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Sample records for plants zea mais

  1. Isolation of 14{sub C} labelled amino acids by biosynthesis in maize plants (Zea mais L.); Obtencin de aminoacidos marcados con 14{sub C} por biosintesis en plantulas de maiz (Zea mais L)

    Energy Technology Data Exchange (ETDEWEB)

    Carreras, N.; Mazon, M. P.

    1983-07-01

    A method of obtaining 14{sub C} labelled amino acids by biosynthesis in maize plants which had assimilated 14CO{sub 2}, has been assayed. The plants were labelled for 60 minutes with 14{sub C}O2 produced from Ba 14{sub C}O3 (specific activity of 148 KBq/{mu}mol). An extract of the soluble compounds was obtained with 80% ethanol and the amino acids were separated from the rest of the soluble compounds by ion exchange chromatography on column of Dowex 50-X8 resin. Finally, seventeen amino acids were isolated and identified from the purified extract. The acid amino acids were separated in anionic column (Dowex 1-X8) and the neutral and basic amino acids in cationic column (Dowex 50-X4). (Author) 56 refs.

  2. Influence de l'age sur les caracteristiques photosynthetiques de la feuille de mais , Zea mays L.

    OpenAIRE

    Bethenod, Olivier; Jacob, Christine; Rode, J. C.; Morot-Gaudry, Jean-Francois

    1982-01-01

    L’assimilation nette maximale (N max) du maïs, Zea mays L., rapportée à l’unité de surface foliaire et de temps, reste stationnaire de juillet à août puis décroît de septembre à octobre durant le remplissage du grain. L’examen des courbes d’assimilation nette en fonction de la concentration en C02, sous éclairement saturant, montre que jusqu’au stade grain laiteux-pâteux, la photosynthèse maximale du maïs dépend du niveau du plateau de double saturation en C02 et en lumière (Pm). Du s...

  3. The effect of lead on the photoelectric reaction of Zea mays L. plants.

    Science.gov (United States)

    Pazurkiewicz-Kocot, K; Pietruszka, M

    2000-09-01

    We investigate the correlation between the concentrations of lead (10(-6)-10(-2) mol dm(-3) PbCl2) in the external medium and photoelectric reaction of Zea mays L. plants. The experiments were carried out on 8-10-day-old maize plants (Zea mays L. var. K33 x F2) with the use of conventional electrophysiological technique. The results suggest that in plants treated with lead ions the photoelectric reaction is significantly reduced. The pH variation of the incubation medium including the green fragments of leaves showed that lead ions caused inhibition of light-induced external acidification.

  4. Selection and adaptation to high plant density in the Iowa Stiff Stalk synthetic maize (Zea mays L.) population

    Science.gov (United States)

    The plant density at which Zea mays L. hybrids achieve maximum grain yield has increased throughout the hybrid era while grain yield on a per plant basis has increased little. Changes in plant traits including grain yield, moisture, test weight, and stalk and root lodging have been well characterize...

  5. Zea mays

    African Journals Online (AJOL)

    Dr kelechi

    It involved the extraction of the chlorophyll of 1 g of each leaf with 10 ml of 80% acetone. .... photosynthesis level in the plant with resultant poor performance of ... on germination, early seedling growth and pigment content in maize. (Zea mays ...

  6. Selection and adaptation to high plant density in the Iowa Stiff Stalk synthetic maize (Zea mays L.) population: II. Plant morphology

    Science.gov (United States)

    The plant density at which Zea mays L. hybrids achieve maximum grain yield has increased throughout the hybrid era while grain yield on a per plant basis has increased little. Changes in plant characteristics including flag leaf angle, anthesis-silking interval (ASI), plant height, tassel branch num...

  7. TOXICITY OF METHYL-TERT BYTYL ETHER (MTBE) TO PLANTS (AVENA SATIVA, ZEA MAYS, TRITICUM AESTIVUM, AND LACTUCA SATIVA)

    Science.gov (United States)

    Effects of Methyl tert-butyl ether (MTBE) on the germination of seeds and growth of the plant were studied in some laboratory experiments. Test plants were wild oat (Avena sative), sweet corn (Zea mays), wheat (Triticum aestivum), and lettuce (Lactuca sativa). Seed germination,...

  8. TOXICITY OF METHYL-TERT BYTYL ETHER (MTBE) TO PLANTS (AVENA SATIVA, ZEA MAYS, TRITICUM AESTIVUM, AND LACTUCA SATIVA)

    Science.gov (United States)

    Effects of Methyl tert-butyl ether (MTBE) on the germination of seeds and growth of the plant were studied in some laboratory experiments. Test plants were wild oat (Avena sative), sweet corn (Zea mays), wheat (Triticum aestivum), and lettuce (Lactuca sativa). Seed germination,...

  9. Effect of simultaneous establishment of Sedum alfredii and Zea mays on heavy metal accumulation in plants.

    Science.gov (United States)

    Liu, Xiaomei; Wu, Qitang; Banks, M Katherine

    2005-01-01

    Land application of biosolids to improve agricultural productivity is a cost-effective approach for resource recovery. Unfortunately, municipal biosolids often contain high concentrations of heavy metals, including zinc and copper. In this study, a co-cropping technique was investigated using a known zinc hyperaccumulator, Sedum alfredii with a grain crop, Zea mays. After a 3-mo growth trial, the results indicate that when Z. mays is co-cropped with S. alfredii, heavy metals accumulated in the grains were significantly reduced when compared to monoculture cropping. Co-cropping improved the growth of both plant species. In addition, the biosolids maintained stable pH, N-P-K concentrations, germination potential, and water content after the plant treatment, regardless of the plant species used in the trial. In conclusion, co-cropping with hyperaccumulators may be an effective approach to reducing the risk of contaminant uptake in edible crops.

  10. Endophytic Phoma sp. isolated from medicinal plants promote the growth of Zea mays

    Directory of Open Access Journals (Sweden)

    ASHWINI KEDAR

    2014-11-01

    Full Text Available Kedar A, Rathod D, Yadav A, Agarkar G, Rai M. 2014. Endophytic Phoma sp. isolated from medicinal plants promote the growth of Zea mays. Nusantara Bioscience 6: 132-139. Fungal endophytes are reported as rich sources of valuable secondary metabolites and could be used as bio-fertilizers. In the present study, we report growth promotion potential of two Phoma species isolated from Tinospora cordifolia and Calotropis procera on maize. The fungal endophytes enhanced growth in inoculated maize plants compared to non-inoculated plants. The main aim of this work was to assess the growth promotion activity of endophytic Phoma species on maize isolated from T. cordifolia and C. procera.

  11. Proteus mirabilis alleviates zinc toxicity by preventing oxidative stress in maize (Zea mays) plants.

    Science.gov (United States)

    Islam, Faisal; Yasmeen, Tahira; Riaz, Muhammad; Arif, Muhammad Saleem; Ali, Shafaqat; Raza, Syed Hammad

    2014-12-01

    Plant-associated bacteria can have beneficial effects on the growth and health of their host. However, the role of plant growth promoting bacteria (PGPR), under metal stress, has not been widely investigated. The present study investigated the possible mandatory role of plant growth promoting rhizobacteria in protecting plants from zinc (Zn) toxicity. The exposure of maize plants to 50µM zinc inhibited biomass production, decreased chlorophyll, total soluble protein and strongly increased accumulation of Zn in both root and shoot. Similarly, Zn enhanced hydrogen peroxide, electrolyte leakage and lipid peroxidation as indicated by malondaldehyde accumulation. Pre-soaking with novel Zn tolerant bacterial strain Proteus mirabilis (ZK1) isolated zinc (Zn) contaminated soil, alleviated the negative effect of Zn on growth and led to a decrease in oxidative injuries caused by Zn. Furthermore, strain ZK1 significantly enhanced the activities of catalase, guaiacol peroxidase, superoxide dismutase and ascorbic acid but lowered the Proline accumulation in Zn stressed plants. The results suggested that the inoculation of Zea mays plants with P. mirabilis during an earlier growth period could be related to its plant growth promoting activities and avoidance of cumulative damage upon exposure to Zn, thus reducing the negative consequences of oxidative stress caused by heavy metal toxicity. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Impact of rhizobial inoculation and nitrogen utilization in plant growth promotion of maize (Zea mays L.

    Directory of Open Access Journals (Sweden)

    RAMESH K. SINGH

    2013-05-01

    Full Text Available Singh RK, Malik N, Singh S. 2013. Impact of rhizobial inoculation and nitrogen utilization in plant growth promotion of maize (Zea mays L.. Nusantara Bioscience 5: 8-14. During the course of growing population demands there has been an increasing interest in exploring the possibility of extending the beneficial interaction between cereals and plant growth promoting rhizobacteria (PGPR. Endophytes are a group of microorganism that resides mostly in the intercellular space of various parts of plants including cereals. Assessment of plant growth promoting properties of the five-rhizobial strains belonging to α subclass i.e. Rhizobium leguminosarum bv. phaseoli RRE6 and R. undicola RRE36 and those belonging to β subclass i.e. Burkholderia cepacia (RRE3, RRE5, RRE25 was done by growing maize plants inoculated with these strains. Inoculated maize plants showed a significant increase in plant height, root length, shoot and root dry weight over uninoculated control. R. leguminosarum bv. phaseoli RRE6 and B. cepacia RRE5 among the α and β-subclass representatives respectively, gave the best inoculation response. Effect of nitrate supplementation upon maize-RRE6 and RRE5 association was also studied and a significant increase in all the growth parameters and colonization ability was recorded when nitrate was present as a supplement over uninoculated control and maize-RRE6 and RRE5 in absence of external nitrate.

  13. Effect of selenite and selenate on plant uptake of cadmium by maize (zea mays)

    Energy Technology Data Exchange (ETDEWEB)

    Shanker, K.; Mishra, S.; Srivastava, S. [Dayalbagh Educational Institute (India)

    1996-03-01

    Selenium has been reported to confer tolerance to toxicity of heavy metals including cadmium, a highly toxic and non essential heavy metal, which enters the food chain via plant uptake from soils. Selenium reduces availability of cadmium to plants along with other aspects of its toxicokinetics. When plants are supplied with selenite, selenium concentrations in the xylem exudate are lower than selenate. Most of the selenate was transported as selenate and unidentified organic Se compounds. In contrast, Se distribution among various Se fractions within plants does not depend significantly on whether selenite or selenate was used. Selenium has a strong tendency to form complexes with heavy metals like Cd, Hg, Ag and Tl. It has been suggested that the protective effects of selenium are due to the formation of non toxic Se-metal complexes, although the mechanism by which this protective effect is exerted remains unclear. Studies on the effect of selenium (selenite) and cadmium additions to the soil on their concentrations in lettuce and wheat has indicated the role of selenite in reduction of cadmium uptake. The cletoxifying effect of sodium selenite on cadmium ion in the freshwater fish Potyacuthus cupanus has been reported. The discovery that an element like selenium counteracts the toxicity, chemical carcinogenesis and reduces the plant uptake of other toxic metals, highlights the possibility of existence of a Se-metal interaction mechanism in soil plant systems. The uptake and translocation of root-absorbed chromium supplied through irrigation in the trivalent and hexavalant states in various parts of the onion plant (Allium cepa) grown in soil and sand culture has been recently reported by us. In continuation of that, this preliminary report describes the effect of selenite and selenate pretreatment on the uptake of cadmium in the maize plant (Zea mays).

  14. Growth responses of plants to various concentrations of nitrogen dioxide. [Helianthus annuus L. ; Zea mays L

    Energy Technology Data Exchange (ETDEWEB)

    Okano, K.; Totsuka, T.; Fukuzawa, T.; Tazaki, T.

    1985-01-01

    Sunflower Helianthus annuus L. and maize Zea mays L. plants in the vegetative phase were exposed to nitrogen dioxide (NO2) at 0.0 (control), 0.2, 0.5 and 1.0 ppm ( l liter ) for 2 weeks. The growth responses of the plants to NO2 were examined by the techniques of growth analysis. The sunflower plant was more susceptible to NO2 than the maize plant. Exposure to NO2 at 0.2 ppm slightly stimulated the growth of the sunflower plants. The net assimilation rate (NAR) was also significantly increased when the plants were exposed to 0.2 ppm NO2. Exposures to NO2 at 0.5 or more significantly reduced the dry weight of the sunflower plant. Of the component parts, the roots and stems were severely affected, while the leaves were less affected. This resulted in an elevated shoot/root ratio. The net assimilation rate of both species was reduced by the exposures to NO2 at 0.5 ppm or more, while, in contrast, the leaf area ratio (LAR) was increased. The relative growth rate (RGR), the product of the NAR and the LAR, was therefore less affected by NO2. The increase in the LAR was overwhelmingly the result of an increase in the leaf weight ratio (LWR). These results imply that a reduction in photosynthetic efficiency induced by NO2 could be, in part, compensated for by an increase in assimilatory area, suggesting an adaptive growth response of the plants to air pollutant stresses.

  15. Plant species coexistence alleviates the impacts of lead on Zea mays L.

    Institute of Scientific and Technical Information of China (English)

    Ruyi Yang; Ling Liu; Shuting Zan; Jianjun Tang; Xin Chen

    2012-01-01

    Whether plant coexistence can reduce the impacts of lead(Pb)on crops in agroecosystems has not been well understood.We conducted a factorial experiment to investigate the effects of weeds coexisting with maize(Zea mays L.)on Pb accumulation in maize and soil microbes at two Pb levels(ambient and 300 mg/kg).Elevated Pb tended to increase the Pb concentration in maize and decreased soil microbial activity(indicated by the average well color development,AWCD),functional group diversity,as well as arbuscular mycorrhizal(AM)colonization and vesicle number of maize.Compared to the monoculture,weeds coexisting with maize reduced the Pb concentrations in the root,leaf,sheath and stem of maize at both seedling and mature stages.In maize-weed mixtures,soil microbial activity and functional group diversity tended to increase for both Pb treatments relative to the monoculture.Furthermore,principal component analysis revealed that the soil microbial community structure changed with the introduction of weeds.The highest Pb accumulation in weeds occurred for the elevated Pb treatment in a three species mixture.The results suggest that multiple plant species coexistence could reduce lead accumulation in crop plants and alleviate the negative impacts on soil microbes in polluted land,thereby highlighting the significance of plant diversity in agroecosystems.

  16. Nematode suppression and growth stimulation in corn plants (Zea mays L.) irrigated with domestic effluent.

    Science.gov (United States)

    Barros, Kenia Kelly; do Nascimento, Clístenes Williams Araújo; Florencio, Lourdinha

    2012-01-01

    Treated wastewater has great potential for agricultural use due to its concentrations of nutrients and organic matter, which are capable of improving soil characteristics. Additionally, effluents can induce suppression of plant diseases caused by soil pathogens. This study evaluates the effect of irrigation with effluent in a UASB reactor on maize (Zea mays L.) development and on suppression of the diseases caused by nematodes of the genus Meloidogyne. Twelve lysimeters of 1 m(3) each were arranged in a completely randomized design, with four treatments and three replicates. The following treatments were used: T1 (W+I), irrigation with water and infestation with nematodes; T2 (W+I+NPK), irrigation with water, infestation with nematodes and fertilization with nitrogen (N), phosphorus (P) and potassium (K); T3 (E+I), irrigation with effluent and infestation with nematodes; and T4 (E+I+P), irrigation with effluent, infestation with nematodes and fertilization with phosphorus. The plants irrigated with the effluent plus the phosphorus fertilizer had better growth and productivity and were more resistant to the disease symptoms caused by the nematodes. The suppression levels may have been due to the higher levels of Zn and NO(3)(-) found in the leaf tissue of the plants irrigated with the effluent and phosphorus fertilizer.

  17. The effect of bottom sediment supplement on heavy metals content in plants (Zea mays and soil

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    Baran A.

    2013-04-01

    Full Text Available Important aspect of bottom sediments is the problem of their management or disposal after their extraction from the bottom of rivers, dam reservoirs, ports, channels or ponds. The research aimed at an assessment of potential environmental management of bottom sediment used as an admixture to light soil basing on its effect on contents of heavy metals in plants and soil. The research was conducted on light soil with granulometric structure of weakly loamy sand. The bottom sediment was added to light soil in the amount of 0 (control 5, 10, 30 i 50%. The test plant was maize (Zea mays, “Bora” c.v. The sediment applied in the presented research revealed high share of silt and clay fractions, alkaline pH and low contents of heavy metals, therefore it may be used as an admixture to the above mentioned soils to improve their productivity. The applied bottom sediment to the soil affected a decreased in Zn, Cd and Pb content in maize in comparison with the treatment without the deposit whereas increased content of Cu, Cr and Ni. No exceeded permissible content of heavy metals concerning plant assessment in view of their forage usability were registered in maize biomass.

  18. Woody plant diversity in sacred forests and fallows in Chiang Mai, Thailand

    DEFF Research Database (Denmark)

    Junsongduang, A.; Balslev, Henrik; Jampeetong, Arunothai;

    2014-01-01

    ; old fallow, 5-6 years old). All woody plant species were identified and counted in three transects (20 x 40 m) . Seedlings were inventoried in 12 circular (5 m diam.) plots. The highest species richness of all woody species and seedlings were found in the sacred forests in both villages. The highest......All woody plant and seedling diversity was compared in a Karen and a Lawa hill-tribe village in northern Thailand in four different habitats: sacred forests and fallow fields of three ages derived from rotational shifting cultivation (young fallows, 1–2 years old; medium-age fallow, 3-4 years old...... values of the Shannon-Wiener index for both trees and seedlings were in the sacred forest of the Karen village. There were significant differences in species richness between the four studied habitats surrounding both villages (pplant and seedlings species compositions in the sacred...

  19. Survivorship of Helicoverpa zea and Heliothis virescens on cotton plant structures expressing a Bacillus thuringiensis vegetative insecticidal protein.

    Science.gov (United States)

    Bommireddy, P L; Leonard, B R

    2008-08-01

    A series of tests quantified bollworm, Helicoverpa zea (Boddie), and tobacco budworm, Heliothis virescens (F.), larval survival on plant structures of a nontransgenic cotton (Gossypium hirsutum L.), 'Coker 312', and two transgenic cottons expressing Vip3A protein or both Vip3A + CrylAb proteins (VipCot). Vegetative and reproductive structures including terminal leaves, flower bud (square) bracts, whole debracted squares, flower petals, flower anthers, and intact capsules (bolls) were harvested from plants in field plots. Each structure was infested with 2-d-old larvae from one of the two heliothine species. Larvae were allowed to feed for 96 h on fresh tissue. Survivorship at 96 h after infestation was significantly lower on all structures of Vip3A and VipCot cotton lines compared with similar structures of Coker 312. VipCot plant structures generally resulted in lower larval survivorship compared with similar structures of the Vip3A cotton line. H. zea survivorship ranged from 4 to 28% and from 1 to 18% on Vip3A and VipCot plant structures, respectively. H. virescens survivorship ranged from 10 to 43% and from 2 to 12% on Vip3A and VipCot plant structures, respectively. H. virescens survivorship was higher on VIP3A plant structures compared with that for H. zea on similar structures. These differences between species were not observed on plants from the cotton line expressing VipCot proteins. The results for these plant structures demonstrate that the combination of proteins expressed in VipCot cotton lines are more effective than Vip3A cotton lines against this heliothine complex.

  20. Evaluating the physiological state of maize (Zea mays L.) plants by direct-injection electrospray mass spectrometry (DIESI-MS).

    Science.gov (United States)

    García-Flores, Martín; Juárez-Colunga, Sheila; Montero-Vargas, Josaphat Miguel; López-Arciniega, Janet Ana Isabel; Chagolla, Alicia; Tiessen, Axel; Winkler, Robert

    2012-06-01

    Climatic change is an increasing challenge for agriculture that is driving the development of suitable crops in order to ensure supply for both human nutrition and animal feed. In this context, it is increasingly important to understand the biochemical responses of cells to environmental cues at the whole system level, an aim that is being brought closer by advances in high throughput, cost-efficient plant metabolomics. To support molecular breeding activities, we have assessed the economic, technical and statistical feasibility of using direct mass spectrometry methods to evaluate the physiological state of maize (Zea mays L.) plants grown under different stress conditions.

  1. Significance of diazotrophic plant growth-promoting Herbaspirillum sp. GW103 on phytoextraction of Pband Zn by Zea mays L.

    Science.gov (United States)

    Praburaman, Loganathan; Park, Sung-Hee; Cho, Min; Lee, Kui-Jae; Ko, Jeong-Ae; Han, Sang-Sub; Lee, Sang-Hyun; Kamala-Kannan, Seralathan; Oh, Byung-Taek

    2017-01-01

    Microbe-assisted phytoremediation has been considered a promising measure for the remediation of heavy metal-polluted soil. The aim of this study was to assess the effect of diazotrophic plant growth-promoting Herbaspirillum sp. GW103 on growth and lead (Pb) and zinc (Zn) accumulation in Zea mays L. The strain GW103 exhibited plant growth-promoting traits such as indole-3-acetic acid, siderophores, and 1-aminocyclopropane-1-carboxylic deaminase. Treatment of Z. mays L. plants with GW103 significantly increased 19, 31, and 52% of plant biomass and 10, 50, and 126% of chlorophyll a contents in Pb, Zn, and Pb + Zn-amended soils, respectively. Similarly, the strain GW103 significantly increased Pb and Zn accumulation in shoots and roots of Z. mays L., which were 77 and 25% in Pb-amended soil, 42 and 73% in Zn-amended soil, and 27 and 84% in Pb + Zn-amended soil. Furthermore, addition of GW103 increased 8, 12, and 7% of total protein content, catalase, and superoxide dismutase levels, respectively, in Z. mays L. plants. The results pointed out that isolate GW103 could potentially reduce the phytotoxicity of metals and increase Pb and Zn accumulation in Z. mays L. plant.

  2. Weed Control and Corn (Zea mays Response to Planting Pattern and Herbicide Program with High Seeding Rates in North Carolina

    Directory of Open Access Journals (Sweden)

    Mitchell K. Williams

    2014-01-01

    Full Text Available Effective weed control in corn (Zea mays L. is important to optimize yield. Concern over environmental impact of atrazine and selection for glyphosate resistance has increased the need to develop alternative strategies that use herbicides other than atrazine and glyphosate and appropriate cultural practices to control weeds. Research was conducted during 2011 and 2012 to determine weed and corn response to herbicide programs containing dicamba, glufosinate, and glyphosate applied postemergence alone or with atrazine in single- and twin-row planting patterns. Planting pattern had no effect on common ragweed (Ambrosia artemisiifolia L. and Texas panicum (Panicum texanum L. population and did not interact with herbicide program. Effective weed control hastened maturity in some but not all instances. Under weed-free conditions, corn grain yield was higher in 5 of 7 trials when planted in twin rows versus single rows at equivalent corn populations (141,000 plants ha−1. These results suggest that while planting pattern may not impact weed control dramatically, planting corn in twin rows may be an effective alternative to single-row planting patterns because of increased yield under high corn populations.

  3. Interactions between Fusarium verticillioides, Ustilago maydis, and Zea mays: an endophyte, a pathogen, and their shared plant host.

    Science.gov (United States)

    Rodriguez Estrada, Alma E; Jonkers, Wilfried; Kistler, H Corby; May, Georgiana

    2012-07-01

    Highly diverse communities of microbial symbionts occupy eukaryotic organisms, including plants. While many well-studied symbionts may be characterized as either parasites or as mutualists, the prevalent but cryptic endophytic fungi are less easily qualified because they do not cause observable symptoms of their presence within their host. Here, we investigate the interactions of an endophytic fungus, Fusarium verticillioides with a pathogen, Ustilago maydis, as they occur within maize (Zea mays). We used experimental inoculations to evaluate metabolic mechanisms by which these three organisms might interact. We assessed the impacts of fungal-fungal interactions on endophyte and pathogen growth within the plant, and on plant growth. We find that F. verticillioides modulates the growth of U. maydis and thus decreases the pathogen's aggressiveness toward the plant. With co-inoculation of the endophyte with the pathogen, plant growth is similar to that which would be gained without the pathogen present. However, the endophyte may also break down plant compounds that limit U. maydis growth, and obtains a growth benefit from the presence of the pathogen. Thus, an endophyte such as F. verticillioides may function as both a defensive mutualist and a parasite, and express nutritional modes that depend on ecological context. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Differences on Pb accumulation among plant tissues of 25 varieties of maize (Zea mays)

    Institute of Scientific and Technical Information of China (English)

    DAI Quanlin; YUAN Jiangang; FANG Wei; YANG Zhongyi

    2007-01-01

    Pollution of agricultural land by heavy metals has imposed an increasingly serious risk to environmental and human health in recent years.Heavy metal pollutants may enter the human food chain through agricultural products and groundwater from the polluted soils.Progress has been made in the past decade on phytoremediation,a safe and inexpensive approach to remove contaminants from soil and water using plants.However,in most cases,agricultural land in China cannot afford to grow phytoremediator plants instead of growing crops due to food supply for the great population.Therefore,new and effective methods to decrease the risk of heavy metal pollution in crops and to clean the contaminated soils are urgently needed.If we can find crop germplasms (including species and varieties) that accumulate heavy metals in their edible parts,such as the leaves of vegetables or grains of cereals,at a level low enough for safe consumption,then we can grow these selected species or varieties in the lands contaminated or potentially contaminated by heavy metals.If we can find crop germplasms that take in low concentrations of heavy metals in their edible parts and high content of the metals in their inedible parts,then we can use these selected species or varieties for soil remediation.In this study,the feasibility of the method is assessed by analyzing Pb concentrations in edible and inedible parts of 25 varieties of maize (Zea mays) grown in Pb-contaminated soils.The soil concentrations of Pb were 595.55 mg/kg in the high Pb exposed treatment and 195.55 mg/kg in the control.The results showed that the Pb concentrations in different tissues were in the order of root > shoot ≌ leaf> grain.Compared with the control,the Pb concentrations in root,shoot and leaf were greatly increased under the high Pb exposed condition,while the increments of Pb concentration in grain were relatively lower.Under the high Pb exposure,the grain Pb concentrations of 12 varieties exceeded the maximal

  5. Maize (Zea mays)-derived bovine trypsin: characterization of the first large-scale, commercial protein product from transgenic plants.

    Science.gov (United States)

    Woodard, Susan L; Mayor, Jocelyne M; Bailey, Michele R; Barker, Donna K; Love, Robert T; Lane, Jeffrey R; Delaney, Donna E; McComas-Wagner, Janet M; Mallubhotla, Hanuman D; Hood, Elizabeth E; Dangott, Lawrence J; Tichy, Shane E; Howard, John A

    2003-10-01

    Bovine trypsin (EC 3.4.21.4) is an enzyme that is widely used for commercial purposes to digest or process other proteins, including some therapeutic proteins. The biopharmaceutical industry is trying to eliminate animal-derived proteins from manufacturing processes due to the possible contamination of these products by human pathogens. Recombinant trypsin has been produced in a number of systems, including cell culture, bacteria and yeast. To date, these expression systems have not produced trypsin on a scale sufficient to fulfill the need of biopharmaceutical manufacturers where kilogram quantities are often required. The present paper describes commercial-level production of trypsin in transgenic maize (Zea mays) and its physical and functional characterization. This protease, the first enzyme to be produced on a large-scale using transgenic plant technology, is functionally equivalent to native bovine pancreatic trypsin. The availability of this reagent should allow for the replacement of animal-derived trypsin in the processing of pharmaceutical proteins.

  6. Phytomanagement of Cd-contaminated soils using maize (Zea mays L.) assisted by plant growth-promoting rhizobacteria.

    Science.gov (United States)

    Moreira, Helena; Marques, Ana P G C; Franco, Albina R; Rangel, António O S S; Castro, Paula M L

    2014-01-01

    Zea mays (L.) is a crop widely cultivated throughout the world and can be considered suitable for phytomanagement due to its metal resistance and energetic value. In this study, the effect of two plant growth-promoting rhizobacteria, Ralstonia eutropha and Chryseobacterium humi, on growth and metal uptake of Z. mays plants in soils contaminated with up to 30 mg Cd kg(-1) was evaluated. Bacterial inoculation increased plant biomass up to 63% and led to a decrease of up to 81% in Cd shoot levels (4-88 mg Cd kg(-1)) and to an increase of up to 186% in accumulation in the roots (52-134 mg Cd kg(-1)). The rhizosphere community structure changed throughout the experiment and varied with different levels of Cd soil contamination, as revealed by molecular biology techniques. Z. mays plants inoculated with either of the tested strains may have potential application in a strategy of soil remediation, in particular short-term phytostabilization, coupled with biomass production for energy purposes.

  7. Uptake and effects of a mixture of widely used therapeutic drugs in Eruca sativa L. and Zea mays L. plants.

    Science.gov (United States)

    Marsoni, Milena; De Mattia, Fabrizio; Labra, Massimo; Bruno, Antonia; Bruno, Antonella; Bracale, Marcella; Vannini, Candida

    2014-10-01

    Pharmaceutically active compounds (PACs) are continuously dispersed into the environment due to human and veterinary use, giving rise to their potential accumulation in edible plants. In this study, Eruca sativa L. and Zea mays L. were selected to determine the potential uptake and accumulation of eight different PACs (Salbutamol, Atenolol, Lincomycin, Cyclophosphamide, Carbamazepine, Bezafibrate, Ofloxacin and Ranitidine) designed for human use. To mimic environmental conditions, the plants were grown in pots and irrigated with water spiked with a mixture of PACs at concentrations found in Italian wastewaters and rivers. Moreover, 10× and 100× concentrations of these pharmaceuticals were also tested. The presence of the pharmaceuticals was tested in the edible parts of the plants, namely leaves for E. sativa and grains for Z. mays. Quantification was performed by liquid chromatography mass spectroscopy (LC/MS/MS). In the grains of 100× treated Z. mays, only atenolol, lincomycin and carbamazepine were above the limit of detection (LOD). At the same concentration in E. sativa plants the uptake of all PACs was >LOD. Lincomycin and oflaxacin were above the limit of quantitation in all conditions tested in E. sativa. The results suggest that uptake of some pharmaceuticals from the soil may indeed be a potential transport route to plants and that these environmental pollutants can reach different edible parts of the selected crops. Measurements of the concentrations of these pharmaceuticals in plant materials were used to model potential adult human exposure to these compounds. The results indicate that under the current experimental conditions, crops exposed to the selected pharmaceutical mixture would not have any negative effects on human health. Moreover, no significant differences in the growth of E. sativa or Z. mays plants irrigated with PAC-spiked vs. non-spiked water were observed.

  8. Effect of metal tolerant plant growth promoting bacteria on growth and metal accumulation in Zea mays plants grown in fly ash amended soil.

    Science.gov (United States)

    Kumar, Kalpna V; Patra, D D

    2013-01-01

    The present study was undertaken to examine the effect of the application of fly ash (FA) into Garden soil (GS), with and without inoculation of plant growth promoting bacteria (PGPB), on the growth and metal uptake by Zea mays plants. Three FA tolerant PGPB strains, Pseudomonas sp. PS5, PS14, and Bacillus sp. BC29 were isolated from FA contaminated soils and assessed for their plant growth promoting features on the Z. mays plants. All three strains were also examined for their ability to solubilize phosphate and to produce Indole Acetic Acid (IAA), siderophores, and hydrogencynide acid (HCN) production. Although inoculation of all strains significantly enhanced the growth of plants at both the concentration of FA but maximum growth was observed in plants inoculated with BC29 and PS14 at low level (25%) of FA concentration. The experimental results explored the plant growth promoting features of selected strains which not only enhanced growth and biomass of plants but also protected them from toxicity of FA.

  9. ZnO nanoparticle fate in soil and zinc bioaccumulation in corn plants (Zea mays) influenced by alginate.

    Science.gov (United States)

    Zhao, Lijuan; Hernandez-Viezcas, Jose Angel; Peralta-Videa, Jose R; Bandyopadhyay, Susmita; Peng, Bo; Munoz, Berenice; Keller, Arturo A; Gardea-Torresdey, Jorge L

    2013-01-01

    Nanoparticles (NPs) can interact with naturally occurring inorganic and organic substances in soils, which may change their transport behavior in soil and plants. This study was performed in two steps. In the first step, corn (Zea mays) plants were cultivated for one month in soil amended with 10 nm commercial spheroid ZnO NPs at 0–800 mg kg−1 and sodium alginate at 10 mg kg−1. In the second step, the plants were grown with ZnO NPs at 400 mg kg−1 and alginate at 0, 10, 50, and 100 mg kg−1. The dynamics of Zn concentrations in soil solution and Zn accumulation in plant tissues were determined by ICP-OES. Biomass accumulation, chlorophyll concentration, and the activity of antioxidant enzymes in leaves were also quantified. Results indicate that ZnO NPs coexisting with Zn dissolved species were continuously released to the soil solution to replenish the Zn ions or ZnO NPs scavenged by roots. At 400 and 800 mg kg−1, without alginate, ZnO NPs significantly reduced the root and shoot biomass production; however, plants treated with these NP concentrations, plus alginate, had significantly more Zn in tissues with no reduction in biomass production. Alginate significantly reduced the activity of stress enzymes catalase and peroxidase, which could indicate damage in the defense system. The effects of ZnO NPs in a food crop grown in alginate enriched soil, showing an excess of Zn in the aerial parts, are yet to be reported.

  10. Effects of citrate-coated silver nanoparticles on interactions between soil bacteria and the major crop plant Zea mays

    Science.gov (United States)

    Doody, Michael; Bais, Harsh; Jin, Yan

    2014-05-01

    The increasing use of silver nanoparticles (AgNPs) in commercial antimicrobial products presents an opportunity for increased environmental exposures. While the behavior of AgNPs in surface waters is becoming increasingly understood, little research has been conducted on the effects of these, or any nanoparticles, on soil-dwelling bacteria and major crop plants. Because of the importance of soil bacteria to the overall health of natural and agricultural soils, it is necessary to better understand how AgNPs interact with common bacterial species such as Bacillus subtilis and Escherichia coli. It is further necessary to quantify the effect of AgNPs on major crop plants, including Zea mays, a staple crop for much of the world. Finally, research is needed on how complex plant-microbe interactions that originate in the rhizosphere may be disrupted by AgNPs. Our preliminary data show highly statistically significant growth inhibition near 30% for both species of bacteria exposed to 1.0 mg L-1 citrate-coated AgNPs (c-AgNPs). Growth curves compiled from absorbance data show a similar dose-response for both species. Treatment with aqueous Ag as AgNO3 slightly inhibits E. coli (90 ± 5 %), but enhances growth of B. subtilis to 127 ± 23% of control. These results indicate that toxicity may be related to specific nano-scale properties of the c-AgNPs. On-going experiments measure potential growth inhibition, root development and morphology of Z. mays exposed to c-AgNPs, and resulting changes in plant-microbe interactions.

  11. Antisense suppression of an acid invertase gene (MAI1) in muskmelon alters plant growth and fruit development.

    Science.gov (United States)

    Yu, Xiyan; Wang, Xiufeng; Zhang, Wenqian; Qian, Tingting; Tang, Guimin; Guo, Yankui; Zheng, Chengchao

    2008-01-01

    To unravel the roles of soluble acid invertase in muskmelon (Cucumis melo L.), its activity in transgenic muskmelon plants was reduced by an antisense approach. For this purpose, a 1038 bp cDNA fragment of muskmelon soluble acid invertase was expressed in antisense orientation behind the 35S promoter of the cauliflower mosaic virus. The phenotype of the antisense plants clearly differed from that of control plants. The transgenic plant leaves were markedly smaller, and the stems were obviously thinner. Transmission electron microscopy revealed that degradation of the chloroplast membrane occurred in transgenic leaves and the number of grana in the chloroplast was significantly reduced, suggesting that the slow growth and weaker phenotype of the transgenic plants may be due to damage to the chloroplast ultrastructure, which in turn resulted in a decrease in net photosynthetic rate. The sucrose concentration increased and levels of acid invertase decreased in transgenic fruit, and the fruit size was 60% smaller than that of the control. In addition, transgenic fruit reached full-slip at 25 d after pollination (DAP), approximately 5 d before the control fruit (full-slip at 30 DAP), and this accelerated maturity correlated with a dramatic elevation of ethylene production at the later stages of fruit development. Together, these results suggest that soluble acid invertase not only plays an important role during muskmelon plant and fruit development but also controls the sucrose content in muskmelon fruit.

  12. Effects of Zinc Deficiency and Drought on Plant Growth and Metabolism of Reactive Oxygen Species in Maize (Zea mays L.)

    Institute of Scientific and Technical Information of China (English)

    WANG Hong; JIN Ji-yun

    2007-01-01

    The combinative effects of applied zinc (Zn) and soil moisture on the plant growth, Zn uptake, and the metabolism of reactive oxygen species (ROS) in maize (Zea mays L.) plants were examined through two pot experiments under greenhouse conditions. Maize variety Zhongdan 9409 was used. In experiment 1, maize plants were grown in cumulic cinnamon soil with five Zn treatments (0, 3.0, 9.0, 27.0, and 81.0 mg Zn kg-1 soil). Three treatments of soil moisture including serious drought, mild drought, and adequate water supply were set at 30-35 %, 40-45 %, and 70-75 % (w/w) of soil saturated water content, respectively. Soil saturated water content was 36% (w/w). The dry matter weights of shoots were enhanced by Zn application and adequate water supply. There was no apparent difference in plant growth among Zn application rates from 3.0 to 81.0 mg Zn kg-1 soil. The increases of plant growth and Zn uptake due to Zn application were found more significant under well-watered condition than under drying condition. In experiment 2, two levels of Zn (0 and 5.0 mg Zn kg-1 soil) and soil moisture regimen (40-45 % and 70-75 % of soil saturated water content, respectively) were set. Zn deficiency or water stress resulted in higher concentrations of O2-· and malondiadehyde in the first fully expanded leaves.Zn deficiency lowered the activity of superoxide dismutase (SOD, EC 1.15.1.1) in leaves. Drought stress increased SOD activity in leaves regardless of Zn supply. The activity of guaiacol peroxidase (POD, EC1.11.1.11) was found to be enhanced by Zn supply only in well-watered leaves. Zinc deficiency or water stress had little effect on the activity of catalase (CAT, EC 1.11.1.6). The higher ROS level in early maize leaves due to water stress seemed not to be alleviated or lowered partially by Zn application. However, Zn fertilizer was recommended to apply to maize plants irrigated or supplied with adequate water, otherwise Zn deficiency would reduce the water use for plant biomass

  13. Isolation and identification of plant growth promoting rhizobacteria from maize (Zea mays L. rhizosphere and their plant growth promoting effect on rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Karnwal Arun

    2017-06-01

    Full Text Available The use of plant growth promoting rhizobacteria is increasing in agriculture and gives an appealing manner to replace chemical fertilizers, pesticides, and dietary supplements. The objective of our research was to access the plant growth promotion traits of Pseudomonas aeruginosa, P. fluorescens and Bacillus subtilis isolated from the maize (Zea mays L. rhizosphere. In vitro studies showed that isolates have the potential to produce indole acetic acid (IAA, hydrogen cyanide, phosphate solubilisation, and siderophore. RNA analysis revealed that two isolates were 97% identical to P. aeruginosa strain DSM 50071 and P. aeruginosa strain NBRC 12689 (AK20 and AK31, while two others were 98% identical to P. fluorescens strain ATCC 13525, P. fluorescens strain IAM 12022 (AK18 and AK45 and one other was 99% identical to B. subtilis strain NCDO 1769 (AK38. Our gnotobiotic study showed significant differences in plant growth variables under control and inoculated conditions. In the present research, it was observed that the isolated strains had good plant growth promoting effects on rice.

  14. Assessing the dynamic changes of rhizosphere functionality of Zea mays plants grown in organochlorine contaminated soils.

    Science.gov (United States)

    Blondel, Claire; Briset, Loïc; Legay, Nicolas; Arnoldi, Cindy; Poly, Franck; Clément, Jean-Christophe; Raveton, Muriel

    2017-06-05

    The persistent organochlorine pesticides (OCPs) in soils are suspected to disturb soil biogeochemical cycles. This study addressed the dynamic changes in soil functionality under lindane and chlordecone exposures with or without maize plant. Decreases in soil ammonium concentration, potential nitrogen mineralization and microbial biomass were only OCP-influenced in bulk soils. OCPs appeared to inhibit the ammonification step. With plants, soil functionality under OCP stress was similar to controls demonstrating the plant influence to ensure the efficiency of C- and N-turnover in soils. Moreover, OCPs did not impact the microbial community physiological profile in all tested conditions. However, microbial community structure was OCP-modified only in the presence of plants. Abundances of gram-negative and saprophytic fungi increased (up to +93% and +55%, respectively) suggesting a plant stimulation of nutrient turnover and rhizodegradation processes. Nevertheless, intimate microbial/plant interactions appeared to be OCP-impacted with depletions in mycorrhizae and micro/meso-fauna abundances (up to -53% and -56%, respectively) which might have adverse effects on more long-term plant growth (3-4 months). In short-term experiment (28days), maize growth was similar to the control ones, indicating an enhanced plasticity of the soil functioning in the presence of plants, which could efficiently participate to the remediation of OCP-contaminated soils. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Dynamic analysis of QTL for plant height at different developmental stages in maize (Zea mays L.)

    Institute of Scientific and Technical Information of China (English)

    YAN Jianbing; TANG Hua; HUANG Yiqin; SHI Yonggang; LI Jiansheng; ZHENG Yonglian

    2003-01-01

    Plant height in maize is not only one of important agronomic traits, but also one of model traits suitablefor study of developmental biology. Using data from fieldtests in two locations (Wuhan and Xiangfan) within the sameyear and a molecular linkage map covering all of 10 chro-mosomes, QTLs affecting plant height at five different de-velopmental stages were mapped and analyzed by the com-bination of composite interval mapping and the conditionalanalysis method. Eight QTLs for plant height at differentstages were located at different regions of five chromosomes(LOD≥2.5). The results showed that there were differenteffect values of QTL on plant height at different develop-mental stages. Three QTLs were detected at all of five stages.With different stages, contributory percentage of single QTL to plant height varied between 3.8% and 17.1%. It suggestedthat the expression of each QTL controlling plant height wasdifferent at different stages. With net growth, seven condi-tional QTLs for plant height were detected. Conditional QTLs were nearly detected at each stage, and QTLs of Ph1-1, Ph1-2, Ph3, Ph5-2 and Ph9 were detected at both locations (Wuhan and Xiangfan). The contributory percentage of single conditional QTL to plant height varied between 3.8% and 12.3%, indicating that QTLs for plant height are expressed in different time-space. Therefore, QTL expressed at different stages should be considered when marker assistant selection is conducted for quantitative traits.

  16. Avaliação do comportamento agronômico da planta e valor nutritivo da silagem de diferentes híbridos de milho (Zea mays, L. Evaluation of the agronomic behavior of the plant and nutritive value of silage from different corn (Zea mays, L. hybrids

    Directory of Open Access Journals (Sweden)

    Joilmaro Rodrigo Pereira Rosa

    2004-04-01

    Full Text Available O experimento foi desenvolvido com o objetivo de avaliar o comportamento agronômico produtivo da planta e as características químico-bromatológicas e fermentativas da silagem de diferentes híbridos de milho (Zea mays, L.: Agroceres AG-5011, Braskalb XL-344 e Cargill C-806. Para as avaliações agronômicas dos híbridos, utilizou-se o delineamento experimental inteiramente casualizado e, para a avaliação das silagens, o delineamento de blocos ao acaso, sendo o critério de bloqueamento o período de utilização da silagem. O híbrido C-806 foi o mais precoce, com intervalo de 100 dias da semeadura à colheita para ensilagem, enquanto o híbrido XL-344 foi o mais tardio, com intervalo de 121 dias. As características fenotípicas da planta de milho determinaram o potencial produtivo dos híbridos, tendo o híbrido AG-5011 apresentado a maior altura de planta e potencial produtivo de matéria verde e matéria seca por hectare, em relação aos híbridos C-806 e XL-344. Verificou-se, nos híbridos AG-5011 e C-806, maior população final de plantas em relação ao híbrido XL-344. O híbrido C-806 apresentou menor proporção de grãos em relação à planta inteira. Com base nos teores de MS e DIVMS, as silagens dos híbridos AG-5011, C-806 e XL-344 são classificadas como de boa qualidade. Com relação às características fermentativas, N-NH3/NT e pH, as silagens dos três híbridos são classificadas como de muito boa qualidade.The experiment was conducted with the objective to evaluate the agronomic production behavior of the plant and the chemical, qualitative and fermentation characteristics of silage from different corn (Zea mays, L. hybrids: Agroceres AG-5011, Braskalb XL-344 and Cargill C-806. For the agronomic behavior of the hybrids a complete randomized experimental design was used, and for silages evaluation a randomized block design was used, where the silage utilization period was the blocking criterion. C-806 hybrid was

  17. Cre/lox-mediated marker gene excision in transgenic maize (Zea mays L.) plants.

    Science.gov (United States)

    Zhang, W; Subbarao, S; Addae, P; Shen, A; Armstrong, C; Peschke, V; Gilbertson, L

    2003-11-01

    After the initial transformation and tissue culture process is complete, selectable marker genes, which are used in virtually all transformation approaches, are not required for the expression of the gene of interest in the transgenic plants. There are several advantages to removing the selectable marker gene after it is no longer needed, such as enabling the reuse of selectable markers and simplifying transgene arrays. We have tested the Cre/ lox system from bacteriophage P1 for its ability to precisely excise stably integrated marker genes from chromosomes in transgenic maize plants. Two strategies, crossing and autoexcision, have been tested and demonstrated. In the crossing strategy, plants expressing the Cre recombinase are crossed with plants bearing a transgene construct in which the selectable marker gene is flanked by directly repeated lox sites. Unlike previous reports in which incomplete somatic and germline excision were common, in our experiments complete somatic and germline marker gene excision occurred in the F(1) plants from most crosses with multiple independent Cre and lox lines. In the autoexcision strategy, the cre gene, under the control of a heat shock-inducible promoter, is excised along with the nptII marker gene. Our results show that a transient heat shock treatment of primary transgenic callus is sufficient for inducing cre and excising the cre and nptII genes. Genetic segregation and molecular analysis confirmed that marker gene removal is precise, complete and stable. The autoexcision strategy provides a way of removing the selectable marker gene from callus or other tissues such as embryos and kernels.

  18. TOR pathway activation in Zea mays L. tissues: conserved function between animal and plant kingdoms.

    Science.gov (United States)

    Garrocho-Villegas, Verónica; de Jiménez, Estela Sánchez

    2012-06-01

    In most non-photosynthetic eukaryotes it has been demonstrated a conserved signal transduction pathway, namely TOR-S6K, that coordinates growth and cell proliferation. This pathway targets the translational apparatus to induce selective translation of ribosomal mRNAs as well as stimulate the cell cycle transition through the G1/S phase. Thus, by activation of this pathway through environmental signals, nutrients, stress, or specific growth factors, such as insulin or insulin-like growth factors (IGF), this pathway allows organisms to regulate growth and cell division. In plants, evidence has shown that TOR protein has been highly conserved through evolution, being involved in growth and cell proliferation control as well. Particularly in maize, a peptide named ZmIGF has been found in actively growing tissues. It targets the maize TOR pathway at the same extent as insulin and, by doing so it induces growth, as well as ribosomal proteins and DNA synthesis. Thus, higher metazoans and plants seem to conserve similar biochemical paths to regulate cell growth through equivalent targets that conduce to activation of the TOR-S6K pathway. Recent research shows evidence that supports this proposal by uncovering the ZmIGF receptor in maize, providing further means for analyzing the role of the conserved TOR signaling pathway in this plant.

  19. Estimation of number and density, and random distribution testing of important plant species in Ban Pong Forest, Sansai District, Chiang Mai Province, Thailand using T-Square sampling

    Directory of Open Access Journals (Sweden)

    Phahol Sakkatat

    Full Text Available A study by T-square sampling method was conducted to investigate importantplant species in Ban Pong Forest, Sansai district, Chiang Mai province by estimation of theirnumber and density, and testing of their random distribution. The result showed that, therewere 14 kinds of important plant species, viz. Dipterocarpus tuberculatus Roxb., Shoreaobtuse Wall. exBlume, Bridelia retusa (L. A. Juss, Derris scandens Benth., Thysostachyssiamensis, Parinari anamense Hance, Vitex pinnata L.f., Canarium subulatum Guill.,Litsea glutinosa C.B.Roxb., Alphonsea glabrifolia Craib., Pueraria mirifica, Vaticastapfiana van Slooten, Walsura robusta Rox. and Dipterocarpus alatus Roxb. By far,Dipterocarpus tuberculatus Roxb was greatest in number and density, and all of the specieshad random distribution, except Walsura robusta Roxb and Dipterocarpus alatus Roxb

  20. Isolation and Identification of Indigenous Plant Growth Promoting Rhizobacteria from Himalayan Region of Kashmir and their Effect on Improving Growth and Nutrient Contents of Maize (Zea Mays L.

    Directory of Open Access Journals (Sweden)

    Mahwish eZahid

    2015-03-01

    Full Text Available IIntroduction and exploitation of plant growth promoting rhizobacteria (PGPR in agro-ecosystems enhance plant-microbes interactions that may affect ecosystems sustainability, agricultural productivity and environmental quality. The present study was conducted to isolate and identify PGPRs associated with maize (Zea mays L. from twenty sites of Himalayan region of Hajira-Rawalakot, Azad Jammu and Kashmir (AJK, Pakistan. A total of one hundred isolates were isolated from these sites, out of which eight (HJR1, HJR2, HJR3, HJR4, HJR5, MR6, HJR7, HJR8 were selected in vitro for their plant growth promoting ability (PGPA including phosphorus solubilization, indole acetic acid (IAA production and N2 fixation. The 16S rRNA gene sequencing technique was used for molecular identity and authentication. Isolates were then further tested for their effects on growth and nutrient contents of maize (Zea mays L. under pouch and pot conditions. The 16S rRNA gene sequencing and phylogenetic analysis identified these isolates belong to Pseudomonas and Bacillus genera. The isolates promoted plant growth by solubilizing soil P which ranged between 19.2 and 35.6 µgmL−1. The isolates HJR1, HJR2, HJR3 and HJR5 showed positive activity in acetylene reduction assay showing their N2-fixation potential. All eight isolates showed the potential to produce IAA in the range of 0.9−5.39 µgmL−1 and promote plant growth. Results from a subsequent pot experiment indicated PGPRs distinctly increased maize shoot and root length, shoot and root dry weight, root surface area, leaf surface area, shoot and root N and P contents. Among the eight isolates, HR3 showed a marked P-solubilizing activity, plant growth-promoting attributes, and the potential to be developed as a biofertilizers for integrated nutrient management strategies

  1. Striga parasitizes transgenic hairy roots of Zea mays and provides a tool for studying plant-plant interactions

    Science.gov (United States)

    2012-01-01

    Background Striga species are noxious root hemi-parasitic weeds that debilitate cereal production in sub-Saharan Africa (SSA). Control options for Striga are limited and developing Striga resistant crop germplasm is regarded as the best and most sustainable control measure. Efforts to improve germplasm for Striga resistance by a non-Genetic Modification (GM) approach, for example by exploiting natural resistance, or by a GM approach are constrained by limited information on the biological processes underpinning host-parasite associations. Additionaly, a GM approach is stymied by lack of availability of candidate resistance genes for introduction into hosts and robust transformation methods to validate gene functions. Indeed, a majority of Striga hosts, the world’s most cultivated cereals, are recalcitrant to genetic transformation. In maize, the existing protocols for transformation and regeneration are tedious, lengthy, and highly genotype-specific with low efficiency of transformation. Results We used Agrobacterium rhizogenes strain K599 carrying a reporter gene construct, Green Fluorescent Protein (GFP), to generate transgenic composite maize plants that were challenged with the parasitic plant Striga hermonthica. Eighty five percent of maize plants produced transgenic hairy roots expressing GFP. Consistent with most hairy roots produced in other species, transformed maize roots exhibited a hairy root phenotype, the hallmark of A. rhizogenes mediated transformation. Transgenic hairy roots resulting from A. rhizogenes transformation were readily infected by S. hermonthica. There were no significant differences in the number and size of S. hermonthica individuals recovered from either transgenic or wild type roots. Conclusions This rapid, high throughput, transformation technique will advance our understanding of gene function in parasitic plant-host interactions. PMID:22720750

  2. Striga parasitizes transgenic hairy roots of Zea mays and provides a tool for studying plant-plant interactions

    Directory of Open Access Journals (Sweden)

    Runo Steven

    2012-06-01

    Full Text Available Abstract Background Striga species are noxious root hemi-parasitic weeds that debilitate cereal production in sub-Saharan Africa (SSA. Control options for Striga are limited and developing Striga resistant crop germplasm is regarded as the best and most sustainable control measure. Efforts to improve germplasm for Striga resistance by a non-Genetic Modification (GM approach, for example by exploiting natural resistance, or by a GM approach are constrained by limited information on the biological processes underpinning host-parasite associations. Additionaly, a GM approach is stymied by lack of availability of candidate resistance genes for introduction into hosts and robust transformation methods to validate gene functions. Indeed, a majority of Striga hosts, the world’s most cultivated cereals, are recalcitrant to genetic transformation. In maize, the existing protocols for transformation and regeneration are tedious, lengthy, and highly genotype-specific with low efficiency of transformation. Results We used Agrobacterium rhizogenes strain K599 carrying a reporter gene construct, Green Fluorescent Protein (GFP, to generate transgenic composite maize plants that were challenged with the parasitic plant Striga hermonthica. Eighty five percent of maize plants produced transgenic hairy roots expressing GFP. Consistent with most hairy roots produced in other species, transformed maize roots exhibited a hairy root phenotype, the hallmark of A. rhizogenes mediated transformation. Transgenic hairy roots resulting from A. rhizogenes transformation were readily infected by S. hermonthica. There were no significant differences in the number and size of S. hermonthica individuals recovered from either transgenic or wild type roots. Conclusions This rapid, high throughput, transformation technique will advance our understanding of gene function in parasitic plant-host interactions.

  3. Atividade de glutationa S-transferase na degradação do herbicida glyphosate em plantas de milho (Zea mays Glutathione S-transferase activity on the degradation of the herbicide glyphosate in maize (Zea mays plants

    Directory of Open Access Journals (Sweden)

    A.C. Cataneo

    2003-08-01

    Full Text Available A glutationa S-transferase (GST, EC 2.5.1.18 desempenha um papel importante na resposta do estresse causado por herbicidas nas plantas; é considerada uma enzima de desintoxicação, por metabolizar grande variedade de compostos xenobióticos, por meio da conjugação destes com glutationa reduzida, formando substâncias de baixa toxicidade. O milho (Zea mays foi escolhido neste trabalho por apresentar problemas de injúrias quando submetido ao controle químico de plantas daninhas, por meio do uso de herbicidas. Esta pesquisa teve como objetivo determinar as alterações na atividade desta enzima em plantas de milho submetidas ao tratamento pelo herbicida glyphosate. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 4x4, com quatro tratamentos herbicidas (glyphosate nas concentrações de 1.000, 2.500 e 5.000 ppm e as plantas-controle tratadas com água e quatro estádios de desenvolvimento (9, 16, 23 e 30 dias após a emergência, com cinco repetições. O herbicida foi aplicado na parte aérea das plântulas de milho. A parte aérea foi coletada às 24, 48 e 72 horas após a aplicação do herbicida e utilizada para a determinação da atividade da GST e do teor de lipoperóxidos. Foi verificado que os teores de lipoperóxidos não foram alterados pelo tratamento com o glyphosate, porém a atividade de GST aumentou na maioria dos tratamentos utilizados, indicando ter ação na degradação do herbicida glyphosate em plantas de milho.Glutathione S-transferase (GST, EC 2.5.1.18 plays an important role in the response to stress caused by herbicides in plants; it is considered to be a detoxifying enzyme since it metabolizes a great variety of xenobiotic compounds, by combining them with reduced glutathione, forming substances of low toxicity. Maize (Zea mays was chosen in this work for showing injury problems when submitted to weed chemical control. This research aimed to determine the alterations in the

  4. Stem characteristics of two forage maize (Zea mays L.) cultivars varying in whole plant digestibility. III. Intra-stem variability in anatomy, chemical composition and in vitro rumen fermentation

    NARCIS (Netherlands)

    Boon, E.J.M.C.; Struik, P.C.; Tamminga, S.; Engels, F.M.; Cone, J.W.

    2008-01-01

    The internodes of forage maize (Zea mays L.) stems were studied at anthesis for variation in anatomy and chemical composition in relation to digestibility. The study was carried out with a short (Vitaro) and a tall (Volens) cultivar differing in whole-plant digestibility, both of which were grown in

  5. Differential antimicrobial activity of silver nanoparticles to bacteria Bacillus subtilis and Escherichia coli, and toxicity to crop plant Zea mays and beneficial B. subtilis-inoculated Z. mays

    Science.gov (United States)

    Doody, Michael A.; Wang, Dengjun; Bais, Harsh P.; Jin, Yan

    2016-10-01

    As silver nanoparticles (AgNPs) have become increasingly used in commercial antimicrobial agents and industrial and military products, concerns are increasing over their broad environmental and health impacts and risks because they are finding their way to the environment. This study was designed to quantify the antimicrobial activity of citrate-coated AgNPs (c-AgNPs; transmission electron microscope size of 44.9 ± 7.2 nm) to two species of bacteria, i.e., Gram-positive Bacillus subtilis and Gram-negative Escherichia coli, and toxicity to a major crop plant Zea mays and beneficial bacteria-inoculated plant (i.e., B. subtilis-inoculated Z. mays symbiont). Our results reveal that the exposure of c-AgNPs significantly inhibited bacteria growth and altered their growth kinetics. Z. mays experienced significant sublethal effects including reduced root length and biomass, and hyper-accumulation of Ag in roots. The beneficial interactions between B. subtilis and Z. mays were weakened as well because both species suffered sublethal effects. Potential mechanisms leading to the antimicrobial activity and toxicity of c-AgNPs to the bacteria, plant, and plant-bacteria symbiont examined in this study were discussed. Taken together, our findings advance the current knowledge of AgNPs antimicrobial property or toxicity to bacteria, crop plant, and beneficial plant-bacteria symbiotic interaction, which is a critical component for NPs environmental impact and risk assessment.

  6. Effects of municipal solid waste compost and mineral fertilizer amendments on soil properties and heavy metals distribution in maize plants (Zea mays L.).

    Science.gov (United States)

    Carbonell, Gregoria; de Imperial, Rosario Miralles; Torrijos, Manuel; Delgado, Mar; Rodriguez, José Antonio

    2011-11-01

    Soil amendments based on crop nutrient requirements are considered a beneficial management practice. A greenhouse experiment with maize seeds (Zea mays L.) was conducted to assess the inputs of metals to agricultural land from soil amendments. Maize seeds were exposed to a municipal solid waste (MSW) compost (50 Mg ha(-1)) and NPK fertilizer (33 g plant(-1)) amendments considering N plant requirement until the harvesting stage with the following objectives: (1) determine the accumulation of total and available metals in soil and (2) know the uptake and ability of translocation of metals from roots to different plant parts, and their effect on biomass production. The results showed that MSW compost increased Cu, Pb and Zn in soil, while NPK fertilizer increased Cd and Ni, but decreased Hg concentration in soil. The root system acted as a barrier for Cr, Ni, Pb and Hg, so metal uptake and translocation were lower in aerial plant parts. Biomass production was significantly enhanced in both MSW and NPK fertilizer-amended soils (17%), but also provoked slight increases of metals and their bioavailability in soil. The highest metal concentrations were observed in roots, but there were no significant differences between plants growing in amended soil and the control soil. Important differences were found for aerial plant parts as regards metal accumulation, whereas metal levels in grains were negligible in all the treatments.

  7. Regulation of plasma membrane aquaporins by inoculation with a Bacillus megaterium strain in maize (Zea mays L.) plants under unstressed and salt-stressed conditions.

    Science.gov (United States)

    Marulanda, Adriana; Azcón, Rosario; Chaumont, François; Ruiz-Lozano, Juan Manuel; Aroca, Ricardo

    2010-07-01

    It is documented that some plant-growth-promoting rhizobacteria (PGPR) enhance plant salt tolerance. However, as to how PGPR may influence two crucial components of plant salt tolerance such as, root hydraulic characteristics and aquaporin regulation has been almost unexplored. Here, maize (Zea mays L.) plants were inoculated with a Bacillus megaterium strain previously isolated from a degraded soil and characterized as PGPR. Inoculated plants were found to exhibit higher root hydraulic conductance (L) values under both unstressed and salt-stressed conditions. These higher L values in inoculated plants correlated with higher plasma membrane type two (PIP2) aquaporin amount in their roots under salt-stressed conditions. Also, ZmPIP1;1 protein amount under salt-stressed conditions was higher in inoculated leaves than in non-inoculated ones. Hence, the different regulation of PIP aquaporin expression and abundance by the inoculation with the B. megaterium strain could be one of the causes of the different salt response in terms of root growth, necrotic leaf area, leaf relative water content and L by the inoculation treatment.

  8. ACARI, CIDADE (MAIS) LIMPA

    OpenAIRE

    Maria Luiza de Medeiros Galvão

    2013-01-01

    Este trabalho tem por objetivo realizar uma breve reflexão acerca da concepção empírica de Acari como a cidade mais limpa do Brasil, assim referenciada na década de 70 do século XX. Como introdução, desenvolvemos considerações iniciais sobre cidade, tendo como recurso metodológico os conhecimentos adquiridos com a disciplina Arquitetura e Cidade no Brasil. Dando sequência ao texto, refletimos conceitualmente sobre cidade, espaço balizador para compreensão de Acari - cidade mais limpa; territó...

  9. Saateks albumile / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2000-01-01

    Eesti Kunstimuuseumi väljaandest "Kadrioru lossi aarded". Koostajad Anu Allikvee, Tiina-Mall Kreem, Kersti Kuldna, Jüri Kuuskemaa, Mai Levin, Kadi Polli, Anneli Randla, eessõna Jüri Kuuskemaa, toimetaja Anneli Randla, fotod Peeter Säre, Stanislav Stepashko, Boris Mäemets, kujundus Irina Tammis

  10. Saateks albumile / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2000-01-01

    Eesti Kunstimuuseumi väljaandest "Kadrioru lossi aarded". Koostajad Anu Allikvee, Tiina-Mall Kreem, Kersti Kuldna, Jüri Kuuskemaa, Mai Levin, Kadi Polli, Anneli Randla, eessõna Jüri Kuuskemaa, toimetaja Anneli Randla, fotod Peeter Säre, Stanislav Stepashko, Boris Mäemets, kujundus Irina Tammis

  11. ACARI, CIDADE (MAIS LIMPA

    Directory of Open Access Journals (Sweden)

    Maria Luiza Medeiros Galvão

    2013-10-01

    Full Text Available Este trabalho tem por objetivo realizar uma breve reflexão acerca da concepção empírica de Acari como a cidade mais limpa do Brasil, assim referenciada na década de 70 do século XX. Como introdução, desenvolvemos considerações iniciais sobre cidade, tendo como recurso metodológico os conhecimentos adquiridos com a disciplina Arquitetura e Cidade no Brasil. Dando sequência ao texto, refletimos conceitualmente sobre cidade, espaço balizador para compreensão de Acari - cidade mais limpa; território, para compreensão da cidade como construção histórica; e o Ambiente, cujo propósito foi associar o tema do trabalho à sustentabilidade socioambiental. Utilizamos dois contextos: o primeiro de crise e divulgação do título cidade mais limpa. O segundo, dizendo respeito à legislação urbanística e códigos de postura elaborados nos períodos imperial e republicano, que ordenaram o território de Acari nos dois últimos séculos, marcando a tradição de asseio, limpeza e higiene urbanas.

  12. Inoculation with the plant-growth-promoting rhizobacterium Azospirillum brasilense causes little disturbance in the rhizosphere and rhizoplane of maize (Zea mays).

    Science.gov (United States)

    Herschkovitz, Yoav; Lerner, Anat; Davidov, Yaacov; Rothballer, Michael; Hartmann, Anton; Okon, Yaacov; Jurkevitch, Edouard

    2005-08-01

    Inoculation with Azospirillum brasilense exerts beneficial effects on plant growth and crop yields. In this study, a comparative analysis of maize (Zea mays) root inoculated or not inoculated with A. brasilense strains was performed in two soils. Colonization dynamics of the rhizobacteria were tracked in various root compartments using 16S rRNA-targeted probes and 4',6'diamidino-2-phenylindole staining, and the structure of bacterial populations in the same samples was analyzed by denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction products of the 16S rRNA gene. Based on whole cell hybridization, a large fraction of the bacterial community was found to be active in both the rhizoplane-endorhizosphere and rhizosphere soil compartments, in both soil types. A DGGE fingerprint analysis revealed that plant inoculation with A. brasilense had no effect on the structural composition of the bacterial communities, which were also found to be very similar at the root tip and at zones of root branching. However, rhizobacterial populations were strongly influenced by plant age, and their complexity decreased in the rhizoplane-endorhizosphere in comparison to rhizosphere soil. A clone library generated from rhizosphere DNA revealed a highly diverse community of soil and rhizosphere bacteria, including an indigenous Azospirillum-like organism. A large proportion of these clones was only distantly related to known species.

  13. Contrasting effects of biochar, compost and farm manure on alleviation of nickel toxicity in maize (Zea mays L.) in relation to plant growth, photosynthesis and metal uptake.

    Science.gov (United States)

    Rehman, Muhammad Zia-Ur; Rizwan, Muhammad; Ali, Shafaqat; Fatima, Nida; Yousaf, Balal; Naeem, Asif; Sabir, Muhammad; Ahmad, Hamaad Raza; Ok, Yong Sik

    2016-11-01

    Nickel (Ni) toxicity in agricultural crops is a widespread problem while little is known about the role of biochar (BC) and other organic amendments like farm manure (FM) from cattle farm and compost (Cmp) on its alleviation. A greenhouse experiment was conducted to evaluate the effects of BC, Cmp and FM on physiological and biochemical characteristics of maize (Zea mays L.) under Ni stress. Maize was grown in Ni spiked soil without and with two rates of the amendments (equivalent to 1% and 2% organic carbon, OC) applied separately to the soil. After harvest, plant height, root length, dry weight, chlorophyll contents, gas exchange characteristics and trace elements in plants were determined. In addition, post-harvest soil characteristics like pHs, ECe and bioavailable Ni were also determined. Compared to the control, all of the amendments increased plant height, root length, shoot and root dry weight with the maximum increase in all parameters by FM (2% OC) treatment. Similarly, total chlorophyll contents and gas exchange characteristics significantly increased with the application of amendments being maximum with FM (2% OC) application. Amendments significantly increased copper, zinc, manganese and iron concentrations and decreased Ni concentrations in the plants. The highest reduction in shoot Ni concentration was recorded with FM (2% OC) followed by BC (2% OC) being 73.2% and 61.1% lower compared to the control, respectively. The maximum increase in soil pH and decrease in AB-DTPA extractable Ni was recorded with BC (2% OC) followed by FM (2% OC). It is concluded that FM (2% OC) was the most effective in reducing Ni toxicity to plants by reducing Ni uptake while BC (2% OC) was the most effective in decreasing bioavailable Ni in the soil through increasing soil pH. However, long-term field studies are needed to evaluate the effects of these amendments in reducing Ni toxicity in plants. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Isolation and identification of indigenous plant growth promoting rhizobacteria from Himalayan region of Kashmir and their effect on improving growth and nutrient contents of maize (Zea mays L.).

    Science.gov (United States)

    Zahid, Mahwish; Abbasi, M Kaleem; Hameed, Sohail; Rahim, Nasir

    2015-01-01

    Introduction and exploitation of plant growth promoting rhizobacteria (PGPR) in agro-ecosystems enhance plant-microbes interactions that may affect ecosystems sustainability, agricultural productivity, and environmental quality. The present study was conducted to isolate and identify PGPRs associated with maize (Zea mays L.) from twenty sites of Himalayan region of Hajira-Rawalakot, Azad Jammu and Kashmir (AJK), Pakistan. A total of 100 isolates were isolated from these sites, out of which eight (HJR1, HJR2, HJR3, HJR4, HJR5, MR6, HJR7, HJR8) were selected in vitro for their plant growth promoting ability (PGPA) including phosphorus solubilization, indole-3-acetic acid (IAA) production and N2 fixation. The 16S rRNA gene sequencing technique was used for molecular identity and authentication. Isolates were then further tested for their effects on growth and nutrient contents of maize (Z. mays L.) under pouch and pot conditions. The 16S rRNA gene sequencing and phylogenetic analysis identified these isolates belong to Pseudomonas and Bacillus genera. The isolates promoted plant growth by solubilizing soil P which ranged between 19.2 and 35.6 μg mL(-1). The isolates HJR1, HJR2, HJR3, and HJR5 showed positive activity in acetylene reduction assay showing their N2-fixation potential. All eight isolates showed the potential to produce IAA in the range of 0.9-5.39 μg mL(-1) and promote plant growth. Results from a subsequent pot experiment indicated PGPRs distinctly increased maize shoot and root length, shoot and root dry weight, root surface area, leaf surface area, shoot and root N and P contents. Among the eight isolates, HR3 showed a marked P-solubilizing activity, plant growth-promoting attributes, and the potential to be developed as a biofertilizers for integrated nutrient management strategies.

  15. Promotion of growth and Cu accumulation of bio-energy crop (Zea mays) by bacteria: implications for energy plant biomass production and phytoremediation.

    Science.gov (United States)

    Sheng, Xiafang; Sun, Leni; Huang, Zhi; He, Linyan; Zhang, Wenhui; Chen, Zhaojin

    2012-07-30

    Three metal-resistant and plant growth-promoting bacteria (Burkholderia sp. GL12, Bacillus megaterium JL35 and Sphingomonas sp. YM22) were evaluated for their potential to solubilize Cu(2) (OH)(2)CO(3) in solution culture and their plant growth promotion and Cu uptake in maize (Zea mays, an energy crop) grown in a natural highly Cu-contaminated soil. The impacts of the bacteria on the Cu availability and the bacterial community in rhizosphere soils of maize were also investigated. Inductively coupled-plasma optical emission spectrometer analysis showed variable amounts of water-soluble Cu (ranging from 20.5 to 227 mgL(-1)) released by the bacteria from Cu(2) (OH)(2)CO(3) in solution culture. Inoculation with the bacteria was found to significantly increase root (ranging from 48% to 83%) and above-ground tissue (ranging from 33% to 56%) dry weights of maize compared to the uninoculated controls. Increases in Cu contents of roots and above-ground tissues varied from 69% to 107% and from 16% to 86% in the bacterial-inoculated plants compared to the uninoculated controls, respectively. Inoculation with the bacteria was also found to significantly increase the water-extractive Cu concentrations (ranging from 63 to 94%) in the rhizosphere soils of the maize plants compared to the uninoculated controls in pot experiments. Denaturing gradient gel electrophoresis and sequence analyses showed that the bacteria could colonize the rhizosphere soils and significantly change the bacterial community compositions in the rhizosphere soils. These results suggest that the metal-resistant and plant growth-promoting bacteria may be exploited for promoting the maize (energy crop) biomass production and Cu phytoremediation in a natural highly Cu-contaminated soil. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Influence of sub-lethal crude oil concentration on growth, water relations and photosynthetic capacity of maize (Zea mays L.) plants.

    Science.gov (United States)

    Athar, Habib-Ur-Rehman; Ambreen, Sarah; Javed, Muhammad; Hina, Mehwish; Rasul, Sumaira; Zafar, Zafar Ullah; Manzoor, Hamid; Ogbaga, Chukwuma C; Afzal, Muhammad; Al-Qurainy, Fahad; Ashraf, Muhammad

    2016-09-01

    Maize tolerance potential to oil pollution was assessed by growing Zea mays in soil contaminated with varying levels of crude oil (0, 2.5 and 5.0 % v/w basis). Crude oil contamination reduced soil microflora which may be beneficial to plant growth. It was observed that oil pollution caused a remarkable decrease in biomass, leaf water potential, turgor potential, photosynthetic pigments, quantum yield of photosystem II (PSII) (Fv/Fm), net CO2 assimilation rate, leaf nitrogen and total free amino acids. Gas exchange characteristics suggested that reduction in photosynthetic rate was mainly due to metabolic limitations. Fast chlorophyll a kinetic analysis suggested that crude oil damaged PSII donor and acceptor sides and downregulated electron transport as well as PSI end electron acceptors thereby resulting in lower PSII efficiency in converting harvested light energy into biochemical energy. However, maize plants tried to acclimate to moderate level of oil pollution by increasing root diameter and root length relative to its shoot biomass, to uptake more water and mineral nutrients.

  17. Helicoverpa zea CYP6B8 and CYP321A1: different molecular solutions to the problem of metabolizing plant toxins and insecticides.

    Science.gov (United States)

    Rupasinghe, Sanjeewa G; Wen, Zhimou; Chiu, Ting-Lan; Schuler, Mary A

    2007-12-01

    Under continual exposure to naturally occurring plant toxins and synthetic insecticides, insects have evolved cytochrome P450 monooxygenases (P450s) capable of metabolizing a wide range of structurally different compounds. Two such P450s, CYP6B8 and CYP321A1, expressed in Helicoverpa zea (a lepidopteran) in response to plant allelochemicals and plant signaling molecules metabolize these compounds with varying efficiencies. While sequence alignments of these proteins indicate highly divergent substrate recognition sites (SRSs), homology models developed for them indicate that the two active site cavities have essentially the same volume with distinct shapes dictated by side-chain differences in SRS1 and SRS5. CYP6B8 has a narrower active site cavity extending from substrate access channel pw2a with a very narrow access to the ferryl oxygen atom. This predicted shape suggests that bulkier molecules bind further from the ferryl oxygen at positions that are not as effectively metabolized. In contrast, CYP321A1 is predicted to have a more spacious cavity allowing larger molecules to access the heme-bound oxygen. The metabolic profiles for several plant toxins (xanthotoxin, angelicin) and insecticides (cypermethrin, aldrin and diazinon) correlate well with these predictive models. The absence of Thr in the I helix of CYP321A1 and hydroxyl groups on many of its substrates suggests that this insect P450 mediates oxygen activation by a mechanism different from that employed by CYP107A1 and CYP158A1, which are two bacterial P450s also lacking Thr in their I helix, and most other P450s that contain Thr in their I helix.

  18. Diversity and characterization of culturable bacterial endophytes from Zea mays and their potential as plant growth-promoting agents in metal-degraded soils.

    Science.gov (United States)

    Pereira, S I A; Castro, P M L

    2014-12-01

    In this study, we evaluated the phylogenetic diversity of culturable bacterial endophytes of Zea mays plants growing in an agricultural soil contaminated with Zn and Cd. Endophytic bacterial counts were determined in roots and shoots, and isolates were grouped by random amplified polymorphic DNA and identified by 16S ribosomal RNA (rRNA) gene sequencing. Endophytes were further characterized for the production of plant growth-promoting (PGP) substances, such as NH3, siderophores, indol-3-acetic acid (IAA), hydrogen cyanide and extracellular enzymes, and for the capacity to solubilize phosphate. The endophytes producing higher amounts of IAA were screened for their tolerance to Zn and Cd and used as bioinoculants for maize seedlings grown in the Zn/Cd-contaminated soil. The counts of endophytes varied between plant tissues, being higher in roots (6.48 log10 g(-1) fresh weight) when compared to shoots (5.77 log10 g(-1) fresh weight). Phylogenetic analysis showed that endophytes belong to three major groups: α-Proteobacteria (31 %), γ-Proteobacteria (26 %) and Actinobacteria (26 %). Pseudomonas, Agrobacterium, Variovorax and Curtobacterium were among the most represented genera. Endophytes were well-adapted to high Zn/Cd concentrations (up to 300 mg Cd l(-1) and 1,000 mg Zn l(-1)) and showed ability to produce several PGP traits. Strains Ochrobactrum haematophilum ZR 3-5, Acidovorax oryzae ZS 1-7, Frigoribacterium faeni ZS 3-5 and Pantoea allii ZS 3-6 increased root elongation and biomass of maize seedlings grown in soil contaminated with Cd and Zn. The endophytes isolated in this study have potential to be used in bioremediation/phytoremediation strategies.

  19. The effect of different crop plant densities on radiation absorption and use efficiency by corn (Zea mays L. and bean (Phaseolus vulgaris L. intercropped canopy

    Directory of Open Access Journals (Sweden)

    L. Rostami

    2016-05-01

    Full Text Available In order to determinate the effects of plant densities in intercropped corn (Zea mays L. and bean (Phaseolus vulgaris L. on radiation absorption and use efficiency, an experiment was conducted at the Agricultural Research Station, Ferdowsi University of Mashhad, Iran during growing season of 2007-2008. This experiment was conducted in low input system. A randomized complete block design with three replications was used. Treatments were included bean intercropping with corn in normal density of bean plus 10%, 20% and 30% excess bean C (B+10%, C (B+20%, C (B+30%, increasing in density bean intercropping with corn in normal density of corn plus 10%, 20% and 30% excess corn B (C+10%, B (C+20%, B (C+30% and sole crops of corn (C and bean (B. Results indicated that leaf area index, radiation absorption, total dry matter and radiation use efficiency of corn increased in all intercropped treatments compared to sole cropping, but it reversed for bean. It seems that complementary and facilitative effects of intercropping were more for corn. Range of corn and bean radiation use efficiency was from 1.92 g.MJ-1 (in sole cropping and 0.72 g.MJ-1 {in (C+30% (B+30%} to 2.30 g.MJ-1 {in C (B+30%} and 1.45 g.MJ-1 (in sole cropping, respectively.

  20. The influence of microbial-based inoculants on N2O emissions from soil planted with corn (Zea mays L.) under greenhouse conditions with different nitrogen fertilizer regimens.

    Science.gov (United States)

    Calvo, Pamela; Watts, Dexter B; Kloepper, Joseph W; Torbert, H Allen

    2016-12-01

    Nitrous oxide (N2O) emissions are increasing at an unprecedented rate owing to the increased use of nitrogen (N) fertilizers. Thus, new innovative management tools are needed to reduce emissions. One potential approach is the use of microbial inoculants in agricultural production. In a previous incubation study, we observed reductions in N2O emissions when microbial-based inoculants were added to soil (no plants present) with N fertilizers under laboratory incubations. This present study evaluated the effects of microbial-based inoculants on N2O and carbon dioxide (CO2) emissions when applied to soil planted with corn (Zea mays L.) under controlled greenhouse conditions. Inoculant treatments consisted of (i) SoilBuilder (SB), (ii) a metabolite extract of SoilBuilder (SBF), and (iii) a mixture of 4 strains of plant-growth-promoting Bacillus spp. (BM). Experiments included an unfertilized control and 3 N fertilizers: urea, urea - ammonium nitrate with 32% N (UAN-32), and calcium - ammonium nitrate with 17% N (CAN-17). Cumulative N2O fluxes from pots 41 days after planting showed significant reductions in N2O of 15% (SB), 41% (BM), and 28% (SBF) with CAN-17 fertilizer. When UAN-32 was used, reductions of 34% (SB), 35% (SBF), and 49% (BM) were obtained. However, no reductions in N2O emissions occurred with urea. Microbial-based inoculants did not affect total CO2 emissions from any of the fertilized treatments or the unfertilized control. N uptake was increased by an average of 56% with microbial inoculants compared with the control (nonmicrobial-based treatments). Significant increases in plant height, SPAD chlorophyll readings, and fresh and dry shoot mass were also observed when the microbial-based treatments were applied (with and without N). Overall, results demonstrate that microbial inoculants can reduce N2O emissions following fertilizer application depending on the N fertilizer type used and can enhance N uptake and plant growth. Future studies are planned to

  1. Evaluation of protein pattern changes in roots and leaves of Zea mays plants in response to nitrate availability by two-dimensional gel electrophoresis analysis

    Directory of Open Access Journals (Sweden)

    Cocucci Maurizio

    2009-08-01

    Full Text Available Abstract Background Nitrogen nutrition is one of the major factors that limit growth and production of crop plants. It affects many processes, such as development, architecture, flowering, senescence and photosynthesis. Although the improvement in technologies for protein study and the widening of gene sequences have made possible the study of the plant proteomes, only limited information on proteome changes occurring in response to nitrogen amount are available up to now. In this work, two-dimensional gel electrophoresis (2-DE has been used to investigate the protein changes induced by NO3- concentration in both roots and leaves of maize (Zea mays L. plants. Moreover, in order to better evaluate the proteomic results, some biochemical and physiological parameters were measured. Results Through 2-DE analysis, 20 and 18 spots that significantly changed their amount at least two folds in response to nitrate addition to the growth medium of starved maize plants were found in roots and leaves, respectively. Most of these spots were identified by Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometry (LC-ESI-MS/MS. In roots, many of these changes were referred to enzymes involved in nitrate assimilation and in metabolic pathways implicated in the balance of the energy and redox status of the cell, among which the pentose phosphate pathway. In leaves, most of the characterized proteins were related to regulation of photosynthesis. Moreover, the up-accumulation of lipoxygenase 10 indicated that the leaf response to a high availability of nitrate may also involve a modification in lipid metabolism. Finally, this proteomic approach suggested that the nutritional status of the plant may affect two different post-translational modifications of phosphoenolpyruvate carboxylase (PEPCase consisting in monoubiquitination and phosphorylation in roots and leaves, respectively. Conclusion This work provides a first characterization of the proteome

  2. EFFECT OF DROUGHT STRESS INDUCED BY MANNITOL ON PHYSIOLOGICAL PARAMETERS OF MAIZE (ZEA MAYS L. SEEDLINGS AND PLANTS

    Directory of Open Access Journals (Sweden)

    Katarzyna Możdżeń

    2015-02-01

    Full Text Available Plants are exposed to various stress factors which might lead to structural damage and physiological function abnormalities. Drought is one of the environmental stress factors that reduce the productivity of plants. The aim of our study was to determine the influence of drought stress induced by mannitol (-0.5 and -1.5MPa on selected physiological processes in Z. mays L. In the first stage we studied the effect of mannitol on the germination. In the second stage the effect of mannitol on the growth of plants germinated on distilled water and watered with mannitol in growth phase were measured. Mannitol, which decreased the water content in a concentration-dependent manner, had an inhibitory effect on germination and growth of seedlings and adult plants. Electrolyte leakage of cell membranes of the Z. mays seedlings showed high disturbances in the functioning of the membrane structures in the osmotic drought conditions. Similar results were obtained for maize roots, shoots and leaves in both treatment studies. Chlorophyll content showed only significant differences in plants from treated during the growth phase. Drought stress caused a decrease in chlorophyll content by almost a half compared to the control plants. Measurements of chlorophyll fluorescence of plant leaves from the second stage of experiments showed changes in fluorescence activity parameters Fv/Fm, NPQ, Rfd, qP, ect.; gas exchange measurements also showed changes in activity in each of the two phases.

  3. EFFECT OF EXOGENOUS POLYAMINE DIETHYLENETRIAMINE ON OXIDATIVE CHANGES AND PHOTOSYNTHESIS IN AS-TREATED MAIZE PLANTS (Zea mays L.

    Directory of Open Access Journals (Sweden)

    N STOEVA

    2006-05-01

    Full Text Available The antioxidant effect of the exogenous polyamine Diethylentriamine (DETA on the oxidative changes in young maize plants treated with different As concentrations was studied. The plants were grown in a climatic box in a Hogland-Arnon nutrient solution. Arsenic was applied as Na3As04 in concentrations 0, 2 and 5 mg dm-3 (pH 5.5. The polyamine DETA (concentration 10-4 М was added to the nutrient environment of some of the plants 24 hours prior to the As treatment. Five days later the lipid peroxidation level, the peroxidase activity, the growth and leaf gasexchange, and the protein and plastid pigments content were studied. The physiological analyses proved that DETA had positive effect on the As-treated maize plants by increasing the leaf gas-exchange, the plastid pigments content and soluble protein. The exogenous polyamine DETA, applied 24 hours prior to the As treatment, decreased considerably the lipid peroxidation level and the peroxidase itself in maize plants. DETA had protective effect on the As-induced oxidative stress, but in order to clarify its role as an antioxidant, more detailed and profound studies should be made.

  4. Interactions between Fusarium verticillioides, Ustilago maydis, and Zea mays: an endophyte, a pathogen, and their shared plant host

    Science.gov (United States)

    Highly diverse communities of microbial symbionts occupy eukaryotic organisms, including plants. While many well-studied symbionts may be characterized as either parasites or as mutualists, the prevalent but cryptic endophytic fungi are less easily qualified because they do not cause observable symp...

  5. Impact of Cinnamic Acid on Physiological and Anatomical Changes in Maize Plants (Zea mays L. Grown under Salinity Stress

    Directory of Open Access Journals (Sweden)

    Pramod Kumar Singh

    2014-05-01

    Full Text Available The environmental contamination with high salt is the elementary intimidation to the agriculture. Maize plants were deeply affected due to salinity worldwide and a severe problem to scientists. A probable survival strategy of the plants under unpleasant environmental circumstances is to use of endogenous metabolites that could ameliorate the harsh effect of salinity. Current study was under taken to observe the effect of cinnamic acid (CA, a central molecule of phenylpropanoid pathway (Secondary metabolism on the growth and development of maize plants under NaCl stress conditions. CA is rapidly produced by plants in response to stressful condition. Response to maize seed to the presoaking treatment 0.05mM CA was deliberated under different concentration of NaCl stress such as 50, 100, 150, 200, mM NaCl for 14 days. The injurious effects of salinity on growth and development were manifested by decreased fresh weight, dry weight, and relative water content (RWC and chlorophyll pigment contents. Degree of lipid peroxidation turned down through the significant decrease in MDA content in maize seedlings. CA induced the anatomical properties under salinity .In present exploration. The cortical cells were induced in root in response to CA than stress. Here, the present study was undertaken with the aim of determining salt induced anatomical and morphological alteration in the presence of exogenous CA. The major reduction in dimension of cortical cells was observed which indicate that salt stress reduced the tolerance of cortical cell more than treatment in maize root. We conclude that CA is a potential phenylpyranoid for protecting crop plant under saline environment.

  6. Enzymes that control the thiamine diphosphate pool in plant tissues. Properties of thiamine pyrophosphokinase and thiamine-(di)phosphate phosphatase purified from Zea mays seedlings.

    Science.gov (United States)

    Rapala-Kozik, Maria; Gołda, Anna; Kujda, Marta

    2009-04-01

    The pool of thiamine diphosphate (TDP), available for TDP-dependent enzymes involved in the major carbohydrate metabolic pathways, is controlled by two enzyme systems that act in the opposite directions. The thiamine pyrophosphokinase (TPK) activates thiamine into TDP and the numerous phosphatases perform the reverse two-step dephosphorylation of TDP to thiamine monophosphate (TMP) and then to free thiamine. Properties and a possible cooperation of those enzymes in higher plants have not been extensively studied. In this work, we characterize highly purified preparations of TPK and a TDP/TMP phosphatase isolated from 6-day Zea mays seedlings. TPK was the 29-kDa monomeric protein, with the optimal activity at pH 9.0, the K(m) values of 12.4microM and 4.7mM for thiamine and ATP, respectively, and the V(max) value of 360pmol TDPmin(-1)mg(-1) protein. The enzyme required magnesium ions, and the best phosphate donor was GTP. The purified phosphatase was the dimer of 24kDa subunits, showed the optimal activity at pH 5.0 and had a rather broad substrate specificity, although TDP, but not TMP, was one of the preferable substrates. The K(m) values for TDP and TMP were 36microM and 49microM, respectively, and the V(max) value for TDP was significantly higher than for TMP (164 versus 60nmolesmin(-1)mg(-1) protein). The total activities of TPK and TDP phosphatases were similarly decreased when the seedlings were grown under the illumination, suggesting a coordinated regulation of both enzymes to stabilize the pool of the essential coenzyme.

  7. Chemical form of technetium in corn (Zea mays) and the gastrointestinal absorption of plant-incorporated Tc by laboratory rats

    Energy Technology Data Exchange (ETDEWEB)

    Garten, C.T. Jr.; Myttenaere, C.; Vandecasteele, C.M.; Kirchmann, R.; Van Bruwaene, R.

    1984-01-01

    The food chain availability of technetium incorporated into plant tissue, its chemical form in corn leaves, and the potential for gastrointestinal absorption of plant-incorporated technetium was investigated. Technetium-95m was incorporated into corn leaves via root uptake. Chemical fractionation of the /sup 95m/Tc in leaves showed that 60% was extractable with boiling ethanol and weak mineral acids. The remainder was associated with cell walls and was extractable by harsh chemical treatment. Gel permeation chromatography of the cytosol, indicated that 50% of the /sup 95m/Tc co-chromatographed with anionic pertechnetate; however, it was impossible to distinguish if this pure pertechnetate or technetium complexed with organic molecules. Technetium-95m was administered to laboratory rats in a single dose as: (1) intravenous injection of pertechnetate, (2) pertechnetate mixed with standard laboratory food, and (3) a meal containing /sup 95m/Tc biologically incorporated into corn leaves. High concentrations of /sup 95m/Tc were found in the thyroids, hair, kidneys, and liver of rats. Technetium rapidly disappeared from the liver, kidneys, and other tissues, but remained in the thyroids and hair. Urinary excretion of technetium decreased, and fecal excretion increased when technetium was fed to rats as a /sup 95m/Tc incorporated into corn leaves. The percent of the administered dose absorbed into thyroid gland and the kidneys was less when technetium was biologically incorporated into corn leaves than when pertechnetate was mixed with food. Biological incorporation of technetium into plants appears to reduce its potential for food chain transfer by decreasing its availability for gastrointestinal absorption. 5 references, 4 figures, 3 tables.

  8. The response of maize (Zea mays L.) plant assisted with bacterial consortium and fertilizer under oily sludge.

    Science.gov (United States)

    Shahzad, Asim; Saddiqui, Samina; Bano, Asghari

    2016-01-01

    The objective of this study was to evaluate the role of PGPR consortium and fertilizer alone and in combination on the physiology of maize grown under oily sludge stress environment as well on the soil nutrient status. Consortium was prepared from Bacillus cereus (Acc KR232400), Bacillus altitudinis (Acc KF859970), Comamonas (Delftia) belonging to family Comamonadacea (Acc KF859971) and Stenotrophomonasmaltophilia (Acc KF859973). The experiment was conducted in pots with complete randomized design with four replicates and kept in field. Oily sludge was mixed in ml and Ammonium nitrate and Diammonium phosphate (DAP) were added at 70 ug/g and 7 ug/g at sowing. The plant was harvested at 21 d for estimation of protein, proline and antioxidant enzymes superoxide dismutase (SOD) and peroxidase (POD). To study the degradation, total petroleum hydrocarbon was extracted by soxhelt extraction and extract was analyzed by GC-FID at different period after incubation. Combined application of consortium and fertilizer enhanced the germination %, protein and, proline content by 90,130 and 99% higher than untreated maize plants. Bioavailability of macro and micro nutrient was also enhanced with consortium and fertilizer in oily sludge. The consortium and fertilizer in combined treatment decreased the superoxide dismutase (SOD), peroxidase dismutase (POD) of the maize leaves grown in oily sludge. Degradation of total petroleum hydrocarbon (TPHs) was 59% higher in combined application of consortium and fertilizer than untreated maize at 3 d. The bacterial consortium can enhanced the maize tolerance to oily sludge and enhanced degradation of total petroleum hydrocarbon (TPHs). The maize can be considered as tolerant plant species to remediate oily sludge contaminated soils.

  9. Characterization of Potential Plant Growth Promoting Rhizobacteria Isolated from Maize (Zea mays L. in Central and Northern Benin (West Africa

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    Nadège A. Agbodjato

    2015-01-01

    Full Text Available Our study aims to characterize Plant Growth Promoting Rhizobacteria (PGPR isolated from maize roots in five agroecological zones of central and northern Benin. Sixty samples were collected at the rate of four samples per village and three villages per agroecological zone. Rhizobacteria strains were isolated from these samples and biochemically characterized. These strains were analyzed for some of their PGPR traits like ammonia production and hydrogen cyanide following conventional methods. Microbiological investigation of these samples has shown that maize rhizospheres in central and northern Benin contain a high diversity of microorganisms. A total of nine species of maize Plant Growth Promoting Rhizobacteria were identified. Those PGPR include five Bacillus species (B. polymyxa, B. pantothenticus, B. anthracis, B. thuringiensis, and B. circulans, three Pseudomonas species (P. cichorii, P. putida, and P. syringae, and Serratia marcescens. The microbial diversity does not depend on the soil types. The microbial density, generally high, varies according to both soil types and agroecological zones. All Serratia strains (100% have produced ammonia, whereas 80% of Bacillus and 77.77% of Pseudomonas produced this metabolite. The hydrogen cyanide was produced by all isolates (100% independent of their genus. These results suggest the possibility to use these rhizobacteria as biological fertilizers to increase maize production.

  10. Determination of plant growth promoting potential of enterobacteria isolated from the rhizosphere of maize (Zea mays L.

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    Luis H. León Mendoza

    2014-12-01

    Full Text Available The yellow maize is the third most important crop in Peru and part of the chain maize-poultry-pig, significant impact on the national economic and social activity, however, in 2011, only 40% of the corn offered corresponded to the domestic industry. Looking for alternatives to reduce the use of chemical fertilizers, have performed investigations with plant growth promoting rhizobacteria. Bacteria were isolated from the rhizosphere of maize from districts Monsefú and Reque, Lambayeque. Dilution was made into sterile saline 0.87% NaCl w/v and plated on MacConkey agar, incubating at 30°C for 48 hours. 269 pure cultures of bacteria were obtained, the biochemical reaction was investigated in agar Triple sugar iron agar Iron Lysine, agar Citrate Simons, peptone broth, red broth methyl Voges-Proskauer and nitrate broth, was identified 66% as Enterobacteriaceae of genera Pantoea (49%, Klebsiella (17%, Kluyvera (16%, Serratia (11%, Citrobacter (4% and Hafnia (3%. The native enterobacteria were quantified to 31.67 ppm of fixed nitrogen as ammonia; 54.25 ppm indole acetic acid and 4,78 ppm solubilized phosphorus, activity proteolytic and chitinolytic and antagonistic activity of Fusarium verticillioides were also determined. 16% of native enterobacteria did not affect the emergence of hard yellow maize, 77% affected positively and 7% affected negatively. In turn, none bacteria affected survival. Was demonstrated the potential plant growth promoter of enterobacteria isolated from field crops in the region of Lambayeque.

  11. Effect of various soil salinity level on the antioxidant and physiological properties of corn plant (Zea mays

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    Ramin Ezzati

    2015-10-01

    Full Text Available To study the effect of various soil salinity levels on the antioxidant enzymes and physiological characteristics of corn as an indicator of salt stress resistance, present study was conducted in 2013 at Research lab of environmental, Faculty of Biological Sciences, University of Kharazmi, Iran. Furthermore, desert soils of Libya, India, Iraq and Karaj were used for testing the effect of soil salinity on the quantity of oxidant enzymes and various properties of maize plant. For providing favorable atmospheric conditions 33000 lux light and spray of perlite medium was used. Corn crop is highly sensitive to soil salinity so all the cultivation was carried out under conditions of soil EC lower than 20 ds/m and 8.5 pH. Results of the study revealed that the salt stress significantly affect the amount of antioxidant enzymes such as guaiacol peroxidase and malondialdehyde. Furthermore, it was reported that saline soil did not have any negative effect on the physiological characteristics and growth of corn plant growth.

  12. ZEA MAIZE: A MODERN CRAZE

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    Dhamija Isha

    2013-06-01

    Full Text Available Zea stands for ‘sustaining life’ and Mays stands for ‘life giver’. Zea mays is one of the oldest and most dynamic crop species, which has gained popularity in modern world too, due to its applications in diverse dishes. Corn is produced in every continent of the world with the exception of Antarctica. It is an annual monoecious sunny plant, surviving perfectly in nutrient rich, well-drained soil. Each and every part of the corn, from husk to corn silk is beneficial for the society. There are more than 3,500 different uses for corn products. Corn does much more than feed people and livestock. The plant contains alkaloids, flavonoids, saponins, maizenic acid, vitamins B1, K and minerals like potassium, phosphorous and zinc. Traditionally, Maize is used as an analgesic, anti-diarrheal, anti-prostatitic, anti-lithiasis, anti-tumor, anti-hypertensive, anti-diabetic, anti-hyperlipidemic, anti-inflammatory and anti-oxidant. In this review article, we have narrated miscellaneous uses of corn varieties and described the pharmacological activities, phytoconstituents, nutritional value and traditional uses of maize. The maize has assorted uses like culinary, medicinal and industrial. Corn dishes like corn-meal, corn-flakes, popcorn, “makki ki roti” and corn soup highlight its dominance all over the world. Therefore, maize has become a craze among modern youth.

  13. Utilisation des mutations induites pour l'étude de l'embryogenèse chez le haricot Phaseolus vulgaris L. et deux plantes modèles Arabidopsis thaliana (L. Heynh. et Zea mays L.

    Directory of Open Access Journals (Sweden)

    Silué, S.

    2011-01-01

    Full Text Available Use of induced mutations in embryogenesis study in bean Phaseolus vulgaris L. and two model plants, Arabidopsis thaliana (L. Heynh. and Zea mays L.. Breeding of common bean, Phaseolus vulgaris L., through interspecific hybridizations with the species Phaseolus coccineus L. and Phaseolus polyanthus Greenm. as female parents leads to the abortion of immature embryos. Identification of genes required for embryo development could partly explain the abortion of hybrid embryos; induced mutations could thus be an alternative to identify key genes involved in Phaseolus embryogenesis. This paper is a review which shows a few examples of the use of induced mutations in the identification of essential genes for embryogenesis in two model plants, Arabidopsis thaliana (L. Heyhn. for dicots and Zea mays L. for monocots. In these two species, embryo development mutants have been isolated using insertional mutagenesis and chemical mutagenesis with Ethyl Methane Sulfonate (EMS. Arabidopsis embryo mutants are affected in apical-basal axis polarity, radial pattern and in post-embryonic stages. Some Arabidopsis embryo mutants are defected in auxin signalisation. In maize, defective kernel (dek mutants are affected in the embryo and the endosperm, while in embryo specific (emb mutants, only the embryo is affected. In common bean, plants deficient in seed development were isolated using EMS mutagenesis. Embryos inside the seeds fail to growth at different stages of development and show abnormalities mainly in the suspensor and the cotyledons.

  14. Effects of different irrigation methods and plant densities on silage quality parameters of PR 31Y43 hybrid corn cultivar (Zea mays L. var. indentata [Sturtev.] L.H. Bailey

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    Muhammet Karasahin

    2014-03-01

    Full Text Available The yield and quality of corn silage is related to genotype as well as factors such as climate, soil conditions, altitude, planting time, plant density, irrigation, and harvesting time. This study was conducted to determine the effects of different irrigation methods (drip, subsoil drip, and subsoil capillary and different plant densities (102 040, 119 040, and 142 850 plant ha-1 on silage quality parameters of PR 31Y43 hybrid corn (Zea mays L. var. indentata [Sturtev.] L.H. Bailey in 2011 and 2012 under ecological conditions in Eskipazar-Karabuk, Turkey. Plant densities were significantly different on fresh ear ratio and plant crude protein (CP yield in both years under study. The highest fresh ear ratio values were obtained with 102 040 and 119 040 plant ha-1 densities and the highest plant CP yield with 142 850 plant ha-1. While the irrigation method x plant density interactions were significant for silage CP ratio in the first year, they were significant on fresh ear ratio in the second year. The highest fresh ear ratio values were obtained from subsoil capillary x 119 040 plant ha-1 and drip x 119 040 plant ha-1 interactions; the highest plant and silage CP ratio values were obtained from subsoil capillary x 142 850 plant ha-1 and subsoil drip x 102 040 plant ha-1 interactions. As a result of the research, high Flieg scores were obtained from each irrigation method and plant density. When plant CP yield is taken into consideration, the 142 850 plant ha-1 density is more important.

  15. Recurrent Selection and Participatory Plant Breeding for Improvement of Two Organic Open-Pollinated Sweet Corn (Zea mays L. Populations

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    Adrienne C. Shelton

    2015-04-01

    Full Text Available Organic growers face unique challenges when raising sweet corn, and benefit from varieties that maintain high eating quality, germinate consistently, deter insect pests, and resist diseases. Genotype by environment rank changes can occur in the performance of cultivars grown on conventional and organic farms, yet few varieties have been bred specifically for organic systems. The objective of this experiment was to evaluate the changes made to open-pollinated sweet corn populations using recurrent selection and a participatory plant breeding (PPB methodology. From 2008 to 2011, four cycles of two open-pollinated (OP sweet corn populations were selected on a certified organic farm in Minnesota using a modified ear-to-row recurrent selection scheme. Selections were made in collaboration with an organic farmer, with selection criteria based on traits identified by the farmer. In 2012 and 2013, the population cycles were evaluated in a randomized complete block design in two certified organic locations in Wisconsin, with multiple replications in each environment. Significant linear trends were found among cycles of selection for quantitative and qualitative traits, suggesting the changes were due to recurrent selection and PPB methodology for these populations. However, further improvement is necessary to satisfy the requirements for a useful cultivar for organic growers.

  16. Vene kunstnikud Eestis / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2005-01-01

    Näitus "Vene kunstnikud Eestis XX sajandi algupoolel" Eesti Ajaloomuuseumi Maarjamäe filiaalis 2005. a. lõpuni. Kuraator Nikolai Kormashov. Näitusekataloogi kujundas Andrei Kormashov, sissejuhatuse kirjutas Mai Levin, kunstnike biograafiad Sergei Issakov

  17. Vene kunstnikud Eestis / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2005-01-01

    Näitus "Vene kunstnikud Eestis XX sajandi algupoolel" Eesti Ajaloomuuseumi Maarjamäe filiaalis 2005. a. lõpuni. Kuraator Nikolai Kormashov. Näitusekataloogi kujundas Andrei Kormashov, sissejuhatuse kirjutas Mai Levin, kunstnike biograafiad Sergei Issakov

  18. Effects of humic acids (carbovit on phosphorus, bases and micronutrients of a molisol, with corn as an indicator plant (Zea mays L. Efectos de los ácidos húmicos (Carbovit sobre el fosforo, las bases y los micronutrientes de un molisol, utilizando como planta indicadora el maíz (Zea mays L

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    Guarin Sandra

    1993-12-01

    Full Text Available In order to establish the influence of humic substances (Carbovit on phosphorus, bases exchanges and microelements of a Molisol, greenhouse essays were peñormed at the College of Agriculture of the National Universityof Colombia located in Santafé de Bogotá, during the second semester of 1992. The experiment was taken into plastic vases using com (Zea mays L. as an indicator plant until sixty days after sowing. Resutts show that the humic acid molecule acts as a transport of solouble fertilizers appliedto the soil. Besides, elements like phosphorus,
    iron, magnesium and zinc showed increased levels of those elements in solution in to the soil. It was also found an equilibrium activity among bases relation ship, altributed to the humic acid molecule.
    Con el objeto de establecer la influencia de los ácidos húmicos (Carbovit sobre el fósforo, las bases de cambio y los micro elementos de un suelo calcáreo (Molisol, se realizó un ensayo en los invernaderos de la Facultad de Agronomla de la Universidad Nacional de Colombia, durante el segundo semestre de 1992. El experimento se llevo a cabo en materas
    plasticas utilizando como planta indicadora el maíz (Zea mays L. hasta los 60dlas después de siembra. Los resultados muestran que la molécula del ácido húmico actua como transportadora de los fertilizantes solubles aplicados al suelo. Además, elementos como el fósforo, hierro, magnesio y zinc se solubilizaron apreciablemente elevando los niveles de dichos elementos en la solución del suelo. También, se encontró una actividad equilibrante entre las relaciones de las bases, atribuida a la molecula del ácido húmico.

  19. Maize, tropical (Zea mays L.).

    Science.gov (United States)

    Assem, Shireen K

    2015-01-01

    Maize (Zea mays L.) is the third most important food crop globally after wheat and rice. In sub-Saharan Africa, tropical maize has traditionally been the main staple of the diet; 95 % of the maize grown is consumed directly as human food and as an important source of income for the resource-poor rural population. The biotechnological approach to engineer biotic and abiotic traits implies the availability of an efficient plant transformation method. The production of genetically transformed plants depends both on the ability to integrate foreign genes into target cells and the efficiency with which plants are regenerated. Maize transformation and regeneration through immature embryo culture is the most efficient system to regenerate normal transgenic plants. However, this system is highly genotype dependent. Genotypes adapted to tropic areas are difficult to regenerate. Therefore, transformation methods used with model genotypes adapted to temperate areas are not necessarily efficient with tropical lines. Agrobacterium-mediated transformation is the method of choice since it has been first achieved in 1996. In this report, we describe a transformation method used successfully with several tropical maize lines. All the steps of transformation and regeneration are described in details. This protocol can be used with a wide variety of tropical lines. However, some modifications may be needed with recalcitrant lines.

  20. Molecular analysis of CYP321A1, a novel cytochrome P450 involved in metabolism of plant allelochemicals (furanocoumarins) and insecticides (cypermethrin) in Helicoverpa zea.

    Science.gov (United States)

    Sasabe, Masataka; Wen, Zhimou; Berenbaum, May R; Schuler, Mary A

    2004-09-01

    Cytochrome P450 monooxygenases play a significant role in the detoxification of hostplant allelochemicals and synthetic insecticides in Lepidoptera. In the corn earworm Helicoverpa zea, a noctuid of considerable economic importance, metabolisms of xanthotoxin, a toxic furanocoumarin, and alpha-cypermethrin, an insecticide, are mediated by at least one P450 with a catalytic site capable of accepting both substrates. To further the characterization of P450s in this species, we have cloned three full-length cDNAs encoding two CYP4M subfamily members and a novel CYP321A subfamily member. RNA analyses have demonstrated that the CYP321A1 gene is highly induced (51-fold) in larval midguts in response to xanthotoxin but not cypermethrin. Both CYP4M genes are expressed at negligible levels that are not increased by xanthotoxin or cypermethrin. Baculovirus-mediated expression of the full-length CYP321A1 cDNA has demonstrated that the CYP321A1 protein metabolizes xanthotoxin and angelicin, like the CYP6B1 protein in the furanocoumarin specialist Papilio polyxenes, and alpha-cypermethrin, like the CYP6B8 protein previously characterized in H. zea. In contrast, the CYP4M7 protein does not metabolize xanthotoxin at any detectable level. We conclude that at least two xanthotoxin-inducible P450s from highly divergent subfamilies (CYP6B and CYP321A) contribute to the resistance of H. zea larvae to toxic furanocoumarins and insecticides. Genomic PCR analysis indicates that the CYP321A1 gene has evolved independently from the CYP6B genes known to be present in this insect.

  1. Letramento: uma aprendizagem mais significativa

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    Cristiane Carvalho Mendonça Blanco

    2012-06-01

    Full Text Available Esse artigo expõe a pesquisa realizada sobre Letramento: uma aprendizagem mais significativa teve como questão norteadora as muitas reflexões sobre o que pode ser feito para tornar o processo do contato inicial da criança com o letramento em um momento mais significativo e democrático, de modo que a criança se sinta sujeito de sua aprendizagem. Diante disso, foi observada uma turma de primeiro ano da Escola Municipal de Educação Básica Jardim Paraíso, no Município de Sinop – MT, e a professora regente desta turma, teve como abordagem teórica o estudo de Magda Soares. Por meio de uma entrevista e observações, foi possível conhecer quais os materiais didáticos que são utilizados em sala de aula e como os alunos interagem com este material. O caminho metodológico utilizado foi a pesquisa qualitativa, mais especificamente o Estudo de Caso. Constatou-se que a alfabetização só tem sentido em um contexto de letramento e por meio de atividades de letramento, este, por sua vez, só pode desenvolver-se por meio da aprendizagem do sistema de escrita.Palavras-chave: educação; ensino fundamental; letramento; professora e crianças; pesquisa descritiva; Magda Soares.

  2. Induction of glutathione S-Transferase in Helicoverpa zea fed cashew flour.

    Science.gov (United States)

    H. zea and other insects have evolved strategies to counteract the plant protective proteins and defensive compounds they may encounter during feeding. We sought to take advantage of this phenomenon by identifying proteins upregulated in H. zea in response to the inclusion of cashew nut flour in th...

  3. Effects of INH, DNP, 2, 4-D and CMU on the sugar content of the barley and maize leaves; Efecto de cuatro inhibidores metabolicos (INH, DNP, 2, 3-D y CMU) sobre el contenido en azucares de hohas de cebada (Hordeum vulgare L.) y Maiz (Zea mais L.)

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, J.; Sancho, P.

    1979-07-01

    1 ppm of the chemicals in nutritive solution was absorbed by barley and maize roots during 24 and 48 hours in dark or light conditioners in order to determine the best conditions. for the obtention of labelled sugars with high specific activity. Results show that the highest specific activity was obtained In maize plants treated with DNP for 24 hours in dark conditions. (Author) 51 refs.

  4. Caracterização e quantificação de Benzoxazolinona (BOA em extratos de plantas de milho (Zea mays L. = Characterization and quantification of Benzoxazolinone (BOA in maize plant extract (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Luis Wagner Rodrigues Alves

    2007-07-01

    Full Text Available Em função da interferência do milho em outras plantas, objetivou-se verificar a presença e a concentração de benzoxazolinona no milho por meio de extração aquosa obtida de material vegetal das cultivares AG-1051, C-333 e C-435. A massa fresca das amostras foi colocada em água destilada e deixada em repouso durante quatro horas. O extrato foi filtrado e particionado em solventes com diferentes polaridades. O extrato etéreo desidratado foi filtrado, concentrado em evaporador rotatório e levado à estufa. Este foi purificado por cromatografia de camada delgada. Recristalizou-se em hexano, e os cristais obtidos foram submetidos à análise em espectrometria no Infravermelho. As bandas presentes no produto padrão também foram caracterizadas nas amostras das cultivares de milho testadas. As amostras dos extratos foram qualificadas e quantificadas por espectrofotometria de ultravioleta. Pelos resultados, infere-se que a planta de milho possuiem seu metabolismo a benzoxazolinona, na seguinte ordem decrescente: AG-1051 29 mg g-1, C-333 24 mg g-1 e C-435 21 mg g-1 de BOA.Due to the interference of maize on other plants, the presence and concentration of benzoxazolinone in this particular plant (maize wasdetermined via the aqueous extract of three varieties of maize (AG-1051, C-333 and C-435. The fresh sample material was allowed to stand in distilled water for four hours. The extract was filtered and partitioned with solvents of varying polarities. The dried etherextract was filtered, concentrated on a rotary evaporator and dried in an oven. The residue was purified by thin layer chromatography and recrystallized from hexane. The crystals were analyzed by infrared spectroscopy. The bands present in the spectrum of the referencesubstance were also observed in the spectra of the samples obtained from the three varieties of maize studied. The extract samples were characterized and quantified by UV spectroscopy. The results indicated that the

  5. Induced cytomictic diversity in maize (Zea mays L.) inbred.

    Science.gov (United States)

    Rai, Prashant Kumar; Kumar, Girjesh; Tripathi, Avinash

    2010-01-01

    Mutation breeding has been used for improving oligogenic and polygenic characters, disease resistance and quantitative characters including yielding ability. The cytological stability of maize inbred lines is an important consideration in view of their extensive use in genetics and plant breeding research. Investigation in Zea mays L. confirms that the migration of chromosomes is a real event that cannot be misunderstood as an artifact produced by fixation or mechanical injuries. During present investigation, we found that out of six inbred lines of Zea mays L. viz. CM-135, CM-136, CM-137, CM-138, CM-142 and CM-213 at various treatment doses of gamma irradiations viz. 200, 400 and 600 Gy, some of the plants of inbred line CM- 138 at 200 Gy dose displayed characteristic cytoplasmic connections during all the stages of meiosis. Four plants from this treatment set were found to be engaged in a rare phenomenon reported as "Cytomixis". It elucidates that in inbred of Zea mays L., induced cytomixis through gamma rays treatment may be considered to be a possible source of production of aneuploid and polyploid gametes. This phenomenon may have several applications in Zea mays L. improvement in the sense of diversity and ever yield potential.

  6. Effects of planting pattern and density on growth indices, yield and yield component of corn (Zea mays in competition with redroot pigweed (Amaranthus retrofelexus(

    Directory of Open Access Journals (Sweden)

    alireza barkhi

    2009-06-01

    Full Text Available An experiment was conducted in 2002-2003 using split-split plot arrangement based on Rondomised Compelete Block Design with three replications at Feiz Abad Agricultural Research Station of Qazvin, in order to study of planting patterns and corn densitis effect in competition with redroot pigweed. Main plots inclouded two planting pattern of corn (P1: single row and P2: double row, sub plots inclouded two corn densities (D1:7 and D2:10 plant/m2 and sub sub plots inclouded 4 weed densities (C1:0, C2:2, C3:6, C4:12 plant/m2. Sampling conducted in 2-weekly intervals and growth indices evaluated. Results indicated that with increasing of weed density CGR, TDW, LAI, number of seeds in row, grain and ear yield decreased but plant height increased. Also LAI, CGR, TDW, number of weed seed and seed,s weight of weed increased. By increasing in corn density LAI, CGR, TDW, ear and grain yield increased, but length and diameter of ear and number of seeds in row decreased. Also LAI and CGR of weed increased, but TDW was decreased. In double row planting pattern just CGR, LAI, TDW of corn were higher significantly than single row planting pattern. But single row planting of weed caused higher LAI, NAR, RGR, CGR and TDW of weed in comparison with double row planting pattern. In 2-way interaction, double row planting pattern and zero densities and 2 weeds/m2 had highest grain yield respectively. There were no significant differences for 3-way interactions but double row planting pattern 10 plant density of corn/m2 zero weed/ m2 had highest grain yield.

  7. Effect of planting density on root lodging resistance and its relationship to nodal root growth characteristics in maize (Zea mays L.)

    DEFF Research Database (Denmark)

    Liu, Shengqun; Song, Fengbin; Liu, Fulai

    2012-01-01

    Increase of planting density has been widely used to increase grain yield in maize. However, it may lead to higher risk of root lodging hence causing significant yield loss of the crop. The objective of this study was to investigate the effect of planting density on maize nodal root growth...

  8. Growth response of maize plants (Zea mays L.) to wheat and lentil pre-cropping and to indigenous mycorrhizal in field soil

    Energy Technology Data Exchange (ETDEWEB)

    Almaca, A.; Ortas, I.

    2010-07-01

    The presence of indigenous mycorrhizal fungi may have significant effects on the growth and on the root morphology of plants, under arid and semi arid soil conditions. Lentil and wheat are the traditional crops grown in Southeastern Turkey. In this study soil samples from the Harran plain were collected from the 0-15 cm surface layer under wheat or lentil crop residues and used in a pot experiment carried out under greenhouse conditions with four levels of P fertilization: 0, 20, 40 and 80 mg kg{sup -}1 soil as Ca(H{sub 2}PO{sub 4}){sub 2}. Half of the soil batches were submitted to a heating treatment (80 degree centigrade, 2 h). The maize variety PX-9540 was grown in the pots for 57 days. At harvest, plant dry weight, root length, P and Zn concentrations in plant tissues were measured and the extent of root colonization by arbuscular mycorrhizal fungi (AMF) was determined. Results showed that maize plants grown in soils where lentil had been previously cultivated grew better than those grown after wheat cultivation. In both cases, P concentration in plant tissues increased with increased P fertilization. There were no significant differences in root AMF colonization between soils with different crop sequences, nor with soils submitted to high temperature. Previous crops had a significant influence on the growth of plants that could be related to differences in the indigenous mycorrhizas inoculum potential and efficacy that can promote P uptake and benefit plant growth. (Author) 29 refs.

  9. INVENTARISASI GULMA PADA TANAMAN JAGUNG (Zea mays L. DI LAHAN SAWAH KELURAHAN PADANG GALAK, DENPASAR TIMUR, KODYA DENPASAR, PROVINSI BALI

    Directory of Open Access Journals (Sweden)

    SURYANINGSIH -

    2013-05-01

    Full Text Available This study aims to determine the weed species that exist on Zea mays L. plant in paddyfields Padang Galak village, East Denpasar, Bali Province. This study is useful to provideinformation about the species of weeds found in maize (Zea mays L. in the fields of biology andagriculture, so weed control on Zea mays L. Plant can be implemented.Research was conducted from January 7 until March 11, 2011. In this study used themethod of cruising (exsploration sampling. To be more efficient and systematic results, alsoused a systematic method of lines.The results found 36 weed species belonging to 20 families. The distribution of theweed species, was found in Zea mays L. plant age of 4 weeks, which composed of 8 families 16Species. Weeds found in Zea mays L. plants aged of 6 weeks (the formation of fruit consistedof 10 familes and 23 species. While weeds found in Zea mays L. plants 8 weeks of age(ripening fruit were 14 families and 28 species. Weeds found in Zea mays L. plants aged 10weeks (before harvest comprised of 20 families and 36 species.

  10. Differential contribution of plant-beneficial functions from Pseudomonas kilonensis F113 to root system architecture alterations in Arabidopsis thaliana and Zea mays.

    Science.gov (United States)

    Vacheron, Jordan; Desbrosses, Guilhem; Renoud, Sébastien; Padilla-Aguilar, Rosa-Maria; Walker, Vincent; Muller, Daniel; Prigent-Combaret, Claire

    2017-10-03

    Fluorescent pseudomonads are playing key roles in plant-bacteria symbiotic interactions due to the multiple plant-beneficial functions (PBFs) they are harboring. The relative contributions of PBFs to plant-stimulatory effects of the well-known PGPR Pseudomonas kilonensis F113 (formerly P. fluorescens F113) were investigated using a genetic approach. To this end, several deletion mutants were constructed: simple mutants ΔphlD (impaired in the biosynthesis of 2,4-diacetylphloroglucinol [DAPG]), ΔacdS (deficient in 1-aminocyclopropane-1-carboxylate [ACC] deaminase activity), Δgcd (glucose dehydrogenase deficient, impaired in phosphate solubilization), and ΔnirS (nitrite reductase deficient) and a quadruple mutant (deficient in the 4 PBFs mentioned above). Every PBF activity was quantified in the wild-type strain and the five deletion mutants. This approach revealed few functional interactions between PBFs in vitro. In particular, biosynthesis of glucose dehydrogenase severely reduced the production of DAPG. Contrariwise, the DAPG production impacted positively, but to a lesser extent, phosphate solubilization. Inoculation of the F113 wild-type strain on Arabidopsis thaliana Col-0 and maize seedlings modified the root architecture of both plants. Mutant strain inoculations revealed that the relative contribution of each PBF differed according to the measured plant traits, and that F113 plant-stimulatory effects did not correspond to the sum of each PBF relative contribution. Indeed, two PBF genes (ΔacdS and ΔnirS) had a significant impact on root system architecture from both model plants, whether in in vitro and in vivo conditions. The current work underlined that few F113 PBFs seem to interact between each other in the free-living bacterial cells, whereas they control in concert Arabidopsis thaliana and maize growth and development.

  11. Synergistic Effects of Plant Growth Promoting Rhizobacteria and Chitosan on In Vitro Seeds Germination, Greenhouse Growth, and Nutrient Uptake of Maize (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Nadège A. Agbodjato

    2016-01-01

    Full Text Available This study aimed to assess the effects of three plant growth promoting rhizobacteria (PGPR and chitosan either singly or in combination on maize seeds germination and growth and nutrient uptake. Maize seeds were treated with chitosan and bacterial solution. The germination and growth tests were carried out in square Petri dishes and plastic pots. The combination chitosan-A. lipoferum-P. fluorescens has increased the seeds vigor index up to 36.44% compared to the control. In comparison to the control, P. putida has significantly improved root weight (44.84% and germinated seed weight (31.39% whereas chitosan-P. putida has increased the shoot weight (65.67%. For the growth test, the maximal heights (17.66% were obtained by plants treated with the combination A. lipoferum-P. fluorescens-P. putida. Chitosan-P. fluorescens induced the highest increases of leaves per plant (50.09%, aerial (84.66%, and underground biomass (108.77% production. The plants inoculated with A. lipoferum had the large leaf areas with an increase of 54.08%, while combinations P. fluorescens-P. putida and chitosan-A. lipoferum improved the aerial and underground dry matter of plants to 26.35% and 18.18%. The nitrogen content of the plants was increased by chitosan-A. lipoferum-P. fluorescens-P. putida with an increasing of 41.61%. The combination of chitosan and PGPR can be used as biological fertilizers to increase maize production.

  12. Plasmid-mediated Detoxification of Mycotoxin Zearalenone in Pseudomonas Sp. ZEA-1

    OpenAIRE

    2007-01-01

    The Pseudomonas sp. Strain ZEA-1 was isolated from rhizosphere of corn plant by an enrichment technique showed capability of utilizing zearalenone as the sole source of carbon. The bacterium rapidly utilized zearalenone beyond 200 µg/ml and showed prolific growth in a minimal medium containing 100 µg/ml zearalenone source. The course of ZEA degradation as well as the formation of its metabolites was observed by UV Spectrophotometer and thin layer chromatography analysis. Toxicity of biotransf...

  13. Increased Helicoverpa zea (Boddie) larval feeding on a RNAi construct CYP82D109 that blocks gossypol-related terpenoid synthesis in cotton plants

    Science.gov (United States)

    Glandled cotton plants, Gossypium hirsutum L., have long been known to be more resistant to insect pests compared to their glandless counterparts. This resistance has been mainly attributed to the presence of terpenoid aldehydes such as gossypol, hemigossypolone, and heliocides in the glands. We p...

  14. Effect of Plant Growth Promoting Rhizobacteria (PGPR on Phenological Traits, Grain Yield and Yield Components of Three Maize (Zea mays L. Cultivars

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    A Soleimani Fard

    2013-11-01

    Full Text Available To evaluate the effect of bio-fertilize on yield and its components in maize cultivars, an split plot experiment based on randomized complete bock design with three replications in was conducted in Payam-noor University of Ilam, Iran, in 2009-2010. Treatments were cultivar (SC604, SC704 and SC807 assigned to main plots and bio-fertilizer (non- inoculation, inoculation with Azetobacter, Azospirillum and dual inoculation ofAzotobacterand Azospirillum to subplots. The effect of cultivar on days to maturity, plant height, dry matter, ear length, stem diameter, number of grain per ear row, 1000-grain weight, grain yield, biological yield and protein content was significant cultivar. SC 704 had the highest dry matter (259.5 g.m-2, plant height (201.1 cm, number of grain per ear row (42.8 grain, grain yield (10850 kg.m-2, and biological yield (22040 kg.m-2. The effect of plant growth promoting rhizobacteria on all traits expect harvest index was significant. Dual inoculation ofAzotobacterand Azospirillum had the longest days to ear initiation (71.2 days, days to maturity (115.4 day, number of leaves above ear (5.6 ear, dry matter (240.4 g.m-2, ear length (24.3 cm, plant height (212.4 cm, seed number of rows per ear (14.5 row, number of grains per row (44.2 grain, grain yield (10190 kg.m-2, biological yield (21320 kg.m-2 and protein content (10.7%. Interaction effect of cultivar× plant growth promoting rhizobacteria on grain yield was significant. The highest and lowest grain yield was obtained from SC 704 and application of dual inoculation ofAzotobacterand Azospirillum (12320 kg.ha-1 and lowest from SC 604 when inoculation treatments were not used 7570 kg.ha-1 respectively.

  15. Effect of consolidate application of organic and chemical fertilizers on the physical and chemical traits of soil and qualitative index of corn (Zea mays L) plants

    OpenAIRE

    Esmaeil Namazi; Ebrahim Fatahi Nejad; Shahram Lak

    2015-01-01

    Present study was conducted to analysis the effect of Vermicompost and chemical nitrogen fertilizer on physical and chemical traits of soil's and qualitative indexes of corn plant. A factorial test with complete random block designs with 4 repetitions was conducted in the year of 2012. Three doses of chemical nitrogen fertilizers viz 50, 75 & 100 kg/hectare and two level of vermicompost viz 5 & 10 tons/hectare were used either individually or in combination with each others. Resul...

  16. Effect of plant growth promoting rhizobacteria containing ACC-deaminase on maize (Zea mays L.) growth under axenic conditions and on nodulation in mung bean (Vigna radiata L.).

    Science.gov (United States)

    Shaharoona, B; Arshad, M; Zahir, Z A

    2006-02-01

    This study was conducted to test the hypothesis that the bacterial strains possessing 1-aminocyclopropane-1-carboxylic acid (ACC)-deaminase activity may also promote growth of inoculated plants and could increase nodulation in legumes upon co-inoculation with rhizobia. Several rhizobacteria were isolated from maize rhizosphere through enrichment on ACC as a sole N source. Purified isolates were screened for growth promotion in maize under axenic conditions and for in vitro ACC-deaminase activity. A significant positive correlation was observed between in vitro ACC-deaminase activity of bacterial cells and root elongation. None of the isolates produced auxins. Bradyrhizobium japonicum produced less amount of auxins but did not carry ACC-deaminase activity. Results of pot experiment revealed that co-inoculation with Bradyrhizobium and plant growth promoting rhizobacteria (PGPR) isolates enhanced the nodulation in mung bean compared with inoculation with Bradyrhizobium alone. It is highly expected that inoculation with rhizobacteria containing ACC-deaminase hydrolysed endogenous ACC into ammonia and alpha-ketobutyrate instead of ethylene. Consequently, root and shoot growth as well as nodulation were promoted. The ACC-deaminase trait could be employed as an efficient tool to screen effective PGPR, which could be successfully used as biofertilizers to increase the growth of inoculated plants as well as nodulation in legumes.

  17. Metabolic profiling of two maize (Zea mays L.) inbred lines inoculated with the nitrogen fixing plant-interacting bacteria Herbaspirillum seropedicae and Azospirillum brasilense

    Science.gov (United States)

    Brusamarello-Santos, Liziane Cristina; Gilard, Françoise; Brulé, Lenaïg; Quilleré, Isabelle; Gourion, Benjamin; Ratet, Pascal; Maltempi de Souza, Emanuel; Lea, Peter J.; Hirel, Bertrand

    2017-01-01

    Maize roots can be colonized by free-living atmospheric nitrogen (N2)-fixing bacteria (diazotrophs). However, the agronomic potential of non-symbiotic N2-fixation in such an economically important species as maize, has still not been fully exploited. A preliminary approach to improve our understanding of the mechanisms controlling the establishment of such N2-fixing associations has been developed, using two maize inbred lines exhibiting different physiological characteristics. The bacterial-plant interaction has been characterized by means of a metabolomic approach. Two established model strains of Nif+ diazotrophic bacteria, Herbaspirillum seropedicae and Azospirillum brasilense and their Nif- couterparts defficient in nitrogenase activity, were used to evaluate the impact of the bacterial inoculation and of N2 fixation on the root and leaf metabolic profiles. The two N2-fixing bacteria have been used to inoculate two genetically distant maize lines (FV252 and FV2), already characterized for their contrasting physiological properties. Using a well-controlled gnotobiotic experimental system that allows inoculation of maize plants with the two diazotrophs in a N-free medium, we demonstrated that both maize lines were efficiently colonized by the two bacterial species. We also showed that in the early stages of plant development, both bacterial strains were able to reduce acetylene, suggesting that they contain functional nitrogenase activity and are able to efficiently fix atmospheric N2 (Fix+). The metabolomic approach allowed the identification of metabolites in the two maize lines that were representative of the N2 fixing plant-bacterial interaction, these included mannitol and to a lesser extend trehalose and isocitrate. Whilst other metabolites such as asparagine, although only exhibiting a small increase in maize roots following bacterial infection, were specific for the two Fix+ bacterial strains, in comparison to their Fix- counterparts. Moreover, a number

  18. Metabolic profiling of two maize (Zea mays L.) inbred lines inoculated with the nitrogen fixing plant-interacting bacteria Herbaspirillum seropedicae and Azospirillum brasilense.

    Science.gov (United States)

    Brusamarello-Santos, Liziane Cristina; Gilard, Françoise; Brulé, Lenaïg; Quilleré, Isabelle; Gourion, Benjamin; Ratet, Pascal; Maltempi de Souza, Emanuel; Lea, Peter J; Hirel, Bertrand

    2017-01-01

    Maize roots can be colonized by free-living atmospheric nitrogen (N2)-fixing bacteria (diazotrophs). However, the agronomic potential of non-symbiotic N2-fixation in such an economically important species as maize, has still not been fully exploited. A preliminary approach to improve our understanding of the mechanisms controlling the establishment of such N2-fixing associations has been developed, using two maize inbred lines exhibiting different physiological characteristics. The bacterial-plant interaction has been characterized by means of a metabolomic approach. Two established model strains of Nif+ diazotrophic bacteria, Herbaspirillum seropedicae and Azospirillum brasilense and their Nif- couterparts defficient in nitrogenase activity, were used to evaluate the impact of the bacterial inoculation and of N2 fixation on the root and leaf metabolic profiles. The two N2-fixing bacteria have been used to inoculate two genetically distant maize lines (FV252 and FV2), already characterized for their contrasting physiological properties. Using a well-controlled gnotobiotic experimental system that allows inoculation of maize plants with the two diazotrophs in a N-free medium, we demonstrated that both maize lines were efficiently colonized by the two bacterial species. We also showed that in the early stages of plant development, both bacterial strains were able to reduce acetylene, suggesting that they contain functional nitrogenase activity and are able to efficiently fix atmospheric N2 (Fix+). The metabolomic approach allowed the identification of metabolites in the two maize lines that were representative of the N2 fixing plant-bacterial interaction, these included mannitol and to a lesser extend trehalose and isocitrate. Whilst other metabolites such as asparagine, although only exhibiting a small increase in maize roots following bacterial infection, were specific for the two Fix+ bacterial strains, in comparison to their Fix- counterparts. Moreover, a number

  19. EFFECT OF DIFFERENT MULCHES ON THE CONTROL OF UNWISHED PLANTS IN MAIZE CROP (Zea mays EFEITO DE DIVERSAS ESPÉCIES DE COBERTURA MORTA SOBRE O CONTROLE DE PLANTAS DANINHAS DA CULTURA DO MILHO

    Directory of Open Access Journals (Sweden)

    Rogério de Araújo Almeida

    2007-09-01

    Full Text Available

    Researches of many South American countries point the zero tillage system of crop production for little farmers as a responsible factor for best soil and water conservation, less costs of production and best profits to improve the rural way of life. The treatments usually include the application of herbicides. To find agricultural systems that allow zero tillage without herbicide or with reduced usage has been considered a challenge by the researchers. This experiment was carried out in order to evaluate the effects of different mulches on the control of unwished plants in maize crop (Zea mays. Plants such as sunhemp (Crotalaria juncea, millet (Pennisetum americanum and sunflower (Helianthus annus L. cv. Stanzuela and V 2000 were grown in 100 m² areas. The sowing was made at the second April fortnight and, after sixty days, the zero tillage system with maize was established by using a manual planting machine. Just after, the plants grown in the plots were manually cut and used as mulch. The soil fertility was corrected according to the laboratorial analyses and the plant population adopted was around 60,000 plants per hectare. No weed control was made. At the maize flowering, the seed weeds grown in the plots were collected by using two samples of 1 m² plot (two replications. The plant material was dried till constant weight. Statistical analyses obtained from the data indicated the millet mulch as the best treatment to the weed control.

    Isolation of plant-growth-promoting rhizobacteria from rhizospheric soil of halophytes and their impact on maize (Zea mays L.) under induced soil salinity.

    Science.gov (United States)

    Ullah, Sami; Bano, Asghari

    2015-04-01

    The present investigation was aimed to scrutinize the salt tolerance potential of plant-growth-promoting rhizobacteria (PGPR) isolated from rhizospheric soil of selected halophytes (Atriplex leucoclada, Haloxylon salicornicum, Lespedeza bicolor, Suaeda fruticosa, and Salicornica virginica) collected from high-saline fields (electrical conductivity 4.3-5.5) of District Mardan, Pakistan. Five PGPR strains were identified using 16S rRNA amplification and sequence analysis. Bacillus sp., isolated from rhizospheric soil of Atriplex leucoclada, and Arthrobacter pascens, isolated from rhizospheric soil of Suaeda fruticosa, are active phosphate solubilizers and bacteriocin and siderophore producers; hence, their inoculation and co-inoculation on maize ('Rakaposhi') under induced salinity stress enhanced shoot and root length and shoot and root fresh and dry mass. The accumulation of osmolytes, including sugar and proline, and the elevation of antioxidant enzymes activity, including superoxide dismutase, peroxidase, catalase, and ascorbate peroxidase, were enhanced in the maize variety when inoculated and co-inoculated with Bacillus sp. and Arthrobacter pascens. The PGPR (Bacillus sp. and A. pascens) isolated from the rhizosphere of the mentioned halophytes species showed reliability in growth promotion of maize crop in all the physiological parameters; hence, they can be used as bio-inoculants for the plants growing under salt stress.

  1. Structure and expression of the maize (Zea mays L. SUN-domain protein gene family: evidence for the existence of two divergent classes of SUN proteins in plants

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    Simmons Carl R

    2010-12-01

    Full Text Available Abstract Background The nuclear envelope that separates the contents of the nucleus from the cytoplasm provides a surface for chromatin attachment and organization of the cortical nucleoplasm. Proteins associated with it have been well characterized in many eukaryotes but not in plants. SUN (Sad1p/Unc-84 domain proteins reside in the inner nuclear membrane and function with other proteins to form a physical link between the nucleoskeleton and the cytoskeleton. These bridges transfer forces across the nuclear envelope and are increasingly recognized to play roles in nuclear positioning, nuclear migration, cell cycle-dependent breakdown and reformation of the nuclear envelope, telomere-led nuclear reorganization during meiosis, and karyogamy. Results We found and characterized a family of maize SUN-domain proteins, starting with a screen of maize genomic sequence data. We characterized five different maize ZmSUN genes (ZmSUN1-5, which fell into two classes (probably of ancient origin, as they are also found in other monocots, eudicots, and even mosses. The first (ZmSUN1, 2, here designated canonical C-terminal SUN-domain (CCSD, includes structural homologs of the animal and fungal SUN-domain protein genes. The second (ZmSUN3, 4, 5, here designated plant-prevalent mid-SUN 3 transmembrane (PM3, includes a novel but conserved structural variant SUN-domain protein gene class. Mircroarray-based expression analyses revealed an intriguing pollen-preferred expression for ZmSUN5 mRNA but low-level expression (50-200 parts per ten million in multiple tissues for all the others. Cloning and characterization of a full-length cDNA for a PM3-type maize gene, ZmSUN4, is described. Peptide antibodies to ZmSUN3, 4 were used in western-blot and cell-staining assays to show that they are expressed and show concentrated staining at the nuclear periphery. Conclusions The maize genome encodes and expresses at least five different SUN-domain proteins, of which the PM3

  2. Interfacing carbon nanotubes (CNT) with plants: enhancement of growth, water and ionic nutrient uptake in maize ( Zea mays) and implications for nanoagriculture

    Science.gov (United States)

    Tiwari, D. K.; Dasgupta-Schubert, N.; Villaseñor Cendejas, L. M.; Villegas, J.; Carreto Montoya, L.; Borjas García, S. E.

    2014-06-01

    The application of nano-biotechnology to crop-science/agriculture (`nanoagriculture') is a recent development. While carbon nanotubes (CNTs) have been shown to dramatically improve germination of some comestible plants, deficiencies in consistency of behavior and reproducibility arise, partially from the variability of the CNTs used. In this work, factory-synthesized multi-walled-CNTs (MWCNTs) of quality-controlled specifications were seen to enhance the germinative growth of maize seedlings at low concentrations but depress it at higher concentrations. Growth enhancement principally arose through improved water delivery by the MWCNT. Polarized EDXRF spectrometry showed that MWCNTs affect mineral nutrient supply to the seedling through the action of the mutually opposing forces of inflow with water and retention in the medium by the ion-CNT transient-dipole interaction. The effect varied with ion type and MWCNT concentration. The differences of the Fe tissue concentrations when relatively high equimolar Fe2+ or Fe3+ was introduced, implied that the ion-CNT interaction might induce redox changes to the ion. The tissue Ca2+ concentration manifested as the antipode of the Fe2+ concentration indicating a possible cationic exchange in the cell wall matrix. SEM images showed that MWCNTs perforated the black-layer seed-coat that could explain the enhanced water delivery. The absence of perforations with the introduction of FeCl2/FeCl3 reinforces the idea of the modification of MWCNT functionality by the ion-CNT interaction. Overall, in normal media, low dose MWCNTs were seen to be beneficial, improving water absorption, plant biomass and the concentrations of the essential Ca, Fe nutrients, opening a potential for possible future commercial agricultural applications.

  3. The earliest archaeological maize (Zea mays L.) from highland Mexico: new accelerator mass spectrometry dates and their implications.

    Science.gov (United States)

    Piperno, D R; Flannery, K V

    2001-02-13

    Accelerator mass spectrometry age determinations of maize cobs (Zea mays L.) from Guilá Naquitz Cave in Oaxaca, Mexico, produced dates of 5,400 carbon-14 years before the present (about 6,250 calendar years ago), making those cobs the oldest in the Americas. Macrofossils and phytoliths characteristic of wild and domesticated Zea fruits are absent from older strata from the site, although Zea pollen has previously been identified from those levels. These results, together with the modern geographical distribution of wild Zea mays, suggest that the cultural practices that led to Zea domestication probably occurred elsewhere in Mexico. Guilá Naquitz Cave has now yielded the earliest macrofossil evidence for the domestication of two major American crop plants, squash (Cucurbita pepo) and maize.

  4. Stem characteristics of two forage maize (Zea mays L.) cultivars varying in whole plant digestibility. IV. Changes during the growing season in anatomy and chemical composition in relation to fermentation characteristics of a lower internode

    NARCIS (Netherlands)

    Boon, E.J.M.C.; Struik, P.C.; Engels, F.M.; Cone, J.W.

    2012-01-01

    Improving digestibility of forage maize (Zea mays L.) through breeding is important to optimize the efficiency of ruminant's rations. It can partly be achieved by improving the digestibility of stem tissue, a genetically complex and diverse trait changing drastically during the growing season. We

  5. Stem characteristics of two forage maize (Zea mays L.) cultivars varying in whole plant digestibility. II. Relation between in vitro rumen fermentation characteristics and anatomical and chemical features within a single internode

    NARCIS (Netherlands)

    Boon, E.J.M.C.; Engels, F.M.; Struik, P.C.; Cone, J.W.

    2005-01-01

    Internode 7 of the stem of two forage maize (Zea mays L.) cultivars was studied anatomically and chemically at anthesis and subjected to fermentation tests in rumen fluid, using an automated gas production system. For anatomical studies internode 7 was sectioned at the top, middle and base. For chem

  6. Stem characteristics of two forage maize (Zea mays L.) cultivars varying in whole plant digestibility. IV. Changes during the growing season in anatomy and chemical composition in relation to fermentation characteristics of a lower internode

    NARCIS (Netherlands)

    Boon, E.J.M.C.; Struik, P.C.; Engels, F.M.; Cone, J.W.

    2012-01-01

    Improving digestibility of forage maize (Zea mays L.) through breeding is important to optimize the efficiency of ruminant's rations. It can partly be achieved by improving the digestibility of stem tissue, a genetically complex and diverse trait changing drastically during the growing season. We tr

  7. Effect of consolidate application of organic and chemical fertilizers on the physical and chemical traits of soil and qualitative index of corn (Zea mays L plants

    Directory of Open Access Journals (Sweden)

    Esmaeil Namazi

    2015-06-01

    Full Text Available Present study was conducted to analysis the effect of Vermicompost and chemical nitrogen fertilizer on physical and chemical traits of soil's and qualitative indexes of corn plant. A factorial test with complete random block designs with 4 repetitions was conducted in the year of 2012. Three doses of chemical nitrogen fertilizers viz 50, 75 & 100 kg/hectare and two level of vermicompost viz 5 & 10 tons/hectare were used either individually or in combination with each others. Results of the study revealed that the use of Vermicompost and chemical nitrogen fertilizer caused a significant increase in the percentage of seed oil contents. At individual application of chemical nitrogen fertilizer highest increment in seed oil content was reported at 100 kg/hectare application, while in combination it was reported higher in the combination of 75 kg/hectare chemical Nitrogen fertilizer and 10ton/hectare vermicompost. The least effective treatment of was the combination of 100 kg/hectare chemical nitrogen fertilizer and 10 tons/hectare vermicompost combination. The most bulk gravity and real gravity is due to the treatment of Nitrogen chemical fertilizer at 50kg/hectare of soil test and without the use of vermicompost and the least bulk and real gravity of soil belong to the treatment of Nitrogen chemical fertilizer at the amount of 100kg/hectare of soil test and use of vermicompost at the amount of 10 tons in hectare.

  8. Feeding non-preference of the corn leaf aphid Rhopalosiphum maidis (Fitch, 1856 (Hemiptera: Aphididae to corn plants (Zea mays L. treated with silicon Não-preferência do pulgão-da-folha Rhopalosiphum maidis (Fitch, 1856 (Hemiptera: Aphididae para plantas de milho (Zea mays L. tratadas com silício

    Directory of Open Access Journals (Sweden)

    Jair Campos Moraes

    2005-08-01

    Full Text Available A tactic for control to corn leaf Rhopalosiphum maidis (Fitch, 1856 would be the use of resistant materials, but, for not being a key pest of the crop, there are not yet corn genotypes availables with those characteristics. So, it was aimed in this work to evaluate the effect of silicon on the aphid's development on corn plants. Preference tests with leaves detached from the plants and on corn plants were accomplished. Its was found that the treatments where silicon was applied to the soil plus a foliar sprayed fertilization or through two foliar applications were the ones which contained a lower number of aphids, increasing the resistance of leaves and making the feeding of those insects difficult. In general, the results showed that silicon affected the leaf aphid's preference.Uma tática para o controle do pulgão-do-milho Rhopalosiphum maids (Fitch, 1856 seria a utilização de materiais resistentes, porém, por não se tratar de uma praga-chave da cultura, não há, ainda, disponibilidade de genótipos de milho com essas características. Assim com o presente trabalho objetivou-se avaliar o efeito do silício na preferência do pulgão-da-folha em plantas de milho. Os tratamentos consistiram na aplicação de silício via solo e/ou foliar e testemunha. Foram realizados testes de não-preferência com folhas destacadas e diretamente em plantas de milho. Verificou-se que os tratamentos nos quais o silício foi aplicado via solo mais uma adubação foliar, ou mediante duas aplicações foliares, foram os que apresentaram menor número de pulgões, aumentando a resistência das folhas e dificultando a alimentação desses insetos. De modo geral, o silício afetou a preferência do pulgão-da-folha.

  9. Biology, Ecology, and Evolving Management of Helicoverpa zea (Lepidoptera: Noctuidae) in Sweet Corn in the United States.

    Science.gov (United States)

    Olmstead, Daniel L; Nault, Brian A; Shelton, Anthony M

    2016-08-01

    The corn earworm, Helicoverpa zea (Boddie), is a polyphagous pest found throughout the United States, where it attacks many field and vegetable crops. Although H. zea has long been a traditional pest of sweet corn, its importance to this crop has increased dramatically over the past two decades. In this review, we summarize information critical for current and future management of H. zea in sweet corn production in the United States. First, we discuss the pest status of H. zea and its life history, including migration, infestation and larval development, diapause, overwintering, and abiotic factors that affect its biology. Next we describe monitoring methods, crop protection decision-making processes, chemical control options, and the use of genetic technologies for control of H. zea Alternative H. zea management options including biological control, cultural controls, host plant resistance, and pheromone disruption are also reviewed. The role of climate change and its effects on H. zea and its ecology are discussed, as well as the recent invasion of its relative, Helicoverpa armigera (Hübner), which is a major pest of corn in other parts of the world. To conclude, we suggest future research opportunities for H. zea and H. armigera management in sweet corn.

  10. Assessment of the Phytotoxicity of Metal Oxide Nanoparticles on Two Crop Plants, Maize (Zea mays L.) and Rice (Oryza sativa L.).

    Science.gov (United States)

    Yang, Zhongzhou; Chen, Jing; Dou, Runzhi; Gao, Xiang; Mao, Chuanbin; Wang, Li

    2015-11-30

    In this study, the phytotoxicity of seven metal oxide nanoparticles(NPs)-titanium dioxide (nTiO₂), silicon dioxide (nSiO₂), cerium dioxide (nCeO₂), magnetite (nFe₃O₄), aluminum oxide (nAl₂O₃), zinc oxide (nZnO) and copper oxide (nCuO)-was assessed on two agriculturally significant crop plants (maize and rice). The results showed that seed germination was not affected by any of the seven metal oxide NPs. However, at the concentration of 2000 mg·L(-1), the root elongation was significantly inhibited by nCuO (95.73% for maize and 97.28% for rice), nZnO (50.45% for maize and 66.75% for rice). On the contrary, minor phytotoxicity of nAl₂O₃ was only observed in maize, and no obvious toxic effects were found in the other four metal oxide NPs. By further study we found that the phytotoxic effects of nZnO, nAl₂O₃ and nCuO (25 to 2000 mg·L(-)¹) were concentration dependent, and were not caused by the corresponding Cu(2+), Zn(2+) and Al(3+) ions (0.11 mg·L(-)¹, 1.27 mg·L(-)¹ and 0.74 mg·L(-)¹, respectively). Furthermore, ZnO NPs (<50 nm) showed greater toxicity than ZnO microparticles(MPs)(<5 μm) to root elongation of both maize and rice. Overall, this study provided valuable information for the application of engineered NPs in agriculture and the assessment of the potential environmental risks.

  11. Assessment of the Phytotoxicity of Metal Oxide Nanoparticles on Two Crop Plants, Maize (Zea mays L. and Rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Zhongzhou Yang

    2015-11-01

    Full Text Available In this study, the phytotoxicity of seven metal oxide nanoparticles(NPs—titanium dioxide (nTiO2, silicon dioxide (nSiO2, cerium dioxide (nCeO2, magnetite (nFe3O4, aluminum oxide (nAl2O3, zinc oxide (nZnO and copper oxide (nCuO—was assessed on two agriculturally significant crop plants (maize and rice. The results showed that seed germination was not affected by any of the seven metal oxide NPs. However, at the concentration of 2000 mg·L−1, the root elongation was significantly inhibited by nCuO (95.73% for maize and 97.28% for rice, nZnO (50.45% for maize and 66.75% for rice. On the contrary, minor phytotoxicity of nAl2O3 was only observed in maize, and no obvious toxic effects were found in the other four metal oxide NPs. By further study we found that the phytotoxic effects of nZnO, nAl2O3 and nCuO (25 to 2000 mg·L−1 were concentration dependent, and were not caused by the corresponding Cu2+, Zn2+ and Al3+ ions (0.11 mg·L−1, 1.27 mg·L−1 and 0.74 mg·L−1, respectively. Furthermore, ZnO NPs (<50 nm showed greater toxicity than ZnO microparticles(MPs(<5 μm to root elongation of both maize and rice. Overall, this study provided valuable information for the application of engineered NPs in agriculture and the assessment of the potential environmental risks.

  12. Growth and Production of Some Variety Corn (Zea mays L.). Planted under the Canopy of Palm Oil 12 Years Old in Swamp Land

    Science.gov (United States)

    Syafrullah; Marlina, N.; Rahim, S. E.; Aminah, R. I. S.; Midranisiah; Rosmiah; Sakalena, F.

    2017-06-01

    This research was conducted in wetlands Semambu Village, District of North Indralaya, Ogan Ilir, South Sumatra Province, Indonesia, which lasted from July 2015 to February 2016. The observation of a microclimate indicate that the average intensity of light outside the auspices of the plot 1968.9 m2s mol1, under waranet 1502.40 mol1 m2s, below paranet 721.99 mol1 m2s-1 and under waranet 439.25 μmol m2s-1 - equivalent to the light interception 1 or 100%, 76%, 37% and 22%. Results of soil chemical analysis that the soil has a low fertility study (H2O pH of 3.32, organic C 4.47%, total N 0.35%, Bray P 13.30 ppm, K-ea 0.26 me / 100g, CEC 19.6 rne / 100g and Al-ea 3.28 me / 100g). Tests on 22 genotypes of maize grown with light interception 100%, 76%. 37% and 22%, by calculating tolerance index based on the weight of dry seed cob-1 was found four genotypes of maize tend to be tolerant to low-intensity light that were genotype B 41, Pioneer 27, Sukmaraga and Sugihan. The test results of corn planted in beds shade with light interception 100%, 76%, 37% and 22% for groups of maize tolerant and sensitive, followed by application of urea 0 kg ha1, 100 kg ha-1 200 kg ha-1, 300 kg ha-1 and 400 kg ha-1 indicate that maize and 41 and Pioneer 27 by Urea 300 kg ha-1 gives better results than other varieties at different intensities of light oil palm age of 12 years with applications Urea fertilizer 300 kg ha-1, indicating that the B 41 and Pioneer 27 tends to give better results compared with other varieties. The application of a polyculture system palm-maize can produce 1000 kg of dry grain of corn in a 1 ha of oil palm cultivation.

  13. Mai Murdmaa neljas puutepunkt antiiktragöödiaga / Mai Murdmaa ; intervjueerinud Tiina Mattisen

    Index Scriptorium Estoniae

    Murdmaa, Mai, 1938-

    2010-01-01

    5. veebruaril Kumus auditooriumis esietenduvast Mai Murdmaa tantsulavastusest "Phaidra", mis on loodud Euripidese teose "Hippolytose" põhjal, osades Kaie Kõrb, Anatoli Arhangelski ja Aleksandr Prigorovski

  14. Effects of cotton condensed tannin, maysin (Corn) and pinitol (soybeans) onHeliothis zea growth and development.

    Science.gov (United States)

    Reese, J C; Chan, B G; Waiss, A C

    1982-12-01

    Maysin, a flavone glycoside from corn silks, inhibits ingestion, and thus growth, ofHeliothis zea (Boddie) larvae. Pinitol from soybeans inhibitedH. zea growth by the same mechanism. Despite the widely held assumption that tannins inhibit growth by inhibiting assimilation, cotton condensed tannin inhibitedH. zea growth by reducing ingestion; no evidence was found for a reduction in assimilation. Neonate larvae are shown to be much more sensitive to allelochemics than larvae that have fed on control diet before being transferred to diet containing plant allelochemics.

  15. Effect of rooting depth, plant density and planting date on maize (Zea Mays L.) yield and water use efficiency in semi-arid Zimbabwe: Modelling with AquaCrop

    NARCIS (Netherlands)

    Nyakudya, I.W.; Stroosnijder, L.

    2014-01-01

    Under low and poorly distributed rainfall higher food production can be achieved by increasing crop water use efficiency (WUE) through optimum soil fertility management and selection of deep-rooting cultivars, appropriate plant density and planting dates. We explored AquaCrop's applicability in sele

  16. Effect of rooting depth, plant density and planting date on maize (Zea Mays L.) yield and water use efficiency in semi-arid Zimbabwe: Modelling with AquaCrop

    NARCIS (Netherlands)

    Nyakudya, I.W.; Stroosnijder, L.

    2014-01-01

    Under low and poorly distributed rainfall higher food production can be achieved by increasing crop water use efficiency (WUE) through optimum soil fertility management and selection of deep-rooting cultivars, appropriate plant density and planting dates. We explored AquaCrop's applicability in

  17. "Zea"-Because It's There

    Science.gov (United States)

    Chamberlain, Eric

    1983-03-01

    The Subject is a long standing symbiotic relationship between Zea and the movies. As usual the impossible was required - to attain cinema release quality films with dramatic interpretation - at the same time using Hy-speed macro photographic techniques. The subject was not to be recognizable until the end of the film - some four minutes long. Zea is explosive, it reacts to heat and is extremely difficult to predict when it will explode, which left little time for the focus, stop down and shooting. Using a Hy-cam at 5,000 pictures per second - a 400 ft. roll of 7247 raw stock, left but a brief three seconds for synchronization. To add to the confusion, two co-directors, a cameraman, plus equipment, were jammed into a 2 x 2m space. To achieve reasonable resolution for theatrical showing, 400,000 foot/candles of light were needed. This was achieved. The film was edited and music from Vaughan Williams' "Fantasia" recorded at St. Martins-in-the-Fields, London was added. The result was sent to the Cannes Film Festival, where it was given the Jury Award.

  18. Quais os suplementos alimentares mais utilizados?

    OpenAIRE

    Alex Bisotto Ferreira; Valderi Abreu de Lima; William Cordeiro de Souza; Luis Paulo Gomes Mascarenhas; Neiva Leite

    2016-01-01

    O consumo de suplementos alimentares tem sido muito utilizado e difundido por praticantes de atividade física, em especial a musculação por pessoas com objetivos de melhora em desempenho, redução de gordura corporal, aumento de massa muscular entre outros. Esta pesquisa tem como objetivo revisar sobre quais os suplementos alimentares são utilizados na atualidade, e destacar o mais utilizado. A fonte dos dados é uma pesquisa bibliográfica realizada em média dos últimos 15 anos, foram examinado...

  19. Identification and characterization of digestive serine proteases from inhibitor-resistant Helicoverpa zea larval midgut

    NARCIS (Netherlands)

    Volpicella, M.; Cordewener, J.H.G.; Jongsma, M.A.; Gallerani, R.; Ceci, L.R.; Beekwilder, M.J.

    2006-01-01

    Protease inhibitors mediate a natural form of plant defence against insects, by interfering with the digestive system of the insect. In this paper, affinity chromatography was used to isolate trypsins and chymotrypsins from Helicoverpa zea larvae, which had been raised on inhibitor-containing diet.

  20. Elevated carbon dioxide reduces emission of herbivore induced volatiles in Zea mays

    Science.gov (United States)

    Terpene volatiles produced by sweet corn (Zea mays) upon infestation with pests such as beet armyworm (Spodoptera exigua) function as part of an indirect defense mechanism by attracting parasitoid wasps; yet little is known about the impact of atmospheric changes on this form of plant defense. To in...

  1. Differential distribution of cadmium in lettuce (Lactuca sativa L.) and maize (Zea mays L.).

    NARCIS (Netherlands)

    Florijn, P.J.

    1993-01-01

    Large genotypic variation in shoot Cd concentrations has been reported in literature for several plant species including lettuce ( Lactuca sativa L.) and maize ( Zea mays L.). The objective of this thesis was to elucidate the physiological andlor morphological basis of this differential behaviour us

  2. Effects of salt stress on germination of some maize (Zea mays L ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-05

    Oct 5, 2009 ... This study was conducted to investigate the effects of salt stress on germination of six maize (Zea mays L.) ... Salinity is a major environmental constraint to crop pro- ... Maize, which belongs to the plants with C4 metabolism,.

  3. Cytodifferentiation during callus initiation and somatic embryogenesis in Zea mays L.

    NARCIS (Netherlands)

    Fransz, P.F.

    1988-01-01

    This thesis deals with cytomorphogenic aspects during various phases of regeneration in tissue cultures of Zeamays L. Regeneration through tissue culture has been shown in an increasing number of plant species and is applied on large scale in agriculture and horticulture. Nevertheless,

  4. Quais os suplementos alimentares mais utilizados?

    Directory of Open Access Journals (Sweden)

    Alex Bisotto Ferreira

    2016-07-01

    Full Text Available O consumo de suplementos alimentares tem sido muito utilizado e difundido por praticantes de atividade física, em especial a musculação por pessoas com objetivos de melhora em desempenho, redução de gordura corporal, aumento de massa muscular entre outros. Esta pesquisa tem como objetivo revisar sobre quais os suplementos alimentares são utilizados na atualidade, e destacar o mais utilizado. A fonte dos dados é uma pesquisa bibliográfica realizada em média dos últimos 15 anos, foram examinados 232 estudos, sendo selecionados 48. Os suplementos alimentares discutidos nesse artigo foram: Carboidratos, vitaminas e minerais, l-carnitina, creatina, proteínas e aminoácidos. O principal motivo para a utilização de suplementos foi o aumento de massa muscular, predominantemente indicado por professores, instrutores e treinadores, apesar da grande variedade, os suplementos mais utilizados são as proteínas e aminoácidos, e, na maioria dos casos com o intuito de aumentar a massa muscular e melhorar sua recuperação.

  5. RNA-seq Analysis of Cold and Drought Responsive Transcriptomes of Zea mays ssp. mexicana L.

    Science.gov (United States)

    Lu, Xiang; Zhou, Xuan; Cao, Yu; Zhou, Meixue; McNeil, David; Liang, Shan; Yang, Chengwei

    2017-01-01

    The annual Zea mays ssp. mexicana L. is a member of teosinte, a wild relative of the Zea mays spp. mays L. This subspecies has strong growth and regeneration ability, high tiller numbers, high protein and lysine content as well as resistance to many fungal diseases, and it can be effectively used in maize improvement. In this study, we reported a Zea mays ssp. mexicana L. transcriptome by merging data from untreated control (CK), cold (4°C) and drought (PEG2000, 20%) treated plant samples. A total of 251,145 transcripts (N50 = 1,269 bp) and 184,280 unigenes (N50 = 923 bp) were predicted, which code for homologs of near 47% of the published maize proteome. Under cold conditions, 2,232 and 817 genes were up-regulated and down-regulated, respectively, while fewer genes were up-regulated (532) and down-regulated (82) under drought stress, indicating that Zea mays ssp. mexicana L. is more sensitive to the applied cold rather than to the applied drought stresses. Functional enrichment analyses identified many common or specific biological processes and gene sets in response to drought and cold stresses. The ABA dependent pathway, trehalose synthetic pathway and the ICE1-CBF pathway were up-regulated by both stresses. GA associated genes have been shown to differentially regulate the responses to cold in close subspecies in Zea mays. These findings and the identified functional genes can provide useful clues for improving abiotic stress tolerance of maize.

  6. Phytoremediation potential of maize (Zea mays L.) in co-contaminated soils with pentachlorophenol and cadmium.

    Science.gov (United States)

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

    2013-01-01

    The ubiquitous coexistence of heavy metals and organic contaminants was increased in the polluted soil and phytoremediation as a remedial technology and management option is recommended to solve the problems of co-contamination. Growth of Zea mays L and pollutant removal ability may be influenced by interactions among mixed pollutants. Pot-culture experiments were conduced to investigate the single and interactive effect of cadmium (Cd) and pentachlorophenol (PCP) on growth of Zea mays L, PCP, and Cd removal from soil. Growth response of Zea mays L is considerably influenced by interaction of Cd and PCP, significantly declining with either Cd or PCP additions. The dissipation of PCP in soils was notably affected by interactions of Cd, PCP, and plant presence or absence. At the Pentachlorophenol in both planted and non-planted soil was greatly decreased at the end of the 10-week culture, accounting for 16-20% of initial extractable concentrations in non-planted soil and 9-14% in planted soil. With the increment of Cd level, residual pentachlorophenol in the planted soil tended to increase. The pentachlorophenol residual in the presence of high concentration of Cd was even higher in the planted soil than that in the non-planted soil.

  7. Induction of infection in Teosinte (Zea diploperennis through the phytopathogen Ustilago maydis.

    Directory of Open Access Journals (Sweden)

    Martha Concepción Pérez Díaz

    2017-01-01

    Full Text Available Introduction: The corn and teosinte share morphological and molecular similarities latter being those that support the theory of teosinte (Zea parviglumis as its predecessor, both species are attacked by specific pathogens like Ustilago maydis. Objective: To analyze the infectious process that presents U. maydis on the variety of the teosinte Zea diploperennis. Materials and Methods: We used the strain of U. maydis FB-D12, which was kept a culture media rich in nutrients (CPES pH 7.0. Viable cells without morphological alterations to the inoculation method of puncture in teosinte seedlings were used. Monitoring of infection was carried out every 24 hours by measuring concentration of chlorophyll and plant tissue through microscopic observation Results: In the seedlings of Zea diploperennis inoculated with U. maydis the symptoms of the infection were presented, wilt and chlorosis in the leaves; The chlorosis was confirmed with the low concentration of chlorophyll 12 days later to the inoculation. In the microscopic observation of cuts of the tissue plant was found mycelium long and branched from the third day of the inoculation, until the appearance of tumors in seedlings of 45 days. Conclusions: The typical signs of infection with Ustilago maydis in the variety of teosinte Zea diploperennis do not differ from those reported for corn. Ustilago maydis presents its full life cycle within the plant, confirming that the diploperennis variety is susceptible.

  8. Structure of the novel monomeric glyoxalase I from Zea mays.

    Science.gov (United States)

    Turra, Gino L; Agostini, Romina B; Fauguel, Carolina M; Presello, Daniel A; Andreo, Carlos S; González, Javier M; Campos-Bermudez, Valeria A

    2015-10-01

    The glyoxalase system is ubiquitous among all forms of life owing to its central role in relieving the cell from the accumulation of methylglyoxal, a toxic metabolic byproduct. In higher plants, this system is upregulated under diverse metabolic stress conditions, such as in the defence response to infection by pathogenic microorganisms. Despite their proven fundamental role in metabolic stresses, plant glyoxalases have been poorly studied. In this work, glyoxalase I from Zea mays has been characterized both biochemically and structurally, thus reporting the first atomic model of a glyoxalase I available from plants. The results indicate that this enzyme comprises a single polypeptide with two structurally similar domains, giving rise to two lateral concavities, one of which harbours a functional nickel(II)-binding active site. The putative function of the remaining cryptic active site remains to be determined.

  9. Influence of calcium phosphate nanoparticles, Piriformospora indica and Glomus mosseae on growth of Zea mays

    Science.gov (United States)

    Rane, Mansi; Bawskar, Manisha; Rathod, Dnyaneshwar; Nagaonkar, Dipali; Rai, Mahendra

    2015-12-01

    In this study, the arbuscular mycorrhizal fungus (G. mosseae) and endosymbiont (P. indica) colonized Zea mays were treated with calcium phosphate nanoparticles (CaPNPs) and evaluated for their plant growth promotion efficiency. It was observed that CaPNPs in combination with both G. mosseae and P. indica are more potent plant growth promoter than independent combinations of CaPNPs + G. mosseae, CaPNPs + P. indica or CaPNPs alone. The fluorimetric studies of treated plants revealed that CaPNPs alone and in combination with P. indica can enhance vitality of Zea mays by improving chlorophyll a content and performance index of treated plants. Hence, we conclude that CaPNPs exhibit synergistic growth promotion, root proliferation and vitality improvement properties along with endosymbiotic and arbuscular mycorrhizal fungi, which after further field trials can be developed as a cost-effective nanofertilizer with pronounced efficiency.

  10. Effects of INH, DNP, 2,4-D and CMU on the photosynthetic activity of barley and maize plants; Efecto de cuatro inhibidores metabolicos (INH, DNP, 2, 4-D y CMU) sobre la actividad fotosintetica de plantular de cebada (Hordeum vulgare L.) y Maiz (Zea mais L.)

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, J.; Prieto, M. P.

    1979-07-01

    Determinations of the rate of photosynthesis were made in barley and maize leaves treated with INH, DNP, 2,4-D or CMU. 1 ppm of the chemicals in nutritive solutions was absorbed by roots during 24 or 48 hours in both dark and light conditions. After this period, photosynthetic activity, compensation point and 14{sup C}O{sub 2} assimilation were determined. Results show that INH increases the rate of photosynthesis, DNP and 2,4-D do not alter it sensibly and CMU acts as a strong inhibitor of photosynthesis. Some possible applications for ths obtention of labelled compounds by biosynthesis are discussed. (Author) 87 refs.

  11. AVALIAÇÃO DE ALGUNS ASPECTOS QUALITATIVOS E QUANTITATIVOS DE CULTIVARES DE MILHO PIPOCA (Zea mays L. QUALITATIVE AND QUANTITATIVE EVALUATION OF POPCORN (Zea mays CULTIVARS

    Directory of Open Access Journals (Sweden)

    Cleso Antônio Patto Pacheco

    2007-09-01

    Full Text Available

    O milho pipoca é muito consumido pela população brasileira, havendo da parte dos pesquisadores e produtores uma procura constante de cultivares mais produtivas e adequadas ao cultivo em escala comercial. Com objetivo de avaliar cultivares de milho de pipoca, conduziu-se um experimento no ano agrícola de 1992/93 na Escola de Agronomia da Universidade Federal de Goiás. O ensaio constituiu-se de 19 tratamentos com 04 repetições no delineamento de blocos ao acaso. Os tratamentos constituíram-se de 19 cultivares, constantes do Ensaio Nacional de Milho Pipoca coordenado pelo CNPMS/EMBRAPA, a seguir relacionadas: H-16, CMS 42 C-I, CMS 42 C-II, CMS 43 C-I, CMS 43 C-II, UNB-2, PIRAPOCA EPAMIG, ZÉLIA-0l, SAM (STA. CECÍLIA, ROGO POP 1, ROGO POP 2, ROGO POP 3, MF 1001, MF 1002, GO 100-P, COLORADO POP 1, COLORADO POP 2, RS-20 e BR-440. Avaliaram-se altura de plantas, altura de inserção da 1ª espiga, % de plantas doentes, índice de espigas, stand final, produção de grãos/ha e o índice de capacidade de expansão (C.E.. A cultivar que apresentou a maior produção de grãos/ha foi a H-16 (2.928 kg/ha, mas teve uma C.E. muito baixa (11,9. Destacou-se o híbrido triplo Zélia - 0l, com uma capacidade de expansão 22,1 e uma produção de 1.770 kg/ha, 12% mais produtiva do que a testemunha S.A.M. (1.492 kg/ha e C.E.= 15,5, a mais plantada no Brasil. Observou-se uma forte correlação positiva entre a produção com a época de florescimento feminino, índice de espigas, altura de plantas e de espigas. Não foi observada nenhuma correlação entre a capacidade de expansão e os outros caracteres estudados.

    PALAVRAS-CHAVE: Milho-de-pipoca; cultivar; Zea mays.

    Mutational effects of space flight on Zea mays seeds

    Science.gov (United States)

    Mei, M.; Qiu, Y.; He, Y.; Bucker, H.; Yang, C. H.

    1994-01-01

    The growth and development of more than 500 Zea mays seeds flown on Long Duration Exposure Facility (LDEF) were studied. Somatic mutations, including white-yellow stripes on leaves, dwarfing, change of leaf sheath color or seedling color were observed in plants developed from these seeds. When the frequency of white-yellow formation was used as the endpoint and compared with data from ground based studies, the dose to which maize seeds might be exposed during the flight was estimated to be equivalent to 635 cGy of gamma rays. Seeds from one particular holder gave a high mutation frequency and a wide mutation spectrum. White-yellow stripes on leaves were also found in some of the inbred progenies from plants displayed somatic mutation. Electron microscopy studies showed that the damage of chloroplast development in the white-yellow stripe on leaves was similar between seeds flown on LDEF and that irradiated by accelerated heavy ions on ground.

  12. RAPD and internal transcribed spacer sequence analyses reveal Zea nicaraguensis as a section Luxuriantes species close to Zea luxurians.

    Science.gov (United States)

    Wang, Pei; Lu, Yanli; Zheng, Mingmin; Rong, Tingzhao; Tang, Qilin

    2011-04-15

    Genetic relationship of a newly discovered teosinte from Nicaragua, Zea nicaraguensis with waterlogging tolerance, was determined based on randomly amplified polymorphic DNA (RAPD) markers and the internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA using 14 accessions from Zea species. RAPD analysis showed that a total of 5,303 fragments were produced by 136 random decamer primers, of which 84.86% bands were polymorphic. RAPD-based UPGMA analysis demonstrated that the genus Zea can be divided into section Luxuriantes including Zea diploperennis, Zea luxurians, Zea perennis and Zea nicaraguensis, and section Zea including Zea mays ssp. mexicana, Zea mays ssp. parviglumis, Zea mays ssp. huehuetenangensis and Zea mays ssp. mays. ITS sequence analysis showed the lengths of the entire ITS region of the 14 taxa in Zea varied from 597 to 605 bp. The average GC content was 67.8%. In addition to the insertion/deletions, 78 variable sites were recorded in the total ITS region with 47 in ITS1, 5 in 5.8S, and 26 in ITS2. Sequences of these taxa were analyzed with neighbor-joining (NJ) and maximum parsimony (MP) methods to construct the phylogenetic trees, selecting Tripsacum dactyloides L. as the outgroup. The phylogenetic relationships of Zea species inferred from the ITS sequences are highly concordant with the RAPD evidence that resolved two major subgenus clades. Both RAPD and ITS sequence analyses indicate that Zea nicaraguensis is more closely related to Zea luxurians than the other teosintes and cultivated maize, which should be regarded as a section Luxuriantes species.

  13. RAPD and internal transcribed spacer sequence analyses reveal Zea nicaraguensis as a section Luxuriantes species close to Zea luxurians.

    Directory of Open Access Journals (Sweden)

    Pei Wang

    Full Text Available Genetic relationship of a newly discovered teosinte from Nicaragua, Zea nicaraguensis with waterlogging tolerance, was determined based on randomly amplified polymorphic DNA (RAPD markers and the internal transcribed spacer (ITS sequences of nuclear ribosomal DNA using 14 accessions from Zea species. RAPD analysis showed that a total of 5,303 fragments were produced by 136 random decamer primers, of which 84.86% bands were polymorphic. RAPD-based UPGMA analysis demonstrated that the genus Zea can be divided into section Luxuriantes including Zea diploperennis, Zea luxurians, Zea perennis and Zea nicaraguensis, and section Zea including Zea mays ssp. mexicana, Zea mays ssp. parviglumis, Zea mays ssp. huehuetenangensis and Zea mays ssp. mays. ITS sequence analysis showed the lengths of the entire ITS region of the 14 taxa in Zea varied from 597 to 605 bp. The average GC content was 67.8%. In addition to the insertion/deletions, 78 variable sites were recorded in the total ITS region with 47 in ITS1, 5 in 5.8S, and 26 in ITS2. Sequences of these taxa were analyzed with neighbor-joining (NJ and maximum parsimony (MP methods to construct the phylogenetic trees, selecting Tripsacum dactyloides L. as the outgroup. The phylogenetic relationships of Zea species inferred from the ITS sequences are highly concordant with the RAPD evidence that resolved two major subgenus clades. Both RAPD and ITS sequence analyses indicate that Zea nicaraguensis is more closely related to Zea luxurians than the other teosintes and cultivated maize, which should be regarded as a section Luxuriantes species.

  14. Teosinte inflorescence phytolith assemblages mirror Zea taxonomy.

    Directory of Open Access Journals (Sweden)

    John P Hart

    Full Text Available Molecular DNA analyses of the New World grass (Poaceae genus Zea, comprising five species, has resolved taxonomic issues including the most likely teosinte progenitor (Zea mays ssp. parviglumis of maize (Zea mays ssp. mays. However, archaeologically, little is known about the use of teosinte by humans both prior to and after the domestication of maize. One potential line of evidence to explore these relationships is opaline phytoliths produced in teosinte fruit cases. Here we use multidimensional scaling and multiple discriminant analyses to determine if rondel phytolith assemblages from teosinte fruitcases reflect teosinte taxonomy. Our results indicate that rondel phytolith assemblages from the various taxa, including subspecies, can be statistically discriminated. This indicates that it will be possible to investigate the archaeological histories of teosinte use pending the recovery of appropriate samples.

  15. Teosinte inflorescence phytolith assemblages mirror Zea taxonomy.

    Science.gov (United States)

    Hart, John P; Matson, R G; Thompson, Robert G; Blake, Michael

    2011-03-30

    Molecular DNA analyses of the New World grass (Poaceae) genus Zea, comprising five species, has resolved taxonomic issues including the most likely teosinte progenitor (Zea mays ssp. parviglumis) of maize (Zea mays ssp. mays). However, archaeologically, little is known about the use of teosinte by humans both prior to and after the domestication of maize. One potential line of evidence to explore these relationships is opaline phytoliths produced in teosinte fruit cases. Here we use multidimensional scaling and multiple discriminant analyses to determine if rondel phytolith assemblages from teosinte fruitcases reflect teosinte taxonomy. Our results indicate that rondel phytolith assemblages from the various taxa, including subspecies, can be statistically discriminated. This indicates that it will be possible to investigate the archaeological histories of teosinte use pending the recovery of appropriate samples.

  16. Bt Maize Seed Mixtures for Helicoverpa zea (Lepidoptera: Noctuidae): Larval Movement, Development, and Survival on Non-transgenic Maize.

    Science.gov (United States)

    Burkness, Eric C; Cira, T M; Moser, S E; Hutchison, W D

    2015-12-01

    In 2012 and 2013, field trials were conducted near Rosemount, MN, to assess the movement and development of Helicoverpa zea (Boddie) larvae on non-Bt refuge corn plants within a seed mixture of non-Bt and Bt corn. The Bt corn hybrid expressed three Bt toxins-Cry1Ab, Cry1F, and Vip3A. As the use of seed mixtures for insect resistance management (IRM) continues to be implemented, it is necessary to further characterize how this IRM approach impacts resistance development in ear-feeding Lepidopteran pests. The potential for Bt pollen movement and cross pollination of the non-Bt ears in a seed mixture may lead to Bt toxin exposure to larvae developing on those refuge ears. Larval movement and development by H. zea, feeding on non-Bt refuge plants adjacent to either transgenic Bt or non-Bt plants, were measured to investigate the potential for unintended Bt exposure. Non-Bt plants were infested with H. zea eggs and subplots were destructively sampled twice per week within each treatment to assess larval development, location, and kernel injury. Results indicate that H. zea larval movement between plants is relatively low, ranging from 2-16% of larvae, and occurs mainly after reaching the second instar. Refuge plants in seed mixtures did not produce equivalent numbers of H. zea larvae, kernel injury, and larval development differed as compared with a pure stand of non-Bt plants. This suggests that there may be costs to larvae developing on refuge plants within seed mixtures and additional studies are warranted to define potential impacts.

  17. Quality Protein Maize Response to Nitrogen Rate and Plant Density ...

    African Journals Online (AJOL)

    Quality Protein Maize Response to Nitrogen Rate and Plant Density in the Guinea Savanna Zone of Ghana. ... protein maize (Zea mays L.) hybrid to plant density and nitrogen (N) fertilizer. ... Optimal N rate was not affected by plant density.

  18. Alternative respiratory path capacity in plant mitochondria: effect of growth temperature, the electrochemical gradient, and assay pH. [Zea mays L. , Vigna radiata L. , Symplocarpus foetidus L. , Sauromatum guttatum Schott

    Energy Technology Data Exchange (ETDEWEB)

    Elthon, T.E.; Stewart, C.R.; McCoy, C.A.; Bonner, W.D. Jr.

    1986-02-01

    Influence of growth temperature on the capacity of the mitochondrial alternative pathway of electron transport was investigated using etiolated corn (Zea mays L.) seedlings. These seedlings were grown to comparable size in either a warm (30/sup 0/C) or a cold (13/sup 0/C) temperature regime, and then their respiration rates were measured as O/sub 2/ uptake at 25/sup 0/C. The capacity of the alternative pathway (KCN-insensitive O/sub 2/ uptake) was found essentially to double in shoots of cold-grown seedlings. When mitochondria were isolated from the shoots a greater potential for flow through the alternative path was observed in mitochondria from the cold-grown seedlings with all substrates used (an average increase of 84%). Using exogenous NADH as the substrate, the effect of the electrochemical gradient on measurable capacities of the cytochrome and alternative pathways was investigated in mitochondria from both etiolated seedlings and thermogenic spadices. In corn shoot and mung bean (Vigna radiata L.) hypocotyl mitochondria increased flow through the cytochrome chain in the absence of the electrochemical gradient was found not to influence the potential for flow through the alternative path. However, in mitochondria from skunk cabbage (Symplocarpus foetidus L.) and voodoo lily (Sauromatum gutatum Schott) spadices increased flow through the cytochrome chain in the absence of the gradient occurred at the expense of flow through the alternative pathway. This experiment also revealed that the potential for respiratory control is largely dependent upon the assay pH.

  19. MORDIDA: EM QUEM DÓI MAIS?

    Directory of Open Access Journals (Sweden)

    FERREIRA, A.L.N.

    2015-12-01

    Full Text Available O início da vida escolar da criança é marcante tanto para pais quanto para professores. É comum que ao ingressar no ambiente escolar, as crianças vivenciem novas experiências e relações sociais distantes do ambiente familiar, demonstrando assim comportamentos, tais como: choro, timidez e mordidas. O presente trabalho tem como objetivo analisar a opinião dos pais e responsáveis de crianças na faixa etária de 18 meses a 2 anos em relação à mordida no ambiente escolar. Diante esta situação, a psicóloga clínica e escolar Hennemann (2004 explica: “Esta é uma manifestação de desenvolvimento considerada impulsiva e exploratória”. Este comportamento aparece e desaparece à medida que a criança amadurece e encontra outras formas de exploração do ambiente. Freud (1920 explica que a fase oral é o período em que a criança sente necessidade de levar à boca tudo o que estiver ao seu alcance, pois o prazer vital está ligado à nutrição. Ela experimenta o mundo com o que conhece melhor: a boca. Outra razão é a necessidade de se comunicar. A metodologia utilizada nesse trabalho utilizou a abordagem qualitativa e quantitativa. Foram analisadas 26 entrevistas realizadas com os pais dos alunos do pré-maternal do CENSA. O período de adaptação escolar é o período em que as mordidas mais acontecem por isso nessa época sua intervenção deve ser maior. Diante dos resultados obtidos, observamos que muitos pais apesar de entender que a mordida faz parte desta faixa etária, mostram-se desconfortáveis com esta situação e buscam junto à escola, estratégias capazes de minimizar esta atitude da criança. Não veem a mordida como algo natural, mas também não supervalorizam o ato como violência. Buscam entender o contexto onde geralmente aconteceu a situação e agem junto aos professores, seguindo as orientações da escola. Constatamos que a parceria entre escola e família é o elemento fundamental para garantir que esta

  1. Conservation and diversity of seed associated endophytes in Zea across boundaries of evolution, ethnography and ecology.

    Science.gov (United States)

    Johnston-Monje, David; Raizada, Manish N

    2011-01-01

    Endophytes are non-pathogenic microbes living inside plants. We asked whether endophytic species were conserved in the agriculturally important plant genus Zea as it became domesticated from its wild ancestors (teosinte) to modern maize (corn) and moved from Mexico to Canada. Kernels from populations of four different teosintes and 10 different maize varieties were screened for endophytic bacteria by culturing, cloning and DNA fingerprinting using terminal restriction fragment length polymorphism (TRFLP) of 16S rDNA. Principle component analysis of TRFLP data showed that seed endophyte community composition varied in relation to plant host phylogeny. However, there was a core microbiota of endophytes that was conserved in Zea seeds across boundaries of evolution, ethnography and ecology. The majority of seed endophytes in the wild ancestor persist today in domesticated maize, though ancient selection against the hard fruitcase surrounding seeds may have altered the abundance of endophytes. Four TRFLP signals including two predicted to represent Clostridium and Paenibacillus species were conserved across all Zea genotypes, while culturing showed that Enterobacter, Methylobacteria, Pantoea and Pseudomonas species were widespread, with γ-proteobacteria being the prevalent class. Twenty-six different genera were cultured, and these were evaluated for their ability to stimulate plant growth, grow on nitrogen-free media, solubilize phosphate, sequester iron, secrete RNAse, antagonize pathogens, catabolize the precursor of ethylene, produce auxin and acetoin/butanediol. Of these traits, phosphate solubilization and production of acetoin/butanediol were the most commonly observed. An isolate from the giant Mexican landrace Mixteco, with 100% identity to Burkholderia phytofirmans, significantly promoted shoot potato biomass. GFP tagging and maize stem injection confirmed that several seed endophytes could spread systemically through the plant. One seed isolate

  2. Conservation and diversity of seed associated endophytes in Zea across boundaries of evolution, ethnography and ecology.

    Directory of Open Access Journals (Sweden)

    David Johnston-Monje

    Full Text Available Endophytes are non-pathogenic microbes living inside plants. We asked whether endophytic species were conserved in the agriculturally important plant genus Zea as it became domesticated from its wild ancestors (teosinte to modern maize (corn and moved from Mexico to Canada. Kernels from populations of four different teosintes and 10 different maize varieties were screened for endophytic bacteria by culturing, cloning and DNA fingerprinting using terminal restriction fragment length polymorphism (TRFLP of 16S rDNA. Principle component analysis of TRFLP data showed that seed endophyte community composition varied in relation to plant host phylogeny. However, there was a core microbiota of endophytes that was conserved in Zea seeds across boundaries of evolution, ethnography and ecology. The majority of seed endophytes in the wild ancestor persist today in domesticated maize, though ancient selection against the hard fruitcase surrounding seeds may have altered the abundance of endophytes. Four TRFLP signals including two predicted to represent Clostridium and Paenibacillus species were conserved across all Zea genotypes, while culturing showed that Enterobacter, Methylobacteria, Pantoea and Pseudomonas species were widespread, with γ-proteobacteria being the prevalent class. Twenty-six different genera were cultured, and these were evaluated for their ability to stimulate plant growth, grow on nitrogen-free media, solubilize phosphate, sequester iron, secrete RNAse, antagonize pathogens, catabolize the precursor of ethylene, produce auxin and acetoin/butanediol. Of these traits, phosphate solubilization and production of acetoin/butanediol were the most commonly observed. An isolate from the giant Mexican landrace Mixteco, with 100% identity to Burkholderia phytofirmans, significantly promoted shoot potato biomass. GFP tagging and maize stem injection confirmed that several seed endophytes could spread systemically through the plant. One seed

  3. Unraveling the role of dark septate endophyte (DSE) colonizing maize (Zea mays) under cadmium stress: physiological, cytological and genic aspects

    OpenAIRE

    Jun-ling Wang; Tao Li; Gao-yuan Liu; Joshua M. Smith; Zhi-wei Zhao

    2016-01-01

    A growing body of evidence suggests that plant root-associated fungi such as dark septate endophytes (DSE) can help plants overcome many biotic and abiotic stresses, of great interest is DSE-plant metal tolerance and alleviation capabilities on contaminated soils. However, the tolerance and alleviation mechanisms involved have not yet been elucidated. In the current study, the regulation and physiological response of Zea mays to its root-associated DSE, Exophiala pisciphila was analyzed under...

  4. Effect of emamectin benzoate on mortality, proboscis extension, gustation and reproduction of the corn earworm, Helicoverpa zea

    Science.gov (United States)

    Newly emerged bollworm adults, Helicoverpa zea (Boddie) require carbohydrate source from plant exudates and nectars for reproduction. Adults actively seek such feeding sites upon eclosion in their natural habitat. We wanted to evaluate this nocturnal behavior of the bollworm for potential use as a p...

  5. Embryogenesis in Zea mays L. A structural approach to maize caryopsis development in vivo and in vitro.

    NARCIS (Netherlands)

    Lammeren, van A.A.M.

    1987-01-01

    In this thesis the embryological development of the maize plant ( Zeamays L.) is described. The investigations aim at analysing the development of polarity, the initiation of meristems, the differentiation of tissues within the embryo and the interaction between the embryo and the extr

  6. Effect of emamectin benzoate on mortality, proboscis extension, gustation and reproduction of the corn earworm, Helicoverpa zea.

    Science.gov (United States)

    López, Juan D; Latheef, M A; Hoffmann, W C

    2010-01-01

    Newly emerged corn earworm adults, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) require a carbohydrate source from plant or other exudates and nectars for dispersal and reproduction. Adults actively seek and forage at feeding sites upon eclosion in the habitat of the larval host plant or during dispersal to, or colonization of, a suitable reproductive habitat. This nocturnal behavior of H. zea has potential for exploitation as a pest management strategy for suppression using an adult feeding approach. This approach entails the use of a feeding attractant and stimulant in combination with a toxicant that when ingested by the adult will either reduce fecundity/fertility at sub-lethal dosages or kill the adult. The intent of this study was to assess reproductive inhibition and toxicity of emamectin benzoate on H. zea when ingested by the adults when mixed in ppm active ingredient (wt:vol) with 2.5 M sucrose as a feeding stimulant. Because the mixture has to be ingested to function, the effect of emamectin benzoate was also evaluated at sub-lethal and lethal concentrations on proboscis extension and gustatory response of H. zea in the laboratory. Feral males captured in sex pheromone-baited traps in the field were used for toxicity evaluations because they were readily available and were more representative of the field populations than laboratory-reared adults. Laboratory-reared female moths were used for reproduction effects because it is very difficult to collect newly emerged feral females from the field. Emamectin benzoate was highly toxic to feral H. zea males with LC(50) values (95% CL) being 0.718 (0.532-0.878), 0.525 (0.316-0.751), and 0.182 (0.06-0.294) ppm for 24, 48 and 72 h responses, respectively. Sub-lethal concentrations of emamectin benzoate did not significantly reduce proboscis extension response of feral males and gustatory response of female H. zea. Sublethal concentrations of emamectin benzoate significantly reduced percent larval hatch of

  7. Influência da idade dos ovos de Helicoverpa zea (Boddie no parasitismo de Trichogramma pretiosum Riley Influence of egg age of Helicoverpa zea (Boddie on the parasitism by Trichogramma pretiosum Riley

    Directory of Open Access Journals (Sweden)

    Dirceu Pratissoli

    1999-05-01

    Full Text Available Entre os agentes de controle biológico, os parasitóides do gênero Trichogramma representam um dos mais importantes grupos, pois controlam diversas pragas na agricultura. Este trabalho teve por objetivo determinar a melhor idade dos ovos de Helicoverpa zea (Boddie para que Trichogramma pretiosum Riley tenha uma melhor eficiência no controle dessa praga. Ovos com um, dois, três e quatro dias foram oferecidos para o parasitismo, por um período de 24 horas a 25 ± 1ºC, umidade relativa de 70 ± 10% e fotofase de 14 horas. Ovos de um dia de idade apresentaram a maior taxa de parasitismo, viabilidade e número de descendentes por fêmea. A mais alta eficiência de T. pretiosum será alçancada no campo, quando for observado maior densidade de ovos de H. zea com, no máximo, dois dias de desenvolvimento embrionário.Among the agents of biological control, the parasitoids of the genus Trichogramma represent one of the most important groups, as they are able to control many pests in agriculture. The objective of this work was to determine the best age of the Helicoverpa zea (Boddie eggs so that the Trichogramma pretiosum Riley could have the best efficiency against this pest. One, two, three and four-days-old eggs were offered for the parasitism during 24 hours, at 25 ± 1ºC, relative humidity 70 ± 10% and photofase of 14 hours. One-day-old eggs showed the highest rates of parasitism, viability, and number of descendants for each female. The highest efficiency with T. pretiosum will be reached in the field conditions, when observed a great density of H. zea eggs until two days of embryonic development.

  8. High-efficiency perovskite solar cells prepared by using a sandwich structure MAI-PbI2-MAI precursor film.

    Science.gov (United States)

    Zhang, Xuhui; Ye, Jiajiu; Zhu, Liangzheng; Zheng, Haiying; Liu, Guozhen; Liu, Xuepeng; Duan, Bin; Pan, Xu; Dai, Songyuan

    2017-01-11

    Two-step deposition has been widely used in the perovskite layer preparation for perovskite solar cells due to its attractive morphology controllability. However, the limited diffusivity of CH3NH3I (MAI) might cause some PbI2 to remain in the perovskite film. The residual PbI2 in the perovskite film would lead to inferior performance of devices, such as, low power conversion efficiency (PCE), poor reproducibility and weak air stability. In this work, we developed a sandwich structure MAI-PbI2-MAI precursor film to prepare a PbI2-free CH3NH3PbI3 perovskite film. In comparison to the two-step approach, the MAI-PbI2-MAI precursor film with a typical sandwich structure formed a uniform and pinhole-free perovskite film without any PbI2 residue, which could significantly improve the performance of the devices. Moreover, the bottom MAI layer of the MAI-PbI2-MAI precursor film could improve the interfacial contact of the porous TiO2 layer, leading to the promotion of the charge transfer and reduction of the recombination rate. Therefore, the devices fabricated from the sandwich structure MAI-PbI2-MAI precursor films showed dramatic improvements of open-circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF) and PCE. As a result, a promising PCE of 17.8% with good long-term air stability was achieved for the MAI-PbI2-MAI precursor film based PSC, which is better than that prepared by a two-step approach.

  9. Activity and multiple forms of peroxidase in Zea mays and Medicago sativa treated and non-treated with lead

    Energy Technology Data Exchange (ETDEWEB)

    Maier, R.

    1978-02-11

    The influence of lead on peroxidase was studied in young plants of Zee mays and Medicago sativa grown in solutions of Pb(NO/sub 3/)/sub 2/. The content of nitrate in the control- and the lead-solutions was equalized by NaNO/sub 3/. In the patterns of the multiple forms in roots and leaves of Zea and Medicago qualitatively no, or respectively negligible, change between control and lead-treated plants takes place. The temperature during the lead-treatment does not effect the numbers and the positions of bands. The bands' activity of peroxidase in lead-treated plants differs clearly from untreated plants, resulting in a different activity of the whole enzyme. In the roots and in the leaves of Zea as well as in the leaves of Medicago the relative activity of the peroxidase in lead-treated plants is raised. In the roots of Medicago the relative activity decreased slightly.

  10. Efeitos da densidade e proporção de plantas de milho (Zea mays L. e caruru (Amaranhus retroflexus L. em competição Density and porportion effects among corn (Zea mays L. and pigweed (Amaranthus retroflexus L. under competition

    Directory of Open Access Journals (Sweden)

    Pedro J. Christoffoleti

    1996-01-01

    Full Text Available A maioria dos estudos de competição, entre plantas daninhas e cultivadas, conduzidos nos últimos anos, procuram quantificar a interferência que as plantas daninhas causam sobre as culturas; no entanto, poucos destes trabalhos estudam mecanisticamente os efeitos da densidade e da proporção de plantas em uma mistura de espécies, a importância da competição intra e interespecífica e a diferenciação de nicho ecológico. Desta forma, foi desenvolvida a presente pesquisa com o objetivo principal de descrever as interações competitivas e os índices de competitividade entre plantas de milho (Zea mays L. e caruru (Amarathus retroflexus L.. A metodologia utilizada foi a de um experimento substitutivo com densidade total de 400 plantas/m2 e 5 proporções, além da monocultura que variou de 50 a 800 plantas/m2, sendo conduzido no delineamento experimental de blocos casualizados, com quatro repetições. Os resultados obtidos foram analisados pelo método convencional de análise de experimentos substitutivos e pelo método da produção recíproca total e por planta. O milho foi um competidor muito mais agressivo que o caruru, sendo que para a planta cultivada a competição intraespecífica é mais importante que a competição interespecífica. O contrário é verdadeiro para o caruru, ou seja, a competição interespecífica é mais importante que a intraespecífica. Ambas espécies de plantas estão competindo pelos mesmos fatores de crescimento, pois o índice que mede a diferenciação de nicho ecológico é menor que 1,0. A determinação da influência da densidade e proporção de espécies em estudos de competição entre plantas é muito importante para a compreensão das interações competitivas.Most of the competition studies between weeds and crops conducted lately quantify the interference that the weeds cause to crops; however, these researches do not show mechanistically neither the effects of density and proportion of

  11. Study Interactions of Competition between Climbing Common Bean (Phaseolus vulgaris L. and Corn (Zea mays L. Plants Sowed Associate Relaciones de Competencia entre el Fríjol Trepador (Phaseolus vulgaris L. y el Maíz (Zea mays L. Sembrados en Asocio

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    León Darío Vélez Vargas

    2011-12-01

    Full Text Available Associated corn and bean is one of several systems to produce climbing bean. The main characteristic of the associated is the greater yield by area than monoculture of two species, although the competence between them reduces the yield bean in 40% and 20% in corn. Research about physiological processes affected by competence between these species is still scarce. The objective of this research was to evaluate the effects of competence on the physiological behavior of bean. In a randomized block design with 4 replications were established the following treatments: bean without competition, competition between bean and maíze by light, competition between bean and maíze by soil resources and simultaneous competition between bean and maíze by both resources light and soil. The variables measured were accumulated dry matter and its accumulation rate, leaf area, stem longitude, and the yield components of bean. The variance analysis, comparison of means and simple correlations were used. The types of competition significantly reduced the accumulated dry matter, the rates of accumulation, the yield and the yield components. The types of competence did not show significant differences on seed weigh and accumulated total dry matter of plants. Although during the plants ontogeny there were significant differences between them, feedback processes were established within each type of competition. Therefore, the effects of competence in the final stage were not distinguished. It suggests that bean plant is an integrated unit through the physiological processes.Una forma de cultivar fríjol trepador es en asocio con maíz. Su principal característica es el mayor rendimiento por unidad de área con respecto a los unicultivos de cada especie, aunque la competencia que se presenta entre ellas reduce los rendimientos del fríjol en más del 40% y los de maíz en 20%. La investigación sobre los procesos fisiológicos afectados por la competencia y su din

  12. Iron oxide nanoparticles coated with β-cyclodextrin polluted of Zea mays plantlets

    Directory of Open Access Journals (Sweden)

    Mihaela Racuciu

    2012-01-01

    Full Text Available The present experimental investigation is focused on the study of assimilatory pigments and nucleic acid levels in young plants intended for agricultural use (Zea mays in presence of water based magnetic fluid added in culture medium. The magnetic fluid was constituted by coating the nanosized magnetic nanoparticles (with 10.55 nm average value of the physical diameter with β-cyclodextrin (C42H70O35 and further dispersion in water. After germination, various volume fractions (between 10 mL/L and 500 mL/L of the magnetic fluid was added daily in the culture medium of Zea mays plants still at their early ontogenetic stages. Toxicity symptoms leaded to brown spots covering the leaf surface for the highest magnetic fluid volume fractions used, a putative oxidative stress generated by iron excess treatment. Relatively small volume fraction of magnetic fluid solutions induced the increase of chlorophyll a level (up to 38%, the main photosynthesis pigment, as well that the nucleic acid level (up to 57% in Zea mays plantlets. All volume fractions of magnetic fluid solutions analyzed may have severe disruptive effects such as the ratio chlorophyll a/chlorophyll b (about 50% decreasing.

  13. Urinary deoxynivalenol (DON) and zearalenone (ZEA) as biomarkers of DON and ZEA exposure of pigs.

    Science.gov (United States)

    Thanner, S; Czeglédi, L; Schwartz-Zimmermann, H E; Berthiller, F; Gutzwiller, A

    2016-05-01

    Four diets contaminated with 1.1 to 5.0 mg/kg deoxynivalenol (DON) and 0.4 to 2.4 mg/kg zearalenone (ZEA) were fed to four groups of six growing Large White pigs. Urine samples were collected after 3 to 4 days and again after 6 to 7 days on the diets. On each sampling day, half of the animals were sampled in the morning, after an 8-h fast, and the other half were sampled in the afternoon, after 7 h of ad libitum access to feed. The urinary concentrations of DON, DON-glucuronide, DON-3-sulphate, de-epoxy-DON, as well as of ZEA, ZEA-14-glucuronide, α-zearalenol and α-zearalenol-14-glucuronide, analysed using LC-MS/MS, were used to calculate urinary DON and ZEA equivalent concentrations (DONe and ZEAe). The urinary concentration of DONe (P < 0.001), but not of ZEAe (P = 0.31), was lower in the fasted than that in the fed animals. The urinary DONe/creatinine and ZEAe/creatinine ratios were highly correlated with DON and ZEA intake per kg body weight the day preceding sampling (r = 0.76 and 0.77; P < 0.001). The correlations between DON intake during the 7 h preceding urine sampling in the afternoon and urinary DONe/creatinine ratio (r = 0.88) as well as between mean ZEA intake during 3 days preceding urine sampling and urinary ZEAe/creatinine ratio (r = 0.84) were even higher, reflecting the plasma elimination half-time of several hours for DON and of more than 3 days for ZEA. ZEAe analysed in enzymatically hydrolysed urine using an ELISA kit was highly correlated with the LC-MS/MS data (r = 0.94). The urinary DONe and ZEAe to creatinine ratios, analysed in pooled urine samples of several pigs fed the same diet, can be used to estimate their exposure to DON and ZEA.

  14. Bioavailability and toxicity of arsenic in maize (Zea mays L.) grown in contaminated soils.

    Science.gov (United States)

    Drličková, Gabriela; Vaculík, Marek; Matejkovič, Peter; Lux, Alexander

    2013-08-01

    The growth of maize (Zea mays L.), hybrid Valentina, was compared in two types of contaminated soil substrates (Ochre and Heap) with different arsenic (As) concentration originating from an old mining area in Slovakia. Although the total As concentration in Heap soil was 2.6 times lower than in Ochre soil (90 and 237 mg kg⁻¹, respectively), plants grown in Heap soil accumulated more As in their tissues (shoot and root As concentration being 4 and 5.5 times higher, respectively) and were markedly smaller, which produced significantly less biomass and flowered later in comparison with Ochre soil grown plants.

  15. Growth promotion of peanut (Arachis hypogaea L.) and maize (Zea mays L.) plants by single and mixed cultures of efficient phosphate solubilizing bacteria that are tolerant to abiotic stress and pesticides.

    Science.gov (United States)

    Anzuay, María Soledad; Ciancio, María Gabriela Ruiz; Ludueña, Liliana Mercedes; Angelini, Jorge Guillermo; Barros, Germán; Pastor, Nicolás; Taurian, Tania

    2017-06-01

    The aims of this study were, to analyze in vitro phosphate solubilization activity of six native peanut bacteria and to determine the effect of single and mixed inoculation of these bacteria on peanut and maize plants. Ability to produce organic acids and cofactor PQQ, to solubilize FePO4 and AlPO4 and phosphatase activity were analyzed. Also, the ability to solubilize phosphate under abiotic stress and in the presence of pesticides of the selected bacteria was determined. The effect of single and mixed bacterial inocula was analyzed on seed germination, maize plant growth and in a crop rotation plant assay with peanut and maize. The six strains produced gluconic acid and five released cofactor PQQ into the medium. All bacteria showed ability to solubilize phosphate from FePO4 and AlPO4 and phosphatase activity. The ability of the bacteria to solubilize tricalcium phosphate under abiotic stress and in presence of pesticides indicated encouraging results. Bacterial inoculation on peanut and maize increased seed germination, plant́s growth and P content. Phosphate solubilizing bacteria used in this study showed efficient phosphate mineralizing and solubilization ability and would be potential P-biofertilizers for peanut and maize. Copyright © 2017 Elsevier GmbH. All rights reserved.

  16. Valor nutritivo de plantas de milho (Zea mays L. sem espigas - DOI: 10.4025/actascianimsci.v27i4.1145 Nutritional value of corn plants (Zea mays L. without ears - DOI: 10.4025/actascianimsci.v27i4.1145

    Directory of Open Access Journals (Sweden)

    Jean-Claude Emile

    2005-03-01

    Full Text Available A composição químico-bromatológica e a digestibilidade in vitro de cinco genótipos de milho (F2, Lu16, F271, Lu5 e Lu6 foram avaliados em Druelle-France, em parcelas de 150 m2 com duas repetições. O delineamento experimental utilizado foi em blocos ao acaso. Todas as avaliações do estudo foram realizadas em plantas inteiras sem espigas. O genótipo Lu16 foi o que apresentou os maiores valores para a digestibilidade da matéria seca (69,82% e digestibilidade da parede celular (48,05%. O genótipo Lu6 apresentou o menor valor para a digestibilidade in vitro da matéria seca (50,38%. Os teores de digestibilidade da matéria seca e da parede celular foram estimados por método indireto e foram afetados negativamente pelos teores de lignina, ácido p-cumárico e de ácidos ferúlicos totais, que servem de pontes para ligações fortes ou fracas entre ligninas e hemiceluloses. Por meio de análises de regressão múltiplas, verificou-se que a fração fibra em detergente ácido e a lignina em detergente ácido explicaram 98% dos resultados referentes à digestibilidade in vitro da matéria seca e 96% dos resultados referentes à digestibilidade da parede celular estimada por equação. O ácido p-cumárico esterificado e a lignina em detergente ácido explicaram 99% dos resultados referentes à digestibilidade da parede celularChemical-bromatologic composition and in vitro digestibility of five corn genotypes (F2, Lu16, F271, Lu5 and Lu6 were evaluated in Druelle-France, an area of in 150 m2 with two repetitions. All evaluations used whole corn plants without ears. A randomized experimental design was used. The Lu16 genotype showed higher values for in vitro dry matter digestibility (69.82% and cell wall digestibility (48.05%. Lu6 genotype showed the lowest value for in vitro dry matter digestibility (50.38%. Dry matter and cell wall digestibility were estimated by an indirect method and they were negatively affected by lignin contents, p

  17. Production of haploid plants from ten hybrids of bread wheat (Triticum aestivum L. through wide hybridization with maize (Zea mays L. Producción de plantas haploides a partir de 10 híbridos de trigo para pan (Triticum aestivum L. mediante hibridación interespecífica con maíz (Zea mays L.

    Directory of Open Access Journals (Sweden)

    L.E. Torres

    2010-12-01

    Full Text Available The aim of this work was to obtain haploid plants of bread wheat through wide hybridization with maize. The experimental material included ten bread wheat hybrids (female parent and one population of maize (pollen donor. Two assays were carried out in two different seasons (summer and winter. Wheat spikes were manually emasculated, each spike was pollinated twice with fresh pollen of maize and a solution of 2,4-D (100 mg l-1 was sprayed on pollinated florets and injected in the upper internode. Fifteen and 21 days after pollination caryopses were removed and surface sterilized. Embryos were cultured in tubes containing B5 medium. The ten hybrid combinations produced caryopses, but only eight of these hybrids produced embryos and, in six of them, the recovered embryos developed into haploid plantlets. The results showed that there is genotypic influence of the wheat parents on the percentage of haploid embryo formation, in accordance with the results obtained by other authors. Regardless of the genotype, the sowing season and the harvest date, 69.4% of the pollinated flowers gave place to the formation of caryopses, 5.5% of these caryopses developed into presumably haploid embryos (for their morphological phenotypes and 26.1 % of the recovered embryos developed into haploid plantlets.El objetivo del presente trabajo fue obtener plantas haploides de trigo para pan mediante hibridación interespecífica con maíz. Se utilizaron 10 híbridos de trigo para pan (madre y una población de maíz (donante de polen; se llevaron a cabo dos ensayos en distintas estaciones de cultivo. Cada espiga de trigo fue emasculada manualmente y polinizada dos veces con polen fresco de maíz; las flores polinizadas se pulverizaron con una solución de 2,4-D (100 mg l-1, la que también se inyectó en la base de la espiga. Las semillas se cosecharon a los 15 y 21 días posteriores a la polinización. Los embriones recuperados se colocaron en tubos conteniendo medio de

  18. Use of Zea mays L. in phytoremediation of trichloroethylene.

    Science.gov (United States)

    Moccia, Emanuele; Intiso, Adriano; Cicatelli, Angela; Proto, Antonio; Guarino, Francesco; Iannece, Patrizia; Castiglione, Stefano; Rossi, Federico

    2017-04-01

    Trichloroethylene (TCE) is a chlorinated aliphatic organic compound often detected as pollutant in soils and ground water. "Green technologies" based on phytoremediation were proven to be effective to reclaim organic pollutants (e.g. TCE) and heavy metals from different environmental matrices. In this work, we use Zea mays L. for the removal of high TCE concentrations from medium cultures. In particular, we investigated a sealed bioreactor where the growth medium was contaminated with an increasing amount of TCE, in the range 55-280 mg/L; the removal capability of the maize plants was assessed by means of GC-MS and LC-MS analyses. An accurate mass balance of the system revealed that the plants were able to remove and metabolise TCE with an efficiency up to 20 %, depending on the total amount of TCE delivered in the bioreactor. Morphometric data showed that the growth of Z. mays is not significantly affected by the presence of the pollutant up to a concentration of 280 mg/L, while plants show significant alterations at higher TCE concentrations until the growth is completely inhibited for [TCE] ≃ 2000 mg/L. Finally, the presence of several TCE metabolites, including dichloroacetic and trichloroacetic acids, was detected in the roots and in the aerial part of the plants, revealing that Z. mays follows the green liver metabolic model. These results encourage further studies for the employment of this plant species in phytoremediation processes of soils and waters contaminated by TCE and, potentially, by many other chlorinated solvents.

  19. Arsenic accumulation in maize crop (Zea mays): a review.

    Science.gov (United States)

    Rosas-Castor, J M; Guzmán-Mar, J L; Hernández-Ramírez, A; Garza-González, M T; Hinojosa-Reyes, L

    2014-08-01

    Arsenic (As) is a metalloid that may represent a serious environmental threat, due to its wide abundance and the high toxicity particularly of its inorganic forms. The use of arsenic-contaminated groundwater for irrigation purposes in crop fields elevates the arsenic concentration in topsoil and its phytoavailability for crops. The transfer of arsenic through the crops-soil-water system is one of the more important pathways of human exposure. According to the Food and Agriculture Organization of the United Nations, maize (Zea mays L.) is the most cultivated cereal in the world. This cereal constitutes a staple food for humans in the most of the developing countries in Latin America, Africa, and Asia. Thus, this review summarizes the existing literature concerning the conditions involved in agricultural soil that leads to As influx into maize crops and the uptake mechanisms, metabolism and phytotoxicity of As in corn plants. Additionally, the studies of the As accumulation in raw corn grain and corn food are summarized, and the As biotransfer into the human diet is highlighted. Due to high As levels found in editable plant part for livestock and humans, the As uptake by corn crop through water-soil-maize system may represent an important pathway of As exposure in countries with high maize consumption.

  20. Nascent transcription affected by RNA polymerase IV in Zea mays.

    Science.gov (United States)

    Erhard, Karl F; Talbot, Joy-El R B; Deans, Natalie C; McClish, Allison E; Hollick, Jay B

    2015-04-01

    All eukaryotes use three DNA-dependent RNA polymerases (RNAPs) to create cellular RNAs from DNA templates. Plants have additional RNAPs related to Pol II, but their evolutionary role(s) remain largely unknown. Zea mays (maize) RNA polymerase D1 (RPD1), the largest subunit of RNA polymerase IV (Pol IV), is required for normal plant development, paramutation, transcriptional repression of certain transposable elements (TEs), and transcriptional regulation of specific alleles. Here, we define the nascent transcriptomes of rpd1 mutant and wild-type (WT) seedlings using global run-on sequencing (GRO-seq) to identify the broader targets of RPD1-based regulation. Comparisons of WT and rpd1 mutant GRO-seq profiles indicate that Pol IV globally affects transcription at both transcriptional start sites and immediately downstream of polyadenylation addition sites. We found no evidence of divergent transcription from gene promoters as seen in mammalian GRO-seq profiles. Statistical comparisons identify genes and TEs whose transcription is affected by RPD1. Most examples of significant increases in genic antisense transcription appear to be initiated by 3'-proximal long terminal repeat retrotransposons. These results indicate that maize Pol IV specifies Pol II-based transcriptional regulation for specific regions of the maize genome including genes having developmental significance.

  1. Comparative toxicity of mycotoxins to navel orangeworm (Amyelois transitella) and corn earworm (Helicoverpa zea).

    Science.gov (United States)

    Niu, Guodong; Siegel, Joel; Schuler, Mary A; Berenbaum, May R

    2009-08-01

    Mycotoxins, such as aflatoxins and ochratoxins, are widely distributed in nature and are frequently problematic crop contaminants that cause millions of dollars of annual losses in the United States. Insect infestations of crop plants significantly exacerbate mycotoxin contamination. Damage to a variety of nut species by Amyelois transitella Walker (navel orangeworm, NOW) is associated with infection by Aspergillus species and concomitant production of aflatoxins and ochratoxins. Resistance to aflatoxins in this lepidopteran is compared here with the levels of resistance in Helicoverpa zea (corn earworm, CEW), another lepidopteran that routinely encounters aflatoxins in its diet, albeit at lower levels. Measured as the developmental delay caused by aflatoxin B1 (AFB1), it is apparent that the LC(50) (defined as the concentration preventing 50% of newly hatched larvae from entering the 2nd instar within 48 h) for AFB1 is 100 times greater for A. transitella than for H. zea. Similarly, A. transitella 1st instars display substantially higher tolerance to ochratoxin A, another mycotoxin contaminant produced by Aspergillus species, than do H. zea. Our studies indicate that A. transitella, although a hostplant generalist, may well be highly specialized for mycotoxin detoxification.

  2. Leopoldo Zea e o movimento latino-americano de História das idéias Leopoldo Zea and the Latin-American movement of History of Ideas

    Directory of Open Access Journals (Sweden)

    Eugênio Rezende de Carvalho

    2010-06-01

    Full Text Available O artigo analisa as etapas de fundação e consolidação de um dos mais importantes movimentos intelectuais da América Latina no século XX - o movimento latino-americano de História das Ideias -, a partir, sobretudo, das ações e escritos de seu principal líder e fundador, o filósofo mexicano Leopoldo Zea Aguilar (1912-2004. Na etapa de fundação, que corresponde à década de 1940, o foco principal é na obra inicial de Zea, bem como em seus primeiros esforços no sentido da articulação e organização institucional do movimento em escala continental. Já na etapa seguinte, que corresponde à década de 1950, é abordado o processo de consolidação orgânica e epistemológica do movimento.This article analyzes the stages of foundation and consolidation of one of the most important intellectual movements of Latin America in the twentieth century - the Latin-American movement of History of Ideas -, starting from actions and writings of its main leader and founder, the Mexican philosopher Leopoldo Zea Aguilar (1912-2004. In the 1940s, during the foundation period, the main focus is on the primary work of Zea, as well as on his first efforts to articulate and organize this movement in continental scale. Moreover, in the following stage held in the 1950s, the process of organic and epistemology consolidation of the movement is invoked.

  3. Multifunctional coating MAI D5 intended for the protection of refractory materials

    Science.gov (United States)

    Zhestkov, B. E.; Terent'eva, V. S.

    2010-01-01

    A thin-layer heterophase MAI D5 coating intended for the protection of carbon-containing composite materials (C-C-, C-SiC-, SiC-SiC-composite material) and refractory metal-based alloys against high-temperature gas corrosion and erosion is tested. The coating is formed from a specially developed Si-Ti-Mo-B-Y microcomposition powder material. A new approach to creating self-healing heterophase coatings is used. At operating temperatures, the structure and phase composition of the MAI D5 coating provides rapid self-healing of random defects on the coating surface and in the base material owing to the presence of a silicon-containing eutectic, which favors rapid recovery of a protective amorphous silica layer consumed during operation. Under operating conditions, the coating undergoes self-organization to form a multilayer system with a number of functional oxide micro-, submicro-, and nanolayers. Samples with the MAI D5 coating are subjected to combined tests on bench plants located at MAI and TsAGI under conditions emulating the re-entry of a hypersonic aircraft, when its surface temperature reaches 2400 K. Certification tests are performed in wind tunnels located at TsAGI during a simultaneous action of a hypersonic dissociated-air flow and mechanical loads. The protection of heat-loaded structural elements in space vehicles made of ultrahigh-temperature materials against high-temperature gas corrosion and erosion by the MAI D5 coating in hypersonic dissociated-air flows is shown to be efficient.

  4. Comparisons on Forage Yield and Feeding Value Between Zea mexicana,Yucao2 and Chuandan14-Zea mexicana Hybrid%玉草2号、川单14×墨西哥大刍草和墨西哥大刍草产量和饲用价值比较

    Institute of Scientific and Technical Information of China (English)

    冯云超; 唐祈林; 荣廷昭

    2011-01-01

    To understand the forage yields in different planting density as well as their feeding value in the optimum density, a field experiment which Zea mexicana and Zea mays -Zea mexicana hybrids (Yucao2 and Chuan-danl4 × Zea mexicana) used as the materials were designed by random block split plot design investigated. The main results were that the fresh and dry matter yields of the three forages, which showed the change of "low-high-low" with the increase of planting density. The fresh and dry matter yields were the highest in the Yucao2 and the lowest in Zea mexicana among all planting density. The yields of crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF) and ether extract(EE) in Yucao2 and chuandanl4× Zea Mexicana were higher than in Zea mexicana significantly or high significant, however, the content of CP and EE was the highest in Zea Mexicana. The relative feeding value(RFV) in Yucao2 had no significance with that in Zea mexicana and were higher than in chuandanl4 × Zea mexicana significantly.%采用裂区设计,对不同种植密度下玉草2号、川单14×墨西哥大刍草和墨西哥大刍草产量以及最适密度下饲用价值进行研究.结果表明,在试验设计的密度下,玉草2号鲜、干草产量均最高,川单14×墨西哥大刍草其次,墨西哥大刍草最低;3种饲草其鲜、干草产量随密度增加呈"低-高-低"的变化趋势.最适密度下饲用价值比较表明,玉草2号和川单14×墨西哥大刍草粗蛋白、酸性洗涤纤维、中性洗涤纤维和粗脂肪4种饲用成分产量均显著或极显著高于墨西哥大刍草,其粗蛋白和粗脂肪含量均低于墨西哥大刍草;玉草2号和墨西哥大刍草相对饲用价值差异不显著,均显著高于川单14×墨西哥大刍草.

  5. Fourier transform infrared spectral analysis of maize (Zea mays) plants under zinc deficiency stress%缺锌玉米植株的傅立叶变换红外光谱研究

    Institute of Scientific and Technical Information of China (English)

    王盛锋; 刘云霞; 高丽丽; 韩亚; 黄金生; Hilman; 刘荣乐; 汪洪

    2014-01-01

    锌导致玉米植株生长受抑,利用FTIR技术研究发现缺锌植株中碳水化合物、脂类、蛋白质及核酸组分发生变化,农大108植株中各组分变化受缺锌影响较大,品种农大108可能较郑单958对缺锌更为敏感。%[Objectives]Fourier transform infrared spectroscopy ( FTIR) is a structural analysis technique based on the vibrations of functional group and polar bond in chemical components. The objective of this study was to reveal the component changes in different organs of maize plants with and without zinc( Zn) application using FTIR. It would provide some physiological evidences of maize plants subjected to Zn deficiency stress.[Methods]Two maize cultivars, Nongda108 and Zhengdan958, were chosen as tested crops. Hydroponic culture experiments were conducted with 0 and 1. 0 μmol/L Zn treatments. The plant shoot and root biomass were weighted. Dry plant samples were digested with HNO3 -HClO4 ( 3:1 ) for Zn determination by atomic absorption spectrophotometer. Root samples were stored in FAA solution ( 70% alcohol:38% formaldehyde:acetic acid = 90 :5:5 parts by volume) prior to measurements. The root systems were then digitized with the EsponV700 scanner at 300 dpi resolution for further analysis. The total root length and root volume were measured with WinRHIZO root analysis software ( Regent Instruments Inc. , Canada) . Dry samples of roots, stems and leaves were ground to through 0. 2 mm sieve. A potassium bromide tablet method was used to detect spectral characteristics of different plant parts with FTIR (VERTEX 70, Bruker) and data were collected and analyzed by the OPUS 6. 5 software. [Results]The results show that Zn concentrations in maize plants without Zn application are below the critical level of 20 μg/g, and the Zn deficiency stress significantly decreases shoot dry matter weight, root surface, root volume and total root length. The shoot biomass and root length of maize cultivar, Nongda108, are less than those

  6. FERTILIZER APPLICATION METHODS AND IRRIGATION LEVELS ON EARLY (Zea mays L. DEVELOPMENT FORMAS DE APLICAÇÃO DO FERTILIZANTE E NÍVEIS DE IRRIGAÇÃO NO DESENVOLVIMENTO DO MILHO (Zea mays

    Directory of Open Access Journals (Sweden)

    Jorge Luiz do Nascimento

    2007-09-01

    Full Text Available

    Early corn development (Zea mays L. was evaluated through roots (MR and tops (MA dry matter in a low tunnel greenhouse pot experiment, in a 2x2x4 factorial completely randomized design with three replications, comparing the following treatments: two Oxisols (a sandy Latossolo Vermelho Escuro — LE and a clay Latossolo Roxo - LR; two methods of fertilizer application (soil mixed - A1, and furrow planting line - A2, and four irrigation levels (0%, 15%, 30%, and 45% deficit in relation to the evapotranspired water. Significant effects were observed for fertilizer application methods and irrigation levels on MA, with 89,6% higher yield for A2, and MA reduction for increased water stress. There was a significant interaction between soil types and fertilizer application methods on MA, with a larger MA in the LE soil for A1 method, while MA was larger in the LR soil for A2 method. For MR, it was observed a significant effect of soil type and fertilizer application methods, with a larger yield in the LR soil under the A2 form. The findings confirm the importance of adequate soil water supply for nutrient absorption processes, resulting in better plant development. The localized fertilizer application is recommended for Oxisols with higher clay contents and larger phosphorus fixation capacity.

    KEY-WORDS: Fertilizer; irrigation levels; Zea mays.

    O desenvolvimento inicial da cultura do milho (Zea mays L. foi avaliado através da

  7. Dynamics of phosphorus fractions in the rhizosphere of fababean (Phaseolus vulgaris L.) and maize (Zea mays L.) grown in calcareous and acid soils

    NARCIS (Netherlands)

    Li, G.; Li, Haigang; Leffelaar, P.A.; Shen, J.; Zhang, F.

    2015-01-01

    The dynamics of soil phosphorus (P) fractions were investigated, in the rhizosphere of fababean (Vicia faba L.) and maize (Zea mays L.) grown in calcareous and acid soils. Plants were grown in a mini-rhizotron with a thin (3 mm) soil layer, which was in contact with the root-mat, and considered as r

  8. Pengelolaan Hara Kalium Berdasarkan Batas Kritis Untuk Tanaman Jagung (Zea mays L.) Pada Berbagai Status Hara di Tanah Inceptisol

    OpenAIRE

    Putra, Irwan Agusnu

    2011-01-01

    IRWAN AGUSNU PUTRA, 2010. Potassium Based Nutrient Management of Critical Level For Maize (Zea mays L.) at Various Nutrient Status in the Inceptisol Soil. Under his guidance, Dr. Ir. Hamidah Hanum, MP as Chairman of the Commission of Advisors with members Dr. Ir. Chairani Hanum, MP. In North Sumatra, most of the planting area of corn in the ground Inceptisol widespread, also dominated by the relatively high clay content so that the fixation of potassium are very strong which resulted in the c...

  9. THE INFLUENCE OF GRAMOXONE HERBICIDE ON THE CONTENT OF THE PHOTOSYNTHETIC PIGMENTS IN ZEA MAYS

    Directory of Open Access Journals (Sweden)

    Antoanela Patras

    2007-08-01

    Full Text Available The active substance of Gramoxone herbicide is interacting with plant’s photosynthetic systems, playing the role of final acceptor of the photosynthetic electrons. Except this known mode of action, it has been also observed the inhibitory action on the protoporphyrinogen oxidase – essential enzyme for chlorophylls biosynthesis, and also the decrease of photosynthetic pigment’s concentration in some spontaneous plants. Based on these prerequisites, the present study demonstrates the decrease of the photosynthetic pigment’s content in Zea mays in the presence of Gramoxone.

  10. Zinc toxicity on antioxidative response in (Zea mays L. at two different pH

    Directory of Open Access Journals (Sweden)

    Hosseini, Zahra

    2013-02-01

    Full Text Available Zn is the second most abundant transition metal after iron (Fe. Excess Zn can have negative effects on plants. The effect of Zn at two different pH on lipid peroxidation (MDA, membrane permeability (EC, hydrogen peroxide (H2O2,non-protein thiols (NPT and the activities of major antioxidant enzymes Zea mays were investigated under controlled growth conditions. Zn-excess conditions increased the EC, MDA, H2O2 content and non-protein thiols and also activities of antioxidant enzymes were increased. Also zinc toxicity was higher in 4.5 pH than 7.5 pH.

  11. Sistemas de control de malezas en maiz (Zea mays L.: efecto de metodos de control, densidad y distribucion del cultivo Weed control systems in corn: effects of control methods, density and plant distribution

    Directory of Open Access Journals (Sweden)

    G. Martinez

    1982-12-01

    realización de una escarda adicional no mejora significativamente el control de malezas, no afectando tampoco la incidencia de enfermedades, ni el desarrollo del cultivo, por lo cual resulta innecesaria. Las escardas tienen como principal efecto eliminar la interfe rencia presentada por las malezas y si éstas son eliminadas de otra manera, la realización de aquéllas no apareja beneficios significativos.An experiment was conducted at the Research Station of the University of Chapingo (Mexico (2250 m above sea level, average annual rainfall 550 mm( loamy soil, 1,7% O.M., where different cultural practices were combined in order to design a weed control system for corn. The work was done under rainfed conditions and the variables included were: two population densities (44.400 and 66.600 pl/ha, two plant distributions (normal and equidistant and seven weed control methods (cyanazine + alachlor (1,2 + 1,92 kg/ha, atrazine + alachlor (1,2 + 1,44 kg/ha, one cultivation, two cultivations, a weeded check, a weeded check + two cultivations and a weedy check. The main weed species were: pigweed (Amaranthus sp., Lopezia mexicana Jacq., hairy galinsoga (Galin-soga parviflora Cay., Encelia mexicana Mart., Sporobulus poiretti (Roem. et Sch. Hich., and large crabgrass (Digitaria sanguinalis (L. Scop.. The increase in plant population had no effect on the degree of weed control, incidence of diseases and crop growth. The equidistant distribution improved weed control over the normal one, but it also had a nigher incidence of diseases; this, is turn, may have caused the lack of differences in vegetative growth, a lower amount of cobs per ha and the lack of difference in grain yield between the two distributions. Atrazine + alachlor was better than cyanazine + alachlor in terms of weed control, although the difference was statistically observed only for the visual ratings. There were no differences between both chemical treatments in terms of incidence of diseases or their effect on crop

  12. Glucolipids of Zea mays and Pisum sativum

    Energy Technology Data Exchange (ETDEWEB)

    Morohashi, Y.; Bandurski, R.S.

    1976-06-01

    The glucolipids formed upon feeding (U--/sup 14/C)glucose to embryos of Zea mays were partially characterized with respect to: (a) metabolic turnover, (b) acid lability, (c) phosphorus content, (d) chromatographic properties, and (e) hydrolysis products. The chloroform--methanol-soluble-assimilated radioactivity was examined specifically for occurrence of a glycosylated prenol phosphate. With the extraction conditions used, no evidence was found for formation of a glucosylated prenol phosphate. Several, as yet unidentified, acid-labile glucolipids undergoing metabolic turnover were observed. Four diglycerides were characterized as hydrolysis products of a fraction that contained /sup 14/C-glucose and phosphorus, and was subject to metabolic turnover. Examination of the 1-butanol-soluble glucolipids from pea (Pisum sativum) seedlings also demonstrated anionic glucolipids, evidencing metabolic turnover but none with the properties of glucosylated prenol phosphate.

  13. Simulated drought influences oxidative stress in Zea mays seedlings ...

    African Journals Online (AJOL)

    Simulated drought influences oxidative stress in Zea mays seedlings. ... Bayero Journal of Pure and Applied Sciences. Journal Home · ABOUT ... Seedlings were grown for 8 weeks in nursery bags filled with sandy-loam soil in two categories.

  14. NUTRITIVE VALUE OF MAIZE (Zea Mays AND DOLECOUS (Lablab Purpureus AS AFFECTED BY PHOSPHOROUS FERTILIZATION AND INTERCROPPING

    Directory of Open Access Journals (Sweden)

    E.O. AMASAIB

    2012-11-01

    Full Text Available A field experiment was conducted at the Demonstration Farm of University of Khartoum to determine the effect of phosphorous fertilization and intercropping on the nutritive value of Zea mays and Lablab purpureus. The field experiment was arranged as Split Plot Design with four replications. The main plots were (Lablab purpureus as sole crop, Zea mays as sole crop, Lablab purpureus and Zea mays in the mixture. The sub plot treatments were phosphorous fertilization at the rate of (0, 50 and 75 kg P2O5 / ha which were then referred to as P0, P1 and P2 respectively. The plants measured were Lablab purepureus as pure stand, Lablab purepureus in the mixture, Zea mays as the pure stand and the Zea mays in the mixture. Samples of 45 days cut from sowing were used to assess the ash, crude protein (CP, ether extracts (EE, crude fiber (CF, neutral detergent fibre (NDF and dry matter digestibility. The data were statistically analyzed using complete randomized design. The results revealed that intercropping and phosphorous fertilization caused a significant (P<0.05 increased on the CP content and dry matter digestibility of all forages under estimation. Intercropping and phosphorous fertilization caused slight increase on the Ash content for all crops in this study. Moreover, Intercropping and phosphorous fertilization caused a decrease on the CF and NDF content of all forages under estimation but with no significant difference. However, Intercropping caused non–significant effect (P<0.05 on the EE content of Zea mays while, intercropping had a positive influence (P<0.05 on the EE content of Lablab purpureus. The data obtained indicated that phosphorous fertilization caused non–significant effect on the EE content of all crops in this study (P<0.05 except Lablab purpureus in the mixture with Zea mays which increased significantly (P<0.05 by increasing phosphorous level. It can be concluded that intercropping and phosphorous fertilization improved the

  15. Čiurlionis oma ja praeguses ajas / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2010-01-01

    Näitus "Čiurlionis ja tema aeg leedu kunstis" Kumu Kunstimuuseumis 8. augustini 2010. Näituse on koostanud Kaunase Riiklik M. K. Čiurlionise Kunstimuuseum, kuraatorid Kristina Daubarytė ja Mai Levin, kujundaja Mari Kurismaa. 13. mail toimunud seminarist. Leedu ja eesti kunstnike kontaktidest, ühis- ja vahetusnäitustest, Aleksis Ranniti rollist Čiurlionise propageerijana Läänes, Čiurlionise mõjudest

  16. Čiurlionis oma ja praeguses ajas / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2010-01-01

    Näitus "Čiurlionis ja tema aeg leedu kunstis" Kumu Kunstimuuseumis 8. augustini 2010. Näituse on koostanud Kaunase Riiklik M. K. Čiurlionise Kunstimuuseum, kuraatorid Kristina Daubarytė ja Mai Levin, kujundaja Mari Kurismaa. 13. mail toimunud seminarist. Leedu ja eesti kunstnike kontaktidest, ühis- ja vahetusnäitustest, Aleksis Ranniti rollist Čiurlionise propageerijana Läänes, Čiurlionise mõjudest

  17. Pensionid poliitilisest tõmbetuulest välja / Mai Treial

    Index Scriptorium Estoniae

    Treial, Mai, 1952-

    2007-01-01

    Ilmunud ka: Põhjarannik, 18. mai 2007, lk. 2; Severnoje Poberezhje, 18. mai 2007, lk. 2; Koit, 22. mai 2007, lk. 6; Sakala, 23. mai 2007, lk. 2; Harju Ekspress, 25. mai 2007, lk. 6; Vooremaa, 26. mai 2007, lk. 2; Valgamaalane, 29. mai 2007, lk. 2; Oma Saar, 30. mai 2007, lk. 5; Teataja : Eestimaa Rahvaliidu ajaleht, juuni, nr. 6, 2007, lk. 3. Rahvaliidu ettepanekust riikliku pensionikindlustuse seaduse täiendamise eelnõu kohta: pensioni baasosa osakaalu tuleks suurendada neljal järgmisel aastal

  18. Pensionid poliitilisest tõmbetuulest välja / Mai Treial

    Index Scriptorium Estoniae

    Treial, Mai, 1952-

    2007-01-01

    Ilmunud ka: Põhjarannik, 18. mai 2007, lk. 2; Severnoje Poberezhje, 18. mai 2007, lk. 2; Koit, 22. mai 2007, lk. 6; Sakala, 23. mai 2007, lk. 2; Harju Ekspress, 25. mai 2007, lk. 6; Vooremaa, 26. mai 2007, lk. 2; Valgamaalane, 29. mai 2007, lk. 2; Oma Saar, 30. mai 2007, lk. 5; Teataja : Eestimaa Rahvaliidu ajaleht, juuni, nr. 6, 2007, lk. 3. Rahvaliidu ettepanekust riikliku pensionikindlustuse seaduse täiendamise eelnõu kohta: pensioni baasosa osakaalu tuleks suurendada neljal järgmisel aastal

  19. Increasing incidence of hip fracture in Chiang Mai, Thailand.

    Science.gov (United States)

    Wongtriratanachai, Prasit; Luevitoonvechkij, Sirichai; Songpatanasilp, Thawee; Sribunditkul, Siripoj; Leerapun, Taninnit; Phadungkiat, Sompant; Rojanasthien, Sattaya

    2013-01-01

    Hip fracture is a major health problem in Thailand. This study attempted to examine the incidence, related factors, and trends of hip fracture in Chiang Mai, Thailand. All hip fracture data among patients aged 50 yr or older were collected from hospitals in Chiang Mai, Thailand from August 1, 2006 to July 3, 2007. Data from the 1997 Chiang Mai hip fracture study were used for comparison. In the study period, 690 hip fractures were reported: 203 males and 487 females (male to female ratio was 1 to 2.4), with a mean age of 76.7 yr. The estimated cumulative incidence was 181.0 per 100,000, and the adjusted incidence was 253.3 (males: 135.9; females: 367.9). A simple fall was the most common mechanism (79%) of fracture, and 80% of the hip fractures occurred in patients aged 70 yr or older. The highest incidence of hip fracture was observed in patients older than 85 yr (1239). At 6 mo postfracture, most patients (61%) used a walking aid. Compared with the 1997 data, hip fracture incidence had increased by an average of 2% per yr, and the incidence of hip fracture had increased significantly from August 1, 2006 to July 31, 2007, especially in patients older than 75 yr. In patients older than 84 yr, the incidence increased by a factor of 2. Urgent strategies for the prevention and treatment of osteoporosis, and hence hip fracture, are needed.

  20. Inhibition of Helicoverpa zea (Lepidoptera: Noctuidae) Growth by Transgenic Corn Expressing Bt Toxins and Development of Resistance to Cry1Ab.

    Science.gov (United States)

    Reisig, Dominic D; Reay-Jones, Francis P F

    2015-08-01

    Transgenic corn, Zea mays L., that expresses the Bacillus thuringiensis (Bt) toxin Cry1Ab is only moderately toxic to Helicoverpa zea (Boddie) and has been planted commercially since 1996. Growth and development of H. zea was monitored to determine potential changes in susceptibility to this toxin over time. Small plots of corn hybrids expressing Cry1F, Cry1F × Cry1Ab, Cry1Ab × Cry3Bb1, Cry1A.105 × Cry2Ab2 × Cry3Bb1, Cry1A.105 × Cry2Ab2, and Vip3Aa20 × Cry1Ab × mCry3A were planted in both 2012 and 2013 inNorth and South Carolina with paired non-Bt hybrids from the same genetic background. H. zea larvae were sampled on three time periods from ears and the following factors were measured: kernel area injured (cm(2)) by H. zea larvae, larval number per ear, larval weight, larval length, and larval head width. Pupae were sampled on a single time period and the following factors recorded: number per ear, weight, time to eclosion, and the number that eclosed. There was no reduction in larval weight, number of insect entering the pupal stadium, pupal weight, time to eclosion, and number of pupae able to successfully eclose to adulthood in the hybrid expressing Cry1Ab compared with a non-Bt paired hybrid. As Cry1Ab affected these in 1996, H. zea may be developing resistance to Cry1Ab in corn, although these results are not comprehensive, given the limited sampling period, size, and geography. We also found that the negative impacts on larval growth and development were greater in corn hybrids with pyramided traits compared with single traits.

  1. Effect of zinc on antioxidant response in maize (Zea mays L.) leaves.

    Science.gov (United States)

    Pandey, N; Singh, A K; Pathak, G C; Sharma, C P

    2002-08-01

    Maize (Zea mays L. cv kanaujia) plants grown with Zn [10 (control), 0.1 (low) and 20 microM (high)], were investigated for concentration of antioxidants and activities of antioxidative enzymes in leaves. Young leaves of low Zn plants developed whitish-necrotic spots. Leaves of both low and high Zn plants showed decrease in chlorophyll concentration and accumulation of lipid peroxides, ascorbate and dehydroascorbate, associated with a decrease in the activity of ascorbate peroxidase and superoxide dismutase. Low and high Zn, however, showed diverse effect on glutathione reductase. While low Zn increased the activity of glutathione reductase, high Zn decreased its activity. Zinc effect on antioxidative constituents suggested Zn involvement in sustaining the antioxidative defense system in maize leaves.

  2. Effect of lead on imbibition, germination, and growth of Phaseolus vulgaris L. and Zea mays L.

    Directory of Open Access Journals (Sweden)

    Gustavo Isaza Guzmán Isaza Guzmán

    2013-07-01

    Full Text Available Lead is highly reactive and it can be consequently toxic to living cells to both plants and humans. This heavy metal is a source of contamination to the environment and it disrupts natural cycles. The present study was aimed to evaluate the effect of lead on the imbibition process, germination and growth in the bean (Phaseolus vulgaris L. and maize (Zea mays L.. It was developed a system consisting of receptacles to expose flooded plants at different concentrations of the metal. Results showed that at concentrations of 5 g l-1 lead imbibition process was affected, but was more evident in bean. Germination percentage was not affected in maize seeds, while viability was affected in bean seeds. We observed statistically that there is an effect on organ growth of root, stem and leaf in both species in the presence of solution whose effect is most noticeable in bean plants. Key words: heavy metals,phytoremediation, stress, toxic substances

  3. Responses of Different Physiological Indices for Maize (Zea mays) to Soil Water Availability

    Institute of Scientific and Technical Information of China (English)

    WU Yuan-Zhi; HUANG Ming-Bin; D. N. WARRINGTON

    2011-01-01

    Knowledge of plant responses to soil water availability is essential for the development of efficient irrigation strategies.However,notably different results have been obtained in the past on the responses of various physiological indices for different plants to soil water availability.In this study,the responses of various plant processes to soil water availability were compared with data from pot and field plot experiments conducted on maize (Zea mays L.).Consistent results were obtained between pot and field plot experiments for the responses of various relative plant indices to changes in the fraction of available soil water (FASW).A threshold value,where the relative plant indices began to decrease with soil drying,and a lower water limit,where the decline of relative plant indices changed to a very slow rate,were found.Evaporative demand not only influenced the transpiration rate over a daily scale but also determined the difference in transpirational response to soil water availability among the transient,daily and seasonal time scales.At the seasonal scale,cumulative transpiration decreased linearly with soil drying,but the decrease of transpiration from FASW =1 in response to water deficits did not affect dry weight until FASW =0.75.On the other hand,the decrease in dry weight was comparable with plant height and leaf area.Therefore,the plant responses to soil water availability were notably different among various plant indices of maize and were influenced by the weather conditions.

  4. Effects of Different Nitrogen Application Strategies on Yield and ForageNutritive Quality of Zea mexicana

    Institute of Scientific and Technical Information of China (English)

    WANGYong-jun; WANGKong-jun; YUANCui-ping; XUHong

    2004-01-01

    A pool experiment was carried out to study the effects of different nitrogen application strategies (rates and stages of nitrogen application) on yield and forage nutritive quality of Zea mexicana cultivated in summer, 2002. In the whole growing stage, its stem was clipped three times at the height of 25 cm when it was II0 cm high (H1, H2 and H3 stand for the first, second and third harvest stage, respectively). Six indexes including crude protein (CP), ether extract (EE), nitrogen free extract (NFE), acid detergent fiber (ADF), crude ash (CA), and general energy (GE) were employed to evaluate the forage nutritive value. The results showed that the content of CP and EE increased but the content of CA and ADF decreased under the two nitrogen rates (High-rate N, 600 kg ha-1;Mid-rate N, 300 kg ha-1). The fresh and dry harvest biomass of the whole plants on H1 and those of the leaves on H2 were also improved. But the stalks on H2 and the whole plants on H3 were affected mainly by dressing nitrogen fertilizer. The yield of CP and EE, CA,NFE, and GE was mainly affected by nitrogen rates. The ADF yield increased was due to the increment of the fresh and dry harvest biomass. Nitrogen applied as base fertilizer for summer Zea mexicana can be harvested a higher biomass and improve the forage nutritive quality.

  5. Effects of Different Nitrogen Application Strategies on Yield and Forage Nutritive Quality of Zea mexicana

    Institute of Scientific and Technical Information of China (English)

    WANG Yong-jun; WANG Kong-jun; YUAN Cui-ping; XU Hong

    2004-01-01

    A pool experiment was carried out to study the effects of different nitrogen application strategies (rates and stages of nitrogen application) on yield and forage nutritive quality of Zea mexicana cultivated in summer, 2002. In the whole growing stage, its stem was clipped three times at the height of 25 cm when it was 110 cm high (H1, H2 and H3 stand for the first, second and third harvest stage, respectively). Six indexes including crude protein (CP), ether extract (EE), nitrogen free extract (NFE), acid detergent fiber (ADF), crude ash (CA), and general energy (GE) were employed to evaluate the forage nutritive value. The results showed that the content of CP and EE increased but the content of CA and ADF decreased under the two nitrogen rates (High-rate N, 600 kg ha-1;Mid-rate N, 300 kg ha-1). The fresh and dry harvest biomass of the whole plants on H1 and those of the leaves on H2 were also improved. But the stalks on H2 and the whole plants on H3 were affected mainly by dressing nitrogen fertilizer. The yield of CP and EE, CA,NFE, and GE was mainly affected by nitrogen rates. The ADF yield increased was due to the increment of the fresh and dry harvest biomass. Nitrogen applied as base fertilizer for summer Zea mexicana can be harvested a higher biomass and improve the forage nutritive quality.

  6. Chromium accumulation potential of Zea mays grown under four different fertilizers.

    Science.gov (United States)

    Dheeba, B; Sampathkumar, P; Kannan, K

    2014-12-01

    Chromium (Cr) contamination in soil is a growing concern in sustainable agriculture production and food safety. We performed pot experiment with chromium (30 mg/soil) to assess the accumulation potential of Zea mays and study the influence of four fertilizers, viz. Farm Yard Manure (FYM), NPK, Panchakavya (PK) and Vermicompost (VC) with respect to Cr accumulation. The oxidative stress and pigment (chlorophyll) levels were also examined. The results showed increased accumulation of chromium in both shoots and roots of Zea mays under FYM and NPK supply, and reduced with PK and VC. While the protein and pigment contents decreased in Cr treated plants, the fertilizers substantiated the loss to overcome the stress. Similarly, accumulation of Cr increased the levels of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) indicating the enhanced damage control activity. However, these levels were relatively low in plants supplemented with fertilizers. Our results confirm that the maize can play an effective role in bioremediation of soils polluted with chromium, particularly in supplementation with fertilizers such as farm yard manure and NPK.

  7. Determination of Some Agronomıcal Characteristics of Local Flint Corn (Zea mays L. indurata) Genotypes in The Black Sea Region of Turkey

    OpenAIRE

    2014-01-01

    In this study, 84 flint corn (Zea mays L. indurata) genotypes were used. Twelwe agronomical characteristics of 84 flint local corn genotypes were examined. Local corn genotypes were collected from 12 cities in the Black Sea Region in 2008 and field and laboratuary studies were completed in 2009. Variance analysis showed that there were high variations in most of the agronomical characteristics. At this study, plant height, ear height, stalk diameter, number of leaf per plant, ear length, ear ...

  8. Determination of Some Agronomıcal Characteristics of Local Flint Corn (Zea mays L. indurata) Genotypes in The Black Sea Region of Turkey

    OpenAIRE

    ONER, Fatih; GULUMSER, Ali

    2014-01-01

    In this study, 84 flint corn (Zea mays L. indurata) genotypes were used. Twelwe agronomical characteristics of 84 flint local corn genotypes were examined. Local corn genotypes were collected from 12 cities in the Black Sea Region in 2008 and field and laboratuary studies were completed in 2009. Variance analysis showed that there were high variations in most of the agronomical characteristics. At this study, plant height, ear height, stalk diameter, number of leaf per plant, ear length, ear ...

  9. Biological effects of pollution and problems of the environment in the region of Birsesti (Town of Jiu), Romania. [Triticum vulgare; Zea mays; Brassica oleracea; Vitis vinifera

    Energy Technology Data Exchange (ETDEWEB)

    Ionescu, A.; Neamu, G.

    1973-01-01

    The vegetation around Birsesti showed diminished chlorophyll pigment by as much as 20% below control plants. In Triticum vulgare, Zea mays and Brassica oleracea there was a reduction in functioning stomata. The mechanical blockage by cement dust induced changes in the leaf veins. Plant productivity and dry weight were reduced. A reduction of 250% in Vitis vinifera cultivation was reduced to about 1/3 that of unaffected areas. 16 references, 7 figures, 1 table.

  10. Miks on Savisaar ja proua Bush Birma kallal / Mai Loog

    Index Scriptorium Estoniae

    Loog, Mai, 1960-

    2007-01-01

    Ilmunud ka: Postimees : na russkom jazõke 29. mai lk. 7. Birma sõjaväeline valitsus otsustas taas pikendada aasta võrra Nobeli rahupreemia laureaadi ja demokraatliku opositsiooni liidri Aung San Suu Kyi 11-aastast koduaresti, mille vastu astusid välja USA senaatorid presidendiproua Laura Bushi juhtimisel kui ka Tallinna linnapea Edgar Savisaar koos Pariisi ja Rooma linnapeadega. Birma hunta plaanitavast konstitutsioonist, kus aatomienergia on pandud riigikaitse ja julgeoleku alla. Venemaa aatomienergia agentuuri Rosatomi lepingust Birma huntaga aatomienergia tootmiseks

  11. Modeling of MAI in UWB System Using MGGD

    KAUST Repository

    Ahmed, Qasim Zeeshan

    2014-01-06

    Multivariate generalized Gaussian density (MGGD) is used to approximate the multiple access interference (MAI) and additive white Gaussian noise in pulse-based ultrawide bandwidth (UWB) system. The MGGD probability density function (pdf) is shown to be a better approximation of a UWB system as compared to Gaussian, Laplacian and Gaussian-Laplacian mixture (GLM). The similarity between the simulated and the approximated pdf is measured with the help of modified Kullback-Leibler distance (KLD). It is also shown that MGGD has the smallest KLD as compared to Gaussian, Laplacian and GLM densities. Finally, a receiver based on the principles of minimum bit error rate is designed for the MGGD pdf.

  12. Miks on Savisaar ja proua Bush Birma kallal / Mai Loog

    Index Scriptorium Estoniae

    Loog, Mai, 1960-

    2007-01-01

    Ilmunud ka: Postimees : na russkom jazõke 29. mai lk. 7. Birma sõjaväeline valitsus otsustas taas pikendada aasta võrra Nobeli rahupreemia laureaadi ja demokraatliku opositsiooni liidri Aung San Suu Kyi 11-aastast koduaresti, mille vastu astusid välja USA senaatorid presidendiproua Laura Bushi juhtimisel kui ka Tallinna linnapea Edgar Savisaar koos Pariisi ja Rooma linnapeadega. Birma hunta plaanitavast konstitutsioonist, kus aatomienergia on pandud riigikaitse ja julgeoleku alla. Venemaa aatomienergia agentuuri Rosatomi lepingust Birma huntaga aatomienergia tootmiseks

  13. Testing the Framework Species Method for Forest Restoration in Chiang Mai, Northern Thailand

    Directory of Open Access Journals (Sweden)

    Prasit WANGPAKAPATTANAWONG

    2008-01-01

    Full Text Available The framework species method of reforestation, developed by FORRU (Forest Restoration Research Unit has been used successfully to restore evergreen forest on degraded former agricultural sites in Doi Suthep-Pui National Park, Chiang Mai province, Thailand. This paper reports 3 year results of an attempt to duplicate the FORRU reforestation techniques at Ban Toong Yah, Mae Chaem district, at a similar elevation as FORRU’s original plots at Ban Mae Sa Mai, Mae Rim district. Twenty species of framework tree seedlings were planted in June 2002. The 2 year results indicate that the seedlings achieved lower survival rates than at the FORRU’s original site. Height growth, root collar diameter, and crown width were also lower. Some seedlings died because they were trampled by cows, which also ate some of the seedlings. However, several sapling species, such as Ficus fistulosa and Phyllanthus emblica, were able to produce new shoots from their axillary buds, after having been browsed by cows. In 2004, 5 well-performed species: Castanopsis tribuloides, Ficus fistulosa, Hovenia dulcis, Ostodes paniculata and Prunus cerasoides, were selected along with 12 never-planted species to be planted in June. The results indicate that the seedlings achieved lower survival rates than at the FORRU’s original site. The seedlings achieved an average survival rate of about 50 % after the first growing season. The exposed, windy environment of the planting site might also account for lower than expected growth and survival rates. The FORRU’s recommended methods of site preparation using herbicide and weed suppression using cardboard mulch may be employed to improve seedling survival and growth on this site.

  14. Recovery of Lead(II from Aqueous Solutions by Zea mays Tassel Biosorption

    Directory of Open Access Journals (Sweden)

    Caliphs M. Zvinowanda

    2010-01-01

    Full Text Available Problem statement: Major adsorbent materials used in heavy metal ion removal from polluted aqueous streams are expensive and difficult to regenerate. In this study, the possibility of using Zea mays tassel, as an alternative low cost biosorbent material to remediate heavy metal pollution was investigated. Lead (II was used because of its wide application in industrial products and well documented toxicity. Approach: Tassel was obtained from mature Zea mays cultivar R52 hybrid plants. The tassel was milled to a powder and was used to adsorb lead(II ions from simulated solutions in batch experiments. The desorption of lead(II was carried out using nitric acid and sodium citrate solutions. The adsorbent was characterized by FTIR, EDX and ESCA before and after application of lead(II solutions. Results: For samples with concentrations of 100 mg L-1 Pb(II, 94-98% was adsorbed and 57-74 and 57-67% recoveries were achieved with 0.5-5 M nitric acid and 0.01-0.2 M sodium citrate as the stripping solutions, respectively. EDX spectrum of pure tassel indicated that group 1 and 2 metals were the major exchangeable ions present on its surface. ESCA analysis picked up small amounts of lead(II in the form of Pb(OH+ and Pb(NH+ ions on the surface of tassel adsorbent exposed to Pb2+ ions and none on pure tassel sample. Functional groups such as -H, -NH2, -C = O and -COOH which are polar and are legends which are capable of binding heavy metals were identified by FTIR. Conclusion: The potential of Zea mays tassel to adsorb and recover heavy metals from aqueous solution was successfully demonstrated with Pb(II sample solutions. The results obtained thus far demonstrated the possibility of using tassel powder in the removal as well as recovery of metals from aqueous solutions.

  15. QTL mapping of resistance to sheath blight in maize (Zea mays L.)

    Institute of Scientific and Technical Information of China (English)

    YANG Hua; YANG Junpin; RONG Tingzhao; TAN Jun; QIU Zhenggao

    2005-01-01

    The genetic linkage map has been constructed with 125 SSR markers based on BC1:2 population consisting of 322 lines derived from the combination of (CML270×478) ×CML270 in maize (Zea mays L.), covering 1939.0 cM of maize genome. The average mapping distance was about 15.5 cM. Three major QTLs of the relative resistant index of resistance to maize sheath blight (Rhizoctonia solani) had been located on chromosomes 1, 7 by composite interval mapping (CIM). 7 QTLs of the plant height have been located on chromosomes 3, 4, 5, 6. Five QTLs of ear height have been located on chromosomes 3, 4, 6. The resistance to the sheath blight is shown to be not relative to plant height and ear height genetically. Inbred line CML270 was used for molecular assisted selection and cloning the genes.

  16. Antimony uptake by Zea mays (L.) and Helianthus annuus (L.) from nutrient solution.

    Science.gov (United States)

    Tschan, Martin; Robinson, Brett; Schulin, Rainer

    2008-04-01

    We investigated the extent of Sb uptake by maize (Zea mays) and sunflower (Helianthus annuus) from nutrient solutions containing concentrations from 3 to 24 mg/L of potassium antimonate, with the aim of determining the potential of Sb to enter the food chain. The maximum shoot Sb concentrations in Z. mays and H. annuus were 41 mg/kg and 77 mg/kg dry weight, respectively. There was no significant difference in Sb uptake between species. The average bioaccumulation coefficients (the plant/solution concentration quotients) were 1.02 and 1.93 for Z. mays and H. annuus, respectively. Phosphate addition did not affect plant growth or Sb uptake. Antimony uptake by both Z. mays and H. annuus is unlikely to pose a health risk to animals and humans.

  17. La relégation (loi du 27 mai 1885

    Directory of Open Access Journals (Sweden)

    Jean-Lucien Sanchez

    2005-01-01

    Full Text Available La loi du 27 mai 1885 (lire le texte, dite loi sur la relégation des récidivistes, entraîne « l’internement perpétuel sur le territoire des colonies ou possessions françaises » des délinquants et criminels multirécidivistes . L’enjeu de cette loi est de « débarrasser » le sol de la France métropolitaine des petits délinquants et vagabonds par une mécanique qui est unique dans l’histoire du droit pénal français. En effet, cette loi établie une « présomption irréfragable d’incorrigibilité », c...

  18. Mixed Reality Cultural Heritage Communication - The Zea Case

    DEFF Research Database (Denmark)

    Veirum, Niels Einar; Christensen, Mogens Fiil; Mayerhofer, Mikkel

    ”. The poster presents an actual experience design case in Zea Harbour, Greece dealing with these challenges using mixed reality communicating cultural heritage material. Archaeological findings, physical reconstructions and digital models are mixed to effectively stage the interactive experience space. The Zea...... Case is a design scenario for the Museum of the Future showing how Cultural Heritage institutions can use a Glocal Approach to technology and architecture to reinvent the relation to the visitor and the neighbourhood. While Mixed Reality can be used for Cultural Heritage Communication in traditional...

  19. In planta gene expression analysis of Xanthomonas oryzae pathovar oryzae, African strain MAI1

    Directory of Open Access Journals (Sweden)

    Verdier Valérie

    2010-06-01

    Full Text Available Abstract Background Bacterial leaf blight causes significant yield losses in rice crops throughout Asia and Africa. Although both the Asian and African strains of the pathogen, Xanthomonas oryzae pv. oryzae (Xoo, induce similar symptoms, they are nevertheless genetically different, with the African strains being more closely related to the Asian X. oryzae pv. oryzicola (Xoc. Results Changes in gene expression of the African Xoo strain MAI1 in the susceptible rice cultivar Nipponbare were profiled, using an SSH Xoo DNA microarray. Microarray hybridization was performed comparing bacteria recovered from plant tissues at 1, 3, and 6 days after inoculation (dai with bacteria grown in vitro. A total of 710 bacterial genes were found to be differentially expressed, with 407 up-regulated and 303 down-regulated. Expression profiling indicated that less than 20% of the 710 bacterial transcripts were induced in the first 24 h after inoculation, whereas 63% were differentially expressed at 6 dai. The 710 differentially expressed genes were one-end sequenced. 535 sequences were obtained from which 147 non-redundant sequences were identified. Differentially expressed genes were related to metabolism, secretion and transport, pathogen adherence to plant tissues, plant cell-wall degradation, IS elements, and virulence. In addition, various other genes encoding proteins with unknown function or showing no similarity to other proteins were also induced. The Xoo MAI1 non-redundant set of sequences was compared against several X. oryzae genomes, revealing a specific group of genes that was present only in MAI1. Numerous IS elements were also found to be differentially expressed. Quantitative real-time PCR confirmed 86% of the identified profile on a set of 14 genes selected according to the microarray analysis. Conclusions This is the first report to compare the expression of Xoo genes in planta across different time points during infection. This work shows that

  20. Cannibalism of Helicoverpa zea (Lepidoptera: Noctuidae) from Bacillus thuringiensis (Bt) transgenic corn versus non-Bt corn.

    Science.gov (United States)

    Chilcutt, Charles F

    2006-06-01

    Because of the importance of cannibalism in population regulation of Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) in corn, Zea mays L., it is useful to understand the interactions between Bacillus thuringiensis (Bt) transgenic corn and cannibalism. To determine the effects of Bt corn on cannibalism in H. zea, pairs of the same or different instars were taken from Bt or non-Bt corn and placed on artificial diet in proximity. Cannibalism occurred in 91% of pairs and was approximately 7% greater for pairs of larvae reared from Bt transgenic corn (95%) than from non-Bt corn (88%). Also, first instar by first instar pairs had a lower rate of cannibalism than other pairs. Time until cannibalism was not different for larvae from Bt corn versus non-Bt corn. Pupation rate of cannibals and surviving victims was not different for pairs from Bt corn versus non-Bt corn. Finally, cannibalism increased pupation rate of cannibals from both Bt and non-Bt corn by approximately 23 and 12%, respectively, although the increases were not significant. Thus, negative effects of Bt on larvae were compensated by increased cannibalism in comparison with larvae reared on non-Bt corn, which increased larval survival to levels comparable with larvae reared on non-Bt plants.

  1. Allocation and source attribution of lead and cadmium in maize (Zea mays L.) impacted by smelting emissions.

    Science.gov (United States)

    Bi, Xiangyang; Feng, Xinbin; Yang, Yuangen; Li, Xiangdong; Shin, Grace P Y; Li, Feili; Qiu, Guangle; Li, Guanghui; Liu, Taoze; Fu, Zhiyou

    2009-03-01

    Plants grown in contaminated areas may accumulate trace metals to a toxic level via their roots and/or leaves. In the present study, we investigated the distribution and sources of Pb and Cd in maize plants (Zea mays L.) grown in a typical zinc smelting impacted area of southwestern China. Results showed that the smelting activities caused significantly elevated concentrations of Pb and Cd in the surrounding soils and maize plants. Pb isotope data revealed that the foliar uptake of atmospheric Pb was the dominant pathway for Pb to the leaf and grain tissues of maize, while Pb in the stalk and root tissues was mainly derived from root uptake. The ratio of Pb to Cd concentrations in the plants indicated that Cd had a different behavior from Pb, with most Cd in the maize plants coming from the soil via root uptake.

  2. Influence of Dual-Bt Protein Corn on Bollworm, Helicoverpa zea (Boddie), Survivorship on Bollgard II Cotton.

    Science.gov (United States)

    Von Kanel, M B; Gore, J; Catchot, A; Cook, D; Musser, F; Caprio, M

    2016-04-01

    Similar Cry proteins are expressed in both Bt corn, Zea mays L., and cotton, Gossypium hirsutum (L.), commercial production systems. At least one generation of corn earworm, Helicoverpa zea (Boddie), completes development on field corn in the Mid-South before dispersing across the landscape into other crop hosts like cotton. A concern is that Bt corn hybrids may result in selection for H. zea populations with a higher probability of causing damage to Bt cotton. The objective of this study was to determine the susceptibility of H. zea offspring from moths that developed on non-Bt and VT Triple Pro (VT3 PRO) field corn to lyophilized Bollgard II cotton tissue expressing Cry1Ac and Cry2Ab. Offspring of individuals reared on VT3 PRO expressing Cry1A.105 and Cry2Ab had a significantly higher LC50 two out of the three years this study was conducted. Excess larvae were placed on artificial diet and allowed to pupate to determine if there were any inheritable fitness costs associated with parental development on VT3 PRO corn. Offspring resulting from males collected from VT3 PRO had significantly lower pupal weight and longer pupal duration compared with offspring of individuals collected from non-Bt corn. However, offspring from females collected from VT3 PRO were not different from non-Bt offspring. Paternal influence on offspring in insects is not commonly observed, but illustrates the side effects of development on a transgenic plant expressing less than a high dose, 25 times the concentration needed to kill susceptible larvae.

  3. Effect of arbuscular mycorrhizal fungi on phytoextraction by corn (Zea mays) of lead-contaminated soil.

    Science.gov (United States)

    Hovsepyan, A; Greipsson, S

    2004-01-01

    The role of arbuscular mycorrhizal fungi (AMF) in lead (Pb) uptake by corn (Zea mays) grown in soil supplemented with Pb was examined. Plants were subjected to four Pb levels: 0 (control); 10 (low); 100 (medium); and 500 mg L(-1) (high). At each Pb level, plants were grown in soil without and with fungicide (benomyl) (20 mg kg(-1)) to suppress AMF activity. Benomyl significantly reduced AMF colonization at high. medium, and zero Pb exposures. Benomyl application resulted in significantly lower concentrations of phosphorus in leaves at low and medium Pb exposures. The benomyl-treated plants had higher Pb and manganese concentrations in leaves than plants not treated with benomyl. In addition, benomyl-treated plants had generally lower concentrations of zinc and copper in leaves than plants not treated with benomyl. These results suggest that the role of AMF in heavy metal uptake is metal specific. Based on this work, the use of benomyl on soils contaminated with Pb can be recommended in phytoextraction.

  4. Precise genome modification in the crop species Zea mays using zinc-finger nucleases.

    Science.gov (United States)

    Shukla, Vipula K; Doyon, Yannick; Miller, Jeffrey C; DeKelver, Russell C; Moehle, Erica A; Worden, Sarah E; Mitchell, Jon C; Arnold, Nicole L; Gopalan, Sunita; Meng, Xiangdong; Choi, Vivian M; Rock, Jeremy M; Wu, Ying-Ying; Katibah, George E; Zhifang, Gao; McCaskill, David; Simpson, Matthew A; Blakeslee, Beth; Greenwalt, Scott A; Butler, Holly J; Hinkley, Sarah J; Zhang, Lei; Rebar, Edward J; Gregory, Philip D; Urnov, Fyodor D

    2009-05-21

    Agricultural biotechnology is limited by the inefficiencies of conventional random mutagenesis and transgenesis. Because targeted genome modification in plants has been intractable, plant trait engineering remains a laborious, time-consuming and unpredictable undertaking. Here we report a broadly applicable, versatile solution to this problem: the use of designed zinc-finger nucleases (ZFNs) that induce a double-stranded break at their target locus. We describe the use of ZFNs to modify endogenous loci in plants of the crop species Zea mays. We show that simultaneous expression of ZFNs and delivery of a simple heterologous donor molecule leads to precise targeted addition of an herbicide-tolerance gene at the intended locus in a significant number of isolated events. ZFN-modified maize plants faithfully transmit these genetic changes to the next generation. Insertional disruption of one target locus, IPK1, results in both herbicide tolerance and the expected alteration of the inositol phosphate profile in developing seeds. ZFNs can be used in any plant species amenable to DNA delivery; our results therefore establish a new strategy for plant genetic manipulation in basic science and agricultural applications.

  5. Climate Change Adaptation: Real Time Nitrogen Management in Maize (Zea Mays L. Using Leaf Colour Chart

    Directory of Open Access Journals (Sweden)

    R. K. Mathukia

    2014-12-01

    Full Text Available A field experiment was conducted at Instructional Farm, College of Agriculture, Junagadh Agricultural University, Junagadh during rabi 2011-12 and 2012-13 to study the real time nitrogen management using leaf colour chart (LCC in maize (Zea mays L.. Basal dose of 20-50 kg N-P2O5/ha was applied in all the treatments. Top dressing of 60 or 80 N in form of Urea in two splits at LCC 2, 3, 4 and 5 were compared with fixed time N application [50 kg N/ha at 30 DAS + 30 kg N/ha at 60 days after sowing (DAS]. Top dressing of 50 kg N/ha + 30 kg N/ha when LCC=4 or LCC=5 significantly improved growth and yield attributes viz., plant height, dry matter accumulation/plant, number of leaves/plant, stem diameter, number of internodes/ plant, leaf area index, cob length, cob girth, number of cobs/plant, number of grains/cob, grain weight/plant and 1000-grain weight along with higher grain and stover yields, grain protein content and economic returns over fixed time application of 50 kg N/ha at 30 DAS + 30 kg N/ha at 60 DAS.

  6. Uptake and accumulation of copper by roots and shoots of maize(Zea may L.)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The effects of different concentrations of copper sulfate on rootand shoot growth of maize(Zea mays L.) and the uptake and accumulation of Cu2+ by its roots and shoots were investigated in the present study. The concentrations of opper sulfate (CuSO4.5H2O) used were in the range of 10-5-10-3mol/L. Root growth decreased progressively with increasing concentration of Cu2+ in solution. The seedlings exposed to 10-3 mol/L Cu exhibited substantial growth reduction, yielding only 68% of the root length of the control. The shoot growth of the seedlings grown at 10-5-10-4 mol/L Cu2+ were more or less than the same as the control seedlings. The leaves treated with 10-3 mol/L Cu2+ were obviously inhibited in shoot growth. The fresh and dry weights both in roots and shots decreased progressively with increasing Cu2+ concentration.This fits well with the above mentioned effects of copper sulfate on root growth. Zea mays has considerable ability to remove Cu from solutions and accumulate it. The Cu content in roots of Z. Mays increased with increasing solution concentration of Cu2+. The amount of Cu in roots of plants treated with 10-3, 10-4 and 10-5 mol/L Cu2+ were 10, 8 and 1.5 fold, respectively, greater than that of roots of control plant. However, the plants transported and concentrated only a small amount of Cu in their shoots.

  7. Zea diploperennis (Gramineae): A New Teosinte from Mexico.

    Science.gov (United States)

    Iltis, H H; Doebley, J F; M, R G; Pazy, B

    1979-01-12

    A perennial teosinte or "wild maize" endemic to the Cerro de San Miguel, Sierra de Manantlan, Jalisco, Mexico differs from Zea perennis by dimorphic rhizomes, robust habit, and a larger number of longer, laxer tassel branches. The fact that it is a diploid (2n = 20) has taxonomic and agronomic significance. The seeds are used locally for food.

  8. Rapid screening for aluminum tolerance in maize (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Carlos Daniel Giaveno

    2000-12-01

    Full Text Available A significant decrease in maize grain yield due to aluminum toxicity is considered to be one of the most important agricultural problems for tropical regions. Genetic improvement is a useful approach to increase maize yield in acid soils, but this requires a rapid and reliable method to discriminate between genotypes. In our work we investigated the feasibility of using hematoxylin staining (HS to detect Al-tolerant plants at the seedling stage. The original population along with two populations obtained after one cycle of divergent selection were evaluated by net root growth (NRG and HS after 7 days in nutrient solution. Results showed a negative correlation between NRG and HS in all populations, in which sensitive plants, characterized by low NRG, exhibited more intense staining than tolerant plants. These results indicate that HS is a useful procedure for selecting Al-tolerant maize seedlings.A importante diminuição nos rendimentos de milho causados pela toxidez produzida pelo alumínio é considerada um dos mais importantes problemas nas regiões tropicais. O melhoramento genético é uma metodologia útil para aumentar os rendimentos do milho em solos ácidos, requerendo um método rápido e seguro que permita diferenciar os diferentes genótipos. O objetivo deste trabalho foi avaliar a possibilidade de utilizar a técnica da coloração com hematoxilina (HS na detecção de plântulas tolerantes ao alumínio. Duas populações obtidas de um ciclo de seleção divergente e a original, foram avaliadas depois de sete dias em solução nutritiva utilizando os parâmetros NRG (crescimento líquido da raiz principal e HS. Os resultados apresentaram uma correlação negativa entre NRG e HS em todas as populações devido ao fato de que as plântulas suscetíveis, caracterizadas por um baixo NRG, apresentaram uma coloração mais intensa do que as tolerantes. Nossos resultados permitem concluir que a técnica de coloração com hematoxilina

  9. Comunicólogo que brinca comunica mais?

    Directory of Open Access Journals (Sweden)

    Ivany Câmara Neiva

    2015-09-01

    CINECLICK (sobre filme Tarja Branca. Disponível em http://www.cineclick.com.br/tarja-branca-a-revolucao-que-faltava. Acesso em 02.08.2015. COMISSÃO DE PROFESSORES. Carta aberta ao Ministro Cid Gomes. Correio Braziliense, Brasília, 10.02.2015. p.3. CORTELLA, Mário Sérgio. Os alunos não são mais os mesmos. In Novos Paradigmas da Educação (vídeo. São Paulo: Atta Mídia e Educação, 2003. D´ÁVILA, Cristina e VEIGA, Ilma Passos Alencastro (orgs.. Didática e docência na educação superior: implicações para a formação de professores. Campinas, SP: Papirus, 2012. DUARTE, Mauricio. O básico do básico. Disponível em http://www.revistadacultura.com.br/revistadacultura/detalhe/14-09-04/A_base_do_b%C3%A1sico.aspx. Acesso em 02.08.2015. DUARTE JUNIOR, João-Francisco. O que é realidade. 10.ed., 5.reimpr. São Paulo: Brasiliense, 2004. (1ª edição: 1984. ______. O sentido dos sentidos: a educação (do sensível. Disponível em http://www.bibli

  10. Influence du décalage du semis du niébé (Vigna unguiculata (L.) Walp) par rapport au maïs (Zea mays L.) sur la croissance et le rendement du niébé

    OpenAIRE

    Osiru, DSO.; Ocaya, CP.; Adipala, E.

    2002-01-01

    Effect of Time of Planting Cowpea (Vigna unguiculata (L.) Walp) Relative to Maize (Zea mays L.) on Growth and Yield of Cowpea. Field investigations were carried out for three seasons in two locations of Uganda to examine yield benefits when cowpea and maize are planted under intensive farming conditions. Additive mixtures of cowpea were planted into maize thrice at 2 weekly intervals together with sole crops. Time of introducing cowpea into maize significantly affected both the growth and yie...

  11. Morphological and physiological responses of maize (Zea mays) exposed to sand contaminated by phenanthrene.

    Science.gov (United States)

    Dupuy, Joan; Ouvrard, Stéphanie; Leglize, Pierre; Sterckeman, Thibault

    2015-04-01

    Phytoremediation is promising, but depends on clearly understanding contaminants' impact on plant functioning. We therefore focused on the impact of polycyclic aromatic hydrocarbons (PAH) on cultivated plants and understanding the impact of phenanthrene (PHE) on maize functioning (Zea mays). Cultivation was conducted under controlled conditions on artificially contaminated sand with PHE levels increasing from 50 to 750 mg PHE kg(-1). After four weeks, plants exposed to levels above 50 mg PHE kg(-1) presented decreased biomasses and reduced photosynthetic activity. These modifications were associated with higher biomass allocations to roots and lower ones to stems. The leaf biomass proportion was similar, with thinner blades than controls. PHE-exposed plant showed modified root architecture, with fewer roots of 0.2 and 0.4 mm in diameter. Leaves were potassium-deplete, but calcium, phosphorus, magnesium and zinc-enriched. Their content in nitrogen, iron, sulfur and manganese was unaffected. These responses resembled those of water-stress, although water contents in plant organs were not affected by PHE and water supply was not limited. They also indicated a possible perturbation of both nutritional functioning and photosynthesis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Biochemical and Photosynthetic Evaluation of Responses in Zea mays L. Under Drought Stress

    Directory of Open Access Journals (Sweden)

    S. S. Abu-Muriefah

    2014-04-01

    Full Text Available Antioxidant defense system(s, pigments content and photosynthetic activity as well as some biochemical changes under drought stress were analyzed in maize (Zea mays L. cv. Giza 21 leaves to determine the response of plant to drought stress and to elucidate the role of various protective mechanisms against oxidative stress. It was found that the application of drought stress led to changes in the carbohydrates and protein contents. Total soluble sugars, accumulated in the leavesof water-stressed plants, whereas, starch and protein contents were dropped to a small amounts compared to the control. Furthermore, plants have well-developed defense systems againstreactive oxygen species (ROS, involving both limiting the formation of ROS as well asinstituting its removal. Within a cell, the activities of a range of antioxidant enzymes suchas superoxide dismutase (SOD, catalase (CAT, ascorbate peroxidase(APX involved in scavenging ROS were investigated. During dehydrationthe SOD, APX and CAT increased significantly up to 4 days, then declined in their activities but still maintained higher than the control levels this indicates that the defense systems involvedare efficient in the protection of plant cells against oxidation. In addition, there was consistent increase in the lipid peroxidation and accumulation of malondialdehyde (MDA. The levels of hydrogen peroxide were also elevated during stressing periods. In this study we are reporting the negative response of maize plants toward drought stress especially on the antioxidant enzymatic activity for the prolonged drought effect.

  13. Small amounts of ammonium (NH4+) can increase growth of maize (Zea mays)

    KAUST Repository

    George, Jessey

    2016-09-16

    Nitrate (NOequation image) and ammonium (NHequation image) are the predominant forms of nitrogen (N) available to plants in agricultural soils. Nitrate concentrations are generally ten times higher than those of NHequation image and this ratio is consistent across a wide range of soil types. The possible contribution of these small concentrations of NHequation image to the overall N budget of crop plants is often overlooked. In this study the importance of this for the growth and nitrogen budget of maize (Zea mays L.) was investigated, using agriculturally relevant concentrations of NHequation image. Maize inbred line B73 was grown hydroponically for 30 d at low (0.5 mM) and sufficient (2.5 mM) levels of NOequation image. Ammonium was added at 0.05 mM and 0.25 mM to both levels of NOequation image. At low NOequation image levels, addition of NHequation image was found to improve the growth of maize plants. This increased plant growth was accompanied by an increase in total N uptake, as well as total phosphorus, sulphur and other micronutrients in the shoot. Ammonium influx was higher than NOequation image influx for all the plants and decreased as the total N in the nutrient medium increased. This study shows that agriculturally relevant proportions of NHequation image supplied in addition to NOequation image can increase growth of maize.

  14. Keanekaragaman Hayati Penyakit – Penyakit yang disebabkan oleh jamur Pada Tanaman Jagung (Zea mays L. ) di Dataran Tinggi dan Rendah di Sumatera Utara

    OpenAIRE

    Damanik, Christin Maria Eleonora

    2011-01-01

    Christin Maria Eleonora Damanik ”Biodiversity of Diseases Caused by Fungy in Corn Plants (Zea mays L.) in Highland and Lowland at North Sumatera”, supervised by Lisnawita and Alm. Kamal Arifin. This research was held in Purwobinangun and Namoukur, Langkat, approximetely ± 118 m from the sea surface and Guru Kinayan, Karo, approximetely ± 1004 m from the sea surface. This research used survey method. Survey was using random sampling for vegetative phase & generative phase. The parameters were...

  15. Oxidation of indole-3-acetic acid to oxindole-3-acetic acid by an enzyme preparation from Zea mays

    Science.gov (United States)

    Reinecke, D. M.; Bandurski, R. S.

    1988-01-01

    Indole-3-acetic acid is oxidized to oxindole-3-acetic acid by Zea mays tissue extracts. Shoot, root, and endosperm tissues have enzyme activities of 1 to 10 picomoles per hour per milligram protein. The enzyme is heat labile, is soluble, and requires oxygen for activity. Cofactors of mixed function oxygenase, peroxidase, and intermolecular dioxygenase are not stimulatory to enzymic activity. A heat-stable, detergent-extractable component from corn enhances enzyme activity 6- to 10-fold. This is the first demonstration of the in vitro enzymic oxidation of indole-3-acetic acid to oxindole-3-acetic acid in higher plants.

  16. Oxidation of indole-3-acetic acid to oxindole-3-acetic acid by an enzyme preparation from Zea mays

    Science.gov (United States)

    Reinecke, D. M.; Bandurski, R. S.

    1988-01-01

    Indole-3-acetic acid is oxidized to oxindole-3-acetic acid by Zea mays tissue extracts. Shoot, root, and endosperm tissues have enzyme activities of 1 to 10 picomoles per hour per milligram protein. The enzyme is heat labile, is soluble, and requires oxygen for activity. Cofactors of mixed function oxygenase, peroxidase, and intermolecular dioxygenase are not stimulatory to enzymic activity. A heat-stable, detergent-extractable component from corn enhances enzyme activity 6- to 10-fold. This is the first demonstration of the in vitro enzymic oxidation of indole-3-acetic acid to oxindole-3-acetic acid in higher plants.

  17. Características y propiedades funcionales del maíz morado (Zea mays L.) var. subnigroviolaceo

    OpenAIRE

    Jhoseline Guillén-Sánchez; Sigry Mori-Arismendi; Luz María Paucar-Menacho

    2014-01-01

    Zea Mays L. variety purple (purple corn) is a plant native of America, which has the episperm seeds (grains) and the cobs (cob) in purple, which gives special characteristics to the pigments that have (between 1.5% and 6.0%), called anthocyanins, which belong to the group of flavonoids. Due to its high content of anthocyanins (cianin C3G-3-glucose as its main color) and phenolic compounds act as powerful natural antioxidant and anticancer, Further having functional properties due to these bio...

  18. Accumulation potentials of perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) in maize (Zea mays).

    Science.gov (United States)

    Krippner, Johanna; Falk, Sandy; Brunn, Hubertus; Georgii, Sebastian; Schubert, Sven; Stahl, Thorsten

    2015-04-15

    Uptake of perfluoroalkyl acids (PFAAs) by maize represents a potential source of exposure for humans, either directly or indirectly via feed for animals raised for human consumption. The aim of the following study was, therefore, to determine the accumulation potential of perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) in maize (Zea mays). Two different concentrations of PFAAs were applied as aqueous solution to the soil to attain target concentrations of 0.25 mg or 1.00 mg of PFAA per kg of soil. Maize was grown in pots, and after harvesting, PFAA concentrations were measured in the straw and kernels of maize. PFCA and PFSA concentrations of straw decreased significantly with increasing chain length. In maize kernels, only PFCAs with a chain length ≤ C8 as well as perfluorobutanesulfonic acid (PFBS) were detected. The highest soil-to-plant transfer for both straw and kernels was determined for short-chained PFCAs and PFSAs.

  19. Cytogenetics of monosomes in Zea mays. Progress report, October 1, 1975--January 31, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Weber, D. F.

    1976-10-01

    Monosomics lack a pairing partner in each meiotic cell and genes on an entire chromosome are present in the hemizygous condition. Monosomics for chromosomes 1, 2, 3, 4, 6, 7, 8, 9, and 10 in Zea mays were isolated utilizing a recently-discovered system. This is the first time that a series of this type has been recovered in any diploid organism. The monosomic plants are surprisingly vigorous, good cytological samples can be taken, and crosses made. We are isolating all possible monosomic types and characterizing them by studying the cytology of meiosis, the cytological behavior of monosomic chromosomes, the effect of monosomy and trisomy on intergenic and intragenic recombination, the frequency and types of spontaneous chromosomal aberrations arising in monosomics, the effect of monosomy on free amino acids, and the effect of monosomy on isozymes in leaves, the effect of trisomy on the lipid content, and the relative amounts of specific fatty acids in embryos.

  20. GERDAU S.A.: a empresa brasileira mais internacionalizada

    Directory of Open Access Journals (Sweden)

    EVA STAL

    2007-07-01

    Full Text Available Muitas empresas dos países em desenvolvimento não se consideram aptas a explorar outrosmercados devido à distância tecnológica entre as empresas globais e os seus padrões locais. Oartigo mostra que existe espaço para a inovação empresarial oriunda de países emdesenvolvimento, e ela é um dos principais fatores responsáveis pelo sucesso de suasempresas na conquista do mercado mundial. Descreve o processo de expansão internacionalda Gerdau S.A., que começou com exportações e evoluiu para a aquisição de empresassiderúrgicas na América Latina, América do Norte e Europa, num total de 32 usinas em 10países, sendo 21 no exterior, que empregam mais de 32 mil funcionários. Hoje, a empresapossui valor de mercado estimado em 10 bilhões de dólares e 111.000 acionistas. Analisa-sesua estratégia de internacionalização à luz das teorias econômicas, comportamentais eestratégicas e verifica-se que a trajetória internacional pode ser explicada por aspectoscaracterísticos de cada uma dessas teorias. Um traço importante na cultura da empresa é atransferência de seu modelo de negócios, estrutura, valores e tecnologia para as empresasadquiridas, sem deixar de considerar as necessárias adaptações às culturas locais.

  1. Revisitando a prospect theory: seriam os contadores mais racionais?

    Directory of Open Access Journals (Sweden)

    Daniel Jose Cardoso da Silva

    2012-05-01

    Full Text Available A Prospect Theory, teoria psicológica de tomada de decisões desenvolvida por Amos Tversky e Daniel Kahneman, apresenta que o ser humano é mais avesso ao risco em situação de ganhos do que de perdas, o que aqueles pesquisadores denominaram de efeito framing, residindo, portanto, nas heurísticas (crenças individuais o catalisador do fenômeno. Carvalho Junior (2009 afirma que o ser humano não é totalmente racional ao tomar decisão, notadamente em ambiente empresarial. Já Miranda et al. (2010 concluem que possuir conhecimentos em ciências contábeis ajudaria os agentes a tomarem melhores decisões de investimento, na presença de sunk costs. A partir disso, construiu-se o problema desta pesquisa: o aprendizado formal de contabilidade minimiza os vieses cognitivos provocados pelo efeito framing em decisões que envolvam risco financeiro? Foram analisadas as respostas de 222 indivíduos, solicitados a responder três questões, uma que sugeria risco financeiro (cenário de perda e uma livre de risco (cenário de ganho, e uma de autoavaliação do respondente. As formações acadêmicas, além de Contabilidade, se concentravam principalmente em Administração e Economia, com escolaridade variando de graduação em curso até possuidores do título de Doutor. Os dados coletados receberam tratamento estatístico com a utilização do software SPSS v. 16. Subsidiariamente à principal hipótese deste estudo, foram analisadas ainda outras três hipóteses, que avaliavam se o efeito framing poderia ser afetado, respectivamente, pelo gênero, pelo nível de escolaridade ou pela idade dos indivíduos pesquisados. Com base nos resultados obtidos, não foi possível em nenhum dos casos rejeitar a hipótese nula de cada uma das variáveis dummy o que induz à conclusão, considerando-se a amostra analisada, que nenhuma daquelas variáveis influenciaria de maneira significativamente estatística o comportamento daqueles respondentes pesquisados.

  2. Molecular evolution and expansion analysis of the NAC transcription factor in Zea mays.

    Directory of Open Access Journals (Sweden)

    Kai Fan

    Full Text Available NAC (NAM, ATAF1, 2 and CUC2 family is a plant-specific transcription factor and it controls various plant developmental processes. In the current study, 124 NAC members were identified in Zea mays and were phylogenetically clustered into 13 distinct subfamilies. The whole genome duplication (WGD, especially an additional WGD event, may lead to expanding ZmNAC members. Different subfamily has different expansion rate, and NAC subfamily preference was found during the expansion in maize. Moreover, the duplication events might occur after the divergence of the lineages of Z. mays and S. italica, and segmental duplication seemed to be the dominant pattern for the gene duplication in maize. Furthermore, the expansion of ZmNAC members may be also related to gain and loss of introns. Besides, the restriction of functional divergence was discovered after most of the gene duplication events. These results could provide novel insights into molecular evolution and expansion analysis of NAC family in maize, and advance the NAC researches in other plants, especially polyploid plants.

  3. Accumulation of Hydrocarbons by Maize (Zea mays L.) in Remediation of Soils Contaminated with Crude Oil.

    Science.gov (United States)

    Liao, Changjun; Xu, Wending; Lu, Guining; Liang, Xujun; Guo, Chuling; Yang, Chen; Dang, Zhi

    2015-01-01

    This study has investigated the use of screened maize for remediation of soil contaminated with crude oil. Pots experiment was carried out for 60 days by transplanting maize seedlings into spiked soils. The results showed that certain amount of crude oil in soil (≤2 147 mg·kg(-1)) could enhance the production of shoot biomass of maize. Higher concentration (6 373 mg·kg(-1)) did not significantly inhibit the growth of plant maize (including shoot and root). Analysis of plant shoot by GC-MS showed that low molecular weight polycyclic aromatic hydrocarbons (PAHs) were detected in maize tissues, but PAHs concentration in the plant did not increase with higher concentration of crude oil in soil. The reduction of total petroleum hydrocarbon in planted soil was up to 52.21-72.84%, while that of the corresponding controls was only 25.85-34.22% in two months. In addition, data from physiological and biochemical indexes demonstrated a favorable adaptability of maize to crude oil pollution stress. This study suggested that the use of maize (Zea mays L.) was a good choice for remediation of soil contaminated with petroleum within a certain range of concentrations.

  4. Exogenous melatonin improves corn (Zea mays L.) embryo proteome in seeds subjected to chilling stress.

    Science.gov (United States)

    Kołodziejczyk, Izabela; Dzitko, Katarzyna; Szewczyk, Rafał; Posmyk, Małgorzata M

    2016-04-01

    Melatonin (MEL; N-acetyl-5-methoxytryptamine) plays an important role in plant stress defense. Various plant species rich in this indoleamine have shown a higher capacity for stress tolerance. Moreover, it has great potential for plant biostimulation, is biodegradable and non-toxic for the environment. All this indicates that our concept of seed enrichment with exogenous MEL is justified. This work concerns the effects of corn (Zea mays L.) seed pre-sowing treatments supplemented with MEL. Non-treated seeds (nt), and those hydroprimed with water (H) or with MEL solutions 50 and 500 μM (HMel50, HMel500) were compared. Positive effects of seed priming are particularly apparent during germination under suboptimal conditions. The impact of MEL applied by priming on seed protein profiles during imbibition/germination at low temperature has not been investigated to date. In order to identify changes in the corn seed proteome after applying hydropriming techniques, purified protein extracts of chilling stressed seed embryos (14 days, 5°C) were separated by two-dimensional electrophoresis. Then proteome maps were graphically and statistically compared and selected protein spots were qualitatively analyzed using mass spectrometry techniques and identified. This study aimed to analyze the priming-induced changes in maize embryo proteome and at identifying priming-associated and MEL-associated proteins in maize seeds subjected to chilling. We attempt to explain how MEL expands plant capacity for stress tolerance.

  5. A multidrug resistance-associated protein involved in anthocyanin transport in Zea mays.

    Science.gov (United States)

    Goodman, Christopher Dean; Casati, Paula; Walbot, Virginia

    2004-07-01

    Anthocyanin biosynthesis is one of the most thoroughly studied enzymatic pathways in biology, but little is known about the molecular mechanisms of its final stage: the transport of the anthocyanin pigment into the vacuole. We have identified a multidrug resistance-associated protein (MRP), ZmMrp3, that is required for this transport process in maize (Zea mays). ZmMrp3 expression is controlled by the regulators of anthocyanin biosynthesis and mirrors the expression of other anthocyanin structural genes. Localization of ZmMRP3 in vivo shows its presence in the tonoplast, the site at which anthocyanin transport occurs. Mutants generated using antisense constructs have a distinct pigmentation phenotype in the adult plant that results from a mislocalization of the pigment as well as significant reduction in anthocyanin content, with no alteration in the anthocyanin species produced. Surprisingly, mutant plants did not show a phenotype in the aleurone. This appears to reflect the presence of a second, highly homologous gene, ZmMrp4, that is also coregulated with the anthocyanin pathway but is expressed exclusively in aleurone tissue. This description of a plant MRP with a role in the transport of a known endogenous substrate provides a new model system for examining the biological and biochemical mechanisms involved in the MRP-mediated transport of plant secondary metabolites.

  6. Corn (Zea mays growth in petroleum contaminated soil, remediated with orange (Citrus sinensis peel extract

    Directory of Open Access Journals (Sweden)

    Tomás Darío Marín Veláquez

    2016-09-01

    Full Text Available Soil pollution has a strong impact when oil activity takes place within a savanna ecosystem. Any oil spill affects agricultural soils. Biostimulation with orange peel extract (Citrus sinensis is an alternative for remediation of soil contaminated with crude oil and in this research the corn plant (Zea mays was used as a biomarker of contamination level of a savanna soil after their treatment. Three samples of savannah soil contaminated with oil light crude were treated with dissolutions 1, 3 and 5% of extract of orange peel in water at a dose of 150 mL per kg of soil treated. The content of oils and fats was measured every 7 days, up to 42 days. Corn seeds were planted in soil samples, their growth was measured every 5 days for a period of 35 consecutive days, comparing their growth with seeds planted in a soil sample without contamination. According to an analysis of rank contrast, the plant growth was statistically the same in all samples up to 20 days; from there, evident differences regarding the pattern were shown.

  7. Pinitol, a larval growth inhibitor for Heliothis zea in soybeans.

    Science.gov (United States)

    Dreyer, D L; Binder, R G; Chan, B G; Waiss, A C; Hartwig, E E; Beland, G L

    1979-09-15

    A search for insect growth inhibitors in methanol extracts of soybean leaves resulted in isolation of pinitol. Pinitol caused a 50% reduction in weight gain (ED50) of Heliothis zea larvae at about 0.7% when added to a synthetic diet. Although myo-inositol is a normal component of the insect diet, it also caused growth inhibition at higher concentrations; ED50 4%.

  8. 玉米苞叶中新黄酮类化合物的分离和鉴定%Isolation and Identification of Novel Flavonoids from the Bract of Zea mays L

    Institute of Scientific and Technical Information of China (English)

    张沐新; 刘银燕; 孙薇; 杨晓虹; 王广树

    2011-01-01

    从玉米(Zea maysL)苞叶乙醇提取物中分离得到了4个黄酮类化合物,采用UV,IR,MS,1D NMR和2D NMR方法对化合物的结构进行了鉴定,它们分别为苜蓿素(1)、苜蓿素-5-O-β-D-吡喃葡萄糖苷(2)、苜蓿素-7-O-β-D-吡喃葡萄糖苷(3)和苜蓿素-7-O-[β-D-呋喃芹糖基-(1-2)]β-D-吡喃葡萄糖苷(4).其中,化合物4为新化合物,化合物1~3为首次从该植物中分离得到.%Zea mays ( maize) , a member of the Poaceae, is the most economically important crop in China,about 24 million hectares of Zea mays has been cultivated each year in China, there is about 600 kg of the bract of Zea mays per hectare, and thus the resources of the bract of Zea mays is extremely rich. Although there are some pharmacological activity researches about radical scavenging activity against hydroxyl radical and superoxide anion radical, reducing blood lipid and inhibiting arteriosclerosis, the studies on phytochemical constituents of the bract of Zea mays have not been reported. In order to utilize the resources of the bract ofZea mays, we investigated the chemical constituents of the bract of Zea mays. The air-dried bract ol Zea mays was extracted with 95% ethanol at room temperature, the extract was subjected to Diaion AB-8 column chro-matography eluated with ethanol-H2O, and the eluate was further chromatographed on silica gel and Sephadex LH-20 columns repeatedly to yield 4 flavonoid compounds. Their structures were identified as tricin( 1) , tricin 5-0-β-D-glucopyranoside(2) , tricin 7-O-/M>-glucopyranoside(3) , tricin 7-0-[β-D-apifuranosyl( 1-+2) ]-β-D-glucopyranoside(4) by spectral analysis(UV, IR, MS and ID, 2D NMR) , respectively. Among them, compound 4 is a new flavonoid compound, compounds 1, 2 and 3 are firstly isolated from this plant.

  9. Cross-resistance to alpha-cypermethrin after xanthotoxin ingestion in Helicoverpa zea (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Li, X; Zangerl, A R; Schuler, M A; Berenbaum, M R

    2000-02-01

    Cytochrome P450 monooxygenases (P450) are membrane-bound hemoproteins that play important roles in conferring protection against both naturally occurring phytochemicals and synthetic organic insecticides. Despite the potential for common modes of detoxification, cross-resistance between phytochemicals and synthetic organic insecticides has rarely been documented. In this study, we examined the responses of a susceptible strain of corn earworm, Helicoverpa zea (Boddie), a polyphagous noctuid, to exposure by an allelochemical infrequently encountered in its host plants and by an insecticide widely used for control purposes. Within a single generation, survivors of xanthotoxin exposure displayed higher levels of tolerance to alpha-cypermethrin than did unexposed control larvae. The F1 offspring of xanthotoxin-exposed survivors also displayed higher alpha-cypermethrin tolerance than did offspring of unexposed control larvae, suggesting that increased alpha-cypermethrin tolerance after xanthotoxin exposure represents, at least in part, heritable resistance. Administration of piperonyl butoxide, a P450 synergist, demonstrated that resistance to both xanthotoxin and alpha-cypermethrin is P450-mediated. Alpha-cypermethrin-exposed survivors, however, failed to show superior growth on xanthotoxin diets. Assays with control larvae, larvae induced by both xanthotoxin and alpha-cypermethrin, and survivors of LD50 doses of both compounds indicated that H. zea midgut P450s are capable of metabolizing both xanthotoxin and alpha-cypermethrin. Metabolism of each compound is significantly inhibited by the presence of the other compound, suggesting that at least one form of P450 in H. zea midguts degrades both compounds and may constitute the biochemical basis for possible cross-resistance. Compared with control larvae, xanthotoxin- and alpha-cypermethrin-induced larvae displayed 2- to 4-fold higher P450-mediated metabolism of both compounds. However, xanthotoxin- and alpha

  10. Lead and cadmium in leaves of deciduous trees in Beijing, China: Development of a metal accumulation index (MAI)

    Energy Technology Data Exchange (ETDEWEB)

    Liu Yanju [Beijing Center for Physical and Chemical Analysis, Beijing 100089 (China) and Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China)]. E-mail: liuyanju@hotmail.com; Zhu Yongguan [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Ding Hui [Beijing Center for Physical and Chemical Analysis, Beijing 100089 (China)

    2007-01-15

    Lead and cadmium uptake was investigated for common deciduous street trees in Beijing in this study. Species having Cd accumulation included Populus tomentosa, Sophora japonica and Catalpa speciosa. P. tomentosa had the highest ratios between leaf and soil Cd (0.848), followed by S. japonica (0.536), C. speciosa (0.493), Paulownia tomentosa (0.453) and Juglans regia (0.415). Pb levels were high in leaves of C. speciosa, J. regia and Pa. tomentosa. S. japonica had the highest ratio between leaf Pb and soil Pb (0.146), followed by Pa. tomentosa (0.143), Ginko biloba (0.103) and C. speciosa (0.095). A predictive foliar metal accumulation index (MAI) was developed and C. speciosa was calculated to have the highest MAI value (53.8). This suggests that C. speciosa would be a good choice for planting in areas of Beijing where soil contamination with Cd and Pb may be a problem. - Catalpa speciosa had the highest MAI value.

  11. Reversibility of soil forming clay mineral reactions induced by plant - clay interactions

    Science.gov (United States)

    Barré, P.; Velde, B.

    2012-04-01

    Recent data based upon observations of field experiments and laboratory experiments suggest that changes in phyllosilicate mineralogy, as seen by X-ray diffraction analysis, which is induced by plant action can be reversed in relatively short periods of time. Changes from diagenetic or metamorphic mineral structures (illite and chlorite) to those found in soils (mixed layered minerals in the smectite, hydroxy-interlayer mineral and illites) observed in Delaware Bay salt marsh sediments in periods of tens of years and observed under different biologic (mycorhize) actions in coniferous forests in the soil environment can be found to be reversed under other natural conditions. Reversal of this process (chloritisation of smectitic minerals in soils) has been observed in natural situations over a period of just 14 years under sequoia gigantia. Formation of smectite minerals from illite (potassic mica-like minerals) has been observed to occur under intensive agriculture conditions over periods of 80 years or so under intensive zea mais production. Laboratory experiments using rye grass show that this same process can be accomplished to a somewhat lesser extent after one growing season. However experiments using alfalfa for 30 year growing periods show that much of the illite content of a soil can be reconstituted or even increased. Observations on experiments using zea mais under various fertilizer and mycorhize treatments indicate that within a single growing season potassium can be extracted from the clay (illite layers) but at the end of the season the potassium can be restored to the clay structures and more replaced that extracted. Hence it is clear that the change in clay mineralogy normally considered to be irreversible, illite to smectite or chlorite to smectite observed in soils, is a reversible process where plant systems control the soil chemistry and the soil mineralogy. The changes in clay mineralogy concern mostly the chemical composition of the interlayer

  12. Gerdau S.A.: a empresa brasileira mais internacionalizada

    Directory of Open Access Journals (Sweden)

    Eva Stal

    2008-01-01

    Full Text Available Many companies from developing countries do not consider themselves capable of exploring other markets due to the technological gap between them and global firms. This paper shows that there is an opportunity for innovation creation in these countries, and it is one of the main factors responsible for their success in the global market. It describes the process of international expansion of Gerdau, which started with exports and evolved to steel plants acquisitions in Latin and North America and Europe. Today the firm owns 32 mills in 10 countries, being 21 abroad, and 32.000 employees. Its international path is analyzed in the light of the internationalization theories – behavioral, economic and strategic – and each one explains part of the trajectory. An important feature of Gerdau’s culture is the transfer of its business model, structure, values and technology to the acquired firms, always considering the necessary adaptation to local culture.

  13. Measurement of the rates of oxindole-3-acetic acid turnover, and indole-3-acetic acid oxidation in Zea mays seedlings

    Science.gov (United States)

    Nonhebel, H. M.; Bandurski, R. S. (Principal Investigator)

    1986-01-01

    Oxindole-3-acetic acid is the principal catabolite of indole-3-acetic acid in Zea mays seedlings. In this paper measurements of the turnover of oxindole-3-acetic acid are presented and used to calculate the rate of indole-3-acetic acid oxidation. [3H]Oxindole-3-acetic acid was applied to the endosperm of Zea mays seedlings and allowed to equilibrate for 24 h before the start of the experiment. The subsequent decrease in its specific activity was used to calculate the turnover rate. The average half-life of oxindole-3-acetic acid in the shoots was found to be 30 h while that in the kernels had an average half-life of 35h. Using previously published values of the pool sizes of oxindole-3-acetic acid in shoots and kernels from seedlings of the same age and variety, and grown under the same conditions, the rate of indole-3-acetic acid oxidation was calculated to be 1.1 pmol plant-1 h-1 in the shoots and 7.1 pmol plant-1 h-1 in the kernels.

  14. Assessment of heavy metal accumulation and performance Of some physiological parameters in zea mays l. And Vic1a faba l. Grown on soil amended by sewage Sludge resulting from sewage water Treatment in the state of qatar

    OpenAIRE

    Mazen, A. M. A.

    1995-01-01

    Pot experiment was conducted to explore extent of concerns regarding agricultural use of sewage sludge for crop production in the state of Qatar. Extent of heavy metal accumulation and its subsequent impact on physiological performance in Zea mays and Viciafaba plants grown on sludge - amended soils was explored. Analysis revealed that all tested heavy metals were several times higher in pure sludge compared to pure garden soil. Plants grown in sludge -mixed soil accumulated large amounts of ...

  15. Métodos de analise dos danos da lagarta da espiga¹, em médias de gerações envolvendo IAC Maya e Zapalote Chico Method for analysis of damage of the corn earworm heliothis zea in generation means from IAC Maya and Zapalote Chico

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Marques Rezende

    1982-01-01

    Full Text Available O milho Zapalote Chico 2451 (ZC 2451, referido na literatura como a melhor fonte de resistência à lagarta da espiga, Heliothis zea (Boddie, 1850, e o IAC Maya XII foram observados em condições de campo, juntamente com as gerações F1, e F2 resultantes do cruzamento de ambos, bem como os respectivos retrocruzamentos da população F1, para cada um dos pais, a fim de estudar métodos de análises de dados obtidos através da escala de dano revista por WIDSTROM e, conseqüentemente, fornecer subsídios para trabalhos de estudo da herança da resistência envolvendo esse cruzamento. Para analisar os dados, dividiram-se as notas de dano em quatro classes distintas agrupadas duas a duas, zero mais 1 e > 2, e zero e > 1, e aplicou-se o método do quiquadrado (c2 para verificar qual divisão melhor se ajustava. Os resultados revelaram que o grupo das classes zero mais 1 e > 2 apresentou melhor uniformidade dos dados entre as repetições dentro de cada tratamento. A análise da variância para cada classe de dano, separadamente, apresentou valores de F altamente significativos para as classes zero e zero mais 1, enquanto para as classes > 1 e > 2, os mesmos não permitiram diferenciar os tratamentos. Entre as classes zero e zero mais 1, esta última revelou maior significância e melhor precisão dos dados. O milho ZC 2451, quando comparado com a variedade IAC Maya XII, exibiu boa resistência à lagarta da espiga nas condições de Campinas (SP, resistência essa relacionada com fatores de não preferência e/ou antibiose, devido ã maior porcentagem de espigas não danificadas do ZC 2451.The line Zapalote Chico 2451 (ZC 2451 resistant to the corn earworm, Heliothis zea, the commercial synthetic Brazilian variety IAC Maya XII, the F1 and F2 obtained with their cross, and the two back crosses between the F1 and both parents, were planted in the field in a randomized block with 10 replications. The earworm damage done to the ears was graded

  16. Evaluation of zinc accumulation, allocation, and tolerance in Zea mays L. seedlings: implication for zinc phytoextraction.

    Science.gov (United States)

    Bashmakov, Dmitry I; Lukatkin, Alexander S; Anjum, Naser A; Ahmad, Iqbal; Pereira, Eduarda

    2015-10-01

    This work investigated the accumulation, allocation, and impact of zinc (Zn; 1.0 μM-10 mM) in maize (Zea mays L.) seedlings under simulated laboratory conditions. Z. mays exhibited no significant change in its habitus (the physical characteristics of plants) up to 10-1000 μM of Zn (vs 5-10 mM Zn). Zn tolerance evaluation, based on the root test, indicated a high tolerance of Z. mays to both low and intermediate (or relatively high) concentrations of Zn, whereas this plant failed to tolerate 10 mM Zn and exhibited a 5-fold decrease in its Zn tolerance. Contingent to Zn treatment levels, Zn hampered the growth of axial organs and brought decreases in the leaf area, water regime, and biomass accumulation. Nevertheless, at elevated levels of Zn (10 mM), Zn(2+) was stored in the root cytoplasm and inhibited both axial organ growth and water regime. However, accumulation and allocation of Zn in Z. mays roots, studied herein employing X-ray fluorimeter and histochemical methods, were close to Zn accumulator plants. Overall, the study outcomes revealed Zn tolerance of Z. mays, and also implicate its potential role in Zn phytoextraction.

  17. Effect of different chelated zinc sources on the growth and yield of maize (Zea mays L.

    Directory of Open Access Journals (Sweden)

    M. Tahir

    2009-05-01

    Full Text Available A field study was conducted at Agronomic Research Area, University of Agriculture, Faisalabad during spring, 2007 to evaluate the effect of different chelated zinc sources on growth and yield of maize (Zea mays L.. Crop was sown on well prepared soil in 1st week of March, 2007. The experiment was laid out according to randomized complete block design. The treatments comprised of different chelated zinc sources: ZnSO4-DTPA, ZnSO4-Fulvate, ZnSO4-Lignosulphonate, ZnSO4-EDTA and ZnSO4-H2O along with control (no zinc, repeated three times. Results showed that number of cobs plant-1, grain rows cob-1 and oil contents did not differ significantly. However, differences among treatments for plant height at harvest (cm, leaf area plant-1 (cm2, stem diameter (cm, cob length (cm, cob diameter (cm, 100-grains weight (g, number of grains cob-1, grains weight cob-1(g, biological yield (tons ha-1, grain yield (tons ha-1 and protein contents (% were significantly higher. Moreover, results also revealed that ZnSO4-DPTA was found the most effective Zn chelated source among all the treatments. Rest of the chelating agents were not too impressive as they showed varied response for different variables. The result of this experiment suggest further experimentation to explore behaviour of Zn-DTPA with other macro and micro nutrients and to calculate cost benefit ratio for use ofZn chelated compounds.

  18. Identification of two frataxin isoforms in Zea mays: Structural and functional studies.

    Science.gov (United States)

    Buchensky, Celeste; Sánchez, Manuel; Carrillo, Martin; Palacios, Oscar; Capdevila, Mercè; Domínguez-Vera, Jose M; Busi, Maria V; Atrian, Sílvia; Pagani, Maria A; Gomez-Casati, Diego F

    2017-09-01

    Frataxin is a ubiquitous protein that plays a role in Fe-S cluster biosynthesis and iron and heme metabolism, although its molecular functions are not entirely clear. In non-photosynthetic eukaryotes, frataxin is encoded by a single gene, and the protein localizes to mitochondria. Here we report the presence of two functional frataxin isoforms in Zea mays, ZmFH-1 and ZmFH-2. We confirmed our previous findings regarding plant frataxins: both proteins have dual localization in mitochondria and chloroplasts. Physiological, biochemical and biophysical studies show some differences in the expression pattern, protection against oxidants and in the aggregation state of both isoforms, suggesting that the two frataxin homologs would play similar but not identical roles in plant cell metabolism. In addition, two specific features of plant frataxins were evidenced: their ability to form dimers and their tendency to undergo conformational change under oxygen exposure. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  19. A seed mixture increases dominance of resistance to Bt cotton in Helicoverpa zea.

    Science.gov (United States)

    Brévault, Thierry; Tabashnik, Bruce E; Carrière, Yves

    2015-05-07

    Widely grown transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt) can benefit agriculture, but adaptation by pests threatens their continued success. Refuges of host plants that do not make Bt toxins can promote survival of susceptible insects and delay evolution of resistance, particularly if resistance is inherited as a recessive trait. However, data have been lacking to compare the dominance of resistance when Bt and non-Bt seeds are planted in random mixtures versus separate blocks. Here we report results from greenhouse experiments with transgenic cotton producing Bt toxin Cry1Ac and the bollworm, Helicoverpa zea, showing that the dominance of resistance was significantly higher in a seed mixture relative to a block of Bt cotton. The proportion of larvae on non-Bt cotton plants in the seed mixture was also significantly higher than expected under the null hypothesis of random distribution. In simulations based on observed survival, resistance evolved 2- to 4.5-fold faster in the seed mixture relative to separate blocks of Bt and non-Bt cotton. These findings support previous modelling results indicating that block refuges may be more effective than seed mixtures for delaying resistance in pests with mobile larvae and inherently low susceptibility to the toxins in Bt crops.

  20. Differential expression of superoxide dismutase genes in aphid-stressed maize (Zea mays L.) seedlings.

    Science.gov (United States)

    Sytykiewicz, Hubert

    2014-01-01

    The aim of this study was to compare the expression patterns of superoxide dismutase genes (sod2, sod3.4, sod9 and sodB) in seedling leaves of the Zea mays L. Tasty Sweet (susceptible) and Ambrozja (relatively resistant) cultivars infested with one of two hemipteran species, namely monophagous Sitobion avenae F. (grain aphid) or oligophagous Rhopalosiphum padi L. (bird cherry-oat aphid). Secondarily, aphid-elicited alternations in the antioxidative capacity towards DPPH (1,1-diphenyl-2-picrylhydrazyl) radical in insect-stressed plants were evaluated. Comprehensive comparison of expression profiles of the four sod genes showed that both insect species evoked significant upregulation of three genes sod2, sod3.4 and sod9). However, aphid infestation affected non-significant fluctuations in expression of sodB gene in seedlings of both maize genotypes. The highest levels of transcript accumulation occurred at 8 h (sod2 and sod3.4) or 24 h (sod9) post-infestation, and aphid-induced changes in the expression of sod genes were more dramatic in the Ambrozja cultivar than in the Tasty Sweet variety. Furthermore, bird cherry-oat aphid colonization had a more substantial impact on levels of DPPH radical scavenging activity in infested host seedlings than grain aphid colonization. Additionally, Ambrozja plants infested by either hemipteran species showed markedly lower antioxidative capacity compared with attacked Tasty Sweet plants.

  1. Expression profiling of selected glutathione transferase genes in Zea mays (L.) seedlings infested with cereal aphids.

    Science.gov (United States)

    Sytykiewicz, Hubert; Chrzanowski, Grzegorz; Czerniewicz, Paweł; Sprawka, Iwona; Łukasik, Iwona; Goławska, Sylwia; Sempruch, Cezary

    2014-01-01

    The purpose of this report was to evaluate the expression patterns of selected glutathione transferase genes (gst1, gst18, gst23 and gst24) in the tissues of two maize (Zea mays L.) varieties (relatively resistant Ambrozja and susceptible Tasty Sweet) that were colonized with oligophagous bird cherry-oat aphid (Rhopalosiphum padi L.) or monophagous grain aphid (Sitobion avenae L.). Simultaneously, insect-triggered generation of superoxide anion radicals (O2•-) in infested Z. mays plants was monitored. Quantified parameters were measured at 1, 2, 4, 8, 24, 48 and 72 h post-initial aphid infestation (hpi) in relation to the non-infested control seedlings. Significant increases in gst transcript amounts were recorded in aphid-stressed plants in comparison to the control seedlings. Maximal enhancement in the expression of the gst genes in aphid-attacked maize plants was found at 8 hpi (gst23) or 24 hpi (gst1, gst18 and gst24) compared to the control. Investigated Z. mays cultivars formed excessive superoxide anion radicals in response to insect treatments, and the highest overproduction of O2•- was noted 4 or 8 h after infestation, depending on the aphid treatment and maize genotype. Importantly, the Ambrozja variety could be characterized as having more profound increments in the levels of gst transcript abundance and O2•- generation in comparison with the Tasty Sweet genotype.

  2. Effect of biochar on reclaimed tidal land soil properties and maize (Zea mays L.) response.

    Science.gov (United States)

    Kim, Hyuck-Soo; Kim, Kwon-Rae; Yang, Jae E; Ok, Yong Sik; Owens, Gary; Nehls, Thomas; Wessolek, Gerd; Kim, Kye-Hoon

    2016-01-01

    Reclaimed tidal land soil (RTLS) often contains high levels of soluble salts and exchangeable Na that can adversely affect plant growth. The current study examined the effect of biochar on the physicochemical properties of RTLS and subsequently the influence on plant growth performance. Rice hull derived biochar (BC) was applied to RTLS at three different rates (1%, 2%, and 5% (w/w)) and maize (Zea mays L.) subsequently cultivated for 6weeks. While maize was cultivated, 0.1% NaCl solution was supplied from the bottom of the pots to simulate the natural RTLS conditions. Biochar induced changes in soil properties were evaluated by the water stable aggregate (WSA) percentage, exchangeable sodium percentage (ESP), soil organic carbon contents, cation exchange capacity, and exchangeable cations. Plant response was measured by growth rate, nutrient contents, and antioxidant enzyme activity of ascorbate peroxidase (APX) and glutathione reductase (GR). Application of rice hull derived biochar increased the soil organic carbon content and the percentage of WSA by 36-69%, while decreasing the ESP. The highest dry weight maize yield was observed from soil which received 5% BC (w/w), which was attributed to increased stability of water-stable aggregates and elevated levels of phosphate in BC incorporated soils. Moreover, increased potassium, sourced from the BC, induced mitigation of Na uptake by maize and consequently, reduced the impact of salt stress as evidenced by overall declines in the antioxidant activities of APX and GR.

  3. Differential expression of superoxide dismutase genes in aphid-stressed maize (Zea mays L. seedlings.

    Directory of Open Access Journals (Sweden)

    Hubert Sytykiewicz

    Full Text Available The aim of this study was to compare the expression patterns of superoxide dismutase genes (sod2, sod3.4, sod9 and sodB in seedling leaves of the Zea mays L. Tasty Sweet (susceptible and Ambrozja (relatively resistant cultivars infested with one of two hemipteran species, namely monophagous Sitobion avenae F. (grain aphid or oligophagous Rhopalosiphum padi L. (bird cherry-oat aphid. Secondarily, aphid-elicited alternations in the antioxidative capacity towards DPPH (1,1-diphenyl-2-picrylhydrazyl radical in insect-stressed plants were evaluated. Comprehensive comparison of expression profiles of the four sod genes showed that both insect species evoked significant upregulation of three genes sod2, sod3.4 and sod9. However, aphid infestation affected non-significant fluctuations in expression of sodB gene in seedlings of both maize genotypes. The highest levels of transcript accumulation occurred at 8 h (sod2 and sod3.4 or 24 h (sod9 post-infestation, and aphid-induced changes in the expression of sod genes were more dramatic in the Ambrozja cultivar than in the Tasty Sweet variety. Furthermore, bird cherry-oat aphid colonization had a more substantial impact on levels of DPPH radical scavenging activity in infested host seedlings than grain aphid colonization. Additionally, Ambrozja plants infested by either hemipteran species showed markedly lower antioxidative capacity compared with attacked Tasty Sweet plants.

  4. Open Field Study of Some Zea mays Hybrids, Lipid Compounds and Fumonisins Accumulation

    Directory of Open Access Journals (Sweden)

    Paola Giorni

    2015-09-01

    Full Text Available Lipid molecules are increasingly recognized as signals exchanged by organisms interacting in pathogenic and/or symbiotic ways. Some classes of lipids actively determine the fate of the interactions. Host cuticle/cell wall/membrane components such as sphingolipids and oxylipins may contribute to determining the fate of host–pathogen interactions. In the present field study, we considered the relationship between specific sphingolipids and oxylipins of different hybrids of Zea mays and fumonisin by F. verticillioides, sampling ears at different growth stages from early dough to fully ripe. The amount of total and free fumonisin differed significantly between hybrids and increased significantly with maize ripening. Oxylipins and phytoceramides changed significantly within the hybrids and decreased with kernel maturation, starting from physiological maturity. Although the correlation between fumonisin accumulation and plant lipid profile is certain, the data collected so far cannot define a cause-effect relationship but open up new perspectives. Therefore, the question—“Does fumonisin alter plant lipidome or does plant lipidome modulate fumonisin accumulation?”—is still open.

  5. Azospirillum brasilense does not affect population structure of specific rhizobacterial communities of inoculated maize (Zea mays).

    Science.gov (United States)

    Herschkovitz, Yoav; Lerner, Anat; Davidov, Yaacov; Okon, Yaacov; Jurkevitch, Edouard

    2005-11-01

    Positive response of plant species to plant growth-promoting rhizobacteria have led to an increased interest in their use as bacterial inoculants. However, the introduction of exogenous bacteria into natural ecosystems may perturb bacterial populations within the microbial community and lead to the disruption of indigenous populations performing key functional roles. In this study the effect of Azospirillum brasilense inoculation on maize (Zea mays) rhizosphere Actinobacteria, Bacteroidetes, alpha-Proteobacteria, Pseudomonas and Bdellovibrio spp. was assessed using a polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) approach in conjunction with group-specific primers. The DGGE fingerprints analysis revealed that the introduction of A. brasilense did not alter or disrupt the microbial system at the group-specific level. However, some communities such as the alpha-Proteobacteria and Bdellovibrio were influenced by plant age while the other bacterial groups remained unaffected. Based on these as well as previous data, it can be inferred that inoculation with A. brasilense does not perturb the natural bacterial populations investigated.

  6. Phytotoxicity assay of diesel fuel-spiked substrates remediated with Pleurotus tuberregium using Zea mays

    Directory of Open Access Journals (Sweden)

    E M Ogbo

    2010-06-01

    Full Text Available Summary: The remediation of soil contaminated with petroleum based compounds by white rot fungi is well documented.  In this study the ability of diesel fuel contaminated soils treated with the fungus Pleurotus tuber-regium to support plant growth was tested.  Pleurotus tuber-regium was grown in different levels (2.50, 5.00, 10.00% and control- no fungus for each level of contamination of diesel fuel contaminated soil and sawdust. The removal of petroleum hydrocarbons was highest in the 5.00% level of contamination where 55.53% of the petroleum hydrocarbons were removed. The least reduction in hydrocarbons was in the 10.00% level of contamination where only 35.53% of the hydrocarbons were removed. After the remediation the toxicity of the soils were tested by growing Zea mays in the treated soils. There was reduction in the toxicity of the soils treated with Pleurotus tuber-regium. Germination of the seeds of the test plant in treated 2.50 and 5.00% diesel fuel contaminated substrates was higher than that in the control. Germination of seeds in the 10.00% diesel fuel contaminated substrates was less than that in the control. The continued growth of the plant in the treated soils however showed no significant difference between them and the control using leaf area, plant height, fresh weight, dry weight and root length indices. The formation of lateral roots was however adversely affected in the treated 10.00% contaminated soil only substrate. The fungus was able to reduce the toxicity of diesel fuel contaminated substrates when compared with control in which there was no remediation. Industrial relevance: Nigeria is an oil producing country with heavy or high reliance on diesel fuel for use in cars and electric power generating sets. The transportation of diesel fuel is by tankers and pipelines. There have been cases of spills which has adverse effect on the environment. The study aims to solve the process of amelioration of the environment

  7. MaisTer® Power: a Terbuthylazin free new solution to control monocotyledonous and dicotyledonous weeds in maize.

    Directory of Open Access Journals (Sweden)

    Wegener, Martin

    2014-02-01

    Full Text Available MaisTer® power is a combination of the well-known active ingredients Foramsulfuron (31,5 g/L, Iodosulfuron (1,04 g/L and the new developed ai Thiencarbazone-methyl (10,0 g/L and the new safener Cyprosulfamide (15,0 g/L. All three active ingredients belong to the group of the ALS inhibitors. The product can be applied with a dose rate of 1,5 L/ha or 1,0 L/ha. Foramsulfuron and Iodosulfuron will be taken up via the leaves of the plants whereas Thiencarbazone-methyl can penetrate the plants via the roots and the leaves. By using a dose rate of 1,5 L/ha a very good residual activity against new flushes of grass or broadleaf weeds will be observed. All relevant grass and broadleaf weeds in maize will be controlled after the application of MaisTer power including Polygonum species. If a dose rate of 1,0 L/ha is used it could make sense to add a tank mix partner like Aspect to complete the spectrum against some weeds like Chenopodium album or Polygonum convolvulus.

  8. Buried Alive! An Investigation of Plant Dormancy

    Science.gov (United States)

    Allen, Ashley J.; Balschweid, Mark; Hammond, Paul; Henderson, Brian; Johnson, Peggy A.; Kite, Abigayle; Martin, Stephanie

    2004-01-01

    In this investigation, pairs of upper elementary students test germination percentage using seeds of Indian corn ("Zea mays"), scarlet runner beans ("Phaseolus coccineus"), and the prairie cup-plant ("Silphium perfoliatum") grown on rolled, damp paper towels. The pairs compare seeds that have been stratified, a simulation of overwintering and…

  9. Towards efficient photosynthesis: overexpression of Zea mays phosphoenolpyruvate carboxylase in Arabidopsis thaliana.

    Science.gov (United States)

    Kandoi, Deepika; Mohanty, Sasmita; Govindjee; Tripathy, Baishnab C

    2016-12-01

    Plants with C4 photosynthesis are efficient in carbon assimilation and have an advantage over C3 photosynthesis. In C4 photosynthesis, the primary CO2 fixation is catalyzed by phosphoenolpyruvate carboxylase (PEPC). Here, we show that overexpression of Zea mays PEPC cDNA, under the control of (35)S promoter, in Arabidopsis thaliana resulted in ~7-10 fold higher protein abundance and ~7-10 fold increase in PEPC activity in the transgenic lines than that in the vector control. We suggest that overexpression of PEPC played an anaplerotic role to increase the supply of 4-carbon carboxylic acids, which provided carbon skeletons for increased amino acid and protein synthesis. Higher protein content must have been responsible for increased metabolic processes including chlorophyll biosynthesis, photosynthesis, and respiration. Consequently, the PEPC-overexpressed transgenic plants had higher chlorophyll content, enhanced electron transport rate (ETR), lower non-photochemical quenching (NPQ) of chlorophyll a fluorescence, and a higher performance index (PI) than the vector control. Consistent with these observations, the rate of CO2 assimilation, the starch content, and the dry weight of PEPC-overexpressed plants increased by 14-18 %, 10-18 %, and 6.5-16 %, respectively. Significantly, transgenics were tolerant to salt stress as they had increased ability to synthesize amino acids, including the osmolyte proline. NaCl (150 mM)-treated transgenic plants had higher variable to maximum Chl a fluorescence (F v/F m) ratio, higher PI, higher ETR, and lower NPQ than the salt-treated vector controls. These results suggest that expression of C4 photosynthesis enzyme(s) in a C3 plant can improve its photosynthetic capacity with enhanced tolerance to salinity stress.

  10. β-aminobutyric acid mediated drought stress alleviation in maize (Zea mays L.).

    Science.gov (United States)

    Shaw, Arun K; Bhardwaj, Pardeep K; Ghosh, Supriya; Roy, Sankhajit; Saha, Suman; Sherpa, Ang R; Saha, Samir K; Hossain, Zahed

    2016-02-01

    The present study highlights the role of β-aminobutyric acid (BABA) in alleviating drought stress effects in maize (Zea mays L.). Chemical priming was imposed by pretreating 1-week-old plants with 600 μM BABA prior to applying drought stress. Specific activities of key antioxidant enzymes and metabolites (ascorbate and glutathione) levels of ascorbate-glutathione cycle were studied to unravel the priming-induced modulation of plant defense system. Furthermore, changes in endogenous ABA and JA concentrations as well as mRNA expressions of key genes involved in their respective biosynthesis pathways were monitored in BABA-primed (BABA+) and non-primed (BABA-) leaves of drought-challenged plants to better understand the mechanistic insights into the BABA-induced hormonal regulation of plant response to water-deficit stress. Accelerated stomatal closure, high relative water content, and less membrane damage were observed in BABA-primed leaves under water-deficit condition. Elevated APX and SOD activity in non-primed leaves found to be insufficient to scavenge all H2O2 and O2 (·-) resulting in oxidative burst as evident after histochemical staining with NBT and DAB. A higher proline accumulation in non-primed leaves also does not give much protection against drought stress. Increased GR activity supported with the enhanced mRNA and protein expressions might help the BABA-primed plants to maintain a high GSH pool essential for sustaining balanced redox status to counter drought-induced oxidative stress damages. Hormonal analysis suggests that in maize, BABA-potentiated drought tolerance is primarily mediated through JA-dependent pathway by the activation of antioxidant defense systems while ABA biosynthesis pathway also plays an important role in fine-tuning of drought stress response.

  11. Optical Reflectance and Fluorescence for Detecting Nitrogen Needs in Zea mays L.

    Science.gov (United States)

    McMurtrey, J. E.; Middleton, E. M.; Corp. L. A.; Campbell, P. K. Entcheva; Butcher, L. M.; Daughtry, C. S. T.

    2003-01-01

    Nitrogen (N) status in field grown corn (Zea mays L.) was assessed using spectral techniques. Passive reflectance remote sensing and, both passive and active fluorescence sensing methods were investigated. Reflectance and fluorescence methods are reported to detect changes in the primary plant pigments (chlorophylls a and b; carotenoids) in higher plant species. As a general rule, foliar chlorophyll a (Chl a) and chlorophyll b (Chl b) usually exist in approx.3:l ratio. In plants under stress, Chl b content is affected before Chl a reductions occur. For reflectance, a version of the chlorophyll absorption in reflectance index (CARI) method was tested with narrow bands from the Airborne Imaging Spectroradiometer for Applications (ASIA). CARI minimizes the effects of soil background on the signal from green canopies. A modified CARI (MCARI) was used to track total Chl a levels in the red dip of the spectrum from the corn canopy. A second MCARI was used to track the auxiliary plant pigments (Chl b and the carotenoids) in the yellow/orange/red edge part of the reflectance spectrum. The difference between these two MCARI indices detected variations in N levels across the field plot canopies using ASIA data. At the leaf level, ratios of fluorescence emissions in the blue, green, red and far-red wavelengths sensed responses that were associated with the plant pigments, and were indicative of energy transfer in the photosynthetic process. N stressed corn stands could be distinguish from those with optimally applied N with fluorescence emission spectra obtained from individual corn leaves. Both reflectance and fluorescence methods are sensitive in detecting corn N needs and may be especially powerful in monitoring crop conditions if both types of information can be combined.

  12. Parasitic and bacterial contamination in collards using effluent from treated domestic wastewater in Chiang Mai, Thailand.

    Science.gov (United States)

    Keawvichit, R; Wongworapat, K; Putsyainant, P; Silprasert, A; Karnchanawong, S

    2001-01-01

    Thailand often has inadequate water supply for agriculture during the dry season. The reuse of treated wastewater treatment plants could solve this problem. Treatment of domestic wastewater of Chiang Mai municipality by the aerated lagoon system (AL) releases more than 25,000 m3 of treated water everyday. The reuse of wastewater in agriculture is an efficient use of water, especially in tropical countries or in drought zones. The objective of this study is to demonstrate the possibility of using treated wastewater in growing edible vegetables, ie collards (kale), without pathogenic parasite and bacterial contamination. Collards (Brassica oleracea var acephala) were grown using either the treated wastewater from the aerated lagoon system (AL) or ground water (GW). Three cropping times were scheduled in February, May and July, 2000. Samples of water from AL system and GW were taken two times per month (the consecutive weeks) from February to July and examined for bacteria and parasites. Irrigation water (IW) that was normally used in agriculture was also collected, at the same time of the AL and GW collection, for bacteria and parasite investigation. A soil sample was taken before and after each crop for parasite examination. Collards were also collected at the end of the crop for parasite investigation. The results showed that GW seems to be a clean water since no pathogenic bacteria were found although small amount of Escherichia coli was noted in May. For AL and IW, similar number and types of bacteria were found. They were Aeromonas sobria, A. hydrophila, E. coli, Citrobacter freundii, Pseudomonas aeruginosa, non-pathogenic type of Vibrio cholerae. The small number of Salmonella enteritidis gr E was found in AL in April. After investigating 12 samples in 6 months of each kind of water, ie GW, Al, and IW, no parasite was found. Only unidentified free living nematodes were found in IW but those parasites are non pathogenic. A small number of unidentified free

  13. Enhanced formation of aerenchyma and induction of a barrier to radial oxygen loss in adventitious roots of Zea nicaraguensis contribute to its waterlogging tolerance as compared with maize (Zea mays ssp. mays).

    Science.gov (United States)

    Abiko, Tomomi; Kotula, Lukasz; Shiono, Katsuhiro; Malik, Al Imran; Colmer, Timothy David; Nakazono, Mikio

    2012-09-01

    Enhancement of oxygen transport from shoot to root tip by the formation of aerenchyma and also a barrier to radial oxygen loss (ROL) in roots is common in waterlogging-tolerant plants. Zea nicaraguensis (teosinte), a wild relative of maize (Zea mays ssp. mays), grows in waterlogged soils. We investigated the formation of aerenchyma and ROL barrier induction in roots of Z. nicaraguensis, in comparison with roots of maize (inbred line Mi29), in a pot soil system and in hydroponics. Furthermore, depositions of suberin in the exodermis/hypodermis and lignin in the epidermis of adventitious roots of Z. nicaraguensis and maize grown in aerated or stagnant deoxygenated nutrient solution were studied. Growth of maize was more adversely affected by low oxygen in the root zone (waterlogged soil or stagnant deoxygenated nutrient solution) compared with Z. nicaraguensis. In stagnant deoxygenated solution, Z. nicaraguensis was superior to maize in transporting oxygen from shoot base to root tip due to formation of larger aerenchyma and a stronger barrier to ROL in adventitious roots. The relationships between the ROL barrier formation and suberin and lignin depositions in roots are discussed. The ROL barrier, in addition to aerenchyma, would contribute to the waterlogging tolerance of Z. nicaraguensis.

  14. PATOGENICIDAD BACTERIANA EN MAÍZ (ZEA MAYS)

    OpenAIRE

    Rocío Pérez-y-Terrón; Julio César Carmona Díaz; Jorge Alejandro Cebada Ruíz; José Antonio Munive Hernández

    2012-01-01

    El maíz es un grano de consumo mundial para alimento tanto humano como animal. México se encuentra en el séptimo lugar de la producción, China y Estados Unidos son los principales consumidores. Zea mays pertenece a la familia de las gramíneas y tiene producción anual. La planta se puede ver afectada por plagas principalmente de diferentes especies de insectos. Puede también desarrollar enfermedad debida a hongos y virus, así como a bacterias patogénicas. Dentro de estas la causada por organis...

  15. Flutuação Populacional e Parasitismo de Ovos de Spodoptera frugiperda e Helicoverpa zea em milho pulverizado com extratos vegetais e Metarhizium anisopliae

    Directory of Open Access Journals (Sweden)

    Jaqueline Ramos de Freitas

    2010-10-01

    Full Text Available We evaluated the effect of plant extracts and Metarhizium anisopliae on population and parasitism of eggs of Spodoptera frugiperda and Helicoverpa zea in corn planted at two spacings. The research was conducted at the Agricultural School "Assis Chateaubriand" in Laguna Seca, PB, and Laborat6rio of Entomology at the Center for Integrated Pest Management / UEPB in Campina Grande-PB. Corn was planted in an area of 500m2, in spacing: (I 0,8 m x 0,4 m, and (II 0,4 m x 0,4 m, with one or two plants per hole, respectively. The treatments consisted of: 1 water as a control, 2 M. anisopliae (100 g 10 L-1 water, 3 Extract of Momordica charantia (50 ml L-1 water, 4 M. anisopliae (10 g L-1 water + water extract of M. charantia (50 ml L-1 water, 5 M. anisopliae (10 g L-1 water + cassava (Manihot esculenta Crantz (50 ml L-1 water. According to the results, no significant difference between treatments to control spacing I S. frugiperda egg, which was due, probably, late spraying, when 100% of the plants were attacked. The treatments also not efficient to control H zea eggs, recommending further studies to determine the concentration and dosage most appropriate for controlling these pests.

  16. Cytogenetics of monosomes in Zea mays. Progress report, May 16, 1979-May 15, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Weber, D. F.

    1980-02-01

    Monosomics lack a pairing partner in each meiotic cell, and genes on an entire chromosome are present in the hemizygous condition. Monosomics for chromosomes 1, 2, 3, 4, 6, 7, 8, 9, and 10 in Zea mays have been isolated. This is the only series of this type that has been recovered in any diploid organism. The monosomic plants are vigorous, good cytological samples can be taken, and crosses can be made. All possible monosomic types are being isolated and characterized by studying: (1) the cytology of meiosis; (2) the cytological behavior of univalent chromosomes; (3) the effect of monosomy and trisomy on intergenic and intragenic recombination; (4) the frequency and types of spontaneous chromosomal aberrations arising in monosomics; (5) the effect of aneuploidy on the relative amounts of specific fatty acids in embryos; (6) monosomic mutational mapping; and (7) metabolic profile analysis of monosomics. Systems in maize to detect the environmental and genetic induction of non-disjunction are also being developed. By comparing a monosomic with its disomic siblings, one compares one and two copies of all genes on an entire chromosome. If a gene expressing dosage effects resides on a specific chromosome, a difference will be found between a plant monosomic for that chromosome and its diploid siblings. Genetic factors that control the meiotic process, genetic recombination, lipid biosynthesis, and the free amino acid pool have been discovered.

  17. Protein Changes in Response to Pyrene Stress in Maize (Zea mays L.) Leaves

    Institute of Scientific and Technical Information of China (English)

    Sheng-You Xu; Ying-Xu Chen; Wei-Xiang Wu; Shao-Jian Zheng; Sheng-Guo Xue; Shi-Ying Yang; Yi-Jin Peng

    2007-01-01

    Phytoremediation is a relatively new approach to remove polycyclic aromatic hydrocarbons (PAHs) from the environment. When plants are grown under pyrene treatment, they respond by synthesizing a set of protective proteins. To learn more about protein changes in response to pyrene treatment, we extracted total proteins from the leaves of maize (Zea mays L.) 1 week after pyrene treatment. The proteins extracted were separated with twodimensional gel electrophoresis. In total, approximately 54 protein spots were found by comparing gels from treated and control groups. According to the isoelectric point, molecular weight, and abundance of these protein spots, 20 pyrene-induced proteins were found to have changed abundance. Of these, 15 protein spots were increased and five protein spots were newly appeared in pyrene-treated plant leaves. Six model upregulated protein spots of different molecular weights were excised from the gels and subjected to trypsin digestion followed by peptide separation using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Peptlde masses were used to search the matrix-science database for protein identification. Two of the proteins were identified on the basis of the homology of their peptide profiles with existing protein sequences as pyruvate orthophosphate dikinase and the rlbulose-1,5-bisphosphate carboxylase/oxygenase large subunit. These proteins are involved in the regulation of carbohydrate and energy metabolism. The present study gives new insights into the pyrene stress response in maize leaves and demonstrates the power of the proteomlc approach in phytoremediation of PAHs.

  18. Compositional equivalency of Cry1F corn event TC6275 and conventional corn (Zea mays L.).

    Science.gov (United States)

    Herman, Rod A; Phillips, Amy M; Collins, Randy A; Tagliani, Laura A; Claussen, Fred A; Graham, Christopher D; Bickers, Brenda L; Harris, Travis A; Prochaska, Lee M

    2004-05-01

    Maize (Zea mays L.) plants have been transformed to express a Cry1F insecticidal crystal protein originally isolated from Bacillus thuringiensis Berliner. This protein controls lepidopteran pests of maize, including the European corn borer, Ostrinia nubilalis (Hübner). As part of the safety assessment for crops containing transgenes, a compositional analysis of the food and feed is conducted. This analysis is designed to detect unintended changes in the nutrient and antinutrient content of the raw commodities produced by the crop due to the insertion of the genes into the genomic DNA of the plant (pleotropic effects). Samples of transgenic and nontransgenic maize forage and grain were collected from six field sites located in the U.S. and Canada. Forage samples were analyzed for proximates and minerals, and grain was further analyzed for fatty acids, amino acids, vitamins, secondary metabolites, and antinutrients. Results demonstrated that maize expressing the Cry1F protein was equivalent to nontransgenic maize with respect to these important components. Comparison of the variability within the nontransgenic and transgenic hybrid, as compared to composition values reported in the literature, suggest that factors other than transgenes may contribute more substantially to the composition of crops.

  19. Physiological Responses of Zea mays Seedlings to Interactions Between Cadmium and Salinity

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The effects of 0, 2.5, 5.0, and 10.0 μmol/L Cd2+ (Cd(NO3)2·4H2O) and 0, 10, 25, 50, and 100 mmol/L NaCl on growth,photosynthesis and the content of some ions in maize (Zea mays L.) were investigated in the present study. With increasing concentrations of Cd2+ or NaCl alone in Hoagland nutrient solution, the chlorophylls and starch content decreased. Combination treatment with salinity and cadmium increased the negative effects observed following the two stresses alone. Plants exhibiting growth retardation in response to one mild stress factor (25-50 mmol/L NaCl) became more tolerant to the other stress factor (Cd). The exposure of plants to cadmium caused a partial reversal of the effects of salinity. Root and shoot growth, ion accumulation and levels of photosynthetic pigments were improved at moderate concentrations of the two stress factors imposed jointly.

  20. Overexpression of Arabidopsis molybdenum cofactor sulfurase gene confers drought tolerance in maize (Zea mays L.).

    Science.gov (United States)

    Lu, Yao; Li, Yajun; Zhang, Jiachang; Xiao, Yitao; Yue, Yuesen; Duan, Liusheng; Zhang, Mingcai; Li, Zhaohu

    2013-01-01

    Abscisic acid (ABA) is a key component of the signaling system that integrates plant adaptive responses to abiotic stress. Overexpression of Arabidopsis molybdenum cofactor sulfurase gene (LOS5) in maize markedly enhanced the expression of ZmAO and aldehyde oxidase (AO) activity, leading to ABA accumulation and increased drought tolerance. Transgenic maize (Zea mays L.) exhibited the expected reductions in stomatal aperture, which led to decreased water loss and maintenance of higher relative water content (RWC) and leaf water potential. Also, transgenic maize subjected to drought treatment exhibited lower leaf wilting, electrolyte leakage, malondialdehyde (MDA) and H(2)O(2) content, and higher activities of antioxidative enzymes and proline content compared to wild-type (WT) maize. Moreover, overexpression of LOS5 enhanced the expression of stress-regulated genes such as Rad 17, NCED1, CAT1, and ZmP5CS1 under drought stress conditions, and increased root system development and biomass yield after re-watering. The increased drought tolerance in transgenic plants was associated with ABA accumulation via activated AO and expression of stress-related gene via ABA induction, which sequentially induced a set of favorable stress-related physiological and biochemical responses.

  1. Non-destructive leaf area measurement in maize (Zea mays L.).

    Science.gov (United States)

    Sezer, Ismail; Oner, Fatih; Mut, Zeki

    2009-09-01

    In this research, leaf area prediction model was developed for some leaf-used maize (Zea mays L.) cultivars namely Coluna, Luce, Maveric, Ranchero, TTM-813, Zamora and RX-788 grown in Black Sea region of Turkey. Lamina width, length and leaf area were measured without destroying the leaf to develop the models. The actual leaf areas of the plants were measured by PLACOM Digital Planimeter and multiple regression analysis with Excel 2003 computer package program was performed for the plants separately. The produced leaf area prediction models in the present study were formulized as LA = a - (b x W2) + [c x (W x L)] where LA is leaf area, W is leaf width, L is leaf length and a, b, c are coefficiencies. R2 values for maize cultivars tested varied with species from 0.95 in Luce to 0.98 in Maveric. All R2 values and standard errors were found to be significant at the p < 0.001 level.

  2. Growth promoting characteristics of rhizobacteria and AM Fungi for biomass amelioration of Zea mays

    Directory of Open Access Journals (Sweden)

    Kumar Manoj

    2015-01-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR and mycorrhiza were evaluated on the growth (biomass and yield of Zea mays. In the present study, selective rhizospheric PGPR (Azotobacter chroococcum, Pseudomonas aeruginosa, Azospirillum brasilense and Streptomyces sp. and a combination of six strains of arbuscular mycorrhizal fungi (AMF (Acaulospora morrowae, Gigaspora margarita, Glomus constrictum, Glomus mossae, Glomus aggregatum and Scutellospora calospora were isolated and identified with standard methods and 16S rRNA sequence analysis. PGPR and AMF were checked for their growth-promoting behavior under specific treatment conditions. The 30-48-day-old treated plants in all combinations showed a significantly higher mass value. The average dry weight from the shoot was in a range from 41-52% as compared to the control. This increase also translated into a higher mass value of the roots. Overall, an 82% growth rate was observed in terms of height as the consequence of biomass production, specifically in the case of AMF + rhizobacteria combination. We report an efficient, sustainable and cost-effective biofertilizer for enhanced biomass of Z. mays, one of the staple food crops worldwide.

  3. Perennial aneuploidy as a potential material for gene introgression between maize and Zea perennis

    Institute of Scientific and Technical Information of China (English)

    FU Jie; TANG Qi-lin; YANG Xiu-yan; CHENG Ming-jun; LÜ Gui-hua; WANG Pei; WU Yuan-qi; ZHENG Ming-min; ZHOU Shu-feng; RONG Ting-zhao

    2015-01-01

    Hybridization, which al ows for gene lfow between crops, is dififcult between maize and Zea perennis. In this study, we aim to initiate and study gene lfow between maize and Z. perennis via a special aneuploid plant (MDT) derived from an interspeciifc hybrid of the two species. The chromosome constitution and morphological characters of MDT as wel as certain backcross progenies were examined. Results from genomic in situ hybridization (GISH) indicate that aneuploid MDT consisted of nine maize chromosomes and 30 Z. perennis chromosomes. The backcross progenies of MDT×maize displayed signiifcant diversity of vegetative and ear morphology;several unusual plants with speciifc chromosome constitution were founded in its progenies. Some special perennial progeny with several maize chromosomes were obtained by backcrossing MDT with Z. perennis, and the ifrst whole chromosome introgression from maize to Z. perennis was detected in this study. With this novel material and method, a number of maize-tetraploid teosinte addition or substitution lines can be generated for further study, which has great signiifcance to maize and Z. perennis genetic research, especial y for promoting introgression and transferring desirable traits.

  4. Natural endophytic association between Rhizobium etli and maize (Zea mays L.).

    Science.gov (United States)

    Gutiérrez-Zamora, M L; Martínez-Romero, E

    2001-10-04

    Maize (Zea mays) and bean (Phaseolus vulgaris) have been traditionally grown in association for thousands of years in Mesoamerica. From surface sterilized maize roots, we have isolated over 60 Rhizobium strains that correspond to Rhizobium etli bv. phaseoli (the main symbiont of bean) on the basis of 16S rRNA gene restriction patterns, metabolic enzyme electropherotypes, organization of nif genes, and the ability to nodulate beans. The colonization capacity of some of the isolates was tested with an unimproved maize cultivar and with 30 maize land races. Increases in plant dry weight upon R. etli inoculation were recorded with some of the land races, and these increases may be related to plant growth promotion effects. Additionally, from within maize grown in monoculture we have also recovered R. etli isolates recognizable by their 16S rRNA gene types, which lack nif genes and are incapable of nodulating bean. These strains are presumed to correspond to the earlier described non-symbiotic R. etli obtained from bean rhizosphere.

  5. The nitrate reductase inhibitor, tungsten, disrupts actin microfilaments in Zea mays L.

    Science.gov (United States)

    Adamakis, Ioannis-Dimosthenis S; Panteris, Emmanuel; Eleftheriou, Eleftherios P

    2014-05-01

    Tungsten is a widely used inhibitor of nitrate reductase, applied to diminish the nitric oxide levels in plants. It was recently shown that tungsten also has heavy metal attributes. Since information about the toxic effects of tungsten on actin is limited, and considering that actin microfilaments are involved in the entry of tungsten inside plant cells, the effects of tungsten on them were studied in Zea mays seedlings. Treatments with sodium tungstate for 3, 6, 12 or 24 h were performed on intact seedlings and seedlings with truncated roots. Afterwards, actin microfilaments in meristematic root and leaf tissues were stained with fluorescent phalloidin, and the specimens were examined by confocal laser scanning microscopy. While the actin microfilament network was well organized in untreated seedlings, in tungstate-treated ones it was disrupted in a time-dependent manner. In protodermal root cells, the effects of tungsten were stronger as cortical microfilaments were almost completely depolymerized and the intracellular ones appeared highly bundled. Fluorescence intensity measurements confirmed the above results. In the meristematic leaf tissue of intact seedlings, no depolymerization of actin microfilaments was noticed. However, when root tips were severed prior to tungstate application, both cortical and endoplasmic actin networks of leaf cells were disrupted and bundled after 24 h of treatment. The differential response of root and leaf tissues to tungsten toxicity may be due to differential penetration and absorption, while the effects on actin microfilaments could not be attributed to the nitric oxide depletion by tungsten.

  6. Genomewide analysis of LATERAL ORGAN BOUNDARIES Domain gene family in Zea mays

    Indian Academy of Sciences (India)

    Yue-Min Zhang; Shi-Zhong Zhang; Cheng-Chao Zheng

    2014-04-01

    The investigation of transcription factor (TF) families is a major focus of postgenomic research. The plant-specific ASYMMETRIC LEAVES2-LIKE (ASL) / LATERAL ORGAN BOUNDARIES Domain (LBD) proteins constitute a major zincfinger-like-domain transcription factor family, and regulate diverse biological processes in plants. However, little is known about LBD genes in maize (Zea mays). In this study, a total of 44 LBD genes were identified in maize genome and were phylogenetically clustered into two groups (I and II), together with LBDs from Arabidopsis. The predicted maize LBDs were distributed across all the 10 chromosomes with different densities. In addition, the gene structures of maize LBDs were analysed. The expression profiles of the maize LBD genes under normal growth conditions were analysed by microarray data and qRT-PCR. The results indicated that LBDs might be involved in various aspects of physiological and developmental processes in maize. To our knowledge, this is the first report of a genomewide analysis of the maize LBD gene family, which would provide valuable information for understanding the classification and putative functions of the gene family.

  7. Traditionally used medicinal plants against uncomplicated urinary tract infections: Are unusual, flavan-4-ol- and derhamnosylmaysin derivatives responsible for the antiadhesive activity of extracts obtained from stigmata of Zea mays L. against uropathogenic E. coli and Benzethonium chloride as frequent contaminant faking potential antibacterial activities?

    Science.gov (United States)

    Rafsanjany, Nasli; Sendker, Jandirk; Lechtenberg, Matthias; Petereit, Frank; Scharf, Birte; Hensel, Andreas

    2015-09-01

    The dried stigmata from Zea mays L. are used traditionally for the treatment of uncomplicated urinary tract infections. A recent screening has indicated that hydroalcoholic extract of the herbal material inhibits the adhesion of uropathogenic Escherichia coli (UPEC) to T24 bladder cells. For verification of these data EtOH-water (1:1) extracts from 4 different batches of Maydis stigmata were investigated. Within an in vitro adhesion assay (UPEC strain 2980 and human T24 bladder cells) a dose-dependent antiadhesive activity against UPEC was verified (IC50 1040μg/mL). Bioassay guided fractionation of M. stigmata, batch S1, by EtOH-water extraction, followed by chromatography on Sephadex LH20 revealed two active fractions (I and XI). Further purification of fraction I and structure elucidation of the isolated compound revealed the presence of significant amounts of the biocide benzethonium chloride as contaminant. Benzethonium chloride was also identified in subsequent investigations in 2 different batches of M. stigmata. The presence of such nondeclared and illegal contaminants in the herbal raw material market has to be discussed intensively. From benzethonium-free raw material (batch S2) as well as from batch S1 fraction XI was further fractionated by MPLC and preparative HPLC, leading to a still complex subfraction XIG, which was analyzed by UHPLC/+ESI-QTOF-MS analysis. Advanced data processing and species-metabolite relationship database revealed the tentatively existence of the unusual C-glycosidic flavones derhamnosylmaysin (6), 3'-deoxyrhamnosylmaysin (4), 3'-O-methylderhamnosylmaysin (3), apiferol (2) and alternanthin (8) which might be related to the antiadhesive activity of this subfraction against UPEC.

  8. Effets du froid sur les stades précoces de développement du maïs (Zea mays L. (synthèse bibliographique

    Directory of Open Access Journals (Sweden)

    Riva-Roveda, L.

    2015-01-01

    Full Text Available Effects of cold temperatures on the early stages of maize (Zea mays L.. A review. Introduction. Maize is a crop of great economical importance. Despite its tropical origin and its high sensitivity to low temperatures, maize is now cultivated in a wide range of latitudes. To maintain competitive yields, many genetic and agricultural adaptations have been implemented. Literature. Plant responses to environmental stresses such as drought or cold have been extensively studied. This article reviews the progress and current knowledge regarding the effects of non-freezing cold temperatures on maize plants, from germination to floral transition. During the early stages of development, cold alters plant phenology and productivity, mainly because of its negative impact on photosynthesis. Plant growth is affected and secondary osmotic and oxidative stresses induce cell damage. Conclusion. A better understanding of the effects of cold will allow the development of new strategies for improving plant tolerance through the use of various physiological, genetic and molecular approaches.

  9. Effect of Nitrogen Nutritional Stress on some Mineral Nutrients and Photosynthetic Apparatus of Zea mays L. and Vigna unguiculata L.

    Directory of Open Access Journals (Sweden)

    Akinbode Foluso OLOGUNDUDU

    2013-08-01

    Full Text Available The study investigated the responses of maize (Zea mays L. and cowpea (Vigna unguiculata L. Walp. seedlings metabolic activities and photosynthetic apparatus to nitrogen nutritional stress. Germination of seeds was done using treated sand in sixty plastic pots and the seedlings were divided into four nutrient regimes. A group of the seedlings was nutrient stressed by administering 200 ml of complete nutrient solution minus nitrogen (-N while the other groups were fed with five times (X5N and ten times (X10N the optimal concentration of nitrogen and the last regime was fed with full nutrient solution (FN. The photosynthetic parameters studied included chlorophylls ‘a’ and ‘b’ respectively; carotenes and xanthophyll while the mineral elements investigated include potassium, calcium and magnesium. The result of the growth analysis showed that nitrogen deficiency promotes an increase in the content of abscisic acid (ABA, causing stomatal closure and a reduction in photosynthesis. This explains the higher rate of leaf abscission in -N plants. A comparison of calcium ion and magnesium ion concentrations in both optimal and stressed conditions reveals that the two ions show antagonism in uptake. There is a correlation between nitrogen and magnesium accumulation as magnesium ion plays a vital role in chlorophyll biosynthesis, protein synthesis and photosynthesis. The pattern of accumulation of photosynthetic apparatus in both maize and cowpea follow a similar pattern. Chlorophyll a dictated the growth pattern of other photosynthetic apparatus in both Zea mays and Vigna unguiculata.

  10. Presence of Zea luxurians (Durieu and Ascherson) Bird in Southern Brazil: Implications for the Conservation of Wild Relatives of Maize

    Science.gov (United States)

    2015-01-01

    Records of the occurrence of wild relatives of maize in South American lowlands are unprecedented, especially in sympatric coexistence with landraces. This fact is relevant, because regions of occurrence of wild relatives of cultivated plants should be a priority for conservation, even if they do not correspond to the center of origin of the species. The aim of this study was to identify and characterize the wild relatives of maize in the Far West of Santa Catarina, southern Brazil. Therefore, phenotypic characterization was performed for five populations, based on 22 morphological traits deemed as fundamental for classifying the species of the genus Zea, and validated through the characterization of chromosomal knobs of two populations. The occurrence and distribution of teosinte populations were described through semi-structured interviews applied to a sample of 305 farmers. A total of 136 teosinte populations were identified; 75% of them occur spontaneously, 17% are cultivated populations, and 8% occur both ways, for the same farm. Populations that were characterized morphologically had trapezoidal fruits mostly, upright tassel branch (4–18), non-prominent main branch and glabrous glumes, with two protruding outer ribs and 8 inner ribs, on average. Cytogenetic analysis identified 10 pairs of homologous chromosomes (2n = 20) with 26 knobs, located in the terminal region of all chromosomes. The similarity of these results with the information reported in the literature indicates that the five populations of wild relatives of maize in this region of Santa Catarina belong to the botanical species Zea luxurians. PMID:26488577

  11. 3D-MRI rendering of the anatomical structures related to acupuncture points of the Dai mai, Yin qiao mai and Yang qiao mai meridians within the context of the WOMED concept of lateral tension: implications for musculoskeletal disease

    Directory of Open Access Journals (Sweden)

    Kremser Christian

    2007-04-01

    Full Text Available Abstract Background A conceptual model of lateral muscular tension in patients presenting thyroid associated ophthalmopathy (TAO has been recently described. Clinical improvement has been achieved by using acupuncture on points belonging to the so-called extraordinary meridians. The aim of this study was to characterize the anatomical structures related to these acupuncture points by means of 3D MRI image rendering relying on external markers. Methods The investigation was carried out the index case patient of the lateral tension model. A licensed medical acupuncture practitioner located the following acupuncture points: 1 Yin qiao mai meridian (medial ankle: Kidney 3, Kidney 6, the plantar Kidney 6 (Nan jing description; 2 Yang qiao mai meridian (lateral ankle: Bladder 62, Bladder 59, Bladder 61, and the plantar Bladder 62 (Nan jing description; 3 Dai mai meridian (wait: Liver 13, Gall bladder 26, Gall bladder 27, Gall bladder 28, and Gall bladder 29. The points were marked by taping a nitro-glycerin capsule on the skin. Imaging was done on a Siemens Magnetom Avanto MR scanner using an array head and body coil. Mainly T1-weighted imaging sequences, as routinely used for patient exams, were used to obtain multi-slice images. The image data were rendered in 3D modus using dedicated software (Leonardo, Siemens. Results Points of the Dai mai meridian – at the level of the waist – corresponded to the obliquus externus abdominis and the obliquus internus abdominis. Points of the Yin qiao mai meridian – at the medial side of the ankle – corresponded to tendinous structures of the flexor digitorum longus as well as to muscular structures of the abductor hallucis on the foot sole. Points of the Yang qiao mai meridian – at the lateral side of the ankle – corresponded to tendinous structures of the peroneus brevis, the peroneous longus, and the lateral surface of the calcaneus and close to the foot sole to the abductor digiti minimi

  12. Study of cell-differentiation and assembly of photosynthetic proteins during greening of etiolated Zea mays leaves using confocal fluorescence microspectroscopy at liquid-nitrogen temperature.

    Science.gov (United States)

    Shibata, Yutaka; Katoh, Wataru; Tahara, Yukari

    2013-04-01

    Fluorescence microspectroscopy observations were used to study the processes of cell differentiation and assemblies of photosynthesis proteins in Zea mays leaves under the greening process. The observations were done at 78K by setting the sample in a cryostat to avoid any undesired progress of the greening process during the measurements. The lateral and axial spatial resolutions of the system were 0.64μm and 4.4μm, respectively. The study revealed the spatial distributions of protochlorophyllide (PChld) in both the 632-nm-emitting and 655-nm-emitting forms within etiolated Zea mays leaves. The sizes of the fluorescence spots attributed to the former were larger than those of the latter, validating the assignment of the former and latter to the prothylakoid and prolamellar bodies, respectively. In vivo microspectroscopy observations of mature Zea mays leaves confirmed the different photosystem II (PS I)/photosystem I (PS II) ratio between the bundle sheath (BS) and mesophyll (MS) cells, which is specific for C4-plants. The BS cells in Zea mays leaves 1h after the initiation of the greening process tended to show fluorescence spectra at shorter wavelength side (at around 679nm) than the MS cells (at around 682nm). The 679-nm-emitting chlorophyll-a form observed mainly in the BS cells was attributed to putative precursor complexes to PS I. The BS cells under 3-h greening showed higher relative intensities of the PS I fluorescence band at around 735nm, suggesting the reduced PS II amount in the BS cells in this greening stage. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Effects of Tang Mai Kang Capsule on Angioneurotic Lesions in Alloxan-Induced Diabetic Mice

    Institute of Scientific and Technical Information of China (English)

    李华; 王军; 高丽君; 郭永成

    2004-01-01

    The effects of Tang Mai Kang Capsule (糖脉康胶囊) on blood sugar level, gangrene of the tail-tip, pain threshold and learning and memory abilities were investigated in alloxan-induced diabetic mice. The results showed that Tang Mai Kang Capsule could significantly decrease blood sugar level and incidence rate of gangrene of the tail-tip, increase pain threshold, and strengthen learning and memory abilities, suggesting that Tang Mai Kang Capsule functions to decrease blood sugar level and improve the complicated angioneurotic lesions of diabetes.

  14. Chelant-assisted phytoextraction and accumulation of Zn by Zea mays.

    Science.gov (United States)

    Gheju, M; Stelescu, I

    2013-10-15

    Zea mays plants were exposed to soils with concentrations of Zn ranging from 64 to 1800 mg kg(-1) dw, and the efficiency of three selected chelating agents (trisodium citrate (CI), disodium oxalate (OX) and disodium dihydrogen ethylene-diamine-tetraacetate (EDTA)) in enhancing metal phytoextraction was compared. Zn concentration in plant tissues increased in conjunction with the metal concentration of the soil. EDTA was found to be the most efficient chelating amendment, increasing concentrations of Zn in shoots from 88 mg kg(-1) dw, at 64 mg kg(-1) dw soil, to 8026 mg kg(-1) dw at 1800 mg kg(-1) dw soil. The overall orders of BCFs and TFs which resulted from this study are: EDTA > H2O > OX > CI, and EDTANa2 > OX > CI > H2O, respectively. The more effective uptake of Zn by plants for the control treatment (distilled water only) than for CI and OX was attributed to the neutral or slightly alkaline pH of the two chelant irrigation solutions. Instead, EDTA had a favorable effect on Zn uptake from soil due to its additive chelating and acidifying properties. Among the three chelants, only EDTA significantly increased the Zn phytoextraction potential of Z. mays, while CI and OX induced a low metal uptake from soil by plants. Although Z. mays has a lower Zn accumulation capacity than the hyperaccumulator Thlaspi caerulescens, it could be considered as a potential phytoremediator of soils with elevated Zn concentrations, especially when metal pollution extends to depths greater than 20 cm. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Enhanced uptake of As, Zn, and Cu by Vetiveria zizanioides and Zea mays using chelating agents.

    Science.gov (United States)

    Chiu, K K; Ye, Z H; Wong, M H

    2005-09-01

    Vetiveria zizaniodes (vetiver) is commonly known for its effectiveness in soil and sediment erosion control. It can tolerate to extreme soil conditions and produce a high biomass even growing in contaminated areas. Zea mays (maize) can also produce a very high biomass with a fast growth rate and possesses some degree of metal tolerance. A greenhouse study was conducted to investigate the feasibility of using vetiver and maize for remediation of arsenic (As)-, zinc (Zn-), and copper (Cu)-amended soils and evaluate the effects of chelating agents on metal uptake by these plants. Vetiver had a better growth (dry weight yield of root and shoot) than maize under different treatment conditions. The effects of different chelating agents on As, Zn, and Cu extraction from soil to soil solution were studied. Among the nine chelating agents used, it was noted that 20 mmol NTA could maximize As and Zn bioavailability, while 20 mmol HEIDA could maximize Cu bioavailability in the soil solution. The surge time in maximizing metal uptake ranged from 16 to 20 days which indicated that timing on plant harvest was an important factor in enhanced metal accumulation. In general, vetiver was a more suitable plant species than maize in terms of phytoextraction of metals from metal-contaminated soil. Application of NTA in As-amended soil and HEIDA in Cu-amended soil at the rate of 20 mmol kg(-1) increased 3-4-fold of As and Cu in shoot of both plants, whereas application of NTA (20 mmol kg(-1)) increased 37- and 1.5-fold of Zn accumulation in shoot of vetiver and maize, respectively. The potential environmental risk of metal mobility caused by chelating agents used for phytoextraction should not be overlooked.

  16. Modulation of thiamine metabolism in Zea mays seedlings under conditions of abiotic stress.

    Science.gov (United States)

    Rapala-Kozik, Maria; Kowalska, Ewa; Ostrowska, Katarzyna

    2008-01-01

    The responses of plants to abiotic stress involve the up-regulation of numerous metabolic pathways, including several major routes that engage thiamine diphosphate (TDP)-dependent enzymes. This suggests that the metabolism of thiamine (vitamin B1) and its phosphate esters in plants may be modulated under various stress conditions. In the present study, Zea mays seedlings were used as a model system to analyse for any relation between the plant response to abiotic stress and the properties of thiamine biosynthesis and activation. Conditions of drought, high salt, and oxidative stress were induced by polyethylene glycol, sodium chloride, and hydrogen peroxide, respectively. The expected increases in the abscisic acid levels and in the activities of antioxidant enzymes including catalase, ascorbate peroxidase, and glutathione reductase were found under each stress condition. The total thiamine compound content in the maize seedling leaves increased under each stress condition applied, with the strongest effects on these levels observed under the oxidative stress treatment. This increase was also found to be associated with changes in the relative distribution of free thiamine, thiamine monophosphate (TMP), and TDP. Surprisingly, the activity of the thiamine synthesizing enzyme, TMP synthase, responded poorly to abiotic stress, in contrast to the significant enhancement found for the activities of the TDP synthesizing enzyme, thiamine pyrophosphokinase, and a number of the TDP/TMP phosphatases. Finally, a moderate increase in the activity of transketolase, one of the major TDP-dependent enzymes, was detectable under conditions of salt and oxidative stress. These findings suggest a role of thiamine metabolism in the plant response to environmental stress.

  17. Arsenic uptake by arbuscular mycorrhizal maize (Zea mays L.) grown in an arsenic-contaminated soil with added phosphorus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As)uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment. Non-mycorrhizal and zero-P addition controls were included. Plant biomass and concentrations and uptake of As, P, and other nutrients, AM colonization, root lengths, and hyphal length densities were determined. The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium. Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments, but shoot and root biomass of AM plants was depressed by P application. AM fungal inoculation decreased shoot As concentrations when no P was added, and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition, respectively. Shoot and root uptake of P, Mn, Cu, and Zn increased, but shoot Fe uptake decreased by 44.6%, with inoculation,when P was added. P addition reduced shoot P, Fe, Mn, Cu, and Zn uptake of AM plants, but increased root Fe and Mn uptake of the nonmycorrhizal ones. AM colonization therefore appeared to enhance plant tolerance to As in low P soil, and have some potential for the phytostabilization of As-contaminated soil, however, P application may introduce additional environmental risk by increasing soil As mobility.

  18. Arsenic uptake by arbuscular mycorrhizal maize (Zea mays L.) grown in an arsenic-contaminated soil with added phosphorus.

    Science.gov (United States)

    Xia, Yun-sheng; Chen, Bao-dong; Christie, Peter; Smith, F Andrew; Wang, You-shan; Li, Xiao-lin

    2007-01-01

    The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment. Non-mycorrhizal and zero-P addition controls were included. Plant biomass and concentrations and uptake of As, P, and other nutrients, AM colonization, root lengths, and hyphal length densities were determined. The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium. Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments, but shoot and root biomass of AM plants was depressed by P application. AM fungal inoculation decreased shoot As concentrations when no P was added, and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition, respectively. Shoot and root uptake of P, Mn, Cu, and Zn increased, but shoot Fe uptake decreased by 44.6%, with inoculation, when P was added. P addition reduced shoot P, Fe, Mn, Cu, and Zn uptake of AM plants, but increased root Fe and Mn uptake of the nonmycorrhizal ones. AM colonization therefore appeared to enhance plant tolerance to As in low P soil, and have some potential for the phytostabilization of As-contaminated soil, however, P application may introduce additional environmental risk by increasing soil As mobility.

  19. Growth, cadmium uptake and accumulation of maize (Zea mays L.) under the effects of arbuscular mycorrhizal fungi.

    Science.gov (United States)

    Liu, Lingzhi; Gong, Zongqiang; Zhang, Yulong; Li, Peijun

    2014-12-01

    The effects of three arbuscular mycorrhizal fungi isolates on Cd uptake and accumulation by maize (Zea mays L.) were investigated in a planted pot experiment. Plants were inoculated with Glomus intraradices, Glomus constrictum and Glomus mosseae at three different Cd concentrations. The results showed that root colonization increased with Cd addition during a 6-week growth period, however, the fungal density on roots decreased after 9-week growth in the treatments with G. constrictum and G. mosseae isolates. The percentage of mycorrhizal colonization by the three arbuscular mycorrhizal fungi isolates ranged from 22.7 to 72.3%. Arbuscular mycorrhizal fungi inoculations decreased maize biomass especially during the first 6-week growth before Cd addition, and this inhibitory effect was less significant with Cd addition and growth time. Cd concentrations and uptake in maize plants increased with arbuscular mycorrhizal fungi colonization at low Cd concentration (0.02 mM): nonetheless, it decreased at high Cd concentration (0.20 mM) after 6-week growth period. Inoculation with G. constrictum isolates enhanced the root Cd concentrations and uptake, but G. mosseae isolates showed the opposite results at high Cd concentration level after 9 week growth period, as compared to non-mycorrhizal plants. In conclusion, maize plants inoculated with arbuscular mycorrhizal fungi were less sensitive to Cd stress than uninoculated plants. G. constrictum isolates enhanced Cd phytostabilization and G. mosseae isolates reduced Cd uptake in maize (Z. mays L.).

  20. Antimicrobial peptide inhibition of fungalysin proteases that target plant type 19 Family IV defense chitinases

    Science.gov (United States)

    Cereal crops and other plants produce secreted seed chitinases that reduce pathogenic infection, most likely by targeting the fungal chitinous cell wall. We have shown that corn (Zea mays) produces three GH family 19, plant class IV chitinases, that help in protecting the plant against Fusarium and ...

  1. Planting geometry and plant population affect dryland maize grain yield and harvest index

    Science.gov (United States)

    Water for dryland grain production in the Texas panhandle is limited. Agronomic practices such as reduction in plant population or change in sowing time may help increase maize (Zea mays L.) yield potential. Tiller formation under dryland conditions leads to more vegetative growth and reduced yield....

  2. Moskva 9. mai kutse külvab tüli Saksamaalgi / Arko Olesk

    Index Scriptorium Estoniae

    Olesk, Arko, 1981-

    2005-01-01

    Saksamaa kristlik-demokraatliku fraktsiooni liige Friedbert Pfüger ja sotsiaaldemokraatide fraktsiooni aseesimees Gernot Erler esitavad oma seisukohti, millise sõnumiga peaks kantsler Gerhard Schröder esinema 9. mai pidustustel Moskvas

  3. Poliitiline mäsu 9. mai pärast / Tanel Mazur

    Index Scriptorium Estoniae

    Mazur, Tanel, 1971-

    2005-01-01

    Erimeelsused Vene Erakonna Eestis ja Reformierakonna Narva osakonna vahel, ei suudeta jõuda kokkuleppele 9. mai tähistamise suhtes. Politsei algatas väärteomenetluse Vene Erakonna Eestis poolt Narvas korraldatud aktsiooni asjas

  4. A Modular Artificial Intelligence Inference Engine System (MAIS) for support of on orbit experiments

    Science.gov (United States)

    Hancock, Thomas M., III

    1994-01-01

    This paper describes a Modular Artificial Intelligence Inference Engine System (MAIS) support tool that would provide health and status monitoring, cognitive replanning, analysis and support of on-orbit Space Station, Spacelab experiments and systems.

  5. In-vivo visualisation of the anatomical structures related to the acupuncture points Dai mai and Shen mai by MRI: A single-case pilot study

    Directory of Open Access Journals (Sweden)

    Diemling Markus

    2007-03-01

    Full Text Available Abstract Background The concept of acupuncture point localisation in Traditional Chinese Medicine (TCM is based on millenary practical experience. Modern imaging methods such as PET, MRI and SPECT have been used primary for the investigation of the mechanisms of action of acupuncture. In this pilot single-case study we have evaluated the technical possibilities for in-vivo imaging of the anatomical relations of acupuncture points using state of the art MRI. Methods Preliminary experiments relating to the quality of acupuncture needles under the setting of MRI were done both with stainless steel and gold needles. In a second step, in-vivo imaging was carried out. A licensed acupuncture practitioner (RM chose two points belonging to the so-called extraordinary vessels. In 2 sequential, separate procedures, he inserted himself gold acupuncture needles using a neutral technique (known as Ping Bu Ping Xie into the Dai mai and Shen mai points, i.e. gall bladder 26 and bladder 62. Imaging was done on a Siemens Magnetom Avanto MR scanner using a head array and body coil. Mainly T1-weighted imaging sequences, as routinely used for patient exams, were used to obtain multi-slice images. Results In the preliminary experiments only acupuncture needles made of gold showed enough stability in order to be used for further imaging procedures. Using an onion and a banana as an object, further studies showed that the gold needles produced a void defect that corresponds to the tip of the inserted needle, while at the same time an artefactually increased diameter was observed. The in-vivo experiments showed that the Dai mai point was in relation to the abdominal internal oblique muscle. The Shen mai point artefact showed up close to the longus and brevis peroneal tendons at the fibular malleolus. Side effects related to heating or burning were not observed. Improved anatomical recognition was obtained using 3D-volume rendering techniques. Conclusion Through an

  6. Allocation and source attribution of lead and cadmium in maize (Zea mays L.) impacted by smelting emissions

    Energy Technology Data Exchange (ETDEWEB)

    Bi Xiangyang [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China); Key Laboratory of Biogeology and Environmental Geology, Ministry of Education, China University of Geosciences, Wuhan 430074 (China); Feng Xinbin [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China)], E-mail: fengxinbin@vip.skleg.cn; Yang Yuangen [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China); Li Xiangdong; Shin, Grace P.Y. [Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Li Feili [College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Qiu Guangle; Li Guanghui; Liu Taoze; Fu Zhiyou [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China)

    2009-03-15

    Plants grown in contaminated areas may accumulate trace metals to a toxic level via their roots and/or leaves. In the present study, we investigated the distribution and sources of Pb and Cd in maize plants (Zea mays L.) grown in a typical zinc smelting impacted area of southwestern China. Results showed that the smelting activities caused significantly elevated concentrations of Pb and Cd in the surrounding soils and maize plants. Pb isotope data revealed that the foliar uptake of atmospheric Pb was the dominant pathway for Pb to the leaf and grain tissues of maize, while Pb in the stalk and root tissues was mainly derived from root uptake. The ratio of Pb to Cd concentrations in the plants indicated that Cd had a different behavior from Pb, with most Cd in the maize plants coming from the soil via root uptake. - The sources and pathways of Pb and Cd accumulated in maize were assessed using Pb isotopes and Pb/Cd ratios.

  7. The maize (Zea mays ssp. mays var. B73 genome encodes 33 members of the purple acid phosphatase gene family

    Directory of Open Access Journals (Sweden)

    Eliécer eGonzález Muñoz

    2015-05-01

    Full Text Available Purple acid phosphatases (PAPs play an important role in plant phosphorus nutrition, both by liberating phosphorus from organic sources in the soil and by modulating distribution within the plant throughout growth and development. Furthermore, members of the PAP protein family have been implicated in a broader role in plant mineral homeostasis, stress responses and development. We have identified 33 candidate PAP encoding gene models in the maize (Zea mays ssp. mays var. B73 reference genome. The maize Pap family includes a clear single-copy ortholog of the Arabidopsis gene AtPAP26, shown previously to encode both major intracellular and secreted acid phosphatase activities. Certain groups of PAPs present in Arabidopsis, however, are absent in maize, while the maize family contains a number of expansions, including a distinct radiation not present in Arabidopsis. Analysis of RNA-sequencing based transcriptome data revealed accumulation of maize Pap transcripts in multiple plant tissues at multiple stages of development, and increased accumulation of specific transcripts under low phosphorus availability. These data suggest the maize PAP family as a whole to have broad significance throughout the plant life cycle, while highlighting potential functional specialization of individual family members.

  8. The maize (Zea mays ssp. mays var. B73) genome encodes 33 members of the purple acid phosphatase family.

    Science.gov (United States)

    González-Muñoz, Eliécer; Avendaño-Vázquez, Aida-Odette; Montes, Ricardo A Chávez; de Folter, Stefan; Andrés-Hernández, Liliana; Abreu-Goodger, Cei; Sawers, Ruairidh J H

    2015-01-01

    Purple acid phosphatases (PAPs) play an important role in plant phosphorus nutrition, both by liberating phosphorus from organic sources in the soil and by modulating distribution within the plant throughout growth and development. Furthermore, members of the PAP protein family have been implicated in a broader role in plant mineral homeostasis, stress responses and development. We have identified 33 candidate PAP encoding gene models in the maize (Zea mays ssp. mays var. B73) reference genome. The maize Pap family includes a clear single-copy ortholog of the Arabidopsis gene AtPAP26, shown previously to encode both major intracellular and secreted acid phosphatase activities. Certain groups of PAPs present in Arabidopsis, however, are absent in maize, while the maize family contains a number of expansions, including a distinct radiation not present in Arabidopsis. Analysis of RNA-sequencing based transcriptome data revealed accumulation of maize Pap transcripts in multiple plant tissues at multiple stages of development, and increased accumulation of specific transcripts under low phosphorus availability. These data suggest the maize PAP family as a whole to have broad significance throughout the plant life cycle, while highlighting potential functional specialization of individual family members.

  9. Dehydration stress memory genes of Zea mays; comparison with Arabidopsis thaliana

    Science.gov (United States)

    2014-01-01

    Background Pre-exposing plants to diverse abiotic stresses may alter their physiological and transcriptional responses to a subsequent stress, suggesting a form of “stress memory”. Arabidopsis thaliana plants that have experienced multiple exposures to dehydration stress display transcriptional behavior suggesting “memory” from an earlier stress. Genes that respond to a first stress by up-regulating or down-regulating their transcription but in a subsequent stress provide a significantly different response define the ‘memory genes’ category. Genes responding similarly to each stress form the ‘non-memory’ category. It is unknown whether such memory responses exists in other Angiosperm lineages and whether memory is an evolutionarily conserved response to repeated dehydration stresses. Results Here, we determine the transcriptional responses of maize (Zea mays L.) plants that have experienced repeated exposures to dehydration stress in comparison with plants encountering the stress for the first time. Four distinct transcription memory response patterns similar to those displayed by A. thaliana were revealed. The most important contribution is the evidence that monocot and eudicot plants, two lineages that have diverged 140 to 200 M years ago, display similar abilities to ‘remember’ a dehydration stress and to modify their transcriptional responses, accordingly. The highly sensitive RNA-Seq analyses allowed to identify genes that function similarly in the two lineages, as well as genes that function in species-specific ways. Memory transcription patterns indicate that the transcriptional behavior of responding genes under repeated stresses is different from the behavior during an initial dehydration stress, suggesting that stress memory is a complex phenotype resulting from coordinated responses of multiple signaling pathways. Conclusions Structurally related genes displaying the same memory responses in the two species would suggest conservation

  10. Characterization and Transposon Mutagenesis of the Maize (Zea mays) Pho1 Gene Family

    Science.gov (United States)

    Salazar-Vidal, M. Nancy; Acosta-Segovia, Edith; Sánchez-León, Nidia; Ahern, Kevin R.; Brutnell, Thomas P.; Sawers, Ruairidh J. H.

    2016-01-01

    Phosphorus is an essential nutrient for all plants, but also one of the least mobile, and consequently least available, in the soil. Plants have evolved a series of molecular, metabolic and developmental adaptations to increase the acquisition of phosphorus and to maximize the efficiency of use within the plant. In Arabidopsis (Arabidopsis thaliana), the AtPHO1 protein regulates and facilitates the distribution of phosphorus. To investigate the role of PHO1 proteins in maize (Zea mays), the B73 reference genome was searched for homologous sequences, and four genes identified that were designated ZmPho1;1, ZmPho1;2a, ZmPho1;2b and ZmPho1;3. ZmPho1;2a and ZmPho1;2b are the most similar to AtPHO1, and represent candidate co-orthologs that we hypothesize to have been retained following whole genome duplication. Evidence was obtained for the production of natural anti-sense transcripts associated with both ZmPho1;2a and ZmPho1;2b, suggesting the possibility of regulatory crosstalk between paralogs. To characterize functional divergence between ZmPho1;2a and ZmPho1;2b, a program of transposon mutagenesis was initiated using the Ac/Ds system, and, here, we report the generation of novel alleles of ZmPho1;2a and ZmPho1;2b. PMID:27648940

  11. Zea mays iRS1563: a comprehensive genome-scale metabolic reconstruction of maize metabolism.

    Science.gov (United States)

    Saha, Rajib; Suthers, Patrick F; Maranas, Costas D

    2011-01-01

    The scope and breadth of genome-scale metabolic reconstructions have continued to expand over the last decade. Herein, we introduce a genome-scale model for a plant with direct applications to food and bioenergy production (i.e., maize). Maize annotation is still underway, which introduces significant challenges in the association of metabolic functions to genes. The developed model is designed to meet rigorous standards on gene-protein-reaction (GPR) associations, elementally and charged balanced reactions and a biomass reaction abstracting the relative contribution of all biomass constituents. The metabolic network contains 1,563 genes and 1,825 metabolites involved in 1,985 reactions from primary and secondary maize metabolism. For approximately 42% of the reactions direct literature evidence for the participation of the reaction in maize was found. As many as 445 reactions and 369 metabolites are unique to the maize model compared to the AraGEM model for A. thaliana. 674 metabolites and 893 reactions are present in Zea mays iRS1563 that are not accounted for in maize C4GEM. All reactions are elementally and charged balanced and localized into six different compartments (i.e., cytoplasm, mitochondrion, plastid, peroxisome, vacuole and extracellular). GPR associations are also established based on the functional annotation information and homology prediction accounting for monofunctional, multifunctional and multimeric proteins, isozymes and protein complexes. We describe results from performing flux balance analysis under different physiological conditions, (i.e., photosynthesis, photorespiration and respiration) of a C4 plant and also explore model predictions against experimental observations for two naturally occurring mutants (i.e., bm1 and bm3). The developed model corresponds to the largest and more complete to-date effort at cataloguing metabolism for a plant species.

  12. Pengaruh Jarak Tanam dan Pemangkasan terhadap Kualitas Silase Dua Varietas Jagung (Zea mays L.

    Directory of Open Access Journals (Sweden)

    La Karimuna

    2009-04-01

    Full Text Available Effects of crop arrangement and cutting on the silages quality of two varieties of maize (Zea mays L. ABSTRACT. The objective of this experiment was to study the interaction effect of varieties, spacing and cutting on the quality of silage as foodstuff. The experiment had been conducted from January to April, 2007 at the experimental Garden of Faculty of Agriculture, University of Haluoleo. This experiment was arranged in Split-Split plot design with three factors. The first factor was variety as main plot, consisting of BISI-2 variety and local variety; the second factor was space arrangement as sub plot, consisting of 60 cm x 40 cm (J1, 75 cm x 40 cm (J2, 90 cm x 40 cm (J3, the third factor was cutting period as sub plot, consisting of no cutting (Po, cutting on 40 days (P1, and cutting on 55 days (P2. So that there were 2 x 3 x 3 x 3 = 54 experimental units. Analysis of variance was applied to know the effect of treatment. If so, least significant difference (LSD 0.05 (95 % confidence level was used. Variables observed was plant growth determining silages quality, consisting of quality of crude protein, crude fiber, crude fat, and water. Results of research revealed that interaction affect of spacing and cutting periods on 40 days of BISI-2 variety gave the best yield of plant growth for plant height. While the local variety tended to adverse effect of cutting. However, the quality of silages of two varieties tended to be similar. Every crop spacing had a positive effect of cutting on 40 days. The best quality of silages of two varieties was resulted from the interaction between spacing 75 cm x 40 cm and cutting of 40 days.

  13. Hydrogen sulphide improves adaptation of Zea mays seedlings to iron deficiency.

    Science.gov (United States)

    Chen, Juan; Wu, Fei-Hua; Shang, Yu-Ting; Wang, Wen-Hua; Hu, Wen-Jun; Simon, Martin; Liu, Xiang; Shangguan, Zhou-Ping; Zheng, Hai-Lei

    2015-11-01

    Hydrogen sulphide (H2S) is emerging as a potential molecule involved in physiological regulation in plants. However, whether H2S regulates iron-shortage responses in plants is largely unknown. Here, the role of H2S in modulating iron availability in maize (Zea mays L. cv Canner) seedlings grown in iron-deficient culture solution is reported. The main results are as follows: Firstly, NaHS, a donor of H2S, completely prevented leaf interveinal chlorosis in maize seedlings grown in iron-deficient culture solution. Secondly, electron micrographs of mesophyll cells from iron-deficient maize seedlings revealed plastids with few photosynthetic lamellae and rudimentary grana. On the contrary, mesophyll chloroplasts appeared completely developed in H2S-treated maize seedlings. Thirdly, H2S treatment increased iron accumulation in maize seedlings by changing the expression levels of iron homeostasis- and sulphur metabolism-related genes. Fourthly, phytosiderophore (PS) accumulation and secretion were enhanced by H2S treatment in seedlings grown in iron-deficient solution. Indeed, the gene expression of ferric-phytosiderophore transporter (ZmYS1) was specifically induced by iron deficiency in maize leaves and roots, whereas their abundance was decreased by NaHS treatment. Lastly, H2S significantly enhanced photosynthesis through promoting the protein expression of ribulose-1,5-bisphosphate carboxylase large subunit (RuBISCO LSU) and phosphoenolpyruvate carboxylase (PEPC) and the expression of genes encoding RuBISCO large subunit (RBCL), small subunit (RBCS), D1 protein (psbA), and PEPC in maize seedlings grown in iron-deficient solution. These results indicate that H2S is closely related to iron uptake, transport, and accumulation, and consequently increases chlorophyll biosynthesis, chloroplast development, and photosynthesis in plants.

  14. Pengaruh Jarak Tanam dan Pemangkasan terhadap Kualitas Silase Dua Varietas Jagung (Zea mays L.

    Directory of Open Access Journals (Sweden)

    La Karimuna

    2009-04-01

    Full Text Available Effects of crop arrangement and cutting on the silages quality of two varieties of maize (Zea mays L. ABSTRACT. The objective of this experiment was to study the interaction effect of varieties, spacing and cutting on the quality of silage as foodstuff. The experiment had been conducted from January to April, 2007 at the experimental Garden of Faculty of Agriculture, University of Haluoleo. This experiment was arranged in Split-Split plot design with three factors. The first factor was variety as main plot, consisting of BISI-2 variety and local variety; the second factor was space arrangement as sub plot, consisting of 60 cm x 40 cm (J1, 75 cm x 40 cm (J2, 90 cm x 40 cm (J3, the third factor was cutting period as sub plot, consisting of no cutting (Po, cutting on 40 days (P1, and cutting on 55 days (P2. So that there were 2 x 3 x 3 x 3 = 54 experimental units. Analysis of variance was applied to know the effect of treatment. If so, least significant difference (LSD 0.05 (95 % confidence level was used. Variables observed was plant growth determining silages quality, consisting of quality of crude protein, crude fiber, crude fat, and water. Results of research revealed that interaction affect of spacing and cutting periods on 40 days of BISI-2 variety gave the best yield of plant growth for plant height. While the local variety tended to adverse effect of cutting. However, the quality of silages of two varieties tended to be similar. Every crop spacing had a positive effect of cutting on 40 days. The best quality of silages of two varieties was resulted from the interaction between spacing 75 cm x 40 cm and cutting of 40 days.

  15. Zea mays iRS1563: a comprehensive genome-scale metabolic reconstruction of maize metabolism.

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    Rajib Saha

    Full Text Available The scope and breadth of genome-scale metabolic reconstructions have continued to expand over the last decade. Herein, we introduce a genome-scale model for a plant with direct applications to food and bioenergy production (i.e., maize. Maize annotation is still underway, which introduces significant challenges in the association of metabolic functions to genes. The developed model is designed to meet rigorous standards on gene-protein-reaction (GPR associations, elementally and charged balanced reactions and a biomass reaction abstracting the relative contribution of all biomass constituents. The metabolic network contains 1,563 genes and 1,825 metabolites involved in 1,985 reactions from primary and secondary maize metabolism. For approximately 42% of the reactions direct literature evidence for the participation of the reaction in maize was found. As many as 445 reactions and 369 metabolites are unique to the maize model compared to the AraGEM model for A. thaliana. 674 metabolites and 893 reactions are present in Zea mays iRS1563 that are not accounted for in maize C4GEM. All reactions are elementally and charged balanced and localized into six different compartments (i.e., cytoplasm, mitochondrion, plastid, peroxisome, vacuole and extracellular. GPR associations are also established based on the functional annotation information and homology prediction accounting for monofunctional, multifunctional and multimeric proteins, isozymes and protein complexes. We describe results from performing flux balance analysis under different physiological conditions, (i.e., photosynthesis, photorespiration and respiration of a C4 plant and also explore model predictions against experimental observations for two naturally occurring mutants (i.e., bm1 and bm3. The developed model corresponds to the largest and more complete to-date effort at cataloguing metabolism for a plant species.

  16. Effect of Microbial inoculation in combating the aluminium toxicity effect on growth of Zea mays.

    Science.gov (United States)

    Arora, P; Singh, G; Tiwari, A

    2017-07-31

    The present study is aimed at improving the aluminium tolerance in maize crop employing the potential of microbial inoculants in conferring resistance to these toxicities via production of certain chelating compounds like siderophores, exopolysachharides and organic acids. Acid soils have now-a-days become one of the key factors for limiting growth of many agriculturally important crops. Aluminium  is one of the major elements present in acid soils and is mainly responsible for toxicity in the soil. This aluminium is rapidly soluble in soil water and hence absorbed by plant roots under conditions where soil pH is below 5. This toxicity leads to severe root growth inhibition, thereby limiting the production of maize crops. It was observed that use of microbial inoculums can be helpful in elimination of these toxic compounds and prevent the inhibition of root growth . It was found that the soils contaminated with aluminium toxicity decreased the root length of maize plant significantly by 65% but Bacillus and Burkholderia inoculation increased this root length significantly by 1.4- folds and 2- folds respectively thereby combating the effect of aluminium toxicity. Aluminium concentration was found maximum in roots of plants which were grown under aluminium stress condition. But this aluminium accumulation decreased ̴ 2-folds when Burkholderia was used as seed inoculants under aluminium stress conditions. Also, at 60mM aluminium accumulation, phosphorus solubilisation in roots was found to be increased upto 30% on Burkholderia inoculation. However, Bacillus inoculation didn't show any significant difference in either of the case. Thus, the inoculation of seeds with Burkholderia isolates could prove to be a boon in sequestering aluminium toxicity in Zea mays.

  17. (—) S-adenosyl-L-methionine-magnesium Protoporphyrin Methyltransferase, an Enzyme in the Biosynthetic Pathway of Chlorophyll in Zea mays 1

    Science.gov (United States)

    Radmer, Richard J.; Bogorad, Lawrence

    1967-01-01

    The enzyme (—) S-adenosyl-L-methionine-magnesium protoporphyrin methyltransferase, which catalyzes the transfer of the methyl group from (—) S-adenosyl-L-methionine to magnesium protoporphyrin to form magnesium protoporphyrin monomethyl ester, has been detected in chloroplasts isolated from Zea mays. Zinc protoporphyrin and free protoporphyrin also act as substrates in the system, although neither one is as active as magnesium protoporphyrin. The following scheme of chlorophyll synthesis in higher plants is proposed: δ-aminolevulinic acid → → → protoporphyrin → magnesium protoporphyrin → magnesium protoporphyrin monomethyl ester → → → chlorophyll a. PMID:6045301

  18. The potential of Zea mays, Commelina bengelensis, Helianthus annuus and Amaranthus hybridus for phytoremediation of waste water

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    Chacha Joseph Sarima

    2012-12-01

    Full Text Available Waste-water from domestic use and from industrial effluent burden the water systems with high levels of heavy metal hence there is need to remove these heavy metals so that the waste water can be recycled for use for household or irrigation. The present study has screened Zea mays (maize, Commelina bengelensis (wondering jew, Helianthus annuus (sunflower and Amaranthus hybridus (amaranthus for their ability to bioaccumulate Pb, Cu, Cd and Zn metals. The results obtained show that the H. annuus and C. bengelensis plant have promising potential for removal of Pb, Cu and Cd from wastewater though their ability to remove Zn from contaminated solutions is not much different from that of Z. mays and A. hybridus.

  19. Determination of genotoxic effects of boron and zinc on Zea mays using protein and random amplification of polymorphic DNA analyses.

    Science.gov (United States)

    Erturk, Filiz Aygun; Nardemir, Gokce; Hilal, A Y; Arslan, Esra; Agar, Guleray

    2015-11-01

    In this research, we aimed to determine genotoxic effects of boron (B) and zinc (Zn) on Zea mays by using total soluble protein content and random amplification of polymorphic DNA (RAPD) analyses. For the RAPD analysis, 16 RAPD primers were found to produce unique polymorphic band profiles on treated maize seedlings. With increased Zn and B concentrations, increased polymorphism rate was observed, while genomic template stability and total soluble protein content decreased. The treatment with Zn was more effective than that of B groups on the levels of total proteins. The obtained results from this study revealed that the total soluble protein levels and RAPD profiles were performed as endpoints of genotoxicity and these analyses can offer useful biomarker assays for the evaluation of genotoxic effects on Zn and B polluted plants. © The Author(s) 2013.

  20. Cytogenetics of monosomes in Zea mays. Progress report, May 16, 1980-May 15, 1981

    Energy Technology Data Exchange (ETDEWEB)

    Weber, D. F.

    1981-02-01

    Monosomics lack a pairing partner in each meiotic cell, and genes on an entire chromosome are present in the hemizygous condition. We have isolated monosomics for chromosomes 1, 2, 3, 4, 6, 7, 8, 9, and 10 in Zea mays utilizing a recently-discovered system. This is the only series of this type that has been recovered in any diploid organism. The monosomic plants are surprisingly vigorous, good cytological samples can be taken, and crosses can be made. We are isolating all possible monosomic types and characterizing them by studying: (1) the cytology of meiosis, (2) the cytological behavior of univalent chromosomes, (3) the effect of monosomy and trisomy on intergenic and intragenic recombination, (4) the frequency and types of spontaneous chromosomal aberrations arising in monosomics, (5) the effect of aneuploidy on the relative amounts of specific fatty acids in embryos, (6) monosomic mutational mapping, (7) the effect of monosomy on pollen exine morphology with the scanning electron microscope, and (8) the effect of monosomy on DIMBOA levels. We are also developing test systems utilizing maize to detect the environmental or genetic induction of non-disjunction. This study has discovered genetic factors that control the meiotic process, genetic recombination, lipid biosynthesis, and the free amino acid pool.

  1. Characteristics and functional properties of purple corn (Zea mays L. var. subnigroviolaceo

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    Jhoseline Guillén-Sánchez

    2014-09-01

    Full Text Available Zea Mays L. variety purple (purple corn is a plant native of America, which has the episperm seeds (grains and the cobs (cob in purple, which gives special characteristics to the pigments that have (between 1.5% and 6.0%, called anthocyanins, which belong to the group of flavonoids. Due to its high content of anthocyanins (cianin C3G-3-glucose as its main color and phenolic compounds act as powerful natural antioxidant and anticancer, Further having functional properties due to these bioactive compounds. The purple corn also provides significant amounts of starch, about 80% (complex carbohydrate, 10% of sugars provide sweetness, up to 11% protein, up to 2% minerals and B vitamins and ascorbic acid, concentrated in endosperm (grain free envelope. Also the nutritional value, the purple corn has a rich composition of phytochemicals, which have beneficial effects on our body, such as neutralize free radicals and act as antimutagenic. His review paper aimed to collect information on the studies undertaken to purple corn as an alternative to artificial food dyes and health benefits when included in the diet. Benefits such as cardiovascular diseases (hypertension, lowering cholesterol, fighting diabetes, being the most remarkable antioxidant action (wrinkle.

  2. Evolution of Resistance by Helicoverpa zea (Lepidoptera: Noctuidae) Infesting Insecticidal Crops in the Southern United States.

    Science.gov (United States)

    Pan, Zaiqi; Onstad, David; Crain, Philip; Crespo, Andre; Hutchison, William; Buntin, David; Porter, Pat; Catchot, Angus; Cook, Don; Pilcher, Clint; Flexner, Lindsey; Higgins, Laura

    2016-04-01

    We created a deterministic, frequency-based model of the evolution of resistance by corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), to insecticidal traits expressed in crops planted in the heterogeneous landscapes of the southern United States. The model accounts for four generations of selection by insecticidal traits each year. We used the model results to investigate the influence of three factors on insect resistance management (IRM): 1) how does adding a third insecticidal trait to both corn and cotton affect durability of the products, 2) how does unstructured corn refuge influence IRM, and 3) how do block refuges (50% compliance) and blended refuges compare with regard to IRM? When Bt cotton expresses the same number of insecticidal traits, Bt corn with three insecticidal traits provides longer durability than Bt corn with two pyramided traits. Blended refuge provides similar durability for corn products compared with the same level of required block refuge when the rate of refuge compliance by farmers is 50%. Results for Mississippi and Texas are similar, but durabilities for corn traits are surprisingly lower in Georgia, where unstructured corn refuge is the highest of the three states, but refuge for Bt cotton is the lowest of the three states. Thus, unstructured corn refuge can be valuable for IRM but its influence is determined by selection for resistance by Bt cotton.

  3. Characterization and expression of an antifungal zeamatin-like protein (Zlp) gene from Zea mays.

    Science.gov (United States)

    Malehorn, D E; Borgmeyer, J R; Smith, C E; Shah, D M

    1994-12-01

    A cDNA clone encoding a basic thaumatin-like protein of Zea mays was recovered from a mid-development seed cDNA library. The gene, Zlp, encoded a protein that was nearly identical with maize zeamatin and alpha-amylase/trypsin inhibitor. Expression of Zlp mRNA was highest in the endosperm tissue of seed 4 weeks after pollination. Expression of zeamatin-like (ZLP) protein correlated with mRNA; also, a low basal level of ZLP expression in leaf was not appreciably induced by abiotic stresses. ZLP was expressed with its own signal peptide in insect cells and in transgenic Arabidopsis and tomato plants. ZLP was secreted in all three systems, with correct processing of the signal peptide. ZLP expressed in transgenic tomato was found to be partially subjected to a proteolytic cleavage after residue 180, by an unknown mechanism, to give a "nicked" isoform of ZLP. Purified ZLP from all three sources, as well as purified "nicked" ZLP from tomato, demonstrated fungal inhibition against Candida albicans and Trichoderma reesei, with marginal inhibition observed against Alternaria solani and Neurospora crassa.

  4. Root cap removal increases root penetration resistance in maize (Zea mays L).

    Science.gov (United States)

    Iijima, Morio; Higuchi, Toshifumi; Barlow, Peter W; Bengough, A Glyn

    2003-09-01

    The root cap assists the passage of the root through soil by means of its slimy mucilage secretion and by the sloughing of its outer cells. The root penetration resistance of decapped primary roots of maize (Zea mays L. cv. Mephisto) was compared with that of intact roots in loose (dry bulk density 1.0 g cm-3; penetration resistance 0.06 MPa) and compact soil (1.4 g cm-3; penetration resistance 1.0 MPa), to evaluate the contribution of the cap to decreasing the impedance to root growth. Root elongation rate and diameter were the same for decapped and intact roots when the plants were grown in loose soil. In compacted soil, however, the elongation rate of decapped roots was only about half that of intact roots, whilst the diameter was 30% larger. Root penetration resistances of intact and decapped seminal axis were 0.31 and 0.52 MPa, respectively, when the roots were grown in compacted soil. These results indicated that the presence of a root cap alleviates much of the mechanical impedance to root penetration, and enables roots to grow faster in compacted soils.

  5. Effect of salt stress on some sweet corn (Zea mays L. var. saccharata genotypes

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    Shtereva Lydia A.

    2015-01-01

    Full Text Available An experiment was carried out hydroponically under laboratory conditions to investigate the effect of salt stress on several physiological and biochemical parameters of three sweet corn (Zea mays L. var. saccharata genotypes: lines 6-13, C-6 (pollen source and their heterotic F1 hybrid “Zaharina”. The degree of salinity tolerance among these genotypes was evaluated at three different sodium chloride (NaCl concentrations: 0 mM, 100 mM, 125 mM and 150 mM. Seed germination, plant growth and biochemical stress determining parameters such as malondialdehyde (MDA, proline content and hydrogen peroxide (H2O2 levels were compared between seedlings of lines and hybrid. The obtained results indicated that both lines and hybrid have similar responses at different salinity levels for all examined traits. All the seedlings’ growth parameters, such as germination percentage, root length, shoot length, root and shoot fresh and dry weight, decreased with increasing salinity level. MDA, proline and H2O2 increased at different saline conditions in comparison to the control. Based on the results, of the three genotypes examined, the hybrid Zaharina, followed by line C-6, was more salt-sensitive than line 6-13 in salt stress condition.

  6. Targeted mutagenesis in Zea mays using TALENs and the CRISPR/Cas system.

    Science.gov (United States)

    Liang, Zhen; Zhang, Kang; Chen, Kunling; Gao, Caixia

    2014-02-20

    Transcription activator-like effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems have emerged as powerful tools for genome editing in a variety of species. Here, we report, for the first time, targeted mutagenesis in Zea mays using TALENs and the CRISPR/Cas system. We designed five TALENs targeting 4 genes, namely ZmPDS, ZmIPK1A, ZmIPK, ZmMRP4, and obtained targeting efficiencies of up to 23.1% in protoplasts, and about 13.3% to 39.1% of the transgenic plants were somatic mutations. Also, we constructed two gRNAs targeting the ZmIPK gene in maize protoplasts, at frequencies of 16.4% and 19.1%, respectively. In addition, the CRISPR/Cas system induced targeted mutations in Z. mays protoplasts with efficiencies (13.1%) similar to those obtained with TALENs (9.1%). Our results show that both TALENs and the CRISPR/Cas system can be used for genome modification in maize.

  7. Effect of a longitudinally applied voltage upon the growth of Zea mays seedlings

    Science.gov (United States)

    Desrosiers, M. F.; Bandurski, R. S.

    1988-01-01

    The electrical parameters that affect young seedling growth were investigated. Voltages ranging from 5 to 40 volts were applied longitudinally along the mesocotyl region of 4-day old Zea mays L. (cv Silver Queen) seedlings for periods of 3 or 4 hours. It was determined that: (a) making the tips of the seedlings electrically positive relative to the base strongly inhibited shoot growth at 5 volts, whereas the reverse polarity had no effect; (b) at higher voltages, making the tip of the seedlings negative caused less growth inhibition than the reverse polarity at each voltage level; (c) the higher the applied voltage the greater the degree of inhibition; and, (d) the more growth inhibition experienced by the plants the poorer, and slower, their recovery. Previous observations of a relationship between the amount of free indole-3-acetic acid in the mesocotyl cortex and the growth rate of the mesocotyl and of gravitropism-induced movement of labeled indole-3-acetic acid from the seed to the shoot lead to the prediction of a voltage-dependent gating of the movement of indole-3-acetic acid from the stele to the cortex. This provided the basis for attempting to alter the growth rate of seedlings by means of an applied voltage.

  8. Calcium-regulated in vivo protein phosphorylation in Zea mays L. root tips

    Science.gov (United States)

    Raghothama, K. G.; Reddy, A. S.; Friedmann, M.; Poovaiah, B. W.

    1987-01-01

    Calcium dependent protein phosphorylation was studied in corn (Zea mays L.) root tips. Prior to in vivo protein phosphorylation experiments, the effect of calcium, ethyleneglycol-bis-(beta-aminoethyl ether)-N-N' -tetraacetic acid (EGTA) and calcium ionophore (A-23187) on phosphorus uptake was studied. Calcium increased phosphorus uptake, whereas EGTA and A-23187 decreased it. Consequently, phosphorus concentration in the media was adjusted so as to attain similar uptake in different treatments. Phosphoproteins were analyzed by two-dimensional gel electrophoresis. Distinct changes in phosphorylation were observed following altered calcium levels. Calcium depletion in root tips with EGTA and A-23187 decreased protein phosphorylation. However, replenishment of calcium following EGTA and ionophore pretreatment enhanced phosphorylation of proteins. Preloading of the root tips with 32P in the presence of EGTA and A-23187 followed by a ten minute calcium treatment, resulted in increased phosphorylation indicating the involvement of calcium, calcium and calmodulin-dependent kinases. Calmodulin antagonist W-7 was effective in inhibiting calcium-promoted phosphorylation. These studies suggest a physiological role for calcium-dependent phosphorylation in calcium-mediated processes in plants.

  9. Selection of inbred maize (Zea mays L.) progenies by topcrosses conducted in contrasting environments.

    Science.gov (United States)

    Rodrigues, C S; Pacheco, C A P; Guedes, M L; Pinho, R G V; Castro, C R

    2016-09-23

    The aim of this study was to identify inbred progenies of S0:1 maize (Zea mays L.) plants that were efficient at a low level of technology and responsive at a high level of technology through the use of topcrosses. Two contrasting environments were created using two levels of base fertilization and topdressing, so that the levels of nitrogen, phosphorus, and potassium were applied four times higher in one environment than in the other. We used S0:1 progenies derived from commercial hybrids in topcrosses with two testers (an elite line from the flint heterotic group and an elite line from the dent heterotic group). The progenies and three controls were evaluated in an augmented block design in Nossa Senhora das Dores, SE, Brazil in the 2010 crop season. The average grain yield in the high-technological level was 21.44% greater than that in the low-technological level. There were no changes in progeny behavior in the two technological levels for grain yield. The testers did not differ in the average grain yield of the progenies at the two technological levels. Therefore, it is possible to select progenies derived from commercial hybrids that have an efficient response to fertilization.

  10. Characterization and Fine Mapping of a Necrotic Leaf Mutant in Maize (Zea mays L.)

    Institute of Scientific and Technical Information of China (English)

    Lijing Wang; Shuai Han; Shiyi Zhong; Haizhong Wei; Yanjun Zhang; Yan Zhao; Baoshen Liu

    2013-01-01

    Maize (Zea mays L.) is a commercially important crop.Its yield can be reduced by mutations in biosynthetic and degradative pathways that cause death.In this paper,we describe the necrotic leaf (nec-t) mutant,which was obtained from an inbred line,81647.The nec-t mutant plants had yellow leaves with necrotic spots,reduced chlorophyll content,and the etiolated seedlings died under normal growth conditions.Transmission electron microscopy revealed scattered thylakoids,and reduced numbers of grana lamellae and chloroplasts per cell.Histochemical staining suggested that spot formation of nec-t leaves might be due to cell death.Genetic analysis showed that necrosis was caused by the mutation of a recessive locus.Using simple sequence repeat markers,the Nec-t gene was mapped between mmc0111 and bnlg2277 on the short arm of chromosome 2.A total of 1287 individuals with the mutant phenotype from a F2 population were used for physical mapping.The Nec-t gene was located between markers T31 and H8 within a physical region of 131.7 kb.

  11. Cloning and Functional Characterization of the Maize (Zea mays L. Carotenoid Epsilon Hydroxylase Gene.

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    Shu Chang

    Full Text Available The assignment of functions to genes in the carotenoid biosynthesis pathway is necessary to understand how the pathway is regulated and to obtain the basic information required for metabolic engineering. Few carotenoid ε-hydroxylases have been functionally characterized in plants although this would provide insight into the hydroxylation steps in the pathway. We therefore isolated mRNA from the endosperm of maize (Zea mays L., inbred line B73 and cloned a full-length cDNA encoding CYP97C19, a putative heme-containing carotenoid ε hydroxylase and member of the cytochrome P450 family. The corresponding CYP97C19 genomic locus on chromosome 1 was found to comprise a single-copy gene with nine introns. We expressed CYP97C19 cDNA under the control of the constitutive CaMV 35S promoter in the Arabidopsis thaliana lut1 knockout mutant, which lacks a functional CYP97C1 (LUT1 gene. The analysis of carotenoid levels and composition showed that lutein accumulated to high levels in the rosette leaves of the transgenic lines but not in the untransformed lut1 mutants. These results allowed the unambiguous functional annotation of maize CYP97C19 as an enzyme with strong zeinoxanthin ε-ring hydroxylation activity.

  12. New resistance genes in the Zea mays: exserohilum turcicum pathosystem

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    Juliana Bernardi Ogliari

    2005-09-01

    Full Text Available The use of monogenic race-specific resistance is widespread for the control of maize (Zea mays L. helminthosporiosis caused by Exserohilum turcicum. Inoculation of 18 Brazilian isolates of E. turcicum onto elite maize lines containing previously identified resistance genes and onto differential near-isogenic lines allowed the identification of new qualitative resistance genes. The inoculation of one selected isolate on differential near-isogenic lines, F1 generations and a BC1F1 population from the referred elite lines enabled the characterization of the resistance spectrum of three new genes, one dominant (HtP, one recessive (rt and a third with non-identified genetic action. Three physiological races of the pathogen were also identified including two with new virulence factors capable of overcoming the resistance of one of the resistance genes identified here (rt.

  13. PATOGENICIDAD BACTERIANA EN MAÍZ (ZEA MAYS

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    Rocío Pérez-y-Terrón

    2012-01-01

    Full Text Available El maíz es un grano de consumo mundial para alimento tanto humano como animal. México se encuentra en el séptimo lugar de la producción, China y Estados Unidos son los principales consumidores. Zea mays pertenece a la familia de las gramíneas y tiene producción anual. La planta se puede ver afectada por plagas principalmente de diferentes especies de insectos. Puede también desarrollar enfermedad debida a hongos y virus, así como a bacterias patogénicas. Dentro de estas la causada por organismos del género Pantoea. P. stewartii se sabe que tiene genes como cps que codifican para la producción de exopolisacarido sterwatan controlada por un mecanismo de quórum sensing, y hrp para el sistema de secreción tipo III involucrados en la patogenicidad de la bacteria.

  14. Stable isotope biogeochemistry of seabird guano fertilization: results from growth chamber studies with maize (Zea mays.

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    Paul Szpak

    Full Text Available BACKGROUND: Stable isotope analysis is being utilized with increasing regularity to examine a wide range of issues (diet, habitat use, migration in ecology, geology, archaeology, and related disciplines. A crucial component to these studies is a thorough understanding of the range and causes of baseline isotopic variation, which is relatively poorly understood for nitrogen (δ(15N. Animal excrement is known to impact plant δ(15N values, but the effects of seabird guano have not been systematically studied from an agricultural or horticultural standpoint. METHODOLOGY/PRINCIPAL FINDINGS: This paper presents isotopic (δ(13C and δ(15N and vital data for maize (Zea mays fertilized with Peruvian seabird guano under controlled conditions. The level of (15N enrichment in fertilized plants is very large, with δ(15N values ranging between 25.5 and 44.7‰ depending on the tissue and amount of fertilizer applied; comparatively, control plant δ(15N values ranged between -0.3 and 5.7‰. Intraplant and temporal variability in δ(15N values were large, particularly for the guano-fertilized plants, which can be attributed to changes in the availability of guano-derived N over time, and the reliance of stored vs. absorbed N. Plant δ(13C values were not significantly impacted by guano fertilization. High concentrations of seabird guano inhibited maize germination and maize growth. Moreover, high levels of seabird guano greatly impacted the N metabolism of the plants, resulting in significantly higher tissue N content, particularly in the stalk. CONCLUSIONS/SIGNIFICANCE: The results presented in this study demonstrate the very large impact of seabird guano on maize δ(15N values. The use of seabird guano as a fertilizer can thus be traced using stable isotope analysis in food chemistry applications (certification of organic inputs. Furthermore, the fertilization of maize with seabird guano creates an isotopic signature very similar to a high-trophic level

  15. Computer Supported Indexing: A History and Evaluation of NASA's MAI System

    Science.gov (United States)

    Silvester, June P.

    1997-01-01

    Computer supported or machine aided indexing (MAI) can be categorized in multiple ways. The system used by the National Aeronautics and Space Administration's (NASA's) Center for AeroSpace Information (CASI) is described as semantic and computational. It's based on the co-occurrence of domain-specific terminology in parts of a sentence, and the probability that an indexer will assign a particular index term when a given word or phrase is encountered in text. The NASA CASI system is run on demand by the indexer and responds in 3 to 9 seconds with a list of suggested, authorized terms. The system was originally based on a syntactic system used in the late 1970's by the Defense Technical Information Center (DTIC). The NASA mainframe-supported system consists of three components: two programs and a knowledge base (KB). The evolution of the system is described and flow charts illustrate the MAI procedures. Tests used to evaluate NASA's MAI system were limited to those that would not slow production. A very early test indicated that MAI saved about 3 minutes and provided several additional terms for each document indexed. It also was determined that time and other resources spent in careful construction of the KB pay off with high-quality output and indexer acceptance of MAI results.

  16. Battle in the New World: Helicoverpa armigera versus Helicoverpa zea (Lepidoptera: Noctuidae)

    Science.gov (United States)

    2016-01-01

    The corn earworm Helicoverpa zea (Boddie) and the old world bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) are allopatric species and occur in important agricultural crops. In maize, both species tend to infest the ear. The introduction of H. armigera in Brazil has created a new scenario, where these Helicoverpa species might cohabit and interact with one another, affecting the prevalence of each species in the agroecosystem, integrated pest management, and insect resistance management. In this study, larval occurrence and proportion of these species in maize was assessed in three regions of Brazil during three crop seasons. Interaction between the species was evaluated in interspecific and intraspecific scenarios under laboratory and field conditions. Helicoverpa zea was predominant in Rio Grande do Sul and the Planaltina, DF (central Brazil). In western Bahia, H. zea was predominant in the first collection, but approximately equal in number to H armigera in the second crop season. Both species exhibit high cannibalism/predation rates, and larval size was the primary factor for larval survival in the interaction studies. Larva of H. zea had higher survival when interacting with H. armigera, indicating that H. zea has an advantage in intraguild interactions with H. armigera in maize. Overall, the results from this study indicate that maize might play a role as a source of infestation or a sink of insecticide or Bt protein unselected H. armigera populations, depending on the H. zea:H. armigera intraguild competition and adult movement in the landscape. PMID:27907051

  17. Accumulation of 5-hydroxynorvaline in maize (Zea mays) leaves is induced by insect feeding and abiotic stress.

    Science.gov (United States)

    Yan, Jian; Lipka, Alexander E; Schmelz, Eric A; Buckler, Edward S; Jander, Georg

    2015-02-01

    Plants produce a wide variety of defensive metabolites to protect themselves against herbivores and pathogens. Non-protein amino acids, which are present in many plant species, can have a defensive function through their mis-incorporation during protein synthesis and/or inhibition of biosynthetic pathways in primary metabolism. 5-Hydroxynorvaline was identified in a targeted search for previously unknown non-protein amino acids in the leaves of maize (Zea mays) inbred line B73. Accumulation of this compound increases during herbivory by aphids (Rhopalosiphum maidis, corn leaf aphid) and caterpillars (Spodoptera exigua, beet armyworm), as well as in response to treatment with the plant signalling molecules methyl jasmonate, salicylic acid and abscisic acid. In contrast, ethylene signalling reduced 5-hydroxynorvaline abundance. Drought stress induced 5-hydroxynorvaline accumulation to a higher level than insect feeding or treatment with defence signalling molecules. In field-grown plants, the 5-hydroxynorvaline concentration was highest in above-ground vegetative tissue, but it was also detectable in roots and dry seeds. When 5-hydroxynorvaline was added to aphid artificial diet at concentrations similar to those found in maize leaves and stems, R. maidis reproduction was reduced, indicating that this maize metabolite may have a defensive function. Among 27 tested maize inbred lines there was a greater than 10-fold range in the accumulation of foliar 5-hydroxynorvaline. Genetic mapping populations derived from a subset of these inbred lines were used to map quantitative trait loci for 5-hydroxynorvaline accumulation to maize chromosomes 5 and 7.

  18. Effects on the accumulation of calcium, magnesium, iron, manganese, copper and zinc of adding the two inorganic forms of selenium to solution cultures of Zea mays.

    Science.gov (United States)

    Longchamp, M; Angeli, N; Castrec-Rouelle, M

    2016-01-01

    The addition of selenate or selenite to common fertilizers for crop production could be an effective way of producing selenium-rich food and feed. However, this would be feasible only if the increase in plant selenium (Se) content did not negatively influence the uptake of other essential elements. We therefore need to understand the interactions between Se and other major and trace elements during uptake by the plant. This study aimed to evaluate the influence of inorganic forms of Se on the accumulation of selected macronutrients (Ca and Mg) and micronutrients (Fe, Zn, Mn and Cu). Those essential elements are involved in the oxidative balance of cells. Zea mays seedlings were grown hydroponically in growth chambers in nutrient solutions to which we added 10, 50 or 1000 μg.L(-1) of selenate and/or selenite. Cation accumulation was significantly affected by the addition of 50 μg.L(-1) or 1000 μg.L(-1) Se, but not by the presence of 10 μg.L(-1) of Se in the nutrient solution. The highest concentration (1000 μg.L(-1)) of Se in the nutrient solution affected the accumulation of essential cations in Zea mays: selenate tended to increase the accumulation of Mg, Zn and Mn, whereas a selenate/selenite mixture tended to decrease the accumulation of Ca, Mg, Zn and Mn. Only Fe accumulation was unaffected by Se whatever its form or concentration. Selenium may also affect the distribution of cations on Zea mays. For example, levels of Mg and Zn translocation to the shoots were lower in the presence of selenite.

  19. Fotofestivalid Poolas : Krakov ja Lódź, mai 2009 / Marge Monko

    Index Scriptorium Estoniae

    Monko, Marge, 1976-

    2009-01-01

    Krakovi fotokuu (5.-31. mai) ja Lódźi fotofestivali (7.-31. mai) näitustest. Juudi päritolu fotograafi Weegee (sünd. 1899) näitusest, sakslase Bettina Flitneri seeriast "Boatpeople", Martin Kollari projektist "Twelve stars", Elodie Pong'i videost "I am a bomb", John Goto seeriast "John Goto's New World of Circus", Andrej Balco portreeseeriast "Doméstikas", Péter Pukluse tööst "Intimacy - no title", leeduka Petras Saulenase tööst "L'herbe est l'herbe mais ce n'est pas l'herbe", Ungari kunstnike näitusest "The Sunny Side", Oliver Kerni näitusest "The Glass Key"

  20. Fotofestivalid Poolas : Krakov ja Lódź, mai 2009 / Marge Monko

    Index Scriptorium Estoniae

    Monko, Marge, 1976-

    2009-01-01

    Krakovi fotokuu (5.-31. mai) ja Lódźi fotofestivali (7.-31. mai) näitustest. Juudi päritolu fotograafi Weegee (sünd. 1899) näitusest, sakslase Bettina Flitneri seeriast "Boatpeople", Martin Kollari projektist "Twelve stars", Elodie Pong'i videost "I am a bomb", John Goto seeriast "John Goto's New World of Circus", Andrej Balco portreeseeriast "Doméstikas", Péter Pukluse tööst "Intimacy - no title", leeduka Petras Saulenase tööst "L'herbe est l'herbe mais ce n'est pas l'herbe", Ungari kunstnike näitusest "The Sunny Side", Oliver Kerni näitusest "The Glass Key"

  1. Expression and characterization of plasma membrane aquaporins in stomatal complexes of Zea mays.

    Science.gov (United States)

    Heinen, Robert B; Bienert, Gerd Patrick; Cohen, David; Chevalier, Adrien S; Uehlein, Norbert; Hachez, Charles; Kaldenhoff, Ralf; Le Thiec, Didier; Chaumont, François

    2014-10-01

    Stomata, the microscopic pores on the surface of the aerial parts of plants, are bordered by two specialized cells, known as guard cells, which control the stomatal aperture according to endogenous and environmental signals. Like most movements occurring in plants, the opening and closing of stomata are based on hydraulic forces. During opening, the activation of plasma membrane and tonoplast transporters results in solute accumulation in the guard cells. To re-establish the perturbed osmotic equilibrium, water follows the solutes into the cells, leading to their swelling. Numerous studies have contributed to the understanding of the mechanism and regulation of stomatal movements. However, despite the importance of transmembrane water flow during this process, only a few studies have provided evidence for the involvement of water channels, called aquaporins. Here, we microdissected Zea mays stomatal complexes and showed that members of the aquaporin plasma membrane intrinsic protein (PIP) subfamily are expressed in these complexes and that their mRNA expression generally follows a diurnal pattern. The substrate specificity of two of the expressed ZmPIPs, ZmPIP1;5 and ZmPIP1;6, was investigated by heterologous expression in Xenopus oocytes and yeast cells. Our data show that both isoforms facilitate transmembrane water diffusion in the presence of the ZmPIP2;1 isoform. In addition, both display CO2 permeability comparable to that of the CO2 diffusion facilitator NtAQP1. These data indicate that ZmPIPs may have various physiological roles in stomatal complexes.

  2. Superoxide-responsive gene expression in Arabidopsis thaliana and Zea mays.

    Science.gov (United States)

    Xu, Junhuan; Tran, Thu; Padilla Marcia, Carmen S; Braun, David M; Goggin, Fiona L

    2017-08-01

    Superoxide (O2(-)) and other reactive oxygen species (ROS) are generated in response to numerous biotic and abiotic stresses. Different ROS have been reported to elicit different transcriptional responses in plants, and so ROS-responsive marker genes and promoter::reporter gene fusions have been proposed as indirect means of detecting ROS and discriminating among different species. However, further information about the specificity of transcriptional responses to O2(-) is needed in order to assess potential markers for this critical stress-responsive signaling molecule. Using qRT-PCR, the expression of 12 genes previously reported to be upregulated by O2(-) was measured in Arabidopsis thaliana plants exposed to elicitors of common stress-responsive ROS: methyl viologen (an inducer of O2(-)), rose bengal (an inducer of singlet oxygen, (1)ΔO2), and exogenous hydrogen peroxide (H2O2). Surprisingly, Zinc-Finger Protein 12 (AtZAT12), which had previously been used as a reporter for H2O2, responded more strongly to O2(-) than to H2O2; moreover, the expression of an AtZAT12 promoter-reporter fusion (AtZAT12::Luc) was enhanced by diethyldithiocarbamate, which inhibits dismutation of O2(-) to H2O2. These results suggest that AtZAT12 is transcriptionally upregulated in response to O2(-), and that AtZAT12::Luc may be a useful biosensor for detecting O2(-) generation in vivo. In addition, transcripts encoding uncoupling proteins (AtUCPs) showed selectivity for O2(-) in Arabidopsis, and an AtUCP homolog upregulated by methyl viologen was also identified in maize (Zea mays L.), indicating that there are O2(-)-responsive members of this family in monocots. These results expand our limited knowledge of ROS-responsive gene expression in monocots, as well as O2(-)-selective responses in dicots. Copyright © 2017 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

  3. Effects of Cadmium on Polar Lipid Composition and Unsaturation in Maize (Zea mays) in Hydroponic Culture

    Institute of Scientific and Technical Information of China (English)

    Radhouane Chaffai; Tinni Nouhou Seybou; Brahim Marzouk; Ezzedine El Ferjani

    2007-01-01

    This study aimed to evaluate the effect of Cd exposure (100 μmol/L) on polar lipid composition, and to examine the level of fatty acid unsaturation in maize (Zea mays L.).In roots, the level of 16:0 and monounsaturated fatty acids (16:1+18:1)decreased in phosphatidylcholine (PC) and phosphatidylethanolamine (PE).In contrast, the proportion of unsaturated 18-C fatty acid species showed an opposite response to Cd.The content, on the other hand, of PC, PE, digalactosyldiacylglycerol (DGDG), and steryl lipids increased in roots (2.9-, 1.6-, 5.3-, and 1.7-fold increase, respectively).These results suggest that a more unsaturated fatty acid composition than found in control plants with a concomitant increase in polar lipids may favor seedling growth during Cd exposure.However, the observed increase in the steryl lipid (SL) : phospholipid (PL) ratio (twofold), the decrease in monogalactosyldiacylglycerol (MGDG) : DGDG ratio, as well as the induction of lipid peroxidation in roots may represent symptoms of membrane injury.In shoots, the unsaturation level was markedly decreased in PC and phosphatidylglycerol (PG) after Cd exposure, but showed a significant increase in sulfoquinovosyldiacylglycerol (SQDG),MGDG and DGDG.The content of PG and MGDG was decreased by about 65%, while PC accumulated to higher levels (4.4-fold increase).Taken together, these changes in the polar lipid unsaturation and composition are likely to be due to alterations in the glycerolipid pathway.These results also support the idea that the increase in overall unsaturation plays some role in enabling the plant to withstand the metal exposure.

  4. Transport and metabolism of indole-3-acetyl-myo-inositol-galactoside in seedlings of Zea mays

    Science.gov (United States)

    Komoszynski, M.; Bandurski, R. S.

    1986-01-01

    Indole-3-acetyl-myo-inositol galactoside labeled with 3H in the indole and 14C in the galactose moieties was applied to kernels of 5 day old germinating seedlings of Zea mays. Indole-3-acetyl-myo-inositol galactoside was not transported into either the shoot or root tissue as the intact molecule but was instead hydrolyzed to yield [3H]indole-3-acetyl-myo-inositol and [3H]indole-3-acetic acid which were then transported to the shoot with little radioactivity going to the root. With certain assumption concerning the equilibration of applied [3H]indole-3-acetyl-myo-inositol-[U-14C]galactose with the endogenous pool, it may be concluded that indole-3-acetyl-myo-inositol galactoside in the endosperm supplies about 2 picomoles per plant per hour of indole-3-acetyl-myo-inositol and 1 picomole per plant per hour of indole-3-acetic acid to the shoot and thus is comparable to indole-3-acetyl-myo-inositol as a source of indole-acetic acid for the shoot. Quantitative estimates of the amount of galactose in the kernels suggest that [3H]indole-3-acetyl-myo-inositol-[14C]galactose is hydrolyzed after the compound leaves the endosperm but before it reaches the shoot. In addition, [3H]indole-3-acetyl-myo-inositol-[14C]galactose supplies appreciable amounts of 14C to the shoot and both 14C and 3H to an uncharacterized insoluble fraction of the endosperm.

  5. The earliest archaeological maize (Zea mays L.) from highland Mexico: New accelerator mass spectrometry dates and their implications

    OpenAIRE

    Piperno, D.R.; Flannery, K. V.

    2001-01-01

    Accelerator mass spectrometry age determinations of maize cobs (Zea mays L.) from Guilá Naquitz Cave in Oaxaca, Mexico, produced dates of 5,400 carbon-14 years before the present (about 6,250 calendar years ago), making those cobs the oldest in the Americas. Macrofossils and phytoliths characteristic of wild and domesticated Zea fruits are absent from older strata from the site, although Zea pollen has previously been identified from those levels. These results, to...

  6. Influence of Rhizophagus irregularis inoculation and phosphorus application on growth and arsenic accumulation in maize (Zea mays L.) cultivated on an arsenic-contaminated soil.

    Science.gov (United States)

    Cattani, I; Beone, G M; Gonnelli, C

    2015-05-01

    Southern Tuscany (Italy) is characterized by extensive arsenic (As) anomalies, with concentrations of up to 2000 mg kg soil(-1). Samples from the location of Scarlino, containing about 200 mg kg(-1) of As, were used to study the influence of the inoculation of an arbuscular mycorrhizal (AM) fungus (Rhizophagus irregularis, previously known as Glomus intraradices) and of phosphorus (P) application, separately and in combination, on As speciation in the rhizosphere of Zea mays on plant growth and As accumulation. Also, P distribution in plant parts was investigated. Each treatment produced a moderate rise of As(III) in the rhizosphere, increased As(III) and lowered As(V) concentration in shoots. P treatment, alone or in combination with AM, augmented the plant biomass. The treatments did not affect total As concentration in the shoots (with all the values maize cultivation on a marginal land, like the one studied.

  7. Penfigoide bolhoso no adulto mais jovem: relato de três casos

    OpenAIRE

    ZANELLA, Roberta Richter; XAVIER, Tamar Alencar; Tebcherani,Antônio José; Aoki, Valéria; Sanchez,Ana Paula Galli

    2011-01-01

    O penfigoide bolhoso é uma dermatose bolhosa autoimune subepidérmica, mais comumente observada na população idosa (acima dos 70 anos). Autoanticorpos são formados contra antígenos específicos da zona de membrana basal: BP180 e BP230 (proteínas do hemidesmossomo). Apresentamos três casos de penfigoide bolhoso, em adultos com menos de 50 anos de idade, destacan do as peculiaridades clínicas na faixa etária mais jovem.

  8. Enzymatic adaptations to arsenic-induced oxidative stress in Zea mays and genotoxic effect of arsenic in root tips of Vicia faba and Zea mays.

    Science.gov (United States)

    Duquesnoy, Isabelle; Champeau, Gabrielle Marie; Evray, Germaine; Ledoigt, Gérard; Piquet-Pissaloux, Agnès

    2010-01-01

    Agronomic plant species may display physiological and biochemical responses to oxidative stress caused by heavy metals and metalloids. Zea mays plants were grown hydroponically for eight days at different concentrations of As (0, 134 and 668 μM) and at different pH (4, 7 and 9). Metabolic variations in response to As toxicity were measured using physiological parameters and antioxidant enzymatic activities. A significant decrease in SOD activity was observed in the leaves and roots of Z. mays with the majority of As treatments. As decreased G-POX activity less in leaves than in roots. An increase in the concentration of As increased APX activity in leaves and roots, except As(V) at pH 4 and pH 9 in the leaves and As(III) at pH 9 in the roots, when there was a significant decrease in APX activity at low As concentrations. After exposure to As(V), CAT activity was the same as in the control. As(III) led to an increase in CAT activity in leaves and to a decrease in roots. With increasing concentrations of As(III), CAT activity increased in both leaves and roots whatever the pH. To obtain more detailed knowledge on the effects of arsenate and arsenite exposure on Vicia faba and Z. mays, root meristems were also examined. Roots were fed hydroponically with 134, 334, 534 and 668 μM arsenate or arsenite and 4 × 10(-3)M of maleic hydrazide as positive control, at three different pH. Physiological parameters, the mitotic index and micronuclei frequencies were evaluated in root meristems. At all three pH, the highest As(V) and As(III) concentrations induced a substantial modification in root colour, increased root thickness with stiffening, and reduced root length. High concentrations also caused a significant decrease in the mitotic index, and micronucleus chromosomic aberrations were observed in the root meristems of both species. 2010 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  9. Desfolha, população de plantas e precocidade do milho afetam a incidência e a severidade de podridões de colmo Defoliation, plant population, and earliness of maize affect the incidence and severity of stalk rots

    Directory of Open Access Journals (Sweden)

    Luiz Eduardo Bassay Blum

    2003-10-01

    Full Text Available As relações entre fonte e dreno interferem sobre a ocorrência de podridões de colmo na cultura do milho (Zea mays. O estudo foi conduzido em Lages, SC, para avaliar o efeito da desfolha, população de plantas e híbridos sobre as podridões do colmo do milho. O delineamento experimental foi de blocos ao acaso com parcelas sub-subdivididas e três repetições. Os híbridos P32R21 (superprecoce, Premium (precoce e C333B (tardio foram testados sem desfolha e com 50% de desfolha no estágio de espigamento nas populações de 25.000, 50.000, 75.000 e 100.000 plantas ha-1. Avaliaram-se a incidência e a severidade das podridões do colmo causadas por Colletotrichum graminicola, Diplodia maydis e Fusarium moniliforme. O híbrido P32R21 foi o mais afetado pelos fungos causadores de podridões. Nos híbridos P32R21 e Premium, as plantas desfolhadas foram mais severamente infectadas pelos patógenos do que as intactas. O aumento da população de plantas aumentou a intensidade (incidência ou severidade de podridões de colmo nas plantas intactas e diminuiu a ocorrência nas desfolhadas.The relationship between source and sink interferes on maize (Zea mays stalk rot occurrence. This study was conducted in Lages, SC, Brazil, to evaluate the effect of defoliation, plant population, and hybrids on the intensity (incidence or severity of maize stalk rots. The experiment was set in a randomized complete block design (three replications with a split-split-plot arrangement. The hybrids P32R21 (very early, Premium (early and C333B (late were tested without defoliation and with 50% defoliation on ear formation stage at plant populations of 25,000, 50,000, 75,000, and 100,000 plants ha-1. The incidence and severity of Colletotrichum graminicola, Diplodia maydis and Fusarium moniliforme stalk rots were evaluated. The hybrid P32R21 was the most affected by stalk rots. Defoliation enhanced rots on P32R21 and Premium. Enhancements in plant population increased

  10. Day and Night Variability of CO2 Fluxes and Priming Effects under zea Mays Measured in High Resolution

    Science.gov (United States)

    Splettstoesser, Thomas; Pausch, Johanna

    2017-04-01

    Plant induced increase of soil organic matter turnover rates contribute to carbon emissions in agricultural land use systems. In order to better understand these rhizosphere priming effects, we conducted an experiment which enabled us to monitor CO2 fluxes under Zea mays plants in high resolution. The experiment was conducted in a climate chamber where the plants were grown in tightly sealed boxes for 40 days and CO2 efflux from soil was measured twice a day. Continuous 13C-CO2 label was used to allow differentiation between plant- and soil-derived CO2.This enabled us to monitor root respiration and soil organic matter turnover in the early stages of plant growth and to highlight changes in soil CO2 emissions and priming effects between day and night. The measurements were conducted with a PICARRO G2131-I C high-precision isotopic CO2 Analyzer (PICARRO INC.) utilizing an automated valve system governed by a CR1000 data logger (Campbell Scientific). After harvest roots and shoots were analyzed for 13C content. Microbial biomass, root length density and enzymatic activities in soil were measured and linked to soil organic matter turnover rates. Results show an increased soil CO2 efflux at day time periods and an overall increase with increasing plant biomass. No difference in chloroform fumigation extractable microbial biomass has been found but a strong negative priming effect was measured in the short experimental period, suggesting that the microbes shifted to the utilization of plant exudates without actual microbial growth triggered by the new labile C input. This is coherent with the observed shift in enzyme kinetics. With this experimental setup we show that measurement of priming effects in high resolution can be achieved.

  11. Effect of phosphate solubilizing microorganisms on quantitative and qualitative characteristics of maize (Zea mays L.) under water deficit stress.

    Science.gov (United States)

    Ehteshami, S M R; Aghaalikhani, M; Khavazi, K; Chaichi, M R

    2007-10-15

    The effect of seed inoculation by phosphate solubilizing microorganisms on growth, yield and nutrient uptake of maize (Zea mays L. SC. 704) was studied in a field experiment. Positive effect on plant growth, nutrient uptake, grain yield and yield components in maize plants was recorded in the treatment receiving mixed inoculum of Glomus intraradices (AM) and Pseudomonas fluorescens (Pf). Co-inoculation treatment significantly increased grain yield, yield components, harvest index, grain N and P, soil available P, root colonization percentage and crop WUE under water deficit stress. In some of investigated characteristics under well-watered conditions, chemical fertilizer treatment was higher than double inoculated treatments, but this difference was not significant. Seed inoculation only with AM positively affected the measured parameters as amount as co-inoculated treatments. According to the results showed in contrast to the inoculated treatments with AM+Pf and AM, the application of alone Pf caused a comparatively poor response. Therefore, this microorganism needs to a complement for its activity in soil. All of measured parameters in inoculated treatments were higher than uninoculated treatments under water deficit stress conditions. Furthermore, the investigated characteristics of co-inoculated plants under severe water deficit stress conditions were significantly lower than co-inoculated plants under well-watered and moderate-stressed conditions. Therefore it could be stated, these microorganisms need more time to fix and establishing themselves in soil. The present finding showed that phosphate-solubilizing microorganisms can interact positively in promoting plant growth as well as P uptake of maize plants, leading to plant tolerance improving under water deficit stress conditions.

  12. A comparative study of Tam3 and Ac transposition in transgenic tobacco and petunia plants

    NARCIS (Netherlands)

    Haring, Michel A.; Gao, Jie; Volbeda, Tjeerd; Rommens, Caius M.T.; Nijkamp, H. John J.; Hille, Jacques

    1989-01-01

    Transposition of the Anthirrinum majus Tam3 element and the Zea mays Ac element has been monitored in petunia and tobacco plants. Plant vectors were constructed with the transposable elements cloned into the leader sequence of a marker gene. Agrobacterium tumefaciens-mediated leaf disc transformatio

  13. Plant morphology, environment, and leaf area growth in wheat and maize

    NARCIS (Netherlands)

    Bos, H.J.

    1999-01-01

    Leaf area expansion of wheat (Triticum aestivum L.) and maize (Zea mays L.) plants, as contrasting representatives of the Gramineae family, was analysed. Seven variables were identified that together completely determine leaf area expansion of the plant: leaf appearance rate per tiller, specific sit

  14. Paul ja Kristjan Raua näituse lõppemise eel / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2006-01-01

    Kumu Kunstimuuseumis kuni 8. X 2006 avatud näitusest "Ühest sajandist teise. Kristjan ja Paul Raud". Näituse ja kataloogi kujundas Tiit Jürna. 6. X toimuva konverentsi kava, esinevad Sirje Helme, Bettina Baumgärtel, Tiina Abel, Mart Kivimäe, Mai Levin, Elo-Hanna Seljamaa, Erkki Anttonen, Ülo Tedre

  15. Mai tõi uute autode müügirekordi / Erki Freiberg

    Index Scriptorium Estoniae

    Freiberg, Erki

    2005-01-01

    Mais 2005 müüdi Eestis 2290 uut sõidukit. Müüduimad margid olid sõiduautodest Toyota, Renault ja Volkswagen ning tarbesõidukeist Renault, Peugeot ja Mercedes-Benz. Diagramm: Rekordiline automüük. Vt. samas: Automüük kasvab ka naabrite juures

  16. Flöödimäng veevärgitorudel / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2006-01-01

    Concordia Klari mälestusnäitus G-galeriis 2.-21. I (kuraatorid Peeter Ulas, Maria-Kristiina Ulas) ja Draakoni galeriis 9.-28. I (kuraator Anne Untera). Mai Levinil, Anne Unteral ja Vappu Thurlow'il on valmimas Concordia Klari kohta raamat, kujundab Jüri Kass

  17. Mai tõi uute autode müügirekordi / Erki Freiberg

    Index Scriptorium Estoniae

    Freiberg, Erki

    2005-01-01

    Mais 2005 müüdi Eestis 2290 uut sõidukit. Müüduimad margid olid sõiduautodest Toyota, Renault ja Volkswagen ning tarbesõidukeist Renault, Peugeot ja Mercedes-Benz. Diagramm: Rekordiline automüük. Vt. samas: Automüük kasvab ka naabrite juures

  18. Flöödimäng veevärgitorudel / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2006-01-01

    Concordia Klari mälestusnäitus G-galeriis 2.-21. I (kuraatorid Peeter Ulas, Maria-Kristiina Ulas) ja Draakoni galeriis 9.-28. I (kuraator Anne Untera). Mai Levinil, Anne Unteral ja Vappu Thurlow'il on valmimas Concordia Klari kohta raamat, kujundab Jüri Kass

  19. Paul ja Kristjan Raua näituse lõppemise eel / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2006-01-01

    Kumu Kunstimuuseumis kuni 8. X 2006 avatud näitusest "Ühest sajandist teise. Kristjan ja Paul Raud". Näituse ja kataloogi kujundas Tiit Jürna. 6. X toimuva konverentsi kava, esinevad Sirje Helme, Bettina Baumgärtel, Tiina Abel, Mart Kivimäe, Mai Levin, Elo-Hanna Seljamaa, Erkki Anttonen, Ülo Tedre

  20. Potentially toxic elements in foodcrops: Triticum aestivum L., Zea mays L.

    Science.gov (United States)

    Bini, Claudio; Fontana, Silvia; Squizzato, Stefania; Minello, Fabiola; Fornasier, Flavio; Wahsha, Mohammad

    2013-04-01

    Soil is the basis of the ecosystems and of our system of food production. Crops can uptake heavy metals and potentially toxic elements from the soil and store them in the roots or translocate them to the aerial parts. Excessive content of these elements in edible parts can produce toxic effects and, through the food chain and food consumption, result in a potential hazard for human health. In this study soils and plants (spring wheat, Triticum aestivum L. and maize, Zea mays L.) from a tannery district in North-East Italy were analyzed to determine pedological characters, soil microbial indicators and the content of some major and micro-nutrients and potentially toxic elements (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, P, Pb, S, Zn, V). The soils of the area are moderately polluted; Cr is the most important inorganic contaminant, followed by Ni, Cu and V. Factor analysis evidenced that the contaminants are in part anthropogenic and in part geogenic. Major anthropogenic origin was detected for Cr, Ni (from industrial activities), Zn, Cu, Cd (from agriculture practices). Biological Absorption Coefficient (BAC) from soil to plant roots and Translocation factor (TF) within the plant were calculated; major nutrients (K, P, S) and some micronutrients (Cu, Zn, Mg, Mn) are easily absorbed and translocated, whilst other nutrients (Ca, Fe) and potentially toxic elements or micronutrients (Al, Cd, Cr, Ni, Pb, V) are not accumulated in the seeds of the two considered species. However, the two edible species proved differently able to absorb and translocate elements, and this suggests to consider separately every species as potential PHEs transporter to the food chain and to humans. Cr concentrations in seeds and other aerial parts (stem and leaves) of the examined plants are higher than the values found for the same species and for other cereals grown on unpolluted soils. Comparing the Cr levels in edible parts with recommended dietary intake, besides other possible Cr sources

  1. Unraveling the role of dark septate endophyte (DSE) colonizing maize (Zea mays) under cadmium stress: physiological, cytological and genic aspects.

    Science.gov (United States)

    Wang, Jun-ling; Li, Tao; Liu, Gao-yuan; Smith, Joshua M; Zhao, Zhi-wei

    2016-02-25

    A growing body of evidence suggests that plant root-associated fungi such as dark septate endophytes (DSE) can help plants overcome many biotic and abiotic stresses, of great interest is DSE-plant metal tolerance and alleviation capabilities on contaminated soils. However, the tolerance and alleviation mechanisms involved have not yet been elucidated. In the current study, the regulation and physiological response of Zea mays to its root-associated DSE, Exophiala pisciphila was analyzed under increased soil Cd stress (0, 10, 50, 100 mg kg(-1)). Under Cd stress, DSE inoculation significantly enhanced the activities of antioxidant enzymes and low-molecular weight antioxidants, while also inducing increased Cd accumulation in the cell wall and conversion of Cd into inactive forms by shoot and root specific regulation of genes related to metal uptake, translocation and chelation. Our results showed that DSE colonization resulted in a marked tolerance to Cd, with a significant decrease in cadmium phytotoxicity and a significant increase in maize growth by triggering antioxidant systems, altering metal chemical forms into inactive Cd, and repartitioning subcellular Cd into the cell wall. These results provide comprehensive evidence for the mechanisms by which DSE colonization bioaugments Cd tolerance in maize at physiological, cytological and molecular levels.

  2. The effect of triazole induced photosynthetic pigments and biochemical constituents of Zea mays L. (Maize) under drought stress

    Science.gov (United States)

    Rajasekar, Mahalingam; Rabert, Gabriel Amalan; Manivannan, Paramasivam

    2016-06-01

    In this investigation, pot culture experiment was carried out to estimate the ameliorating effect of triazole compounds, namely Triadimefon (TDM), Tebuconazole (TBZ), and Propiconazole (PCZ) on drought stress, photosynthetic pigments, and biochemical constituents of Zea mays L. (Maize). From 30 days after sowing (DAS), the plants were subjected to 4 days interval drought (DID) stress and drought with TDM at 15 mg l-1, TBZ at 10 mg l-1, and PCZ at 15 mg l-1. Irrigation at 1-day interval was kept as control. Irrigation performed on alternative day. The plant samples were collected on 40, 50, and 60 DAS and separated into root, stem, and leaf for estimating the photosynthetic pigments and biochemical constituents. Drought and drought with triazole compounds treatment increased the biochemical glycine betaine content, whereas the protein and the pigments contents chlorophyll-a, chlorophyll-b, total chlorophyll, carotenoid, and anthocyanin decreased when compared to control. The triazole treatment mitigated the adverse effects of drought stress by increasing the biochemical potentials and paved the way to overcome drought stress in corn plant.

  3. Comparative impact of genetically modified and non modified maize (Zea mays L.) on succeeding crop and associated weed.

    Science.gov (United States)

    Ibrahim, Muhammad; Ahmed, Naseer; Ullah, Faizan; Shinwari, Zabta Khan; Bano, Asghari

    2016-04-01

    This research work documents the comparative impact of genetically modified (GM) (insect resistance) and non modified maize (Zea mays L.) on growth and germination of succeeding crop wheat (Triticum aestivum L.) and associated weed (Avena fatua L.). The aqueous extracts of both the GM and non-GM maize exhibited higher phenolic content than that of methanolic extracts. Germination percentage and germination index of wheat was significantly decreased by GM methanolic extract (10%) as well as that of non-GM maize at 3% aqueous extract. Similarly germination percentage of weed (Avena fatua L.) was significantly reduced by application of 3% and 5% methanolic GM extracts. All extracts of GM maize showed non-significant effect on the number of roots, root length and shoot length per plant but 5% and 10% methanolic extracts of non-GM maize significantly increased the number of roots per plant of wheat seedling. Similarly, 10% methanolic extract of GM maize significantly increased the number of roots per plant of weed seedling. Methanolic extracts of GM and non-GM maize (3% and 5%) significantly decreased the protease activity in wheat as compared to untreated control.

  4. Unraveling the role of dark septate endophyte (DSE) colonizing maize (Zea mays) under cadmium stress: physiological, cytological and genic aspects

    Science.gov (United States)

    Wang, Jun-ling; Li, Tao; Liu, Gao-yuan; Smith, Joshua M.; Zhao, Zhi-wei

    2016-01-01

    A growing body of evidence suggests that plant root-associated fungi such as dark septate endophytes (DSE) can help plants overcome many biotic and abiotic stresses, of great interest is DSE-plant metal tolerance and alleviation capabilities on contaminated soils. However, the tolerance and alleviation mechanisms involved have not yet been elucidated. In the current study, the regulation and physiological response of Zea mays to its root-associated DSE, Exophiala pisciphila was analyzed under increased soil Cd stress (0, 10, 50, 100 mg kg−1). Under Cd stress, DSE inoculation significantly enhanced the activities of antioxidant enzymes and low-molecular weight antioxidants, while also inducing increased Cd accumulation in the cell wall and conversion of Cd into inactive forms by shoot and root specific regulation of genes related to metal uptake, translocation and chelation. Our results showed that DSE colonization resulted in a marked tolerance to Cd, with a significant decrease in cadmium phytotoxicity and a significant increase in maize growth by triggering antioxidant systems, altering metal chemical forms into inactive Cd, and repartitioning subcellular Cd into the cell wall. These results provide comprehensive evidence for the mechanisms by which DSE colonization bioaugments Cd tolerance in maize at physiological, cytological and molecular levels. PMID:26911444

  5. Reproduction of the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) B biotype in maize fields (Zea mays L.) in Brazil.

    Science.gov (United States)

    Quintela, Eliane D; Abreu, Aluana G; Lima, Julyana F Dos S; Mascarin, Gabriel M; Santos, Jardel B Dos; Brown, Judith K

    2016-11-01

    Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) was observed to have completed its reproductive cycle from the egg to the adult on maize (Zea mays L.). Field and screenhouse studies were carried out to investigate the durability of this putative and unprecedented adaptation to a grass host. Analysis of the mitochondrial COI gene sequence identified the maize-associated B. tabaci as the exotic B biotype (major clade North Africa-Mediterranean-Middle East). Results showed that whiteflies migrated from soybean crops and successfully established in maize plants. Females exhibited a preference for oviposition primarily on the first and second leaves of maize, but were also able to colonise developing leaves. A high, natural infestation on maize (193.3 individuals, all developmental stages) was observed within a 7.1 cm(2) designated 'observation area'. Whiteflies collected from naturally infested maize leaves and allowed to oviposit on maize seedlings grown in a screenhouse developed from egg to adulthood in 28.6 ± 0.2 days. This is the first report of the B biotype completing its development on maize plants. This surprising anomaly indicates that the B biotype is capable of adapting to monocotyledonous host plants, and importantly, broadens the host range to include at least one species in the Poaceae. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. Effect of Soil Aging on the Phytoremediation Potential of Zea mays in Chromium and Benzo[a]Pyrene Contaminated Soils.

    Science.gov (United States)

    Chigbo, Chibuike

    2015-06-01

    This study compared the phytoremediation potential of Zea mays in soil either aged or freshly amended with chromium (Cr) and benzo[a]pyrene (B[a]P). Z. mays showed increased shoot biomass in aged soils than in freshly spiked soils. The shoot biomass in contaminated soils increased by over 50% in aged soil when compared to freshly amended soils, and over 29% more Cr was accumulated in the shoot of Z. mays in aged soil than in freshly amended soil. Planting Z. mays in aged soil helped in the dissipation of more than 31% B[a]P than in freshly spiked soil, but in the absence of plants, there seemed to be no difference between the dissipation rates of B[a]P in freshly and aged co-contaminated soil. Z. mays seemed to enhance the simultaneous removal of Cr and B[a]P in aged soil than in freshly spiked soil and hence can be a good plant choice for phytoremediation of co-contaminated soils.

  7. Global and grain-specific accumulation of glycoside hydrolase family 10 xylanases in transgenic maize (Zea mays).

    Science.gov (United States)

    Gray, Benjamin N; Bougri, Oleg; Carlson, Alvar R; Meissner, Judy; Pan, Shihao; Parker, Matthew H; Zhang, Dongcheng; Samoylov, Vladimir; Ekborg, Nathan A; Michael Raab, R

    2011-12-01

    In planta expression of cell wall degrading enzymes is a promising approach for developing optimized biomass feedstocks that enable low-cost cellulosic biofuels production. Transgenic plants could serve as either an enzyme source for the hydrolysis of pretreated biomass or as the primary biomass feedstock in an autohydrolysis process. In this study, two xylanase genes, Bacillus sp. NG-27 bsx and Clostridium stercorarium xynB, were expressed in maize (Zea mays) under the control of two different promoters. Severe phenotypic effects were associated with xylanase accumulation in maize, including stunted plants and sterile grains. Global expression of these xylanases from the rice ubiquitin 3 promoter (rubi3) resulted in enzyme accumulation of approximately 0.01 mg enzyme per gram dry weight, or approximately 0.1% of total soluble protein (TSP). Grain-specific expression of these enzymes from the rice glutelin 4 promoter (GluB-4) resulted in higher-level accumulation of active enzyme, with BSX and XynB accumulating up to 4.0% TSP and 16.4% TSP, respectively, in shriveled grains from selected T0 plants. These results demonstrate the potential utility of the GluB-4 promoter for biotechnological applications. The phenotypic effects of xylanase expression in maize presented here demonstrate the difficulties of hemicellulase expression in an important crop for cellulosic biofuels production. Potential alternate approaches to achieve xylanase accumulation in planta without the accompanying negative phenotypes are discussed.

  8. Unraveling the role of dark septate endophyte (DSE) colonizing maize (Zea mays) under cadmium stress: physiological, cytological and genic aspects

    Science.gov (United States)

    Wang, Jun-Ling; Li, Tao; Liu, Gao-Yuan; Smith, Joshua M.; Zhao, Zhi-Wei

    2016-02-01

    A growing body of evidence suggests that plant root-associated fungi such as dark septate endophytes (DSE) can help plants overcome many biotic and abiotic stresses, of great interest is DSE-plant metal tolerance and alleviation capabilities on contaminated soils. However, the tolerance and alleviation mechanisms involved have not yet been elucidated. In the current study, the regulation and physiological response of Zea mays to its root-associated DSE, Exophiala pisciphila was analyzed under increased soil Cd stress (0, 10, 50, 100 mg kg-1). Under Cd stress, DSE inoculation significantly enhanced the activities of antioxidant enzymes and low-molecular weight antioxidants, while also inducing increased Cd accumulation in the cell wall and conversion of Cd into inactive forms by shoot and root specific regulation of genes related to metal uptake, translocation and chelation. Our results showed that DSE colonization resulted in a marked tolerance to Cd, with a significant decrease in cadmium phytotoxicity and a significant increase in maize growth by triggering antioxidant systems, altering metal chemical forms into inactive Cd, and repartitioning subcellular Cd into the cell wall. These results provide comprehensive evidence for the mechanisms by which DSE colonization bioaugments Cd tolerance in maize at physiological, cytological and molecular levels.

  9. Extração de corantes de milho (Zea mays L. Extraction of corn colorants (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Felix Martin Cabajal Gamarra

    2009-03-01

    Full Text Available Os corantes naturais foram amplamente utilizados de forma artesanal até antes do surgimento dos corantes sintéticos. O estudo e uso dos corantes naturais voltaram a ter importância nestes últimos anos devido aos questionamentos dos organismos internacionais da saúde e dos consumidores pelo uso indiscriminado dos corantes sintéticos, ligados ao desenvolvimento de doenças degenerativas e ao impacto ambiental. O corante extraído do milho roxo (Zea mays L. tem sido utilizado ao longo da história pela civilização Inca na preparação de alimentos e no tingimento de fibras têxteis. Neste trabalho, os pigmentos do grupo das antocianinas foram extraídos das variedades de milho roxo e do milho vermelho (Z. mays L. e depois foram caracterizados. Três métodos de extração foram utilizados: imersão, lixiviação com algumas modificações e extração supercrítica (ESC. O melhor método para extração foi o da lixiviação que alcançou 88% (m/m de rendimento, em função da massa do corante extraído e da matéria-prima. Também utilizando a lixiviação modificada, foi possível concentrar em 3% os compostos acilados, assim como recuperar 85% dos solventes utilizados. Um indicador de pH foi obtido pela fixação das antocianinas num papel de filtro, com base na estabilidade das antocianinas, ferramenta que pode ser utilizada em laboratórios de ensino de química.Natural colorants were craftly made and widely used before the discovery of the synthetic colorants. The study and the use of natural colorants have become important again in the last few years due to questions raised by the international health organizations and consumers related to the indiscriminate use of synthetic colorants which were linked to the development of degenerative illnesses and environmental impact. The colorant extracted from purple corn (Zea Mays L. was used by the Inca civilization to prepare food and to dye textile fibers. In this work, pigments from the

  10. Impacts of industrial waste resources on maize (Zea mays L.) growth, yield, nutrients uptake and soil properties.

    Science.gov (United States)

    Singh, Satnam; Young, Li-Sen; Shen, Fo-Ting; Young, Chiu-Chung

    2014-10-01

    Discharging untreated highly acidic (pH10.0) paper-mill wastewater (PW) causes environmental pollution. When acidity of MW neutralized (pH 6.5±0.1) with PW and lime (treatments represented as MW+PW and MW+Lime), then MW may be utilized as a potential source of nutrients and organic carbon for sustainable food production. Objectives of this study were to compare the effects of PW and lime neutralized MW and chemical fertilizers on maize (Zea mays L. cv. Snow Jean) plant growth, yield, nutrients uptake, soil organic matter and humic substances. The field experiment was carried out on maize using MW at 6000 L ha(-1). Impacts of the MW application on maize crop and soil properties were evaluated at different stages. At harvest, plant height, and plant N and K uptake were higher in MW treatment. Leaf area index at 60 days after sowing, plant dry matter accumulation at harvest, and kernels ear(-1) and 100-kernel weight were higher in MW+Lime treatment. Kernel N, P, K, Mn, Fe and Zn, and plant Zn uptake were highest in MW+Lime. Plant Fe uptake, and soil organic matter and humic substances were highest in MW+PW. The MW+PW and MW+Lime treatments exhibited comparable results with chemically fertilized treatment. The MW acidity neutralized with lime showed positive impacts on growth, yield and nutrients uptake; nevertheless, when MW pH neutralized with PW has an additional benefit on increase in soil organic matter and humic substances.

  11. Transcriptional profiling of Zea mays roots reveals roles for jasmonic acid and terpenoids in resistance against Phytophthora cinnamomi.

    Science.gov (United States)

    Allardyce, Jane Alisa; Rookes, James Edward; Hussain, Hashmath Inayath; Cahill, David Miles

    2013-06-01

    Phytophthora cinnamomi is a soil-borne plant pathogen that has caused widespread damage to vulnerable native ecosystems and agriculture systems across the world and shows no sign of abating. Management of the pathogen in the natural environment is difficult and the options are limited. In order to discover more about how resistant plants are able to defend themselves against this generalist pathogen, a microarray study of plant gene expression following root inoculation with P. cinnamomi was undertaken. Zea mays was used as a resistant model plant, and microarray analysis was conducted using the Affymetrix GeneChip Maize Genome Array on root samples collected at 6- and 24-h post-inoculation. Over 300 genes were differentially expressed in inoculated roots compared with controls across the two time points. Following Gene Ontology enrichment analysis and REVIGO visualisation of the up-regulated genes, many were implicated in plant defence responses to biotic stress. Genes that were up-regulated included those involved in phytoalexin biosynthesis and jasmonic acid/ethylene biosynthesis and other defence-related genes including those encoding glutathione S-transferases and serine-protease inhibitors. Of particular interest was the identification of the two most highly up-regulated genes, terpene synthase11 (Tps11) and kaurene synthase2 (An2), which are both involved in production of terpenoid phytoalexins. This is the first study that has investigated gene expression at a global level in roots in response to P. cinnamomi in a model plant species and provides valuable insights into the mechanisms involved in defence.

  12. Ontogeny of the sheathing leaf base in maize (Zea mays).

    Science.gov (United States)

    Johnston, Robyn; Leiboff, Samuel; Scanlon, Michael J

    2015-01-01

    Leaves develop from the shoot apical meristem (SAM) via recruitment of leaf founder cells. Unlike eudicots, most monocot leaves display parallel venation and sheathing bases wherein the margins overlap the stem. Here we utilized computed tomography (CT) imaging, localization of PIN-FORMED1 (PIN1) auxin transport proteins, and in situ hybridization of leaf developmental transcripts to analyze the ontogeny of monocot leaf morphology in maize (Zea mays). CT imaging of whole-mounted shoot apices illustrates the plastochron-specific stages during initiation of the basal sheath margins from the tubular disc of insertion (DOI). PIN1 localizations identify basipetal auxin transport in the SAM L1 layer at the site of leaf initiation, a process that continues reiteratively during later recruitment of lateral leaf domains. Refinement of these auxin transport domains results in multiple, parallel provascular strands within the initiating primordium. By contrast, auxin is transported from the L2 toward the L1 at the developing margins of the leaf sheath. Transcripts involved in organ boundary formation and dorsiventral patterning accumulate within the DOI, preceding the outgrowth of the overlapping margins of the sheathing leaf base. We suggest a model wherein sheathing bases and parallel veins are both patterned via the extended recruitment of lateral maize leaf domains from the SAM.

  13. Genome-wide comparative in silico analysis of the RNA helicase gene family in Zea mays and Glycine max: a comparison with Arabidopsis and Oryza sativa.

    Science.gov (United States)

    Xu, Ruirui; Zhang, Shizhong; Huang, Jinguang; Zheng, Chengchao

    2013-01-01

    RNA helicases are enzymes that are thought to unwind double-stranded RNA molecules in an energy-dependent fashion through the hydrolysis of NTP. RNA helicases are associated with all processes involving RNA molecules, including nuclear transcription, editing, splicing, ribosome biogenesis, RNA export, and organelle gene expression. The involvement of RNA helicase in response to stress and in plant growth and development has been reported previously. While their importance in Arabidopsis and Oryza sativa has been partially studied, the function of RNA helicase proteins is poorly understood in Zea mays and Glycine max. In this study, we identified a total of RNA helicase genes in Arabidopsis and other crop species genome by genome-wide comparative in silico analysis. We classified the RNA helicase genes into three subfamilies according to the structural features of the motif II region, such as DEAD-box, DEAH-box and DExD/H-box, and different species showed different patterns of alternative splicing. Secondly, chromosome location analysis showed that the RNA helicase protein genes were distributed across all chromosomes with different densities in the four species. Thirdly, phylogenetic tree analyses identified the relevant homologs of DEAD-box, DEAH-box and DExD/H-box RNA helicase proteins in each of the four species. Fourthly, microarray expression data showed that many of these predicted RNA helicase genes were expressed in different developmental stages and different tissues under normal growth conditions. Finally, real-time quantitative PCR analysis showed that the expression levels of 10 genes in Arabidopsis and 13 genes in Zea mays were in close agreement with the microarray expression data. To our knowledge, this is the first report of a comparative genome-wide analysis of the RNA helicase gene family in Arabidopsis, Oryza sativa, Zea mays and Glycine max. This study provides valuable information for understanding the classification and putative functions of

  14. O Programa Mais Educação do governo federal e sua versão em Duque de Caxias: o Programa Mais Escola

    Directory of Open Access Journals (Sweden)

    Sheila Cristina Monteiro Matos

    2011-01-01

    Full Text Available Este artigo tem como objetivo apresentar o Programa Mais Educação do governo federal e o Programa Mais Escola, de Duque de Caxias-RJ. O estudo consolidou-se por meio de uma análise documental. As considerações finais apontam que a implantação e a operacionalização destes Programas ainda são recentes e que ainda há impasses e desafios no tocante aos planejamentos e à operacionalização dos macrocampos do saber. Assim, discutir e problematizar sobre tais ampliações dos espaços educativos, levando em consideração que a escola seja central no processo de articulação dos planejamentos, deve ser condição sine qua num para continuar com as parcerias estabelecidas entre a escola e outros espaços educativos.

  15. Quem são as mulheres que amamentam por 2 anos ou mais?

    Directory of Open Access Journals (Sweden)

    Elisa Justo Martins

    2012-02-01

    Full Text Available OBJETIVO: Identificar fatores associados à manutenção do aleitamento materno por 2 anos ou mais. MÉTODOS: Estudo de coorte que acompanhou 151 crianças selecionadas no Hospital de Clínicas de Porto Alegre, do nascimento até a idade de 3 a 5 anos. As mães foram entrevistadas pessoalmente na maternidade, aos 7 e 30 dias após o parto, e quando as crianças tinham entre 3 e 5 anos. As entrevistas aos 60, 120 e 180 dias de vida da criança foram feitas por contato telefônico, sempre que possível. Para testar as associações entre o desfecho (aleitamento materno por 2 anos ou mais e as variáveis explicativas, utilizou-se regressão de Poisson seguindo modelo hierárquico. RESULTADOS: Mostraram-se associados de forma positiva, com o desfecho: permanência da mãe em casa com a criança nos primeiros 6 meses de vida [risco relativo (RR = 2,13; intervalo de confiança de 95% (IC95% 1,12-4,05]; não uso de chupeta (RR = 2,45; IC95% 1,58-3,81; e introdução mais tardia de água e/ou chás e de outros leites na alimentação da criança. Para cada dia a mais sem a introdução desses líquidos, aumentava a probabilidade de a criança ser amamentada por 2 anos ou mais em 0,5% e 0,1%, respectivamente. Coabitação com o pai da criança mostrou associação negativa com o desfecho (RR = 0,61; IC95% 0,37-0,99. CONCLUSÃO: Mãe permanecer em casa com a criança nos primeiros 6 meses de vida, não coabitar com companheiro, não oferecer chupeta e postergar a introdução de água e/ou chás e outros leites na alimentação das crianças são características e comportamentos associados com a manutenção da amamentação por 2 anos ou mais.

  16. Human Health Impact of Fluoride in Groundwater in the Chiang Mai Basin

    Science.gov (United States)

    Matsui, Y.; Takizawa, S.; Wattanachira, S.; Wongrueng, A.; Ibaraki, M.

    2005-12-01

    Chiang Mai Basin, in Northern Thailand, is known as a fluorotic area. Groundwater of the Chiang Mai Basin has been gradually replaced by contaminated surface water since the 1980's. People have been exposed to fluoride contaminated groundwater since that time. As a result, harmful health effects on dental and skeletal growth were observed in the 90's. These include dental and skeletal fluorosis. Dental fluorosis is characterized by yellow or white spots on teeth and pitting or mottled enamel, consequently causing the teeth to look unsightly. Skeletal fluorosis leads to changes in bone structure, making them extremely weak and brittle. The most severe form of this is known as ``crippling skeletal fluorosis,'' a condition that can cause immobility, muscle wasting, and neurological problems related to spinal cord compression. This study focuses on the problematic issue of the Chiang Mai Basin's groundwater from the viewpoint of fluoride occurrence and current health impacts. Chiang Mai and Lamphun Provinces comprise the Chiang Mai Basin. Fluoride rich granites or fluorite deposits are scattered across the mountainside of the Lamphun Province. Tropical savanna climate conditions with seasonal monsoons bring more than 1,000 mm of annual precipitation, which can prompt weathering of minerals containing fluoride. The Ping River dominates the Basin, and the main eastern tributary of the Ping River runs through the Lamphun Province. The Basin has geological units composed of lower semi-consolidated Tertiary fluvial and upper unconsolidated Quaternary alluvium deposits. The main aquifers are in the upper unconsolidated unit. High fluoride concentrations tend to be observed in the aquifer located in lower part of this unconsolidated unit. We have been investigating two areas in the Basin. These two locations are similar with respect to geological and hydrological settings. However, one area in which groundwater is Ca-bicarbonate dominant has a low fluoride occurrence

  17. Optimum prediction of three-way crosses from single crosses in forage maize (Zea mays L.).

    Science.gov (United States)

    Melchinger, A E; Geiger, H H; Seitz, G; Schmidt, G A

    1987-07-01

    Three-way cross means were predicted with formulae involving linear functions of general (GCA) and specific combining ability (SCA) effects estimated from single-cross factorials between genetically divergent populations. Data from an experiment with 66 single-cross and 66 three-way cross forage maize (Zea mays L.) hybrids was used for comparing the prediction formulae. The genotypic correlation (r) between observed and predicted three-way crosses increased with increasing χ, the weighting factor of SCA effects, for plant height and ear dry matter (DM) content. It displayed slightly convex curves for total and stover DM yield, ear percentage, and metabolizable energy content of stover. For Jenkins' method B, r was considerably less than 1.0 for all traits, indicating the presence of epistasis. The square root of heritability (hĜ) of the predicted means decreased with increasing χ, the reduction being small with a greater number of test environments. Using the product r·hĜ as a criterion of efficiency, none of the prediction methods was consistently superior and the differences among them were rather small (< 7.5%) for all traits, irrespective of the number of test environments. We recommend evaluating the GCA of a greater number of lines from each parent population in testcrosses with a small number of elite lines from the opposite population. All possible three-way or double crosses between both sets of lines should be predicted by Jenkins's method C. This procedure allows one to select with a higher intensity among the predicted hybrids and thus should increase the genetic gain.

  18. Evaluating Corn (Zea Mays L.) N Variability Via Remote Sensed Data

    Science.gov (United States)

    Sullivan, D. G.; Shaw, J. N.; Mask, P. L.; Rickman, D.; Luvall, J.; Wersinger, J. M.

    2003-01-01

    Transformations and losses of nitrogen (N) throughout the growing season can be costly. Methods in place to improve N management and facilitate split N applications during the growing season can be time consuming and logistically difficult. Remote sensing (RS) may be a method to rapidly assess temporal changes in crop N status and promote more efficient N management. This study was designed to evaluate the ability of three different RS platforms to predict N variability in corn (Zea mays L.) leaves during vegetative and early reproductive growth stages. Plots (15 x 15m) were established in the Coastal Plain (CP) and Appalachian Plateau (AP) physiographic regions each spring from 2000 to 2002 in a completely randomized design. Treatments consisted of four N rates (0, 56, 112, and 168 kg N/ha) applied as ammonium nitrate (NH4N03) replicated four time. Spectral measurements were acquired via spectroradiometer (lambda = 350 - 1050 nm), Airborne Terrestrial Applications Sensor (ATLAS) (lambda = 400 - 12,500 nm), and the IKONOS satellite (lambda = 450 - 900 nm). Spectroradiometer data were collected on a biweekly basis from V4 through R1. Due to the nature of - satellite and aircraft acquisitions, these data were acquired per availability. Chlorophyll meter (SPAD) and tissue N were collected as ancillary data along with each RS acquisition. Results showed vegetation indices derived from hand-held spectroradiometer measurements as early as V6-V8 were linearly related to yield and tissue N content. ATLAS data was correlated with tissue N at the AP site during the V6 stage (r2 = 0.66), but no significant relationships were observed at the CP site. No significant relationships were observed between plant N and IKONOS imagery. Using a combination of the greenness vegetation index (GNDVI) and the normalized difference vegetation index (NDVI), RS data acquired via ATLAS and the spectroradiometer could be used to evaluate tissue N variability and estimate corn yield variability

  19. Proliferation of maize (Zea mays L.) roots in response to localized supply of nitrate

    Science.gov (United States)

    Granato, T. C.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

    1989-01-01

    Maize (Zea mays L.) plants with two primary nodal root axes were grown for 8 d in flowing nutrient culture with each axis independently supplied with NO3-. Dry matter accumulation by roots was similar whether 1.0 mol m-3 NO3- was supplied to one or both axes. When NO3- was supplied to only one axis, however, accumulation of dry matter within the root system was significantly greater in the axis supplied with NO3-. The increased dry matter accumulation by the +N-treated axis was attributable entirely to increased density and growth of lateral branches and not to a difference in growth of the primary axis. Proliferation of lateral branches for the +N axis was associated with the capacity for in situ reduction and utilization of a portion of the absorbed NO3-, especially in the apical region where lateral primordia are initiated. Although reduced nitrogen was translocated to the -N axis, concentrations in the -N axis remained significantly lower than in the +N axis. The concentration of reduced nitrogen, as well as in vitro NO3- reductase activity, was greater in apical than in more basal regions of the +N axis. The enhanced proliferation of lateral branches in the +N axis was accompanied by an increase in total respiration rate of the axis. Part of the increased respiration was attributable to increased mass of roots. The specific respiration rate (micromoles CO2 evolved per hour per gram root dry weight) was also greater for the +N than for the -N axis. If respiration rate is taken as representative of sink demand, stimulation of initiation and growth of laterals by in situ utilization of a localized exogenous supply of NO3- establishes an increased sink demand through enhanced metabolic activity and the increased partitioning of assimilates to the +N axis responds to the difference in sink demand between +N and -N axes.

  20. Genetic and cellular analysis of cross-incompatibility in Zea mays.

    Science.gov (United States)

    Lu, Yongxian; Kermicle, Jerry L; Evans, Matthew M S

    2014-03-01

    Three genetic systems conferring cross-incompatibility have been described in Zea mays: Teosinte crossing barrier1-strong (Tcb1-s) found in teosinte, and Gametophyte factor1-strong (Ga1-s) and Ga2-s found in maize and teosinte. The reproductive barrier between maize and some weedy teosintes is controlled by the Tcb1-s locus. Multi-generation inheritance experiments on two independent Tcb1-s lineages show that the Tcb1-s barrier is unstable in some maize lines. Reciprocal crosses between Tcb1-s tester plants and three recombinants in the Tcb1-s mapping region demonstrate that the Tcb1-s haplotype contains separable male and female components. In vivo assays of the dynamics of pollen tube growth and pollen tube morphology during rejection of incompatible pollen in silks carrying the Tcb1-s, Ga1-s, or Ga2-s barriers showed that, in all three, pollen tube growth is slower than in compatible crosses at early stages and had ceased by 24 h after pollination. In all three crossing barrier systems, incompatible pollen tubes have clustered callose plugs in contrast to pollen tubes of compatible crosses. Incompatible pollen tubes growing in the Tcb1-s, Ga1-s, and Ga2-s silks have different morphologies: straight, curved, and kinked, respectively. The distinct morphologies suggest that these crossing barriers block incompatible pollen through different mechanisms. This study lays the foundation for cloning the Tcb1 genes and provides clues about the cellular mechanisms involved in pollen rejection in the Tcb1-s, Ga1-s, and Ga2-s crossing barriers.

  1. Heavy metal stress detection and monitoring via LED-induced chlorophyll fluorescence analysis of Zea mays L. seedlings aimed at polluted soil phytoremediation

    Science.gov (United States)

    Gouveia-Neto, Artur S.; Silva, Elias A., Jr.; da Silva, Airon José; do Nascimento, Clístenes W. A.

    2012-03-01

    Chlorophyll fluorescence spectroscopy is employed to detect and study the time evolution of metal stress of Zea mays L. seedlings aiming polluted soil phytoremediation. The chlorophyll fluorescence spectra of intact leaves are analyzed using 405 nm LED excitation. Red (Fr) and far-red (FFr) emissions around 685 nm and 735 nm, respectively, are examined as a function of the heavy metal concentration. The fluorescence ratio Fr/FFr was employed to monitor the effect of heavy metal upon the physiological state of the plants before signs of visual stress became apparent. The chlorophyll fluorescence analysis permitted detection and evaluation of the damage caused by heavy metal soil contamination in the early stages of the plants growing process, which is not feasible using conventional in vitro spectral analysis.

  2. Välis- ja kodueesti kunst kui tervik : sõnum Torontost / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2003-01-01

    30. X Tartu Kunstimajas Osvald Timmase näitusel kunstniku loomingule pühendatud õhtust, kus esinesid Mai Levin ja kunstniku vend Evald Timmas, näidati slaide ning Ain Habichti tehtud koduvideosid O. Timmasest ja Abel Leest. A. Lee ja O. Timmas on olnud 1952. a. Torontos loodud Colour and Form Society presidendid. Väliseesti kunsti tuleks käsitleda koos kodueesti kunstiga

  3. Välis- ja kodueesti kunst kui tervik : sõnum Torontost / Mai Levin

    Index Scriptorium Estoniae

    Levin, Mai, 1942-

    2003-01-01

    30. X Tartu Kunstimajas Osvald Timmase näitusel kunstniku loomingule pühendatud õhtust, kus esinesid Mai Levin ja kunstniku vend Evald Timmas, näidati slaide ning Ain Habichti tehtud koduvideosid O. Timmasest ja Abel Leest. A. Lee ja O. Timmas on olnud 1952. a. Torontos loodud Colour and Form Society presidendid. Väliseesti kunsti tuleks käsitleda koos kodueesti kunstiga

  4. Consultoria Interna: inspirando-se em Argyris para uma ação mais eficaz

    National Research Council Canada - National Science Library

    Ana Lucia Neves Moura; Marcos Gilson Gomes Feitosa; Bruno Campello de Souza

    2009-01-01

    ...); e Maus conselhos, uma armadilha gerencial (2005), este ensaio teórico busca destacar contribuições valiosas que podem ajudar o consultor interno a superar os conflitos que caracterizam a sua atividade e a ter uma ação mais eficaz, criando um ambiente que favoreça o respeito, a confiança, a participação e a sinceridade, condições para gerar maior autonomia do cliente.

  5. Phytoremediation for co-contaminated soils of chromium and benzo[a]pyrene using Zea mays L.

    Science.gov (United States)

    Chigbo, Chibuike; Batty, Lesley

    2014-02-01

    A greenhouse experiment was carried out to investigate the single effect of benzo[a]pyrene (B[a]P) or chromium (Cr) and the joint effect of Cr-B[a]P on the growth of Zea mays, its uptake and accumulation of Cr, and the dissipation of B[a]P over 60 days. Results showed that single or joint contamination of Cr and B[a]P did not affect the plant growth relative to control treatments. However, the occurrence of B[a]P had an enhancing effect on the accumulation and translocation of Cr. The accumulation of Cr in shoot of plant significantly increased by ≥ 79 % in 50 mg kg(-1) Cr-B[a]P (1, 5, and 10 mg kg(-1)) treatments and by ≥ 86 % in 100 mg kg(-1) Cr-B[a]P (1, 5, and 10 mg kg(-1)) treatments relative to control treatments. The presence of plants did not enhance the dissipation of B[a]P in lower (1and 5 mg kg(-1)) B[a]P contaminated soils; however, over 60 days of planting Z. mays seemed to enhance the dissipation of B[a]P by over 60 % in 10 mg kg(-1) single contaminated soil and by 28 to 41 % in 10 mg kg(-1)B[a]P co-contaminated soil. This suggests that Z. mays might be a useful plant for the remediation of Cr-B[a]P co-contaminated soil.

  6. Toxicity of selected tremorgenic mycotoxins and related compounds to Spodoptera frugiperda and Heliothis zea.

    Science.gov (United States)

    Dowd, P F; Cole, R J; Vesonder, R F

    1988-12-01

    A series of tremorgenic mycotoxins and related compounds were tested for oral toxicity to the fall armyworm (Spodoptera frugiperda) and corn earworm (Heliothis zea) by incorporation of materials into artificial diets and examining mortality and weights after 7 days. Significant mortality to both insect species was caused with dihydroxyaflavinine and roseotoxin B, while significant mortality to H. zea was also caused by penitrem A at 25 ppm. After 7 days, weighs of larvae treated with 25 ppm penitrem A, roseotoxin B, and verruculogen were less than 50% of controls for both insect species. Weights of H. zea larvae treated with 25 ppb of penitrem A were less than 50% those of control larvae. Relative toxicities of the tremorgens and related compounds to insects compared to vertebrates are discussed.

  7. Spatial Diffusion of Influenza Outbreak-Related Climate Factors in Chiang Mai Province, Thailand

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    Marc Souris

    2012-10-01

    Full Text Available Influenza is one of the most important leading causes of respiratory illness in the countries located in the tropical areas of South East Asia and Thailand. In this study the climate factors associated with influenza incidence in Chiang Mai Province, Northern Thailand, were investigated. Identification of factors responsible for influenza outbreaks and the mapping of potential risk areas in Chiang Mai are long overdue. This work examines the association between yearly climate patterns between 2001 and 2008 and influenza outbreaks in the Chiang Mai Province. The climatic factors included the amount of rainfall, percent of rainy days, relative humidity, maximum, minimum temperatures and temperature difference. The study develops a statistical analysis to quantitatively assess the relationship between climate and influenza outbreaks and then evaluate its suitability for predicting influenza outbreaks. A multiple linear regression technique was used to fit the statistical model. The Inverse Distance Weighted (IDW interpolation and Geographic Information System (GIS techniques were used in mapping the spatial diffusion of influenza risk zones. The results show that there is a significance correlation between influenza outbreaks and climate factors for the majority of the studied area. A statistical analysis was conducted to assess the validity of the model comparing model outputs and actual outbreaks.

  8. Spatial diffusion of influenza outbreak-related climate factors in Chiang Mai Province, Thailand.

    Science.gov (United States)

    Nakapan, Supachai; Tripathi, Nitin Kumar; Tipdecho, Taravudh; Souris, Marc

    2012-10-24

    Influenza is one of the most important leading causes of respiratory illness in the countries located in the tropical areas of South East Asia and Thailand. In this study the climate factors associated with influenza incidence in Chiang Mai Province, Northern Thailand, were investigated. Identification of factors responsible for influenza outbreaks and the mapping of potential risk areas in Chiang Mai are long overdue. This work examines the association between yearly climate patterns between 2001 and 2008 and influenza outbreaks in the Chiang Mai Province. The climatic factors included the amount of rainfall, percent of rainy days, relative humidity, maximum, minimum temperatures and temperature difference. The study develops a statistical analysis to quantitatively assess the relationship between climate and influenza outbreaks and then evaluate its suitability for predicting influenza outbreaks. A multiple linear regression technique was used to fit the statistical model. The Inverse Distance Weighted (IDW) interpolation and Geographic Information System (GIS) techniques were used in mapping the spatial diffusion of influenza risk zones. The results show that there is a significance correlation between influenza outbreaks and climate factors for the majority of the studied area. A statistical analysis was conducted to assess the validity of the model comparing model outputs and actual outbreaks.

  9. Utilization of metarhizium anisopliae and vegetable extract for control of the spodoptera frugiperda and helicoverpa zea (lepidoptera: noctuidae in the corn

    Directory of Open Access Journals (Sweden)

    Eduardo Barbosa Beserra

    2008-05-01

    Full Text Available The potential use of the vegetable extracts and Metarhizium anisopliae about the population and damage of the Spodoptera frugiperda and Helicoverpa zea in corn, it was evaluated when planted in two spacings. The experiment was installed in the culture of corn, in the city of Lagoa Seca/PB, in two areas of 500 m2, in the spacings 0,8 x 0,4 and 0,4 x 0,4 m, with two and one plant for hole. The basis was constituited of: 1 Water as witness; 2 Metarhizium anisopliae; 3 Extracts of Mormodica charantia; 4 Metarhizium anisopliae + extracts of M. charantia; 5 M. anisopliae + manipueira. The results showed some statistical difference between the two spacings, with a larger number of collected caterpillars, 5,84, and a larger damage to the plant, 3,24, in the spacing 0,4 x 0,4 m, in relation to the spacing 0,8 x 0,4 m, within as average of 4,13 caterpillars and danificated of 2,71. There was not any significant interaction between the spacings and the products used for the control of S. frugiperda. However, there was a significant difference among the treatments, with a smaller number of caterpillars, 4,17, and a smaller medium damage to the plant, 2,81, when was used, M. anisopliae + extract of M. charantia. Considering to the control of the plaque the percentage of damage ears of corn by H. zea, weight and length of the ear of corn in corn, there wasn’t neither significant difference with regard to the spacing, neither with regard to the used treatments.

  10. Anti-inflammatory effects of Zea mays L. husk extracts.

    Science.gov (United States)

    Roh, Kyung-Baeg; Kim, Hyoyoung; Shin, Seungwoo; Kim, Young-Soo; Lee, Jung-A; Kim, Mi Ok; Jung, Eunsun; Lee, Jongsung; Park, Deokhoon

    2016-08-19

    Zea mays L. (Z. mays) has been used for human consumption in the various forms of meal, cooking oil, thickener in sauces and puddings, sweetener in processed food and beverage products, bio-disel. However, especially, in case of husk extract of Z. mays, little is known about its anti-inflammatory effects. Therefore, in this study, the anti-inflammatory effects of Z. mays husk extract (ZMHE) and its mechanisms of action were investigated. The husks of Z. Mays were harvested in kangwondo, Korea. To assess the anti-inflammatory activities of ZMHE, we examined effects of ZMHE on nitric oxide (NO) production, and release of soluble intercellular adhesion molecule-1 (sICAM-1) and eotaxin-1. The expression level of inducible nitric oxide synthase (iNOS) gene was also determined by Western blot and luciferase reporter assays. To determine its mechanisms of action, a luciferase reporter assay for nuclear factor kappa B (NF-kB) and activator protein-1 (AP-1) was introduced. ZMHE inhibited lipopolysaccharide (LPS)-induced production of NO in RAW264.7 cells. In addition, expression of iNOS gene was reduced, as confirmed by Western blot and luciferase reporter assays. Effects of ZMHE on the AP-1 and NF-kB promoters were examined to elucidate the mechanism of its anti-inflammatory activity. Activation of AP-1 and NF-kB promoters induced by LPS was significantly reduced by ZMHE treatment. In addition, LPS-induced production of sICAM-1 and IL-4-induced production of eotaxin-1 were all reduced by ZMHE. Our results indicate that ZMHE has anti-inflammatory effects by downregulating the expression of iNOS gene and its downregulation is mediated by inhibiting NF-kB and AP-1 signaling.

  11. Graviresponsiveness of surgically altered primary roots of Zea mays

    Science.gov (United States)

    Maimon, E.; Moore, R.

    1991-01-01

    We examined the gravitropic responses of surgically altered primary roots of Zea mays to determine the route by which gravitropic inhibitors move from the root tip to the elongating zone. Horizontally oriented roots, from which a 1-mm-wide girdle of epidermis plus 2-10 layers of cortex were removed from the apex of the elongating zone, curve downward. However, curvature occurred only apical to the girdle. Filling the girdle with mucilage-like material transmits curvature beyond the girdle. Vertically oriented roots with a half-girdle' (i.e. the epidermis and 2-10 layers of the cortex removed from half of the circumference of the apex of the elongating zone) curve away from the girdle. Inserting the half-girdle at the base of the elongating zone induces curvature towards the girdle. Filling the half-circumference girdles with mucilage-like material reduced curvature significantly. Stripping the epidermis and outer 2-5 layers of cortex from the terminal 1.5 cm of one side of a primary root induces curvature towards the cut, irrespective of the root's orientation to gravity. This effect is not due to desiccation since treated roots submerged in water also curved towards their cut surface. Coating a root's cut surface with a mucilage-like substance minimizes curvature. These results suggest that the outer cell-layers of the root, especially the epidermis, play an important role in root gravicurvature, and the gravitropic signals emanating from the root tip can move apoplastically through mucilage.

  12. Herbivory: Caterpillar saliva beats plant defences

    Science.gov (United States)

    Musser, Richard O.; Hum-Musser, Sue M.; Eichenseer, Herb; Peiffer, Michelle; Ervin, Gary; Murphy, J. Brad; Felton, Gary W.

    2002-04-01

    Blood-feeding arthropods secrete special salivary proteins that suppress the defensive reaction they induce in their hosts. This is in contrast to herbivores, which are thought to be helpless victims of plant defences elicited by their oral secretions. On the basis of the finding that caterpillar regurgitant can reduce the amount of toxic nicotine released by the tobacco plant Nicotiana tabacum, we investigate here whether specific salivary components from the caterpillar Helicoverpa zea might be responsible for this suppression. We find that the enzyme glucose oxidase counteracts the production of nicotine induced by the caterpillar feeding on the plant.

  13. Expression Patterns of Genes Involved in Ascorbate-Glutathione Cycle in Aphid-Infested Maize (Zea mays L.) Seedlings.

    Science.gov (United States)

    Sytykiewicz, Hubert

    2016-02-23

    Reduced forms of ascorbate (AsA) and glutathione (GSH) are among the most important non-enzymatic foliar antioxidants in maize (Zea mays L.). The survey was aimed to evaluate impact of bird cherry-oat aphid (Rhopalosiphum padi L.) or grain aphid (Sitobion avenae F.) herbivory on expression of genes related to ascorbate-glutathione (AsA-GSH) cycle in seedlings of six maize varieties (Ambrozja, Nana, Tasty Sweet, Touran, Waza, Złota Karłowa), differing in resistance to the cereal aphids. Relative expression of sixteen maize genes encoding isoenzymes of ascorbate peroxidase (APX1, APX2, APX3, APX4, APX5, APX6, APX7), monodehydroascorbate reductase (MDHAR1, MDHAR2, MDHAR3, MDHAR4), dehydroascorbate reductase (DHAR1, DHAR2, DHAR3) and glutathione reductase (GR1, GR2) was quantified. Furthermore, effect of hemipterans' attack on activity of APX, MDHAR, DHAR and GR enzymes, and the content of reduced and oxidized ascorbate and glutathione in maize plants were assessed. Seedling leaves of more resistant Z. mays varieties responded higher elevations in abundance of target transcripts. In addition, earlier and stronger aphid-triggered changes in activity of APX, MDHAR, DHAR and GR enzymes, and greater modulations in amount of the analyzed antioxidative metabolites were detected in foliar tissues of highly resistant Ambrozja genotype in relation to susceptible Tasty Sweet plants.

  14. A two-dimensional microscale model of gas exchange during photosynthesis in maize (Zea mays L.) leaves.

    Science.gov (United States)

    Retta, Moges; Ho, Quang Tri; Yin, Xinyou; Verboven, Pieter; Berghuijs, Herman N C; Struik, Paul C; Nicolaï, Bart M

    2016-05-01

    CO2 exchange in leaves of maize (Zea mays L.) was examined using a microscale model of combined gas diffusion and C4 photosynthesis kinetics at the leaf tissue level. Based on a generalized scheme of photosynthesis in NADP-malic enzyme type C4 plants, the model accounted for CO2 diffusion in a leaf tissue, CO2 hydration and assimilation in mesophyll cells, CO2 release from decarboxylation of C4 acids, CO2 fixation in bundle sheath cells and CO2 retro-diffusion from bundle sheath cells. The transport equations were solved over a realistic 2-D geometry of the Kranz anatomy obtained from light microscopy images. The predicted responses of photosynthesis rate to changes in ambient CO2 and irradiance compared well with those obtained from gas exchange measurements. A sensitivity analysis showed that the CO2 permeability of the mesophyll-bundle sheath and airspace-mesophyll interfaces strongly affected the rate of photosynthesis and bundle sheath conductance. Carbonic anhydrase influenced the rate of photosynthesis, especially at low intercellular CO2 levels. In addition, the suberin layer at the exposed surface of the bundle sheath cells was found beneficial in reducing the retro-diffusion. The model may serve as a tool to investigate CO2 diffusion further in relation to the Kranz anatomy in C4 plants.

  15. Improved tolerance of maize (Zea mays L.) to heavy metals by colonization of a dark septate endophyte (DSE) Exophiala pisciphila

    Energy Technology Data Exchange (ETDEWEB)

    Li, T.; Liu, M.J.; Zhang, X.T. [Key Laboratory of Conservation and Utilization for Bioresources, Yunnan University, Kunming, 650091 Yunnan (China); Zhang, H.B. [Key Laboratory of Conservation and Utilization for Bioresources, Yunnan University, Kunming, 650091 Yunnan (China); Department of Biology, Yunnan University, Kunming, 650091 Yunnan (China); Sha, T. [Key Laboratory of Conservation and Utilization for Bioresources, Yunnan University, Kunming, 650091 Yunnan (China); Zhao, Z.W., E-mail: zhaozhw@ynu.edu.cn [Key Laboratory of Conservation and Utilization for Bioresources, Yunnan University, Kunming, 650091 Yunnan (China)

    2011-02-15

    Dark septate endophytes (DSE) are ubiquitous and abundant in stressful environments including heavy metal (HM) stress. However, our knowledge about the roles of DSE in improving HM tolerance of their host plants is poor. In this study, maize (Zea mays L.) was inoculated with a HM tolerant DSE strain Exophiala pisciphila H93 in lead (Pb), zinc (Zn), and cadmium (Cd) contaminated soils. E. pisciphila H93 successfully colonized and formed typical DSE structures in the inoculated maize roots. Colonization of E. pisciphila H93 alleviated the deleterious effects of excessive HM supplements and promoted the growth of maize (roots and shoots) under HM stress conditions, though it significantly decreased the biomass of inoculated maize under no HM stress. Further analysis showed that the colonization of E. pisciphila H93 improved the tolerance of maize to HM by restricting the translocation of HM ions from roots to shoots. This study demonstrated that under higher HM stress, such a mutual symbiosis between E. pisciphila and its host (maize) may be an efficient strategy to survive in the stressful environments. - Research Highlights: {yields}Effect of DSE (E. pisciphila) on heavy metal tolerance of maize host was studied. {yields}DSE alleviated the deleterious effect of excessive heavy metals on maize. {yields}DSE restricted the transfer of heavy metals from the roots to shoots in maize. {yields}DSE colonization improved the tolerance of their host plants to heavy metals.

  16. Study of effects of Bt maize (Zea mays) events on Lepidoptera Ostrinia nubilalis, Sesamia nonagrioidesin southwestern France.

    Science.gov (United States)

    Folcher, L; Eychenne, N; Weissenberger, A; Jarry, M; Regnault-Roger, C; Delos, M

    2006-01-01

    Crops of maize (Zea mays L.) were conducted in southwestern France with GMO (Genetic Modified Organism) vs isogenetic varieties in order to verify the control of European Corn Borer (ECB) Ostrinia nubilalis (Hübner) and the Corn Stalk Borer (CBS) Sesamia nonagrioides (Lefevbre) by GMO in field conditions. The bioassays were carried out in 1998 and 1999 before moratorium, then in 2005. Experiments involved respectively 18, 12 and 19 fields cultivated with Furio/Furio cb (GMO), Cecilia/ Elgina (GMO) and PR33P66/PR33P67 (GMO) varieties. These transgenic events expressed Cry1A(b) protein (Bt maize). Plants were noted for insect infestation assessment (number of larvae in stalks and ears per plant). Statistical tests used t-test on couple of plots. Results showed a significant difference in the density of both ECB and CBS between control and the two transgenic events. The two transgenic events acted differently. The control of the two Bt events on the two pests were differentiated and discussed. These experiments underlined the importance of field evaluation for testing real effects of transgenic events on crop according the environmental context.

  17. Studies on the growth and indole-3-acetic acid and abscisic acid content of Zea mays seedlings grown in microgravity

    Science.gov (United States)

    Schulze, A.; Jensen, P. J.; Desrosiers, M.; Buta, J. G.; Bandurski, R. S.

    1992-01-01

    Measurements were made of the fresh weight, dry weight, dry weight-fresh weight ratio, free and conjugated indole-3-acetic acid, and free and conjugated abscisic acid in seedlings of Zea mays grown in darkness in microgravity and on earth. Imbibition of the dry kernels was 17 h prior to launch. Growth was for 5 d at ambient orbiter temperature and at a chronic accelerational force of the order of 3 x 10(-5) times earth gravity. Weights and hormone content of the microgravity seedlings were, with minor exceptions, not statistically different from seedlings grown in normal gravity. The tissues of the shuttle-grown plants appeared normal and the seedlings differed only in the lack of orientation of roots and shoots. These findings, based upon 5 d of growth in microgravity, cannot be extrapolated to growth in microgravity for weeks, months, and years, as might occur on a space station. Nonetheless, it is encouraging, for prospects of bioregeneration of the atmosphere and food production in a space station, that no pronounced differences in the parameters measured were apparent during the 5 d of plant seedling growth in microgravity.

  18. Genetic characterization and linkage disequilibrium mapping of resistance to gray leaf spot in maize(Zea mays L.)

    Institute of Scientific and Technical Information of China (English)

    Liyu; Shi; Xiangling; Lv; Jianfeng; Weng; Hanyong; Zhu; Changlin; Liu; Zhuanfang; Hao; Yu; Zhou; Degui; Zhang; Mingshun; Li; Xiaoke; Ci; Xinhai; Li; Shihuang; Zhang

    2014-01-01

    Gray leaf spot(GLS),caused by Cercospora zeae-maydis,is an important foliar disease of maize(Zea mays L.)worldwide,resistance to which is controlled by multiple quantitative trait loci(QTL).To gain insights into the genetic architecture underlying the resistance to this disease,an association mapping population consisting of 161 inbred lines was evaluated for resistance to GLS in a plant pathology nursery at Shenyang in 2010 and 2011.Subsequently,a genome-wide association study,using 41,101 single-nucleotide polymorphisms(SNPs),identified 51 SNPs significantly(P<0.001)associated with GLS resistance,which could be converted into 31 QTL.In addition,three candidate genes related to plant defense were identified,including nucleotidebinding-site/leucine-rich repeat,receptor-like kinase genes similar to those involved in basal defense.Two genic SNPs,PZE-103142893 and PZE-109119001,associated with GLS resistance in chromosome bins 3.07 and 9.07,can be used for marker-assisted selection(MAS)of GLS resistance.These results provide an important resource for developing molecular markers closely linked with the target trait,enhancing breeding efficiency.

  19. Determination of Genetic Coefficients of Some Maize (Zea mays L. Cultivars of Iran for Application in Crop Simulation Models

    Directory of Open Access Journals (Sweden)

    S Rahimi Moghaddam

    2015-09-01

    Full Text Available A field experiment was conducted at the research field of the University of Lorestan in 2011 as a randomized complete block design with three replications to estimate genetic coefficients of some maize (Zea mays L. cultivars. Treatments include six maize cultivars (T.V.C.767 and S.C.704 from late maturing group, T N.S640 and Maxima from mid-maturing group, and Koppany and D.C.370 from early maturing group. Results showed that there were significant differences among cultivars in terms of stem dry weight, maximum number of kernel per ear, thermal time from the flag leaf appearance to flowering, thermal time from flowering to maturity, phyllochron interval, grain weight, maximum plant height and minimum growth degree days during vegetative period. The highest (649.2 and lowest (350.6 maximum number of kernel per ear belonged to cultivars S.C.704 and D.C.370, respectively. Also, the highest and lowest stem dry weight, phyllochron interval and maximum plant height belonged to cultivars S.C.704 and D.C.370, respectively. Among genetic coefficients, the minimum growth degree days required for vegetative growth and the maximum number of kernel per ear had the greatest correlation with grain yield (r=0.72 and r=0.84, respectively. Overall, the results portrayed that the estimated genetic coefficients of the cultivars are not identical in different models and varied in a defined range.

  20. INFLUENCE OF FUNGI OF THE GENUS TRICHODERMA ON PHYTOAVAILABILITY CADMIUM AND PHYSIOLOGICAL CONDITION OF MAIZE (ZEA MAYS

    Directory of Open Access Journals (Sweden)

    Magdalena Marchel

    2015-02-01

    Full Text Available The aim of conducted research was to determine in what degree inoculation of soil by fungi Trichoderma modifies process of phytoavailability of cadmium through roots and above ground parts of maize (Zea mays and how it affects cadmium activity as damaging factor of photosynthetic apparatus of plants. Outline of vase experiment covered 5 objects (control without addition of cadmium and 4 objects with increasing amount of cadmium in amount from 10 to 80 mg.kg-1 d.m. soil, and within each object two variants: soil without (-T and with (+T addition of fungi of Trichoderma (+T in shape of granulated preparation of Trianum–G in amount of 750 g.m-3 soil. Increasing amount of cadmium in surface caused decrease of harvest size of roots and above ground parts of maize, but inoculation of surface by Trichoderma fungi softened those changes. Amount of cadmium in plants was increasing promotionally to increasing amount of that metal in soil, but the presence of fungi of Trichoderma type caused decrease of phytoavailability cadmium by above ground parts of maize. Decrease parameters of chlorophyll fluorescence F0, FM, Fv, Fv/FM Fv/F0 showed lack of disturbances in photosynthetic apparatus of maize despite decrease the amount of chlorophyll in leaves under the influence of inserted cadmium doses to soil.

  1. Occurrence and metabolism of 7-hydroxy-2-indolinone-3-acetic acid in Zea mays

    Science.gov (United States)

    Lewer, P.; Bandurski, R. S.

    1987-01-01

    7-Hydroxy-2-indolinone-3-acetic acid was identified as a catabolite of indole-3-acetic acid in germinating kernels of Zea mays and found to be present in amounts of ca 3.1 nmol/kernel. 7-Hydroxy-2-indolinone-3-acetic acid was shown to be a biosynthetic intermediate between 2-indolinone-3-acetic acid and 7-hydroxy-2-indolinone-3-acetic acid-7'-O-glucoside in both kernels and roots of Zea mays. Further metabolism of 7-hydroxy-2-[5-3H]-indolinone-3-acetic acid-7'-O-glucoside occurred to yield tritiated water plus, as yet, uncharacterized products.

  2. Bacterial communities in the rhizosphere of amilaceous maize (Zea mays L. as assessed by pyrosequencing

    Directory of Open Access Journals (Sweden)

    David Correa-Galeote

    2016-07-01

    Full Text Available Maize (Zea mays L. is the staple diet of the native peasants in the Quechua region of the Peruvian Andes who continue growing it in small plots called chacras following ancestral traditions. The abundance and structure of bacterial communities associated with the roots of amilaceous maize has not been studied in Andean chacras. Accordingly, the main objective of this study was to describe the rhizospheric bacterial diversity of amilaceous maize grown either in the presence or the absence of bur clover cultivated in soils from the Quechua maize belt. Three 16S rRNA gene libraries, one corresponding to sequences of bacteria from bulk soil of a chacra maintained under fallow conditions, the second from the rhizosphere of maize-cultivated soils, and the third prepared from rhizospheric soil of maize cultivated in intercropping with bur clover were examined using pyrosequencing tags spanning the V4 and V5 hypervariable regions of the gene. A total of 26031 sequences were found that grouped into 5955 distinct operational taxonomic units which distributed in 309 genera. The numbers of OTUs in the libraries from the maize-cultivated soils were significantly higher than those found in the libraries from bulk soil. One hundred ninety seven genera were found in the bulk soil library and 234 and 203 were in those from the maize and maize/bur clover-cultivated soils. Sixteen out of the 309 genera had a relative abundance higher than 0.5% and the were (in decreasing order of abundance Gp4, Gp6, Flavobacterium, Subdivision3 genera incertae sedis of the Verrucomicrobia phylum, Gemmatimonas, Dechloromonas, Ohtaekwangia, Rhodoferax, Gaiella, Opitutus, Gp7, Spartobacteria genera incertae sedis, Terrimonas, Gp5, Steroidobacter and Parcubacteria genera incertae sedis. Genera Gp4 and Gp6 of the Acidobacteria, Gemmatimonas and Rhodoferax were the most abundant in bulk soil, whereas Flavobacterium, Dechloromonas and Ohtaekwangia were the main genera in the rhizosphere

  3. Lipid extracted microalgal biomass residue as a fertilizer substitute for Zea mays L

    Directory of Open Access Journals (Sweden)

    Rahulkumar eMaurya

    2016-01-01

    Full Text Available High volumes of lipid extracted microalgal biomass residues (LMBRs are expected to be produced upon commencement of biodiesel production on a large scale, thus necessitating its value addition for sustainable development. LMBRs of Chlorella variabilis and Lyngbya majuscula were employed to substitute the nitrogen content of recommended rate of fertilizer (RRF for Zea mays L. The pot experiment comprised of 10 treatments, i.e. T1 (No fertilizer; T2 (RRF-120 N: 60 P2O5: 40 K2O kg ha-1; T3 to T6 -100, 75, 50 and 25% N through LMBR of the Chlorella sp., respectively; T7 to T10 -100, 75, 50 and 25% N through LMBR of Lyngbya sp., respectively. It was found that all LMBR substitution treatments were at par to RRF with respect to grain yield production. T10 gave the highest grain yield (65.16 g plant-1, which was closely followed by that (63.48 g plant-1 under T5. T10 also recorded the highest phosphorus and potassium contents in grains. T4 was markedly superior over control in terms of dry matter accumulation (DMA as well as carbohydrate content, which was ascribed to higher pigment content and photosynthetic activity in leaves. Even though considerably lower DMA was obtained in Lyngbya treatments, which might have been due to the presence of some toxic factors, no reduction in grain yield was apparent. The length of the tassel was significantly higher in either of the LMBRs at any substitution rates over RRF, except T6 and T7. The ascorbate peroxidase activity decreased with decreasing dose of Chlorella LMBR, while all the Lyngbya LMBR treatments recorded lower activity, which were at par with each other. Among the Chlorella treatments, only T5 recorded significantly higher values of glutathione reductase activity over RRF, while the rest were at par. There were significant increases in carbohydrate and crude fat, respectively, only in T4 and T3 over RRF, while no change was observed in crude protein due to LMBR treatments. Apparently, there was no

  4. CRP1 Protein: (dis)similarities between Arabidopsis thaliana and Zea mays

    Science.gov (United States)

    Ferrari, Roberto; Tadini, Luca; Moratti, Fabio; Lehniger, Marie-Kristin; Costa, Alex; Rossi, Fabio; Colombo, Monica; Masiero, Simona; Schmitz-Linneweber, Christian; Pesaresi, Paolo

    2017-01-01

    Biogenesis of chloroplasts in higher plants is initiated from proplastids, and involves a series of processes by which a plastid able to perform photosynthesis, to synthesize amino acids, lipids, and phytohormones is formed. All plastid protein complexes are composed of subunits encoded by the nucleus and chloroplast genomes, which require a coordinated gene expression to produce the correct concentrations of organellar proteins and to maintain organelle function. To achieve this, hundreds of nucleus-encoded factors are imported into the chloroplast to control plastid gene expression. Among these factors, members of the Pentatricopeptide Repeat (PPR) containing protein family have emerged as key regulators of the organellar post–transcriptional processing. PPR proteins represent a large family in plants, and the extent to which PPR functions are conserved between dicots and monocots deserves evaluation, in light of differences in photosynthetic metabolism (C3 vs. C4) and localization of chloroplast biogenesis (mesophyll vs. bundle sheath cells). In this work we investigated the role played in the process of chloroplast biogenesis by At5g42310, a member of the Arabidopsis PPR family which we here refer to as AtCRP1 (Chloroplast RNA Processing 1), providing a comparison with the orthologous ZmCRP1 protein from Zea mays. Loss-of-function atcrp1 mutants are characterized by yellow-albinotic cotyledons and leaves owing to defects in the accumulation of subunits of the thylakoid protein complexes. As in the case of ZmCRP1, AtCRP1 associates with the 5′ UTRs of both psaC and, albeit very weakly, petA transcripts, indicating that the role of CRP1 as regulator of chloroplast protein synthesis has been conserved between maize and Arabidopsis. AtCRP1 also interacts with the petB-petD intergenic region and is required for the generation of petB and petD monocistronic RNAs. A similar role has been also attributed to ZmCRP1, although the direct interaction of ZmCRP1 with the

  5. Identification and suppression of the p-coumaroyl CoA:hydroxycinnamyl alcohol transferase in Zea mays L.

    Science.gov (United States)

    Marita, Jane M; Hatfield, Ronald D; Rancour, David M; Frost, Kenneth E

    2014-06-01

    Grasses, such as Zea mays L. (maize), contain relatively high levels of p-coumarates (pCA) within their cell walls. Incorporation of pCA into cell walls is believed to be due to a hydroxycinnamyl transferase that couples pCA to monolignols. To understand the role of pCA in maize development, the p-coumaroyl CoA:hydroxycinnamyl alcohol transferase (pCAT) was isolated and purified from maize stems. Purified pCAT was subjected to partial trypsin digestion, and peptides were sequenced by tandem mass spectrometry. TBLASTN analysis of the acquired peptide sequences identified a single full-length maize cDNA clone encoding all the peptide sequences obtained from the purified enzyme. The cDNA clone was obtained and used to generate an RNAi construct for suppressing pCAT expression in maize. Here we describe the effects of suppression of pCAT in maize. Primary screening of transgenic maize seedling leaves using a new rapid analytical platform was used to identify plants with decreased amounts of pCA. Using this screening method, mature leaves from fully developed plants were analyzed, confirming reduced pCA levels throughout plant development. Complete analysis of isolated cell walls from mature transgenic stems and leaves revealed that lignin levels did not change, but pCA levels decreased and the lignin composition was altered. Transgenic plants with the lowest levels of pCA had decreased levels of syringyl units in the lignin. Thus, altering the levels of pCAT expression in maize leads to altered lignin composition, but does not appear to alter the total amount of lignin present in the cell walls.

  6. Distinct roles of electric and hydraulic signals on the reaction of leaf gas exchange upon re-irrigation in Zea mays L.

    Science.gov (United States)

    Grams, Thorsten E E; Koziolek, Christiane; Lautner, Silke; Matyssek, Rainer; Fromm, Jörg

    2007-01-01

    The hypothesis that electric and hydraulic long-distance signals modify photosynthesis and stomatal aperture upon re-irrigation in intact drought-stressed plants was examined. Maize plants (Zea mays L.) were exposed to drought conditions by decreasing the soil water content to 40-50% of field capacity. The decrease in water content resulted in a decline in stomatal conductance to 50-60% of the level in well-watered plants. Re-irrigation of the plants initiated both hydraulic and electric signals, followed by a two-phase response of the net CO2 uptake rate and stomatal conductance of leaves. The transitional first phase (phase 1) is characterized by a rapid decrease in both levels. In the second phase (phase 2), both parameters gradually increase to levels above those of drought-stressed plants. Elimination of either the hydraulic signal by compensatory pressure application to the root system, or of the electric signal by cooling of the leaf blade gave evidence that the two signals (1) propagated independently from each other and (2) triggered the two-phase response in leaf gas exchange. The results provided evidence that the hydraulic signal initiated a hydropassive decrease in stomatal aperture and for the involvement of electric signals in the regulation of photosynthesis of drought-stressed plants.

  7. Uptake of zinc, cadmium and phosphorus by arbuscular mycorrhizal maize (Zea mays L.) from a low available phosphorus calcareous soil spiked with zinc and cadmium.

    Science.gov (United States)

    Shen, Hong; Christie, Peter; Li, Xiaolin

    2006-01-01

    In a multifactorial pot experiment, maize (Zea mays L.) with or without inoculation with the arbuscular mycorrhizal (AM) fungus Glomus mosseae BEG167 was grown in a sterilized soil spiked with three levels of zinc (0, 300 and 900 mg Zn kg(-1) soil) and three levels of cadmium (0, 25 and 100 mg Cd kg(-1) soil). At harvest after 8 weeks of growth, the proportion of root length of inoculated plants colonized decreased with increasing Zn or Cd addition, and was 56% in the absence of both metals and was reduced significantly to 27% in the presence of the higher levels of both metals. Mycorrhizal plants had higher biomass than non-mycorrhizal controls except at the highest soil level of Cd. Cadmium had more pronounced effects on plant biomass than did Zn at the levels studied and the two metals showed a significant interaction. The data suggest that mycorrhizal inoculation increased plant growth with enhancement of P nutrition, perhaps increasing plant tolerance to Zn and Cd by a dilution effect. AM inoculation also led to higher soil solution pH after harvest, possibly reducing the availability of the metals for plant uptake, and lowered the concentrations of soluble Zn and Cd in the soil solution, perhaps by adsorption onto the extrametrical mycelium.

  8. Exploring spatial patterns and hotspots of diarrhea in Chiang Mai, Thailand

    Directory of Open Access Journals (Sweden)

    Tripathi Nitin K

    2009-06-01

    Full Text Available Abstract Background Diarrhea is a major public health problem in Thailand. The Ministry of Public Health, Thailand, has been trying to monitor and control this disease for many years. The methodology and the results from this study could be useful for public health officers to develop a system to monitor and prevent diarrhea outbreaks. Methods The objective of this study was to analyse the epidemic outbreak patterns of diarrhea in Chiang Mai province, Northern Thailand, in terms of their geographical distributions and hotspot identification. The data of patients with diarrhea at village level and the 2001–2006 population censuses were collected to achieve the objective. Spatial analysis, using geographic information systems (GIS and other methods, was used to uncover the hidden phenomena from the data. In the data analysis section, spatial statistics such as quadrant analysis (QA, nearest neighbour analysis (NNA, and spatial autocorrelation analysis (SAA, were used to identify the spatial patterns of diarrhea in Chiang Mai province. In addition, local indicators of spatial association (LISA and kernel density (KD estimation were used to detect diarrhea hotspots using data at village level. Results The hotspot maps produced by the LISA and KD techniques showed spatial trend patterns of diarrhea diffusion. Villages in the middle and northern regions revealed higher incidences. Also, the spatial patterns of diarrhea during the years 2001 and 2006 were found to represent spatially clustered patterns, both at global and local scales. Conclusion Spatial analysis methods in GIS revealed the spatial patterns and hotspots of diarrhea in Chiang Mai province from the year 2001 to 2006. To implement specific and geographically appropriate public health risk-reduction programs, the use of such spatial analysis tools may become an integral component in the epidemiologic description, analysis, and risk assessment of diarrhea.

  9. A importância do design para tornar as redes sociais mais interativas

    Directory of Open Access Journals (Sweden)

    Bruno Cesar Soares Santos

    2013-06-01

    Full Text Available A concepção do design é uma das etapas mais importantes da construção de websites, por ordenar as informações e os componentes visuais das páginas de forma a articular um sistema de eficiente e fácil utilização. No caso das Redes Sociais On-line, que são sites com a proposta de promover a interação social e favorecer a comunicação entre usuários em vários contextos (pessoais, profissionais ou mais específicos, o design deve ser concebido levando-se em conta alguns conceitos e necessidades peculiares. Garantir usabilidade na relação pessoa x máquina e interação entre os seus usuários são necessidades que só serão supridas por meio de uma interface construída pensando-se na experiência de quem utilizará a rede, tarefa que cabe ao designer. Este artigo investiga a importância do design de interação com foco em usabilidade, no cumprimento da tarefa descrita anteriormente, e apresenta ocase do uso do design no Facebook, a rede social mais acessada do mundo. Como complemento, o estudo pontua algumas inconsistências e necessidades latentes no design dos sites de redes sociais e lista os pontos positivos e potencialidades que eles apresentam.

  10. ADOLESCENTES COM SONOLÊNCIA DIURNA EXCESSIVA PASSAM MAIS TEMPO EM COMPORTAMENTO SEDENTÁRIO

    Directory of Open Access Journals (Sweden)

    Érico Pereira Gomes Felden

    Full Text Available RESUMO Introdução: A diminuição da atividade física, a baixa duração do sono e o aumento do tempo sentado têm sido cada vez mais percebidos na adolescência. Objetivos: Investigar a associação entre comportamento sedentário e variáveis de sono (sonolência diurna e duração de sono de adolescentes de um município de pequeno porte do sul do Brasil. Métodos: Trata-se de uma amostra representativa, de base escolar, do município de Maravilha, SC, Brasil, formada por 516 adolescentes de ambos os sexos, com 10 a 19 anos de idade. Foram investigadas as associações entre comportamentos sedentários, sono, percepção de estresse e atividade física. O comportamento sedentário foi investigado por meio do tempo sentado durante o dia. Além disso, outras questões foram investigadas, como: sexo, faixa etária, turno escolar, local de domicílio, renda e grau de instrução do chefe de família, duração do sono e sonolência diurna, percepção de estresse e nível de atividade física. Resultados: A prevalência de baixa duração do sono foi de 53,6%. A média de tempo sentado durante um dia de semana foi de 382,2 min., sendo superior no sexo feminino (p = 0,001. Os adolescentes com baixa duração do sono apresentaram valores médios mais altos de tempo sentado (p < 0,001, sonolência diurna (p < 0,001 e sonolência em sala de aula (p < 0,001. Os adolescentes com maior sonolência tinham 4,97 (IC: 2,50-9,87 vezes mais chance de ter comportamento sedentário elevado. Conclusão: Adolescentes com maior sonolência diurna apresentaram maior tempo dedicado aos comportamentos sedentários. Assim, as medidas de educação para um estilo de vida mais ativo na adolescência devem observar também questões gerais sobre sono e sonolência diurna.

  11. Palmeiras lucra com arena mais do que 3 rivais juntos, mostra estudo

    OpenAIRE

    Itri, Bernardo

    2015-01-01

    No primeiro ano em que começou o Brasileiro com sua nova arena, o Palmeiras lucrou com bilheteria mais do que o Corinthians, São Paulo e Santos juntos, aponta levantamento da Diretoria de Análise de Políticas Públicas da FGV. O estudo diz que o clube alviverde faturou R$ 8,4 milhões nas dez primeiras rodadas do torneio nacional, e os três rivais do Estado, R$ 5,4 milhões.

  12. The Need To Reposition The Insurance Logistics Management In M.A.I. Units

    Directory of Open Access Journals (Sweden)

    Paul Gheorghe

    2017-03-01

    Full Text Available Logistics, considered by some authors as "a science of the future, has the aim ofof study dimensioning and correlation optimal flow of information and goods, in order to continuously adapt the organization to the environment" and is an essential component of management entity, especially in the context propagation production concept JIT (just in time, extended to financial security. Providing specialized management and structural compatibility between M.A.I. units components and greater specialization of staff with similar tasks are achievable when the uniformity of the organization structure of the existing logistics structures subordinated M. A.I.

  13. PRODUÇÃO DE COSMÉTICOS DE FORMA MAIS SUSTENTÁVEL

    OpenAIRE

    Gonçalves, Jennifer Sumar; Henkes, Jairo Afonso

    2016-01-01

    A nossa qualidade de vida depende da nossa capacidade de viver dentro dos limites e recursos naturais disponíveis e a sociedade está se conscientizando cada vez disso. É crescente a busca de empresas do setor de cosméticos em se tornar cada vez mais sustentável, combinar o retorno econômico com suas obrigações sociais e ambientais e o objetivo desse trabalho é conscientizar que uma empresa de pequeno porte também pode alcançar esse objetivo. Veremos como funciona uma pequena empresa de cosmét...

  14. GEORAIL 2011 : Symposium international Géotechnique ferroviaire, Paris, 19-20 mai 2011, Volume 1

    OpenAIRE

    2011-01-01

    Le symposium international sur la Géotechnique ferroviaire s'est tenu les 19 et 20 mai 2011 à Paris (France). Les actes de ce symposium comportent deux volumes. Ce premier volume regroupe les communications présentées au symposium. Elles traitent de sujets variés concernant tous les aspects de la géotechnique ferroviaire, regroupés en cinq thèmes : - la conception et le calcul, - les procédés, matériaux et ouvrages expérimentaux, - les retours d'expérience, - des exemples de chantiers, - la v...

  15. Production and characterization of amylases from Zea mays malt

    Directory of Open Access Journals (Sweden)

    Joana Paula Menezes Biazus

    2009-08-01

    Full Text Available In this work the α and β-amylase enzymes were obtained from maize (Zea mays malt and were biochemistry characterized. A germination study to obtain the maize malt with good amylase activity was made. The maize seeds were germinated in laboratory and the enzymatic activity was measured daily. Activity dependence to germination time were fitted to an exponential model (A=A0eµt, which showed that the behaviour of enzymatic activity in the germination process was similar to the growth of the microorganism. Its model could be applied to describe the mechanism of α-amylase production for each maize varieties and others cereals. Maize malt characterization showed that α and β-amylase had optimal pH between 4-6.5, optimal temperature 50 and 90ºC, and molecular weight of 67.4 and 47.5kDa, respectively. This work contributed with the advances in biotechnology generating of conditions for application of a new and of low price amylases source.Neste trabalho as enzimas α e β-amilases foram obtidas de malte de milho e depois foram caracterizadas bioquimicamente. Um estudo da germinação foi feito para obtenção do malte com boa atividade amilásica. A germinação ocorreu em escala laboratorial e a atividade enzimática foi medida diariamente. Um modelo exponencial do tipo A=A0eµt foi ajustado a dependência do tempo de germinação com a atividade, mostrando que o comportamento da atividade enzimática no processo de germinação é semelhante ao crescimento de microorganismos. Este modelo pode ser aplicado para descrever o mecanismo de produção da α-amilase para cada variedade de milho e de outros cereais. A caracterização do malte de milho mostrou que as α e β-amilase têm pH ótimo entre 4,0-6,5, temperatura ótima de 50 e 90ºC, e massa molar de 67,4 e 47,5 kDa, respectivamente. Este trabalho contribuiu com os avanços da biotecnologia gerando condições de emprego de uma nova e barata fonte de amilases.

  16. Field inoculation of arbuscular mycorrhiza on maize (Zea mays L. under low inputs: preliminary study on quantitative and qualitative aspects

    Directory of Open Access Journals (Sweden)

    Emilio Sabia

    2015-03-01

    Full Text Available Arbuscular mycorrhizal symbiosis contributes to the sustainability of soil-plant system. A field experiment was conducted to examine the effect of arbuscular mycorrhiza (AM on quantitative and qualitative performance in forage maize (Zea mays L.. Within the project Sviluppo di modelli zootecnici ai fini della sostenibilità (SOS-ZOOT a trial was conducted at the experimental farm of the Agricultural Research Council in Bella (PZ, located in Basilicata region (Southern Italy at 360 m asl, characterised by an annual rainfall of approximately 650 mm. For spring sowing, two plots of 2500 m2 were used, one sown with seeds inoculated with AM (M, 1.0 kg/ha, and the other one with non-inoculated seeds (NM. After 120 days after sowing, when plants showed 30% dry matter, five replicates of 1 m2 per plot were used to estimate dry matter yield (DMY, while half plot was dedicated to the assessment of grain production. For each replicate, three representative plants were considered; each plant was measured for height and was divided into leaves, stem and ear. For each plot, the following constituents were determined: crude protein, ash, ether extract, crude fibre (CF, fractions of fibre [neutral detergent (NDF, acid detergent fibre (ADF and sulphuric acid lignin] and phosphorus (P. Throughout the period of plants’ growth, no herbicides, organic or inorganic fertilisation, and irrigation water were distributed. The preliminary results revealed a significant effect of AM inoculation on forage maize DMY, P content in the whole plant, into the leaves and on the quality of steam. The M thesis showed a significant increase in terms of DMY in comparison with the NM thesis: 21.2 vs 17.9 t/ha (P<0.05. The mycorrhized whole plants [0.22 vs 0.17% dry matter (DM, P<0.05] and leaves (0.14 vs 0.09% DM, P<0.05 showed an increased P content. The stems of M plants showed a content of CF, NDF, ADF and Ash significantly lower compared with NM plants. No significant

  17. Isolation of EF1gamma from calli regenerating SSH library in Maize (Zea mays).

    Science.gov (United States)

    Xia, Y L; Ding, J; Zhang, Z M; Rong, T Z; Shi, L Y; Pan, G T

    2007-12-01

    18599Hong, a good Maize (Zea mays) inbred line as well as good transformation acceptor with high regeneration capacity, was used for isolating embryonic callus regeneration genes. Subtractive library was constructed by Suppression subtractive hybridization and screened by Reverse Northern Hybridization. The clones of No. 27 was randomly picked to sequence. NCBI blastx results showed the similarity to elongation factor 1gamma in rice.

  18. Potassium fertilization mitigates the adverse effects of drought on selected Zea mays cultivars

    Science.gov (United States)

    In the present study, the role of potassium (K) in mitigating the adverse effects of drought stress (DS) on 2 maize (Zea mays L.) cultivars, ‘Shaandan 9’ (S9; drought-tolerant) and ‘Shaandan 911’ (S911; drought-sensitive), was assessed. K application increased dry matter (DM) across all growth stage...

  19. Identification and characterization of a Zea mays line carrying a transposon-tagged ENOD40

    NARCIS (Netherlands)

    Compaan, B.; Ruttink, T.; Albrecht, C.; Meeley, R.; Bisseling, T.; Franssen, H.G.J.M.

    2003-01-01

    In Zea mays, two ENOD40 homologous were identified that show only 30% of sequence homology to each other. We identified line e40-mum1 carrying a Mu transposon inserted in ZmENOD40-1, the maize gene that has the highest homology to leguminous ENOD40. The insertion causes a dramatic reduction of the Z

  20. Chromosomal Location by Use of Trisomics and New Alleles of an Endopeptidase in Zea Mays

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Gissel; Scandalios, John G.

    1974-01-01

    An association was found earlier between the Ep1 gene locus coding for an endopeptidase and the endosperm color gene Y1 on chromosome 6 of Zea mays. By employing primary trisomics we have unequivocally placed the Ep1 gene on chromosome 6, closely linked to the Y1 locus. Additionally we describe new...

  1. Cloning and sequencing of the casein kinase 2 alpha subunit from Zea mays

    DEFF Research Database (Denmark)

    Dobrowolska, G; Boldyreff, B; Issinger, O G

    1991-01-01

    The nucleotide sequence of the cDNA coding for the alpha subunit of casein kinase 2 of Zea mays has been determined. The cDNA clone contains an open reading frame of 996 nucleotides encoding a polypeptide comprising 332 amino acids. The primary amino acid sequence exhibits 75% identity to the alpha...

  2. Purification and characterization of recombinant protein kinase CK2 from Zea mays expressed in Escherichia coli

    DEFF Research Database (Denmark)

    Riera, Marta; Pages, Montserrat; Issinger, Olaf Georg

    2003-01-01

    Recombinant protein kinase subunits rmCK2alpha-1 and rmCK2beta-1 from Zea mays were expressed separately in Escherichia coli and assembled to a fully active tetrameric holoenzyme complex in vitro. The obtained maize holoenzyme was purified to homogeneity, biochemically characterized, and compared...

  3. Characterization of phenylpropanoid pathway genes within European maize (Zea mays L.) inbreds

    DEFF Research Database (Denmark)

    Andersen, Jeppe Reitan; Zein, Imad; Wenzel, Gerhard

    2008-01-01

    genomic fragments of six putative phenylpropanoid pathway genes in a panel of elite European inbred lines of maize (Zea mays L.) contrasting in forage quality traits. Six loci, encoding C4H, 4CL1, 4CL2, C3H, F5H, and CAD, displayed different levels of nucleotide diversity and linkage disequilibrium (LD...

  4. Defining the role of the MADS-box gene, Zea agamous like1, in maize domestication

    Science.gov (United States)

    Genomic scans for genes that show the signature of past selection have been widely applied to a number of species and have identified a large number of selection candidate genes. In cultivated maize (Zea mays ssp. mays) selection scans have identified several hundred candidate domestication genes...

  5. Characterization of phenylpropanoid pathway genes within European maize (Zea mays L.) inbreds

    DEFF Research Database (Denmark)

    Andersen, Jeppe Reitan; Zein, Imad; Wenzel, Gerhard;

    2008-01-01

    genomic fragments of six putative phenylpropanoid pathway genes in a panel of elite European inbred lines of maize (Zea mays L.) contrasting in forage quality traits. Six loci, encoding C4H, 4CL1, 4CL2, C3H, F5H, and CAD, displayed different levels of nucleotide diversity and linkage disequilibrium (LD...

  6. Identification and characterization of a Zea mays line carrying a transposon-tagged ENOD40

    NARCIS (Netherlands)

    Compaan, B.; Ruttink, T.; Albrecht, C.; Meeley, R.; Bisseling, T.; Franssen, H.G.J.M.

    2003-01-01

    In Zea mays, two ENOD40 homologous were identified that show only 30% of sequence homology to each other. We identified line e40-mum1 carrying a Mu transposon inserted in ZmENOD40-1, the maize gene that has the highest homology to leguminous ENOD40. The insertion causes a dramatic reduction of the

  7. Molecular cloning and functional characterization of the diapause hormone receptor in the corn earworm Helicoverpa zea

    Science.gov (United States)

    The diapause hormone (DH) in the heliothine moth has shown its activity in termination of pupal diapause, while the orthology in the silkworm is known to induce embryonic diapause. In the current study, we cloned the diapause hormone receptor from the corn earworm Helicoverpa zea (HzDHr) and tested ...

  8. Epidemiology of cercarial stage of trematodes in freshwater snails from Chiang Mai province, Thailand

    Institute of Scientific and Technical Information of China (English)

    Thapana Chontananarth; Chalobol Wongsawad

    2013-01-01

    Objective: To investigate the epidemiological situation of cercarial trematodes infection in freshwater snails from different water resources in Chiang Mai province, Thailand. Methods:The snail specimens were collected from 13 districts of Chiang Mai province during April 2008 to February 2012. The prevalence of cercarial infection in snails was investigated using the crushing method. The drawing was done with the help of a camera lucida for the morphological study. Results:A total of 2 479 snail individuals were collected and classified into 7 families, 11 genera, and 14 species, Among them, 8 snails species were found to be infected with an overall prevalence of 17.27% (428/2 479), which infected with nine groups of cercariae;gymnocephalous cercaria, strigea cercaria, megalurous cercaria, monostome cercaria, parapleurolophocercous cercaria (Haplorchis cercaria), pleurolophocercous cercaria, furcocercous cercaria (Transversotrema cercaria), xiphidiocercaria, and virgulate cercaria. The parapleurolophocercous cercaria was found to be the dominant type among the cercarial infection in the snails (64.25%). Conclusions:The various species of snails found in the research location act as the intermediate hosts for the high prevalence of parasitic infection of many species of mammals. This work will provide new information on both the distribution and first intermediate host of trematodes.

  9. A VIVÊNCIA DOS MAIS VELHOS EM UMA COMUNIDADE INDÍGENA GUARANI MBYÁ

    Directory of Open Access Journals (Sweden)

    Filipa Daniela Marques

    2015-08-01

    Full Text Available É possível entender que o aumento de pessoas idosas no mundo requer uma perspectiva transcultural da adultez e da velhice. Assim, este estudo exploratório procurou compreender a dinâmica cultural de uma comunidade indígena, destacando o papel da pessoa mais velha. Para tal foram realizadas entrevistas abertas com roteiro semi-estrurado com seis interlocutores do Conselho de Anciãos do povo Guarani-Mbyá, de uma tradicional aldeia de São Paulo que se dispuseram a participar; e outras informações e impressões foram registradas ao longo da pesquisa num diário de campo. A análise do conteúdo sugeriu que "ser Guarani-Mbyá" é um modo de viver e estar, orientado para a preservação da tradição através da educação e religião; o papel dos mais velhos como guardiões e transmissores das tradições. Os resultados contribuem para olhar o envelhecimento sob outras perspectivas culturais.

  10. Prevalence and Multilocus Genotyping Analysis of Cryptosporidium and Giardia Isolates from Dogs in Chiang Mai, Thailand

    Directory of Open Access Journals (Sweden)

    Sahatchai Tangtrongsup

    2017-05-01

    Full Text Available The occurrence and zoonotic potential of Cryptosporidium spp. and Giardia duodenalis isolated from dogs in Chiang Mai, Thailand were determined. Fecal samples were collected from 109 dogs between July and August 2008. Cryptosporidium spp. infection was determined by immunofluorescent assay (IFA, PCR assays that amplify Cryptosporidium heat-shock protein 70 kDa (hsp70, and two PCR assays that amplify a small subunit-ribosomal RNA (SSU-rRNA. Giardia duodenalis infection was identified using zinc sulfate centrifugal flotation, IFA, and four PCR assays that amplify the Giardia glutamate dehydrogenase (gdh, beta-giardin (bg, and generic and dog-specific assays of triosephosphate isomerase (tpi genes. Overall prevalence of Cryptosporidium spp. and G. duodenalis was 31.2% and 45.9%, respectively. Sequence analysis of 22 Cryptosporidium-positive samples and 21 Giardia-positive samples revealed the presence of C. canis in 15, and C. parvum in 7, G. duodenalis Assemblage C in 8, D in 11, and mixed of C and D in 2 dogs. Dogs in Chiang Mai were commonly exposed to Cryptosporidium spp. and G. duodenalis. Cryptosporidium parvum can be isolated from the feces of dogs, and all G. duodenalis assemblages were dog-specific. Dogs could be a reservoir for a zoonotic Cryptosporidium infection in humans, but further studies will be required to determine the clinical and zoonotic importance.

  11. The Mais Médicos (More Doctors) Program: panorama of the scientific output.

    Science.gov (United States)

    Kemper, Elisandréa Sguario; Mendonça, Ana Valeria Machado; Sousa, Maria Fátima de

    2016-09-01

    Despite the progress achieved by the Primary Health Care and Family Health Strategy in the Unified Health System (SUS) challenges still remain with regard to the universality of access and the quality of services, one of the factors being the unequal distribution of physicians. The Brazilian Government established the Mais Médicos Program (More Doctors Program), in order to move forward in the provision, placement and training of physicians in the SUS. This study consists of a review of the literature of the Mais Médicos Program, in order to map and assess the scientific production on the Program, as well as summarize the findings and present the results of the analysis. Fifty-four publications were selected, which evaluate the Program in terms of effectiveness, analysis of the implementation process, the media and the statements of the actors and assessment of the legal and constitutional precepts. The criticisms and limitations found were also systematically analyzed. With respect to the analysis, evaluations of the Program are overwhelmingly positive, showing important changes in the work processes in services and training. The studies that show the Program as being an important instrument for the effective implementation of the right to health are highlighted.

  12. Standard-based Curriculum Analysis of Teacher Professional in Social Studies, Chiang Mai University

    Directory of Open Access Journals (Sweden)

    Charin Mangkhang

    2017-06-01

    Full Text Available This research aimed to analyze the learning substances and teaching professional competency in bachelor of education program along the professional standard, Chiang Mai University. Studying the teaching professional competency application of the graduates of the social studies program were employed. The target group for the research included 15 graduates finishing the social studies program in academic year 2010-2015. Instruments included the courses on teaching profession, recording group discussion whose results would be analyzed in term of content analysis. The findings revealed that 1 the learning substance and competency of the teaching professional persons was composed of 9 knowledge standards, 69 learning substances, and 33 competencies, 2 graduates of social studies curriculum of Chiang Mai University had teaching professional competency at much in the aspects of being teacher, classroom management, educational measurement and evaluation and curriculum development. The recommendations included there should be the development of the courses on multicultural education, ASEAN studies in school, psychology on special education and evaluation in alternative education.

  13. A aplicabilidade das normas dos direitos humanos vigentes, para uma sociedade mais sustentável

    Directory of Open Access Journals (Sweden)

    Cleiton Lixieski Sell

    2013-11-01

    Full Text Available O objetivo do presente trabalho é tratar sobre a questão da universalização dos direitos humanos fundamentais permeados pela relevância e sua efetivação. Para tal, foram abordadas questões no tocante a normatização, a corrente jus naturalista, bem como com a questão da sustentabilidade propriamente dita. EM um contexto histórico, onde a origem histórica mundial dos direitos humanos foi estabelecida com o advento da Declaração dos Direitos Humanos em 1948. Buscou-se também, questionar a questão de um mínimo ético sustentável, uma vez que, discute-se no âmbito dos direitos humanos e em esfera mundial, que através da Carta Política de 1988, foram resgatados ainda com mais intensidade esses direitos, uma vez que, carregam a ideia de proteção e a garantia da dignidade que lhe foi conferia em texto constitucional. Contudo, começaram a surgir novos paradigmas para atender as necessidades do planeta terra, pois, devido a ação antrópica descontrolada, já não se tem mais o cálculo do grau de gravidade que se encontra o planeta.

  14. Production and characterization of Bacillus thuringiensis Cry1Ac-resistant cotton bollworm Helicoverpa zea (Boddie).

    Science.gov (United States)

    Anilkumar, Konasale J; Rodrigo-Simón, Ana; Ferré, Juan; Pusztai-Carey, Marianne; Sivasupramaniam, Sakuntala; Moar, William J

    2008-01-01

    Laboratory-selected Bacillus thuringiensis-resistant colonies are important tools for elucidating B. thuringiensis resistance mechanisms. However, cotton bollworm, Helicoverpa zea, a target pest of transgenic corn and cotton expressing B. thuringiensis Cry1Ac (Bt corn and cotton), has proven difficult to select for stable resistance. Two populations of H. zea (AR and MR), resistant to the B. thuringiensis protein found in all commercial Bt cotton varieties (Cry1Ac), were established by selection with Cry1Ac activated toxin (AR) or MVP II (MR). Cry1Ac toxin reflects the form ingested by H. zea when feeding on Bt cotton, whereas MVP II is a Cry1Ac formulation used for resistance selection and monitoring. The resistance ratio (RR) for AR exceeded 100-fold after 11 generations and has been maintained at this level for nine generations. This is the first report of stable Cry1Ac resistance in H. zea. MR crashed after 11 generations, reaching only an RR of 12. AR was only partially cross-resistant to MVP II, suggesting that MVP II does not have the same Cry1Ac selection pressure as Cry1Ac toxin against H. zea and that proteases may be involved with resistance. AR was highly cross-resistant to Cry1Ab toxin but only slightly cross-resistant to Cry1Ab expressing corn leaf powder. AR was not cross-resistant to Cry2Aa2, Cry2Ab2-expressing corn leaf powder, Vip3A, and cypermethrin. Toxin-binding assays showed no significant differences, indicating that resistance was not linked to a reduction in binding. These results aid in understanding why this pest has not evolved B. thuringiensis resistance, and highlight the need to choose carefully the form of B. thuringiensis protein used in experiments.

  15. ZEA-TDMA: design and system level implementation of a TDMA protocol for anonymous wireless networks

    Science.gov (United States)

    Banerjee, Debasmit; Dong, Bo; Biswas, Subir

    2013-05-01

    Wireless sensor network used in military applications may be deployed in hostile environments, where privacy and security is of primary concern. This can lead to the formation of a trust-based sub-network among mutually-trusting nodes. However, designing a TDMA MAC protocol is very challenging in situations where such multiple sub-networks coexist, since TDMA protocols require node identity information for slot assignments. This paper introduces a novel distributed TDMA MAC protocol, ZEA-TDMA (Zero Exposure Anonymous TDMA), for anonymous wireless networks. ZEA-TDMA achieves slot allocation with strict anonymity constraints, i.e. without nodes having to exchange any identity revealing information. By using just the relative time of arrival of packets and a novel technique of wireless collision-detection and resolution for fixed packetsizes, ZEA-TDMA is able to achieve MAC slot-allocation which is described as follows. Initially, a newly joined node listens to its one-hop neighborhood channel usage and creates a slot allocation table based on its own relative time, and finally, selects a slot that is collision free within its one-hop neighborhood. The selected slot can however cause hidden collisions with a two-hop neighbor of the node. These collisions are resolved by a common neighbor of the colliding nodes, which first detects the collision, and then resolve them using an interrupt packet. ZEA-TDMA provides the following features: a) it is a TDMA protocol ideally suited for highly secure or strictly anonymous environments b) it can be used in heterogeneous environments where devices use different packet structures c) it does not require network time-synchronization, and d) it is insensitive to channel errors. We have implemented ZEA-TDMA on the MICA2 hardware platform running TinyOS and evaluated the protocol functionality and performance on a MICA2 test-bed.

  16. Photosynthetic Determinants of Growth in Maize Plants: Effects of Nitrogen Nutrition on Growth, Carbon Fixation and Photochemical Features

    OpenAIRE

    S. C., Huber; Tatsuo, SUGIYAMA; R.S, Alberte; Department of Agriculture, Agricultural Research Service; Department of Agricultural Chemistry, Faculty of Agriculture, Tohoku University; Department of Molecular Genetics and Cell Biology, The University of Chicago

    1989-01-01

    Maize (Zea mays L.) plants were grown in a greenhouse with different levels of nitrate-N (2 to 20 millimolar). Nitrogen nutrition had dramatic effects on plant growth and photosynthetic characteristics of mature leaves. Increasing nitrogen resulted in greater biomass production, shoot/root ratios, and rates of leaf expansion during the day. The elongating zone of high-N plants had higher activities (per gram fresh weight) of sucrose synthase and neutral invertase than low-N plants, suggesting...

  17. Effects of a humic acid and its size-fractions on the bacterial community of soil rhizosphere under maize (Zea mays L.).

    Science.gov (United States)

    Puglisi, Edoardo; Fragoulis, George; Ricciuti, Patrizia; Cappa, Fabrizio; Spaccini, Riccardo; Piccolo, Alessandro; Trevisan, Marco; Crecchio, Carmine

    2009-10-01

    The effects of a humic acid (HA) and its size-fractions on plants carbon deposition and the structure of microbial communities in the rhizosphere soil of maize (Zea mays L.) plants were studied. Experiments were conducted in rhizobox systems that separate an upper soil-plant compartment from a lower compartment, where roots are excluded from the rhizosphere soil by a nylon membrane. The upper rhizobox compartment received the humic additions, whereas, after roots development, the rhizosphere soil in the lower compartment was sampled and sliced into thin layers. The lux-marked biosensor Pseudomonas fluorescens 10586 pUCD607 biosensor showed a significant increase in the deposition of bioavailable sources of carbon in the rhizosphere of soils when treated with bulk HA, but no response was found for treatments with the separated size-fractions. PCR-DGGE molecular fingerprintings revealed that the structure of rhizosphere microbial communities was changed by all humic treatments and that the smaller and more bioavailable size-fractions were more easily degraded by microbial activity than the bulk HA. On the other hand, highly hydrophobic and strongly associated humic molecules in the bulk HA required additional plant rhizodeposition before their bio-transformation could occur. This work highlights the importance of applying advanced biological and biotechnological methods to notice changes occurring in plant rhizodeposition and rhizosphere microbial activity. Moreover, it suggests correlations between the molecular properties of humic matter and their effects on microbial communities in the rhizosphere as mediated by root exudation.

  18. Contribution of arbuscular mycorrhizal fungi to the development of maize (Zea mays L.) grown in three types of coal mine spoils.

    Science.gov (United States)

    Guo, Wei; Zhao, Renxin; Fu, Ruiying; Bi, Na; Wang, Lixin; Zhao, Wenjing; Guo, Jiangyuan; Zhang, Jun

    2014-03-01

    Coal mine spoils are usually unfavorable for plant growth and have different properties according to dumping years, weathering degree, and the occurrence of spontaneous combustion. The establishment of plant cover in mine spoils can be facilitated by arbuscular mycorrhizal fungi (AMF). A greenhouse pot experiment was conducted to evaluate the importance of AMF in plant adaptation to different mine spoils and the potential role of AMF for revegetation practices. We investigated the effects of Glomus aggregatum, Rhizophagus intraradices (syn. Glomus intraradices), and Funneliformis mosseae (syn. Glomus mosseae) on the growth, nutritional status, and metal uptake of maize (Zea mays L.) grown in recent discharged (S1), weathered (S2), and spontaneous combusted (S3) coal mine spoils. Symbiotic associations were successfully established between AMF and maize in three substrates. Mycorrhizal colonization effectively promoted plant growth by significantly increasing the uptake of nitrogen (N), phosphorus (P), and potassium (K), adjusting C:N:P stoichiometry and alleviating toxic effects of heavy metals. G. aggregatum, R. intraradices, and F. mosseae exhibited different mycorrhizal effects in response to mine spoil types. F. mosseae was the most effective in the development of maize in S1 and may be the most appropriate for revegetation of this substrate, while R. intraradices played the most beneficial role in S2 and S3. Our results suggest that inoculation with AMF can enhance plant adaptation to different types of coal mine spoils and play a positive role in the revegetation of coal mine spoil banks.

  19. Effect of Piriformospora indica inoculation on root development and distribution of maize (Zea mays L.) in the presence of petroleum contaminated soil

    Science.gov (United States)

    Zamani, Javad; Hajabbasi, Mohammad Ali; Alaie, Ebrahim

    2014-05-01

    The root systems of most terrestrial plants are confronted to various abiotic and biotic stresses. One of these abiotic stresses is contamination of soil with petroleum hydrocarbon, which the efficiency of phytoremediation of petroleum hydrocarbons in soils is dependent on the ability of plant roots to development into the contaminated soils. Piriformospora indica represents a recently discovered fungus that transfers considerable beneficial impact to its host plants. A rhizotron experiment was conducted to study the effects of P. Indica inoculation on root distribution and root and shoot development of maize (Zea mays L.) in the presence of three patterns of petroleum contamination in the soil (subsurface contamination, continuous contamination and without contamination (control)). Root distribution and root and shoot development were monitored over time. The final root and shoot biomass and the final TPH concentration in the rhizosphere were determined. Analysis of digitized images which were prepared of the tracing of the appeared roots along the front rhizotrons showed the depth and total length of root network in the contamination treatments were significantly decreased. Although the degradation of TPH in the rhizosphere of maize was significant, but there were no significant differences between degradation of TPH in the rhizosphere of +P. indica plants in comparison to -P. indica plants.

  20. Slow release chelate enhancement of lead phytoextraction by corn (Zea mays L.) from contaminated soil--a preliminary study.

    Science.gov (United States)

    Li, Haifeng; Wang, Qingren; Cui, Yanshan; Dong, Yiting; Christie, Peter

    2005-03-01

    Short-term enhancement of lead (Pb) and zinc (Zn) uptake by corn (Zea mays L.) seedlings from a contaminated soil was compared using slow-release coated EDTA granules-a coated chelating agent (CCA), uncoated EDTA granules, and EDTA solution in a greenhouse experiment. Soil Pb and Zn fractions were determined using a sequential extraction scheme. Release of the metals in the soil was examined in a column leaching study. After only 7 days of seedling growth, shoot biomass was decreased by all EDTA treatments compared with the zero-EDTA control. The amount of shoot biomass produced was highest with uncoated EDTA, intermediate with CCA, and lowest with the EDTA solution. Shoot Pb contents were highest with solid EDTA, intermediate with CCA, and lowest with EDTA solution, and they were always higher with EDTA treatments than in controls. In contrast, shoot Zn contents following EDTA treatments were lower than in the control. Levels of soil dissolved organic carbon (DOC) in aqueous soil extracts were much lower after CCA application than following treatments with solid EDTA and EDTA solution. After 17 days of plant growth, when most of the chelating agent had been released from the CCA, soil organic carbon levels remained relatively constant and similar to those in the control, indicating that a relatively low chelating agent concentration can be maintained for the plants to take up the metals. The distribution of Pb in the sequential extraction procedure showed that the Pb level in the exchangeable+carbonate-bound fraction with CCA was significantly lower than that with solid EDTA or EDTA solution, further indicating that slow release of CCA improves the bioavailability of metals in the soil to match plant uptake of those metals. The results suggest that CCA can enhance shoot content of Pb but not of Zn from the contaminated soil in the short term, and may also reduce the risk of metal leaching from the soil.

  1. Chromosomal locations of the maize (Zea mays L. HtP and rt genes that confer resistance to Exserohilum turcicum

    Directory of Open Access Journals (Sweden)

    Juliana Bernardi Ogliari

    2007-01-01

    Full Text Available We used 125 microsatellite markers to genotype the maize (Zea mays L. near isogenic lines (NIL L30HtPHtPRtRt and L30htphtpRtRt and the L40htphtprtrt line which contrast regarding the presence of the recently described dominant HtP and the recessive rt genes that confer resistance to Exserohilum turcicum. Five microsatellite markers revealed polymorphisms between the NIL and were considered candidate linked markers for the HtP resistance gene. Linkage was confirmed by bulked segregant sample (BSS analysis of 32 susceptible and 34 resistant plants from a BC1F1 population derived from the cross (L30HtPHtPRtRt x L40htphtprtrt x L40htphtprtrt. The bnlg198 and dupssr25 markers, both located on maize chromosome 2L (bin 2.08, were polymorphic between bulks. Linkage distances were estimated based on co-segregation data of the 32 susceptible plants and indicated distances of 28.7 centimorgans (cM between HtP and bnlg198 and 23.5 cM between HtP and dupssr25. The same set of susceptible plants was also genotyped with markers polymorphic between L30HtPHtPRtRt and L40htphtprtrt in order to find markers linked to the rt gene. Marker bnlg197, from chromosome 3L (bin 3.06, was found linked to rt at a distance of 9.7 cM. This is the first report on the chromosomal locations of these newly described genes.

  2. Biology and natural enemies of Peregrinus maidis (Ashmead in corn (Zea mays L., in systems of polycrops

    Directory of Open Access Journals (Sweden)

    Marcos Tulio García González

    2015-02-01

    Full Text Available This research was done in Fomento municipality, Sancti Spíritus, in Cuba, from 2011 through 2013 in two ecosystems and in two sowing times (rainy and dry seasons. The objectives were to describe the life cycle of Peregrinus maidis (Ashmead and the damage caused to corn (Zea mays L., to identify the main pest bio-regulators naturally occurring in two agro-ecosystems, and to determine the predator-prey relationship. The experiment was arranged in a randomized block design. The data were collected through observation at weekly intervals. In order to estimate the number of pest insects and bio-regulators occurring on the plants, 25 plants per parcel were selected for a total of 100 plants per treatment (maize/squash, maize/beans, maize/ Sesame, maize/sunflower, and maize monoculture. Once the research was accomplished, it was concluded that P maidis had been present since the first week, and reached its population peak in week six. The lower indexes of affectation occurred in the pre-mountain agro-ecosystems, and with more frequency in the maize/sesame and maize/squash polyculture, which depended on the time of the year and the season. Fifteen species of P. maidis control insects of were identified, and Scymnus sp was found in all treatments. The life cycle of P maidis averaged 5.4 days more in the dry season than in rain season. The predator-prey relationship showed relatively superior indexes in the polyculture systems than in monocrops systems.

  3. Uptake of atrazine and cadmium from soil by maize (Zea mays L.) in association with the arbuscular mycorrhizal fungus Glomus etunicatum.

    Science.gov (United States)

    Huang, Honglin; Zhang, Shuzhen; Chen, Bao-Dong; Wu, Naiying; Shan, Xiao-Quan; Christy, Peter

    2006-12-13

    A greenhouse pot experiment was carried out to investigate the effect of the arbuscular mycorrhizal fungus Glomus etunicatum on the uptake of atrazine (ATR) and cadmium (Cd) from soil by maize (Zea mays L.). Mycorrhizal colonization led to an increase in the accumulation of Cd and ATR in maize roots but a decrease in the shoots. Atrazine alleviated the adverse effects of Cd on maize growth, and this was more pronounced in the inoculated plants. An increase in Cd accumulation by maize roots was observed when ATR was also present. After harvest, the residual ATR concentration in the soil decreased markedly. With mycorrhizal inoculation the amount of residual ATR decreased more in the bulk soil but less in the rhizosphere soil compared to the noninoculated controls. Cadmium application significantly decreased the ATR residual concentrations in both the rhizosphere and bulk soils irrespective of inoculation treatment.

  4. Characterization of ApB73, a virulence factor important for colonization of Zea mays by the smut Ustilago maydis.

    Science.gov (United States)

    Stirnberg, Alexandra; Djamei, Armin

    2016-12-01

    The biotrophic fungus Ustilago maydis, the causal agent of corn smut disease, uses numerous small secreted effector proteins to suppress plant defence responses and reshape the host metabolism. However, the role of specific effectors remains poorly understood. Here, we describe the identification of ApB73 (Apathogenic in B73), an as yet uncharacterized protein essential for the successful colonization of maize by U. maydis. We show that apB73 is transcriptionally induced during the biotrophic stages of the fungal life cycle. The deletion of the apB73 gene results in cultivar-specific loss of gall formation in the host. The ApB73 protein is conserved among closely related smut fungi. However, using virulence assays, we show that only the orthologue of the maize-infecting head smut Sporisorium reilianum can complement the mutant phenotype of U. maydis. Although microscopy shows that ApB73 is secreted into the biotrophic interface, it seems to remain associated with fungal cell wall components or the fungal plasma membrane. Taken together, the results show that ApB73 is a conserved and important virulence factor of U. maydis that localizes to the interface between the pathogen and its host Zea mays.

  5. Improved tolerance of maize (Zea mays L.) to heavy metals by colonization of a dark septate endophyte (DSE) Exophiala pisciphila.

    Science.gov (United States)

    Li, T; Liu, M J; Zhang, X T; Zhang, H B; Sha, T; Zhao, Z W

    2011-02-15

    Dark septate endophytes (DSE) are ubiquitous and abundant in stressful environments including heavy metal (HM) stress. However, our knowledge about the roles of DSE in improving HM tolerance of their host plants is poor. In this study, maize (Zea mays L.) was inoculated with a HM tolerant DSE strain Exophiala pisciphila H93 in lead (Pb), zinc (Zn), and cadmium (Cd) contaminated soils. E. pisciphila H93 successfully colonized and formed typical DSE structures in the inoculated maize roots. Colonization of E. pisciphila H93 alleviated the deleterious effects of excessive HM supplements and promoted the growth of maize (roots and shoots) under HM stress conditions, though it significantly decreased the biomass of inoculated maize under no HM stress. Further analysis showed that the colonization of E. pisciphila H93 improved the tolerance of maize to HM by restricting the translocation of HM ions from roots to shoots. This study demonstrated that under higher HM stress, such a mutual symbiosis between E. pisciphila and its host (maize) may be an efficient strategy to survive in the stressful environments.

  6. Cysteine- and glutathione-mediated uptake of lead and cadmium into Zea mays and Brassica napus roots

    Energy Technology Data Exchange (ETDEWEB)

    Vadas, Timothy M., E-mail: tvadas@umbc.ed [Department of Biological and Environmental Engineering, Cornell University, 320 Riley-Robb Hall, Ithaca, NY 14853 (United States); Ahner, Beth A., E-mail: baa7@cornell.ed [Department of Biological and Environmental Engineering, Cornell University, 320 Riley-Robb Hall, Ithaca, NY 14853 (United States)

    2009-08-15

    This study examines a new mechanism for the uptake of Pb and Cd into Brassica napus and Zea mays roots. During hydroponic experiments, the uptake of Pb and Cd was enhanced in the presence of cysteine and glutathione, whereas no or very low uptake was observed in EDTA and penicillamine controls. Uptake rates were also enhanced after pre-exposure to cysteine or glutathione and inhibited in the presence of vanadate, suggesting a biological mechanism of uptake. Increasing concentrations of glutathione in solution resulted in decreasing Pb uptake rates, indicating competition for transport between free-glutathione and Pb-glutathione species. Pb uptake in the presence of increasing cysteine concentrations resulted in decreased uptake initially but linearly increasing uptake at higher concentrations. Experimentation showed concentration dependent Pb uptake rates. We speculate that there are specific transporters for these thiol ligands and describe what barriers remain for application of this novel transport mechanism in chelator-assisted phytoremediation. - Cysteine and glutathione mediate the transport of lead and cadmium into plant roots.

  7. Effects of Liquid Organic Fertilizer on Time of Tasselling, Time of Silking and Grain Yield of Maize (Zea mays

    Directory of Open Access Journals (Sweden)

    Enujeke, E. C. and Ojeifo, I. M.

    2013-04-01

    Full Text Available A study was carried out in the Teaching and Research Farm of Delta State University, Asaba Campus from August to December in 2005 and repeated between March and July, 2006 to evaluate the response of maize (Zea mays to liquid organic fertilizer. The study was conducted using a split plot fitted into randomized complete block design. Liquid organic fertilizer was diluted at the rate of 60 ml of the product to 15 litres of water and applied to maize foliage, topsoil, foliage and topsoil at the rates of 5l/ha, 10l/ha, 151/ha, l8l/ha, 201/ha and 251/ha. The result obtained indicated a positive influence of liquid organic fertilizer on time of tasselling, time of silking and grain yield of maize. Liquid organic fertilizer significantly reduced the times of tasselling and silking, and increased grain yield of maize. Based on this study, it is recommended that 151/ha of liquid organic fertilizer which produced 5.6tha’ in 2005 and 6.1tha’ of dry grain yield 2006 be applied on the topsoil of maize plant with a view to maximally exploit the great economic potentials of the crop.

  8. Comparison of Three Methods for Determination of Root Hydraulic Conductivity of Maize (Zea mays L.) Root System

    Institute of Scientific and Technical Information of China (English)

    LI Qing-ming; LIU Bin-bin

    2010-01-01

    Three techniques of root pressure probe,pressure chamber and high pressure flow meter were used to measure the hydraulic conduetivities (Lp,) of whole root systems of young maize (Zea mays L.) seedlings grown hydroponically under either drought or normal water conditions.Compared to normal water conditions,drought stress simulated by polyethylene glycol 6 000 (osmotic potential=-0.2 MPa) reduced Lp,in the root system by over 50%.It indicated that water permeability in the roots decreased significantly when plants suffered from water shortages.Moreover,there was no significant difference (P<0.05) on the Lpr values in the root systems developed under a given water stress regime among the three techniques used.Therefore,all three methods are acceptable to study the hydraulic conductivity of maize seedling root systems.We have also highlighted some of the technical limitations of each method.It can be inferred that the root pressure probe is preferable for young maize seedlings because it is subtle and has the additional ability to determine solute transport properties,but the method is time consuming.Other advantages and disadvantages of each technique are discussed in order to acquaint researchers with basic information that could contribute to their choice of an appropriate technique for future studies.

  9. Alternative Splicing and Differential Expression of Two Transcripts of Nicotine Adenine Dinucleotide Phosphate Oxidase B Gene from Zea mays

    Institute of Scientific and Technical Information of China (English)

    Fan Lin; Yun Zhang; Ming-Yi Jiang

    2009-01-01

    With the exception of rice, little is known about the existence of respiratory burst oxidase homolog (rboh) gene in cereals. The present study reports the cloning and analysis of a novel rboh gene, termed ZmrbohB, from maize (Zea mays L.). The full-length cDNA of ZmrbohB encodes a 942 amino acid protein containing all of the respiratory burst oxidase homolog catalytically critical motifs.Altemative splicing of ZmrbohB has generated two transcript isoforms, ZmrbohB-α and -β. Spliced transcript ZmrbohB-β retains an unspliced intron 11 that carries a premature termination codon and probably leads to nonsense-mediated mRNA decay. Expression analysis showed that two splice isoforms were differentially expressed in various tissues and at different developmental stages, and the major product was ZmrbohB-α. The transcripts of ZmrbohB-α accumulated markedly when the maize seedlings were subjected to various abiotic stimuli, such as wounding, cold (4℃), heat (40℃), UV and salinity stress. In addition, several abiotic stimuli also affected the alternative splicing pattern of ZmrbohB except wounding. These results provide new insight into roles in the expression regulation of plant rboh genes and suggest that ZmrbohB gene may play a role in response to environmental stresses.

  10. Root growth, secondary root formation and root gravitropism in carotenoid-deficient seedlings of Zea mays L

    Science.gov (United States)

    Ng, Y. K.; Moore, R.

    1985-01-01

    The effect of ABA on root growth, secondary-root formation and root gravitropism in seedlings of Zea mays was investigated by using Fluridone-treated seedlings and a viviparous mutant, both of which lack carotenoids and ABA. Primary roots of seedlings grown in the presence of Fluridone grew significantly slower than those of control (i.e. untreated) roots. Elongation of Fluridone-treated roots was inhibited significantly by the exogenous application of 1 mM ABA. Exogenous application of 1 micromole and 1 nmole ABA had either no effect or only a slight stimulatory effect on root elongation, depending on the method of application. The absence of ABA in Fluridone-treated plants was not an important factor in secondary-root formation in seedlings less than 9-10 d old. However, ABA may suppress secondary-root formation in older seedlings, since 11-d-old control seedlings had significantly fewer secondary roots than Fluridone-treated seedlings. Roots of Fluridone-treated and control seedlings were graviresponsive. Similar data were obtained for vp-9 mutants of Z. mays, which are phenotypically identical to Fluridone-treated seedlings. These results indicate that ABA is necessary for neither secondary-root formation nor for positive gravitropism by primary roots.

  11. Environmental materials for remediation of soils contaminated with lead and cadmium using maize (Zea mays L.) growth as a bioindicator.

    Science.gov (United States)

    Shi, Yu; Huang, Zhanbin; Liu, Xiujie; Imran, Suheryani; Peng, Licheng; Dai, Rongji; Deng, Yulin

    2016-04-01

    Heavy metal pollution is a severe environmental problem. Remediation of contaminated soils can be accomplished using environmental materials that are low cost and environmentally friendly. We evaluated the individual and combination effects of humic acid (HA), super absorbent polymer (SAP), zeolite (ZE), and fly ash composites (FC) on immobilization of lead (Pb) and cadmium (Cd) in contaminated soils. We also investigated long-term practical approaches for remediation of heavy metal pollution in soil. The biochemical and morphological properties of maize (Zea mays L.) were selected as biomarkers to assess the effects of environmental materials on heavy metal immobilization. The results showed that addition of test materials to soil effectively reduced heavy metal accumulation in maize foliage, improving chlorophyll levels, plant growth, and antioxidant enzyme activity. The test materials reduced heavy metal injury to maize throughout the growth period. A synergistic effect from combinations of different materials on immobilization of Pb and Cd was determined based on the reduction of morphological and biochemical injuries to maize. The combination of zeolite and humic acid was especially effective. Treatment with a combination of HA + SAP + ZE + FC was superior for remediation of soils contaminated with high levels of Pb and Cd.

  12. Potential of kenaf (Hibiscus cannabinus L.) and corn (Zea mays L.) for phytoremediation of dredging sludge contaminated by trace metals.

    Science.gov (United States)

    Arbaoui, Sarra; Evlard, Aricia; Mhamdi, Mohamed El Wafi; Campanella, Bruno; Paul, Roger; Bettaieb, Taoufik

    2013-07-01

    The potential of kenaf (Hibiscus cannabinus L.) and corn (Zea mays L.) for accumulation of cadmium and zinc was investigated. Plants have been grown in lysimetres containing dredging sludge, a substratum naturally rich in trace metals. Biomass production was determined. Sludge and water percolating from lysimeters were analyzed by atomic absorption spectrometry. No visible symptoms of toxicity were observed during the three- month culture. Kenaf and corn tolerate trace metals content in sludge. Results showed that Zn and Cd were found in corn and kenaf shoots at different levels, 2.49 mg/kg of Cd and 82.5 mg/kg of Zn in kenaf shoots and 2.1 mg/kg of Cd and 10.19 mg/kg in corn shoots. Quantities of extracted trace metals showed that decontamination of Zn and Cd polluted substrates is possible by corn and kenaf crops. Tolerance and bioaccumulation factors indicated that both species could be used in phytoremediation.

  13. Arsenic species in broiler (Gallus gallus domesticus) litter, soils, maize (Zea mays L.), and groundwater from litter-amended fields.

    Science.gov (United States)

    D'Angelo, Elisa; Zeigler, Georgia; Beck, E Glenn; Grove, John; Sikora, Frank

    2012-11-01

    Manure and bedding material (litter) generated by the broiler industry (Gallus gallus domesticus) often contain high levels of arsenic (As) when organoarsenical roxarsone and p-arsanilic acid are included in feed to combat disease and improve weight gain of the birds. This study was conducted to determine As levels and species in litter from three major broiler producing companies, and As levels in soils, corn tissue (Zea mays L.), and groundwater in fields where litter was applied. Total As in litter from the three different integrators ranged between bioavailable As (extractable with Mehlich 3 solution and taken up by corn leaves). Arsenic concentrations in plant tissue and groundwater, however, were below the World Health Organization thresholds, which was attributed to strong sorption/precipitation of arsenate in Fe- and Al-rich soils. Ecological impacts of amending soils with As-laden litter depend on the As species in the litter, and chemical and physical properties of soil that strongly affect As mobility and bioavailability in the environment. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. The Effects of Urea Fertilizer and Azotobacter and Azospirillum on Physiological Charactestis of Maize (Zea mays L. at Khash, Iran

    Directory of Open Access Journals (Sweden)

    A Soleymanifard

    2014-10-01

    Full Text Available To study the effects of urea fertilizer and bio-fertilizers on grain yield and important agronomic traits in maize (Zea mays L. Sc704, a split plot experiment based on randomized complete block design with three replications was conducted in Payame Noor University of Khash Research Field during 2011-2012 cropping season. Four different levels of urea consisting of zero, 25% (equal to 87.5 kg.ha-1, 50% (equal to 175 kg.ha-1 and 100% (equal to 350 kg.ha-1 based on the results of soil analysis were assigned to main plot and bio-fertilzers, including Azotobacter, Azospirillum and non- inoculation, to sub plot. Results indicated that nitrogen fertilizer affected the traits under study significantly. The highest and lowest plant height, the number of seed per ear row, the number of grain per row, ears.m-2, 1000 kernel weight, seed yield, bilogocal yield and seed protein content were obtained by using 100% nitrogen fertilizer and control (zero level of urea respectively. Using bio-feretlizers also had a significant effect on traits under study. Bio-fertilizer had positive effect on seed yield and yield components. Thus, there was a seed yield increase of 8.4% and 8.2% by using Azotobacter and Azospirillum compared to the non- inoculated seeds, respectively.

  15. Molecular evolution and gene expression differences within the HD-Zip transcription factor family of Zea mays L.

    Science.gov (United States)

    Mao, Hude; Yu, Lijuan; Li, Zhanjie; Liu, Hui; Han, Ran

    2016-04-01

    Homeodomain-leucine zipper (HD-Zip) transcription factors regulate developmental processes and stress responses in plants, and they vary widely in gene number and family structure. In this study, 55 predicted maize HD-Zip genes were systematically analyzed with respect to their phylogenetic relationships, molecular evolution, and gene expression in order to understand the functional diversification within the family. Phylogenetic analysis of HD-Zip proteins from Zea mays, Oryza sativa, Arabidopsis thaliana, Vitis vinifera, and Physcomitrella patens showed that they group into four classes. We inferred that the copy numbers of classes I and III genes were relatively conserved in all five species. The 55 maize HD-Zip genes are distributed randomly on the ten chromosomes, with 15 segmental duplication and 4 tandem duplication events, suggesting that segmental duplications were the major contributors in the expansion of the maize HD-Zip gene family. Expression analysis of the 55 maize HD-Zip genes in different tissues and drought conditions revealed differences in the expression levels and patterns between the four classes. Promoter analysis revealed that a number of stress response-, hormone response-, light response-, and development-related cis-acting elements were present in their promoters. Our results provide novel insights into the molecular evolution and gene expression within the HD-Zip gene family in maize, and provide a solid foundation for future functional study of the HD-Zip genes in maize.

  16. Improved high-performance liquid chromatography (HPLC) method for qualitative and quantitative analysis of allantoin in Zea mays.

    Science.gov (United States)

    Haghi, Ghasem; Arshi, Rohollah; Safaei, Alireza

    2008-02-27

    A high-performance liquid chromatography (HPLC) method for the qualitative and quantitative analysis of allantoin in silk and seed of Zea mays has been developed. Allantoin separation in crude extract was achieved using a C 18 column and phosphate buffer solution (pH 3.0) as a mobile phase at ambient temperature at a flow rate of 1.0 mL/min and detected at 210 nm. The results showed that the amount of allantoin in samples was between 14 and 271 mg/100 g of dry plant material. A comprehensive validation of the method including sensitivity, linearity, repeatability, and recovery was conducted. The calibration curve was linear over the range of 0.2-200 microg/mL with a correlation coefficient of r2>0.999. Limit of detection (LOD, S/N=3) and limit of quantification (LOQ) values of the allantoin were 0.05 and 0.2 microg/mL (1.0 and 4.0 ng) respectively. The relative standard deviation (RSD) value of the repeatability was reported within 1.2%. The average recovery of allantoin added to samples was 100.6% with RSD of 1.5%.

  17. Agrobacterium-mediated transformation of maize (Zea mays) with Cre-lox site specific recombination cassettes in BIBAC vectors.

    Science.gov (United States)

    Vega, Juan M; Yu, Weichang; Han, Fangpu; Kato, Akio; Peters, Eric M; Zhang, Zhanyuan J; Birchler, James A

    2008-04-01

    The Cre/loxP site-specific recombination system has been applied in various plant species including maize (Zea mays) for marker gene removal, gene targeting, and functional genomics. A BIBAC vector system was adapted for maize transformation with a large fragment of genetic material including a herbicide resistance marker gene, a 30 kb yeast genomic fragment as a marker for fluorescence in situ hybridization (FISH), and a 35S-lox-cre recombination cassette. Seventy-five transgenic lines were generated from Agrobacterium-mediated transformation of a maize Hi II line with multiple B chromosomes. Eighty-four inserts have been localized among all 10 A chromosome pairs by FISH using the yeast DNA probe together with a karyotyping cocktail. No inserts were found on the B chromosomes; thus a bias against the B chromosomes by the Agrobacterium-mediated transformation was revealed. The expression of a cre gene was confirmed in 68 of the 75 transgenic lines by a reporter construct for cre/lox mediated recombination. The placement of the cre/lox site-specific recombination system in many locations in the maize genome will be valuable materials for gene targeting and chromosome engineering.

  18. Milk line as an indicator of the harvesting time of three hybrid seeds of corn (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Célio Trzeciak dos Santos

    2005-03-01

    Full Text Available The experiment was carried out to evaluate the time for harvesting seeds of three hybrids of corn (Zea mays L. at their best physiological quality and the use of the milk line as an indicator of the physiological seed maturity. Single hybrids CD 1723 and CD 5501 and double hybrid OC 705 seeds were collected for 59 days, every four days, starting 23 days after female flowering. Seed dry weight, moisture content, germination, vigour (cold and accelerated aging tests, black layer formation and seed milk line development were analysed. The harvesting time started 47 days after female flowering with high physiological quality of the seeds identified by a joint analysis of those seven characteristics of them. The milk line at stage 4 proved to be the best indicator of the time to harvest corn seeds for maximum physiological quality, because different stages of milk line development in corn seeds could be easily identified in the filed without any special equipment.O experimento foi conduzido durante o ano agrícola de 1996/97 em área experimental da Cooperativa de Desenvolvimento Econômico e Tecnológico (Coodetec, em Cascavel, Paraná, com o objetivo de avaliar o efeito da época de colheita de três híbridos de milho (Zea mays L. na qualidade fisiológica das sementes e o uso da linha de solidificação do endosperma como indicativo da maturidade fisiológica das sementes. O plantio foi realizado em 30 de setembro de 1996. Amostras de sementes dos híbridos simples CD 1723 e CD 5501, bem como do híbrido duplo OC 705, foram colhidas em intervalos de quatro dias, durante 59 dias, iniciando-se a colheita no vigésimo terceiro dia após o florescimento feminino. As características avaliadas nas sementes foram o acúmulo de matéria seca, o conteúdo de umidade, a germinação, o vigor (pelos testes de frio e de envelhecimento acelerado, a formação da camada preta e o desenvolvimento da linha de solidificação do endosperma. A colheita dos tr

  19. A comparison of canopy evapotranspiration between perennial rhizomatous grasses and Zea mays

    Science.gov (United States)

    Hickman, G.; Bernacchi, C.; Dohleman, F.

    2008-12-01

    Perennial rhizomatous C4 grasses are currently considered one of the most promising vegetation types to accommodate a cellulosic feedstock based liquid fuel economy. The current focus on using these vegetation types as a source of renewable fuel has sparked numerous concerns associated with environmental impacts. Of particular interest is the impact that altering the composition of vegetation at the landscape scale would have on local and regional hydrological cycles. We hypothesize that evapotranspiration, ET, will be higher for perennial grasses relative to maize as a result higher leaf area, higher above-ground biomass and prolonged growing seasons. To test this hypothesis, a technique in which ET is estimated as the residual in the energy balance equation from measurements of net radiation and sensible and latent heat fluxes was employed. Measurements were made during the 2007 growing season for three replicate plots of the perennial rhizomatous grasses Miscanthus giganteus and Panicum virgatum, as well as for Zea mays planted at the University of Illinois South Farms. When averaged across the entire growing season, ET for M. giganteus was double relative to Z. mays, and 130% of P. virgatum ET. When compared over the periods in which all three species experienced mature and closed canopies (from day of year 200 to 250), M. giganteus still showed higher rates of ET compared with Z. mays, however, the increase was only ~15%. We conclude that ET associated with perennial alternative energy crops are higher relative to annual row crop; with most ET disparity, particularly for P. virgatum, being driven by phenology, quicker canopy closure and a prolonged growing season. Physiological rates of ET were highest for M. giganteus, followed by Z. mays, followed P. virgatum. Differences in phenology were more important than those of physiology for ET overshadowing effects from increased biomass associated with M. giganteus and/or a physiological difference between these

  20. Programa Mais Médicos: panorama da produção científica

    Directory of Open Access Journals (Sweden)

    Elisandréa Sguario Kemper

    Full Text Available Resumo Apesar dos avanços conquistados pela Atenção Primária e Estratégia Saúde da Família no SUS, ainda persistem desafios com relação à universalização do acesso e à qualidade dos serviços, tendo como um dos fatores a defasagem e a distribuição desigual de médicos. O Governo brasileiro propôs o Programa Mais Médicos (PMM para o Brasil, considerado como um conjunto de medidas para avançar no provimento, fixação e formação de médicos no SUS. Este estudo consiste em uma revisão bibliográfica do Programa Mais Médicos, com o objetivo de mapear e dimensionar a produção científica sobre o mesmo, bem como sistematizar os achados e apresentar os resultados a partir de uma análise crítica. Foram selecionadas 54 publicações, as quais avaliam o Programa Mais Médicos em termos de efetividade, de análise do processo de implantação, de análise da mídia e dos discursos de atores, da formação e da análise jurídica e constitucional. Foram também sistematizadas as críticas e as limitações encontradas. Com relação à análise, de forma geral, as avaliações do Programa são positivas, apresentando mudanças importantes no processo de trabalho nos serviços e na formação. Destaque para os estudos que apontam o Programa como um importante instrumento para a efetivação do direito à saúde.

  1. Implementation of integrated heterogeneous electronic electrocardiography data into Maharaj Nakorn Chiang Mai Hospital Information System.

    Science.gov (United States)

    Khumrin, Piyapong; Chumpoo, Pitupoom

    2016-03-01

    Electrocardiography is one of the most important non-invasive diagnostic tools for diagnosing coronary heart disease. The electrocardiography information system in Maharaj Nakorn Chiang Mai Hospital required a massive manual labor effort. In this article, we propose an approach toward the integration of heterogeneous electrocardiography data and the implementation of an integrated electrocardiography information system into the existing Hospital Information System. The system integrates different electrocardiography formats into a consistent electrocardiography rendering by using Java software. The interface acts as middleware to seamlessly integrate different electrocardiography formats. Instead of using a common electrocardiography protocol, we applied a central format based on Java classes for mapping different electrocardiography formats which contains a specific parser for each electrocardiography format to acquire the same information. Our observations showed that the new system improved the effectiveness of data management, work flow, and data quality; increased the availability of information; and finally improved quality of care.

  2. Micro-components survey of residential indoor water consumption in Chiang Mai

    Directory of Open Access Journals (Sweden)

    T. Aramaki

    2008-08-01

    Full Text Available The direct measurement of the micro-components of water consumption (i.e., consumption by each residential activity, such as toilet-, laundry-, bath-, and kitchen-use, both in the dry season and in the rainy season, was conducted in Chiang Mai, Thailand. It was expected that rainfall differences between the dry and rainy season would influence awareness for water resources so that water consumption in the dry season would be smaller than that in the rainy season. In addition, it was examined whether the differences in water resources such as public waterworks or non-public waterworks (i.e., community waterworks, mountainous water and groundwater, affected the amount of water use. A small-sized accumulative water meter was developed for measurement. This survey provides important information for water demand estimations and water supply planning in middle-developed countries where water consumption is expected to increase in future.

  3. Micro-components survey of residential indoor water consumption in Chiang Mai

    Directory of Open Access Journals (Sweden)

    T. Aramaki

    2008-02-01

    Full Text Available The direct measurement of the micro-components of water consumption (i.e., consumption by each residential activity, such as toilet, laundry, bath, and kitchen both in the dry season and in the rainy season was conducted in Chiang Mai, Thailand. It was expected that rainfall differences between the dry and rainy season could influence awareness for water resources so that water consumption in the dry season may be smaller than that in the rainy season. It was also examined that whether the differences in water resources such as public waterworks or non-public waterworks like community waterworks, mountainous water and groundwater, affect the water use amount. A small-sized accumulative water meter was developed for measurement. This survey can provide the important information for water demand estimation and water supply planning in middle-developed countries where their water consumption should be expected to increase from here on.

  4. Mai 68, les avatars d’une posture générationnelle

    Directory of Open Access Journals (Sweden)

    Sarah Sindaco

    2011-01-01

    Full Text Available Mai 68 est aujourd’hui largement considéré d’une part comme une révolution culturelle, d’autre part comme un phénomène générationnel : dans les représentations, et particulièrement dans le discours commémoratif actuel, les évènements de 68 sont souvent réduits à la révolte de la jeunesse étudiante parisienne, à son refus de l’autorité, à ses revendications en matière d’autonomie individuelle et de liberté sexuelle. En effet, le terme de génération lui-même revient de façon presque systématiqu...

  5. Culture and subjectivity – areas of continuity and rupture: the history of Mukhtar Mai

    Directory of Open Access Journals (Sweden)

    Jennifer Perroni

    2009-07-01

    Full Text Available In 2002 a Pakistani woman named Mukhtar Mai was sentenced to collective rape for a crime committed by her brother. Unfortunately, situations like these cannot be considered rare in Pakistan, where rape as a way of resolving conflicts between families is a common practice. Consequently, the most remarkable aspect of this story may have been the reaction of this woman, who instead of resigning herself to silence or committing suicide, which is common in these cases, initiated a campaign of protest and struggle in favor of women’s rights in her country. Through this story we can perceive how tradition and culture permeate the actions and representations of a people in which the femail body still represents an object that can be used for the honor or shame of the clan. But this system of values also makes possible the rise of indivuduals who are able to break with a pattern of subordination.

  6. Bunch compression efficiency of the femtosecond electron source at Chiang Mai University

    Energy Technology Data Exchange (ETDEWEB)

    Thongbai, C. [Department of Physics and Materials Science, Chiang Mai University, Chiangmai 50200 (Thailand); ThEP Center, Commission on Higher Education, Ministry of Education, Bangkok 10400 (Thailand); Kusoljariyakul, K., E-mail: zartparz@gmail.com [Department of Physics and Materials Science, Chiang Mai University, Chiangmai 50200 (Thailand); ThEP Center, Commission on Higher Education, Ministry of Education, Bangkok 10400 (Thailand); Saisut, J. [Department of Physics and Materials Science, Chiang Mai University, Chiangmai 50200 (Thailand); ThEP Center, Commission on Higher Education, Ministry of Education, Bangkok 10400 (Thailand)

    2011-07-21

    A femtosecond electron source has been developed at the Plasma and Beam Physics Research Facility (PBP), Chiang Mai University (CMU), Thailand. Ultra-short electron bunches can be produced with a bunch compression system consisting of a thermionic cathode RF-gun, an alpha-magnet as a magnetic bunch compressor, and a linear accelerator as a post acceleration section. To obtain effective bunch compression, it is crucial to provide a proper longitudinal phase-space distribution at the gun exit matched to the subsequent beam transport system. Via beam dynamics calculations and experiments, we investigate the bunch compression efficiency for various RF-gun fields. The particle distribution at the RF-gun exit will be tracked numerically through the alpha-magnet and beam transport. Details of the study and results leading to an optimum condition for our system will be presented.

  7. Como diagnosticar as quatro causas mais freqüentes de demência?

    OpenAIRE

    Caramelli Paulo; Barbosa Maira Tonidandel

    2002-01-01

    Doença de Alzheimer, demência vascular, demência com corpos de Lewy e demência frontotemporal são as quatro causas mais freqüentes de demência na prática clínica. O diagnóstico diferencial dessas condições se baseia na busca de perfis clínicos característicos por anamnese adequada, exame neurológico e avaliação neuropsicológica, além de investigação complementar pertinente, que consiste em exames laboratoriais e de neuroimagem. O presente artigo apresenta breve revisão das características pri...

  8. Factors influencing dietary supplement consumption: A case study in Chiang Mai, Thailand

    Directory of Open Access Journals (Sweden)

    Wiwat Wangcharoen

    2013-04-01

    Full Text Available A consumer survey on dietary supplement consumption was carried out on 494 consumers aged 20 years and older in Chiang Mai province. The percentage of consumers who regularly consumed dietary supplements was 38.5%. Vitamins and minerals were the most consumed products, followed by functional drinks, functional foods, protein extracts, dietary fibre, cod liver oil, phytochemicals, algae products, fat absorbers, fish oils and bee products in that order. Females and participants who had recommended waistlines, had higher income, usually felt stressed or sick, and who preferred eating fruits/vegetables or routinely drank water tended to have a higher rate of consumption of dietary supplements. Participants gave priority over a product with guaranteed quality when they made decision to purchase dietary supplements, but their purchase was also influenced by the attractiveness of the product and advertisement for it.

  9. Geochemical characteristics of the oceanic island- type volcanic rocks in the Chiang Mai zone, northern Thailand

    Institute of Scientific and Technical Information of China (English)

    SHEN Shangyue; FENG Qinglai; ZHANG Zhibin; CHONGPAN Chonglakmani

    2009-01-01

    The oceanic island volcanic rocks in the Chiang Mai zone, northern Thailand, are usually covered by Lower Carboniferous and Upper Permian shallow-water carbonate rocks, with the Hawaii rocks and potash trachybasalt being the main rock types. The alkaline series is dominant with sub-alkaline series occurring in few cases. The geochemical characteristics are described as follows: the major chemical compositions are characterized by high TiO2, high P2O5 and medium K2O; the rare-earth elements are characterized by right-inclined strong LREE-enrichment patterns; the trace element patterns are of the upward-bulging K-Ti enrichment type; multi-component plots falling within the fields of oceanic island basalts and alkali basalts, belonging to the oceanic island-type volcanic rocks, which are similar to the equivalents in Deqin and Gengma (the Changning-Menglian zone) of Yunnan Province, China.

  10. [Anu Mai Kõll. The village and the class war : anti-kulak campaign in Estonia] / Karsten Brüggemann

    Index Scriptorium Estoniae

    Brüggemann, Karsten, 1965-

    2015-01-01

    Arvustus: Kõll, Anu Mai. The village and the class war : anti-kulak campaign in Estonia (Historical studies in Eastern Europe and Eurasia, 2). Central European University Press. Budapest and New York 2013

  11. [Anu Mai Kõll. The village and the class war : anti-kulak campaign in Estonia] / Karsten Brüggemann

    Index Scriptorium Estoniae

    Brüggemann, Karsten, 1965-

    2015-01-01

    Arvustus: Kõll, Anu Mai. The village and the class war : anti-kulak campaign in Estonia (Historical studies in Eastern Europe and Eurasia, 2). Central European University Press. Budapest and New York 2013

  12. Técnica de amostragem para comparar o dano causado pela lagarta-da-espiga, Heliothis zea (Boddie, em cultivares de milho Sampling techniques to compare the damage by Heliothis zea (Boddie in corn varieties

    Directory of Open Access Journals (Sweden)

    Violeta Nagai

    1986-01-01

    detected by the statistical test, and that each treatment mean can be estimated with a standard error of 0.10 y or a standard error of 0.20 y. The data were obtained from two field experiments, carried out in Instituto Agronômico, Campinas, State of São Paulo, Brazil. The treatments were: cultivar Asteca Prolífico VRPE VII, which is resistant to Heliothis zea; Hmd 7974, a susceptible double hybrid; cultivars Maya XVI and HS 7777. A randomized complete block design with ten replicates was used, and each plot consisted of four rows with 50 plants per row. The variance components method was used to define the type of sampling. The most important variance component was due to the variability among units within rows. The following minimum sample sizes can be used to detect the difference between two means: 6 blocks with 4 rows of 24 plants for a difference of 0.10 y and 5 blocks with 3 rows of 6 plants for a difference of 0.20 y. For estimating the mean damage with 0.10 y as the half confidence interval on the mean of the population, the following minimum sample sizes can be used: for cultivar Asteca, 7 blocks with 4 rows of 30 plants per row; for the hybrids Hmd 7974, HS 7777 and cultivar Maya, 5 blocks with 2 rows of 24 plants per row. If a 0.20 y is specified, as the half confidence interval on the mean, it can be used 5 blocks with 3 rows of 12 plants for cultivar Asteca and 5 blocks with 2 rows of 6 plants for the other three cultivars.

  13. O sintoma ou o que o sujeito tem de mais real

    Directory of Open Access Journals (Sweden)

    Marcelo Ricardo Pereira

    2012-03-01

    Full Text Available O sintoma não é um sinal de uma doença, como habitualmente se pensa a partir da ordem médica, mas um fenômeno subjetivo constituído pela realização deformada do desejo. Ele é, diz Freud, uma pantomima do desejo: uma mescla de restrição e gozo. Por isso, há algo do sintoma que não cede à decifração e se mostra aderente à fixação; algo que “retorna a um tipo de autoerotismo difuso”. Lacan encontrou melhores chaves para escrever isso. O sintoma é aquilo que as pessoas têm de mais real; é, diz ele, a própria “natureza da realidade humana”. Nenhuma interpretação o erradica, pois ele é real. O real – sabemos – não pode ser reduzido à realidade concreta, mas é justamente o que a atropela. É a coisa sobre a qual não se tem como dizer ou aquilo que para o sujeito é expulso da realidade pela intervenção da palavra. E aqui, defendemos: essa coisa para o neurótico é a infância; essa que retorna desde seu inconsciente. A infância só existe falada pelo adulto psicanalisado, que quer em vão decifrá-la, fixando-se nela. Ela é o seu ponto real; e, por isso, seu sintoma. O infantil como sintoma: eis o que talvez o sujeito tenha de mais real.

  14. High Resolution Measurement of Rhizosphere Priming Effects and Temporal Variability of CO2 Fluxes under Zea Mays

    Science.gov (United States)

    Splettstößer, T.; Pausch, J.

    2016-12-01

    Plant induced increase of soil organic matter turnover rates contribute to carbon emissions in agricultural land use systems. In order to better understand these rhizosphere priming effects, we conducted an experiment, which enabled us to monitor CO2 fluxes under zea mays plants with high resolution. The experiment was conducted in a climate chamber where the plants were grown in thin, tightly sealed boxes for 40 days and CO2 efflux from soil was measured twice a day. 13C-CO2 was introduced to allow differentiation between plant and soil derived CO2.This enabled us to monitor root respiration and soil organic matter turnover in the early stages of plant growth and to highlight changes in soil CO2 emissions and priming effects between day and night. The measurements were conducted with a PICARRO G2131-I δ13C high-precision isotopic CO2 Analyzer (PICARRO INC.) utilizing an automated valve system governed by a CR1000 data logger (Campbell Scientific). After harvest roots and shoots were analyzed for 13C content. Microbial biomass, root length density and enzymatic activities in soil were measured and linked to soil organic matter turnover rates. In order to visualize the spatial distribution of carbon allocation to the root system a few plants were additionally labeled with 14C and 14C distribution was monitored by 14C imaging of the root systems over 4 days. Based on the 14C distribution a grid was chosen and the soil was sampled from each square of the grid to investigate the impact of carbon allocation hotspots on enzymatic activities and microbial biomass. First initial results show an increase of soil CO2 efflux in the night periods, whereby the contribution of priming is not fully analyzed yet. Additionally, root tips were identified as hotspots of short term carbon allocation via 14C imaging and an in increase in microbial biomass could be measured in this regions. The full results will be shown at AGU 2016.

  15. Variabilitas dan Heritabilitas Berbagai Karakter Tanaman Jagung ( Zea mays L.) Hasil Persilangan Sendiri (Selfing) Pada Generasi F2

    OpenAIRE

    Abdillah

    2011-01-01

    ABDILLAH: Variability and Heritability some character a corn (Zea mays L) result selfing of second generation. Supervised by JENIMAR AND LUTHFI A.M SIREGAR. The objective of the research was to valuate variabilities of several characters affected by the genotype (σ2g), the interraction between genotype and environment (σ2p), studied heritability and also to see the effect resiprocal breeding of F2 with it’s parents of corn (Zea mays L.). The experiment was conduced at exprimental fi...

  16. Sensitivity studies of the common bean (Vigna unguiculata) and maize (Zea mays) to different soil types from the crude oil drilling site at Kutchalli, Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Anoliefo, G.O. [Dept. of Botany, Univ. of Benin, Benin City (Nigeria); Isikhuemhen, O.S. [Dept. of Natural Resources and Environmental Design, NC Agricultural and Technical State Univ., Greensboro, NC (United States); Ohimain, E.I. [Rohi Biotechnologies Ltd., Port Harcourt (Nigeria)

    2006-02-15

    Background, aims and scope. The economic growth that Nigeria has enjoyed as a result of oil revenue has its drawback through exposure of people in the oil producing areas to environmental contamination, due largely to the increase in the movement of oil. Activities associated with oil well drilling on agricultural lands have led to serious economic losses on the communities affected. The local people in most of these communities are peasants who do not know how to react to drilling wastes or polluted fields where they have their crops. A case under study is the Kutchalli oil drilling area. Methods. Waste pit soil from drilling waste dumps in Kutchalli oil drilling area was tested whole and in combinations with 'clean' soil for their abilities to support plant growth and development in common bean (Vigna unguiculata) and maize (Zea mays). Seed germination, plant height, leaf area, biomass accumulation, respiratory activity as well as soil chemical analysis were used to access the ability of waste pit soil to support plant growth and development in the test plants. Results, discussion and conclusions. Waste pit soil completely inhibited the germination of bean and maize seeds. Waste pit soil in combinations with different proportions of Kutchalli soil gave growth (germination, height of plants, number of leaves, leaf area, etc.) values that were inferior to the control soil (Kutchalli) and the independent control soil (Monguno). Seeds planted in the test soil combinations containing waste pit soil showed significantly low respiratory activity. Waste pit soil seems to be toxic to plant growth and development. Drilling mud in combination with native Kutchalli soil significantly enhanced plant growth and development. Recommendations and outlook. The seed germination, growth and development inhibition by waste pit soil suggests its toxicity. We want to suggest the need for strict control and monitoring of waste pit soil in oil drilling sites. (orig.)

  17. A study of the effects of crude oil pollution and oil-degrading bacteria on some biochemical and growth factors of Zea mays

    Directory of Open Access Journals (Sweden)

    Batoul Keramat

    2014-08-01

    Full Text Available Bacteria-Plant systems for bioremediation of oil polluted sites are one of the most effective approaches of biotechnology in the recent years. It is well known that oil pollution induces oxidative stress in plants. In this research, the effects of crude oil pollution on Zea mays and bioremediation by synergism between plant and crude oil degrading bacteria, four different treatments were designed. Some physiological and microbial factors were assayed for determining the effects of oil pollution. The results showed that 1% crude oil in soil shoot, dry weight was reduced and the amount of phenolic compounds increased. With crude oil and Pseudomonas aeruginosa bacterium, shoot dry weight, chlorophyll (a, total chlorophyll and anthocyanins decreased wherase phenolic compounds, malodialdehyde and catalase enzyme activity increased. With 1% crude oil and Acinetobacter calcoaceticus bacterium, significant changes were seen in the parameters of growth. Photosynthetic pigment did not increase whereas anthocyanin, phenolic compounds, malodialdehyde and catalase activity increased. White Crude oil and the presence of both bacteria shoot dry weight and chlorophyll levels decreased and increased levels of anthocyanin and malon-dialdehyde were observed. Addition of oil to the soil, increased the numbers of crude oil degrading bacteria and heterotrophic bacteria but crude oil were removed from soil by biodegradation. By application of bacterial-plant systems in the field, industrial wastes from refinery and biochemical factories could be removed oppropriately.

  18. Role of microbial inoculation and industrial by-product phosphogypsum in growth and nutrient uptake of maize (Zea mays L.) grown in calcareous soil.

    Science.gov (United States)

    Al-Enazy, Abdul-Aziz R; Al-Oud, Saud S; Al-Barakah, Fahad N; Usman, Adel Ra

    2017-08-01

    Alkaline soils with high calcium carbonate and low organic matter are deficient in plant nutrient availability. Use of organic and bio-fertilizers has been suggested to improve their properties. Therefore, a greenhouse experiment was conducted to evaluate the integrative role of phosphogypsum (PG; added at 0.0, 10, 30, and 50 g PG kg(-1) ), cow manure (CM; added at 50 g kg(-1) ) and mixed microbial inoculation (Incl.; Azotobacter chroococcum, and phosphate-solubilizing bacteria Bacillus megaterium var. phosphaticum and Pseudomonas fluorescens) on growth and nutrients (N, P, K, Fe, Mn, Zn and Cu) uptake of maize (Zea mays L.) in calcareous soil. Treatment effects on soil chemical and biological properties and the Cd and Pb availability to maize plants were also investigated. Applying PG decreased soil pH. The soil available P increased when soil was inoculated and/or treated with CM, especially with PG. The total microbial count and dehydrogenase activity were enhanced with PG+CM+Incl. Inoculated soils treated with PG showed significant increases in NPK uptake and maize plant growth. However, the most investigated treatments showed significant decreases in shoot micronutrients. Cd and Pb were not detected in maize shoots. Applying PG with microbial inoculation improved macronutrient uptake and plant growth. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. Atividade de glutationa S-transferase na metabolização de acetochlor, atrazine e oxyfluorfen em milho (Zea mays L., sorgo (Sorghum bicolor L. e trigo (Triticum aestivum L. (Poaceae Glutathione S-transferase activity in acetochlor, atrazine and oxyfluorfen metabolization in maize (Zea mays L., sorghum (Sorghum bicolor L. and wheat (Triticum aestivumL. (Poaceae

    Directory of Open Access Journals (Sweden)

    Ethel Lourenzi Barbosa Novelli

    2002-05-01

    Full Text Available Este experimento foi conduzido para avaliar a seletividade em plantas dos herbicidas acetochlor, atrazine e oxyfluorfen em relação à atividade da glutationa S-transferase (GST em plantas de milho (Zea mays L., sorgo (Sorghum bicolor L. e trigo (Triticum aestivum L. (Poaceae. A atividade da GST foi detectada às 24, 48 e 72 horas após as aplicaç��es dos tratamentos. Os tratamentos do experimento consistiram de aplicação com água (controle, acetochlor (3 L.ha-1, atrazine (4 L.ha-1 e oxyfluorfen (1 L.ha-1. As maiores atividades de GST foram observadas na presença de acetochlor, principalmente às 48 horas após o tratamento. Esses aumentos foram 105, 148 e 118% em relação ao controle para milho, sorgo e trigo, respectivamente. É sugerido que a GST pode ter papel na degradação de acetochlor e pode ser uma das razões para a seletividade desse herbicida para essas culturas.This experiment was conducted to evaluate the acetochlor, atrazine and oxyfluorfen herbicides plant selectivity, in relation to glutathione S-transferase activity (GST in maize (Zea mays L., sorghum (Sorghum bicolor L. and wheat (Triticum aestivum L (Poaceae plants. GST activity was detected 24, 48 and 72 hours after treatment applications. The experiment's treatments consisted of spraying plants with water (control, acetochlor (3 L.ha-1`, atrazine (4 L.ha-1 and oxyfluorfen (1 L.ha-1. The highest GST activities were observed in presence of acetochlor, mainly at 48 hours after treatment. These increments were 105, 148 and 118% when compared to maize, sorghum and wheat control groups, respectively. It is suggested that the GST may have a role in acetochlor degradation and it may be a reason for this herbicide's selectivity in these crops.

  20. Fertilizer use efficiency by maize (Zea mays) and egusi- melon ...

    African Journals Online (AJOL)

    DBOY

    fertilizers by maize and egusi-melon in various ratios of mixtures in an ultisol in Nigeria. The experiment ... Fertilizer use efficiency (FUE) was generally higher in .... two equal splits at 3 and 8 weeks after planting (WAP) coinciding .... Effects of cropping ratios of maize and Egusi-melon on yield and yield components of maize.

  1. Genetic dissection of the maize (Zea mays L.) MAMP response

    Science.gov (United States)

    Microbe-associated molecular patterns (MAMPs) are highly conserved molecules commonly found in microbes which can be recognized by plant pattern recognition receptors (PRRs). Recognition triggers a suite of responses including production of reactive oxygen species (ROS) and nitric oxide (NO) and ex...

  2. Helicoverpa zea (Lepidoptera: Noctuidae) and Spodoptera frugiperda (Lepidoptera: Noctuidae) Responses to Sorghum bicolor (Poales: Poaceae) Tissues From Lowered Lignin Lines.

    Science.gov (United States)

    Dowd, Patrick F; Sattler, Scott E

    2015-01-01

    The presence of lignin within biomass impedes the production of liquid fuels. Plants with altered lignin content and composition are more amenable to lignocellulosic conversion to ethanol and other biofuels but may be more susceptible to insect damage where lignin is an important resistance factor. However, reduced lignin lines of switchgrasses still retained insect resistance in prior studies. Therefore, we hypothesized that sorghum lines with lowered lignin content will also retain insect resistance. Sorghum excised leaves and stalk pith Sorghum bicolor (L.) Moench (Poales: Poaceae) from near isogenic brown midrib (bmr) 6 and 12 mutants lines, which have lowered lignin content and increased lignocellulosic ethanol conversion efficiency, were examined for insect resistance relative to wild-type (normal BTx623). Greenhouse and growth chamber grown plant tissues were fed to first-instar larvae of corn earworms, Helicoverpa zea (Boddie) and fall armyworms Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), two sorghum major pests. Younger bmr leaves had significantly greater feeding damage in some assays than wild-type leaves, but older bmr6 leaves generally had significantly less damage than wild-type leaves. Caterpillars feeding on the bmr6 leaves often weighed significantly less than those feeding on wild-type leaves, especially in the S. frugiperda assays. Larvae fed the pith from bmr stalks had significantly higher mortality compared with those larvae fed on wild-type pith, which suggested that bmr pith was more toxic. Thus, reducing lignin content or changing subunit composition of bioenergy grasses does not necessarily increase their susceptibility to insects and may result in increased resistance, which would contribute to sustainable production.

  3. Helicoverpa zea (Lepidoptera: Noctuidae) and Spodoptera frugiperda (Lepidoptera: Noctuidae) Responses to Sorghum bicolor (Poales: Poaceae) Tissues From Lowered Lignin Lines

    Science.gov (United States)

    Dowd, Patrick F.; Sattler, Scott E.

    2015-01-01

    The presence of lignin within biomass impedes the production of liquid fuels. Plants with altered lignin content and composition are more amenable to lignocellulosic conversion to ethanol and other biofuels but may be more susceptible to insect damage where lignin is an important resistance factor. However, reduced lignin lines of switchgrasses still retained insect resistance in prior studies. Therefore, we hypothesized that sorghum lines with lowered lignin content will also retain insect resistance. Sorghum excised leaves and stalk pith Sorghum bicolor (L.) Moench (Poales: Poaceae) from near isogenic brown midrib (bmr) 6 and 12 mutants lines, which have lowered lignin content and increased lignocellulosic ethanol conversion efficiency, were examined for insect resistance relative to wild-type (normal BTx623). Greenhouse and growth chamber grown plant tissues were fed to first-instar larvae of corn earworms, Helicoverpa zea (Boddie) and fall armyworms Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), two sorghum major pests. Younger bmr leaves had significantly greater feeding damage in some assays than wild-type leaves, but older bmr6 leaves generally had significantly less damage than wild-type leaves. Caterpillars feeding on the bmr6 leaves often weighed significantly less than those feeding on wild-type leaves, especially in the S. frugiperda assays. Larvae fed the pith from bmr stalks had significantly higher mortality compared with those larvae fed on wild-type pith, which suggested that bmr pith was more toxic. Thus, reducing lignin content or changing subunit composition of bioenergy grasses does not necessarily increase their susceptibility to insects and may result in increased resistance, which would contribute to sustainable production. PMID:25601946

  4. Yields and Yield Components of Maize (Zea Mays L. and Soybean (Glycine Max as Affected by Different Tillage Methods

    Directory of Open Access Journals (Sweden)

    Kvaternjak Ivka

    2015-12-01

    Full Text Available At the experiment station of the Krizevci College of Agriculture, yield and yield components of maize (Zea mays L. and soybean (Glycine max grown in rotation under five different methods of tillage were investigated. The aim of this study was to determine the effect of different tillage methods on yield and yield components of maize and soybean. The results and the determined number of plants per hectare of maize and soybean show that more favorable conditions for germination are in variants where ploughing performed in the autumn (variants C, D and E. During a four-year study, the minimum number of plants per hectare of maize and soybean was found in variant A. The dry season in panicle stage of maize in 2006 has lowered yields compared to 2008, and the drought in 2007 during the seed-filling period reduced the yield and the 1000 kernel weight of soybean compared with 2009 in all variants of tillage methods. The highest grain yield of maize was recorded in variant B. During 2006, with the unfavorable weather conditions, the lowest grain yield of maize was recorded in variant E with intensive tillage treatment. The highest yield of soybean was recorded in variant E, but there were no statistically significant differences compared to variants with the reduction of additional tillage interventions (variant B, C and D. With respect to maize grain and soybean seed yield, variant A was the lowest. Considering the achieved yields of maize grain, there is a possibility of reducing additional tillage interventions, whilst for achieving higher yield of soybean seed intensive tillage is recommended.

  5. Risk assessment for Helicoverpa zea (Lepidoptera: Noctuidae) resistance on dual-gene versus single-gene corn.

    Science.gov (United States)

    Edwards, Kristine T; Caprio, Michael A; Allen, K Clint; Musser, Fred R

    2013-02-01

    Recent Environmental Protection Agency (EPA) decisions regarding resistance management in Bt-cropping systems have prompted concern in some experts that dual-gene Bt-corn (CrylA.105 and Cry2Ab2 toxins) may result in more rapid selection for resistance in Helicoverpa zea (Boddie) than single-gene Bacillus thuringiensis (Bt)-corn (CrylAb toxin). The concern is that Bt-toxin longevity could be significantly reduced with recent adoption of a natural refuge for dual-gene Bt-cotton (CrylAc and Cry2Ab2 toxins) and concurrent reduction in dual-gene corn refuge from 50 to 20%. A population genetics framework that simulates complex landscapes was applied to risk assessment. Expert opinions on effectiveness of several transgenic corn and cotton varieties were captured and used to assign probabilities to different scenarios in the assessment. At least 350 replicate simulations with randomly drawn parameters were completed for each of four risk assessments. Resistance evolved within 30 yr in 22.5% of simulations with single-gene corn and cotton with no volunteer corn. When volunteer corn was added to this assessment, risk of resistance evolving within 30 yr declined to 13.8%. When dual-gene Bt-cotton planted with a natural refuge and single-gene corn planted with a 50% structured refuge was simulated, simultaneous resistance to both toxins never occurred within 30 yr, but in 38.5% of simulations, resistance evolved to toxin present in single-gene Bt-corn (CrylAb). When both corn and cotton were simulated as dual-gene products, cotton with a natural refuge and corn with a 20% refuge, 3% of simulations evolved resistance to both toxins simultaneously within 30 yr, while 10.4% of simulations evolved resistance to CrylAb/c toxin.

  6. Pre-treatment of seeds with static magnetic field ameliorates soil water stress in seedlings of maize (Zea mays L.).

    Science.gov (United States)

    Anand, Anjali; Nagarajan, Shantha; Verma, A P S; Joshi, D K; Pathak, P C; Bhardwaj, Jyotsna

    2012-02-01

    The effect of magnetic field (MF) treatments of maize (Zea mays L.) var. Ganga Safed 2 seeds on the growth, leaf water status, photosynthesis and antioxidant enzyme system under soil water stress was investigated under greenhouse conditions. The seeds were exposed to static MFs of 100 and 200 mT for 2 and 1 h, respectively. The treated seeds were sown in sand beds for seven days and transplanted in pots that were maintained at -0.03, -0.2 and -0.4 MPa soil water potentials under greenhouse conditions. MF exposure of seeds significantly enhanced all growth parameters, compared to the control seedlings. The significant increase in root parameters in seedlings from magnetically-exposed seeds resulted in maintenance of better leaf water status in terms of increase in leaf water potential, turgor potential and relative water content. Photosynthesis, stomatal conductance and chlorophyll content increased in plants from treated seeds, compared to control under irrigated and mild stress condition. Leaves from plants of magnetically-treated seeds showed decreased levels of hydrogen peroxide and antioxidant defense system enzymes (peroxidases, catalase and superoxide dismutase) under moisture stress conditions, when compared with untreated controls. Mild stress of -0.2 MPa induced a stimulating effect on functional root parameters, especially in 200 mT treated seedlings which can be exploited profitably for rain fed conditions. Our results suggested that MF treatment (100 mT for 2 h and 200 for 1 h) of maize seeds enhanced the seedling growth, leaf water status, photosynthesis rate and lowered the antioxidant defense system of seedlings under soil water stress. Thus, pre sowing static magnetic field treatment of seeds can be effectively used for improving growth under water stress.

  7. Cadmium toxicity in Maize (Zea mays L.): consequences on antioxidative systems, reactive oxygen species and cadmium accumulation.

    Science.gov (United States)

    Anjum, Shakeel Ahmad; Tanveer, Mohsin; Hussain, Saddam; Bao, Mingchen; Wang, Longchang; Khan, Imran; Ullah, Ehsan; Tung, Shahbaz Atta; Samad, Rana Abdul; Shahzad, Babar

    2015-11-01

    Increased cadmium (Cd) accumulation in soils has led to tremendous environmental problems, with pronounced effects on agricultural productivity. Present study investigated the effects of Cd stress imposed at various concentrations (0, 75, 150, 225, 300, 375 μM) on antioxidant activities, reactive oxygen species (ROS), Cd accumulation, and productivity of two maize (Zea mays L.) cultivars viz., Run Nong 35 and Wan Dan 13. Considerable variations in Cd accumulation and in behavior of antioxidants and ROS were observed under Cd stress in both maize cultivars, and such variations governed by Cd were concentration dependent. Exposure of plant to Cd stress considerably increased Cd concentration in all plant parts particularly in roots. Wan Dan 13 accumulated relatively higher Cd in root, stem, and leaves than Run Nong 35; however, in seeds, Run Nong 35 recorded higher Cd accumulation. All the Cd toxicity levels starting from 75 μM enhanced H2O2 and MDA concentrations and triggered electrolyte leakage in leaves of both cultivars, and such an increment was more in Run Nong 35. The ROS were scavenged by the enhanced activities of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, and glutathione peroxidase in response to Cd stress, and these antioxidant activities were higher in Wan Dan 13 compared with Run Nong 35 at all Cd toxicity levels. The grain yield of maize was considerably reduced particularly for Run Nong 35 under different Cd toxicity levels as compared with control. The Wan Dan 13 was better able to alleviate Cd-induced oxidative damage which was attributed to more Cd accumulation in roots and higher antioxidant activities in this cultivar, suggesting that manipulation of these antioxidants and enhancing Cd accumulation in roots may lead to improvement in Cd stress tolerance.

  8. Identification and Validation of miRNAs Associated with the Resistance of Maize (Zea mays L.) to Exserohilum turcicum

    Science.gov (United States)

    Jin, Weibo

    2014-01-01

    Northern leaf blight, caused by the fungus Exserohilum turcicum (Pass.), is a major disease of maize (Zea mays L.). MicroRNAs (miRNAs) have been recently reported as gene expression regulators related to several stress responses; however, evidence of the role of miRNAs in plant response to biotic stresses is limited. In this study, the miRNA expression patterns in maize in response to E. turcicum stress were investigated using a plant miRNA microarray platform. A total of 118 miRNAs were detected in mock- and E. turcicum-inoculated leaves. Among these miRNAs, miR530, miR811, miR829, and miR845 were identified as new miRNAs in maize through a homology-based approach. The secondary structures and putative targets of these miRNAs were also predicted. In addition, four miRNAs were differentially regulated in response to E. turcicum: miR811, miR829, miR845, and miR408. The functional annotation of the predicted targets indicated that these stress-responsive miRNAs regulate metabolic, morphologic, and physiologic adaptations in maize seedlings at the post-transcriptional level. Four targets were negatively correlated with their corresponding miRNAs (miR811, miR829, and miR408). Furthermore, we have demonstrated for the first time that miR811 and miR829 confers a high degree of resistance to E. turcicum, which can be used in maize breeding programs. PMID:24489881

  9. Genome-wide identification, splicing, and expression analysis of the myosin gene family in maize (Zea mays).

    Science.gov (United States)

    Wang, Guifeng; Zhong, Mingyu; Wang, Jiajia; Zhang, Jushan; Tang, Yuanping; Wang, Gang; Song, Rentao

    2014-03-01

    The actin-based myosin system is essential for the organization and dynamics of the endomembrane system and transport network in plant cells. Plants harbour two unique myosin groups, class VIII and class XI, and the latter is structurally and functionally analogous to the animal and fungal class V myosin. Little is known about myosins in grass, even though grass includes several agronomically important cereal crops. Here, we identified 14 myosin genes from the genome of maize (Zea mays). The relatively larger sizes of maize myosin genes are due to their much longer introns, which are abundant in transposable elements. Phylogenetic analysis indicated that maize myosin genes could be classified into class VIII and class XI, with three and 11 members, respectively. Apart from subgroup XI-F, the remaining subgroups were duplicated at least in one analysed lineage, and the duplication events occurred more extensively in Arabidopsis than in maize. Only two pairs of maize myosins were generated from segmental duplication. Expression analysis revealed that most maize myosin genes were expressed universally, whereas a few members (XI-1, -6, and -11) showed an anther-specific pattern, and many underwent extensive alternative splicing. We also found a short transcript at the O1 locus, which conceptually encoded a headless myosin that most likely functions at the transcriptional level rather than via a dominant-negative mechanism at the translational level. Together, these data provide significant insights into the evolutionary and functional characterization of maize myosin genes that could transfer to the identification and application of homologous myosins of other grasses.

  10. Optimization of drying process of Zea Mays malt to use as alternative source of amylolytics enzymes

    Directory of Open Access Journals (Sweden)

    Joana Paula Menezes Biazus

    2005-06-01

    Full Text Available This work aimed to study the drying process optimization of maize (Zea Mays malt for obtaining maize malt, without affecting enzymatic activity of alpha e beta-amylases from maize malt. Results showed that dryer operation must occur in zone at 54°C and 5.18-6 h process time. The maize malt obtained had good enzymatic properties.Este trabalho objetivou a otimização da secagem do malte de milho (Zea Mays para obter um malte sem afetar a atividade das enzimas presentes neste, alfa e beta -amilases. Os resultados mostraram que a operação do secador deve ser feita a 54°C e entre 5,18-6 h de processo. O malte obtido possuiu boas propriedades enzimáticas.

  11. Influence of microgravity on cellular differentiation in root caps of Zea mays

    Science.gov (United States)

    Moore, R.; Fondren, W. M.; McClelen, C. E.; Wang, C. L.

    1987-01-01

    We launched imbibed seeds of Zea mays into outer space aboard the space shuttle Columbia to determine the influence of microgravity on cellular differentiation in root caps. The influence of microgravity varied with different stages of cellular differentiation. Overall, microgravity tended to 1) increase relative volumes of hyaloplasm and lipid bodies, 2) decrease the relative volumes of plastids, mitochondria, dictyosomes, and the vacuome, and 3) exert no influence on the relative volume of nuclei in cells comprising the root cap. The reduced allocation of dictyosomal volume in peripheral cells of flight-grown seedlings correlated positively with their secretion of significantly less mucilage than peripheral cells of Earth-grown seedlings. These results indicate that 1) microgravity alters the patterns of cellular differentiation and structures of all cell types comprising the root cap, and 2) the influence of microgravity on cellular differentiation in root caps of Zea mays is organelle specific.

  12. Inducing gravitropic curvature of primary roots of Zea mays cv Ageotropic

    Science.gov (United States)

    Moore, R.; Evans, M. L.; Fondren, W. M.

    1990-01-01

    Primary roots of the mutant 'Ageotropic' cultivar of Zea mays are nonresponsive to gravity. Their root caps secrete little or no mucilage and touch the root only at the extreme apex. A gap separates the cap and root at the periphery of the cap. Applying mucilage from normal roots or substances with a consistency similar to that of mucilage to tips of mutant roots causes these roots to become strongly graviresponsive. Gravicurvature stops when these substances are removed. Caps of some mutants secrete small amounts of mucilage and are graviresponsive. These results indicate that (a) the lack of graviresponsiveness in the mutant results from disrupting the transport pathway between the cap and root, (b) movement of the growth-modifying signal from the cap to the root occurs via an apoplastic pathway, and (c) mucilage is necessary for normal communication between the root cap and root in Zea mays cv Ageotropic.

  13. Una filosofía para América Latina: Leopoldo Zea

    Directory of Open Access Journals (Sweden)

    Giuseppe Cacciatore

    2004-01-01

    Full Text Available Uno de los mas significativos recorrido filosoficos e hsitorico-culturales a traves de los que se ha manisfestado la reflexion sobre la identidad latinoamericana es indudablemente el trazado por el pensador mexicano Leopoldo Zea, alumno predilecto de jose gaos. En el, como en tanto otros intelectuales de los paises latinos del conteniente americano el problema de la individuacion de las trazas de una autonoma dimension filosofica (y de su ambivalente relacion con la tradicion indigena pre-colonial y con los modelos de la cultura europea se liga constante y significativamente al evento traumatico y dramatico de la conquista y del genocidio. Zea no se cierra en esta dicatomia civilizacion precolombina/civilizacion europea, ni olvida la que quizas es la verdadera especificidad del continente americano centromeridional, la multiculturalidad y la multietnia, el denominado mestizaje.

  14. La historia de las ideas en la perspectiva de Leopoldo Zea.

    Directory of Open Access Journals (Sweden)

    Susana Vázquez

    2015-09-01

    Full Text Available Leopoldo Zea (México 1912 para muchos el mayor pensador de Hispanoamérica en la segunda mitad del siglo XX, ejerce un indudable magisterio en elplano de la historia de las idas a nivel continental (...Contenido: Introducción. Contexto histórico y genealogía de sus conceptos fundamentales. Análisis de algunas de sus obras. Reflexión final

  15. Antihypertensive and antioxidant activity of atomized andean purple corn (Zea mayz L) hydroalcoholic extract in rats

    OpenAIRE

    Arroyo, Jorge; Facultad de Medicina, Universidad Nacional Mayor de San Marcos. Lima, Perú. Químico farmaceútico.; Raez, Ernesto; Facultad de Medicina, Universidad Nacional Mayor de San Marcos. Lima, Perú. Médico patólogo.; Rodríguez, Miguel; Facultad de Odontología, Universidad Nacional Mayor de San Marcos. Lima, Perú. Odontólogo.; Chumpitaz, Víctor; Facultad Odontología, Universidad Nacional Mayor de San Marcos. Lima, Perú. Odontólogo.; Burga, Jonny; Facultad de Odontología, Universidad Nacional Mayor de San Marcos. Lima, Perú. Odontólogo.; De la Cruz, Walter; Facultad de Farmacia y Bioquímica, Universidad Nacional Mayor de San Marcos. Lima, Perú. Médico.; Valencia, José; Facultad de Farmacia y Bioquímica, Universidad Nacional Mayor de San Marcos. Lima, Perú. Químico Farmacéutico.

    2008-01-01

    Objectives. To determine the antihypertensive and antioxidant activity of the atomized hydroalcoholic extract of Zea mays L. (Andean purple corn) in rats with induced hypertension. Material and methods. We used five groups of six Holtzmann rats each, one without hypertension (negative control) and four with hypertension induced by L-NAME: positive control and three groups for the doses of 250, 500 and 1000 mg/kg, respectively. The treatment was carried out orally once a day for 25 days. Th...

  16. La historia de las ideas en la perspectiva de Leopoldo Zea.

    OpenAIRE

    Susana Vázquez

    2015-01-01

    Leopoldo Zea (México 1912) para muchos el mayor pensador de Hispanoamérica en la segunda mitad del siglo XX, ejerce un indudable magisterio en elplano de la historia de las idas a nivel continental (...)Contenido: Introducción. Contexto histórico y genealogía de sus conceptos fundamentales. Análisis de algunas de sus obras. Reflexión final

  17. PENYELENGGARAAN MAKANAN DAN TINGKAT KEPUASAN KONSUMEN DI KANTIN ZEA MAYS INSTITUT PERTANIAN BOGOR

    Directory of Open Access Journals (Sweden)

    Arnati Wulansari

    2013-11-01

    Full Text Available ABSTRACTThis research aimed was to know food service and level of customer satisfaction in the Zea Mays cafetaria at Bogor Agricultural University. Case study and descriptive analysis were applied in this study. Sampling method of purposive sampling was carried out and number of subjects used was 95 people. The food service in the Zea Mays cafetaria consists of planning, purchasing, receiving, storing, processing, and distributing. The result of analysis based on Importance Performance Analysis showed that the most important attribute was the security and hygiene product and the highest performance levels was the cleanliness of dining room. More than fifty percent subjects was concerned against nutrient content of the menu (50.5%. Based on the Customer Satisfaction Index the satisfaction value was 69.3 (satisfied. There was a correlation between job and education level with quality of the product and between income with nutrient content (p<0.05.Keywords: customer, food service, satisfactionABSTRAKPenelitian ini bertujuan untuk mengetahui penyelenggaraan makanan dan tingkat kepuasan konsumen di Kantin Zea Mays Institut Pertanian Bogor. Penelitian ini menggunakan metode penelitian analisis deskriptif dan studi kasus. Metode penarikan subjek dilakukan secara purposive dan sebanyak 95 subjek digunakan dalam penelitian ini. Penyelenggaraan makanan di Kantin Zea Mays terdiri dari perencanaan, pembelian, penerimaan, penyimpanan, pengolahan, dan penyajian. Berdasarkan hasil analisis Importance Performance Analysis (IPA diketahui bahwa atribut yang dirasakan paling penting adalah keamanan dan kebersihan produk sedangkan atribut tingkat kinerja yang paling tinggi skornya adalah kebersihan tempat makan. Lebih dari separuh subjek masih memerhatikan kandungan gizi menu (50.5%. Berdasarkan Customer Satisfaction Index (CSI diperoleh nilai kepuasan sebesar 69.3 (puas. Terdapat hubungan antara pekerjaan dan tingkat pendidikan dengan penilaian atribut mutu produk

  18. Abscisic acid is not necessary for gravitropism in primary roots of Zea mays

    Science.gov (United States)

    Moore, R.

    1990-01-01

    Primary roots of Zea mays L. cv. Tx 5855 treated with fluridone are strongly graviresponsive, but have undetectable levels of abscisic acid (ABA). Primary roots of the carotenoid-deficient w-3, vp-5, and vp-7 mutants of Z. mays are also graviresponsive despite having undetectable amounts of ABA. Graviresponsive roots of untreated and wild-type seedlings contain 286 to 317 ng ABA g-1 f. wt, respectively. These results indicate that ABA is not necessary for root gravicurvature.

  19. Movement of endogenous calcium in the elongating zone of graviresponding roots of Zea mays

    Science.gov (United States)

    Moore, R.; Cameron, I. L.; Smith, N. K.

    1989-01-01

    Endogenous calcium (Ca) accumulates along the lower side of the elongating zone of horizontally oriented roots of Zea mays cv. Yellow Dent. This accumulation of Ca correlates positively with the onset of gravicurvature, and occurs in the cytoplasm, cell walls and mucilage of epidermal cells. Corresponding changes in endogenous Ca do not occur in cortical cells of the elongating zone of intact roots. These results indicate that the calcium asymmetries associated with root gravicurvature occur in the outermost layers of the root.

  20. Eco-toxicity of Land Application of Sewage Sludge on Zea Mays%污泥施用土壤对玉米的生态毒性效应

    Institute of Scientific and Technical Information of China (English)

    戴亮; 任珺; 张军平; 李华

    2011-01-01

    The eco-toxicological effects of sewage sludge application on seed germination, root elongation test,biomass,chlorophyll content, proline content and heavy metals content in Zea mays were studied by pot experiments. The results showed that the content of Pb,Cu,Zn in the soil did not exceed the national standard of Environmental Quality Standards for Soils for Grade Ⅱ(GB-1518-1995). The biomass of Zea mays was increased significantly and was better than the controlled one after land application of sewage sludge. Zea mays seedling emergence and root length were inhibited in varying degrees due to sewage sludge application,showing the effects of dose-effect relationship with the increased amount of sludge. Zea mays root length was restrained by heavy metals in the soil,and the effects of heavy metals in the soil on plant root system should be considered with land application of sewage sludge. The total chlorophyll content of Zea mays with the amount of sludge application showed a rapid decrease after a increase. The proline content of Zea mays leaves compared with the controlled one showed a big increase after sewage sludge application, which grew nearly eight times, but threshold did not appear. In conclusion, Zea mays on the sludge applied showed a strong adaptability and tolerance in the ratio of sludge in the mixed soil of dry weight lower than 25%.%采用盆栽试验方法,研究污泥土地利用后对玉米种子出苗、单株生物量、根伸长、叶片内叶绿素含量和脯氨酸含量及体内重金属含量等指标的生态毒理学效应.结果表明:污泥施用后,玉米生物量显著高于对照,但出苗率和根长受到不同程度的抑制.土壤中的重金属对玉米根长有明显的抑制作用,在施污泥肥时应该重点考虑土壤中重金属对植物根系的影响.玉米叶绿素总含量随着污泥施加量呈先升后降的趋势.玉米叶片的脯氨酸含量与对照相比有大幅的上升,但并未出现阀值.玉米根

  1. Questões mais freqüentes na área de astronomia

    Science.gov (United States)

    Segundo, H. A. S.; Garcia, G. C.; Caretta, C. A.; Lima, F. P.

    2003-08-01

    É amplamente reconhecido que as pessoas em geral têm grande fascínio e interesse pela Astronomia. Por outro lado, o conteúdo dessa área incluído no ensino formal está longe de ser abrangente e suficiente para suprir a demanda. Esse interesse permite otimizar a divulgação e o ensino não formal de Astronomia aliando a adequação do conteúdo à expectativa das pessoas. Nesse intuito, nosso trabalho busca mapear que assuntos da Astronomia despertam mais a atenção e o interesse das pessoas e o quanto disso é estimulado pela mídia, que freqüentemente aproveita-se desse interesse de forma sensacionalista, trazendo contribuições positivas e negativas. Para esta avaliação, utilizamos as pesquisas específicas e de caracterização do público que freqüentou o MAst nos anos de 2001 a 2003, pesquisa das matérias de Astronomia veiculadas na mídia escrita da cidade do Rio de Janeiro no mesmo período, além da base de dados do programa Pergunte a um astrônomo, realizado no Observatório Nacional nos anos de 1997 a 1999. Para a análise dos dados, dividimos as perguntas em dez categorias, cada uma com suas subcategorias, tomando como referência as divisões, comissões e grupos de trabalho da IAU. Apresentamos neste trabalho os resultados dessa pesquisa, que incluem, entre outros, a predominância de questões nas categorias Observação do Céu e Sistemas Planetários enquanto nos jornais dominam as notícias de Sistemas Planetários e Espaço & Astronáutica. Outro resultado interessante indicou que as dúvidas de crianças do ensino fundamental se concentram em algumas categorias enquanto as questões de adultos são mais distribuídas por todas as categorias. Os resultados dessa pesquisa serão aplicados diretamente no aperfeiçoamento das atividades do Programa de Observação de Céu, bem como na elaboração de novos projetos e eventos realizados no MAst.

  2. Positional cloning in maize (Zea mays subsp. mays, Poaceae)1

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    Gallavotti, Andrea; Whipple, Clinton J.

    2015-01-01

    • Premise of the study: Positional (or map-based) cloning is a common approach to identify the molecular lesions causing mutant phenotypes. Despite its large and complex genome, positional cloning has been recently shown to be feasible in maize, opening up a diverse collection of mutants to molecular characterization. • Methods and Results: Here we outline a general protocol for positional cloning in maize. While the general strategy is similar to that used in other plant species, we focus on the unique resources and approaches that should be considered when applied to maize mutants. • Conclusions: Positional cloning approaches are appropriate for maize mutants and quantitative traits, opening up to molecular characterization the large array of genetic diversity in this agronomically important species. The cloning approach described should be broadly applicable to other species as more plant genomes become available. PMID:25606355

  3. Antiplasmodial activity and cytotoxicity of ethanol extract of Zea mays root

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    Jude Efiom Okokon

    2017-04-01

    Full Text Available Objective:Zea mays root decoction that has been traditionally used for the treatment of malaria by various tribes in Nigeria, was evaluated for antimalarial potential against malaria parasites using in vivo and in vitro models. Materials and Methods: The root extract of Zea mays was investigated for antimalarial activity against Plasmodium berghei in mice using rodent malaria models; suppressive, prophylactic and curative tests and in vitro antiplasmodial activity against chloroquine-sensitive (Pf 3D7 and resistant (Pf INDO strains of Plasmodium falciparum using SYBR green assay method. Median lethal dose and cytotoxic activity against HeLa and HEKS cells were assessed and phytochemical screening was also carried out using standard procedures. Results: The LD50 value of root extract was found to be 474.34 mg/kg. The crude extract (45-135 mg/kg, p.o showed significant (p100 μg/ml against both HeLa and HEKS cell lines. Conclusion: These results suggest that the root extract of Zea mays possesses antimalarial activity against both chloroquine-sensitive and resistant malaria and these data justify its use in ethnomedicine to treat malaria infections.

  4. The Impact of Inter-Kernel Movement in the Evolution of Resistance to Dual-Toxin Bt-Corn Varieties in Helicoverpa zea (Lepidoptera: Noctuidae).

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    Caprio, Michael A; Martinez, Jeannette C; Porter, Patrick A; Bynum, Ed

    2016-02-01

    Seeds or kernels on hybrid plants are primarily F(2) tissue and will segregate for heterozygous alleles present in the parental F(1) hybrids. In the case of plants expressing Bt-toxins, the F(2) tissue in the kernels will express toxins as they would segregate in any F(2) tissue. In the case of plants expressing two unlinked toxins, the kernels on a Bt plant fertilized by another Bt plant would express anywhere from 0 to 2 toxins. Larvae of corn earworm [Helicoverpa zea (Boddie)] feed on a number of kernels during development and would therefore be exposed to local habitats (kernels) that varied in their toxin expression. Three models were developed for plants expressing two Bt-toxins, one where the traits are unlinked, a second where the traits were linked and a third model assuming that maternal traits were expressed in all kernels as well as paternally inherited traits. Results suggest that increasing larval movement rates off of expressing kernels tended to increase durability while increasing movement rates off of nonexpressing kernels always decreased durability. An ideal block refuge (no pollen flow between blocks and refuges) was more durable than a seed blend because the refuge expressed no toxins, while pollen contamination from plants expressing toxins in a seed blend reduced durability. A linked-trait model in an ideal refuge model predicted the longest durability. The results suggest that using a seed-blend strategy for a kernel feeding insect on a hybrid crop could dramatically reduce durability through the loss of refuge due to extensive cross-pollination.

  5. Plant dependence on rhizobia for nitrogen influences induced plant defenses and herbivore performance.

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    Dean, Jennifer M; Mescher, Mark C; De Moraes, Consuelo M

    2014-01-21

    Symbiotic rhizobia induce many changes in legumes that could affect aboveground interactions with herbivores. We explored how changing the intensity of Bradyrhizobium japonicum, as modulated by soil nitrogen (N) levels, influenced the interaction between soybean (Glycine max) and herbivores of different feeding guilds. When we employed a range of fertilizer applications to manipulate soil N, plants primarily dependent on rhizobia for N exhibited increased root nodulation and higher levels of foliar ureides than plants given N fertilizer; yet all treatments maintained similar total N levels. Soybean podworm (Helicoverpa zea) larvae grew best on plants with the highest levels of rhizobia but, somewhat surprisingly, preferred to feed on high-N-fertilized plants when given a choice. Induction of the defense signaling compound jasmonic acid (JA) by H. zea feeding damage was highest in plants primarily dependent on rhizobia. Differences in rhizobial dependency on soybean did not appear to affect interactions with the phloem-feeding soybean aphid (Aphis glycines). Overall, our results suggest that rhizobia association can affect plant nutritional quality and the induction of defense signaling pathways and that these effects may influence herbivore feeding preferences and performance-though such effects may vary considerably for different classes of herbivores.

  6. Molecular identification of larval trematode in intermediate hosts from Chiang Mai, Thailand.

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    Chuboon, Suksan; Wongsawad, Chalobol

    2009-11-01

    Snail and fish intermediate hosts were collected from rice fields in 3 districts; Mueang, Mae Taeng and Mae Rim of Chiang Mai Province during April-July 2008. For identification of larval trematode infection, standard (cracked for snail and enzymatically digested for fish) and molecular methods were performed. The results showed that three types of cercariae were found, pleurolophocercus, cotylocercous, and echinostome among 4 species of snail with a prevalence of 29, 23 and 3% respectively. Melanoides tuberculata snail was the most susceptible host for cercariae infection. Four species of metacercariae, Haplorchis taichui, Stellantchasmus falcatus, Haplorchoides sp and Centrocestus caninus, were found with a prevalence of 67, 25, 60 and 20%, respectively. The Siamese mud carp (Henicorhynchus siamensis) was the most susceptible fish host for H. taichui, and half- beaked fish (Dermogenys pusillus) for S. falcatus metacercariae infection, whereas Haplorchoides sp and C. caninus were concomitantly found in Puntius brevis. HAT-RAPD profile confirmed that pleurolophocercus cercariae found in Melanoides tuberculata from Mae Taeng District belonged to H. taichui and in Tarebia granifera from Mueang District were S. falcatus.

  7. Soil-Gas Radon Anomaly Map of an Unknown Fault Zone Area, Chiang Mai, Northern Thailand

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    Udphuay, S.; Kaweewong, C.; Imurai, W.; Pondthai, P.

    2015-12-01

    Soil-gas radon concentration anomaly map was constructed to help detect an unknown subsurface fault location in San Sai District, Chiang Mai Province, Northern Thailand where a 5.1-magnitude earthquake took place in December 2006. It was suspected that this earthquake may have been associated with an unrecognized active fault in the area. In this study, soil-gas samples were collected from eighty-four measuring stations covering an area of approximately 50 km2. Radon in soil-gas samples was quantified using Scintrex Radon Detector, RDA-200. The samplings were conducted twice: during December 2014-January 2015 and March 2015-April 2015. The soil-gas radon map obtained from this study reveals linear NNW-SSE trend of high concentration. This anomaly corresponds to the direction of the prospective fault system interpreted from satellite images. The findings from this study support the existence of this unknown fault system. However a more detailed investigation should be conducted in order to confirm its geometry, orientation and lateral extent.

  8. Mais Médicos: um programa brasileiro em uma perspectiva internacional

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    Felipe Proenço de Oliveira

    2015-09-01

    Full Text Available A escassez de profissionais de saúde em áreas remotas e vulneráveis é um importante obstáculo para a universalização do acesso à saúde em diversos países. Este artigo examina as políticas de provimento de profissionais de saúde na Austrália, nos Estados Unidos da América e no Brasil. Apesar do sucesso parcial de iniciativas anteriores, foi apenas com o Programa Mais Médicos que a provisão de médicos em áreas vulneráveis teve a magnitude e a resposta em tempo adequado para atender a demanda dos municípios brasileiros. Estão em curso, no país, mudanças quantitativas e qualitativas na formação médica, que buscam garantir não apenas a universalidade, mas, também, a integralidade e sustentabilidade do Sistema Único de Saúde. O êxito dessas iniciativas dependerão da continuidade da articulação interfederativa, de políticas regulatórias de estado, bem como, do constante monitoramento e aprimoramento do programa.

  9. Current State Overview of the Vama Veche - 2 Mai Marine Reserve, Black Sea, Romania

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    Victor Niţă

    2012-03-01

    Full Text Available The Vama Veche - 2 Mai marine area is an almost unique combination at the Romanian coast, covering a wide variety of elementaryhabitats, the area being considered a true mosaic. The extremely rich benthic and pelagic life, expressed by the high biodiversity in the area, isa real milestone for the Romanian coast, being at the same time shelter and breeding area for many nektonic marine organisms. The NationalInstitute for Marine Research and Development “Grigore Antipa“ Constanta was custodian of the reserve in the period 2004 - 2009, duringwhich an intense research activity was developed in the area, evidenced by the numerous scientific papers published, as well as the ManagementPlan and Regulation of the Reserve, completed and submitted for approval to the Ministry of Environment. Since December 2011, the Institutehas again taken into custody the Vama Veche Reserve, for a period of five years. The paper herein is a brief scan of the current state of the protectedarea, based mainly on the research conducted there by the Institute, within many projects focusing on the quality of the Romanian marineenvironment.

  10. Molecular Phylogenetics of Centrocestus formosanus (Digenea: Heterophyidae) Originated from Freshwater Fish from Chiang Mai Province, Thailand

    Science.gov (United States)

    Wongsawad, Chalobol; Wongsawad, Pheravut; Sukontason, Kom; Maneepitaksanti, Worawit; Nantarat, Nattawadee

    2017-01-01

    This study aimed to investigate the morphology and reconstruct the phylogenetic relationships of Centrocestus formosanus originating from 5 species of freshwater fish, i.e., Esomus metallicus, Puntius brevis, Anabas testudineus, Parambassis siamensis, and Carassius auratus, in Chiang Mai province, Thailand. Sequence-related amplified polymorphism (SRAP) and phylogeny based on internal transcribed spacer 2 (ITS2) and mitochondrial cytochrome c oxidase subunit 1 (CO1) were performed. The results showed similar morphologies of adult C. formosanus from day 5 after infection in chicks. C. formosanus originated from 4 species of freshwater fish had the same number of circumoral spines on the oral sucker, except for those from C. auratus which revealed 34 circumoral spines. The phylogenetic tree obtained from SRAP profile and the combination of ITS2 and CO1 sequence showed similar results that were correlated with the number of circumoral spines in adult worms. Genetic variability of C. formosanus also occurred in different species of freshwater fish hosts. However, more details of adult worm morphologies and more sensitive genetic markers are needed to confirm the species validity of C. formosanus with 34 circumoral spines originating from C. auratus in the future. PMID:28285504

  11. Molecular Phylogenetics of Centrocestus formosanus (Digenea: Heterophyidae) Originated from Freshwater Fish from Chiang Mai Province, Thailand.

    Science.gov (United States)

    Wongsawad, Chalobol; Wongsawad, Pheravut; Sukontason, Kom; Maneepitaksanti, Worawit; Nantarat, Nattawadee

    2017-02-01

    This study aimed to investigate the morphology and reconstruct the phylogenetic relationships of Centrocestus formosanus originating from 5 species of freshwater fish, i.e., Esomus metallicus, Puntius brevis, Anabas testudineus, Parambassis siamensis, and Carassius auratus, in Chiang Mai province, Thailand. Sequence-related amplified polymorphism (SRAP) and phylogeny based on internal transcribed spacer 2 (ITS2) and mitochondrial cytochrome c oxidase subunit 1 (CO1) were performed. The results showed similar morphologies of adult C. formosanus from day 5 after infection in chicks. C. formosanus originated from 4 species of freshwater fish had the same number of circumoral spines on the oral sucker, except for those from C. auratus which revealed 34 circumoral spines. The phylogenetic tree obtained from SRAP profile and the combination of ITS2 and CO1 sequence showed similar results that were correlated with the number of circumoral spin