates, from barley and tomato plants under Fe deficiency, significantly increased the root Fe-chelate reductase activity; interestingly, another isolate enhanced the reduction of Fe-chelate reductase activity in cucumber plant roots, although grown under Fe sufficiency. PMID:27295343

  15. MANURE MANAGEMENT: ALFALFA FIELDS GIVE US OPTIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The average cow in the U.S. produces more than 18,000 lbs. of milk each year and generates about 42,000 lbs. of manure. Manure management is not the only task on the farmer's 'to do' list, but in today’s world it is increasingly important to do it right. Although alfalfa acreage is a relatively smal...

  16. Alfalfa production using saline drainage water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A three year study investigated the use of saline (< 6 dS/m) drainage water for irrigation of salt tolerant alfalfa in the presence of shallow saline groundwater. The irrigation treatments included; irrigating twice between cuttings with non-saline water, 2) irrigating with moderately saline water...

  17. Sativa by falcata alfalfa hybrid variety trials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research has demonstrated that alfalfa (Medicago sativa L.) subsp. sativa by subsp. falcata hybrids showed heterosis. Limited work has been done examining these hybrids in a sward situation. The objective of this study was to produce sativa by falcata hybrids using Dairyland Seed Company’...

  18. N fixation versus N uptake in alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fertilizer N is the single most expensive input in nearly all crop-production systems and has been implicated in declining groundwater quality due to nitrate contamination. Commercial alfalfas are highly productive in the absence of nitrogen inputs because of the symbiotic association with soil bact...

  19. ALFALFA TRAITS THAT WILL IMPACT BIOENERGY PRODUCTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in production of energy from renewable resources such as biomass has increased tremendously with the recent price spike for oil and growing recognition of the threat posed by global warming. Alfalfa is an attractive alternative for biomass production because of its perennial nature, ability...

  20. Co-transforming bar and CsLEA enhanced tolerance to drought and salt stress in transgenic alfalfa (Medicago sativa L.).

    PubMed

    Zhang, Jiyu; Duan, Zhen; Zhang, Daiyu; Zhang, Jianquan; Di, Hongyan; Wu, Fan; Wang, Yanrong

    2016-03-25

    Drought and high salinity are two major abiotic factors that restrict alfalfa productivity. A dehydrin protein, CsLEA, from the desert grass Cleistogenes songorica was transformed into alfalfa (Medicago sativa L.) via Agrobacterium-mediated transformation using the bar gene as a selectable marker, and the drought and salt stress tolerances of the transgenic plants were assessed. Thirty-nine of 119 transformants were positive, as screened by Basta, and further molecularly authenticated using PCR and RT-PCR. Phenotype observations revealed that the transgenic plants grew better than the wild-type (WT) plants after 15d of drought stress and 10d of salt stress: the leaves of WT alfalfa turned yellow, whereas the transgenic alfalfa leaves only wilted; after rewatering, the transgenic plants returned to a normal state, though the WT plants could not be restored. Evaluation of physiologic and biochemical indices during drought and salt stresses showed a relatively lower Na(+) content in the leaves of the transgenic plants, which would reduce toxic ion effects. In addition, the transgenic plants were able to maintain a higher relative water content (RWC), higher shoot biomass, fewer photosystem changes, decreased membrane injury, and a lower level of osmotic stress injury. These results demonstrate that overexpression of the CsLEA gene can enhance the drought and salt tolerance of transgenic alfalfa; in addition, carrying the bar gene in the genome may increase herbicide resistance. PMID:26906624

  1. NADH-Glutamate Synthase in Alfalfa Root Nodules. Immunocytochemical Localization1

    PubMed Central

    Trepp, Gian B.; Plank, David W.; Stephen Gantt, J.; Vance, Carroll P.

    1999-01-01

    In root nodules of alfalfa (Medicago sativa L.), N2 is reduced to NH4+ in the bacteroid by the nitrogenase enzyme and then released into the plant cytosol. The NH4+ is then assimilated by the combined action of glutamine synthetase (EC 6.3.1.2) and NADH-dependent Glu synthase (NADH-GOGAT; EC 1.4.1.14) into glutamine and Glu. The alfalfa nodule NADH-GOGAT protein has a 101-amino acid presequence, but the subcellular location of the protein is unknown. Using immunocytochemical localization, we determined first that the NADH-GOGAT protein is found throughout the infected cell region of both 19- and 33-d-old nodules. Second, in alfalfa root nodules NADH-GOGAT is localized predominantly to the amyloplast of infected cells. This finding, together with earlier localization and fractionation studies, indicates that in alfalfa the infected cells are the main location for the initial assimilation of fixed N2. PMID:10069822

  2. Studies on mycorrhizal inoculation on dry matter yield and root colonization of some medicinal plants grown in stress and forest soils.

    PubMed

    Chandra, K K; Kumar, Neeraj; Chand, Gireesh

    2010-11-01

    Five medicinal plants viz. Abelmoschatus moschatus Linn., Clitoria tematea L., Plumbagozeylanica L., Psorolea corylifolia L. and Withania sominifera L. were grown in a polypot experiment in five soils representing coal mine soil, coppermine soil, fly ash, skeletal soil and forest soil with and without mycorrhizal inoculations in a completely randomized block design. Dry matter yield and mycorrhizal root colonization of plants varied both in uninoculated and inoculated conditions. The forest soil rendered highest dry matter due to higher yield of A. moschatus, P. zeylanica and P corylifolia while fly ash showed lowest dry matter without any inoculants. P. cematea were best in coalmine soil and W. sominifera in copper mine soil without mycorrhizal inoculation. The mycorrhiza was found to enhance the dry matter yield. This contributed minimum 0.19% to maximum up to 422.0% in different soils as compared to uninoculated plants. The mycorrhizal dependency was noticed maximum in plants grown in fly ash followed by coal mine soil, copper mine soil, skeletal soil and forest soil. The mycorrhizal response was increased maximum in W. sominifera due to survival in fly ash after inoculation followed by P corylifolia and P cematea. Percent root colonization in inoculated plant was increased minimum of 1.10 fold to maximum of 12.0 folds in comparison to un-inoculated plants . The native mycorrhiza fungi were also observed to colonize 4.0 to 32.0% roots in plants understudy. This study suggests that mycorrhizal inoculation increased the dry matter yield of medicinal plants in all soils under study. It also helps in survival of W. sominifera in fly ash. PMID:21506485

  3. Effect of Arbuscular Mycorrhizal Fungi on Plant Biomass and the Rhizosphere Microbial Community Structure of Mesquite Grown in Acidic Lead/Zinc Mine Tailings

    PubMed Central

    Solís-Domínguez, Fernando A.; Valentín-Vargas, Alexis; Chorover, Jon; Maier, Raina M.

    2011-01-01

    Mine tailings in arid and semi-arid environments are barren of vegetation and subject to eolian dispersion and water erosion. Revegetation is a cost-effective strategy to reduce erosion processes and has wide public acceptance. A major cost of revegetation is the addition of amendments, such as compost, to allow plant establishment. In this paper we explore whether arbuscular mycorrhizal fungi (AMF) can help support plant growth in tailings at a reduced compost concentration. A greenhouse experiment was performed to determine the effects of three AMF inocula on biomass, shoot accumulation of heavy metals, and changes in the rhizosphere microbial community structure of the native plant Prosopis juliflora (mesquite). Plants were grown in an acidic lead/zinc mine tailings amended with 10% (w/w) compost amendment, which is slightly sub-optimal for plant growth in these tailings. After two months, AMF-inoculated plants showed increased dry biomass and root length (p < 0.05) and effective AMF colonization compared to controls grown in uninoculated compost-amended tailings. Mesquite shoot tissue lead and zinc concentrations did not exceed domestic animal toxicity limits regardless of whether AMF inoculation was used. The rhizosphere microbial community structure was assessed using denaturing gradient gel electrophoresis (DGGE) profiles of the small subunit RNA gene for bacteria and fungi. Canonical correspondence analysis (CCA) of DGGE profiles showed that the rhizosphere fungal community structure at the end of the experiment was significantly different from the community structure in the tailings, compost, and AMF inocula prior to planting. Further, CCA showed that AMF inoculation significantly influenced the development of both the fungal and bacterial rhizosphere community structures after two months. The changes observed in the rhizosphere microbial community structure may be either a direct effect of the AMF inocula, caused by changes in plant physiology induced by

  4. Enhanced Botrytis cinerea Resistance of Arabidopsis Plants Grown in Compost May Be Explained by Increased Expression of Defense-Related Genes, as Revealed by Microarray Analysis

    PubMed Central

    Segarra, Guillem; Santpere, Gabriel; Elena, Georgina; Trillas, Isabel

    2013-01-01

    Composts are the products obtained after the aerobic degradation of different types of organic matter waste and can be used as substrates or substrate/soil amendments for plant cultivation. There is a small but increasing number of reports that suggest that foliar diseases may be reduced when using compost, rather than standard substrates, as growing medium. The purpose of this study was to examine the gene expression alteration produced by the compost to gain knowledge of the mechanisms involved in compost-induced systemic resistance. A compost from olive marc and olive tree leaves was able to induce resistance against Botrytis cinerea in Arabidopsis, unlike the standard substrate, perlite. Microarray analyses revealed that 178 genes were differently expressed, with a fold change cut-off of 1, of which 155 were up-regulated and 23 were down-regulated in compost-grown, as against perlite-grown plants. A functional enrichment study of up-regulated genes revealed that 38 Gene Ontology terms were significantly enriched. Response to stress, biotic stimulus, other organism, bacterium, fungus, chemical and abiotic stimulus, SA and ABA stimulus, oxidative stress, water, temperature and cold were significantly enriched, as were immune and defense responses, systemic acquired resistance, secondary metabolic process and oxireductase activity. Interestingly, PR1 expression, which was equally enhanced by growing the plants in compost and by B. cinerea inoculation, was further boosted in compost-grown pathogen-inoculated plants. Compost triggered a plant response that shares similarities with both systemic acquired resistance and ABA-dependent/independent abiotic stress responses. PMID:23405252

  5. Enhanced Botrytis cinerea resistance of Arabidopsis plants grown in compost may be explained by increased expression of defense-related genes, as revealed by microarray analysis.

    PubMed

    Segarra, Guillem; Santpere, Gabriel; Elena, Georgina; Trillas, Isabel

    2013-01-01

    Composts are the products obtained after the aerobic degradation of different types of organic matter waste and can be used as substrates or substrate/soil amendments for plant cultivation. There is a small but increasing number of reports that suggest that foliar diseases may be reduced when using compost, rather than standard substrates, as growing medium. The purpose of this study was to examine the gene expression alteration produced by the compost to gain knowledge of the mechanisms involved in compost-induced systemic resistance. A compost from olive marc and olive tree leaves was able to induce resistance against Botrytis cinerea in Arabidopsis, unlike the standard substrate, perlite. Microarray analyses revealed that 178 genes were differently expressed, with a fold change cut-off of 1, of which 155 were up-regulated and 23 were down-regulated in compost-grown, as against perlite-grown plants. A functional enrichment study of up-regulated genes revealed that 38 Gene Ontology terms were significantly enriched. Response to stress, biotic stimulus, other organism, bacterium, fungus, chemical and abiotic stimulus, SA and ABA stimulus, oxidative stress, water, temperature and cold were significantly enriched, as were immune and defense responses, systemic acquired resistance, secondary metabolic process and oxireductase activity. Interestingly, PR1 expression, which was equally enhanced by growing the plants in compost and by B. cinerea inoculation, was further boosted in compost-grown pathogen-inoculated plants. Compost triggered a plant response that shares similarities with both systemic acquired resistance and ABA-dependent/independent abiotic stress responses. PMID:23405252

  6. Soil sulfur amendments suppress selenium uptake by alfalfa and Western wheatgrass.

    PubMed

    Mackowiak, C L; Amacher, M C

    2008-01-01

    Selenium (Se) is a potential soil contaminant in many parts of the world where it can pose a health risk to livestock and wildlife. Phosphate ore mining in Southeast Idaho has resulted in numerous waste rock dumps revegetated with forages to stabilize the dumps and support grazing. Alfalfa (Medicago sativa L.), smooth brome (Bromus inermis Leyss.), and western wheat grass [Pascopyrum smithii (Rydb.) A. Löve] are the dominant forage species on these lands. To demonstrate the feasibility of using sulfur (S) as a soil amendment to restrict plant Se uptake, 3 kg pots containing 50:50 w/w soil and waste shale were uniformly mixed with 0, 0.5, 1.0, or 2.0 Mg ha(-1) S as either elemental S or gypsum. Pots were seeded with alfalfa or western wheat grass. Dry mass and tissue Se were monitored over several clippings. Soils were sampled at the conclusion of the study and analyzed for water-soluble, oxalate-extractable, and total Se. Sulfur amendments as either elemental S or gypsum at 1.0 Mg ha(-1) or greater equally suppressed Se uptake over 60% in both forage species. Alfalfa accumulated more Se than western wheat grass. Plant removal via successive clippings resulted in lower tissue Se accumulation over time than the use of S soil amendments alone. Alfalfa-planted soils contained lower water-soluble and oxalate-extractable Se than did the non-planted controls while western wheat grass-planted soils contained lower water-soluble Se. Applying S to these shale-based soils may be an economically viable option for treating Se-impacted, revegetated lands. PMID:18453397

  7. Protein accumulation and rumen stability of wheat γ-gliadin fusion proteins in tobacco and alfalfa.

    PubMed

    Sun, Xiaodong; Chi-Ham, Cecilia L; Cohen-Davidyan, Tamar; DeBen, Christopher; Getachow, Girma; DePeters, Edward; Putnam, Daniel; Bennett, Alan

    2015-09-01

    The nutritional value of various crops can be improved by engineering plants to produce high levels of proteins. For example, because methionine deficiency limits the protein quality of Medicago Sativa (alfalfa) forage, producing alfalfa plants that accumulate high levels of a methionine-rich protein could increase the nutritional value of that crop. We used three strategies in designing methionine-rich recombinant proteins that could accumulate to high levels in plants and thereby serve as candidates for improving the protein quality of alfalfa forage. In tobacco, two fusion proteins, γ-gliadin-δ-zein and γ-δ-zein, as well as δ-zein co-expressed with β-zein, all formed protein bodies. However, the γ-gliadin-δ-zein fusion protein accumulated to the highest level, representing up to 1.5% of total soluble protein (TSP) in one transformant. In alfalfa, γ-gliadin-δ-zein accumulated to 0.2% of TSP, and in an in vitro rumen digestion assay, γ-gliadin-δ-zein was more resistant to microbial degradation than Rubisco. Additionally, although it did not form protein bodies, a γ-gliadin-GFP fusion protein accumulated to much higher levels, 7% of TSP, than a recombinant protein comprised of an ER localization signal fused to GFP in tobacco. Based on our results, we conclude that γ-gliadin-δ-zein is a potential candidate protein to use for enhancing methionine levels in plants and for improving rumen stability of forage protein. γ-gliadin fusion proteins may provide a general platform for increasing the accumulation of recombinant proteins in transgenic plants. PMID:25659597

  8. Greenhouse (III): Gas-Exchange and Seed-to-Seed Experiments on the Russian Space Station MIR and Earth-grown, Ethylene-Treated Wheat Plants

    NASA Technical Reports Server (NTRS)

    Campbell, William F.; Bingham, Gail; Carman, John; Bubenheim, David; Levinskikh, Margarita; Sytchev, Vladimir N.; Podolsky, Igor B.; Chernova, Lola; Nefodova, Yelena

    2001-01-01

    The Mir Space Station provided an outstanding opportunity to study long-term plant responses when exposed to a microgravity environment. Furthermore, if plants can be grown to maturity in a microgravity environment, they might be used in future bioregenerative life-support systems (BLSS). The primary objective of the Greenhouse experiment onboard Mir was to grow Super Dwarf and Apogee wheat through complete life cycles in microgravity; i.e., from seed-to-seed-to-seed. Additional objectives were to study chemical, biochemical, and structural changes in plant tissues as well as photosynthesis, respiration, and transpiration (evaporation of water from plants). Another major objective was to evaluate the suitability clothe facilities on Mir for advanced research with plants. The Greenhouse experiment was conducted in the Russian/Bulgarian plant growth chamber, the Svet, to which the United States added instrumentation systems to monitor changes in CO2 and water vapor caused by the plants (with four infrared gas analyzers monitoring air entering and leaving two small plastic chambers). In addition, the US instrumentation also monitored O2; air, leaf (IR), cabin pressure; photon flux; and substrate temperature and substrate moisture (16 probes in the root module). Facility modifications were first performed during the summer of 1995 during Mir 19, which began after STS-72 left Mir. Plant development was monitored by daily observations and some photographs.

  9. Evaluation of variations in CO2 gas exchange in the atmosphere of the BTLSS with plants grown in a conveyor mode on the soil-like substrate

    NASA Astrophysics Data System (ADS)

    Velichko, Vladimir; Tikhomirov, Alexander A.; Tikhomirova, Natalia; Ushakova, Sofya

    2016-07-01

    The soil-like substrate (SLS) included in the bioregenerative life support system (BLSS) exerts a substantial effect on its gas exchange. This effect is determined by the non-uniform rate of organic matter degradation in the SLS, on the one hand, and by the variable intensity of photosynthesis of the plants grown on it, on the other. The purpose of this study was to compare CO2 variations in the atmosphere of the higher plants - SLS system at different intervals in uneven-aged higher plant conveyers. The study showed that CO2 concentration could reach and exceed the levels of atmospheric carbon dioxide acceptable for humans (over 1%) even when the conveyer interval was rather short. CO2 variations in the atmosphere of the higher plants - SLS system were determined not only by the frequency of adding plant waste to the SLS and the mass of the waste but also by the amount of the harvested actively photosynthesizing plant biomass. At the same time, no significant differences were found in the mineral and production components between the plants in different experiments. Results of the study can be used to optimize the conveyor interval and the associated effectiveness of mineralization of the plant waste added to the SLS and to stabilize the CO2 gas exchange. This study was carried out in the IBP SB RAS and supported by the grant of the Russian Science Foundation (Project No. 14-14-00599).

  10. Detection of carbon nanotubes in plant roots through microwave-induced heating

    NASA Astrophysics Data System (ADS)

    Irin, Fahmida; Shrestha, Babina; Canas, Jaclyn; Saed, Mohammad; Green, Micah

    2012-02-01

    We demonstrate a novel technique for quantitative detection of CNTs in biological samples by utilizing the thermal response of CNTs under microwave irradiation. In particular, rapid heating of CNTs due to microwave absorption was employed to quantify the amount of CNTs present in alfalfa plant roots. Alfalfa roots were prepared by injecting a known amount of CNTs (single walled and multi walled) and exposed to 30-50 W microwave power to generate calibration curves (temperature rise vs. CNT mass). These calibration curves serve as a characterization tool to determine the unknown amount of CNTs absorbed by alfalfa plant roots grown in CNT-laden soil with superior accuracy and sensitivity. Moreover, the threshold for detectable CNT concentration is much lower than common analytical methods of detecting nanomaterials, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. Considering the lack of effective detection methods for CNT uptake in plants, this method is not only unique but also practical, as it addresses a major problem in the field of nanotoxicology risk assessment.

  11. The Effect of Sludge Application-to-Planting Interval on the Number of Coliforms Recovered from Vegetables Grown on Sludge-Amended Soils

    NASA Astrophysics Data System (ADS)

    Ngole, Veronica M.

    Studies were carried out to determine whether there is any difference in the health risk involved in growing carrots and spinach on sludge-amended soils when a 90-day sludge application-to-planting interval and sludge application-to-harvest intervals are used for further pathogen reduction. The health risk was determined by enumerating the Most Probable Number (MPN) of Faecal Coliform (FC) recovered from both vegetables and identifying the different types of enteric bacteria recovered at harvest. The spinach and carrots were grown on four different soil types unto which a 3 year old sludge (type 1 sludge) and three month old sludge (type 2 sludge) had been separately applied at different rates. Two sludge application-to-planting and sludge application-to-harvest interval were used. A higher number of FC were recovered from carrots (1.5 log10 MPN/10 g-1.8 log10 MPN/10 g) than spinach (< 1.5 log10 MPN/10 g) grown on same soil type with identical type of sludge applied at the same rate. More FC was recovered when a 0±3 day sludge application-to-planting interval was used as opposed to a 90 day sludge application-to-planting interval. Soil type, sludge age and sludge application rate affected the amount of FC recovered. The implications of these results on the specification of time interval in Regulations guiding the growth of vegetables on sludge-amended soil are discussed.

  12. Plant growth and metal distribution in tissues of Prosopis juliflora-velutina grown on chromium contaminated soil in the presence of Glomus deserticola

    PubMed Central

    Arias, Jack A.; Peralta-Videa, Jose R.; Ellzey, Joanne T.; Viveros, Marian N.; Ren, Minghua; Mokgalaka-Matlala, Ntebogeng S.; Castillo-Michel, Hiram; Gardea-Torresdey, Jorge L.

    2015-01-01

    Arbuscular mycorrhizal fungi have been known to increase metal uptake in plants. In this study, mesquite (Prosopis juliflora-velutina) inoculated with Glomus deserticola or amended with EDTA were grown for 30 days in soil containing Cr(III) or Cr(VI) at 0, 40, 80, and 160 mg kg−1. Total amylase activity (TAA) was monitored as a stress indicator. Element concentrations and distribution in tissue were determined using ICP-OES, electron scanning microprobe, and TEM. Inoculated Cr(VI) treated plants had 21% and 30% more Cr than uninoculated and EDTA treated roots, respectively, at 80 mg Cr kg−1 treatment. In the case of Cr(III), EDTA produced the highest Cr accumulation in roots. TAA was higher in inoculated plants grown with Cr(III) at 80 and 160 mg kg−1 and Cr(VI) at 40 and 160 mg kg−1. The X-ray mapping showed higher metal concentrations in the vascular system of inoculated plants and the TEM micrographs demonstrated the presence of G. deserticola in roots. PMID:20795657

  13. Evaluation of the metabolic fate of munitions material (TNT & RDX) in plant systems and initial assessment of material interaction with plant genetic material. Validation of the metabolic fate of munitions materials (TNT, RDX) in mature crops

    SciTech Connect

    Fellows, R.J.; Harvey, S.D.; Cataldo, D.A.

    1995-09-01

    The goals of this effort were to confirm and expand data related to the behavior and impacts of munitions residues upon human food chain components. Plant species employed included corn (Zea mays), alfalfa (Medicago sativa). spinach (Spinacea oleraceae), and carrot (Daucus carota). Plants were grown from seed to maturity (70 to 120 days) in a low-fertility soil (Burbank) amended with either {sup 14}C-TNT or {sup 14}C-RDX at which time they were harvested and analyzed for munitions uptake, partitioning, and chemical form of the munition or munition-metabolite. All four of the plant species used in this study accumulated the {sup 14}C-TNT- and RDX-derived label. The carrot, alfalfa, and corn demonstrated a higher percentage of label retained in the roots (62, 73, and 83% respectively). The spinach contained less activity in its root (36%) but also contained the highest TNT specific activity observed (>4600 jig TNT equivalents/g dry wt.). The specific uptake values of RDX for the spinach and alfalfa were comparable to those previously reported for wheat and bean (314 to 590 {mu}g RDX-equivalents/g dry wt. respectively). An exception to this may be the carrot where the specific activity was found to exceed 4200 {mu}g RDX-equivalents/g dry wt. in the shoot. The total accumulation of TNT by the plants ranged from 1.24% for the spinach to 2.34% for the carrot. The RDX plants ranging from 15% for the spinach to 37% for the carrot. There was no identifiable TNT or amino dinitrotoluene (ADNT) isomers present in the plants however, the parent RDX compound was found at significant levels in the shoot of alfalfa (> 1 80 {mu}g/g) and corn (>18 {mu}g/g).

  14. Enteric methane emission, diet digestibility, and nitrogen excretion from beef heifers fed sainfoin or alfalfa.

    PubMed

    Chung, Y-H; Mc Geough, E J; Acharya, S; McAllister, T A; McGinn, S M; Harstad, O M; Beauchemin, K A

    2013-10-01

    Effects of plant-bound condensed tannin (CT)-containing sainfoin vs. CT-free alfalfa (or low-CT alfalfa-sainfoin mixture), plant stage of maturity, and their interaction on enteric methane (CH4) emissions, diet digestibility, and N excretion were studied, using 8 ruminally cannulated beef heifers in 2 sequential short-term experiments (Exp. 1 and 2). In Exp. 1, first growth legumes were harvested daily and offered fresh to heifers. Heifers were assigned to 100% sainfoin or 80% alfalfa:20% sainfoin (as-fed basis). Responses were measured at early (late vegetative to early bud; stage 2 to 3) and late (early flower; stage 5) stage of maturity. In Exp. 2, the same legumes were harvested from second growth (late bud; stage 4) and offered to heifers as hay; 100% sainfoin or 100% alfalfa. In both experiments, heifers were fed once daily at 1× maintenance. When fed as fresh forage (Exp. 1), sainfoin, compared with the alfalfa-sainfoin blend, had greater digestibility of OM (74.7 vs. 70.9%; P = 0.02), yet tended to have lower CP digestibility (73.2 vs. 77.1%; P = 0.059). There was no difference between fresh legumes for CH4 emissions [25.9 g/kg DMI ± 4.02 SE; 8.5% of gross energy intake (GEI) ± 1.26 SE; or 36.8 g/kg digested OM ± 1.75 SE]. The fresh legumes were more digestible at early, rather than at late, maturity and, consequently, enteric CH4 (27.4 vs. 24.4 g/kg DMI; P < 0.004; 8.9 vs. 8.1% GEI; P < 0.008) was greater at early, rather than at later, growth. When fed as hay (Exp. 2), sainfoin, compared with alfalfa, had greater digestibility of OM (60.5 vs. 50.3%; P = 0.007), lower digestibility of CP (64.2 vs. 68.8%; P = 0.004), yet there was no difference between the legume hays for CH4 emissions (22.4 g/kg DMI ± 1.29 SD and 7.1% GEI ± 0.40 SD). However, on the basis of OM digested, CH4 emissions were lower for sainfoin than alfalfa hay (44.3 vs. 59.0 g/kg; P = 0.008). Percentage of total N excretion in urine was less for sainfoin compared with alfalfa, both for

  15. Characterization of plant-growth-promoting effects and concurrent promotion of heavy metal accumulation in the tissues of the plants grown in the polluted soil by Burkholderia strain LD-11.

    PubMed

    Huang, Gui-Hai; Tian, Hui-Hui; Liu, Hai-Ying; Fan, Xian-Wei; Liang, Yu; Li, You-Zhi

    2013-01-01

    Plant-growth-promoting (PGP) bacteria especially with the resistance to multiple heavy metals are helpful to phytoremediation. Further development of PGP bacteria is very necessary because of the extreme diversity of plants, soils, and heavy metal pollution. A Burkholderia sp. strain, numbered LD-11, was isolated, which showed resistances to multiple heavy metals and antibiotics. It can produce indole-3-acetic acid, 1-aminocyclopropane-1-carboxylic acid deaminase and siderophores. Inoculation with the LD-11 improved germination of seeds of the investigated vegetable plants in the presence of Cu, promoted elongation of roots and hypocotyledonary axes, enhanced the dry weights of the plants grown in the soils polluted with Cu and/or Pb, and increased activity of the soil urease and the rhizobacteria diversity. Inoculation with the LD-11 significantly enhanced Cu and/or Pb accumulation especially in the roots of the plants grown in the polluted soils. Notably, LD-11 could produce siderophores in the presence of Cu. Conclusively, the PGP effects and concurrent heavy metal accumulation in the plant tissues results from combined effects of the above-mentioned multiple factors. Cu is an important element that represses production of the siderophore by the bacteria. Phytoremediation by synergistic use of the investigated plants and the bacterial strain LD-11 is a phytoextraction process. PMID:23819291

  16. Identification of Molecular Markers Associated with Verticillium Wilt Resistance in Alfalfa (Medicago Sativa L.) Using High-Resolution Melting

    PubMed Central

    Zhang, Tiejun; Yu, Long-Xi; McCord, Per; Miller, David; Bhamidimarri, Suresh; Johnson, David; Monteros, Maria J.; Ho, Julie; Reisen, Peter; Samac, Deborah A.

    2014-01-01

    Verticillium wilt, caused by the soilborne fungus, Verticillium alfalfae, is one of the most serious diseases of alfalfa (Medicago sativa L.) worldwide. To identify loci associated with resistance to Verticillium wilt, a bulk segregant analysis was conducted in susceptible or resistant pools constructed from 13 synthetic alfalfa populations, followed by association mapping in two F1 populations consisted of 352 individuals. Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were used for genotyping. Phenotyping was done by manual inoculation of the pathogen to replicated cloned plants of each individual and disease severity was scored using a standard scale. Marker-trait association was analyzed by TASSEL. Seventeen SNP markers significantly associated with Verticillium wilt resistance were identified and they were located on chromosomes 1, 2, 4, 7 and 8. SNP markers identified on chromosomes 2, 4 and 7 co-locate with regions of Verticillium wilt resistance loci reported in M. truncatula. Additional markers identified on chromosomes 1 and 8 located the regions where no Verticillium resistance locus has been reported. This study highlights the value of SNP genotyping by high resolution melting to identify the disease resistance loci in tetraploid alfalfa. With further validation, the markers identified in this study could be used for improving resistance to Verticillium wilt in alfalfa breeding programs. PMID:25536106

  17. Tissue Cultures Derived from Ineffective Root Nodules of Alfalfa 1

    PubMed Central

    Vance, Carroll P.; Johnson, Lois E. B.; Boylan, Kristin L. M.

    1984-01-01

    Callus tissue cultures were developed from apical meristem regions of tumor-like ineffective root nodules of alfalfa. Callus growth was a function of tissue source and hormone composition and concentration. Callus derived from ineffective nodules also were shown not to contain Rhizobium meliloti. Glutamate dehydrogenase, glutamine synthetase, glutamate synthase, glutamate oxaloacetate transaminase and phosphoenolpyruvate carboxylase activities were present in callus cultures and in the respective nodule source used for callus induction. The mean specific activity of all enzymes evaluated was higher in callus cultures than in ineffective nodules. Quantitative but not qualitative differences in enzyme activities were evident between ineffective nodules and callus derived from these nodules. Tissue cultures derived from ineffective nodules may provide a model system to evaluate host plant-Rhizobium interactions. Images Fig. 1 PMID:16663985

  18. Phosphorylation of alfalfa mosaic virus movement protein in vivo.

    PubMed

    Kim, Bong-Suk; Halk, Edward L; Merlo, Donald J; Nelson, Steven E; Loesch-Fries, L Sue

    2014-07-01

    The 32-kDa movement protein, P3, of alfalfa mosaic virus (AMV) is essential for cell-to-cell spread of the virus in plants. P3 shares many properties with other virus movement proteins (MPs); however, it is not known if P3 is posttranslationally modified by phosphorylation, which is important for the function of other MPs. When expressed in Nicotiana tabacum, P3 accumulated primarily in the cell walls of older leaves or in the cytosol of younger leaves. When expressed in Pischia pastoris, P3 accumulated primarily in a soluble form. Metabolic labeling indicated that a portion of P3 was phosphorylated in both tobacco and yeast, suggesting that phosphorylation regulates the function of this protein as it does for other virus MPs. PMID:24435161

  19. ECOLOGICAL RISK ASSESSMENT OF ALFALFA (MEDICAGO VARIA L.) GENETICLALY ENGINEERED TO EXPRESS A HUMAN METALLOTHIONEIN (HMT) GENE

    EPA Science Inventory

    The objectives of these studies were two-fold: (1) to determine efficacy of low and high expression hMT gene constructs by assessing accumulation of Cu in shoots of parental and transgenic plants of alfalfa (Medicago varia L.) exposed to different concentrations of CuSO4 by addit...

  20. Spissistilus festinus reovirus: a novel, unassigned species of the family Reoviridae infecting the three-cornered alfalfa hopper

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A complex set of double stranded RNAs (dsRNA) were isolated from threecornered alfalfa hopper (Spissistilus festinus), a plant-feeding hemipteran insect pest. A subset of these dsRNAs constitute the genome of a novel, unassigned reovirus designated as Spissistilus festinus reovirus (SpFRV). Phylogen...

  1. Behavioral response of Lygus hesperus to conspecifics and headspace volatiles of alfalfa in a y-tube olfactometer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The western tarnished plant bug, Lygus hesperus Knight, feeds and develops on a variety of weeds in the spring, with later generations moving to alfalfa and cotton where severe damage to reproductive structures can occur. A synthetic attractant for monitoring or mass-trapping L. hesperus, or the ide...

  2. Use of GIS maps in assessing the role of alfalfa in the epidemiology of xylellae diseases in California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grape and almond are planted throughout much of California. Both crops are susceptible to diseases caused by Xylella fastidiosa. Within California’s Central Valley, the green sharpshooter (Draeculacephala minerva) is a key vector. This insect is often found in large numbers in cultivated alfalfa ...

  3. Mentha canadensis L., a subtropical plant can withstand first few fall frost when grown in northern climate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Japanese cornmint (Mentha canadensis L.) is a subtropical essential oil crop grown in Asia and South America. The essential oil of Japanese cornmint is the only commercial source for production of natural crystalline menthol, an important aromatic agent used in various industrial applications. The ...

  4. Development of greenhouse grown onion transplants and effect of plant density and fertilizer rate on marketable yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Greenhouse grown onion (Allium cepa L.) transplants may have potential for use in production systems, but how they respond to cultural practices needs clarification. Seedlings of ‘Candy' and ‘Texas Grano 1015Y' were raised in a greenhouse. ‘Candy' seedlings were heavier than ‘Texas Grano 1015Y' se...

  5. Yield and quality of field-grown Celosia and Gomphrena everlasting cut flowers at four planting densities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field-grown cut flowers dried for market could provide a high-value crop selection for semiarid regions, but data on field production of flowers are limited. We conducted a field study on replicated 1.5-m2 plots to evaluate flower yield and quality characteristics of Gomphrena globosa, G. haageana,...

  6. Growth, reproductive phenology and yield responses of a potential biofuel plant, Jatropha curcas grown under projected 2050 levels of elevated CO2.

    PubMed

    Kumar, Sumit; Chaitanya, Bharatula S K; Ghatty, Sreenivas; Reddy, Attipalli R

    2014-11-01

    Jatropha (Jatropha curcas) is a non-edible oil producing plant which is being advocated as an alternative biofuel energy resource. Its ability to grow in diverse soil conditions and minimal requirements of essential agronomical inputs compared with other oilseed crops makes it viable for cost-effective advanced biofuel production. We designed a study to investigate the effects of elevated carbon dioxide concentration ([CO(2)]) (550 ppm) on the growth, reproductive development, source-sink relationships, fruit and seed yield of J. curcas. We report, for the first time that elevated CO(2) significantly influences reproductive characteristics of Jatropha and improve its fruit and seed yields. Net photosynthetic rate of Jatropha was 50% higher in plants grown in elevated CO(2) compared with field and ambient CO(2) -grown plants. The study also revealed that elevated CO(2) atmosphere significantly increased female to male flower ratio, above ground biomass and carbon sequestration potential in Jatropha (24 kg carbon per tree) after 1 year. Our data demonstrate that J. curcas was able to sustain enhanced rate of photosynthesis in elevated CO(2) conditions as it had sufficient sink strength to balance the increased biomass yields. Our study also elucidates that the economically important traits including fruit and seed yield in elevated CO(2) conditions were significantly high in J. curcas that holds great promise as a potential biofuel tree species for the future high CO(2) world. PMID:24655305

  7. The ALFALFA HI Absorption Pilot Project

    NASA Astrophysics Data System (ADS)

    Macdonald, Erin; Darling, J.; ALFALFA Team

    2009-01-01

    We present the results of a pilot project to search for HI 21 cm absorption in the Arecibo Legacy Fast Arecibo L-Band Feed Array (ALFALFA) Survey. This project is the first to conduct a "blind" wide-area search for HI absorption in the local universe. The search covered 517.0 deg2 spanning 10.9h < α < 14.95h and +7.7o < δ < +16.3o. The ALFALFA survey covers -650 km s-1 < cz < 17,500 km s-1, for a Δz = 0.054 along each line of sight (11% of the cz span is lost to radio frequency interference and Galactic HI emission). There are 243 sources toward which all damped Lyα systems (N(HI) > 2x1020 cm-2) could be detected, and 3282 sources toward which N(HI) > 2x1021 cm-2 columns could be detected (assuming 100 K spin temperature, 30 km s-1 line width, and unity filling factor). We performed Green Bank Telescope follow-up observations of 13 possible absorption lines and the 250 strong sources (> 220 mJy) in our survey region. One previously known intrinsic HI absorption line in UGC 6081 was re-detected, but no additional lines were identified in the survey region. Nevertheless, this pilot project demonstrates the value and feasibility of large-area absorption line searches commensal with emission line surveys. An absorption line search of the entire 7000 deg2 ALFALFA Survey is a worthwhile undertaking, not only to identify HI absorption systems in the local universe, but to measure the fraction of HI gas not accounted for by emission line surveys. ALFALFA is a legacy survey at the Arecibo Observatory supported by NAIC and NSF.

  8. Prediction of phytoavailability of trace metals to plants: Comparison between chemical extractions and soil-grown radish

    NASA Astrophysics Data System (ADS)

    Baraud, Fabienne; Leleyter, Lydia

    2012-08-01

    One of the major routes of human exposure to toxic metals is the consumption of vegetables grown on contaminated soils. Radishes were grown in three different soils (kitchen garden, agricultural and industrial soils), presenting various contamination levels. A sequential extraction procedure was compared with EDTA and HCl simple extractions methods in order to predict the metals phytoavailabilty to radish. The analysis of the results shows that the simple HCl and sequential chemical extractions bring complementary results, since HCl is correlated in the phytoavailability of Cd, Mn and Zn, whereas the sequential extraction is correlated in the phytoavailability of Cr, Fe, Mn, Ni. EDTA simple extraction brings here less interesting results than the two other tested extractions.

  9. Alfalfa containing the glyphosate-tolerant trait has no effect on feed intake, milk composition, or milk production of dairy cattle.

    PubMed

    Combs, D K; Hartnell, G F

    2008-02-01

    The objective of this experiment was to assess if feeding glyphosate-tolerant alfalfa affects feed intake, milk composition, or milk production of dairy cows. One alfalfa (Medicago sativa), variety expressing the CP4 EPSPS protein and grown in southeastern Washington State was harvested at the late vegetative stage as hay. Three commercial conventional varieties of alfalfa hay of similar nutrient composition and harvested in the same geographic region were fed to cows as controls. The commercial hays were selected to be similar in crude protein [18% of dry matter (DM)] and neutral detergent fiber (40% of DM) to the glyphosate-tolerant hay. Sixteen multiparous Holstein cows were fed diets containing alfalfa hay (39.7% of diet DM) from either the glyphosate-tolerant alfalfa, or 1 of the 3 conventional varieties. Diets contained at least 15.7% crude protein and 29% neutral detergent fiber. Experimental design was a replicated 4 x 4 Latin square. Periods were 28 d and feed intake, milk yield, and milk composition were summarized over the last 14 d of each period. Daily milk yield (38.0 kg) and 4% fat-corrected milk (34.7 kg) were not affected by treatment. Milk fat (3.44%) and milk true protein (2.98%) were also not affected by source of hay. Milk lactose (4.72%) and soldis-not-fat (8.5%) did not differ due to treatment. Dry matter intake was similar across treatments (24.4 kg/d). These results are consistent with data from feeding trials with other glyphosate-tolerant crops and previously reported compositional comparisons of glyphosate-tolerant alfalfa with controls. Milk production, milk composition, feed intake, and feed efficiency were not affected by feeding diets that contained nearly 40% glyphosate-tolerant alfalfa hay to lactating dairy cows. PMID:18218755

  10. Health risk assessment of polycyclic aromatic hydrocarbons and heavy metals via dietary intake of vegetables grown in the vicinity of thermal power plants.

    PubMed

    Khillare, P S; Jyethi, Darpa Saurav; Sarkar, Sayantan

    2012-05-01

    Six different vegetables grown in the vicinity of three thermal power plants and a background site in Delhi, India were analyzed for 16 priority polycyclic aromatic hydrocarbons (PAHs) and 7 heavy metals (Cd, Cu, Cr, Ni, Zn, Fe and Mn). Annual mean concentrations of PAHs and all metals were found to be significantly higher (ANOVA, p<0.001) at power plant sites as compared to the background site. Higher abundances of coal tracer PAHs such as Phen, Anth, Flan, Pyr and Chry in power plant vegetables suggested possible impacts of coal combustion emissions. Higher ratios of polluted sample-to-background sample of vegetables were found especially for Cr, Cd, Ni and Zn. Spinach and radish showed greater accumulation of PAHs and metals on a mass basis at the power plant sites while vegetables belonging to the gourd family showed highest relative enrichment. Power plant samples showed 184-475% greater metal pollution index (MPI) values as compared to the background location while health risk indices (HRI) for Cd and Ni exceeded the safe limit for most vegetables. Incremental lifetime cancer risk (ILCR) assessment showed that up to 58 excess cancer cases are likely in Delhi for lifetime ingestion exposure to PAHs at their observed concentrations. PMID:22326808

  11. Characterization of Feeding Injuries Caused by Ceresa nigripectus Remes Lenicov (Hemiptera: Membracidae) on Alfalfa Stems.

    PubMed

    Grosso, T P; Mercado, M I; Ponessa, G I; Conci, L R; Virla, E G

    2016-04-01

    Piercing-sucking insects cause mechanical and physiological injury to plants. Ceresa nigripectus Remes Lenicov is a pest of alfalfa in subtropical regions of South America and a carrier of the ArAWB phytoplasma. The aim of this study was to determine the feeding habits of this treehopper and to describe the effects of the feeding injuries on stem vascular tissues in alfalfa. Adults and nymphs of C. nigripectus inserted their stylets repeatedly girdling the stem. One week after feeding, alfalfa stems exhibited numerous feeding canals with salivary deposits, most of which reached the phloem. Two weeks after feeding, cortex and phloem cells next to the salivary sheath collapsed, mature tracheal elements became sparse and appeared with an increased cross-section area, and phenolic compounds increased in cells and cell walls compared to undamaged plants. Three weeks after feeding, an annular callus, formed by abnormal cell division and hypertrophy of preexisting cortex and vascular cambium cells, appeared immediately above the stem girdle. Parenchyma cells from the outer layers of the callus differentiated to form secondary anomalous amphicribal bundles in the wound. The aerial parts above the stem girdle eventually withered and died. PMID:26830435

  12. Migration of Fusarium verticillioides between inoculated and non-inoculated ears of field-grown corn plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consequences of Fusarium verticillioides colonization of corn kernels may be plant disease and/or mycotoxin production. Plant disease may reduce crop production and mycotoxins may cause harmful, and often fatal, effects on humans and animals. Understanding migration patterns of F. verticillioides ...

  13. Metabolomic profiling from leaves and roots of tomato (Solanumlycopersicum L.) plants grown under nitrogen, phosphorus or potassium-deficient condition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nitrogen (N), phosphorus (P) and potassium (K) are essential macronutrients that are required in large quantities by growing plants. Deficiency of N, P or K can strongly affect metabolites in plant tissues. However, specific metabolic network responses to nutrient deficiencies are not well-defined. ...

  14. Expression of a fungal ferulic acid esterase in alfalfa modifies cell wall digestibility

    PubMed Central

    2014-01-01

    Background Alfalfa (Medicago sativa) is an important forage crop in North America owing to its high biomass production, perennial nature and ability to fix nitrogen. Feruloyl esterase (EC 3.1.1.73) hydrolyzes ester linkages in plant cell walls and has the potential to further improve alfalfa as biomass for biofuel production. Results In this study, faeB [GenBank:AJ309807] was synthesized at GenScript and sub-cloned into a novel pEACH vector containing different signaling peptides to target type B ferulic acid esterase (FAEB) proteins to the apoplast, chloroplast, endoplasmic reticulum and vacuole. Four constructs harboring faeB were transiently expressed in Nicotiana leaves, with FAEB accumulating at high levels in all target sites, except chloroplast. Stable transformed lines of alfalfa were subsequently obtained using Agrobacterium tumefaciens (LBA4404). Out of 136 transgenic plants regenerated, 18 independent lines exhibited FAEB activity. Subsequent in vitro digestibility and Fourier transformed infrared spectroscopy (FTIR) analysis of FAEB-expressing lines showed that they possessed modified cell wall morphology and composition with a reduction in ester linkages and elevated lignin content. Consequently, they were more recalcitrant to digestion by mixed ruminal microorganisms. Interestingly, delignification by alkaline peroxide treatment followed by exposure to a commercial cellulase mixture resulted in higher glucose release from transgenic lines as compared to the control line. Conclusion Modifying cell wall crosslinking has the potential to lower recalcitrance of holocellulose, but also exhibited unintended consequences on alfalfa cell wall digestibility due to elevated lignin content. The combination of efficient delignification treatment (alkaline peroxide) and transgenic esterase activity complement each other towards efficient and effective digestion of transgenic lines. PMID:24650274

  15. Inhibitory potential of pure isoflavonoids, red clover, and alfalfa extracts on hemoglobin glycosylation

    PubMed Central

    Hosseini, Mohsen; Asgary, Sedigheh; Najafi, Somayeh

    2015-01-01

    BACKGROUND Non-enzymatic glycosylation of hemoglobin is complications of diabetes. Antioxidant system imbalance can result in the emergence of free radicals’ destructive effects in the long-term. Red clover (Trifolium pratense L.) and alfalfa (Medicago sativa L.) contain isoflavonoids and have antioxidant activity. This experimental study evaluated the inhibitory activity of pure isoflavonoids (daidzein and genistein), red clover and alfalfa extracts on hemoglobin glycosylation. METHODS This study was performed in Iran. Stock solution of hydroalcoholic extracts of red clover and alfalfa in concentrations of 1 and 10 g/100 ml and stock solution of daidzein and genistein in concentrations of 250 ng, 500 ng, 25 µg and 250 µg/100 ml were prepared as case groups. Control group was without hydroalcoholic extracts of plants and pure isoflavonoids. All experiments were performed in triplicate. Hemoglobin was prepared and antioxidant activities were investigated to estimate degree of nonenzymatic hemoglobin glycosylation. RESULTS There was no significantly difference between used extracts (extract of red clover and alfalfa) and control of the hemoglobin glycosylation but using daidzein (P = 0.046, 0.029 and 0.021, respectively) and genistein (P = 0.034, 0.036 and 0.028) significantly inhibited (P < 0.050) this reaction in 25 µg/100 ml, 250 and 500 ng/100 ml concentrations when compared to control. in 25 µg/100 ml, 250 ng and 500 ng/100 ml concentrations percentage of inhibition were 32, 80 and 74.5% respectively with used of daidzein and were 21, 83 and 76% respectively with consumption of genistein. CONCLUSION According to decrease of glycation of hemoglobin with isoflavonoids, two used plant in this study containing isoflavonoid may be useful on diabetes. PMID:26405442

  16. Alfalfa forage and seed crop tolerance to flumioxazin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weed control is an important component of producing high quality and high yielding alfalfa seed and forage. Flumioxazin was evaluated for weed control in alfalfa forage and seed production in 2007 and 2008 in Washington State. Flumioxazin applied at 0.14 and 0.28 kg ai/ha plus paraquat in February t...

  17. Reductions in potash for last-year alfalfa production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Applying the correct amount of potassium (K) fertilizer is critical for alfalfa yield and stand persistence; however, excess K fertilizer will decrease profits and increase the risk of milk fever when alfalfa is fed to fresh cows. Stand persistence is often not a major concern in the last year of al...

  18. Environmental stability of stem cell wall traits in alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concentration of stem cell wall constituents in alfalfa, Medicago sativa L., herbage can affect dry matter intake and energy availability in dairy and beef production systems and impact energy conversion efficiency when alfalfa is used to produce biofuels. Stem Klason lignin, glucose, xylose, an...

  19. Predicting fertilizer nitrogen response in corn following alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Correct prediction and application of alfalfa nitrogen (N) credits to first-year corn can reduce fertilizer N costs for growers, reduce over-application of N, and reduce the potential for water contamination. For decades, researchers have found that first-year corn following alfalfa often requires n...

  20. Alfalfa: Potential For New Feed and Biofuel - USDFRC Research Update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa hay is a major crop supporting U.S ruminant livestock industry, particularly dairy. Several cellulosic feedstocks will be needed to meet current ethanol production goals. Alfalfa has considerable potential as a feedstock for production of ethanol and other industrial materials because of i...

  1. ALFALFA YIELD AND QUALITY RELATIONSHIPS WITHIN INDIVIDUAL HARVESTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extensive cutting management research has documented the effects of date and frequency of harvest on alfalfa (Medicago sativa L.) forage yield and quality. Information is lacking, however, on the change in quality relative to yield that occurs as alfalfa matures within cuttings over the whole growi...

  2. Does K affect N response of corn after alfalfa?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rising potassium (K) fertilizer prices in recent years have made it imperative for farmers to apply optimum K rates for alfalfa-corn rotations. However, little is understood about the effect of excess K applied to alfalfa on the subsequent corn crop's grain and silage yield. Furthermore, relatively ...

  3. Harvest management impacts on stem quality in alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The concentration of stem cell wall constituents in alfalfa, Medicago sativa L., herbage can affect dry matter intake and energy availability in dairy and beef production systems and impact energy conversion efficiency when alfalfa is used to produce biofuels. Stem total cell wall concentration, Kla...

  4. Satellite images reveal patterns in crop rotations with alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crops that follow alfalfa in rotation usually benefit from: i) reduced nitrogen (N) requirement from fertilizer or manure; ii) increased yield potential than when following other crops; and iii) reduced weed, insect, and disease pressure. Although benefits of alfalfa in crop rotations often depend o...

  5. Inoculant effects on alfalfa silage: fermentation products and nutritive value

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of fourteen microbial inoculants on the fermentation and nutritive value of alfalfa silages was studied under laboratory conditions. First (477 g dry matter (DM)/kg) and second cuttings (393 g DM /kg) of a second year alfalfa stand were ensiled in two experiments. In both experiments, alf...

  6. CYTOGENETIC INVESTIGATIONS OF NON-DORMANT ALFALFA GERMPLASM SOURCES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The combined techniques of chromosome C-banding, image analysis, and cluster analysis were utilized to compare the four historically distinct non-dormant alfalfa germplasm sources of tetraploid alfalfa (Medicago sativa ssp. sativa). Cytogenetic analyses revealed polymorphisms for heterochromatic DN...

  7. Elimination of toxicity from diets containing alfalfa seeds.

    PubMed

    Malinow, M R; McLaughlin, P; Bardana, E J; Craig, S

    1984-07-01

    Cynomolgus macaques were fed autoclaved alfalfa seeds for up to 1 yr. There were no humoral signs of a syndrome resembling systemic lupus erythematosus. The data are in contrast to those previously reported in monkeys fed raw alfalfa seeds, in which a systemic lupus erythematosus-like syndrome was induced in a shorter interval. The autoclaved seeds retained antihypercholesterolaemic effects. PMID:6540232

  8. Complete genome sequence of the alfalfa latent virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa latent virus (ALV) is a member of the carlavirus group and occurs symptomlessly in alfalfa (Medicago sativa). In the US it is prevalent in Nebraska and Wisconsin. The virus is recognized as a strain of Pea streak virus (PeSV) So far, no complete genomic sequence of PSV or ALV is availab...

  9. Alfalfa Biomass Germplasms: SFP Detection and Transcriptome Analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Advances in alfalfa [Medicago sativa (L.) subsp. sativa] breeding, molecular genetics, and genomics have been slow because this crop is an allogamous autotetraploid (2n = 4x = 32) with complex polysomic inheritance. Increasing cellulose and decreasing lignin in alfalfa stem cell walls would improve ...

  10. Does Alfalfa-Hay NDFD Matter in a Dairy TMR?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three feeding trials were conducted to study the effect of alfalfa-hay in vitro neutral detergent fiber digestibility (IVNDFD, 48-hour laboratory incubation in rumen fluid) on Holstein dairy cow performance. Treatments (Lh, Ll, Hh, and Hl) included four alfalfa hays selected for relatively low-(L) o...

  11. Potassium management during the rotation from alfalfa to corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High potassium (K) fertilizer prices in recent years have made it imperative for growers to apply optimum K rates to alfalfa (Medicago sativa L.). Current University of Minnesota fertilizer guidelines in the Corn Belt do not change for the last production year when alfalfa stand persistence is not a...

  12. 'Don' a Diploid Falcata Alfalfa for Western US Rangelands

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Don' (Reg. No. CV-______, PI _______) a diploid falcata alfalfa (Medicago sativa subsp falcata L.) developed by the Forage and Range Research Laboratory in Logan, Utah, in cooperation with the Utah Agricultural Experiment Station, Utah State University. Recent interest in falcata alfalfa has been ...

  13. Intended release and actual retention of alfalfa leafcutting bees (Hymenoptera: Megachilidae) for pollination in commercial alfalfa seed fields.

    PubMed

    Pitts-Singer, Theresa L

    2013-04-01

    Low, medium, and high stocking densities (15,000; 30,000; and 45,000-50,000 bees per acre, respectively) of Megachile rotundata (F.) (Hymenoptera: Megachilidae), the alfalfa leafcutting bee, were released over 4 yr in three research plots of Utah alfalfa, Medicago sativa L. (Fabaceae), planted at seed-production rates. A low percentage of bees (46-79% of released) survived the incubation and field-emergence processes; of those bees, the number of females that established at the nesting sites was 25-100%. Of the three field sites, one site consistently retained more females and produced more completed nests than the other sites, all of which usually had poor female establishment and progeny production. In addition, floral resources were depleted over time, but many flowers remained unvisited over the season. Nest production decreased over time, as numbers of flowers and female bees declined. Significant positive relationships were found between the intended stocking densities and 1) the number of females that actually survived incubation and field emergence and 2) the number of females that established nests. The number of females that established nests was positively affected by the number of females that survived to emerge in the field. The percentage of females that established was not significantly affected by the intended number of released bees, countering a prediction that the release of fewer bees would allow more females to establish nests and achieve high reproductive success. For growers, it may be more frugal to use modest numbers of M. rotundata for pollination, because many of the bees at medium and high stocking densities do not nest in grower-provided bee boards. PMID:23786042

  14. Opportunities exist to improve alfalfa and manure nitrogen crediting in corn following alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A survey of Minnesota growers was conducted to determine adoption of extension N rate guidelines for fertilizer and manure for first- and second-year corn (Zea mays L.) following alfalfa (Medicago sativa L.) (AC and ACC, respectively) during 2009 to 2011. There were 421 and 273 valid responses for A...

  15. Comparative Analysis Of {sup 226}Ra Soil-To-Plant Transfer In Cabbage Grown In Various Regions

    SciTech Connect

    Madruga, M. J.; Carvalho, F. P.; Silva, L.; Gouveia, J.

    2008-08-07

    The transfer of {sup 226}Ra from soil to cabbage was compared amongst regions, namely the surroundings of Urgeirica uranium milling tailings (GE), regions with past uranium mining activities (GN1), and regions with no uranium mining activities and no uranium deposits (GN2). Results show a slight increase of the concentration ratio values at low radium concentration in soils. Statistical analysis of the mean {sup 226}Ra activity concentrations in soil and cabbage for the three regions was carried out. The comparison of {sup 226}Ra activity concentrations in soils indicated no difference (p>0.05), between GE and GN2 and significant differences (p<0.05) between GE and GN1 and between GN1 and GN2. Similar statistical results were obtained for {sup 226}Ra activity concentrations in cabbage from the same regions. It was concluded that radium Concentration Ratio (CR) for cabbage grown in the region of the main uranium milling site (GE) is of the same order of magnitude of CR in cabagge grown in background regions (GN2). However, {sup 226}Ra CR was higher in cabagge from the region with past uranium mining activities (GN1)

  16. Alfalfa variety development. Minnesota Agripower Project, Task II research report

    SciTech Connect

    Lamb, J.F.S.; Samac, D.A.; Sheaffer, C.C.

    1997-10-30

    This report briefly summarizes preliminary results from crossbreeding alfalfa to develop desirable characteristics for a dedicated biomass feed stock. The varieties development is part of a larger project which includes preparation and gasification of the alfalfa stems for energy production, and use of the co-product alfalfa leaves in livestock feed. The desired alfalfa traits include winter hardiness, resistance to major pathogens, resistance to foliar disease complexes, many thick, tall, solid, non-lodging stems with high lignin content, delayed flowering, and high quality leaves retained through harvest. Currently no alfalfa varieties meet these criteria. Three crosses were made using old European varieties, with thick stems, and modern resistant varieties. The crossbreeds showed some resistance to diseases, but increased resistance is needed to maximize leaf and steam yield. 1 tab.

  17. Molecular cloning and characterization of three isoprenyl diphosphate synthase genes from alfalfa.

    PubMed

    Sun, Yan; Long, Ruicai; Kang, Junmei; Zhang, Tiejun; Zhang, Ze; Zhou, He; Yang, Qingchuan

    2013-02-01

    Isoprenoid is the precursor for the biosynthesis of saponins, abscisic acid, gibberellins, chlorophylls and many other products in plants. Saponins are an important group of bioactive plant natural products. The alfalfa (Medicago sativa L.) saponins are glycosides of different triterpene aglycones and possess many biological activities. We isolated three genes (MsFPPS, MsGPPS and MsGGPPS) encoding isoprenyl diphosphate synthases (IDS) from alfalfa via a homology-based PCR approach. The enzyme activity assay of purified recombined MsFPPS and MsGGPPS expressed in Escherichia coli indicated that they all had IDS activity. Expression analysis of the three genes in different alfalfa tissues using real time PCR displayed that they were expressed in all tissues although they had a different expression patterns. MsFPPS and MsGPS displayed a significant increase in transcript level in response to methyl jasmonate, but the transcript level of MsGGPPS decreased obviously. To elucidate the functions of the three IDSs, their overexpression driven by a constitutive cauliflower mosaic virus-35S promoter in tobacco plants was applied and analyzed. The T(0) transgenic plants of MsFPPS showed high levels of squalene content when compared with control. However, no differences were detected in T(0) transgenic plants of MsGPPS and MsGGPPS. In addition, the overexpression of MsFPPS induced senescence response in transgenic plant leaves. This result may indicate that MsFPPS performs a role not only in phytosterol and triterpene biosynthesis, but also in growth regulation. PMID:23238915

  18. Glutamine nitrogen and ammonium nitrogen supplied as a nitrogen source is not converted into nitrate nitrogen of plant tissues of hydroponically grown pak-choi (Brassica chinensis L.).

    PubMed

    Wang, H-J; Wu, L-H; Tao, Q-N; Miller, D D; Welch, R M

    2009-03-01

    Many vegetables, especially leafy vegetables, accumulate NO(-) (3)-N in their edible portions. High nitrate levels in vegetables constitute a health hazard, such as cancers and blue baby syndrome. The aim of this study was to determine if (1) ammonium nitrogen (NH(+) (4)-N) and glutamine-nitrogen (Gln-N) absorbed by plant roots is converted into nitrate-nitrogen of pak-choi (Brassica chinensis L.) tissues, and (2) if nitrate-nitrogen (NO(-) (3)-N) accumulation and concentration of pak-choi tissues linearly increase with increasing NO(-) (3)-N supply when grown in nutrient solution. In experiment 1, 4 different nitrogen treatments (no nitrogen, NH(+) (4)-N, Gln-N, and NO(-) (3)-N) with equal total N concentrations in treatments with added N were applied under sterile nutrient medium culture conditions. In experiment 2, 5 concentrations of N (from 0 to 48 mM), supplied as NO(-) (3)-N in the nutrient solution, were tested. The results showed that Gln-N and NH(+) (4)-N added to the nutrient media were not converted into nitrate-nitrogen of plant tissues. Also, NO(-) (3)-N accumulation in the pak-choi tissues was the highest when plants were supplied 24 mM NO(-) (3)-N in the media. The NO(-) (3)-N concentration in plant tissues was quadratically correlated to the NO(-) (3)-N concentration supplied in the nutrient solution. PMID:19323774

  19. Effect of 1-naphthaleneacetic acid on organic acid exudation by the roots of white lupin plants grown under phosphorus-deficient conditions.

    PubMed

    Gómez, Diego A; Carpena, Ramón O

    2014-09-15

    The effect of NAA (1-naphthaleneacetic acid) on organic acid exudation in white lupin plants grown under phosphorus deficiency was investigated. Plants were sampled periodically for collecting of organic acids (citrate, malate, succinate), and also were used to study the effect on proton extrusion and release of Na(+), K(+), Ca(2+) and Mg(2+). The tissues were later processed to quantify the organic acids in tissues, the phosphorus content and the effects on plant biomass. The exogenous addition of NAA led to an increase in organic acid exudation, but this response was not proportional to the concentration of the dose applied, noticing the largest increments with NAA 10(-8)M. In contrast the increase in root weight was proportional to the dose applied, which shows that with higher doses the roots produced are not of proteoid type. Proton extrusion and the release of cations were related to the NAA dose, the first was proportional to the dose applied and the second inversely proportional. Regarding the analysis of tissues, the results of citrate and phosphorus content in shoots show that the overall status of these parts are the main responsible of the organic acids exuded. NAA served as an enhancer of the organic acid exudation that occurs under phosphorus deficient conditions, with a response that depends on the dose applied, not only in its magnitude, but also in the mechanism of action of the plant hormone. PMID:25046756

  20. Matrix effects for calcium and potassium K-X-rays, in fenugreek plants grown in iron rich soils.

    PubMed

    Deep, Kanan; Rao, Preeti; Bansal, Himani; Mittal, Raj

    2014-08-01

    The present work comprises the matrix effects study of the plant system (plant and soil) for macronutrients Ca and K with elevated levels of iron in the soil. The earlier derived matrix effect terms from fundamental relations of intensities of analyte and substrate elements with basic atomic and experimental setup parameters had led to iterative determination of enhanced elements rather than avoiding their enhancement. The relations also facilitated the evaluations of absorption for close Z interfering constituents (like Ca and K) in samples of a lot of particular category with interpolation of matrix terms with elemental amounts. The process has already been employed successfully for potato, radish, rice and maize plants. On similar lines, the observed prominent change in interpolation parameters for the plants in the present experiment serves as a tool to check the toxicity/contamination of the growing medium. PMID:24709609

  1. High incidence of plant growth-stimulating bacteria associated with the rhizosphere of wheat grown on salinated soil in Uzbekistan.

    PubMed

    Egamberdieva, Dilfuza; Kamilova, Faina; Validov, Shamil; Gafurova, Laziza; Kucharova, Zulfiya; Lugtenberg, Ben

    2008-01-01

    Soil salinization is increasing steadily in many parts of the world and causes major problems for plant productivity. Under these stress conditions, root-associated beneficial bacteria can help improve plant growth and nutrition. In this study, salt-tolerant bacteria from the rhizosphere of Uzbek wheat with potentially beneficial traits were isolated and characterized. Eight strains which initially positively affect the growth of wheat plants in vitro were investigated in detail. All eight strains are salt tolerant and have some of the following plant growth-beneficial properties: production of auxin, HCN, lipase or protease and wheat growth promotion. Using sequencing of part of the 16S rDNA, the eight new isolates were identified as Acinetobacter (two strains), Pseudomonas aeruginosa, Staphylococcus saprophyticus, Bacillus cereus, Enterobacter hormaechei, Pantoae agglomerans and Alcaligenes faecalis. All these strains are potential human pathogens. Possible reasons for why these bacteria present in the rhizosphere and establish there are discussed. PMID:18211262

  2. Host density drives spatial variation in parasitism of the alfalfa weevil, Hypera postica, across dryland and irrigated alfalfa cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biological control against the alfalfa weevil, Hypera postica (Gyllenhal), a destructive pest of alfalfa, has resulted in the establishment of nine hymenpoteran parasitoid species in the USA. Despite widespread redistribution of a number of these species, there remains little post-release data on th...

  3. Occurrence of transgenic feral alfalfa (Medicago sativa subsp. sativa L.) in alfalfa seed production areas in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetically-engineered glyphosate-resistant alfalfa (Medicago sativa subsp. sativa) was commercialized in 2011. The potential risk of transgene dispersal into the environment is not clearly understood for alfalfa, a perennial crop that is cross-pollinated by insects. We gathered data on feral and tr...

  4. MOLECULAR DNA MARKERS UTILIZED TO DISCERN ALFALFA FALL DORMANCY CHECK CULTIVARS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa cultivars are difficult to distinguish based upon morphological traits. Only a few morphological traits have been used to describe alfalfa. Molecular markers especially simple sequence repeats (SSR) have not been utilized in alfalfa to characterize alfalfa cultivars. This study was conduct...

  5. Challenges and opportunities for improved N management in corn following alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With some exceptions, the alfalfa nitrogen (N) credit usually eliminates the need for manure N and/or fertilizer N to economically optimize yield of the first corn crop following alfalfa. Alfalfa also can provide nearly one-half or more of the N requirement for the second corn crop following alfalfa...

  6. Soil and water warming accelerates phenology and down-regulation of leaf photosynthesis of rice plants grown under free-air CO2 enrichment (FACE).

    PubMed

    Adachi, Minaco; Hasegawa, Toshihiro; Fukayama, Hiroshi; Tokida, Takeshi; Sakai, Hidemitsu; Matsunami, Toshinori; Nakamura, Hirofumi; Sameshima, Ryoji; Okada, Masumi

    2014-02-01

    To enable prediction of future rice production in a changing climate, we need to understand the interactive effects of temperature and elevated [CO2] (E[CO2]). We therefore examined if the effect of E[CO2] on the light-saturated leaf photosynthetic rate (Asat) was affected by soil and water temperature (NT, normal; ET, elevated) under open-field conditions at the rice free-air CO2 enrichment (FACE) facility in Shizukuishi, Japan, in 2007 and 2008. Season-long E[CO2] (+200 µmol mol(-1)) increased Asat by 26%, when averaged over two years, temperature regimes and growth stages. The effect of ET (+2°C) on Asat was not significant at active tillering and heading, but became negative and significant at mid-grain filling; Asat in E[CO2]-ET was higher than in ambient [CO2] (A[CO2])-NT by only 4%. Photosynthetic down-regulation at E[CO2] also became apparent at mid-grain filling; Asat compared at the same [CO2] in the leaf cuvette was significantly lower in plants grown in E[CO2] than in those grown in A[CO2]. The additive effects of E[CO2] and ET decreased Asat by 23% compared with that of A[CO2]-NT plants. Although total crop nitrogen (N) uptake was increased by ET, N allocation to the leaves and to Rubisco was reduced under ET and E[CO2] at mid-grain filling, which resulted in a significant decrease (32%) in the maximum rate of ribulose-1,5-bisphosphate carboxylation on a leaf area basis. Because the change in N allocation was associated with the accelerated phenology in E[CO2]-ET plants, we conclude that soil and water warming accelerates photosynthetic down-regulation at E[CO2]. PMID:24406632

  7. Soil and Water Warming Accelerates Phenology and Down-Regulation of Leaf Photosynthesis of Rice Plants Grown Under Free-Air CO2 Enrichment (FACE)

    PubMed Central

    Adachi, Minaco; Hasegawa, Toshihiro; Fukayama, Hiroshi; Tokida, Takeshi; Sakai, Hidemitsu; Matsunami, Toshinori; Nakamura, Hirofumi; Sameshima, Ryoji; Okada, Masumi

    2014-01-01

    To enable prediction of future rice production in a changing climate, we need to understand the interactive effects of temperature and elevated [CO2] (E[CO2]). We therefore examined if the effect of E[CO2] on the light-saturated leaf photosynthetic rate (Asat) was affected by soil and water temperature (NT, normal; ET, elevated) under open-field conditions at the rice free-air CO2 enrichment (FACE) facility in Shizukuishi, Japan, in 2007 and 2008. Season-long E[CO2] (+200 µmol mol−1) increased Asat by 26%, when averaged over two years, temperature regimes and growth stages. The effect of ET (+2°C) on Asat was not significant at active tillering and heading, but became negative and significant at mid-grain filling; Asat in E[CO2]–ET was higher than in ambient [CO2] (A[CO2])–NT by only 4%. Photosynthetic down-regulation at E[CO2] also became apparent at mid-grain filling; Asat compared at the same [CO2] in the leaf cuvette was significantly lower in plants grown in E[CO2] than in those grown in A[CO2]. The additive effects of E[CO2] and ET decreased Asat by 23% compared with that of A[CO2]–NT plants. Although total crop nitrogen (N) uptake was increased by ET, N allocation to the leaves and to Rubisco was reduced under ET and E[CO2] at mid-grain filling, which resulted in a significant decrease (32%) in the maximum rate of ribulose-1,5-bisphosphate carboxylation on a leaf area basis. Because the change in N allocation was associated with the accelerated phenology in E[CO2]–ET plants, we conclude that soil and water warming accelerates photosynthetic down-regulation at E[CO2]. PMID:24406632

  8. Photosynthesis is induced in rice plants that associate with arbuscular mycorrhizal fungi and are grown under arsenate and arsenite stress.

    PubMed

    de Andrade, Sara Adrian Lopez; Domingues, Adilson Pereira; Mazzafera, Paulo

    2015-09-01

    The metalloid arsenic (As) increases in agricultural soils because of anthropogenic activities and may have phytotoxic effects depending on the available concentrations. Plant performance can be improved by arbuscular mycorrhiza (AM) association under challenging conditions, such as those caused by excessive soil As levels. In this study, the influence of AM on CO2 assimilation, chlorophyll a fluorescence, SPAD-chlorophyll contents and plant growth was investigated in rice plants exposed to arsenate (AsV) or arsenite (AsIII) and inoculated or not with Rhizophagus irregularis. Under AsV and AsIII exposure, AM rice plants had greater biomass accumulation and relative chlorophyll content, increased water-use efficiency, higher carbon assimilation rate and higher stomatal conductance and transpiration rates than non-AM rice plants did. Chlorophyll a fluorescence analysis revealed significant differences in the response of AM-associated and -non-associated plants to As. Mycorrhization increased the maximum and actual quantum yields of photosystem II and the electron transport rate, maintaining higher values even under As exposure. Apart from the negative effects of AsV and AsIII on the photosynthetic rates and PSII efficiency in rice leaves, taken together, these results indicate that AM is able to sustain higher rice photosynthesis efficiency even under elevated As concentrations, especially when As is present as AsV. PMID:25935603

  9. Influence of salicylic acid on rubisco and rubisco activase in tobacco plant grown under sodium chloride in vitro

    PubMed Central

    Lee, So Young; Damodaran, Puthanveettil Narayanankutty; Roh, Kwang Soo

    2014-01-01

    The present study was designed to evaluate the influence of salicylic acid (SA) on the growth of salt stress (sodium chloride) induced in tobacco plants. In addition, quantification of rubisco and rubisco activase contents of the plants was also determined in treatments with the control, 10−4 mM SA, 50 mM NaCl, 100 mM NaCl, 150 mM NaCl, SA + 50 mM NaCl, SA + 100 mM NaCl and SA + 150 mM NaCl, respectively after in vitro culture for 5 weeks. The growth of the tobacco plant decreased in 50 mM and 100 mM NaCl when not treated with SA. However, the growth was accelerated by SA, and the growth retardation caused by NaCl was improved by SA. The content of rubisco was improved by SA only in plants treated with 50 mM NaCl, and the activity of rubisco was increased by SA resulting in the decreased effect of NaCl, but only in 50 mM NaCl treated plants. The content of rubisco activase decreased due to NaCl, and SA did not improve the effect caused by NaCl. The activity of rubisco activase was increased by SA resulting in decreased activity caused by NaCl, but increased effect by SA was not recovered to the level of NaCl untreated plants. The activity of rubisco and rubisco activase, which decreased due to denaturing agents, did not demonstrate significant improvement when compared to the control. PMID:25313276

  10. Influence of salicylic acid on rubisco and rubisco activase in tobacco plant grown under sodium chloride in vitro.

    PubMed

    Lee, So Young; Damodaran, Puthanveettil Narayanankutty; Roh, Kwang Soo

    2014-11-01

    The present study was designed to evaluate the influence of salicylic acid (SA) on the growth of salt stress (sodium chloride) induced in tobacco plants. In addition, quantification of rubisco and rubisco activase contents of the plants was also determined in treatments with the control, 10(-4) mM SA, 50 mM NaCl, 100 mM NaCl, 150 mM NaCl, SA + 50 mM NaCl, SA + 100 mM NaCl and SA + 150 mM NaCl, respectively after in vitro culture for 5 weeks. The growth of the tobacco plant decreased in 50 mM and 100 mM NaCl when not treated with SA. However, the growth was accelerated by SA, and the growth retardation caused by NaCl was improved by SA. The content of rubisco was improved by SA only in plants treated with 50 mM NaCl, and the activity of rubisco was increased by SA resulting in the decreased effect of NaCl, but only in 50 mM NaCl treated plants. The content of rubisco activase decreased due to NaCl, and SA did not improve the effect caused by NaCl. The activity of rubisco activase was increased by SA resulting in decreased activity caused by NaCl, but increased effect by SA was not recovered to the level of NaCl untreated plants. The activity of rubisco and rubisco activase, which decreased due to denaturing agents, did not demonstrate significant improvement when compared to the control. PMID:25313276

  11. Combined effects of CO2 enrichment, diurnal light levels and water stress on foliar metabolites of potato plants grown in naturally sunlit controlled environment chambers.

    PubMed

    Barnaby, Jinyoung Y; Fleisher, David; Reddy, Vangimalla; Sicher, Richard

    2015-02-01

    Experiments were conducted in outdoor, naturally sunlit, soil-plant-atmosphere research (SPAR) chambers using plants grown in pots. Drought treatments were imposed on potato plants (Solanum tuberosum cv. Kennebec) beginning 10 days after tuber initiation. A total of 23 out of 37 foliar metabolites were affected by drought when measured 11 days after initiating water stress treatments. Compounds that accumulated in response to drought were hexoses, polyols, branched chain amino acids (BCAAs) and aromatic amino acids, such as proline. Conversely, leaf starch, alanine, aspartate and several organic acids involved in respiratory metabolism decreased with drought. Depending upon harvest date, a maximum of 12 and 17 foliar metabolites also responded to either CO2 enrichment or diurnal treatments, respectively. In addition, about 20% of the measured metabolites in potato leaflets were simultaneously affected by drought, CO2 enrichment and diurnal factors combined. This group contained BCAAs, hexoses, leaf starch and malate. Polyols and proline accumulated in response to water stress but did not vary diurnally. Water stress also amplified diurnal variations of hexoses and starch in comparison to control samples. Consequently, specific drought responsive metabolites in potato leaflets were dramatically affected by daily changes of photosynthetic carbon metabolism. PMID:24888746

  12. Metabolic profiling reveals altered nitrogen nutrient regimes have diverse effects on the metabolism of hydroponically-grown tomato (Solanum lycopersicum) plants.

    PubMed

    Urbanczyk-Wochniak, Ewa; Fernie, Alisdair R

    2005-01-01

    The role of inorganic nitrogen assimilation in the production of amino acids is one of the most important biochemical processes in plants. For this reason, a detailed broad-range characterization of the metabolic response of tomato (Solanum lycopersicum) leaves to the alteration of nitrate level was performed. Tomato plants were grown hydroponically in liquid culture under three different nitrate regimes: saturated (8 mM NO3-), replete (4 mM NO3-) and deficient (0.4 mM NO3-). All treatments were performed under varied light intensity, with leaf samples being collected after 7, 14, and 21 d. In addition, the short-term response (after 1, 24, 48, and 94 h) to varying nutrient status was evaluated at the higher light intensity. GC-MS analysis of the levels of amino acids, tricarboxylic acid cycle intermediates, sugars, sugar alcohols, and representative compounds of secondary metabolism revealed substantial changes under the various growth regimes applied. The data presented here suggest that nitrate nutrition has wide-ranging effects on plant leaf metabolism with nitrate deficiency resulting in decreases in many amino and organic acids and increases in the level of several carbohydrates and phosphoesters, as well as a handful of secondary metabolites. These results are compared with previously reported transcript profiles of altered nitrogen regimes and discussed within the context of current models of carbon nitrogen interaction. PMID:15596475

  13. Plant density and N fertilizer rate on yield and nutrient content of onion developed from greenhouse grown transplants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Onions (Allium cepa L.) can be established from seed or transplants. The latter planting material can be dormant or actively growing when transplanted to the field. Onion transplants can be produced in a greenhouse, but additional information is needed regarding the cultural requirements for these...

  14. Biological effects and biochemical studies of tomato plants grown from seeds exposed for a long time at the MIR station

    NASA Astrophysics Data System (ADS)

    Nechitailo, G.; Yurov, S.; Kuznetsov, A.; Kapitanov, A.

    Experiments at orbital space stations were carried out with seeds of various plants -- welsh onion arabidopsis wheat pea maize barley tomato etc The results of these experiments showed some discrepancy concerning germinating capacity presence of chromosome aberrations and other parameters After short-term space flights most of plants did not exhibit any irreversible changes But prolongation of space flights to over one year leads to practically complete loss of the germinating capacity in for example Arabidopsis thaliana and Crepis capillaries The level of recessive mutations increased more than 3-fold as compared to the control variants after exposure of seeds during 840 days The objects studied in the experiments described here are tomato plants obtained from seeds carried for 6 years at the station MIR According to the results of the experiments the germinating capacity of the seeds was 32 versus 60 in the control The germination of the seeds began only on the 14-15 th days in the control -- on the 5 th day In the process of ontogenesis the level of mutations revealed in the experimental variants made up to 18 as compared to the 8 in the control After 6 years of exposure under space flight conditions practically all seeds lost their germinating capacity Most viable were seeds of wheat and tomato Biochemical analysis of tomato plants of the second generation produced from seeds exposed for a long time under space flight conditions was carried out The results of the analysis demonstrated an increased

  15. In vitro ruminal degradation and synthesis of protein on fractions extracted from alfalfa hay and silage.

    PubMed

    Peltekova, V D; Broderick, G A

    1996-04-01

    Net release of degraded N as NH3 and total AA plus microbial protein synthesis, quantified from incorporation of 15NH3 into microbial protein, was used to estimate the rate and extent of in vitro degradation of protein fractions isolated from alfalfa hay and silage. Seven proteins (casein, alfalfa hay, alfalfa silage, extracts from alfalfa hay and silage, and residues from alfalfa hay and silage) were studied. Results from (NH4)2SO4 and SDS-PAGE fractionations suggested that soluble proteins in alfalfa hay and silage differed in susceptibility to proteolytic attack. Although the net release of NH3 plus total AA N from alfalfa silage and alfalfa silage extract was twofold greater than that from alfalfa hay and alfalfa hay extract, net microbial protein synthesis on alfalfa hay and alfalfa hay extract was 33 and 43% greater. Despite greater NPN content in alfalfa silage, protein degradation rate and estimated escape were similar for intact alfalfa hay (0.103/h and 43%) and silage (0.067/h and 43%). This result might be explained by the less efficient microbial utilization of silage NPN, greater protozoal numbers on hay, greater soluble true protein in hay, or differences in molecular mass and stability of soluble proteins in hay versus silage. Use of a two-compartment model, based on water-soluble and insoluble CP fractions assumed to pass with the liquid and solid phases, respectively, yielded RUP estimates for alfalfa hay and silage that were similar to NRC estimates. PMID:8744226

  16. Effects of AN Alfalfa (medicago Sativa) Buffer Strip on Leached δ15NNITRATE Values: Implications for Management of Hydrologic N Losses

    NASA Astrophysics Data System (ADS)

    Kelley, C. J.; Keller, C. K.; Smith, J. L.; Evans, R. D.; Harlow, B.

    2011-12-01

    Buffer strips are commonly used to decrease agricultural runoff with the objective of limiting sediment and agrochemicals fluxes to surface waters. The objective of this study was to determine the effects of an alfalfa buffer strip on the magnitude and source(s) of leached nitrate from a dryland agricultural field. Previous research at the Cook Agronomy Farm has inferred two sources of nitrate in tile drain discharge, a high-discharge-season (January through May) synthetic fertilizer source, and a low-discharge-season (June through December) soil organic nitrogen source. This study examines how a change in management strategy and crop species alters the low discharge season nitrate source. In the spring of 2006 an alfalfa buffer strip approximately 20 m wide was planted running approximately north-south in the lowland portion of a 12 ha tile-drained field bordering a ditch that drains into Missouri Flat Creek. Three-year (2003 through 2005) average NO3--N flux prior to the planting of the alfalfa buffer strip was ~0.40 kg ha-1 year-1. After planting, the three-year (2006 through 2008) average NO3--N flux was ~0.38 kg ha-1 year-1. The lack of evident buffer-strip influence on the fluxes may be due in part to the large variation in precipitation amounts and timing that control water flows through the system. Three-year average δ15Nnitrate values for the tile drain pre and post planting of the alfalfa buffer strip were 6.9 ± 1.1 % and 4.2 ± 0.9 % respectively. We hypothesize that the significant difference indicates that the alfalfa strip affects the source of leached nitrate. Before planting the alfalfa buffer strip, the interpreted source of nitrate was mineralization of soil organic nitrogen from non-N2 fixing crops (spring and summer wheat varieties). After planting the alfalfa buffer strip, the source of nitrate was interpreted to be a mixture of mineralized soil organic nitrogen from N2 fixing alfalfa and non-N2 fixing crops. Further work is needed to test

  17. Phytotoxicity of three plant-based biodiesels, unmodified castor oil, and Diesel fuel to alfalfa (Medicago sativa L.), lettuce (Lactuca sativa L.), radish (Raphanus sativus), and wheatgrass (Triticum aestivum).

    PubMed

    Bamgbose, Ifeoluwa; Anderson, Todd A

    2015-12-01

    The wide use of plant-based oils and their derivatives, in particular biodiesel, have increased extensively over the past decade to help alleviate demand for petroleum products and improve the greenhouse gas emissions profile of the transportation sector. Biodiesel is regarded as a clean burning alternative fuel produced from livestock feeds and various vegetable oils. Although in theory these animal and/or plant derived fuels should have less environmental impact in soil based on their simplified composition relative to Diesel, they pose an environmental risk like Diesel at high concentrations when disposed. The aim of the present study was to ascertain the phytotoxicity of three different plant-derived biodiesels relative to conventional Diesel. For phytotoxicological analysis, we used seeds of four crop plants, Medicago sativa, Lactuca sativa, Raphanus sativus, and Triticum aestivum to analyze the germination of seeds in contaminated soil samples. The toxicological experiment was conducted with two different soil textures: sandy loam soil and silt loam soil. The studied plant-based biodiesels were safflower methyl-ester, castor methyl ester, and castor ethyl-ester. Biodiesel toxicity was more evident at high concentrations, affecting the germination and survival of small-seeded plants to a greater extent. Tolerance of plants to the biodiesels varied between plant species and soil textures. With the exception of R. sativus, all plant species were affected and exhibited some sensitivity to the fuels, such as delayed seedling emergence and slow germination (average=10 days) at high soil concentrations (0.85% for Diesel and 1.76% for the biodiesels). Tolerance of plants to soil contamination had a species-specific nature, and on average, decreased in the following order: Raphanus sativus (0-20%)>Triticum aestivum (10-40%) ≥ Medicago sativa> Lactuca sativa (80-100%). Thus, we conclude that there is some phytotoxicity associated with plant-based biodiesels. Further

  18. Uptake of copper and cerium by alfalfa, lettuce and cucumber exposed to nCeO2 and nCuO through the foliage or the roots: Impacts on food quality, physiological and agronomical parameters

    NASA Astrophysics Data System (ADS)

    Hong, Jie

    Nanotechnology is increasingly attracting attention not only for its variety of applications in modern life, but for the potential negative effects that nanomaterials (NMs) can cause in the environment and human health. Studies have shown varied effects of engineered nanoparticles (ENPs) on plants; however, most of these studies focused on the interaction of NPs with plants at root level. The increasing production and use of NPs have also increased the atmospheric amounts of NPs, which could be taken up by plants through their leaves. Cucumbers (Cucumis sativus L.) are broad leaf plants commonly grown both commercially and in home vegetable gardens that can be easily impacted by atmospheric NPs. However, there is limited information about the potential effects of these atmospheric NPs on cucumber. This research was aimed to determine (I) the possible uptake and translocation of cerium (Ce) by cucumber plants exposed to nCeO 2 (cerium dioxide nanoparticles, nanoceria) through the foliage, (II) the impacts of the NPs on physiological parameters of the plants and the effects on the nutritional value and quality of the fruits, and (III) the effects of seven copper compounds/nanoparticles applied to the growth medium of lettuce (Lactuca sativa) and alfalfa (Medicago sativa). For aim I, 15 day-old hydroponically grown cucumber plants were exposed to nCeO2, either as powder at 0.98 and 2.94 g/m3 or suspensions at 20, 40, 80, 160, 320 mg/l. Ce uptake was analyzed by using inductively coupled plasma-optical emission spectroscopy (ICP-OES) and transmission electron microscope (TEM). The activity of three stress enzymes was measured by UV/Vis. Ce was detected in all cucumber tissues and TEM images showed the presence of Ce in roots. Results suggested nCeO2 penetrated plants through leaves and moved to other plant parts. The biochemical assays showed nCeO2 also modified stress enzyme activities. For aim II, 15 day-old soil grown cucumber plants were foliar treated, separately

  19. Uptake of copper and cerium by alfalfa, lettuce and cucumber exposed to nCeO2 and nCuO through the foliage or the roots: Impacts on food quality, physiological and agronomical parameters

    NASA Astrophysics Data System (ADS)

    Hong, Jie

    Nanotechnology is increasingly attracting attention not only for its variety of applications in modern life, but for the potential negative effects that nanomaterials (NMs) can cause in the environment and human health. Studies have shown varied effects of engineered nanoparticles (ENPs) on plants; however, most of these studies focused on the interaction of NPs with plants at root level. The increasing production and use of NPs have also increased the atmospheric amounts of NPs, which could be taken up by plants through their leaves. Cucumbers (Cucumis sativus L.) are broad leaf plants commonly grown both commercially and in home vegetable gardens that can be easily impacted by atmospheric NPs. However, there is limited information about the potential effects of these atmospheric NPs on cucumber. This research was aimed to determine (I) the possible uptake and translocation of cerium (Ce) by cucumber plants exposed to nCeO 2 (cerium dioxide nanoparticles, nanoceria) through the foliage, (II) the impacts of the NPs on physiological parameters of the plants and the effects on the nutritional value and quality of the fruits, and (III) the effects of seven copper compounds/nanoparticles applied to the growth medium of lettuce (Lactuca sativa) and alfalfa (Medicago sativa). For aim I, 15 day-old hydroponically grown cucumber plants were exposed to nCeO2, either as powder at 0.98 and 2.94 g/m3 or suspensions at 20, 40, 80, 160, 320 mg/l. Ce uptake was analyzed by using inductively coupled plasma-optical emission spectroscopy (ICP-OES) and transmission electron microscope (TEM). The activity of three stress enzymes was measured by UV/Vis. Ce was detected in all cucumber tissues and TEM images showed the presence of Ce in roots. Results suggested nCeO2 penetrated plants through leaves and moved to other plant parts. The biochemical assays showed nCeO2 also modified stress enzyme activities. For aim II, 15 day-old soil grown cucumber plants were foliar treated, separately

  20. Regulation of UVR8 photoreceptor dimer/monomer photo-equilibrium in Arabidopsis plants grown under photoperiodic conditions.

    PubMed

    Findlay, Kirsten M W; Jenkins, Gareth I

    2016-08-01

    The UV RESISTANCE LOCUS 8 (UVR8) photoreceptor specifically mediates photomorphogenic responses to UV-B. Photoreception induces dissociation of dimeric UVR8 into monomers to initiate responses. However, the regulation of dimer/monomer status in plants growing under photoperiodic conditions has not been examined. Here we show that UVR8 establishes a dimer/monomer photo-equilibrium in plants growing in diurnal photoperiods in both controlled environments and natural daylight. The photo-equilibrium is determined by the relative rates of photoreception and dark-reversion to the dimer. Experiments with mutants in REPRESSOR OF UV-B PHOTOMORPHOGENESIS 1 (RUP1) and RUP2 show that these proteins are crucial in regulating the photo-equilibrium because they promote reversion to the dimer. In plants growing in daylight, the UVR8 photo-equilibrium is most strongly correlated with low ambient fluence rates of UV-B (up to 1.5 μmol m(-2) s(-1) ), rather than higher fluence rates or the amount of photosynthetically active radiation. In addition, the rate of reversion of monomer to dimer is reduced at lower temperatures, promoting an increase in the relative level of monomer at approximately 8-10 °C. Thus, UVR8 does not behave like a simple UV-B switch under photoperiodic growth conditions but establishes a dimer/monomer photo-equilibrium that is regulated by UV-B and also influenced by temperature. PMID:26864532

  1. Bioaccumulation and distribution of heavy metals in Maize, Oat and Sorghum Plants, grown in industrially polluted region

    NASA Astrophysics Data System (ADS)

    Angelova, Violina; Ivanova, Radka; Ivanov, Krasimir

    2010-05-01

    The uptake of heavy metals (Cd, Pb and Zn) by maize, oat and sorghum plants cultivated, under field conditions, in industrially polluted soils was studied. The experimental plots were situated at different distances (0.1, 2.0 and 15.0 km) from the source of pollution - the Non-Ferrous Metal Works near Plovdiv, Bulgaria. On reaching commercial ripeness the crops were gathered and the contents of heavy metals in their different parts - roots, stems, leaves and grains, were determined after dry ashing. The quantitative measurements were carried out with ICP. A clearly distinguished species peculiarity existed in the accumulation of heavy metals in the vegetative and reproductive organs of the studied crops. Sorghum plants accumulated larger heavy metal quantities compared to maize and oat plants, as the major part of heavy metals was retained by roots and a very small part was translocated to epigeous parts. The studied crops may be considered as metal-tolerant crops and may be cultivated on soils which are low, medium or highly contaminated with lead, zinc and cadmium, as they do not show a tendency of accumulating these elements in epigeous parts and grains above the maximum permissible concentrations. The possible use of aboveground mass and grains for animal food guarantees the economic expedience upon the selection of these crops. Acknowledgment: This work is supported by the Bulgarian Ministry of Education, Project DO-02-87/08.

  2. Characterization of Epiphytic Bacterial Communities from Grapes, Leaves, Bark and Soil of Grapevine Plants Grown, and Their Relations

    PubMed Central

    Martins, Guilherme; Lauga, Béatrice; Miot-Sertier, Cécile; Mercier, Anne; Lonvaud, Aline; Soulas, Marie-Louise; Soulas, Guy; Masneuf-Pomarède, Isabelle

    2013-01-01

    Despite its importance in plant health and crop quality, the diversity of epiphytic bacteria on grape berries and other plant parts, like leaves and bark, remains poorly described, as does the role of telluric bacteria in plant colonization. In this study, we compare the bacterial community size and structure in vineyard soils, as well as on grapevine bark, leaves and berries. Analyses of culturable bacteria revealed differences in the size and structure of the populations in each ecosystem. The highest bacteria population counts and the greatest diversity of genera were found in soil samples, followed by bark, grapes and leaves. The identification of isolates revealed that some genera – Pseudomonas, Curtobacterium, and Bacillus – were present in all ecosystems, but in different amounts, while others were ecosystem-specific. About 50% of the genera were common to soil and bark, but absent from leaves and grapes. The opposite was also observed: grape and leaf samples presented 50% of genera in common that were absent from trunk and soil. The bacterial community structure analyzed by T-RFLP indicated similarities between the profiles of leaves and grapes, on the one hand, and bark and soil, on the other, reflecting the number of shared T-RFs. The results suggest an interaction between telluric bacterial communities and the epiphytic bacteria present on the different grapevine parts. PMID:24023666

  3. The copper tolerance strategies and the role of antioxidative enzymes in three plant species grown on copper mine.

    PubMed

    Boojar, Massod Mashhadi Akbar; Goodarzi, Faranak

    2007-05-01

    This study was undertaken to identify the strategies and the status of antioxidant enzyme activities involved in three plant species tolerance against Cu-toxicity in copper mine. The following methods were used for evaluations in three wild type species; Datura stramonium, Malva sylvestris and Chenopodium ambrosioides. The level of chlorophyll and the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) by spectrometry, malondialdehyde (MDA) and dityrosine by HPLC and the levels of Cu in tissues and soils by atomic absorption spectrometry (AAS). Analysis showed that total and available copper were at toxic levels for plants growing on contaminated soil (zone 1). However, there were not any visual and conspicuous symptoms of Cu toxicity in plant species. Among three species, excess copper was transferred only into the D. stramonium and C. ambrosioides tissues. The C. ambrosioides accumulated Cu in roots and then in leaves, in which the leaves chloroplasts stored Cu around two times of vacuoles. In D. stramonium most of Cu was accumulated in leaves in which the storage rate in vacuoles and chloroplasts were 42% and 8%, respectively. In zone 1, the chlorophyll levels increased significantly in leaves of C. ambrosioides with respect to the same plant growing on uncontaminated soil (zone 2). There was insignificant decrease in chlorophyll content of D. stramonium leaves, collected from zone 1 with respect to zone 2. The D. stramonium and C. ambrosioides in zone 1, both revealed significant increase in their tissues antioxidant enzyme activities in comparison with the same samples of zone 2. There was significant elevation in oxidative damage biomarkers; MDA and dityrosine, when the aerial parts of D. stramonium in zone 1 were compared with the same parts of zone 2. We concluded that there were different tolerance strategies in studied plant species that protected them against copper toxicity. In M. sylvestris, exclusion of Cu from

  4. Growth and elemental accumulation of plants grown in acidic soil amended with coal fly ash-sewage sludge co-compost

    SciTech Connect

    Wong, J.W.C.; Selvam, A.

    2009-10-15

    A greenhouse experiment was conducted to evaluate the growth and heavy-metal accumulation of Brassica chinensis and Agropyron elongatum in 10 and 25% ash-sludge co-compost (ASC)-amended loamy acidic soil (pH 4.51) at two different application rates: 20% and 40% (v/v). Soil pH increased, whereas electrical conductivity decreased with the amendment of ASC to soil. Bioavailable Cu, Zn, and Mn contents of ASC-amended soil decreased, whereas Ni, Pb, and B contents increased. Concentrations of bioavailable Cu, Zn, and Mn in sludge compost (SC)-amended soils were 5.57, 20.8, and 8.19 mg kg{sup -1}, respectively. These concentrations were significantly lower than those in soil receiving an application rate of 20 or 25% ASC as 2.64, 8.48, and 5.26 mg kg(-1), respectively. Heavy metals and B contents of the composting mass significantly increased with an increase in ASC application rate from 20 to 40% (6.2 to 16.6 mg kg{sup -1} for 10% ASC- and 9.4 to 18.6 mg kg{sup -1} for 25% ASC-amended soil. However, when the ash content in co-compost increased from 10 to 25% during composting, bioavailable heavy-metal contents decreased. However, B contents increased with an increase in ash content. Addition of co-composts increased the dry-weight yield of the plants, and this increase was more obvious as the ash amendment rate in the co-composts and the ASC application rate increased. In case of B. chinensis, the biomass of 2.84 g/plant for 40% application of 25% ASC was significantly higher than SC (0.352 g/plant), which was 40% application of 10% ASC (0.434 g/plant) treatments. However, in A. elongatum, the differences between biomass of plants grown with 10% (1.34-1.94 g/ plant) and 25% ASC (2.12-2.21 g/plant) were not significantly different. ASC was favorable in increasing the growth of B. chinensis and A. elongatum. The optimal ash amendment to the sludge composting and ASC application rates were at 25 and 20%, respectively.

  5. In vitro antagonistic activity, plant growth promoting traits and phylogenetic affiliation of rhizobacteria associated with wild plants grown in arid soil

    PubMed Central

    El-Sayed, Wael S.; Akhkha, Abdellah; El-Naggar, Moustafa Y.; Elbadry, Medhat

    2014-01-01

    The role of plant growth-promoting rhizobacteria (PGPR) in adaptation of plants in extreme environments is not yet completely understood. For this study native bacteria were isolated from rhizospeheric arid soils and evaluated for both growth-promoting abilities and antagonistic potential against phytopathogenic fungi and nematodes. The phylogentic affiliation of these representative isolates was also characterized. Rhizobacteria associated with 11 wild plant species from the arid soil of Almadinah Almunawarah, Kingdom of Saudi Arabia (KSA) were investigated. From a total of 531 isolates, only 66 bacterial isolates were selected based on their ability to inhibit Fusarium oxysporum, and Sclerotinia sclerotiorum. The selected isolates were screened in vitro for activities related to plant nutrition and plant growth regulation as well as for antifungal and nematicidal traits. Isolated bacteria were found to exhibit capabilities in fix atmospheric nitrogen, produce ammonia, indoleacetic acid (IAA), siderophores, solubilize phosphate and zinc, and showed an antagonistic potential against some phytopathogenic fungi and one nematode species (Meloidogyne incognita) to various extent. Isolates were ranked by their potential ability to function as PGPR. The 66 isolates were genotyped using amplified rDNA restriction analysis (ARDRA) and 16S rRNA gene sequence analysis. The taxonomic composition of the representative genotypes from both rhizosphere and rhizoplane comprised Bacillus, Enterobacter and Pseudomonas. Out of the 10 genotypes, three strains designated as PHP03, CCP05, and TAP02 might be regarded as novel strains based on their low similarity percentages and high bootstrap values. The present study clearly identified specific traits in the isolated rhizobacteria, which make them good candidates as PGPR and might contribute to plant adaption to arid environments. Application of such results in agricultural fields may improve and enhance plant growth in arid soils

  6. Tomato yellow leaf curl virus infection mitigates the heat stress response of plants grown at high temperatures

    PubMed Central

    Ghandi, Anfoka; Adi, Moshe; Lilia, Fridman; Linoy, Amrani; Or, Rotem; Mikhail, Kolot; Mouhammad, Zeidan; Henryk, Czosnek; Rena, Gorovits

    2016-01-01

    Cultured tomatoes are often exposed to a combination of extreme heat and infection with Tomato yellow leaf curl virus (TYLCV). This stress combination leads to intense disease symptoms and yield losses. The response of TYLCV-susceptible and resistant tomatoes to heat stress together with viral infection was compared. The plant heat-stress response was undermined in TYLCV infected plants. The decline correlated with the down-regulation of heat shock transcription factors (HSFs) HSFA2 and HSFB1, and consequently, of HSF-regulated genes Hsp17, Apx1, Apx2 and Hsp90. We proposed that the weakened heat stress response was due to the decreased capacity of HSFA2 to translocate into the nuclei of infected cells. All the six TYLCV proteins were able to interact with tomato HSFA2 in vitro, moreover, coat protein developed complexes with HSFA2 in nuclei. Capturing of HSFA2 by viral proteins could suppress the transcriptional activation of heat stress response genes. Application of both heat and TYLCV stresses was accompanied by the development of intracellular large protein aggregates containing TYLCV proteins and DNA. The maintenance of cellular chaperones in the aggregated state, even after recovery from heat stress, prevents the circulation of free soluble chaperones, causing an additional decrease in stress response efficiency. PMID:26792235

  7. AmeriFlux US-Tw3 Twitchell Alfalfa

    DOE Data Explorer

    Baldocchi, Dennis [University of California, Berkeley

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Tw3 Twitchell Alfalfa. Site Description - The Twitchell Alfalfa site is an alfalfa field owned by the state of California and leased to third parties for farming. The tower was installed on May 24, 2013. This site and the surrounding region are part of the San Joaquin - Sacramento River Delta drained beginning in the 1850's and subsequently used for agriculture. The field has been alfalfa for X years…., Crop rotation occurs every 5-6 years. The site is harvested by mowing and bailing several times per year. The field is fallow typically between November and February. The site is irrigated by periodically-flooded ditches surrounding the field. The site is irrigated by raising, and subsequently lowering the water table??

  8. Genetic Variation Within and Among Collections of Falata Alfalfas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Yellow-flowered alfalfa (Medicago sativa subsp. falcata) persists in low precipitation rangeland and grassland environments. The origin of Medicago includes Russia, Mongolia, Scandinavia, and China (Hansen, 1909; Lesins and Lesins, 1979). The presence of legumes improves rangelands and grasslands ...

  9. Cantharidin decreases in vitro digestion of alfalfa and smooth bromegrass.

    PubMed

    Lenssen, A W; Blodgett, S L; Higgins, R A; Nagaraja, T G; Posler, G L; Broce, A B

    1990-10-01

    Blister beetles (Coleoptera:Meloidae) containing the toxin cantharidin can be incorporated with alfalfa (Medicago sativa L) during forage conservation. Cantharidin inadvertently ingested with animal feed may cause illness or death. Little information is available on the effects of cantharidin on ruminant microbial digestion. The objective of our study was to determine cantharidin effects on digestibility of alfalfa and smooth bromegrass (Bromus inermis Leyss) by measuring in vitro digestible dry matter (IVDDM) and cell wall digestion (CWD). Alfalfa dry matter digestibility, measured after IVDDM at 48 and 96 h fermentation periods, decreased as cantharidin concentration increased. Increasing cantharidin concentration also significantly reduced IVDDM of smooth bromegrass at 24 and 96 h digestion time. The CWD of alfalfa and smooth bromegrass decreased as cantharidin concentration increased. These results indicate that ingestion of cantharidin by ruminants may decrease microbial digestion of fibrous feeds and therefore may decrease the efficiency of feed utilization by ruminants. PMID:2238434

  10. Soil characterization and differential patterns of heavy metal accumulation in woody plants grown in coal gangue wastelands in Shaanxi, China.

    PubMed

    Yakun, Shi; Xingmin, Mu; Kairong, Li; Hongbo, Shao

    2016-07-01

    Soil contamination by heavy metals in coal mine wastelands is a significant environmental issue in most developing countries. The purpose of this study is to evaluate contamination characteristics in the coal mine wastelands of Sanlidong coal mine, Tongchuan, China. To achieve this goal, we conducted field sampling work, followed by further analysis of the properties of soil contamination and accumulation characteristics in woody plants. At this site, the pH value ranged from 4.41 to 7.88, and the nutrient content of the soil rose gradually with the time after deposition due to the weathering effect improving the soil quality. Meanwhile, the levels of Cd, Cr, Cu, Ni, and Zn gradually decreased with the passage time. Generally, heavy metal contamination was found to be more serious in the discharge refuse area, with Cd contamination at moderate or heavy levels; Ni, Zn, and Cu contamination at light levels; and with no Cr contamination. The geoaccumulation index (I geo) was highest for Cd (2.38-3.14), followed by Ni, Zn, Cu, and Cr. Heavy metals accumulated on the lower slopes and spread to the surrounding areas via hydrodynamic effects and wind. According to transfer and enrichment coefficient analyses, Robinia pseudoacacia, Ulmus pumila, and Hippophae rhamnoides with considerable biomass could be used as pollution-resistant tree species for vegetation restoration. This study provided a theoretical basis for the restoration of the ecological environment in the mining area. This report described a link between heavy metal contamination of soils and growth dynamics of woody plants in China. PMID:27025220

  11. Plant available nitrogen from anaerobically digested sludge and septic tank sludge applied to crops grown in the tropics.

    PubMed

    Sripanomtanakorn, S; Polprasert, C

    2002-04-01

    Agricultural land is an attractive alternative for the disposal of biosolids since it utilises the recyclable nutrients in the production of crops. In Thailand and other tropical regions, limited field-study information exists on the effect of biosolids management strategies on crop N utilisation and plant available N (PAN) of biosolids. A field study was conducted to quantify the PAN of the applied biosolids, and to evaluate the N uptake rates of some tropical crops. Sunflower (Helianthus annuus) and tomato (Lycopersicon esculentum) were chosen in this study. Two types of biosolids used were: anaerobically digested sludge and septic tank sludge. The soil is acid sulfate and is classified as Sulfic Tropaquepts with heavy clay in texture. The anaerobically digested sludge applied rates were: 0, 156 and 312 kg N ha(-1) for the sunflower plots, and 0, 586, and 1172 kg N ha(-1) for the tomato plots. The septic tank sludge applied rates were: 0, 95 and 190 kg N ha(-1) for the sunflower plots, and 0, 354 and 708 kg N ha(-1) for the tomato plots, respectively. The results indicated the feasibility of applying biosolids to grow tropical crops. The applications of the anaerobically digested sludge and the septic tank sludge resulted in the yields of sunflower seeds and tomato fruits and the plant N uptakes comparable or better than that applied with only the chemical fertiliser. The estimated PAN of the anaerobically digested sludge was about 27-42% of the sludge organic N during the growing season. For the septic tank sludge, the PAN was about 15-58% of the sludge organic N. It is interesting to observe that an increase of the rate of septic tank sludge incorporated into this heavy clay soil under the cropping system resulted in the decrease of N mineralisation rate. This situation could cause the reduction of yield and N uptake of crops. PMID:12058820

  12. The gravitropic and phototropic responses of wheat grown in a space greenhouse prototype with hemispherical planting surface

    NASA Astrophysics Data System (ADS)

    Zyablova, N. V.; Berkovich, Yu. A.; Erokhin, A. N.; Skripnikov, A. Yu.

    2010-11-01

    The time course of gravicurvature of 3-day-old wheat ( Triticum aestivum L., cv. Apogee) coleoptiles and 7-day-old wheat stems were studied in darkness and under red and red-blue light illumination after declination from the vertical at various angles. The experiments showed that the shortest gravitropic curvature corresponded to 30° initial angle of gravistimulation (IAG). The time course became longer as the IAG increased and with plant age. The effects of unilateral red (660 nm) and red-blue light (660 nm; 470 nm) at photosynthetic photon flux (PPF) of 30 μmol m -2 s -1 on the curvature of 3-day-old coleoptiles were evaluated. Red light did not produce phototropic bending of wheat coleoptiles in contrast with red-blue light. The analysis of experimental data showed that the curvature in response to a gravitropic stimulus or to combined gravity-light stimuli were not statistically different. Time course of gravitropic curvature were used to determine the acceptable crop rotation rate around the horizontal axis. Approximation of stem bending to a linear dynamic system described by a first-order aperiodic element with a lag allowed the determination of the dependence of the amplitude of apex oscillations on the rate of horizontal rotation under 1-g conditions. The calculated lowest minimal rotation rate (MRR) minimizing the gravitropic effects on wheat was about 1 revolution per hour (rph). Rotating the plant growth chamber (PGC) at a rate of more than MRR eliminated the effect of gravitropic curvature.

  13. Changes in the chemical properties and swelling coefficient of alfalfa root cell walls in the presence of toluene as a toxic agent.

    PubMed

    Sharifi, M; Khoshgoftarmanesh, A H; Hadadzadeh, H

    2016-04-01

    The influence of toluene pollution on the chemical properties and swelling coefficient of root cell walls in alfalfa (Medicago sativa L.) was investigated. Two sets of alfalfa seedlings were selected and one set was treated with 450 mg L(-1) toluene in the nutrient solution under hydroponic culture. Thirty days after treatment with toluene, alfalfa plants were harvested and the root cell walls were isolated. Fourier-transform infrared (FTIR) spectroscopy was carried out for the characterization of the root cell walls composition. The cation exchange capacity (CEC) and the swelling coefficient of the root cell walls (Kcw) were estimated at various pH values. The toluene contamination significantly reduced the mass of the cell wall material in the alfalfa roots. According to the FTIR spectra, the toluene pollution can change the alfalfa root cell wall properties by reducing the cell wall functional groups. These functional groups are probably related to the proteins and polysaccharides in the cell wall. Also, toluene pollution strongly reduced CEC and Kcw of the root cell walls. The results show that the decrease in the active sites of adsorption on the root cell walls as a response to toluene pollution can affect the water flow rate and the mineral nutrients uptake by roots. PMID:26728292

  14. Transgenic expression of medicago truncatula PR10 and PR5 promoters in alfalfa shows pathogen-induced up-regulation of transgene expression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic modification of alfalfa to introduce novel traits requires promoters for controlling gene expression. Promoters that are constitutively activated for expression of genes that enhance disease resistance pose a great energy load on the plant and exert a strong selective pressure on the pathoge...

  15. Screening alfalfa, reed canarygrass, and switchgrass cultivars for ethanol yield by treating with dilute-acid followed by simultaneous saccharification and fermentation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa, reed canarygrass, and switchgrass are perennial herbaceous plants being considered for use as dedicated bioenergy crops because of their high productivity and favorable agronomics. However, selecting for cultivars with high conversion quality from among the diversity of genetic variants ava...

  16. Contribution of the pod wall to seed grain filling in alfalfa

    PubMed Central

    Wang, Hui; Hou, Longyu; Wang, Mingya; Mao, Peisheng

    2016-01-01

    Three genotypes of alfalfa viz. Medicago sativa (Zhongmu No. 1, Zhongmu No. 2) and M. varia (Caoyuan No. 3) grown in the filed were investigated for the contribution of pod wall and leaves by shading all pods and leaves on July 15, 20 and 25, respectively. Date was recorded for total pod weight (TPW), pod wall weight (PWW), seed weight per pod (SWP), seed number per pod (SNP) and single seed weight (SSW) of one-coil and two-coil spiral pods. TPW, SNP, PWW and SWP were reduced by shading all leaves or pods, whereas SSW was not significantly affected. The relative photosynthetic contribution of pod wall to SWP was 25.6–48.1% in three genotypes on July 15. The pod wall in one-coil spiral pods generated a greater relative contribution to the TPW and SWP than in two-coil spiral pods. In the last stage (July 25), the relative photosynthetic contribution of leaves to SWP sharply decreased, whereas the relative photosynthetic contribution of pod wall to SWP was stable in the late stage (July 20 and 25). In conclusion, the pod wall of alfalfa could carry out photosynthesis and the pod wall played an important role in pod filling at the late growth stage. PMID:27210048

  17. Contribution of the pod wall to seed grain filling in alfalfa.

    PubMed

    Wang, Hui; Hou, Longyu; Wang, Mingya; Mao, Peisheng

    2016-01-01

    Three genotypes of alfalfa viz. Medicago sativa (Zhongmu No. 1, Zhongmu No. 2) and M. varia (Caoyuan No. 3) grown in the filed were investigated for the contribution of pod wall and leaves by shading all pods and leaves on July 15, 20 and 25, respectively. Date was recorded for total pod weight (TPW), pod wall weight (PWW), seed weight per pod (SWP), seed number per pod (SNP) and single seed weight (SSW) of one-coil and two-coil spiral pods. TPW, SNP, PWW and SWP were reduced by shading all leaves or pods, whereas SSW was not significantly affected. The relative photosynthetic contribution of pod wall to SWP was 25.6-48.1% in three genotypes on July 15. The pod wall in one-coil spiral pods generated a greater relative contribution to the TPW and SWP than in two-coil spiral pods. In the last stage (July 25), the relative photosynthetic contribution of leaves to SWP sharply decreased, whereas the relative photosynthetic contribution of pod wall to SWP was stable in the late stage (July 20 and 25). In conclusion, the pod wall of alfalfa could carry out photosynthesis and the pod wall played an important role in pod filling at the late growth stage. PMID:27210048

  18. Transcriptional profile of Salmonella enterica subsp. enterica serovar Weltevreden during alfalfa sprout colonization

    PubMed Central

    Brankatschk, Kerstin; Kamber, Tim; Pothier, Joël F; Duffy, Brion; Smits, Theo H M

    2014-01-01

    Sprouted seeds represent a great risk for infection by human enteric pathogens because of favourable growth conditions for pathogens during their germination. The aim of this study was to identify mechanisms of interactions of Salmonella enterica subsp. enterica Weltevreden with alfalfa sprouts. RNA-seq analysis of S. Weltevreden grown with sprouts in comparison with M9-glucose medium showed that among a total of 4158 annotated coding sequences, 177 genes (4.3%) and 345 genes (8.3%) were transcribed at higher levels with sprouts and in minimal medium respectively. Genes that were higher transcribed with sprouts are coding for proteins involved in mechanisms known to be important for attachment, motility and biofilm formation. Besides gene expression required for phenotypic adaption, genes involved in sulphate acquisition were higher transcribed, suggesting that the surface on alfalfa sprouts may be poor in sulphate. Genes encoding structural and effector proteins of Salmonella pathogenicity island 2, involved in survival within macrophages during infection of animal tissue, were higher transcribed with sprouts possibly as a response to environmental conditions. This study provides insight on additional mechanisms that may be important for pathogen interactions with sprouts. PMID:24308841

  19. Citric acid- and Tween(®) 80-assisted phytoremediation of a co-contaminated soil: alfalfa (Medicago sativa L.) performance and remediation potential.

    PubMed

    Agnello, A C; Huguenot, D; van Hullebusch, E D; Esposito, G

    2016-05-01

    A pot experiment was designed to assess the phytoremediation potential of alfalfa (Medicago sativa L.) in a co-contaminated (i.e., heavy metals and petroleum hydrocarbons) soil and the influence of citric acid and Tween(®) 80 (polyethylene glycol sorbitan monooleate), applied individually and combined together, for their possible use in chemically assisted phytoremediation. The results showed that alfalfa plants could tolerate and grow in a co-contaminated soil. Over a 90-day experimental time, shoot and root biomass increased and negligible plant mortality occurred. Heavy metals were uptaken by alfalfa to a limited extent, mostly by plant roots, and their concentration in plant tissues were in the following order: Zn > Cu > Pb. Microbial population (alkane-degrading microorganisms) and activity (lipase enzyme) were enhanced in the presence of alfalfa with rhizosphere effects of 9.1 and 1.5, respectively, after 90 days. Soil amendments did not significantly enhance plant metal concentration or total uptake. In contrast, the combination of citric acid and Tween(®) 80 significantly improved alkane-degrading microorganisms (2.4-fold increase) and lipase activity (5.3-fold increase) in the rhizosphere of amended plants, after 30 days of experiment. This evidence supports a favorable response of alfalfa in terms of tolerance to a co-contaminated soil and improvement of rhizosphere microbial number and activity, additionally enhanced by the joint application of citric acid and Tween(®) 80, which could be promising for future phytoremediation applications. PMID:26838038

  20. New insights into pioneer root xylem development: evidence obtained from Populus trichocarpa plants grown under field conditions

    PubMed Central

    Bagniewska-Zadworna, Agnieszka; Arasimowicz-Jelonek, Magdalena; Smoliński, Dariusz J.; Stelmasik, Agnieszka

    2014-01-01

    Background and Aims Effective programmed xylogenesis is critical to the structural framework of the plant root system and its central role in the acquisition and long-distance transport of water and nutrients. The process of xylem differentiation in pioneer roots under field conditions is poorly understood. In this study it is hypothesized that xylogenesis, an example of developmental programmed cell death (PCD), in the roots of woody plants demonstrates a clearly defined sequence of events resulting in cell death. A comprehensive analysis was therefore undertaken to identify the stages of xylogenesis in pioneer roots from procambial cells to fully functional vessels with lignified cell walls and secondary cell wall thickenings. Methods Xylem differentiation was monitored in the pioneer roots of Populus trichocarpa at the cytological level using rhizotrons under field conditions. Detection and localization of the signalling molecule nitric oxide (NO) and hydrogen peroxide (H2O2) was undertaken and a detailed examination of nuclear changes during xylogenesis was conducted. In addition, analyses of the expression of genes involved in secondary cell wall synthesis were performed in situ. Key Results The primary event in initially differentiating tracheary elements (TEs) was a burst of NO in thin-walled cells, followed by H2O2 synthesis and the appearance of TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling)-positive nuclei. The first changes in nuclear structure were observed in the early stages of xylogenesis of pioneer roots, prior to lignification; however, the nucleus was detectable under transmission electron microscopy in differentiating cells until the stage at which vacuole integrity was maintained, indicating that their degradation was slow and prolonged. The subsequent sequence of events involved secondary cell wall formation and autophagy. Potential gene markers from the cinnamyl alcohol dehydrogenase (CAD) gene family that were

  1. Identification of transcriptome involved in atrazine detoxification and degradation in alfalfa (Medicago sativa) exposed to realistic environmental contamination.

    PubMed

    Zhang, Jing Jing; Lu, Yi Chen; Zhang, Shu Hao; Lu, Feng Fan; Yang, Hong

    2016-08-01

    Plants are constantly exposed to a variety of toxic compounds (or xenobiotics) such as pesticides (or herbicides). Atrazine (ATZ) as herbicide has become one of the environmental contaminants due to its intensive use during crop production. Plants have evolved strategies to cope with the adverse impact of ATZ. However, the mechanism for ATZ degradation and detoxification in plants is largely unknown. Here we employed a global RNA-sequencing (RNA-Seq) strategy to dissect transcriptome variation in alfalfa (Medicago sativa) exposed to ATZ. Four libraries were constructed including Root-ATZ (root control, ATZ-free), Shoot-ATZ, Root+ATZ (root treated with ATZ) and Shoot+ATZ. Hierarchical clustering was performed to display the expression patterns for all differentially expressed genes (DEGs) under ATZ exposure. Transcripts involved in ATZ detoxification, stress responses (e.g. oxidation and reduction, conjugation and hydrolytic reactions), and regulations of cysteine biosynthesis were identified. Several genes encoding glycosyltransferases, glutathione S-transferases or ABC transporters were up-regulated notably. Also, many other genes involved in oxidation-reduction, conjugation, and hydrolysis for herbicide degradation were differentially expressed. These results suggest that ATZ in alfalfa can be detoxified or degraded through different pathways. The expression patterns of some DEGs by high-throughput sequencing were well confirmed by qRT-PCR. Our results not only highlight the transcriptional complexity in alfalfa exposed to ATZ but represent a major improvement for analyzing transcriptional changes on a large scale as well. PMID:27092973

  2. Effect of application of ammonium chloride and calcium chloride on alfalfa cation-anion content and yield.

    PubMed

    Goff, J P; Brummer, E C; Henning, S J; Doorenbos, R K; Horst, R L

    2007-11-01

    A major factor predisposing the cow to periparturient hypocalcemia, or milk fever, is being fed a prepartum ration with a high dietary cation-anion difference (DCAD). The DCAD can be favorably altered to prevent milk fever by decreasing K and Na or increasing Cl and S in forages for cows in late gestation. The objective of this study was to test the hypothesis that application of Cl to alfalfa could increase Cl in forage, thereby lowering DCAD. We conducted a field experiment at 2 Iowa locations in which established plots of alfalfa were treated in April 2001 with 0, 56, 112, or 168 kg of Cl/ha using ammonium chloride, calcium chloride, or a mix of the 2 sources with equal amounts of chloride coming from each source. Plots were harvested 4 times in 2001 and once in 2002 and plant tissue analyzed for mineral composition. Applying chloride from either source once in the spring resulted in increased plant chloride content over all 4 cuttings for that year. Averaged across both locations, chloride levels were elevated from 0.52% in control plots to 0.77, 0.87, and 0.89% Cl in plots treated with 56, 112, and 168 kg of Cl/ha, respectively. Chloride application had no effect on plant potassium, sodium, calcium, magnesium, or phosphorus. These results suggest chloride application can elevate chloride content and lower DCAD values of alfalfa, and also maintain crop yield. PMID:17954756

  3. Comparative Physiological and Transcriptional Analyses of Two Contrasting Drought Tolerant Alfalfa Varieties

    PubMed Central

    Quan, Wenli; Liu, Xun; Wang, Haiqing; Chan, Zhulong

    2016-01-01

    Drought is one of major environmental determinants of plant growth and productivity. Alfalfa (Medicago sativa) is a legume perennial forage crop native to the arid and semi-arid environment, which is an ideal candidate to study the biochemical and molecular mechanisms conferring drought resistance in plants. In this study, drought stress responses of two alfalfa varieties, Longdong and Algonquin, were comparatively assayed at the physiological, morphological, and transcriptional levels. Under control condition, the drought-tolerant Longdong with smaller leaf size and lower stomata density showed less water loss than the drought-sensitive Algonquin. After exposing to drought stress, Longdong showed less severe cell membrane damage, more proline, and ascorbate (ASC) contents and less accumulation of H2O2 than Algonquin. Moreover, significantly higher antioxidant enzymes activities after drought treatment were found in Longdong when compared with Algonquin. In addition, transcriptional expression analysis showed that Longdong exhibited significantly higher transcripts of drought-responsive genes in leaf and root under drought stress condition. Taken together, these results indicated that Longdong variety was more drought-tolerant than Algonquin variety as evidenced by less leaf firing, more lateral root number, higher relative aboveground/underground biomass per plant and survival rate. PMID:26793226

  4. Inhibitory effect of essential oils obtained from plants grown in Colombia on yellow fever virus replication in vitro

    PubMed Central

    Meneses, Rocío; Ocazionez, Raquel E; Martínez, Jairo R; Stashenko, Elena E

    2009-01-01

    Background An antiviral drug is needed for the treatment of patients suffering from yellow fever. Several compounds present in plants can inactive in vitro a wide spectrum of animal viruses. Aim In the present study the inhibitory effect of essential oils of Lippia alba, Lippia origanoides, Oreganum vulgare and Artemisia vulgaris on yellow fever virus (YFV) replication was investigated. Methods The cytotoxicity (CC50) on Vero cells was evaluated by the MTT reduction method. The minimum concentration of the essential oil that inhibited virus titer by more than 50% (MIC) was determined by virus yield reduction assay. YFV was incubated 24 h at 4°C with essential oil before adsorption on Vero cell, and viral replication was carried out in the absence or presence of essential oil. Vero cells were exposed to essential oil 24 h at 37°C before the adsorption of untreated-virus. Results The CC50 values were less than 100 μg/mL and the MIC values were 3.7 and 11.1 μg/mL. The CC50/MIC ratio was of 22.9, 26.4, 26.5 and 8.8 for L. alba, L origanoides, O. vulgare and A. vulgaris, respectively. The presence of essential oil in the culture medium enhances the antiviral effect: L. origanoides oil at 11.1 μg/mLproduced a 100% reduction of virus yield, and the same result was observed with L. alba, O. vulgare and A. vulgaris oils at100 μg/mL. No reduction of virus yield was observed when Vero cells were treated with essential oil before the adsorption of untreated-virus. Conclusion The essential oils evaluated in the study showed antiviral activities against YFV. The mode of action seems to be direct virus inactivation. PMID:19267922

  5. Complete nucleotide sequence of Alfalfa mosaic virus isolated from alfalfa (Medicago sativa L.) in Argentina.

    PubMed

    Trucco, Verónica; de Breuil, Soledad; Bejerman, Nicolás; Lenardon, Sergio; Giolitti, Fabián

    2014-06-01

    The complete nucleotide sequence of an Alfalfa mosaic virus (AMV) isolate infecting alfalfa (Medicago sativa L.) in Argentina, AMV-Arg, was determined. The virus genome has the typical organization described for AMV, and comprises 3,643, 2,593, and 2,038 nucleotides for RNA1, 2 and 3, respectively. The whole genome sequence and each encoding region were compared with those of other four isolates that have been completely sequenced from China, Italy, Spain and USA. The nucleotide identity percentages ranged from 95.9 to 99.1 % for the three RNAs and from 93.7 to 99 % for the protein 1 (P1), protein 2 (P2), movement protein and coat protein (CP) encoding regions, whereas the amino acid identity percentages of these proteins ranged from 93.4 to 99.5 %, the lowest value corresponding to P2. CP sequences of AMV-Arg were compared with those of other 25 available isolates, and the phylogenetic analysis based on the CP gene was carried out. The highest percentage of nucleotide sequence identity of the CP gene was 98.3 % with a Chinese isolate and 98.6 % at the amino acid level with four isolates, two from Italy, one from Brazil and the remaining one from China. The phylogenetic analysis showed that AMV-Arg is closely related to subgroup I of AMV isolates. To our knowledge, this is the first report of a complete nucleotide sequence of AMV from South America and the first worldwide report of complete nucleotide sequence of AMV isolated from alfalfa as natural host. PMID:24510307

  6. Metabolomic profiling from leaves and roots of tomato (Solanum lycopersicum L.) plants grown under nitrogen, phosphorus or potassium-deficient condition.

    PubMed

    Sung, Jwakyung; Lee, Suyeon; Lee, Yejin; Ha, Sangkeun; Song, Beomheon; Kim, Taewan; Waters, Brian M; Krishnan, Hari B

    2015-12-01

    Specific metabolic network responses to mineral deficiencies are not well-defined. Here, we conducted a detailed broad-scale identification of metabolic responses of tomato leaves and roots to N, P or K deficiency. Tomato plants were grown hydroponically under optimal (5mM N, 0.5mM P, or 5mM K) and deficient (0.5mM N, 0.05mM P, or 0.5mM K) conditions and metabolites were measured by LC-MS and GC-MS. Based on these results, deficiency of any of these three minerals affected energy production and amino acid metabolism. N deficiency generally led to decreased amino acids and organic acids, and increased soluble sugars. P deficiency resulted in increased amino acids and organic acids in roots, and decreased soluble sugars. K deficiency caused accumulation of soluble sugars and amino acids in roots, and decreased organic acids and amino acids in leaves. Notable metabolic pathway alterations included; (1) increased levels of α-ketoglutarate and raffinose family oligosaccharides in N, P or K-deficient tomato roots, and (2) increased putrescine in K-deficient roots. These findings provide new knowledge of metabolic changes in response to mineral deficiencies. PMID:26706058

  7. Community Analysis of Root- and Tuber-Associated Bacteria in Field-Grown Potato Plants Harboring Different Resistance Levels against Common Scab

    PubMed Central

    Kobayashi, Akira; Kobayashi, Yuki Ohdaira; Someya, Nobutaka; Ikeda, Seishi

    2015-01-01

    Eight genotypes of potato plants with different resistance levels against common scab were grown in a field infested with Streptomyces turgidiscabies. DNA was extracted from the roots, tubers, and rhizosphere soils of each of the eight genotypes at the flowering stage, and the quantity of S. turgidiscabies genomic DNA was assessed by real-time PCR using a TaqMan probe. The results obtained showed that the different potato genotypes had significant impacts on the population levels of S. turgidiscabies between resistant and susceptible genotypes in the tubers, but not in the roots or rhizosphere soils. Clone analyses of 16S rRNA gene libraries from the eight potato genotypes identified three phyla (Proteobacteria, Firmicutes, and Actinobacteria) as dominant taxa in root and tuber clone libraries, while a clustering analysis identified 391 operational taxonomic units (OTUs) at the species level. Eleven OTUs closely related to Aquicella siphonis, Arthrobacter nicotinovorans, Streptomyces rishiriensis, Rhodococcus baikonurensis, Rhizobium radiobacter, Rhizobium etli, Phyllobacterium myrsinacearum, Paenibacillus pabuli, Paenibacillus alginolyticus, and Bacillus halmapalus were detected in the root or tuber libraries of all the potato genotypes examined. Furthermore, an abundance of OTUs related to Aquicella and Rhodococcus was observed in the rhizospheres of resistant and susceptible potato genotypes, respectively. Based on this ecological information, an efficient survey may be conducted for biological agents from the potato rhizosphere. PMID:26657303

  8. Conserving alfalfa wild relatives: is past introgression with Russian varieties evident today?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Central Asia, particularly Kazakhstan, supports a rich concentration of wild alfalfa (Medicago sativa L.) relatives. Because they freely cross with domesticated alfalfa, they are important genetic resources. When identifying in situ populations to conserve, contamination of wild populations with dom...

  9. [Evaluation of different levels of amaranth flour (vegetative parts), in substitution for alfalfa flour for growing rabbits].

    PubMed

    Alfaro, M A; Ramírez, R; Martínez, A; Bressani, R

    1987-03-01

    The vegetative part of the amaranth plant could be a useful resource for animal feeding due to its chemical characteristics and to the high yield obtained when harvested between 45 and 60 days after planting. Six diets were evaluated in order to determine the feed efficiency of amaranth (Amaranthus hypochondriacus) for growing rabbits. The diets contained dehydrated amaranth leaves and stalks in levels of 0, 15, 30, 45 and 60%, to replace equal amounts of alfalfa leaf meal. An additional diet containing 60% of steam-treated leaves and stalks of amaranth, for five minutes, prior to dehydration and milling, was also tested. The amaranth leaf meal contained 17.8% protein and 12.4% crude fiber as compared with the alfalfa leaf meal which contained 22.0% protein and 23.3% crude fiber. In terms of weight gain, feed intake, feed efficiency, carcass weight and serum proteins, the results indicated that amaranth leaf meal can efficiently replace alfalfa leaf meal up to 15% of the total weight of the diet. Higher levels, however, caused growth retardation and a pathological picture characterized by interstitial nephrosis and edema, more easily observed at a 60% level in the diet. Results also revealed that a steam treatment improves the nutritive quality of the amaranth meal. PMID:3454616

  10. Circulating fluidized bed combustion product addition to acid soil: alfalfa (Medicago sativa L.) composition and environmental quality.

    PubMed

    Chen, Liming; Dick, Warren A; Kost, David

    2006-06-28

    To reduce S emissions, petroleum coke with a high concentration of S was combusted with limestone in a circulating fluidized bed (CFB) boiler. The combustion process creates a bed product that has potential for agricultural uses. This CFB product is often alkaline and enriched in S and other essential plant nutrients, but also contains high concentrations of Ni and V. Agricultural land application of CFB product is encouraged, but little information is available related to plant responses and environmental impacts. CFB product and agricultural lime (ag-lime) were applied at rates of 0, 0.5, 1.0, and 2.0 times the soil's lime requirement (LR) to an acidic soil (Wooster silt loam). The 2.0x LR application rate of CFB product was equivalent to 67.2 Mg ha(-1). Alfalfa yield was increased 4.6 times by CFB product and 3.8 times by ag-lime compared to untreated control. Application of CFB product increased the concentration of V in soil and alfalfa tissue, but not in soil water, and increased the concentration of Ni in soil and soil water, but not in alfalfa tissue. However, these concentrations did not reach levels that might cause environmental problems. PMID:16787025

  11. Biodegradation of atrazine by three transgenic grasses and alfalfa expressing a modified bacterial atrazine chlorohydrolase gene.

    PubMed

    Vail, Andrew W; Wang, Ping; Uefuji, Hirotaka; Samac, Deborah A; Vance, Carroll P; Wackett, Lawrence P; Sadowsky, Michael J

    2015-06-01

    The widespread use of atrazine and other s-triazine herbicides to control weeds in agricultural production fields has impacted surface and groundwater in the United States and elsewhere. We previously reported the cloning, sequencing, and expression of six genes involved in the atrazine biodegradation pathway of Pseudomonas sp. strain ADP, which is initiated by atzA, encoding atrazine chlorohydrolase. Here we explored the use of enhanced expression of a modified bacterial atrazine chlorohydrolase, p-AtzA, in transgenic grasses (tall fescue, perennial ryegrass, and switchgrass) and the legume alfalfa for the biodegradation of atrazine. Enhanced expression of p-AtzA was obtained by using combinations of the badnavirus promoter, the maize alcohol dehydrogenase first intron, and the maize ubiquitin promoter. For alfalfa, we used the first intron of the 5'-untranslated region tobacco alcohol dehydrogenase gene and the cassava vein mosaic virus promoter. Resistance of plants to atrazine in agar-based and hydroponic growth assays was correlated with in vivo levels of gene expression and atrazine degradation. The in planta expression of p-atzA enabled transgenic tall fescue to transform atrazine into hydroxyatrazine and other metabolites. Results of our studies highlight the potential use of transgenic plants for bioremediating atrazine in the environment. PMID:25432082

  12. Alfalfa forage digestibility, quality and yield under future climate change scenarios vary with Sinorhizobium meliloti strain.

    PubMed

    Sanz-Sáez, Álvaro; Erice, Gorka; Aguirreolea, Jone; Muñoz, Fernando; Sánchez-Díaz, Manuel; Irigoyen, Juan José

    2012-05-15

    Elevated CO(2) may decrease alfalfa forage quality and in vitro digestibility through a drop in crude protein and an enhancement of fibre content. The aim of the present study was to analyse the effect of elevated CO(2), elevated temperature and Sinorhizobium meliloti strains (102F78, 102F34 and 1032 GMI) on alfalfa yield, forage quality and in vitro dry matter digestibility. This objective is in line with the selection of S. meliloti strains in order to maintain high forage yield and quality under future climate conditions. Plants inoculated with the 102F34 strain showed more DM production than those inoculated with 1032GMI; however, these strains did not show significant differences with 102F78 plants. Neutral or acid detergent fibres were not enhanced in plants inoculated with the 102F34 strain under elevated CO(2) or temperature and hence, in vitro dry matter digestibility was unaffected. Crude protein content, an indicator of forage quality, was negatively related to shoot yield. Plants inoculated with 102F78 showed a similar shoot yield to those inoculated with 102F34, but had higher crude protein content at elevated CO(2) and temperature. Under these climate change conditions, 102F78 inoculated plants produced higher quality forage. However, the higher digestibility of plants inoculated with the 102F34 strain under any CO(2) or temperature conditions makes them more suitable for growing under climate change conditions. In general, elevated CO(2) in combination with high temperature (Climate Change scenario) reduced IVDMD and CP content and enhanced fibre content, which means that animal production will be negatively affected. PMID:22369772

  13. Bacterial population dynamics during the ensiling of Medicago sativa (alfalfa) and subsequent exposure to air

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aims: To describe, at high resolution, the bacterial population dynamics and chemical transformations during the ensiling of alfalfa and subsequent exposure to air. Methods and Results: Samples of alfalfa, ensiled alfalfa, and silage exposed to air were collected and their bacterial population stru...

  14. Comparison of Alfalfa and Orchardgrass Hay as Replacements for Grain in Lactating Dairy Cow Diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While alfalfa has been the predominant perennial forage fed to dairy cows in the Midwest, there has been recent interest to increase use of perennial grasses. This interest is because alfalfa can be expensive to produce (short stand life), the perception that manure cannot be applied to alfalfa, and...

  15. Stand age affects fertilizer nitrogen response in first-year corn following alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The amount of N that alfalfa (Medicago sativa L.) provides to subsequent first-year corn (Zea mays L.) depends, in part, on the age of alfalfa at termination. Our objective was to determine how alfalfa stand age affects N availability and fertilizer N requirements for first-year corn. Fertilizer N w...

  16. Combining cropland data layers to identify alfalfa-annual crop rotation patterns and opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L.) can provide many economic and environmental benefits to crop rotations. Our objectives were to quantify alfalfa stand lengths, identify the two crops following alfalfa, and determine the soil and temporal factors affecting them. The USDA-NASS cropland data layers for 200...

  17. Pollen and seed mediated gene flow in commercial alfalfa seed production fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential for gene flow has been widely recognized since alfalfa is pollinated by bees. The Western US is a major exporter of alfalfa seed and hay and the organic dairy industry is one of the fastest growing agricultural sectors. Because of this, many alfalfa producers are impacted by market sen...

  18. Transgene movement in commercial alfalfa seed production: Implications for seed purity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The United States is a major exporter of alfalfa seed and hay and the organic dairy industry is one of the fastest growing agricultural sectors. With the advent of genetically-engineered (GE) alfalfa concerns have risen regarding the coexistence of GE and non GE alfalfa since the crop is largely ou...

  19. Pythium species causing damping-off of alfalfa in Minnesota: Identification, pathogenicity and fungicide sensitivity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Damping-off and seed rot is an important disease of alfalfa, severely affecting stand establishment when conditions favor the disease. Globally, 15 Pythium species are reported to cause damping-off and seed rot of alfalfa, although surveys of species causing disease on alfalfa in Minnesota are lacki...

  20. Genomic Analysis of Verticillium Wilt Resistance and Drought Tolerance in Alfalfa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alfalfa (Medicago sativa L.) is the fourth largest crop in the United States. Changing trends to multipurpose uses increases demand for alfalfa. However, the production of alfalfa is challenged by endemic and emerging diseases and adverse environmental factors. Identification of genes/loci controlli...