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Sample records for monoecious hydrilla hydrilla

  1. Surveys for Pathogens of Monoecious Hydrilla

    Science.gov (United States)

    2014-01-01

    purpose of the study presented herein was to survey some known populations of monoecious hydrilla and isolate potential fungal pathogens. MATERIALS ...sporulating species herein noted as dematiaceous (dark mycelium ) or moniliaceous (hyaline mycelium ) Ascomycetes (Table 1). The majority of the species

  2. Surveys for Pathogens of Monoecious Hydrilla 2014

    Science.gov (United States)

    2016-06-01

    hypothesized that the growth and reproductive habits were adaptations to northern climates, which suggests a temperate origin of the plant that was...it was only mildly pathogenic; but when it was inoculated onto plants that were endophyte-infected, the stressed plants usually died. These...Netherland, and Zack Banks for collecting monoecious hydrilla samples. Thanks also go to Michael Grodowitz and Lynde Dodd for reviewing the manuscript

  3. Surveys for Pathogens of Monoecious Hydrilla in 2013

    Science.gov (United States)

    2014-10-01

    2013, monoecious hydrilla was collected in the field from Strom Thurmond Reservoir in South Carolina/ Georgia , Lake Guntersville in Alabama, and Lake...Gainesville, Florida where monoecious hydrilla plants collected in Missouri, Kansas, South Carolina/ Georgia (Strom Thurmond Reservoir), and North...species” was plated onto Potato Carrot Agar (PCA; Dhingra and Sinclair 1995) and PDA and incubated at 25 oC under a grow light (plant aquarium wide

  4. Surveys for Biological Control Agents of Hydrilla verticillata in the People’s Republic of China in 2013

    Science.gov (United States)

    2017-03-01

    monoecious hydrilla is widely recognized as a relatively recent introduction. It was first discovered in Delaware in 1976 (Steward et al. 1984) and has...UNCLASSIFIED c. THIS PAGE UNCLASSIFIED 54 19b. TELEPHONE NUMBER (include area code) Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std . 239.18

  5. Life cycle assessment of nutrient remediation and bioenergy production potential from the harvest of hydrilla (Hydrilla verticillata).

    Science.gov (United States)

    Evans, Jason M; Wilkie, Ann C

    2010-12-01

    Hydrilla (Hydrilla verticillata) is one of the world's most problematic invasive aquatic plants. Although management of hydrilla overgrowth has often been based on use of chemical herbicides, issues such as the emergence of herbicide-resistant hydrilla biotypes and the need for in situ nutrient remediation strategies have together raised interest in the use of harvester machines as an alternative management approach. Using a life cycle assessment (LCA) approach, we calculated a range of net energy and economic benefits associated with hydrilla harvests and the utilization of biomass for biogas and compost production. Base case scenarios that used moderate data assumptions showed net energy benefit ratios (NEBRs) of 1.54 for biogas production and 1.32 for compost production pathways. NEBRs for these respective pathways rose to 2.11 and 2.68 when labor was excluded as a fossil fuel input. Base case biogas and compost production scenarios respectively showed a monetary benefit cost ratio (BCR) of 1.79 and 1.83. Moreover, very high NEBRs (3.94 for biogas; 6.37 for compost) and BCRs (>11 for both biogas and compost) were found for optimistic scenarios in which waterways were assumed to have high hydrilla biomass density, high nutrient content in biomass, and high priority for nutrient remediation. Energy and economic returns were largely decoupled, with biogas and fertilizer providing the bulk of output energy, while nutrient remediation and herbicide avoidance dominated the economic output calculations. Based on these results, we conclude that hydrilla harvest is likely a suitable and cost-effective management program for many nutrient-impaired waters. Additional research is needed to determine how hydrilla harvesting programs may be most effectively implemented in conjunction with fish and wildlife enhancement objectives.

  6. Combining Plant Pathogenic Fungi and the Leaf-Mining Fly, Hydrellia pakistanae, Increases Damage to Hydrilla

    OpenAIRE

    2003-01-01

    Four fungal species, F71PJ Acremonium sp., F531 Cylindrocarpon sp., F542, Botrytis sp., and F964 Fusarium culmorum [Wm. G. Sm.] Sacc. were recovered from hydrilla [ Hydrilla verticillata (L. f.) Royle] shoots or from soil and water surrounding hydrilla growing in ponds and lakes in Florida and shown to be capable of killing hydrilla in a bioassay. The isolates were tested singly and in combination with the leaf-mining fly, Hydrellia pakistanae ...

  7. Spectral signatures of hydrilla from a tank and field setting

    Institute of Scientific and Technical Information of China (English)

    Alfonso BLANCO; John J.QU; William E.ROPER

    2012-01-01

    The invasion of hydrilla in many waterways has caused significant problems resulting in high maintenance costs for eradicating this invasive aquatic weed.Present identification methods employed for detecting hydrilla invasions such as aerial photography and videos are difficult,costly,and time consuming.Remote sensing has been used for assessing wetlands and other aquatic vegetation,but very little information is available for detecting hydrilla invasions in coastal estuaries and other water bodies.The objective of this study is to construct a library of spectral signatures for identifying and classifying hydrilla invasions.Spectral signatures of hydrilla were collected from an experimental tank and field locations in a coastal estuary in the upper Chesapeake Bay.These measurements collected from the experimental tank,resulted in spectral signatures with an average peak surface reflectance in the near-infrared (NIR) region of 16% at a wavelength of 818 nm.However,the spectral measurements,collected in the estuary,resulted in a very different spectral signature with two surface reflectance peaks of 6% at wavelengths of 725 nm and 818 nm.The difference in spectral signatures between sites are a result of the components in the water column in the estuary because of increased turbidity (e.g.,nutrients,dissolved matter and suspended matter),and canopy being lower (submerged) in the water column.Spectral signatures of hydrilla observed in the tank and the field had similar characteristics with low reflectance in visible region of the spectrum from 400 to 700 nm,but high in the NIR region from 700 to 900 nm.

  8. Overseas Surveys (1981-1983) for Insects to Control Hydrilla.

    Science.gov (United States)

    1985-12-01

    several treatments usually required during the growing season, only high priority waters can be effectively managed. Taxonomy Identification difficulties...11. Hydrilla has been recognized as a separate species of plant since the early days of taxonomy . According to Cook and Luond’s (1982) synonomy...Order Tanaidacea Tanaids Philippines 5 LUZ32Z1, LUZ832Z2 Total 105 Glass Mollusca Order Gastropoda (Snails) Ampullariidae Burma 3 BUR82204 Malaysia I

  9. Phytofabrication of silver nanoparticles by using aquatic plant Hydrilla verticilata

    Directory of Open Access Journals (Sweden)

    MAHENDRA RAI

    2012-07-01

    Full Text Available Sable N, Gaikwad S, Bonde S, Gade A, Rai M. 2012. Phytofabrication of silver nanoparticles by using aquatic plant Hydrilla verticilata. Nusantara Bioscience 4: 45-49. In the context of current drive to developed new green technology in nanomaterials, synthesis of nanoparticles is of considerable importance. There has been considerable work done in the field of nanoscience and nanotechnology during the last decade due to the introduction of various protocols for the synthesis of nanoparticles by using plants and microorganisms. Here we firstly report the extracellular phytosynthesis of silver nanoparticles (Ag-NPs using aquatic plants Hydrilla verticilata. The characterization of the phytosynthesized Ag-NPs was done with the help of UV-Vis spectroscopy, FTIR, Nanoparticle Tracking Analysis (NTA, Zeta potential and SEM. The SEM micrograph revealed the synthesis of polydispersed spherical nanoparticles, with the average size of 65.55 nm. The phytofabricated Ag-NPs can be used in the field of medicine and agriculture, due to their antimicrobial potential.

  10. Mass-Rearing Hydrellia Pakistanae Deonier and H. balciunasi Bock for the Management of Hydrilla verticillata

    Science.gov (United States)

    2009-06-01

    provided on rearing methods, releases, and associated costs. BACKGROUND: Hydrilla, family Hydrocharitaceae, is an exotic submersed macrophyte that...amount of topped-out, contiguous hydrilla was noted, as was the location within the reservoir (cove, boat lane, etc.). Sites containing large...as Berlese extraction with the same methods previously mentioned to monitor rearing pond numbers. Generally, two or three sites per reservoir were

  11. An extract of Hydrilla verticillata and associated epiphytes induces avian vacuolar myelinopathy in laboratory mallards.

    Science.gov (United States)

    Wiley, Faith E; Twiner, Michael J; Leighfield, Tod A; Wilde, Susan B; Van Dolah, Frances M; Fischer, John R; Bowerman, William W

    2009-08-01

    Avian vacuolar myelinopathy (AVM) is a neurological disease affecting bald eagles (Haliaeetus leucocephalus), American coots (Fulica americana), waterfowl, and other birds in the southeastern United States. The cause of the disease is unknown, but is thought to be a naturally produced toxin. AVM is associated with aquatic macrophytes, most frequently hydrilla (Hydrilla verticillata), and researchers have linked the disease to an epiphytic cyanobacterial species associated with the macrophytes. The goal of this study was to develop an extraction protocol for separating the putative toxin from a hydrilla-cyanobacterial matrix. Hydrilla samples were collected from an AVM-affected reservoir (J. Strom Thurmond Lake, SC) and confirmed to contain the etiologic agent by mallard (Anas platyrhynchos) bioassay. These samples were then extracted using a solvent series of increasing polarity: hexanes, acetone, and methanol. Control hydrilla samples from a reference reservoir with no history of AVM (Lake Marion, SC) were extracted in parallel. Resulting extracts were administered to mallards by oral gavage. Our findings indicate that the methanol extracts of hydrilla collected from the AVM-affected site induced the disease in laboratory mallards. This study provides the first data documenting for an "extractable" AVM-inducing agent.

  12. Experimental feeding of Hydrilla verticillata colonized by stigonematales cyanobacteria induces vacuolar myelinopathy in painted turtles (Chrysemys picta.

    Directory of Open Access Journals (Sweden)

    Albert D Mercurio

    Full Text Available Vacuolar myelinopathy (VM is a neurologic disease primarily found in birds that occurs when wildlife ingest submerged aquatic vegetation colonized by an uncharacterized toxin-producing cyanobacterium (hereafter "UCB" for "uncharacterized cyanobacterium". Turtles are among the closest extant relatives of birds and many species directly and/or indirectly consume aquatic vegetation. However, it is unknown whether turtles can develop VM. We conducted a feeding trial to determine whether painted turtles (Chrysemys picta would develop VM after feeding on Hydrilla (Hydrilla verticillata, colonized by the UCB (Hydrilla is the most common "host" of UCB. We hypothesized turtles fed Hydrilla colonized by the UCB would exhibit neurologic impairment and vacuolation of nervous tissues, whereas turtles fed Hydrilla free of the UCB would not. The ability of Hydrilla colonized by the UCB to cause VM (hereafter, "toxicity" was verified by feeding it to domestic chickens (Gallus gallus domesticus or necropsy of field collected American coots (Fulica americana captured at the site of Hydrilla collections. We randomly assigned ten wild-caught turtles into toxic or non-toxic Hydrilla feeding groups and delivered the diets for up to 97 days. Between days 82 and 89, all turtles fed toxic Hydrilla displayed physical and/or neurologic impairment. Histologic examination of the brain and spinal cord revealed vacuolations in all treatment turtles. None of the control turtles exhibited neurologic impairment or had detectable brain or spinal cord vacuolations. This is the first evidence that freshwater turtles can become neurologically impaired and develop vacuolations after consuming toxic Hydrilla colonized with the UCB. The southeastern United States, where outbreaks of VM occur regularly and where vegetation colonized by the UCB is common, is also a global hotspot of freshwater turtle diversity. Our results suggest that further investigations into the effect of the

  13. Experimental feeding of Hydrilla verticillata colonized by stigonematales cyanobacteria induces vacuolar myelinopathy in painted turtles (Chrysemys picta).

    Science.gov (United States)

    Mercurio, Albert D; Hernandez, Sonia M; Maerz, John C; Yabsley, Michael J; Ellis, Angela E; Coleman, Amanda L; Shelnutt, Leslie M; Fischer, John R; Wilde, Susan B

    2014-01-01

    Vacuolar myelinopathy (VM) is a neurologic disease primarily found in birds that occurs when wildlife ingest submerged aquatic vegetation colonized by an uncharacterized toxin-producing cyanobacterium (hereafter "UCB" for "uncharacterized cyanobacterium"). Turtles are among the closest extant relatives of birds and many species directly and/or indirectly consume aquatic vegetation. However, it is unknown whether turtles can develop VM. We conducted a feeding trial to determine whether painted turtles (Chrysemys picta) would develop VM after feeding on Hydrilla (Hydrilla verticillata), colonized by the UCB (Hydrilla is the most common "host" of UCB). We hypothesized turtles fed Hydrilla colonized by the UCB would exhibit neurologic impairment and vacuolation of nervous tissues, whereas turtles fed Hydrilla free of the UCB would not. The ability of Hydrilla colonized by the UCB to cause VM (hereafter, "toxicity") was verified by feeding it to domestic chickens (Gallus gallus domesticus) or necropsy of field collected American coots (Fulica americana) captured at the site of Hydrilla collections. We randomly assigned ten wild-caught turtles into toxic or non-toxic Hydrilla feeding groups and delivered the diets for up to 97 days. Between days 82 and 89, all turtles fed toxic Hydrilla displayed physical and/or neurologic impairment. Histologic examination of the brain and spinal cord revealed vacuolations in all treatment turtles. None of the control turtles exhibited neurologic impairment or had detectable brain or spinal cord vacuolations. This is the first evidence that freshwater turtles can become neurologically impaired and develop vacuolations after consuming toxic Hydrilla colonized with the UCB. The southeastern United States, where outbreaks of VM occur regularly and where vegetation colonized by the UCB is common, is also a global hotspot of freshwater turtle diversity. Our results suggest that further investigations into the effect of the putative UCB toxin

  14. Establishing Research and Management Priorities for Monoecious Hydrilla

    Science.gov (United States)

    2014-01-01

    between the biotypes were successful and variations of these early tests are in use today (Ryan et al. 1991; Madeira et al. 2004; Rybicki et al. 2013...Management Society awarded a graduate student stipend to Dr. Rob Richardson at North Carolina State University (NCSU) to evaluate the phenology and...optimal treatment timing require additional information on tuber sprouting dynamics (e.g. plant phenology information described above would provide

  15. Captive bubble and sessile drop surface characterization of a submerged aquatic plant, Hydrilla verticillata

    Science.gov (United States)

    The surface energy parameters of the invasive aquatic weed, Hydrilla verticillata, were determined using contact angle measurements using two different methods. The abaxial and adaxial surfaces of the leaves and stem were characterized for the weed while submerged in water using captive air and octa...

  16. Biological Control Agents of Hydrilla Verticillata; Final Report on Surveys in East Africa, 1981-1984.

    Science.gov (United States)

    1986-07-01

    eastern arm of the Rift Valley are mainly "soda" lakes (Magadi, Elmenteita, Nakuru, and Bogoria ), which are too saline to support aquatic macrophytes...J.A Lakes Magadi, Elmenteita, Nakuru, Bogoria , Turkana - no hydrilla Soda lakes of eastern Rift. First four too saline to support any submerged...inued). distribution in Uganda ( Lake Kioga), Rwanda ( Lake Bulera and Mukungwa River), and Burundi ( Lake Tanganyika). In Kenya, despite an intensive

  17. Field Surveys to Identify Biocontrol Agents of Hydrilla verticillata from June - September 2012

    Science.gov (United States)

    2015-07-01

    recreational uses, out-competes native vegetation, acts as a breeding ground for mosquitoes , and destroys fish and wildlife habitats. Hydrilla is...1 Invasion Biology and Biocontrol Lab, Wuhan Botanical Institute, CAS ERDC/TN APCRP-BC-36 July 2015 3 named previously as Bagous sp. 3 and...Continued exploration will be conducted in Guangxi Province to find new agents. ERDC/TN APCRP-BC-36 July 2015 9 Rearing, biology , and host

  18. A CO2-flux mechanism operating via pH-polarity in Hydrilla verticillata leaves with C-3 and C-4 photosynthesis

    NARCIS (Netherlands)

    van Ginkel, LC; Bowes, G; Reiskind, JB; Prins, HBA

    2001-01-01

    The aquatic angiosperm Hydrilla verticillata lacks Kranz anatomy, but has an inducible, C-4-based, CO2 concentrating mechanism (CCM) that concentrates CO2 in the chloroplasts. Both C-3 and C-4 Hydrilla leaves showed light-dependent pH polarity that was suppressed by high dissolved inorganic carbon (

  19. A social analysis of the bioinvasions of Dreissena polymorpha in Spain and Hydrilla verticillata in Guatemala.

    Science.gov (United States)

    Binimelis, Rosa; Monterroso, Iliana; Rodríguez-Labajos, Beatriz

    2007-10-01

    Human agency plays a key role in the processes of biological invasions. This comprises not only the human role in the configuration of driving forces or in the perception of the impacts, but also the conceptualization of alien species themselves as an environmental problem. This paper examines different stakeholders' positions in bioinvasion processes at different scales, and it looks at their relevance for the management of invasive species. It compares two cases: the invasion process of Dreissena polymorpha in the Ebro River in Spain and the case of Hydrilla verticillata in Lake Izabal, Guatemala. Our results are structured according to impacts and to management options. The discussion focuses on the relevance of incorporating the different stakeholders' interests and values in the analysis and management of biological invasions. Although social analysis of stakeholders' positions is necessary in order to foster management actions, it also reveals conflicts on the relevant criteria and on the very definition of invasive species.

  20. A Social Analysis of the Bioinvasions of Dreissena polymorpha in Spain and Hydrilla verticillata in Guatemala

    Science.gov (United States)

    Binimelis, Rosa; Monterroso, Iliana; Rodríguez-Labajos, Beatriz

    2007-10-01

    Human agency plays a key role in the processes of biological invasions. This comprises not only the human role in the configuration of driving forces or in the perception of the impacts, but also the conceptualization of alien species themselves as an environmental problem. This paper examines different stakeholders’ positions in bioinvasion processes at different scales, and it looks at their relevance for the management of invasive species. It compares two cases: the invasion process of Dreissena polymorpha in the Ebro River in Spain and the case of Hydrilla verticillata in Lake Izabal, Guatemala. Our results are structured according to impacts and to management options. The discussion focuses on the relevance of incorporating the different stakeholders’ interests and values in the analysis and management of biological invasions. Although social analysis of stakeholders’ positions is necessary in order to foster management actions, it also reveals conflicts on the relevant criteria and on the very definition of invasive species.

  1. The phylogeographic structure of Hydrilla verticillata (Hydrocharitaceae) in China and its implications for the biogeographic history of this worldwide-distributed submerged macrophyte.

    Science.gov (United States)

    Zhu, Jinning; Yu, Dan; Xu, Xinwei

    2015-05-24

    Aquatic vascular plants are a distinctive group, differing from terrestrial plants in their growth forms and habitats. Among the various aquatic plant life forms, the evolutionary processes of freshwater submerged species are most likely distinct due to their exclusive occurrence in the discrete and patchy aquatic habitats. Using the chloroplast trnL-F region sequence data, we investigated the phylogeographic structure of a submerged macrophyte, Hydrilla verticillata, the single species in the genus Hydrilla, throughout China, in addition to combined sample data from other countries to reveal the colonisation and diversification processes of this species throughout the world. We sequenced 681 individuals from 123 sampling locations throughout China and identified a significant phylogeographic structure (NST > GST, p China indicates that China is most likely the centre of Hydrilla genetic diversity. The worldwide distribution of Hydrilla is due to recent vicariance and dispersal events that occurred in different clades during the Pleistocene. Our findings also provide useful information for the management of invasive Hydrilla in North America.

  2. Application of ADM1 for modeling of biogas production from anaerobic digestion of Hydrilla verticillata.

    Science.gov (United States)

    Chen, Xiaojuan; Chen, Zhihua; Wang, Xun; Huo, Chan; Hu, Zhiquan; Xiao, Bo; Hu, Mian

    2016-07-01

    The present study focused on the application of anaerobic digestion model no. 1 (ADM1) to simulate biogas production from Hydrilla verticillata. Model simulation was carried out by implementing ADM1 in AQUASIM 2.0 software. Sensitivity analysis was used to select the most sensitive parameters for estimation using the absolute-relative sensitivity function. Among all the kinetic parameters, disintegration constant (kdis), hydrolysis constant of protein (khyd_pr), Monod maximum specific substrate uptake rate (km_aa, km_ac, km_h2) and half-saturation constants (Ks_aa, Ks_ac) affect biogas production significantly, which were optimized by fitting of the model equations to the data obtained from batch experiments. The ADM1 model after parameter estimation was able to well predict the experimental results of daily biogas production and biogas composition. The simulation results of evolution of organic acids, bacteria concentrations and inhibition effects also helped to get insight into the reaction mechanisms. Copyright © 2016. Published by Elsevier Ltd.

  3. Interspecific competition effects on phosphorus accumulation by Hydrilla verticillata and Vallisneria natans

    Institute of Scientific and Technical Information of China (English)

    Xiufeng Zhang; Zhengwen Liu

    2011-01-01

    The competition between submersed plants has been recognized as an important factor influencing the structure of plant communities in shallow lakes.The ability of different species to take up and store nutrients from the surrounding ambience varies,and hence plant community structure might be expected to affect the cycling of nutrients in lake ecosystems.In this study,the uptake of phosphorus by Hydrilla verticillata and Vallisneria natans was studied and compared in monoculture and competitive mixed-culture plantings.Results showed that for both studied species the phosphorus concentrations of different tissues and of whole plants was unaffected by competition.However,the quantity of phosphorus accumulated by whole plants of H.verticillata was significantly higher in mixture culture than in monoculture,while that of V.natans was lower in the mixed culture.The results indicated that H.verticillata has a competitive advantage over V.natant,when the two species are grown in competition,and is able to accumulate a greater quantity of phosphorus.

  4. Evaluation of uranium removal by Hydrilla verticillata (L.f.) Royle from low level nuclear waste under laboratory conditions.

    Science.gov (United States)

    Srivastava, Sudhakar; Bhainsa, K C

    2016-02-01

    The present study evaluated uranium (U) removal ability and tolerance to low level nuclear waste (LLNW) of an aquatic weed Hydrilla verticillata. Plants were screened for growth in 10%-50% waste treatments up to 3 d. Treatments of 20% and 50% waste imposed increasing toxicity with duration assessed in terms of change in fresh weight and in the levels of photosynthetic pigments and thiobarbituric acid-reactive substances. U concentration, however, did not show a progressive increase and was about 42 μg g(-1) dw from 20% to 50% waste at 3 d. This suggested that a saturation stage was reached with respect to U removal due to increasing toxicity. However, in another experiment with 10% waste and 10% waste+10 ppm U treatments, plants showed an increase in U concentration with the maximum level approaching 426 μg g(-1) dw at 3 d without showing any toxicity as compared to that at 20% and 50% waste treatments. Hence, plants possessed significant potential to take up U and toxicity of LLNW limited their U removal ability. This implies that the use of Hydrilla plants for U removal from LLNW is feasible at low concentrations and would require repeated harvesting at short intervals.

  5. New methods for the analysis of invasion processes: multi-criteria evaluation of the invasion of Hydrilla verticillata in Guatemala.

    Science.gov (United States)

    Monterroso, I; Binimelis, R; Rodríguez-Labajos, B

    2011-03-01

    The study described in this article incorporates stakeholders' views on aquatic invasion processes and combines expert analysis with information from field work into an evaluation exercise. Management scenarios are designed based on available technical data and stakeholders' perceptions. These scenarios are evaluated using the Social Multi-Criteria Evaluation framework employing the NAIADE model. Two evaluations are carried out, technical and social. Social acceptance of different management scenarios, distribution of costs and benefits, and attribution of responsibility are discussed. The case study was carried out on Lake Izabal, a body of water connected to the Caribbean Sea in Northeastern Guatemala. In 2000, local fishermen reported the presence of an alien species in the lake, the macrophyte Hydrilla verticillata. Two years later, this alien species was established around the entire lakeshore, damaging the ecosystem, endangering native species and the subsistence of local inhabitants through impacts on transportation, fishing practices, and tourism.

  6. The Ontogeny of Hydrilla verticillata(L.f.)Royle%黑藻早期个体发育的研究

    Institute of Scientific and Technical Information of China (English)

    刘玫; 王臣; 刘鸣远

    2007-01-01

    对黑藻(Hydrilla verticillata)个体发育中的胚胎发育(从合子到种子胚)和种苗发育(从种子到种苗)进行了研究.发现沉水植物黑藻与挺水植物泽泻(Alisma orientale)在胚柄只有1~2个细胞、种子胚苗端发达根端未分化、萌发后根端始分化、分生区之上产生根环与下胚轴毛、初生根短命等特点上基本相同,并对这些特点进行了讨论.

  7. Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands

    Institute of Scientific and Technical Information of China (English)

    XU Qiu-jin; NIAN Yue-gang; JIN Xiang-can; YAN Chang-zhou; LIU Jin; Jiang Gao-ming

    2007-01-01

    Effects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. verticillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD (980 mg/L) and decreased with low COD (63 mg/L), respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant cells from the control experiment (untreated with chitosan) were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.

  8. Evaluation of peroxidase as a biochemical indicator of toxic chemical exposure in the aquatic plant Hydrilla verticillata, Royle

    Science.gov (United States)

    Byl, T.D.; Sutton, H.D.; Klaine, S.J.

    1994-01-01

    Laboratory bioassays were conducted to determine the utility of peroxidase (POD) activity as a biochemical indicator of contaminant exposure in the aquatic plant Hydrilla verticillata, Royle. The plants were exposed to anthracene, sulfometuron methyl (Oust??), Cd2+, Cr6+, Cu2+, Mn2+, and Se4+ in concentration factors of 10. POD was extracted and measured by spectrophotometric assay. There was a significant increase in POD activity after a 5-d exposure to each of the chemicals at 1 mg/L. The optimum pH for POD activity after exposure to the chemicals was 5.5 to 6.0. The increase in POD was found to be dose dependent for each of the chemicals. The lowest concentration of chemical to induce a significant POD increase was 0.01 mg/L for anthracene, Oust, Cd, Cr, and Cu; 0.1 mg/L for Se; and 1.0 mg/L for Mn.Laboratory bioassays were conducted to determine the utility of peroxidase (POD) activity as a biochemical indicator of contaminant exposure in the aquatic plant Hydrilla verticillata, Royle. The plants were exposed to anthracene, sulfometuron methyl (Oust), Cd2+, Cr6+, Cu2+, Mn2+, and Se4+ in concentration factors of 10. POD was extracted and measured by spectrophotometric assay. There was a significant increase in POD activity after a 5-d exposure to each of the chemicals at 1 mg/L. The optimum pH for POD activity after exposure to the chemicals was 5.5 to 6.0. The increase in POD was found to be dose dependent for each of the chemicals. The lowest concentration of chemical to induce a significant POD increase was 0.01 mg/L for anthracene, Oust, Cd, Cr, and Cu: 0.1 mg/L for Se; and 1.0 mg/L for Mn.

  9. Packed-bed column biosorption of chromium(VI) and nickel(II) onto Fenton modified Hydrilla verticillata dried biomass.

    Science.gov (United States)

    Mishra, Ashutosh; Tripathi, Brahma Dutt; Rai, Ashwani Kumar

    2016-10-01

    The present study represents the first attempt to investigate the biosorption potential of Fenton modified Hydrilla verticillata dried biomass (FMB) in removing chromium(VI) and nickel(II) ions from wastewater using up-flow packed-bed column reactor. Effects of different packed-bed column parameters such as bed height, flow rate, influent metal ion concentration and particle size were examined. The outcome of the column experiments illustrated that highest bed height (25cm); lowest flow rate (10mLmin(-1)), lowest influent metal concentration (5mgL(-1)) and smallest particle size range (0.25-0.50mm) are favourable for biosorption. The maximum biosorption capacity of FMB for chromium(VI) and nickel(II) removal were estimated to be 89.32 and 87.18mgg(-1) respectively. The breakthrough curves were analyzed using Bed Depth Service Time (BDST) and Thomas models. The experimental results obtained agree to both the models. Column regeneration experiments were also carried out using 0.1M HNO3. Results revealed good reusability of FMB during ten cycles of sorption and desorption. Performance of FMB-packed column in treating secondary effluent was also tested under identical experimental conditions. Results demonstrated significant reduction in chromium(VI) and nickel(II) ions concentration after the biosorption process.

  10. Removal of Organochlorine Pesticides by Hydrilla verticillata%黑藻对有机氯农药去除特性研究

    Institute of Scientific and Technical Information of China (English)

    迟杰; 张雷; 吴万秀

    2011-01-01

    The potential function of hydrophytes for field bioremediation has been more and more concerned. In this work, a common hydrophyte, Hydrilla verticillata was selected to investigate its ability to remove α-HCH, γ-HCH and p,p'-DDT. The results showed that the biodegradation of α-HCH, γ-HCH and p,p'-DDT by Hydrilla verticillata followed first-order kinetics, and biodegradation rate constants were 0.086, 0.103 d-1 and 0.077 d-1, respectively. The bioconcentration factors of α-HCH, γ-HCH and p,p'-DDT by Hydrilla verticillata were significantly higher than 1, and in the order of p,p'-DDT>γ-HCH>α-HCH, α-HCH, γ-HCH and p,p'-DDT were mainly enriched in leaf. p,p'-DDD, the anaerobic product of p,p'-DDT, was detected in the experiment samples.%水生植物在水体污染修复中所起的作用越来越受到关注.采用室内培养方法,选取常见水生植物黑藻对α-HCH、γ-HCH和p,p′-DDT的去除特性进行了研究.结果表明,黑藻对α-HCH、γ-HCH和p,p′-DDT的降解符合一级反应动力学,降解速率常数分别为0.086、0.103 d-1和0.077 d-1;α-HCH、γ-HCH和p,p′-DDT在黑藻中的富集系数均显著大于1,顺序为p,p′-DDT>γ-HCH>α-HCH,主要富集在叶中;实验样品中均检出有p,p′-DDT的厌氧降解产物p,p′-DDD生成.

  11. Redox state and energetic equilibrium determine the magnitude of stress in Hydrilla verticillata upon exposure to arsenate.

    Science.gov (United States)

    Srivastava, Sudhakar; Suprasanna, Penna; D'Souza, Stanislaus Francis

    2011-10-01

    Arsenic (As) is a potential hazard to plants' health, however the mechanisms of its toxicity are yet to be properly understood. To determine the impact of redox state and energetic in stress imposition, plants of Hydrilla verticillata (L.f.) Royle, which are known to be potential accumulator of As, were exposed to 100 and 500 μM arsenate (AsV) for 4 to 96 h. Plants demonstrated significant As accumulation with the maximum being at 500 μM after 96 h (568 μg g(-1) dry weight, dw). The accumulation of As led to a significant increase in the level of reactive oxygen species, nitric oxide, carbonyl, malondialdehyde, and percentage of DNA degradation. In addition, the activity of pro-oxidant enzymes like NADPH oxidase and ascorbate oxidase also showed significant increases. These parameters collectively indicated oxidative stress, which in turn caused an increase in percentage of cell death. These negative effects were seemingly linked to an altered energetic and redox equilibrium [analyzed in terms of ATP/ADP, NADH/NAD, NADPH/NADP, reduced glutathione/oxidized glutathione, and ascorbate/dehydroascobate ratios]. Although there was significant increase in the levels of phytochelatins, the As chelating ligands, a large amount of As was presumably present as free ion particularly at 500 μM AsV, which supposedly produced toxic responses. In conclusion, the study demonstrated that the magnitude of disturbance to redox and energetic equilibrium of plants upon AsV exposure determines the extent of toxicity to plants.

  12. Copper-induced oxidative stress and responses of antioxidants and phytochelatins in Hydrilla verticillata (L.f.) Royle.

    Science.gov (United States)

    Srivastava, Sudhakar; Mishra, Seema; Tripathi, Rudra D; Dwivedi, Sanjay; Gupta, Dharmendra K

    2006-12-30

    Copper, though essential, is potentially toxic heavy metal at supraoptimal level and has widespread contamination. The present investigation was carried out to study the responses induced by lower as well as higher doses of copper (0.1-25 microM) in an aquatic macrophyte, Hydrilla verticillata (L.f.) Royle for a period of 1-7 days. The plants accumulated copper in high amount with a maximum of 770 microg g(-1) dw on day 7 at 25 microM. Biomass and photosynthetic pigments showed less alteration up to 1 microM while at higher concentrations, significant decline occurred. Malondialdehyde (MDA) content and electrical conductivity (EC) also showed sharp increase at higher concentrations indicating oxidative stress. In response to copper exposure, plants showed significant induction of proteins and enzymes like superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), catalase (CAT) and glutathione reductase (GR), however, only up to moderate exposures. Total non-protein thiols (NP-SH) and cysteine levels increased significantly up to 5 microM copper exposure while at 25 microM, their level declined drastically. Reduced glutathione (GSH) showed decrease at all concentrations while oxidized glutathione (GSSG) simultaneously increased. Phytochelatins (PCs) were also induced significantly at studied concentrations of 1 and 5 microM on day 4 in comparison to control. However, copper chelation depicted by PC-SH to copper ratio was found to be low (6.5% at 1 microM and 2.4% at 5 microM) suggesting that PCs play only a part in integrated mechanisms of copper homeostasis and detoxification. Tolerant response of plants to moderate copper exposures and high accumulation potential warrants their suitability for remediation of moderately copper polluted water bodies.

  13. Phytochelatins and antioxidant systems respond differentially during arsenite and arsenate stress in Hydrilla verticillata (L.f.) Royle.

    Science.gov (United States)

    Srivastava, S; Mishra, S; Tripathi, R D; Dwivedi, S; Trivedi, P K; Tandon, P K

    2007-04-15

    Serious contamination of aquatic systems by arsenic (As) in different parts of the world calls for the development of an in situ cost-effective phytoremediation technology. In the present investigation, plants of Hydrilla verticillata (L.f.) Royle were exposed to various concentrations of arsenate (As(V)) (0-250 microM) and arsenite (AsIII) (0-25 microM) and analyzed for accumulation responses vis-à-vis biochemical changes. Total As accumulation was found to be higher in plants exposed to AsIII (315 microg g(-1) dw at 25 microM) compared to As(V) (205 microg g(-1) dw at 250 microM) after 7 d of treatment. Plants tolerated low concentrations of As(III) and As(V) by detoxifying the metalloid through augmented synthesis of thiols such as phytochelatins and through increased activity of antioxidant enzymes. While As(V) predominantly stimulated antioxidant enzyme activity, As(III) primarily caused enhanced levels of thiols. The maximum amount of As chelated by PCs was found to be about 39% in plants exposed to As(III) (at 10 microM) and 35% in As(V) exposed plants (at 50 microM) after 4 d. Only the respective highest concentrations of As(III) (25 microM) and As(V) (250 microM) proved toxic for normal plant growth after prolonged treatment. Thus, H. verticillata forms a promising candidate for the phytoremediation of As contaminated water.

  14. Arsenic, Zinc, and Aluminium Removal from Gold Mine Wastewater Effluents and Accumulation by Submerged Aquatic Plants (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata

    Directory of Open Access Journals (Sweden)

    Ahmad Farid Abu Bakar

    2013-01-01

    Full Text Available The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata to be used for As, Al, and Zn phytoremediation was tested. The plants were exposed for 14 days under hydroponic conditions to mine waste water effluents in order to assess the suitability of the aquatic plants to remediate elevated multi-metals concentrations in mine waste water. The results show that the E. densa and H. verticillata are able to accumulate high amount of arsenic (95.2% and zinc (93.7% and resulted in a decrease of arsenic and zinc in the ambient water. On the other hand, C. piauhyensis shows remarkable aluminium accumulation in plant biomass (83.8% compared to the other tested plants. The ability of these plants to accumulate the studied metals and survive throughout the experiment demonstrates the potential of these plants to remediate metal enriched water especially for mine drainage effluent. Among the three tested aquatic plants, H. verticillata was found to be the most applicable (84.5% and suitable plant species to phytoremediate elevated metals and metalloid in mine related waste water.

  15. Phytotoxicity and accumulation of zinc oxide nanoparticles on the aquatic plants Hydrilla verticillata and Phragmites Australis: leaf-type-dependent responses.

    Science.gov (United States)

    Song, Uhram; Lee, Sunryung

    2016-05-01

    The phytotoxicity and accumulation of zinc oxide nanoparticles (ZnO NPs) on aquatic plant Hydrilla verticillata and Phragmites australis were investigated using mesocosms. The percentage of dissolved Zn in the ZnO NP treatment solutions was measured along with plant shoot growth, antioxidant enzyme activity, chlorophyll content, and Zn content. The dissolution rate of ZnO NPs in Hoagland solution was inversely related to the concentration. The submerged aquatic plant H. verticillata, growth was reduced during the early stages of the experiment when exposed to the highest ZnO NP concentration (1000 mg/L), whereas the emerged aquatic plant P. australis began to show significantly reduced growth after a few weeks. The measurements of chlorophyll content, antioxidant enzyme activity, and Zn accumulation showed that P. australis was adversely affected by NPs and absorbed more Zn than H. verticillata. The results indicated that physiological differences among aquatic plants, such as whether they use leaves or roots for nutrient and water uptake, led to differences in nanoparticle toxicity. Overall, High ZnO NP concentrations caused significant phytotoxicity on aquatic plants, and low concentrations caused unpredictable phytotoxicity. Therefore, the use and disposal of zinc oxide nanoparticles should be carefully monitored.

  16. Arsenic, zinc, and aluminium removal from gold mine wastewater effluents and accumulation by submerged aquatic plants (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata).

    Science.gov (United States)

    Abu Bakar, Ahmad Farid; Yusoff, Ismail; Fatt, Ng Tham; Othman, Faridah; Ashraf, Muhammad Aqeel

    2013-01-01

    The potential of three submerged aquatic plant species (Cabomba piauhyensis, Egeria densa, and Hydrilla verticillata) to be used for As, Al, and Zn phytoremediation was tested. The plants were exposed for 14 days under hydroponic conditions to mine waste water effluents in order to assess the suitability of the aquatic plants to remediate elevated multi-metals concentrations in mine waste water. The results show that the E. densa and H. verticillata are able to accumulate high amount of arsenic (95.2%) and zinc (93.7%) and resulted in a decrease of arsenic and zinc in the ambient water. On the other hand, C. piauhyensis shows remarkable aluminium accumulation in plant biomass (83.8%) compared to the other tested plants. The ability of these plants to accumulate the studied metals and survive throughout the experiment demonstrates the potential of these plants to remediate metal enriched water especially for mine drainage effluent. Among the three tested aquatic plants, H. verticillata was found to be the most applicable (84.5%) and suitable plant species to phytoremediate elevated metals and metalloid in mine related waste water.

  17. Elaboración de abono orgánico a partir de plantas acuáticas: Elodea (Hydrilla verticillata) y Jacinto o Lirio de agua (Eichhornia crassipes), procedentes del Lago de Coatepeque y Lago de Güija

    OpenAIRE

    Reyes de Cabrales, Cecilia Elizabeth

    2009-01-01

    El presente estudio tiene por finalidad elaborar un abono orgánico bajo la técnica de compostaje, conocida como proceso de descomposición aeróbica. Se realizaron tres formulaciones de abono a partir de las plantas acuáticas Elodea (Hydrilla verticillata) y Jacinto de agua (Eichhornia crassipes) en las siguientes proporciones: Elodea 100%, Jacinto de agua 100% y mezcla de ambas en una proporción de 50:50. A los abonos obtenidos se les realizaron análisis químico con la finalidad de cuantificar...

  18. Integrated role of ROS and Ca(+2) in blue light-induced chloroplast avoidance movement in leaves of Hydrilla verticillata (L.f.) Royle.

    Science.gov (United States)

    Majumdar, Arkajo; Kar, Rup Kumar

    2016-11-01

    Directional chloroplast photorelocation is a major physio-biochemical mechanism that allows these organelles to realign themselves intracellularly in response to the intensity of the incident light as an adaptive response. Signaling processes involved in blue light (BL)-dependent chloroplast movements were investigated in Hydrilla verticillata (L.f.) Royle leaves. Treatments with antagonists of actin filaments [2,3,5-triiodobenzoic acid (TIBA)] and microtubules (oryzalin) revealed that actin filaments, but not microtubules, play a pivotal role in chloroplast movement. Involvement of reactive oxygen species (ROS) in controlling chloroplast avoidance movement has been demonstrated, as exogenous H2O2 not only accelerated chloroplast avoidance but also could induce chloroplast avoidance even in weak blue light (WBL). Further support came from experiments with different ROS scavengers, i.e., dimethylthiourea (DMTU), KI, and CuCl2, which inhibited chloroplast avoidance, and from ROS localization using specific stains. Such avoidance was also partially inhibited by ZnCl2, an inhibitor of NADPH oxidase (NOX) as well as 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), a photosynthetic electron transport chain (ETC) inhibitor at PS II. However, methyl viologen (MV), a PS I ETC inhibitor, rather accelerated avoidance response. Exogenous calcium (Ca(+2)) induced avoidance even in WBL while inhibited chloroplast accumulation partially. On the other hand, chloroplast movements (both accumulation and avoidance) were blocked by Ca(+2) antagonists, La(3+) (inhibitor of plasma membrane Ca(+2) channel) and ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA, Ca(+2) chelator) while LiCl that affects Ca(+2) release from endosomal compartments did not show any effect. A model on integrated role of ROS and Ca(+2) (influx from apolastic space) in actin-mediated chloroplast avoidance has been proposed.

  19. The Comparative Study on Photosynthesis of Hydrilla verticillata and Vallisneria natans in the Different Depth%黑藻与苦草在不同水深下光合作用的比较研究

    Institute of Scientific and Technical Information of China (English)

    经博翰; 袁龙义

    2014-01-01

    Chosen the Wagouzi site with abundant submerged population in the Honghu Lake as a sampling region, the difference of photosynthesis of submerged macrophytes Hydrilla verticillata( L. f. )Royle and vallisneria natans ( Lour. )Hara which are high resistance and obsorption to the dirty water in Honghu Lake was designed to research their response in the 100 cm and 50 cm water depth by Diving-PAM apparatus. The results showed that the value of External Transfer Rate(ETR)of Hydrilla verticillata and vallisneria natans separately approached to 25. 1 μmol· m-2 · s-1 and 10 . 1 μmol · m-2 · s-1 when the value of Photosynthetic Active Radiation( PAR )was stable for 342 μmol·m-2 · s-1 under the condition of 100 cm water depth. With the PAr intensity gradually becoming strong,ETr of Hydrilla verticillata reached its peak 21. 76 μmol·m-2 ·s-1 when the PAr value was 219 μmol· m-2 ·s-1 ,as well as ETr of vallisneria natans reached its peak 12. 65 μmol·m-2 ·s-1 when the PAr value was 515 μmol·m-2 ·s-1 . On the other hand,the value of ETr of Hydrilla verticillata and vallisneria natans separately approached to 26. 2 μmol·m-2 ·s-1 and 11. 9 μmol·m-2 ·s-1 when the value of PAr was stable for 515 μmol· m-2 ·s-1 under the condition of 50 cm water depth. With the PAr intensity gradually becoming strong,ETr of Hydrilla verticillata reached its peak 25. 27 μmol·m-2 ·s-1 when the PAr value was 219 μmol·m-2 ·s-1 ,as well as ETr of vallisneria natans reached its peak 4. 80 μmol·m-2 ·s-1 when the PAr value was 1 042 μmol· m-2 ·s-1 . In summary,no matter in 100 cm or 50 cm water depth condition,photosynthesis intensity of Hydrilla verticillata is stronger than that of vallisneria natans.%以沉水植物较为丰富的洪湖凹沟子作为采样区域,利用水下调制荧光仪研究洪湖常见的2种高耐污、高吸污水鳖科沉水植物黑藻( Hydrilla verticillata( L. f.)Royle)与苦草( vallisneria natans( Lour

  20. Biological Studies of Bagous Hydrillae

    Science.gov (United States)

    1994-09-01

    garis L. cultivated beans Raphanus sativus L. cultivated radish Sedum sp. introduced, ornamental Sesuvium portulacastrum (L.)L. native Appencix A...watermelon Matsum. & Nakai var. lanatus Citrus sp. cultivated citrus Crassula argentea Thunb. introduced, ornamental Cucumis sativus L. cultivated cucumber

  1. 两种沉水植物黑藻和伊乐藻的种间竞争%INTER-SPECIFIC COMPETITION BETWEEN TWO SUBMERGED MACROPHYTES, ELODEA NUTTALLII AND HYDRILLA VERTICILLATA

    Institute of Scientific and Technical Information of China (English)

    许经伟; 李伟; 刘贵华; 张利静; 刘文治

    2007-01-01

    采用取代系列实验方法,主要从竞争期的长短出发,研究了黑藻(Hydrilla verticillata)和伊乐藻(Elodea nuttallii)的种间竞争关系,并考查了在不同底质(土壤)肥力下两者种间竞争能力的变化情况.实验发现,伊乐藻由于具有较强的耐寒能力,在冬春时空竞争方面占有明显的优势,从而在周年实验中表现出较强的竞争优势,取代黑藻生长.而在短期实验中,黑藻由于可在水面生长形成较上位的冠层的特性,与伊乐藻相比在水体上层空间占领和阳光获取方面具有一定的优势,因此造成两种间竞争的不平衡,竞争偏利于黑藻,且这种优势随底质(土壤)肥力的增加而有所增强,但并没有明显取代现象的发生,两物种可以在混合种群中共存.

  2. La descontaminación de las aguas del lago Izabal en Guatemala a través de la extracción de la planta Hydrilla verticillata (L.F Royle y su uso como sustrato alternativo para la producción de plántulas de chile pimiento en invernadero

    Directory of Open Access Journals (Sweden)

    Iván Dimitri Santos Castillo

    2010-01-01

    Full Text Available Se caracterizaron las principales propiedades físicas, químicas y biológicas de sustratos elaborados a base de residuos de hydrilla verticillata y su efecto sobre la germinación y desarrollo durante la fase de plántula de semillas de chile pimiento (variedad tropical irazú mejorado. Al analizar los resultados obtenidos tales como agua fácilmente aprovechable, capacidad de aereación, PH, porciento de germinación, germinación acumulada ( 24 DDS, altura de la planta (cm, diámetro del tallo (cm, peso fresco de la parte aérea y sistema radical (g, materia seca de la parte aérea y radical ( % , todo ello 50 días después de siembra (50 DDS, se obtiene que el mejor tratamiento bajo las condiciones y metodologías utilizadas es el N0 12 (H30-85-15, o sea, 85% de hydrilla con 30 días de compostaje + 15 % de perlita y se recomienda como sustituto alternativo del sustrato comercial (turba de sphagnum para la producción de plántulas de chile pimiento en pilones y con ello dar uso productivo a esta planta contaminante de los lagos de Guatemala.

  3. EFFECT OF LIGHT INTENSITY, TEMPERATURE, TOTAL NITROGEN CONCENTRATION AND THEIR INTERACTION ON HYDRILLA VERTICILLATA%光强、温度、总氮浓度对黑藻生长的影响

    Institute of Scientific and Technical Information of China (English)

    朱丹婷; 乔宁宁; 李铭红; 陈攀

    2011-01-01

    为寻求沉水植物生长的主效环境因子,探求富营养化水体沉水植物的衰亡机理并选择治理富营养化的先锋植物,实验选择长江中下游常见沉水植物种黑藻(Hydrilla verticillata),利用正交试验设计,通过室内静态模拟实验研究三种主要环境因子光照强度、温度、总氮浓度及其互作对黑藻断枝生长的影响.结果表明:光照强度和温度为影响黑藻生长的主效环境因子,并且光强与温度的交互作用对黑藻生长有较为显著的影响,具体表现为黑藻的生长指标(株高、生物量、分枝数)、光合指标(叶绿素a+b浓度、叶绿素a/b、叶绿体总色素含量)和生理活性指标(根活力、可溶性糖含量、MDA含量)的变化均与这两个环境因子及其互作呈显著相关;总氮浓度的变化对黑藻生长影响不大,在2-8 mg/L的总氮浓度下,黑藻均可以正常生长.根据本实验黑藻生长指标、光合色素含量以及生理活性在不同环境因子组合的变化结果可知,黑藻在5320-12000 lx光照强度、20℃-30℃、4-8 mg/L水体总氮浓度的条件下生长良好,故推测黑藻可作为春夏季富营养化水体中恢复和重建沉水植被的先锋工具种.%With the strengthening of freshwater eutrophication, the original aquatic vegetation gradually reduced and even disappeared, resulting in the well-functional grass type water degraded to algae-based water. Submerged plant is a key factor for the construction of stable and well-functioning freshwater ecosystems. Therefore, restoration and reconstruction of submerged plants is very important for prevention and control of eutrophication. The growth and development, decline and extinction of submerged plants are closely related with environmental factors due to their aquatic characteristics. In this study, we aim to explore the effects of light intensity, temperature, total nitrogen concentration and their interactions on the growth and development

  4. Effects of arsenic speciation on the phytochelatins (PCs) synthesis by Hydrilla verticillata%不同形态砷对黑藻植物络合素合成的影响

    Institute of Scientific and Technical Information of China (English)

    李红梅; 王宏镔; 王海娟; 宋雁辉; 钟正燕

    2012-01-01

    采用反相高效液相色谱(RP-HPLC)法,研究了水培条件下3种形态砷[三价砷As(Ⅲ)、五价砷As(Ⅴ)和二甲基砷(DMA)]的5个处理浓度(0、0.3、1.0、3.0和5.0 mg·L-1)对黑藻(Hydrilla venicillata(L.f.)Royle)砷吸收和植物络合素(PCs)合成的影响.结果表明:黑藻对As表现出明显的吸收和富集效应,低浓度As能促进黑藻生长,对As (Ⅲ)的吸收显著高于As(Ⅴ)和DMA;As(Ⅲ)和As(Ⅴ)处理显著诱导了谷胱甘肽(GSH)、PC2和PC4的合成,且与黑藻体内As含量呈显著正相关(P<0.05);PCs对DMA处理不敏感,只有在0.3 mg·L-1下能合成PCs;在As( Ⅲ)处理下,GSH和PC2的合成随As(Ⅲ)浓度的增加呈先增加后减少的趋势,而PC4的合成却随As(Ⅲ)浓度的增加而增加;在As(Ⅴ)处理下,GSH的合成随As(Ⅴ)浓度的增加呈先增加后减少的趋势,而PG2和PC4的合成则随As(Ⅴ)浓度的增加而增加;在3种形态As的不同浓度处理中PC3的合成很少,只在0.3 mg·L-1下有少量合成.研究结果表明,PCs对As( Ⅲ)和As(Ⅴ)的胁迫较敏感,可选择性地作为这2种形态砷胁迫下黑藻的生物标记物.%A hydroponie experiment was conducted to study the effects of different arsenic species [As(III), As(V), and DMA] at five concentrations (0, 0.3, 1.0, 3.0, and 5.0 mg· L-1) on the arsenic uptake and phytochelatins (PCs) synthesis by Hydrilla verticillaia. The PCs contents were identified by reversed phase-high performance liquid chromatography ( RP-HPLC). H. vertkillata had an obvious arsenic uptake and accumulation. Low concentrations arsenic promoted the growth of H. veniciilata, and the uptake of As( III) by H. vertkillata was significantly higher than that of As(V) or DMA. As(III) and As(V) promoted the synthesis of GSH, PC2, and PC4 significantly, and the synthesis was significantly positively correlated with the arsenic concentration in H. venkillala (P<0.05). DMA had little effects on the synthesis of PCs, with a detectable synthesis

  5. 沉水植物轮叶黑藻附生细菌对双酚A的降解能力研究%Degradation of bisphenol A by the epiphytic bacteria of submerged macrophytes Hydrilla verticillata (L. f.) Royle

    Institute of Scientific and Technical Information of China (English)

    张国森; 王玉; 庄晓瑾; 杨劭; 蒋金辉

    2016-01-01

    Epiphytic bacteria of submerged macrophytes may have the capability in biodegradation and/or biotransformation of bisphenol A (BPA) in water column, therefore affect the fate of such environmental pollutant. In this research,Hydrilla verticillata(L. f.) Royle was selected and their attached BPA degrading epiphytic bacteria attached were isolated. Among the 22bacteria strains, the BPA removal rates were from 11.46% to 25.06% with the inoculum density at 1×10-8cell/mL and culture at 37℃ for 72h. The most effective bacteria strains, B12, B14and B23 were identified asLysinibacillus sp.,Brevibacterium sp. andOchrobactrum sp., respectively, according to the results of 16S rDNA sequencing and morphological, physiological and biochemical tests. But aseptic seedlings ofH. verticillata significantly decreased their BPA removal rates after the addition with B12, B14and B23 (P<0.05). Natural seedlings of such species surprisingly increased about 5% in BPA removal after partially removing their epiphyte with physical methods. All the results indicated that epiphytic bacteria of submerged plant can remove BPA, although their contributions (about 23%) are less than the host plants in the submerged macrophytes-epiphyte associations.%沉水植物附生细菌可能具有降解转化水体中双酚 A(BPA)能力从而影响该污染物在环境中的归趋.以轮叶黑藻为代表,分离筛选其BPA降解附生菌,结果共获得22株,在接种量为1×108个/mL,37℃下72h对BPA的去除率为11.46%~25.06%.选择降解率最高的3株细菌B12、B14和B23,采用16S rDNA鉴定,结合生理生化反应和形态观察,3株细菌分别为属于Lysinibacillus sp.(杆菌属),Brevibacterium sp.(短杆菌属)和Ochrobactrum sp.(苍白杆菌属).将3株菌株添加至轮叶黑藻无菌苗体系中,发现BPA去除率显著下降(P<0.05).物理去除部分野生轮叶黑藻表面部分附生细菌后,BPA去除率反而上升(约5%).综合本研究结果,沉水植物附生细菌具有降

  6. Eficácia do diquat no controle de Hydrilla verticillata, Egeria densa e Egeria najas e toxicidade aguda para o Guaru (Phallocerus caudimaculatus, em condições de laboratório Efficacy of diquat in the control of Hydrylla verticillata, Egeria densa and Egeria najas and its acute toxicity to Phallocerus caudimaculatus, under laboratory conditions

    Directory of Open Access Journals (Sweden)

    M.N.P. Henares

    2011-06-01

    Full Text Available No Brasil, as macrófitas aquáticas submersas, Egeria densa e Egeria najas, têm causado prejuízos aos usos múltiplos da água. Hydrilla verticillata foi recentemente introduzida, mas tem histórico como planta problemática nos EUA, no México e na Austrália. O objetivo deste trabalho foi avaliar as suscetibilidades relativas dessas três macrófitas aquáticas ao diquat e os riscos da utilização desse herbicida para o guaru (Phallocerus caudimaculatus. Para isso, foram instalados ensaios em condições de laboratório, a fim de avaliar a suscetibilidade relativa das três macrófitas por meio da manutenção de ponteiros dessas plantas em soluções contendo 0,0; 0,2; 0,4; 0,8; e 1,6 mg L-1 de diquat (Reward® por 14 dias. A avaliação foi realizada pela variação do acúmulo de matéria fresca e do comprimento dos ponteiros no período de exposição ao herbicida. H. verticillata mostrou maior sensibilidade ao diquat em comparação com as duas macrófitas do gênero Egeria, mesmo em baixas concentrações do herbicida. Nas maiores concentrações, E. densa mostrou maior sensibilidade que E. najas. O risco da aplicação do diquat para P. caudimaculatus foi estimado pela toxicidade aguda. Alevinos de P. caudimaculatus de 0,4 ± 0,2 mg foram expostos a soluções de 0,0; 1,0; 5,0; 10,0; 15,0; 20,0; 25,0; e 30,0 mg L-1 de diquat. A concentração letal de 50% (CL(I (50;96h do diquat estimada para P. caudimaculatus foi de 7,17 mg L-1. Para P. caudimaculatus, a toxicidade aguda foi superior à concentração recomendada para o controle de macrófitas aquáticas submersas, indicando risco muito baixo para esse peixe.In Brazil, the submerged plants Egeria densa and Egeria najas have caused damage to multiple uses of water. Hydrilla verticillata has been recently introduced, but it has a history as a problem plant in the U.S., Mexico and Australia. The objectives of this work were to assess the relative susceptibilities of these three

  7. Exploration for Natural Enemies of Hydrilla verticillata in Eastern Africa.

    Science.gov (United States)

    1980-05-01

    to Lake Baringo fol- lowed by Lake Naivasha bef6rb returning to Nairobi. Habitats Examined 25. The types of habitats surveyed were (a) rivers, (b... Lake Baringo , Baringo Silted and mud Typha sp. Province, Kenya brown from erosion Lake Naivasha, Photozone 1.5 m, mud Cyperus papyrus, Nakuru...consisted of two phasesi (a)a-vide survey through Tanzania and Kenya, followed by +*r’an intense survey of Lake Tanganyika, including a preliminary study

  8. Genetic Relationships among Invasive Hydrilla (Hydrilla verticillata L.f. Royle) Biotypes in the US and Their Implications for Management

    Science.gov (United States)

    2014-02-01

    1 US Army Engineer Research and Development Center, Vicksburg, MS. 2 Department of Biology , Texas Christian University, Fort Worth, TX. Report...2011). Experimental crosses have revealed that female dioecious plants in Florida are potentially fertile and can produce viable seed when pollinated by...Ecology Letters 13:145-153. Harms, N. E., Grodowitz, M. J. 2011. Overwintering biology of Hydrellia pakistanae, a biological control agent of

  9. Combining ALS-Inhibiting Herbicides with the Fungal Pathogen Mycoleptodiscus terrestris for Control of Hydrilla

    Science.gov (United States)

    2009-07-01

    response to adverse environmental conditions. In fermentation , microsclerotia that develop in the broth medium as nutrients, particularly carbon and...these cases, recovery rates may have been delayed. Thirdly, Mt can produce secondary inoculum in the form of spores. The exact timing of this event

  10. Competition Between Hydrilla verticillata and Vallisneria americana Under Different Environmental Conditions

    Science.gov (United States)

    1994-03-01

    interesting that this occurred only under the low fertility condition, since it has been suggested that foliar uptake and translocation of solution K to...ill. ; 28 cm. - (Technical report ; A-94-1 ) Includes bibliographic references. 1. Plant biomass. 2. Plant competition. 3. Fertilization of plants. I...of canopy-forming submersed aquatic plants, provide a habitat that is generally detrimental to fish and other desirable aquatic organisms (Newroth

  11. Aquatic Plant Control Research Program. Moneoecious hydrilla in the Potomac River.

    Science.gov (United States)

    1985-08-01

    omy 24:29-96. Pulich, W. M., Jr. 1982. Edaphic factors related to shoalgrass ( Halodule Wrightii Aschers.) production. Botanica Marina 25:467-475...dwelling organisms. The best available data concerning the benthic macroinvertebrate fauna of the freshwater tidal portion of the Potomac were...oxygenators in rivers. Water Research 2:243-248. Egglishaw, H. J. 1964. The distributional relationship between the bottom fauna and plant detritus in

  12. Induction of phytochelatins in hydrilla verticillata (l.f.) Royle under cadmium stress

    Energy Technology Data Exchange (ETDEWEB)

    Tripathi, R.D.; Rai, U.N.; Gupta, M. [National Botanical Research Institute, Lucknow (India)] [and others

    1996-03-01

    Plants tolerate Cd by sequestering them through synthesizing phytochelatins with the general structure (t-Glu-cys)n-gly where n= 2-11 depending upon the species from which these peptides are isolated. Recent biochemical evidence suggests that these peptides are synthesized via posttranslationally activated, metal-dependent enzymatic pathways from the precursor glutathione. However, most of these studies are confined to terrestrial species and only a few studies have been made on higher aquatic plants. Recently H. verticillata and other aquatic higher plants have been reported to be hyperaccumulators of Cd and have demonstrated the ability to remove many toxic metals, including Cd, from wastewater. It is hypothesized that cadmium hyperaccumulating ability of the macrophyte is associated with induction of the metal chelating peptides, the phytochelatins (PCs), to copeup with high cellular Cd levels. In view of this, it was considered worthwhile to examine the induction of phytochelatins and changes in levels of glutathione and related metabolites in H. verticillata under Cd stress.

  13. Biological and Host Range Studies with Bagous affinis, An Indian Weevil that Destroys Hydrilla Tubers. Aquatic Plant Control Research Program.

    Science.gov (United States)

    1994-12-01

    of Entomology and Nematology Institute of Food and Agriculture Services University of Florida Gainesville, FL 32606 Final report Approved for public...FL 32614-7100 Department of Entomology and Nematology , Institute of Food and Agriculture Services, University of Florida, Gainesville, FL 32606 9

  14. Molecular cytogenetic analysis of monoecious hemp (Cannabis sativa L.) cultivars reveals its karyotype variations and sex chromosomes constitution.

    Science.gov (United States)

    Razumova, Olga V; Alexandrov, Oleg S; Divashuk, Mikhail G; Sukhorada, Tatiana I; Karlov, Gennady I

    2016-05-01

    Hemp (Cannabis sativa L., 2n = 20) is a dioecious plant. Sex expression is controlled by an X-to-autosome balance system consisting of the heteromorphic sex chromosomes XY for males and XX for females. Genetically monoecious hemp offers several agronomic advantages compared to the dioecious cultivars that are widely used in hemp cultivation. The male or female origin of monoecious maternal plants is unknown. Additionally, the sex chromosome composition of monoecious hemp forms remains unknown. In this study, we examine the sex chromosome makeup in monoecious hemp using a cytogenetic approach. Eight monoecious and two dioecious cultivars were used. The DNA of 210 monoecious plants was used for PCR analysis with the male-associated markers MADC2 and SCAR323. All monoecious plants showed female amplification patterns. Fluorescence in situ hybridization (FISH) with the subtelomeric CS-1 probe to chromosomes plates and karyotyping revealed a lack of Y chromosome and presence of XX sex chromosomes in monoecious cultivars with the chromosome number 2n = 20. There was a high level of intra- and intercultivar karyotype variation detected. The results of this study can be used for further analysis of the genetic basis of sex expression in plants.

  15. The Ethylene Biosynthesis Gene CitACS4 Regulates Monoecy/Andromonoecy in Watermelon (Citrullus lanatus.

    Directory of Open Access Journals (Sweden)

    Susana Manzano

    Full Text Available Monoecious and andromonoecious cultivars of watermelon are characterised by the production of male and female flower or male and hermaphrodite flowers, respectively. The segregation analysis in the offspring of crosses between monoecious and andromonoecious lines has demonstrated that this trait is controlled by a single gene pair, being the monoecious allele M semi-dominant to the andromonoecious allele A. The two studied F1 hybrids (MA had a predominantly monoecious phenotype since both produced not only female flowers, but also bisexual flowers with incomplete stamens, and hermaphrodite flowers with pollen. Given that in other cucurbit species andromonoecy is conferred by mutations in the ethylene biosynthesis genes CmACS7, CsACS2 and CpACS27A we have cloned and characterised CitACS4, the watermelon gene showing the highest similarity with the formers. CitACS4 encoded for a type ACS type III enzyme that is predominantly expressed in pistillate flowers of watermelon. In the andromonoecious line we have detected a missense mutation in a very conserved residue of CitACS4 (C364W that cosegregates with the andromonoecious phenotype in two independent F2 populations, concomitantly with a reduction in ethylene production in the floral buds that will develop as hermaphrodite flowers. The gene does not however co-segregates with other sex expression traits regulated by ethylene in this species, including pistillate flowering transition and the number of pistillate flowers per plant. These data indicate that CitAC4 is likely to be involved in the biosynthesis of the ethylene required for stamen arrest during the development of female flowers. The C364W mutation would reduce the production of ethylene in pistillate floral buds, promoting the conversion of female into hermaphrodite flowers, and therefore of monoecy into andromonoecy.

  16. The Ethylene Biosynthesis Gene CitACS4 Regulates Monoecy/Andromonoecy in Watermelon (Citrullus lanatus).

    Science.gov (United States)

    Manzano, Susana; Aguado, Encarnación; Martínez, Cecilia; Megías, Zoraida; García, Alicia; Jamilena, Manuel

    2016-01-01

    Monoecious and andromonoecious cultivars of watermelon are characterised by the production of male and female flower or male and hermaphrodite flowers, respectively. The segregation analysis in the offspring of crosses between monoecious and andromonoecious lines has demonstrated that this trait is controlled by a single gene pair, being the monoecious allele M semi-dominant to the andromonoecious allele A. The two studied F1 hybrids (MA) had a predominantly monoecious phenotype since both produced not only female flowers, but also bisexual flowers with incomplete stamens, and hermaphrodite flowers with pollen. Given that in other cucurbit species andromonoecy is conferred by mutations in the ethylene biosynthesis genes CmACS7, CsACS2 and CpACS27A we have cloned and characterised CitACS4, the watermelon gene showing the highest similarity with the formers. CitACS4 encoded for a type ACS type III enzyme that is predominantly expressed in pistillate flowers of watermelon. In the andromonoecious line we have detected a missense mutation in a very conserved residue of CitACS4 (C364W) that cosegregates with the andromonoecious phenotype in two independent F2 populations, concomitantly with a reduction in ethylene production in the floral buds that will develop as hermaphrodite flowers. The gene does not however co-segregates with other sex expression traits regulated by ethylene in this species, including pistillate flowering transition and the number of pistillate flowers per plant. These data indicate that CitAC4 is likely to be involved in the biosynthesis of the ethylene required for stamen arrest during the development of female flowers. The C364W mutation would reduce the production of ethylene in pistillate floral buds, promoting the conversion of female into hermaphrodite flowers, and therefore of monoecy into andromonoecy.

  17. Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber

    Directory of Open Access Journals (Sweden)

    Margarida eRocheta

    2014-11-01

    Full Text Available Monoecious species provide a comprehensive system to study the developmental programs underlying the establishment of female and male organs in unisexual flowers. However, molecular resources for most monoecious non-model species are limited, hampering our ability to study the molecular mechanisms involved in flower development of these species. The objective of this study was to identify differentially expressed genes during the development of male and female flowers of the monoecious species Quercus suber, an economically important Mediterranean tree. Total RNA was extracted from different developmental stages of Q. suber flowers. Non-normalised cDNA libraries of male and female flowers were generated using 454 pyrosequencing technology producing a total of 962,172 high-quality reads with an average length of 264 nucleotides. The assembly of the reads resulted in 14,488 contigs for female libraries and 10,438 contigs for male libraries. Comparative analysis of the transcriptomes revealed genes differentially expressed in early and late stages of development of female and male flowers, some of which have been shown to be involved in pollen development, in ovule formation and in flower development of other species with a monoecious, dioecious or hermaphroditic sexual system. Moreover, we found differentially expressed genes that have not yet been characterised and others that have not been previously shown to be implicated in flower development. This transcriptomic analysis constitutes a major step towards the characterisation of the molecular mechanisms involved in flower development in a monoecious tree with a potential contribution towards the knowledge of conserved developmental mechanisms in other species.

  18. Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber.

    Science.gov (United States)

    Rocheta, Margarida; Sobral, Rómulo; Magalhães, Joana; Amorim, Maria I; Ribeiro, Teresa; Pinheiro, Miguel; Egas, Conceição; Morais-Cecílio, Leonor; Costa, Maria M R

    2014-01-01

    Monoecious species provide a comprehensive system to study the developmental programs underlying the establishment of female and male organs in unisexual flowers. However, molecular resources for most monoecious non-model species are limited, hampering our ability to study the molecular mechanisms involved in flower development of these species. The objective of this study was to identify differentially expressed genes during the development of male and female flowers of the monoecious species Quercus suber, an economically important Mediterranean tree. Total RNA was extracted from different developmental stages of Q. suber flowers. Non-normalized cDNA libraries of male and female flowers were generated using 454 pyrosequencing technology producing a total of 962,172 high-quality reads with an average length of 264 nucleotides. The assembly of the reads resulted in 14,488 contigs for female libraries and 10,438 contigs for male libraries. Comparative analysis of the transcriptomes revealed genes differentially expressed in early and late stages of development of female and male flowers, some of which have been shown to be involved in pollen development, in ovule formation and in flower development of other species with a monoecious, dioecious, or hermaphroditic sexual system. Moreover, we found differentially expressed genes that have not yet been characterized and others that have not been previously shown to be implicated in flower development. This transcriptomic analysis constitutes a major step toward the characterization of the molecular mechanisms involved in flower development in a monoecious tree with a potential contribution toward the knowledge of conserved developmental mechanisms in other species.

  19. U.S. Department of Agriculture/Corps of Engineers Cooperative Aquatic Plant Control Research. Annual Report for FY 1981. Biological and Chemical Control Technologies.

    Science.gov (United States)

    1983-10-01

    aed" the Melt s lraefed voraciously on alligatorweed 16 Mandalay , Burma (14-15 July) In the Mandalay -Sagaing area I searched for hydrilla and...hydrilla is not present in flooded areas. There are patches of hydrilla in the moat surrounding Mandalay Fort. This hydrilla also shows little...pressure. The most common aquatic plant in Mandalay Moat is coontail, Ceratophyllum sp. Bangkok, Thailand (16-22 July) In Bangkok I discussed project goals

  20. Expanded Simulation Models "Version 3.0" for Growth of the Submerged Aquatic Plants American Wildcelery, Sago Pondweed, Hydrilla, and Eurasian Watermilfoil

    Science.gov (United States)

    2007-11-01

    descriptions of the vegetation responses to daily changes in current velocity and epiphyte shading, and accommodation of daily changes in water level...in current velocity, and epiphyte shading, or to combinations of factors. Once the vegetation is lost from a given locale, increased sediment...responses to changes in current velocity and light attenuation by epiphytes and allow only annual changes in water level. These versions are available

  1. Identification and bioinformatics comparison of two novel phosphatases in monoecious and gynoecious cucumber lines

    Science.gov (United States)

    Pawełkowicz, Magdalena E.; Wojcieszek, Michał; Osipowski, Paweł; Krzywkowski, Tomasz; PlÄ der, Wojciech; Przybecki, Zbigniew

    2016-09-01

    Two Arabidopsis thaliana genes from the PP2C family of protein phosphatases (AtABI1 and AtABI2) were used to find orthologous genes in the Cucumis sativus L. cv. Borszczagowski (cucumber) genome. Cucumber has been used as a model plant for sex expression studies because although it has been defined as a monoecious species, numerous genotypes are known to produce only female, only male, or hermaphroditic flowers. We identified two new orthologous genes of AtABI1 and AtABI2 in the cucumber genome and named them CsABI1 and CsABI2. To determine the relationships between the regulation of CsABI1 and CsABI2 and flower morphogenesis in cucumber, we performed various computational analyses to define the structure of the genes, and to predict regulatory elements and protein motifs in their sequences. We also performed an expression analysis to identify differences in the expression levels of CsABI1 and CsABI2 in vegetative and generative tissues (leaf, shoot apex, and flower buds) of monoecious (B10) and gynoecious (2gg) cucumber lines. We found that the expressions of CsABI1 and CsABI2 differed in male and female floral buds, and correlated these findings with the abscisic acid signaling pathways in male and female flowers.

  2. Hormonal interactions and gene regulation can link monoecy and environmental plasticity to the evolution of dioecy in plants.

    Science.gov (United States)

    Golenberg, Edward M; West, Nicholas W

    2013-06-01

    Most models for dioecy in flowering plants assume that dioecy arises directly from hermaphroditism through a series of independent feminizing and masculinizing mutations that become chromosomally linked. However, dioecy appears to evolve most frequently through monoecious grades. The major genetic models do not explain the evolution of unisexual flowers in monoecious and submonoecious populations, nor do they account for environmentally induced sexual plasticity. In this review, we explore the roles of environmental stress and hormones on sex determination, and propose a model that can explain the evolution of dioecy through monoecy, and the mechanisms of environmental sex determination. Environmental stresses elicit hormones that allow plants to mediate the negative effects of the stresses. Many of these same hormones are involved in the regulation of floral developmental genes. Recent studies have elucidated the mechanisms whereby these hormones interact and can act as switchpoints in regulatory pathways. Consequently, differential concentrations of plant hormones can regulate whole developmental pathways, providing a mechanism for differential development within isogenic individuals such as seen in monoecious plants. Sex-determining genes in such systems will evolve to generate clusters of coexpressed suites. Coexpression rather than coinheritance of gender-specific genes will define the sexual developmental fate. Therefore, selection for gender type will drive evolution of the regulatory sequences of such genes rather than their synteny. Subsequent mutations to hyper- or hyposensitive alleles within the hormone response pathway can result in segregating dioecious populations. Simultaneously, such developmental systems will remain sensitive to external stimuli that modify hormone responses.

  3. Transmission of herbicide resistance from a monoecious to a dioecious weedy Amaranthus species.

    Science.gov (United States)

    Tranel, J.; Wassom, J.; Jeschke, R.; Rayburn, L.

    2002-10-01

    The genus Amaranthus includes several important monoecious and dioecious weed species, and several populations of these species have developed resistance to herbicides. These species are closely related and two or more species often coexist in agricultural settings. Collectively, these attributes raise the concern that herbicide resistance might transfer from one weedy Amaranthus species to another. We performed research to determine if a dominant allele encoding a herbicide-insensitive form of acetolactate synthase (ALS) could be transferred from a monoecious species, A. hybridus, to a dioecious species, A. rudis. Numerous F(1) hybrids were obtained from controlled crosses in a greenhouse between A. rudis and herbicide-resistant A. hybridus, and most (85%) of these hybrids were herbicide-resistant. Molecular analysis of the ALS gene was used to verify that herbicide-resistant hybrids contained both an A. rudis and an A. hybridus ALS allele. Although hybrids had greatly reduced fertility, 42 BC(1) plants were obtained by backcrossing 33 hybrids with male A. rudis. Fertility was greatly restored in BC(1) progeny, and numerous BC(2) progeny were obtained from a second backcross to A. rudis. The herbicide-resistance allele from A. hybridus was transmitted to 50% of the BC(1) progeny. The resistance allele was subsequently transmitted to and conferred herbicide resistance in 39 of 110 plants analyzed from four BC(2) families. Parental species, hybrids, and BC(2) progeny were compared for 2C nuclear DNA contents. The mean hybrid 2C nuclear DNA content, 1.27 pg, was equal to the average between A. rudis and A. hybridus, which had 2C DNA contents of 1.42 and 1.12 pg, respectively. The mean 2C DNA content of BC(2) plants, 1.40 pg, was significantly (alpha herbicide resistance can be acquired by A. rudis through a hybridization event with A. hybridus.

  4. Comparative Transcriptome Analysis between Gynoecious and Monoecious Plants Identifies Regulatory Networks Controlling Sex Determination in Jatropha curcas.

    Science.gov (United States)

    Chen, Mao-Sheng; Pan, Bang-Zhen; Fu, Qiantang; Tao, Yan-Bin; Martínez-Herrera, Jorge; Niu, Longjian; Ni, Jun; Dong, Yuling; Zhao, Mei-Li; Xu, Zeng-Fu

    2016-01-01

    Most germplasms of the biofuel plant Jatropha curcas are monoecious. A gynoecious genotype of J. curcas was found, whose male flowers are aborted at early stage of inflorescence development. To investigate the regulatory mechanism of transition from monoecious to gynoecious plants, a comparative transcriptome analysis between gynoecious and monoecious inflorescences were performed. A total of 3,749 genes differentially expressed in two developmental stages of inflorescences were identified. Among them, 32 genes were involved in floral development, and 70 in phytohormone biosynthesis and signaling pathways. Six genes homologous to KNOTTED1-LIKE HOMEOBOX GENE 6 (KNAT6), MYC2, SHI-RELATED SEQUENCE 5 (SRS5), SHORT VEGETATIVE PHASE (SVP), TERMINAL FLOWER 1 (TFL1), and TASSELSEED2 (TS2), which control floral development, were considered as candidate regulators that may be involved in sex differentiation in J. curcas. Abscisic acid, auxin, gibberellin, and jasmonate biosynthesis were lower, whereas cytokinin biosynthesis was higher in gynoecious than that in monoecious inflorescences. Moreover, the exogenous application of gibberellic acid (GA3) promoted perianth development in male flowers and partly prevented pistil development in female flowers to generate neutral flowers in gynoecious inflorescences. The arrest of stamen primordium at early development stage probably causes the abortion of male flowers to generate gynoecious individuals. These results suggest that some floral development genes and phytohormone signaling pathways orchestrate the process of sex determination in J. curcas. Our study provides a basic framework for the regulation networks of sex determination in J. curcas and will be helpful for elucidating the evolution of the plant reproductive system.

  5. Living on the edge: Fig tree phenology at the northern range limit of monoecious Ficus in China

    Science.gov (United States)

    Zhang, Lu-Shui; Compton, Stephen G.; Xiao, Hui; Lu, Qian; Chen, Yan

    2014-05-01

    Fig trees (Ficus) are a species-rich group of mainly tropical and subtropical plants that are of ecological importance because of the large numbers of vertebrates that utilise their figs for food. Factors limiting their distributions to warmer regions are still poorly understood, but are likely to include factors linked to their specialised pollination biology, because each Ficus species is dependent on one or a small number of host-specific fig wasps (Agaonidae) for pollination. Adult fig wasps are short-lived, but some species are capable of dispersing extremely long distances to pollinate their hosts. Close to its northern range limit we investigated the phenology of Ficus virens, the monoecious fig tree that reaches furthest north in China. Relatively few trees produced any figs, and very few retained figs throughout the winter. Despite this, new crops produced in spring were pollinated, with seasonally migrant pollinators from plants growing further south the most likely pollen vectors. An inability to initiate new crops at low temperatures may limit the distribution of monoecious fig trees to warmer areas.

  6. Acclimation to high CO/sub 2/ in monoecious cucumbers. I. Vegetative and reproductive growth. [Cucmuis sativus L

    Energy Technology Data Exchange (ETDEWEB)

    Peet, M.M.

    1986-01-01

    CO/sub 2/ concentrations of 1000 compared to 350 microliters per liter in controlled environment chambers did not increase total fruit weight or number in a monoecious cucumber (Cucumis sativus L. cv Chipper) nor did it increase biomass, leaf area, or relative growth rates beyond the first 16 days after seeding. Average fruit weight was slightly, but not significantly greater in the 1000 microliters per liter CO/sub 2/ treatment because fruit numbers were changed more than total weight. Plants grown at 1000 and 350 microliters per liter CO/sub 2/ were similar in distribution of dry matter and leaf area between mainstem, axillary, and subaxillary branches. Early flower production was greater in 1000 microliters per liter plants. Subsequent flower numbers were either lower in enriched plants or similar in the two treatments, except for the harvest at fruiting when enriched plants produced many more male flowers than the 350 microliters per liter treatments.

  7. Preliminary Testing of Mycoleptodiscus terrestris Formulations

    Science.gov (United States)

    2009-03-01

    submersed macrophyte , Hydrilla verticillata (L.f.) Royle (hydrilla). BACKGROUND: As herbicide resistance becomes an increasing problem worldwide...Mycoleptodiscus terrestris, as a biocontrol agent for the management of Myriophyllum spicatum in Lake Guntersville Reservoir . Technical Report A-96-4

  8. Ecological Effects of Exotic and Native Aquatic Vegetation

    Science.gov (United States)

    2009-08-01

    ponds (α=0.05). ..............................................72 Figure 58. Odonata (dragonflies and damselflies) counts were highest in hydrilla ponds...Anax Odonata Dragonflies & damselflies Baetidae Callibaetis Ephemeroptera Mayflies Caenidae Caenis Notonectidae Buenoa Belastomatidae...nificantly smaller and in poorer condition in the latter. Numbers of ERDC/EL TR-09-10 74 bluegills were low in hydrilla ponds. Odonata November Pond

  9. Using Remote Sensing and Spatial Information Technologies to Detect and Map Two Aquatic Macrophytes

    OpenAIRE

    Everitt, J.H.; Yang, C.; Escobar, D.E.; Webster, C.F.; Lonard, R.I.; Davis, M.R.

    1999-01-01

    This paper describes the light reflectance characteristics ofwaterhyacinth [Eichhornia crassipes (Mort.) Solms] and hydrilla [Hydrilla verticillata (L.F.) Royle] and the application of airborned videography with global positioning system (GPS) and geographic information system (GIS) technologies for distinguishing and mapping the distribution of these two aquatic weeds in waterways of southern Texas. Field reflectance measurements made at several locations showed that waterhyacinth generall...

  10. A three-genome phylogeny of Momordica (Cucurbitaceae) suggests seven returns from dioecy to monoecy and recent long-distance dispersal to Asia.

    Science.gov (United States)

    Schaefer, Hanno; Renner, Susanne S

    2010-02-01

    The bitter gourd genus Momordica comprises 47 species in Africa and 12 in Asia and Australia. All have unisexual flowers, and of the African species, 24 are dioecious, 23 monoecious, while all Asian species are dioecious. Maximum likelihood analyses of 6257 aligned nucleotides of plastid, mitochondrial and nuclear DNA obtained for 122 accessions of Momordica and seven outgroups show that Momordica is monophyletic and consists of 11 well-supported clades. Monoecy evolved from dioecy seven times independently, always in Africa and mostly in savanna species with low population densities. Leaky dioecy, with occasional fruit-producing males, occurs in two African species and might be the first step in an evolutionary transition towards monoecy. Dated biogeographic analyses suggest that Momordica originated in tropical Africa and that the Asian species are the result of one long-distance dispersal event about 19million years ago. The pantropical vegetable Momordica charantia is of African, not Asian origin as had previously been suggested. Copyright (c) 2009 Elsevier Inc. All rights reserved.

  11. Estimating seed and pollen movement in a monoecious plant: a hierarchical Bayesian approach integrating genetic and ecological data.

    Science.gov (United States)

    Moran, Emily V; Clark, James S

    2011-03-01

    The scale of seed and pollen movement in plants has a critical influence on population dynamics and interspecific interactions, as well as on their capacity to respond to environmental change through migration or local adaptation. However, dispersal can be challenging to quantify. Here, we present a Bayesian model that integrates genetic and ecological data to simultaneously estimate effective seed and pollen dispersal parameters and the parentage of sampled seedlings. This model is the first developed for monoecious plants that accounts for genotyping error and treats dispersal from within and beyond a plot in a fully consistent manner. The flexible Bayesian framework allows the incorporation of a variety of ecological variables, including individual variation in seed production, as well as multiple sources of uncertainty. We illustrate the method using data from a mixed population of red oak (Quercus rubra, Q. velutina, Q. falcata) in the NC piedmont. For simulated test data sets, the model successfully recovered the simulated dispersal parameters and pedigrees. Pollen dispersal in the example population was extensive, with an average father-mother distance of 178 m. Estimated seed dispersal distances at the piedmont site were substantially longer than previous estimates based on seed-trap data (average 128 m vs. 9.3 m), suggesting that, under some circumstances, oaks may be less dispersal-limited than is commonly thought, with a greater potential for range shifts in response to climate change.

  12. De Novo Assembly of Bitter Gourd Transcriptomes: Gene Expression and Sequence Variations in Gynoecious and Monoecious Lines.

    Science.gov (United States)

    Shukla, Anjali; Singh, V K; Bharadwaj, D R; Kumar, Rajesh; Rai, Ashutosh; Rai, A K; Mugasimangalam, Raja; Parameswaran, Sriram; Singh, Major; Naik, P S

    2015-01-01

    Bitter gourd (Momordica charantia L.) is a nutritious vegetable crop of Asian origin, used as a medicinal herb in Indian and Chinese traditional medicine. Molecular breeding in bitter gourd is in its infancy, due to limited molecular resources, particularly on functional markers for traits such as gynoecy. We performed de novo transcriptome sequencing of bitter gourd using Illumina next-generation sequencer, from root, flower buds, stem and leaf samples of gynoecious line (Gy323) and a monoecious line (DRAR1). A total of 65,540 transcripts for Gy323 and 61,490 for DRAR1 were obtained. Comparisons revealed SNP and SSR variations between these lines and, identification of gene classes. Based on available transcripts we identified 80 WRKY transcription factors, several reported in responses to biotic and abiotic stresses; 56 ARF genes which play a pivotal role in auxin-regulated gene expression and development. The data presented will be useful in both functions studies and breeding programs in bitter gourd.

  13. Biological Control of Aquatic Plants with Pathogenic Fungi

    Science.gov (United States)

    1981-01-01

    been found thus far in nature or under arti- ficial treatments of uredia- bearing leaves of waterhyacinth in labora- tory. In the absence of knowledge...of these bacteria on healthy hydrilla. D5 Table DI Description of Seven Isolated Bacteria Grown on NA Plates Isolate 1 White, gummy , some slime...6 White, very slow growth, myceloid 7 Pink, some slime, gummy , slow growth, myceloid Table D2 Visual Comparison of Hydrilla Sprigs Three Weeks After

  14. Final Environmental Assessment: For the M270 Multiple Launch Rocket System (MLRS) Expanded Training Use Areas at Avon Park Air Force Range, Florida

    Science.gov (United States)

    2005-11-10

    panther Puma concolor coryi E E Florida black bear Ursus americanus floridans N T Reptiles and Amphibians Eastern indigo snake Drymarchon corais...hyacinth Eugenia uniflora Surinam cherry Hydrilla verticillata Hydrilla Hymenachne amplexicaulis West Indian marsh grass Imperata cylindrica Cogon grass...garnoti) are some amphibian and reptile species that occur within the built up areas of APAFR (U.S. Navy, 2004). Sub-tropical bird species noted to

  15. Patterns and sources of variation in pollen deposition and pollen tube formation in flowers of the endemic monoecious shrub Cnidoscolus souzae (Euphorbiaceae).

    Science.gov (United States)

    Arceo-Gómez, G; Alonso, C; Abdala-Roberts, L; Parra-Tabla, V

    2016-07-01

    Pollen deposition and pollen tube formation are key components of angiosperm reproduction but intraspecific variation in these has rarely been quantified. Documenting and partitioning (populations, plants and flowers) natural variation in these two aspects of plant reproduction can help uncover spatial mosaics of reproductive success and underlying causes. In this study, we assess variation in pollen deposition and pollen tube formation for the endemic monoecious shrub Cnidoscolus souzae throughout its distribution range in Mexico, and determine how this variation is structured among populations, plants and flowers. We also infer the relative importance of pollen quantity and quality in determining pollination success in this species. While we found no evidence suggesting that pollen receipt limits C. souzae reproduction across 19 populations, we did find extensive variation in pollen load size and pollen tube number per flower. Total variation in pollen receipt and pollen tube number was mostly explained by intra-individual and among-population variance. Furthermore, pollen load size had a stronger effect on the number of pollen tubes at the base of the style than pollen germination rate, suggesting that pollen quantity may be more important than quality for pollen tube success in C. souzae. Our results suggest that both small within-plant flower differences and broad-scale differences in community attributes can play an important role in determining pollination success. We emphasise the need to evaluate patterns and sources of variation in pollen deposition and pollen tube formation as a first step in understanding the causes of variation in pollination success over broad spatial scales.

  16. Temporal trends and effects of diversity on occurrence of exotic macrophytes in a large reservoir

    Science.gov (United States)

    Thomaz, Sidinei Magela; Carvalho, Priscilla; Mormul, Roger Paulo; Ferreira, Fernando Alves; Silveira, Márcio José; Michelan, Thaísa Sala

    2009-09-01

    Two exotic invasive macrophyte species (the emergent Urochloa subquadripara - tenner-grass - and the submersed Hydrilla verticillata - hydrilla) were investigated in a large sub-tropical reservoir. We analyzed their occurrences over an extended period and tested the hypothesis that macrophyte richness decreases their invasibility. The alternative hypothesis that the occurrence of these exotics is affected by fetch and underwater radiation (important determinants of macrophyte assemblage composition in this reservoir) was also tested. Incidence data (presence/absence) was obtained over 9.5 years at 235 stations. Logistic regression was applied to test whether the likelihood of occurrence of these two species was affected by macrophyte richness, fetch or underwater radiation. Tenner-grass was recorded at a high frequency and quickly recovered from disturbances caused by water drawdown. In contrast, H. verticillata was first recorded in 3 sites in January 2007, but it spread quickly, reaching 30.5% of the sites 19 months later. The main channel of the Paraná River was the main source of propagules for this species. The likelihood of occurrence of tenner-grass was positively affected by macrophyte richness but negatively affected by fetch. Thus, wave disturbance is probably more important than diversity in preventing invasion by this species. Hydrilla, by contrast, was negatively affected by macrophyte richness and positively affected by fetch and underwater radiation. Although this result might indicate that macrophyte diversity prevents hydrilla invasion, this is probably not true because hydrilla colonized deeper sites where few species of plant exist. Resistance to disturbances caused by water drawdown (tenner-grass) and waves (hydrilla) as well as persistency of tenner-grass and fast spread of hydrilla make these exotic species a cause for concern because of their potential impacts on water uses and maintenance of diversity.

  17. Evaluation of butachlor for control of some submerged macrophytes along with its impact on biotic components of freshwater system

    Directory of Open Access Journals (Sweden)

    A. Chattopadhyay, S. Adhikari, S. P. Adhikary, S. Ayyappan

    2006-04-01

    Full Text Available In this investigation, the efficacy of the herbicide butachlor, (N-butoxymethyl-2 chloro-21, 61 diethyl acetanilide was tested against few common submerged macrophytes namely Hydrilla (Hydrilla verticillata (L. Royale, Najas (Najas minor All., Nechamandra (Nechamandra alternifolia (Roxb. Thwaites and Ottelia (Ottelia alismoides (L. Pers. of freshwater fish ponds. Almost complete decay of Hydrilla, Nechamandra and Ottelia was achieved at 7.5 L of active ingredient/ha/m butachlor within 15 days while the herbicide showed no negative effect on Najas. However at the same concentration of butachlor, total mortality of zooplankton and water fern Azolla (Azolla caroliniana Lamarck occurred within seven days. In case of few freshwater fish species like Rohu (Labeo rohita, Channa (Channa punctatus, Anabas (Anabas testitudineus and Heteropneustes (Heteropneustes fossilis, total mortality occurred upto 90 days after application of the same dose of butachlor but fish survived beyond 120 days of herbicide application indicating degradation of the herbicides.

  18. 水生植物的生态敏感度研究%Ecological Sensitivity of Aquatic Plants

    Institute of Scientific and Technical Information of China (English)

    李宏文; Paul; K.Chien

    2001-01-01

    Throughy the study on the ecological effects of Cd and Zn onseveral aquatic plants,the ecological sensitivity of 5 species is determined.The results show that according to critical time when plants are injured by Cd and Zn,the order for ecological sensitivity of 5 species is:Nymphoides peltatum>Hydrilla verticillata>Potamogeton malaianus>Spirodela polyrhiza>Alternanthera philoxeroides.The results also show that on basis of catalase activity of aquatic plants,the order for ecological sensitivity of 5 species is:Alternanthera philoxeroides>Spirodela polyrhiza≈Potamogeton malaianus>Hydrilla verticillata>Nymphoides peltatum.It is evident that the pollution-durablty Potamogeton malaianus is higher than for Nymphoides peltatum and Hydrilla verticillata,pollution-sensible species

  19. Monoecy, anemophily, anemochory and regeneration ecology of Hildegardia populifolia (Roxb. Schott. and Endl. (Malvaceae, an economically important endemic and endangered dry deciduous tree species of southern Eastern Ghats, India

    Directory of Open Access Journals (Sweden)

    A.J.S. Raju

    2014-02-01

    Full Text Available Hildegardia populifolia is a critically endangered tree species. All phenological events—leaf flushing, shedding, flowering, fruit dispersal occur one after the other during the dry season. It is morphologically andromonoecious but functionally monoecious. It produces a strikingly male-biased male and bisexual flower ratio; it is self-incompatible and obligately outcrossing. The flowers are nectariferous and the nectar has hexose-rich sugars, some essential and non-essential amino acids. Trigona bee and Rhynchium wasp were the exclusive foragers, though their foraging activity does not promote cross-pollination. The male flower number, the pollen output, the pollen characteristics and the placement of anthers on the top of androphore conform to anemophily. The natural fruit set does not exceed 5%. The fruit is 5-follicled with one or two seeds. The low fruit set is compensated by the production of more 2-seeded follicles. Fruit characteristics such as wing-like follicles, membranous follicle sheath and being very light weight characterize anemochory. Seeds with a hard coat do not germinate readily during the rainy season and their germination depends on the soil chemicals and nutrient environment. The soil is deficient in nitrogen, potassium and phosphorous. Partly burned seeds due to natural or human-caused fires germinate quickly in water saturated soil. The study suggests that seed germination and seedling growth rates are regulated by intrinsic and extrinsic factors along with natural and anthropogenic fires. We recommend that seedlings should be raised in nurseries and then transferred to natural habitats to build up the population.

  20. Elodea canadensis under N and CO2 limitation : Adaptive changes in Rubisco and PEPCase activity in a bicarbonate user

    NARCIS (Netherlands)

    Van Ginkel, LC; Schutz, [No Value; Prins, HBA

    2000-01-01

    Diffusion of CO2 in water is 10,000 times slower than in air. Because of this photosynthesis in submerged aquatic macrophytes is often limited by CO2 availability. Elodea canadensis shows HCO3- utilization under conditions of CO2 limitation. A closely related species, Hydrilla verticillata, which al

  1. Bioassay of Plant Growth Regulator Activity on Aquatic Plants

    Science.gov (United States)

    1990-07-01

    found at 7.5 pg 2 (data not shown). Presumed toxic effects such as brittleness and an increased red pigmentation kpresumably anthocyanins ) £-I were...more than 50 percent over untreated controls (Table 1). As described above, these hydrilla segments were red in color , and it was apparent that they

  2. Introduced aquatic plants and algae

    Science.gov (United States)

    Non-native aquatic plants such as waterhyacinth and hydrilla severely impair the uses of aquatic resources including recreational faculties (lakes, reservoirs, rivers) as well as timely delivery of irrigation water for agriculture. Costs associated with impacts and management of all types of aquatic...

  3. Aquatic Plant Control Research Program. Effects of Organic Amendments to Sediment on Freshwater Macrophyte Growth.

    Science.gov (United States)

    1983-10-01

    The growth of three submersed macrophyte species (Myriophyllum spicatum, Hyjdri11a verticillata, and Elodea canadensis) and three partially emergent... Elodea canadensis Rich. in Michx; and Hydrilla verticillata (L.f.) Caspary. Nomenclature follows Godfrey and Wooten (1979, 1981). The first two species

  4. Final Environmental Assessment for the Installation of a Range Safety Lighting System at Avon Park Air Force Range, Florida

    Science.gov (United States)

    2010-08-01

    Sterna antillarum N T Mammals Florida panther Puma concolor coryi E E Florida black bear Ursus americanus floridans N T Reptiles and Amphibians ...Casuarina glauca Australian pine Dioscorea bulbifera Air potato Eichhornia crassipes Water hyacinth Eugenia uniflora Surinam cherry Hydrilla...Cuban treefrog (Osteophilus septentrionalis), Cuban brown anole (Anole sagrei) and the Indo-Pacific gecko (Hemidactylus garnoti) are some amphibian and

  5. Reproductive biology in monoecious and gynoecious cucumber cultivars as a result of IBA application Biologia reprodutiva de cultivares monóicas e ginóicas de pepino em função do uso de AIB

    Directory of Open Access Journals (Sweden)

    Valdir Diola

    2008-03-01

    Full Text Available The understanding of both the reproductive biology and the regulation of the sexual expression of cucumber flowers (Cucumis sativus makes crop management easier and can improve fruit yield and quality. The objective of this study was to evaluate the physiological answer of cucumber floral verticils to the application of IBA. The experiment was carried out in a greenhouse, in completely randomized blocks, with four replications of 4-plant plots, and treatments applied to a 5 x 2 factorial (0, 50, 100, 200, and 500 µmol of IBA, and two cultivars: Wisconsin MR28, gynoecious, and Caipira, monoecious. Cultivar Wisconsin MR28 produced in average 7,636 pollen grains (PG per flower, with a positive linear response to the increase in IBA concentration. Instead, in cultivar Caipira (5,160 PG all IBA concentrations reduced PG production. Cultivars did not differ from each other in relation to PG viability (average in vitrogermination of 75.4 and 79.9% to cultivars Wisconsin MR28 and Caipira, respectively and in both PG viability increased linearly with the increase in AIB concentration. Cultivars Wisconsin MR28 and Caipira presented in average 71.6 and 70.6 seeds per fruit respectively, and responded with an increase in seed number and improvement in fruit general aspect to the rise in IBA concentration. The ratio male:female flowers was significantly different between cultivars (4.2:1 and 3.5:1, respectively to cultivars Wisconsin MR28 and Caipira and responded in a distinct way to IBA concentrations. While in cultivar Caipira, IBA concentrations near to 100 µmol increased the number of male flowers; in cultivar Wisconsin MR28 the same IBA concentration reduced it. The two cultivars had a similar number of female flowers. However, whereas it remained relatively stable in cultivar Caipira in spite of the increase in IBA concentration, there was an increase in the number of female flowers in cultivar Wisconsin MR28, as a result of the rise in IBA

  6. Monitoring Invasive Aquatic Vegetation in Lake Okeechobee, Florida, Using NDVI Derived from Modis Data

    Science.gov (United States)

    Woods, Kate; Brozen, Madeline; Malik, Sadaf; Maki, Angela

    2009-01-01

    Lake Okeechobee, located in southern Florida, encompasses approximately 1,700 sq km and is a vital part of the Lake Okeechobee and Everglades ecosystem. Major cyanobacterial blooms have been documented in Lake Okeechobee since the 1970s and have continued to plague the ecosystem. Similarly, hydrilla, water hyacinth, and water lettuce have been documented in the lake and continue to threaten the ecosystem by their rapid growth. This study examines invasive aquatic vegetation occurrence through the use of the Normalized Difference Vegetation Index (NDVI) calculated on MOD09 surface reflectance imagery. Occurrence during 2008 was analyzed using the Time Series Product Tool (TSPT), a MATLAB-based program developed at John C. Stennis Space Center. This project tracked spatial and temporal variability of cyanobacterial blooms, and overgrowth of water lettuce, water hyacinth, and hydrilla. In addition, this study presents an application of Moderate Resolution Imaging Spectroradiometer (MODIS) data to assist in water quality management.

  7. Environmental Factors Influencing Blooms of a Neurotoxic Stigonematalan Cyanobacterium Responsible for Avian Vacuolar Myelinopathy

    Science.gov (United States)

    2013-01-01

    killing waterbirds and raptors , to an epiphytic cyanobacterium which grows primarily on nonindigenous submerged aquatic vegetation (SAV). Water- birds...intramyelinic edema, in the organisms’ CNS tissue, most commonly the brain (Thomas et al. 1998). AVM-afflicted birds display erratic behavior ; clinical symptoms... feeding trials. Gavage trials with a methanol extract of the hydrilla-UCB demonstrated that extract would cause clinical symptoms and AVM lesions in

  8. Point Intercept and Surface Observation GPS (SOG): A Comparison of Survey Methods - Lake Gaston, NC/VA

    Science.gov (United States)

    2008-11-01

    coverage by hydrilla was greater than 50% (littoral zone approximately 5,000 acres, Madsen 2007). Scientific name Common name Exotic/native Whole lake...vegetation in the lake. Scientific name Common name Monospecific acres Total acres Native emergent Echinodorus cordifolius creeping burhead...0.001 0.001 Eleocharis macrostachya flatstem spikerush 0.002 0.002 E. quadrangulata squarestem spikerush 2.66 7.21 Hibiscus spp. mallow 0.06 0.27

  9. Apparent Herbivory and Indigenous Pathogens of Invasive Flowering Rush (Butomus umbellatus L.) in the Pacific Northwest

    Science.gov (United States)

    2015-06-01

    hand or with a garden trowel. Though flowering rush spreads vegetatively and produces extensive underground rhizome systems, for the purposes of this...the Great Smoky Mountains National Park in 2004 (Baird et al. 2007). Both F. oxysporum and Phoma have broad host ranges, which may limit their...is dubious, considering that the majority of them have been tested on other plant species (hydrilla and Eurasian watermilfoil) with little success

  10. Incidence and Management Costs of Freshwater Aquatic Nuisance Species at Projects Operated by the U.S. Army Corps of Engineers

    Science.gov (United States)

    2010-07-01

    the occurrence of ANS impacts (Yes or No) from freshwater algae, large aquatic plants, fish , zebra mussels, Asiatic clams, water fleas, crayfish...investment in research and development, especially for nuisance aquatic plants, fresh- water clams, and certain invasive fish species. Even so, aggregate...water hyacinths, hydrilla, common reed, sea lamprey, and the zebra mussel are especially notorious for their costly impacts on freshwater services

  11. Field and laboratory evaluation of the influence of copper-diquat on apple snails in southern Florida

    Science.gov (United States)

    Winger, P.V.; Imlay, M.J.; McMillan, W.E.; Martin, T.W.; Takekawa, Jean E.; Johnson, W.W.

    1984-01-01

    The recent decline of apple snail (Pomacea paludosa) populations in canals surrounding Loxahatchee National Wildlife Refuge in southern Florida coincided with the use of copper-diquat for the control of the aquatic weed hydrilla (Hydrilla verticillata). Field and laboratory studies were designed to assess the effects of copper-diquat on apple snails, which are the primary food of the endangered snail kite Rostrhamus sociabilis (formerly known as the Everglade kite). Acute toxicities (96-h LC50 values) of Cutrine-Plus and Komeen (chelated formulations of copper) to immature apple snails were 22 and 24 μg/L, respectively. Diquat was toxic at a concentration of 1,800 μg/L and did not increase the toxicity of copper when the chemicals were used in combination. Evaluation of field samples indicated that copper concentrations were higher in detritus than in water, plants and mud, and that there was a gradient of copper concentration from the canal to the interior, the highest residues being in samples from the canal. Copper associated with detritus (up to 150 μg/g) had no effect on growth or survival of apple snails in field cage and tank studies. Also, field applications of copper-diquat to hydrilla had no effect on survival of caged adult and immature snails. Copper from field applications was rapidly taken out of solution by plants and organic material in the water and subsequently incorporated into the bottom detritus. Although the effects of repeated applications of copper-diquat and high body burdens of copper (accumulated during exposure to herbicidal treatment) on survival and reproduction of apple snails are not known, the information available indicates that treatment of hydrilla with copper-diquat was probably not responsible for the decline in the apple snail population. Application at recommended rates should pose no threat to these snails in the organically rich waters of southern Florida.

  12. 伊乐藻的利用价值

    Institute of Scientific and Technical Information of China (English)

    杨清心

    1988-01-01

    伊乐藻(Elodea nuttallii)原产美洲,是一种速生高产的沉水高等植物,与我国淡水水域中分布的黑藻(Hydrilla verticilata)苦草(Vallisneria spiralis)同属水鳖科(Hydrocharitaceae),是草食性鱼类的优良饲料,又有净化水质的作用。

  13. Species and biogeochemical cycles of organic phosphorus in sediments from a river with different aquatic plants located in Huaihe River Watershed, China.

    Science.gov (United States)

    Yuan, He Zhong; Pan, Wei; Ren, Li Jun; Liu, Eeng Feng; Shen, Ji; Geng, Qi Fang; An, Shu Qing

    2015-01-01

    The results of phosphorus fractionation in the sediments from a contaminated river containing different aquatic plants, analyzed by solution 31P-NMR for Organic Phosphorus, showed that the concentration of Inorganic Phosphorus dominated in all species and Organic Phosphorus accounted for over 20% of Total Phosphorus. In general, orthophosphate was dominant in all the sampling sites. The proportion of Organic Phosphorus accounting for the Total Phosphorus in the sediments with different plant decreased in the following order: Paspalum distichum>Typha orientalis>Hydrilla verticillata. Phosphorus-accumulation ability of Paspalum distichum was obviously stronger than Typha orientalis and Hydrilla verticillata. The Organic Phosphorus was in aquatic plants dominated by humic-associated P (Hu-P), which converted to Inorganic Ohosphorus more significantly in submerged plants than in emerged plants. The sediment dominated by Paspalum distichum abundantly accumulated Organic Phosphorus in the orthophosphate monoester fraction. The degradation and mineralization of orthophosphate monoester was the important source of high Inorganic Phosphorus concentration and net primary productivity in Suoxu River. The Organic Phosphorus derived from Typha orientalis and Hydrilla verticillata was dramatically converted to Inorganic Phosphorus when the environmental factors varied.

  14. Ash characteristics and plant nutrients in some aquatic biomasses

    Science.gov (United States)

    Masto, Reginald; Pandit, Ankita; George, Joshy; Mukhopadhyay, Sangeeta; Selvi, Vetrivel; Ram, Lal

    2016-04-01

    Aquatic biomasses are explored as potential fuel source for direct combustion because of their faster growth and no land requirement. The energy density and the ash characteristics of the aquatic biomasses are to be evaluated for their suitability for energy extraction. In the study, four aquatic plant samples namely Eichornia crassipes, Hydrilla verticilleta, Lemna minor, Spirogyra spp were collected from a pond in Digwadih Campus of Central Institute of Mining and Fuel Research, Dhanbad. The biomasses were air dried, powdered and ashed at different temperatures. Volatile C was relatively lower in Spirogyra and Hydrilla (53 %) than Eichornia (62.6 %) or Lemna (59.7 %), whereas fixed C was higher for Eichornia and Lemna (about 10 %) and lower for Hydrilla (1 %). Ultimate analysis showed that the carbon content was in the order Eichornia > Lemna > Spirogyra > Hydrilla. The IR spectra of each raw biomass is compared to their respective ashes obtained at different temperatures (500-900°C). With increase in ashing temperature from 500-900°C there is gradual breakdown of the cellulosic structure hence, peaks around 2900-2800cm-1 caused by aliphatic C-H vibration tends to disappear slowly in ash. More number of peaks appears at lower wavenumbers in ashes of all the biomass samples indicating towards increased percentage of inorganic ion species. Considerable enrichment of SiO2 is validated with prominent peaks at 1100-900 cm-1 in all the ashes. Lemna and Spirogyra has a similar ash composition (Si > Al > Ca > K), whereas, Ca was higher in Hydrilla (Si > Ca > K > Al). Eichornia (Si > K > Ca > Al) has higher K and Ca than Al. SiO2 and Al2O3 were higher in Spirogyra, while SiO2 and CaO in Eichornia and Hydrilla. K first increased from 500-700/800⁰C, and then decreased from 800-900⁰C. Cl is lost slowly in ash from 500-700/800⁰C and then by a drastic reduction from 800-900⁰C. S is enhanced in ash at all temperatures although the change is quite small. Most of the Cl

  15. 不同水生植物对水体中氮磷吸收去除效果的试验%Experiment of Absorption and Removal Efficiency for Nitrogen and Phosphorus with Several Different Hydrophytes

    Institute of Scientific and Technical Information of China (English)

    苏小东; 李艳; 原金海; 贾云

    2014-01-01

    研究了狐尾藻、水蕴草、轮叶黑藻、长叶久冠和铜线草等水生植物吸收水体中N、P的能力。结果表明狐尾藻、水蕴草、轮叶黑藻和长叶久冠对水体中的氮磷有较强的去除能力,且植物对水体中氮磷的去除率与植物质量之间呈相关关系;同时狐尾藻、水蕴草、轮叶黑藻和长叶久冠均有较好的环境适应性,而铜线草的环境适应性较差。由此推断可以利用狐尾藻、水蕴草、轮叶黑藻和长叶久冠水生植物在生态塘污水处理系统中构建水生植物系统来处理生活污水。%Several hydrophytes named Myriophyllum Verticillatum,Elodea densa (Planch. )Casp. ,Hydrilla Verticillata,Echinodorus Uruguayensis and Paspalum pospaloides(Michx. )Scribn were used to investigate the ability of removal of nitrogen and phosphor in the sewage. The results show that Myriophyllum Verticillatum,Elodea densa (Planch. )Casp. ,Hydrilla Verticillata and Echinodorus Uruguayensis have a remarkable effect on removal of N and P,and the removal rates of hydrophytes on N and P have correlation to weight of hydrophytes. Myriophyllum Verticillatum, Elodea densa (Planch. ) Casp. , Hydrilla Verticillata and Echinodorus Uruguayensis have good environment adaptability,by which hydrophytes-based treatment system for ecological pond sewage treatment system can be constructed.

  16. STUDY OF AQUATIC ANGIOSPERMIC PLANTS OF ANAND CITY, GUJARAT, INDIA

    Directory of Open Access Journals (Sweden)

    K. R. PATEL1 AND N. K. PATEL2

    2014-06-01

    Full Text Available The present study deals with the taxonomic study of Aquatic Angiosperms growing throughout the Anand city. The plants are listed along with their brief taxonomic account of each species with current nomenclature, vernacular name, family and uses. The  collected plants are systematically observed during present work, During my study I observed various aquatic angiospermic plants such as   Ceratophyllum demersum, Colocasia esculenta, Eichhornia crassipes, Ipomoea aquatica, Nymphoides indicum, Ludwigia repens, Polygonum orientale, Typha elephantina, Lemna perpusilla, Spirodella polyrrhiza, Xanthium indicum, Phyllanthus reticulatus, Cynodon dactylon, Hydrilla verticillata were very common. Whereas Nymphaea nouchali, Polygonum barbatum, Scirpus articulatus were very rare in the study area.

  17. 污水处理中温度对黑藻生长的影响(英文)

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    [Objective] The research aimed to study the influence of temperature on the growth of Hydrilla verticillata in the wastewater treatment process.[Method] By using the single factor experiment design,four temperatures which were 5,15,25 and 35 ℃ were set.The growth situation of H.verticillata under the different temperatures was observed in the treatment process of domestic sewerage.[Result] H.verticillata grew luxuriantly at 35 and 25 ℃.Via the cultivation of 15 days,the plant length,branch number,root numbe...

  18. Suitability of aquatic biomass from Lake Toba (North Sumatra, Indonesia) for energy generation by combustion process

    Science.gov (United States)

    Brunerová, A.; Roubík, H.; Herák, D.

    2017-09-01

    Several aquatic plant species were identified as aquatic pollution of Lake Toba, North Sumatra (Indonesia); specifically, water hyacinth Eichhornia crassipes and aquatic weeds Hydrilla verticillata and Myriophyllum spicatum due to their high biomass yield which causes impenetrable mats at the bottom and surface of the lake. That complicates other vegetation growth and utilization of water areas for fishing or recreation. In attempt to clean the lake and prevent plants expansion, great amount of plants populations are removed from water but subsequent efficient utilization of such aquatic biomass is not ensured. Present research investigated energy potential of aquatic biomass originated from mentioned aquatic plants from Lake Toba and its possible utilization for energy production by direct combustion. Performed chemical analysis contained from determination of moisture, ash and volatile matter contents and calorific values. Evaluation of results proved highest suitability and energy potential of Eichhornia crassipes with gross calorific value (GCV) 16.31 MJ·kg–1, followed by Hydrilla verticillata with GCV 15.24 MJ·kg–1. Samples of Myriophyllum spicatum exhibited unsatisfactory results due to its low GCV (11.27 MJ·kg–1) in combination with high ash content (36.99%) which indicates complications during combustion, thus, low energy production efficiency and overall unsuitability for combustion purposes.

  19. The distribution of submersed aquatic vegetation and water lettuce in the fresh and oligohaline tidal Potomac River, 2007

    Science.gov (United States)

    Campbell, Sarah Hunter; Rybicki, Nancy B.; Schenk, Edward R.

    2015-01-01

    Surveys documenting the composition of species of submersed aquatic vegetation (SAV) have been conducted in the Potomac River for decades. These surveys can help managers assess the proportion of native and exotic plants in the river or can be used to determine relationships between native and exotic plants, environmental conditions, and wildlife. SAV coverage increased from 2005 to 2007 throughout the fresh and oligohaline study area. The 2007 survey documented here determined that eleven species of SAV were present. The abundance of the exotic species Hydrilla verticillata (hydrilla) was relatively low, and species diversity was relatively high compared to previous years. The survey also revealed a new population of the invasive, floating aquatic plant Pistia stratiotes (water lettuce). In 2007, water lettuce, the latest exotic aquatic plant to be found in the fresh to oligohaline portion of the Potomac River, was most abundant in Mattawoman Creek, Charles County, Maryland. However, it was not observed in the fresh to oligohaline portion of the Potomac River in the summer of 2008. An understanding of the distribution of SAV species and factors governing the abundance of native and invasive aquatic species is enhanced by long-term surveys.

  20. Adsorption of Arsenite by Six Submerged Plants from Nansi Lake, China

    Directory of Open Access Journals (Sweden)

    Zhibin Zhang

    2014-01-01

    Full Text Available Nansi Lake is the largest and the most important freshwater lake in north China for the South-North Water Transfer Project. Due to long-time and large-scale fish farming of history, the excess fish food and excretion usually release pentavalent arsenic, which is converted into trivalent arsenic (As (III in the lake sediment and released into lake water. Adsorption of arsenite using six submerged plants (Mimulicalyx rosulatus, Potamogeton maackianus, Hydrilla, Watermifoil, Pteris vittata, and Potamogeton crispus as adsorbing materials was investigated. The experimental data obtained have been analyzed using Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models and the pseudo-first-order, pseudo-second-order, and intraparticle diffusion kinetics models. According to the results, the As (III equilibrium data agreed well with the Freundlich isotherm model. The adsorption capacity of the plants was in the following order: Potamogeton crispus > Pteris vittata > Potamogeton maackianus > Mimulicalyx rosulatus > Hydrilla > Watermifoil. The sorption system with the six submerged plants was better described by pseudo-second-order than by first-order kinetics. Moreover, the adsorption with Potamogeton crispus could follow intraparticle diffusion (IPD model. The initial adsorption and rate of IPD using Potamogeton crispus and Pteris vittata were higher than those using other plants studied.

  1. Domestic Wastewater Treatment Miniplan of Institution Using a Combination of “Conetray Cascade Aerator” Technology and Biofilter

    Directory of Open Access Journals (Sweden)

    Naniek Ratni Juliardi A.R

    2016-01-01

    Full Text Available In Indonesia, the contamination from domestic wastewater is becoming the greatest pollutant and reaches up to 85% that goes into the body of water. This might worsen the river water quality. To anticipate this condition, there should be some way out, by making use of wastewater as a source of energy. One of those systems is by employing Cone-tray Cascade Aerator combined with Biofilter by using Hydrilla plant which can be used as an alternative of waste water treatment for both domestic and institutional scale. This research was aimed at determining the system capability of aeration combined with biofilter by using hydrilla plant to reduce or eliminate the pollutant load of BOD, COD, and TSS. This research was conducted in a continuous stream of water at 200L/hour. The result showed that the best system of Conetray Cascade Aerator combined with biofilter could reduce BOD as much as 69,11%, COD at 61,14%, and TSS at 65,45%.

  2. Mechanical harvesting of aquatic plants. Report 3. Evaluation of the Limnos System

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.L.

    1984-05-01

    The Limnos Mechanical Harvesting System consists of a separate cutter machine; a harvester, which includes a gathering and conveyor pickup unit and a processor; and two transport tank barges. System operational tests were conducted on the Withlacoochee River in central Florida during the summer of 1979. Plants harvested were primarily topped-out hydrilla with small amounts of waterhyacinth. Productivity of the cutter unit was evaluated separately and in conjunction with the harvester. Tests were conducted with the harvester with the tank barges to remove the plant material from the water and also without the barges, which allowed the processed plant materials to be discharged directly into the water body. High productivity of the harvester in dense hydrilla (and water-hyacinth mixtures) required reducing the width of cut of the plant material or using 18-ft cuts at two depths (3 and 6 ft). This procedure limited the mass of material that had to be handled by the harvester. Several potential areas requiring additional research were identified as a result of these tests: improved procedures for evaluating mechanical harvesting machines, and possible improvements to the Limnos harvester system to allow higher productivity. 5 figures, 4 tables.

  3. The growth of three submerged plants in different polluted water and its impact on water quality%3种沉水植物在不同污染水体中的生长及其对水质的影响

    Institute of Scientific and Technical Information of China (English)

    吴旻; 赵群芬

    2015-01-01

    In this paper, three submerged plants (goldfish algae(Ceratophyllum demersum L.), bitter grass(Hydrilla verticillata)and hydrilla(Vallisneria natans (Lour.) Hara)) were chosen as the research object and placed in different polluted water to explore different submerged plant’s purification effect on the water quality by monitoring water’s total nitrogen, total phosphorus. chlorophyll a content, and pH, etc. At the same time, based on the total nitrogen and total phosphorus content in plant and superoxide enzyme (SOD), malondialdehyde (MDA), the growth of the plants in different polluted water was researched. The results showed that the purification effects of different submerged plants have a significant difference on different polluted water, and the stress of different polluted water on the physical growth of submerged plant also has different effects.%以金鱼藻(Ceratophyllum demersum L.)、苦草(Hydrilla verticillata)、黑藻(Vallisneria natans (Lour.) Hara)3种沉水植物作为研究对象,分别将其放置于不同污染水体中培养,通过监测水体总氮、总磷、叶绿素a含量和pH值等,探究不同沉水植物对水质的净化效果;同时通过对植物体内总氮、总磷含量以及超氧化物酶(SOD)、丙二醛(MDA)的变化,研究植物在不同污染水体中的生长情况。结果表明,不同沉水植物对不同污染水体的净水效果有着显著差异,不同污染水体的胁迫作用对沉水植物本身的生理生长也有着不同的影响。综合所研究的沉水植物的净水优势以及在不同污染水体中的适应情况,筛选出在各种污染水体中的优势种,归纳总结出生态修复组合的方案。

  4. Reproduction ecology of Pinus halepensis : a monoecious, wind-pollinated and partially serotinous Mediterranean pine tree

    NARCIS (Netherlands)

    Goubitz, Shirrinka

    2002-01-01

    Fire is an important factor in the evolution and ecology of Mediterranean plant species. The fire frequency has increased in the 20st century. Pines are the most important tree species in the area. Pinus halepensis is the only natural pine in parts of the east Mediterranean basin, such as Israel and

  5. Optimization of selection contribution and mate allocations in monoecious tree breeding populations

    Directory of Open Access Journals (Sweden)

    Waldmann Patrik

    2009-11-01

    Full Text Available Abstract Background The combination of optimized contribution dynamic selection and various mating schemes was investigated over seven generations for a typical tree breeding scenario. The allocation of mates was optimized using a simulated annealing algorithm for various object functions including random mating (RM, positive assortative mating (PAM and minimization of pair-wise coancestry between mates (MCM all combined with minimization of variance in family size and coancestry. The present study considered two levels of heritability (0.05 and 0.25, two restrictions on relatedness (group coancestry; 1 and 2% and two maximum permissible numbers of crosses in each generation (100 and 400. The infinitesimal genetic model was used to simulate the genetic architecture of the trait that was the subject of selection. A framework of the long term genetic contribution of ancestors was used to examine the impacts of the mating schemes on population parameters. Results MCM schemes produced on average, an increased rate of genetic gain in the breeding population, although the difference between schemes was small but significant after seven generations (up to 7.1% more than obtained with RM. In addition, MCM reduced the level of inbreeding by as much as 37% compared with RM, although the rate of inbreeding was similar after three generations of selection. PAM schemes yielded levels of genetic gain similar to those produced by RM, but the increase in the level of inbreeding was substantial (up to 43%. Conclusion The main reason why MCM schemes yielded higher genetic gains was the improvement in managing the long term genetic contribution of founders in the population; this was achieved by connecting unrelated families. In addition, the accumulation of inbreeding was reduced by MCM schemes since the variance in long term genetic contributions of founders was smaller than in the other schemes. Consequently, by combining an MCM scheme with an algorithm that optimizes contributions of the selected individuals, a higher long term response is obtained while reducing the risk within the breeding program.

  6. Functional monoecy due to delayed anther dehiscence: a novel mechanism in Pseuduvaria mulgraveana (Annonaceae).

    Science.gov (United States)

    Pang, Chun-Chiu; Scharaschkin, Tanya; Su, Yvonne C F; Saunders, Richard M K

    2013-01-01

    Unlike most genera in the early-divergent angiosperm family Annonaceae, Pseuduvaria exhibits a diversity of floral sex expression. Most species are structurally andromonoecious (or possibly androdioecious), although the hermaphroditic flowers have been inferred to be functionally pistillate, with sterile staminodes. Pseuduvaria presents an ideal model for investigating the evolution of floral sex in early-divergent angiosperms, although detailed empirical studies are currently lacking. The phenology and pollination ecology of the Australian endemic species Pseuduvaria mulgraveana are studied in detail, including evaluations of floral scent chemistry, pollen viability, and floral visitors. Results showed that the flowers are pollinated by small diurnal nitidulid beetles and are protogynous. Pollen from both hermaphroditic and staminate flowers are shown to be equally viable. The structurally hermaphroditic flowers are nevertheless functionally pistillate as anther dehiscence is delayed until after petal abscission and hence after the departure of pollinators. This mechanism to achieve functional unisexuality of flowers has not previously been reported in angiosperms. It is known that protogyny is widespread amongst early-divergent angiosperms, including the Annonaceae, and is effective in preventing autogamy. Delayed anther dehiscence represents a further elaboration of this, and is effective in preventing geitonogamy since very few sexually mature flowers occur simultaneously in an individual. We highlight the necessity for field-based empirical interpretations of functional floral sex expression prior to evaluations of evolutionary processes.

  7. Reproduction ecology of Pinus halepensis : a monoecious, wind-pollinated and partially serotinous Mediterranean pine tree

    NARCIS (Netherlands)

    Goubitz, Shirrinka

    2001-01-01

    Fire is an important factor in the evolution and ecology of Mediterranean plant species. The fire frequency has increased in the 20st century. Pines are the most important tree species in the area. Pinus halepensis is the only natural pine in parts of the east Mediterranean basin, such as Israel and

  8. [Bioremediation efficiency of applying Daphnia magna and submerged plants: a case study in Dishui Lake of Shanghai, China].

    Science.gov (United States)

    Huo, Yuan-Zi; He, Wen-Hui; Luo, Kun; Wang, Yang-Yang; Zhang, Yin-Jiang; Tian, Qian-Tao; He, Pei-Min

    2010-02-01

    From April 2007 to January 2008, a bioremediation experiment was conducted in a diversion channel of D-port pilot area of Dishui Lake (the channel length is 950 m, and its water volume is 10000 m3). Daphnia magna was first introduced to filter the high biomass of phytoplankton and other particulate organic matter, and then, five submerged plant species Elodea canadensis, Vallisneria spiralis, Hydrilla verticillata, Potamogeton lucens, and Potamogeton crispus were transplanted. Water samples were collected monthly to monitor the water quality and to investigate the bioremediation efficiency. Ten months monitoring data showed that in the remediation area, the water body's total nitrogen (TN), ammonium nitrogen (NH4(+)-N), nitrate nitrogen (NO3(-)-N), nitrite nitrogen (NO2(-)-N), total phosphorus (TP), and reactive phosphate (PO4(3-)-P) concentrations and chemical oxygen demand (COD) were significantly lower (P study demonstrated the effectiveness of introducing D. magna and transplanting submerged plants in improving the water quality of Dishui Lake.

  9. Non-contact intracellular binding of chloroplasts in vivo

    Science.gov (United States)

    Li, Yuchao; Xin, Hongbao; Liu, Xiaoshuai; Li, Baojun

    2015-06-01

    Non-contact intracellular binding and controllable manipulation of chloroplasts in vivo was demonstrated using an optical fiber probe. Launching a 980-nm laser beam into a fiber, which was placed about 3 μm above the surface of a living plant (Hydrilla verticillata) leaf, enabled stable binding of different numbers of chloroplasts, as well as their arrangement into one-dimensional chains and two-dimensional arrays inside the leaf without damaging the chloroplasts. Additionally, the formed chloroplast chains were controllably transported inside the living cells. The optical force exerted on the chloroplasts was calculated to explain the experimental results. This method provides a flexible method for studying intracellular organelle interaction with highly organized organelle-organelle contact in vivo in a non-contact manner.

  10. Bioenergy potential of eight common aquatic weeds

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, S.A.; Nipaney, P.C.; Schaumberg, G.D. (Pondicherry (Central) Univ. (IN). Salim Ali School of Ecology)

    1990-01-01

    Eight common aquatic weeds Salvinia molesta, Hydrilla verticillata, Nymphaea stellata, Azolla pinnata, Ceratopteris sp. Scirpus sp. Cyperus sp, and Utricularia reticulata were digested anaerobically to produce methane. The carbon to nitrogen (C/N) ratio, carbon to phosphorus (C/P) ratio, and the volatile solids (VS) content of the weeds varied widely. No trend between these factors and the methane yield was discernable; the possible reasons are discussed. The energy potential of the weeds per unit area of the weed crop was worked out. Natural stands of salvinia, such as the one employed in the present investigation, would yield energy (methane) of the order of 10{sup 8} Kcal/ha/yr. (author).

  11. Remote sensing analysis of Lake Livingston aquatic plants

    Science.gov (United States)

    Benton, A. R., Jr.; Newman, R. M.

    1976-01-01

    Results obtained during 1975 to monitor the growth of aquatic plants in the Lake Livingston area, using remote sensing photographic imagery, were described. Sequential total coverage was provided of the Jungle and White Rock Creek, plus coverage of smaller areas of localized infestation downlake, including Brushy Creek, KOA Kampground Marina, Penwaugh Slough, Memorial Point Marina, the Beacon Bay marinas and Pine Island. The imagery was generally good, photographic exposure being increased as the season progressed in order to obtain better pictures of the submerged vegetation. Some very significant differences in growth patterns, species interaction, and species dominance were observed when compared to 1974. Observation of the following plants was discussed: water hyacinth, hydrilla, coontail, potamageton. In general, the level of infestation was lower in 1975 than in 1974, due to the combined effect of more systematic application of herbicides and harsher intervening winter weather conditions.

  12. Heavy metal induced DNA changes in aquatic macrophytes: Random amplified polymorphic DNA analysis and identification of sequence characterized amplified region marker

    Institute of Scientific and Technical Information of China (English)

    Meetu Gupta; Neera Bhalla Sarin

    2009-01-01

    Plants have been used as good bio-indicators and genetic toxicity of environmental pollution in recent years. In this study, aquatic plants Hydrilla verticillata and Ceratophyllum demersum treated with 10 mol/L Cd, 5 mol/L Hg, and 20 mol/L Cu for 96 h, showed changes in chlorophyll, protein content, and in DNA profiles. The changes in DNA profiles included variation in band intensity, presence or absence of certain bands and even appearance of new bands. Genomic template stability test performed for the qualitative measurement of changes in randomly amplified polymorphic DNA (RAPD) profiles, showed significant effect at the given concentration of metals. Cloning and sequencing of bands suggested that these markers although may not be homologous to any known gene but its conversion as a sequence characterized amplified region (SCAR) marker is useful in detecting the effects of genotoxin agents.

  13. Does mechanical disturbance affect the performance and species composition of submerged macrophyte communities?

    Science.gov (United States)

    Zhang, Qian; Xu, Ying-Shou; Huang, Lin; Xue, Wei; Sun, Gong-Qi; Zhang, Ming-Xiang; Yu, Fei-Hai

    2014-01-01

    Submerged macrophyte communities are frequently subjected to disturbance of various frequency and strength. However, there is still little experimental evidence on how mechanical disturbance affects the performance and species composition of such plant communities. In a greenhouse experiment, we constructed wetland communities consisting of five co-occurring clonal submerged macrophyte species (Hydrilla verticillata, Elodea canadensis, Ceratophyllum demersum, Chara fragilis, and Myriophyllum spicatum) and subjected these communities to three mechanical disturbance regimes (no, moderate and strong disturbance). Strong mechanical disturbance greatly decreased overall biomass, number of shoot nodes and total shoot length, and increased species diversity (evenness) of the total community. It also substantially decreased the growth of the most abundant species (H. verticillata), but did not affect growth of the other four species. Our data reveal that strong disturbance can have different effects on different submerged macrophyte species and thus alters the performance and species composition of submerged macrophyte communities. PMID:24811826

  14. The Distribution of Submersed Aquatic Vegetation in the Fresh and Oligohaline Tidal Potomac River, 2005

    Science.gov (United States)

    Rybicki, Nancy B.; Justiniano-Velez, Erika M.; Schenk, Edward R.; Baldizar, Julie M.; Hunter, Sarah E.

    2008-01-01

    Submersed aquatic vegetation (SAV) is a critical component of the Potomac River ecosystem. Though SAV provides important habitat for fauna and stabilizes bottom sediment, very dense beds may restrict recreational and commercial navigation. Exotic species of SAV are managed by the Metropolitan Washington Council of Governments Potomac Aquatic Plant Management Program (PAPMP). Selected beds of primarily exotic SAV species that limit navigation are harvested mechanically. The program began in 1986 when approximately 40 acres of plants were harvested from 18 sites (Metropolitan Washington Council of Governments 1987). Monitoring efforts are an effective means of quantifying the distribution and abundance of the exotic species, Hydrilla verticillata (hydrilla) and other SAV species. These annual surveys provide a basis for identifying large-scale changes and trends throughout the ecosystem and allow managers to evaluate the effectiveness of resource management policies based on a reliable scientific foundation (Rybicki and Landwehr, 2007). The U.S. Geological Survey (USGS) has monitored the distribution and composition of SAV beds in the fresh and oligohaline (salinity 0.5 to 5) tidal Potomac River since 1978 using transect sampling (1978 to 1981, 1985 to 1987, and 2002) and shoreline surveys (1983 to 2005). The Government of the District of Columbia has monitored the portion of the Potomac and Anacostia Rivers within Washington DC since 1998 (Rottman, 1999; Ryan, 2005, 2006). The species of SAV observed in beds in the tidal Potomac River are incorporated into the Virginia Institute of Marine Science (VIMS) annual report on SAV distribution in Chesapeake Bay. The VIMS report and methods are available at http://www.vims.edu/bio/sav (Orth et al., 2006). Additional publications concerning SAV distribution in the Potomac River can be found at http://water.usgs.gov/nrp/proj.bib/sav/wethome.htm.

  15. Habitat loss other than fragmentation per se decreased nuclear and chloroplast genetic diversity in a monoecious tree.

    Science.gov (United States)

    Zhang, Xin; Shi, Miao-Miao; Shen, Dong-Wei; Chen, Xiao-Yong

    2012-01-01

    Generally, effect of fragmentation per se on biodiversity has not been separated from the effect of habitat loss. In this paper, using nDNA and cpDNA SSRs, we studied genetic diversity of Castanopsis sclerophylla (Lindl. & Paxton) Schotty populations and decoupled the effects of habitat loss and fragmentation per se. We selected seven nuclear and six cpDNA microsatellite loci and genotyped 460 individuals from mainland and island populations, which were located in the impoundment created in 1959. Number of alleles per locus of populations in larger habitats was significantly higher than that in smaller habitats. There was a significant relationship between the number of alleles per locus and habitat size. Based on this relationship, the predicted genetic diversity of an imaginary population of size equaling the total area of the islands was lower than that of the global population on the islands. Re-sampling demonstrated that low genetic diversity of populations in small habitats was caused by unevenness in sample size. Fisher's α index was similar among habitat types. These results indicate that the decreased nuclear and chloroplast genetic diversity of populations in smaller habitats was mainly caused by habitat loss. For nuclear and chloroplast microsatellite loci, values of F(ST) were 0.066 and 0.893, respectively, and the calculated pollen/seed dispersal ratio was 162.2. When separated into pre-and post-fragmentation cohorts, pollen/seed ratios were 121.2 and 189.5, respectively. Our results suggest that habitat loss explains the early decrease in genetic diversity, while fragmentation per se may play a major role in inbreeding and differentiation among fragmented populations and later loss of genetic diversity.

  16. Improvements in the use of aquatic herbicides and establishment of future research directions

    Science.gov (United States)

    Getsinger, K.D.; Netherland, M.D.; Grue, C.E.; Koschnick, T.J.

    2008-01-01

    Peer-reviewed literature over the past 20 years identifies significant changes and improvements in chemical control strategies used to manage nuisance submersed vegetation. The invasive exotic plants hydrilla (Hydrilla verticillata L.f. Royle) and Eurasian watermilfoil (Myriophyllum spicatum L.) continue to spread and remain the plant species of greatest concern for aquatic resource managers at the national scale. Emerging exotic weeds of regional concern such as egeria (Egeria densa Planch.), curlyleaf pondweed (Potamogeton crispus L.), and hygrophila (Hygrophila polysperma (Roxb.) T. Anders), as well as native plants such as variable watermilfoil (Myriophyllum heterophyllum Michx), and cabomba (Cabomba caroliniana Gray) are invasive outside their home ranges. In addition, there is always the threat of new plant introductions such as African elodea (Lagarosiphon major (Ridley) Moss) or narrow-leaf anacharis (Egeria najas Planchon). The registration of the bleaching herbicide fluridone in the mid 1980s for whole-lake and large-scale management stimulated numerous lines of research involving reduction of use rates, plant selectivity, residue monitoring, and impacts on fisheries. In addition to numerous advances, the specificity of fluridone for a single plant enzyme led to the first documented case of herbicide resistance in aquatic plant management. The resistance of hydrilla to fluridone has stimulated a renewed interest by industry and others in the registration of alternative modes of action for aquatic use. These newer chemistries tend to be enzyme-specific compounds with favorable non-target toxicity profiles. Registration efforts have been facilitated by increased cooperation between key federal government agencies that have aquatic weed control and research responsibilities, and regulators within the U.S. Environmental Protection Agency (USEPA). We reviewed past and current research efforts to identify areas in need of further investigation and to establish

  17. Attempts to reproduce vacuolar myelinopathy in domestic swine and chickens.

    Science.gov (United States)

    Lewis-Weis, Lynn A; Gerhold, Richard W; Fischer, John R

    2004-07-01

    Avian vacuolar myelinopathy (AVM) was first recognized as a cause of bald eagle (Haliaeetus leucocephalus) mortality in 1994 in Arkansas (USA) and has since caused over 90 bald eagle and numerous American coot (Fulica americana) mortalities in five southeastern states. The cause of AVM remains undetermined but is suspected to be a biotoxin. Naturally occurring AVM has been limited to wild waterbirds, raptors, and one species of shorebird, and has been reproduced experimentally in red-tailed hawks (Buteo jamaicensis). In this study, chickens and swine were evaluated for susceptibility to vacuolar myelinopathy with the intent of developing animal models for research and to identify specific tissues in affected coots that contain the causative agent. Additionally, submerged, aquatic vegetation, primarily hydrilla (Hydrilla verticillata), and associated material collected from a reservoir during an AVM outbreak was fed to chickens in an effort to reproduce the disease. In two separate experiments, six 4-wk-old leghorn chickens and ten 5-wk-old leghorn chickens were fed coot tissues. In a third experiment, five 3-mo-old domestic swine and one red-tailed hawk, serving as a positive control, were fed coot tissues. In these experiments, treatment animals received tissues (brain, fat, intestinal tract, kidney, liver, and/or muscle) from coots with AVM lesions collected at a lake during an AVM outbreak. Negative control chickens and one pig received tissues from coots without AVM lesions that had been collected at a lake where AVM has never been documented. In a fourth experiment, eight 3-wk-old leghorn chickens were fed aquatic vegetation material. Four chickens received material from the same lake from which coots with AVM lesions were collected for the previous experiments, and four control chickens were fed material from the lake where AVM has never been documented. Blood was collected and physical and neurologic exams were conducted on animals before and once per week

  18. 不同磷营养水平对2种沉水植物在Cd·Zn复合污染下的影响%Effects of Different Phosphorus Concentrations on Two Submerged Plants under Combined Pollution of Cd, Zn

    Institute of Scientific and Technical Information of China (English)

    张慧; 王超; 王沛芳; 薛艳

    2011-01-01

    [目的]揭示富营养化和重金属污染共同存在时对沉水植物的影响,为水生生态系统的健康评价和治理提供理论依据和手段.[方法]比较研究了不同磷营养水平对Cd、Zn复合污染下伊乐藻(Elodea nuttallii)、黑藻(Hydrilla verticillata)2种沉水植物叶绿素含量和叶绿素a/b比值、MDA含量、GSH含量、POD活性、CAT活性等生理生化指标的影响.[结果]随着培养时间延长,2种植物的叶绿素含量基本呈下降趋势,MDA含量呈先上升后下降趋势,POD活性及可溶性蛋白含量呈先下降后上升趋势,GSH呈缓慢上升趋势,当不存在磷水平时CAT活性无明显变化;但是黑藻比伊乐藻对胁迫更敏感,并且耐性优于伊乐藻.[结论]不同磷营养水平对受重金属胁迫植物的影响不一样,其中低磷水平(0.05 mg/L)可在一定程度上级解重金属的毒害,与重金属产生拮抗作用;而高磷水平(5 mg/L)则加重了重金属对植物的伤害,产生协同作用.%[ Objective ] The aim was to reveal effects of eutrophication on two kinds of submerged plant under heavy metal contamination, thus to provide theoretical basis for health evaluation and treatment measures of aquatic ecosystems. [ Method ] The effects of different phosphorus levels on the chlorophyll contents and a/b values of Elodea nuttallii and Hydrilla verticillata were compared and investigated. [ Result ] With the culture time prolonging, the chlorophyll contents of the two kinds of plant showed a general decreasing tendency ; MDA content was first increased and then decreased; POD activity and soluble protein content were furst decreased and then increased; GSH showed a slow upward trend; there was no significant change in CAT activity when no phosphorus existed; in addition, Elodea nuttallii had better sensitivity and tolerance to the stress than Hydrilla verticillata. [ Conclusion ] Effects of different phosphorus levels on the plants under heavy metal stress differed

  19. Purification and Influence of Submerged Plants on Water Quality of Landscape Water Body Supplied by Reclaimed Water%沉水植物对再生水景观水体水质变化的影响和净化效果

    Institute of Scientific and Technical Information of China (English)

    徐志嫱; 刘维; 赵洁; 刘玉玲

    2012-01-01

    This research is to investigate the eutrophication change and water quality improvement by submerged plants in a landscape pond supplied by reclaimed water.An artificial lake of Xi'an was chosen to monitor the water quality at different locations and periods.An outdoor study was carried out to research the effects of nutrient removal by Elodea canadensis and Hydrilla verticillata in reclaimed water.The results showed that concentrations of ammonia nitrogen(NH+4-N) and total nitrogen(TN) were clearly lower than the open water area,and the water was in low eutrophication state in the area with submerged plants,mainly located at the edge of the lake.Elodea canadensis and Hydrilla verticillata showed a perfect effect for reclaimed water quality.The removal rates of Elodea canadensis of CODCr,TN and TP were 38.55%~57.54%,43.13%~51.81% and 61.76%~77.45% respectively,that were superior to Hydrilla verticillata's.Elodea canadensis had inhibitory effect on algae,and chlorophyll a kept in 20 μg/L level during long time.It was suggested that Elodea canadensis should be used as the pioneer plants for restoration of landscape water body supplied by reclaimed water in the northwest area.%为揭示沉水植物对以再生水作为水源的景观水体富营养化变化趋势的影响和对水体水质的维持和改善作用,对西安市一个再生水景观水体开展了不同区域和不同季节的水质监测试验,并采用室外玻璃缸装置研究伊乐藻和轮叶黑藻对再生水中氮、磷等营养盐的去除效果。结果表明:有沉水植物生长的区域氨氮、总氮浓度明显低于主湖区,且水质能够维持在低富营养化状态。伊乐藻和轮叶黑藻对再生水水质具有良好的改善作用,且伊乐藻优于轮叶黑藻。伊乐藻对再生水中CODCr、氮、磷的去除率分别为38.55%~57.54%,43.13%~51.81%和61.76%~77.45%,可使水体中叶绿素a含量维持在20μg/L左右,对藻类具有较好的抑制作

  20. 上海后滩湿地沉水植物群落系统对底泥的生态修复效应%On the effects of the submerged macrophyte community systems on the sedimentary restoration of Shanghai Houtan wetland

    Institute of Scientific and Technical Information of China (English)

    董悦; 霍姮翠; 谢文博; 杜佳沐; 罗思亭; 王聪; 张饮江

    2013-01-01

    利用5种不同沉水植物群落系统对中国2010上海世博区后滩湿地底泥进行生态修复,于2009年8月-2010年8月对沉水植物覆盖度与生物量,以及底泥有机质(0M)、总氮(TN)、总磷(TP)的分布与变化进行动态监测.结果表明:沉水植物群落覆盖度、生物量有明显的季节变化,总体呈升高趋势,且与底泥OM、TN、TP呈正相关;底泥经修复后,OM质量分数、TN和TP质量比分别比背景值降低61.9%~79.7%、78.7%~ 83.9%、32.3%~42.7%;底泥有机指数从Ⅳ级(有机污染)降至Ⅱ级(较清洁),降低了水体富营养化的风险;2010年8月各净化区沉水植物群落数量特征均高于2009年8月,l区的伊乐藻(Elodea nuttallii)、狐尾藻(Myriophyllumverticillatum)、轮叶黑藻(Hydrilla verticillata)、金鱼藻(Ceratophyllum demersum L.)群落以及2区的苦草(Vallisneria natans(Lour.) Hara)、金鱼藻(Ceratophyllum demersum L.)、轮叶黑藻(Hydrilla verticillata)对营养物的去除效果较其他净化区显著;底泥OM质量分数、TN质量比在垂直的0~30 cm内分布较一致,TP质量比在0~15 cm内降低,在15 ~ 30 cm内升高.研究表明,后滩湿地沉水植物群落系统对底泥营养盐修复效果明显,沉水植物群落逐渐趋于稳定,具有一定可持续性.

  1. Eutrophication increases methane emission to the atmosphere in tropical lagoons: insights from two Ivory Coast sites

    Science.gov (United States)

    José-mathieu Koné, Yéfanlan; Vieira Borges, Alberto

    2017-04-01

    Eutrophication increases methane emission to the atmosphere in tropical lagoons: insights from two Ivory Coast sites. Y J M Koné (1) & A.V. Borges (2) (1) Centre de recherches océanologiques (CRO) d'Abidjan, (Ivory Coast) (2) University of Liège, Chemical Oceanography Unit, Liège, Belgium (Belgium) Eutrophication is a worldwide environmental problem and a definitive solution is far from being achieved, despite the large number of studies documenting its causes. In small aquatic ecosystems, excessive growth of macrophytes is a well known undesirable consequence of eutrophication. When these plants die and sink to the bottom the decomposing biomass depletes oxygen content in the water column thus leading to anoxia promoting methane (CH4) production. Here, we reported the CH4 data obtained during six campaigns covering the annual cycle in two small lagoons of Ivory Coast (Ono, Kodjoboué) that are contrasted in the degree of eutrophication and the corresponding coverage of macrophytes (e.g. Echinochloa pyramidalis, Eichhornia crassipes, Hydrilla verticillata). Our data showed a high spatio-temporal variability of CH4 within the lagoons and between the two systems, with CH4 concentrations in surface waters ranging between 80 to 74,604 nmol L-1. The highest CH4 concentration values were observed in the eutrophic Ono lagoon that is covered by 80% of macrophytes, suggesting that lagoons dominated by macrophytes are significant sources of CH4 toward the atmosphere.

  2. Physico-chemical assessment of paper mill effluent and its heavy metal remediation using aquatic macrophytes--a case study at JK Paper mill, Rayagada, India.

    Science.gov (United States)

    Mishra, Swayamprabha; Mohanty, Monalisa; Pradhan, Chinmay; Patra, Hemanta Kumar; Das, Ritarani; Sahoo, Santilata

    2013-05-01

    The present investigation aims to assess the phytoremediation potential of six aquatic macrophytes, viz. Eichhornia crassipes, Hydrilla verticillata, Jussiaea repens, Lemna minor, Pistia stratiotes and Trapa natans grown in paper mill effluent of JK Paper mill of Rayagada, Orissa, for remediation of heavy metals. The experiment was designed in pot culture experiments. Assessment of physico-chemical parameters of paper mill effluent showed significant decrease in pH, conductivity, total dissolved solids, total suspended solids, chlorine, sulphur, biological and chemical oxygen demand after growth of macrophytes for 20 days. Phytoremediation ability of these aquatic macrophytic species for copper (Cu) and mercury (Hg) was indicated by assessing the decrease in the levels of heavy metals from effluent water. Maximum reduction (66.5 %) in Hg content of untreated paper mill effluent was observed using L. minor followed by T. natans (64.8 %). L. minor showed highest reduction (71.4 %) of Cu content from effluent water followed by E. crassipes (63.6 %). Phytoextraction potential of L. minor was remarkable for Hg and Cu, and bioaccumulation was evident from bioconcentration factor values, i.e. 0.59 and 0.70, respectively. The present phytoremediation approach was considered more effective than conventional chemical treatment method for removing toxic contaminants from paper mill effluent.

  3. Descriptions and Seasonal Variations of Various Biotopes and Ecotones of Indus River Bed at Chashma Barrage, Pakistan

    Directory of Open Access Journals (Sweden)

    Tahira Hussain

    2015-02-01

    Full Text Available The aim of the study was to find the diversity index of flora, investigation of species at pond area and biomass calculation of economic plants at Chashma Barrage, Pakistan. The study area consisted of river Bella, pond area and eastern edge of river bed near Ali Wali Ghandi village at Chashma Barrage. The seasonal variation in the abundance of floral species was also related with the increase in temperature. Cyperus deformus, Phragmites kerka, Saccharum spontaneum were most abundant in the river ‘Bella’ habitat. Persicassia amphibian, Cyperus deformus and Polygonum royleanum were abundant in Aliwali Ghandi habitat. Aquatic plants of families Potamogetonaceae, Nymphaeaceae, Najadaceae and Hydrocharitaceae were most common in pond area . The ecotones were wide and variable between the aquatic biotopes and the river bed biotopes. On the Aliwali Ghandi site the moist soil with puddles and small channels of water were found and Cyperus deformus biotope prevailed. In the river ‘Bella’ site Phragmites, Sacharum was the biotope and in water Hydrilla biotope was recorded. An increase in biomass of Phragmites, Sacharum and Typha was recorded with the passage of time. The species of the area have significant importance in socio economics of the local community of Chashma Barrage.

  4. Phytoplankton community of Lake Baskandi anua, Cachar District, Assam, North East India – An ecological study

    Directory of Open Access Journals (Sweden)

    Devi M.B.

    2016-01-01

    Full Text Available Diversity, relative abundance and dominance of phytoplankton community of the Lake Baskandi anua, an oxbow lake of Assam, North east India were studied during December 2009 to November 2010. Chlorophyll content and biomass of phytoplankton along with physico-chemical properties of water of the lake were also estimated. The lake is covered with Hydrilla and other macrophytes like Eichhornia, Trapa, Altrnenthera, Polygonum, Ludwizia sp., etc. Seasonal fluctuations of 41 genera of phytoplankton, belonging to 5 groups (Chlorophyceae, Cyanobacteria, Bacillariophyceae, Euglenophyceae and Dinophyceae were encountered in the lake. Chlorophyceae was found to be highest in winter, Cyanobacteria and Euglena in monsoon and Bacillariophyceae in pre monsoon. According to Engelmann’s scale, Spirogyra indica was found eudominant followed by 10 dominant, 24 subdominant and 20 recedent species. Chlorophyll- a content of phytoplankton varied from 14.18 to 33.89 μg·L-1, during the study period. One way analysis of variance (ANOVA revealed significant seasonal variation in physico-chemical properties of water like Water temperature, pH, Conductivity, Dissolved oxygen, Free CO2, Total alkalinity, Calcium, Chloride, Nitrate and Ammonia. Relationship between phytoplankton group assemblage and environmental variables were explored by the ordination method CCA (Canonical Correspondence Analysis.

  5. Performa Udang Hias Red Cherry (Neocaridina heteropoda pada Fase Pembesaran Melalui Aplikasi Warna Wadah Berbeda

    Directory of Open Access Journals (Sweden)

    I Wayan Subamia

    2016-03-01

    Full Text Available Shrimp red cherry shrimp is one of the ornamental potential developed. One of the conservation efforts can be made to increase production by optimizing keragaannya on enlargement phase. This study aims at scaling up the production of red cherry shrimp, especially in the phase of enlargement. Treatment in the form of background color is composed of (A without colors (control, (B white, (C in black, and (D red. Each treatment was repeated three times with a 45-day long research. Container maintenance in the form of an aquarium measuring 14x14x14 cm3 volume of 1 l and equipped with aeration. The prawns used were 10 fish / aquarium with a weighted average of 0.018 ± 0.21 g and the total length of the average of 0.82 ± 0.21 cm. Feeding in the form of an ad bloodworm satiation and include aquatic plant Hydrilla sp. as a source of additional food and shelter in the form of detritus. The results showed that the weight gain and the highest long background color was achieved by treatment D (red which is equal to 0.09 ± 0.3 g and 1.62 ± 0.3 cm. Survival at each treatment reached 100%. The water quality of all treatments during the study period remained within normal limits.

  6. Anaerobic decomposition of a native and an exotic submersed macrophyte in two tropical reservoirs

    Directory of Open Access Journals (Sweden)

    WA Chiba de Castro

    Full Text Available Some aquatic plants have fast metabolism and growth, even at sub-optimal conditions, and become dominant in lentic environments such as large reservoirs, altering the nutrient cycle and impairing their environmental quality. There is great need in the knowledge impact processes of invasive species in aquatic environments, among the major, those related to the decomposition. This study evaluated the anaerobic decomposition of invasive submerged macrophytes Egeria densa Planch, native, and Hydrilla verticillata (L.f. Royle, exotic in Porto Primavera and Jupiá reservoirs, Paraná basin. We evaluated the decay of organic matter, humification degree of the leached material, electrical conductivity and pH of the decomposition process. Mathematical models were utilised to describe the decomposition patterns over time. Both species showed the same heterogeneous pattern of decay of organic matter and carbon mineralisation. The models of carbon mineralisation, compared with the experimentally obtained data presented were adequate. Both species show no significant differences in the decomposition processes. Incubations of both species presented rapid t ½ for POC mineralisation and low DOC mineralisation.

  7. Concentrations of heavy metals and aquatic macrophytes of Govind Ballabh Pant Sagar an anthropogenic lake affected by coal mining effluent.

    Science.gov (United States)

    Mishra, Virendra Kumar; Upadhyay, Alka Rani; Pandey, Sudhir Kumar; Tripathi, B D

    2008-06-01

    Five heavy metals Cu, Cd, Mn, Pb and Hg were found in high concentration from three sampling sites located in Asia's largest anthropogenic lake Govind Ballabh Pant GBP Sagar. Concentrations of these heavy metals were measured in Water, bottom sediment and in different parts of the aquatic macrophytes collected from the reservoir. Plants collected from the lake were Eichhornia crassipes, Azolla pinnata, Lemna minor, Spirodela polyrrhiza, Potamogeton pectinatus, Marsilea quadrifolia, Pistia stratiotes, Ipomea aquqtica, Potamogeton crispus, Hydrilla verticillata and Aponogeton natans. These plants have shown the high concentrations of Cu, Cd, Mn, Pb and Hg in their different parts due to bioaccumulation. In general plant roots exhibited higher concentrations of heavy metals than corresponding sediments. A comparison between different morphological tissues of the sampled plants revealed the metal concentration in following order roots > leaves. Analyses of bottom sediment indicated the higher concentrations of Cd, Mn, Cu and Pb. Strong positive correlations were obtained between the metals in water and in plants as well as between metal in sediment and in plants. Indicating the potential of these plants for pollution monitoring of these metals.

  8. Heavy metals in water, sediments and wetland plants in an aquatic ecosystem of tropical industrial region, India.

    Science.gov (United States)

    Rai, Prabhat Kumar

    2009-11-01

    Concentrations of heavy metals (Cu, Cr, Fe, Pb, Zn, Hg, Ni, and Cd) and macronutrients (Mn) were measured in industrial effluents, water, bottom sediments, and wetland plants from a reservoir, Govind Ballabh (G.B.) Pant Sagar, in Singrauli Industrial region, India. The discharge point of a thermal power plant, a coal mine, and chlor-alkali effluent into the G.B. Pant Sagar were selected as sampling sites with one reference site in order to compare the findings. The concentrations of heavy metals in filtered water, sieved sediment samples (0.4-63 microm), and wetland plants were determined with particle-induced X-ray emission. The collected plants were Aponogeton natans, L. Engl. & Krause, Cyperus rotundus, L., Hydrilla verticillata, (L.f.) Royle, Ipomoea aquatica, Forssk., Marsilea quadrifolia, L., Potamogeton pectinatus, L., Eichhornia crassipes, (Mart.) Solms Monogr., Lemna minor, L., Spirodela polyrhiza (L.) Schleid. Linnaea, Azolla pinnata, R.Br., Vallisneria spiralis, L., and Polygonum amphibium, L. In general, metal concentration showed a significant positive correlation between industrial effluent, lake water, and lake sediment (p macrophytes for pollution monitoring.

  9. Bacterial community variation and microbial mechanism of triclosan (TCS) removal by constructed wetlands with different types of plants.

    Science.gov (United States)

    Zhao, Congcong; Xie, HuiJun; Xu, Jingtao; Xu, Xiaoli; Zhang, Jian; Hu, Zhen; Liu, Cui; Liang, Shuang; Wang, Qian; Wang, Jingmin

    2015-02-01

    Triclosan (TCS) is a broad-spectrum synthetic antimicrobial agent that is toxic to microbes and other aquatic organisms. Constructed wetlands (CWs) are now popular in TCS removal. However, knowledge on the effects of TCS on the bacterial community and microbial removal mechanism in CWs is lacking. The effects of TCS (60 μg L(-1)) on bacterial communities in batch-loaded CWs with emergent (Typha angustifolia), submerged (Hydrilla verticillata), and floating plant (Salvinia natans) were analyzed by 454 pyrosequencing technology. After six periods of experiment, the TCS removal efficiencies were over 90% in CWs, and negative effects of TCS on bacterial community richness and diversity were observed. Moreover, plant species effect existed. Bacterial strains that contributed to TCS biodegradation in CWs were successfully identified. In TCS-treated T. angustifolia and H. verticillata CWs, beta-Proteobacteria increased by 16.63% and 18.20%, respectively. In TCS-treated S. natans CWs, delta- and gamma-Proteobacteria and Sphingobacteria increased by 9.36%, 19.49%, and 31.37%, respectively, and could relate to TCS biodegradation. TCS affected the development of certain bacteria, and eventually, the bacterial community structures in CWs. This research provided ecologically relevant information on bacterial community and microbial removal mechanism in CWs under TCS treatment. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Opportunities for Phytoremediation and Bioindication of Arsenic Contaminated Water Using a Submerged Aquatic Plant:Vallisneria natans (lour.) Hara.

    Science.gov (United States)

    Chen, Guoliang; Liu, Xingmei; Brookes, Philip C; Xu, Jianming

    2015-01-01

    The identification of plants with high arsenic hyperaccumulating efficiency from water is required to ensure the successful application of phytoremediation technology. Five dominant submerged plant species (Vallisneria natans (Lour.) Hara., Potamageton crispus L., Myriophyllum spicatum L., Ceratophyllum demersum L. and Hydrilla verticillata (L.f.) Royle) in China were used to determine their potential to remove As from contaminated water. V. natans had the highest accumulation of As among them. The characteristics of As accumulation, transformation and the effect of phosphate on As accumulation in V. natans were then further studied. The growth of V. natans was not inhibited even when the As concentration reached 2.0 mg L(-1). After 21 d of As treatment, the bioconcentration factor (BCF) reached 1300. The As concentration in the environment and exposure time are major factors controlling the As concentration in V. natans. After being absorbed, As(V) is efficiently reduced to As(III) in plants. The synthesis of non-enzymic antioxidants may play an important role under As stress and increase As detoxication. In addition, As(V) uptake by V. natans was negatively correlated with phosphate (P) uptake when P was sufficiently supplied. As(V) is probably taken up via P transporters in V. natans.

  11. Applicability of drinking water treatment residue for lake restoration in relation to metal/metalloid risk assessment

    Science.gov (United States)

    Yuan, Nannan; Wang, Changhui; Pei, Yuansheng; Jiang, Helong

    2016-12-01

    Drinking water treatment residue (DWTR), a byproduct generated during potable water production, exhibits a high potential for recycling to control eutrophication. However, this beneficial recycling is hampered by unclear metal/metalloid pollution risks related to DWTR. In this study, the pollution risks of Al, As, Ba, Be, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, and Zn due to DWTR application were first evaluated for lake water based on human health risk assessment models and comparison of regulatory standards. The risks of DWTR were also evaluated for sediments on the basis of toxicity characteristics leaching procedure and fractionation in relation to risk assessment code. Variations in the biological behaviors of metal/metalloid in sediments caused by DWTR were assessed using Chironomus plumosus larvae and Hydrilla verticillata. Kinetic luminescent bacteria test (using Aliivibrio fischeri) was conducted to analyze the possibility of acute and chronic detrimental effects of sediment with DWTR application. According to the obtained results, we identify a potential undesirable effect of DWTR related to Fe and Mn (typically under anaerobic conditions); roughly present a dosage threshold calculation model; and recommend a procedure for DWTR prescreening to ensure safe application. Overall, managed DWTR application is necessary for successful eutrophication control.

  12. Enhancement of nitrate removal at the sediment-water interface by carbon addition plus vertical mixing.

    Science.gov (United States)

    Chen, Xuechu; He, Shengbing; Zhang, Yueping; Huang, Xiaobo; Huang, Yingying; Chen, Danyue; Huang, Xiaochen; Tang, Jianwu

    2015-10-01

    Wetlands and ponds are frequently used to remove nitrate from effluents or runoffs. However, the efficiency of this approach is limited. Based on the assumption that introducing vertical mixing to water column plus carbon addition would benefit the diffusion across the sediment-water interface, we conducted simulation experiments to identify a method for enhancing nitrate removal. The results suggested that the sediment-water interface has a great potential for nitrate removal, and the potential can be activated after several days of acclimation. Adding additional carbon plus mixing significantly increases the nitrate removal capacity, and the removal of total nitrogen (TN) and nitrate-nitrogen (NO3(-)-N) is well fitted to a first-order reaction model. Adding Hydrilla verticillata debris as a carbon source increased nitrate removal, whereas adding Eichhornia crassipe decreased it. Adding ethanol plus mixing greatly improved the removal performance, with the removal rate of NO3(-)-N and TN reaching 15.0-16.5 g m(-2) d(-1). The feasibility of this enhancement method was further confirmed with a wetland microcosm, and the NO3(-)-N removal rate maintained at 10.0-12.0 g m(-2) d(-1) at a hydraulic loading rate of 0.5 m d(-1).

  13. Permanent Genetic Resources added to Molecular Ecology Resources Database 1 May 2009-31 July 2009.

    Science.gov (United States)

    Almany, Glenn R; DE Arruda, Maurício P; Arthofer, Wolfgang; Atallah, Z K; Beissinger, Steven R; Berumen, Michael L; Bogdanowicz, S M; Brown, S D; Bruford, Michael W; Burdine, C; Busch, Jeremiah W; Campbell, Nathan R; Carey, D; Carstens, Bryan C; Chu, K H; Cubeta, Marc A; Cuda, J P; Cui, Zhaoxia; Datnoff, L E; Dávila, J A; Davis, Emily S; Davis, R M; Diekmann, Onno E; Eizirik, Eduardo; Fargallo, J A; Fernandes, Fabiano; Fukuda, Hideo; Gale, L R; Gallagher, Elizabeth; Gao, Yongqiang; Girard, Philippe; Godhe, Anna; Gonçalves, Evonnildo C; Gouveia, Licinia; Grajczyk, Amber M; Grose, M J; Gu, Zhifeng; Halldén, Christer; Härnström, Karolina; Hemmingsen, Amanda H; Holmes, Gerald; Huang, C H; Huang, Chuan-Chin; Hudman, S P; Jones, Geoffrey P; Kanetis, Loukas; Karunasagar, Iddya; Karunasagar, Indrani; Keyghobadi, Nusha; Klosterman, S J; Klug, Page E; Koch, J; Koopman, Margaret M; Köppler, Kirsten; Koshimizu, Eriko; Krumböck, Susanne; Kubisiak, T; Landis, J B; Lasta, Mario L; Lee, Chow-Yang; Li, Qianqian; Li, Shou-Hsien; Lin, Rong-Chien; Liu, M; Liu, Na; Liu, W C; Liu, Yuan; Loiseau, A; Luan, Weisha; Maruthachalam, K K; McCormick, Helen M; Mellick, Rohan; Monnahan, P J; Morielle-Versute, Eliana; Murray, Tomás E; Narum, Shawn R; Neufeld, Katie; De Nova, P J G; Ojiambo, Peter S; Okamoto, Nobuaki; Othman, Ahmad Sofiman; Overholt, W A; Pardini, Renata; Paterson, Ian G; Patty, Olivia A; Paxton, Robert J; Planes, Serge; Porter, Carolyn; Pratchett, Morgan S; Püttker, Thomas; Rasic, Gordana; Rasool, Bilal; Rey, O; Riegler, Markus; Riehl, C; Roberts, John M K; Roberts, P D; Rochel, Elisabeth; Roe, Kevin J; Rossetto, Maurizio; Ruzzante, Daniel E; Sakamoto, Takashi; Saravanan, V; Sarturi, Cladinara Roberts; Schmidt, Anke; Schneider, Maria Paula Cruz; Schuler, Hannes; Serb, Jeanne M; Serrão, Ester T A; Shi, Yaohua; Silva, Artur; Sin, Y W; Sommer, Simone; Stauffer, Christian; Strüssmann, Carlos Augusto; Subbarao, K V; Syms, Craig; Tan, Feng; Tejedor, Eugenio Daniel; Thorrold, Simon R; Trigiano, Robert N; Trucco, María I; Tsuchiya-Jerep, Mirian Tieko Nunes; Vergara, P; Van De Vliet, Mirjam S; Wadl, Phillip A; Wang, Aimin; Wang, Hongxia; Wang, R X; Wang, Xinwang; Wang, Yan; Weeks, Andrew R; Wei, Fuwen; Werner, William J; Wiley, E O; Williams, D A; Wilkins, Richard J; Wisely, Samantha M; With, Kimberly A; Wu, Danhua; Yao, Cheng-Te; Yau, Cynthia; Yeap, Beng-Keok; Zhai, Bao-Ping; Zhan, Xiangjiang; Zhang, Guo-Yan; Zhang, S Y; Zhao, Ru; Zhu, Lifeng

    2009-11-01

    This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Alcippe morrisonia morrisonia, Bashania fangiana, Bashania fargesii, Chaetodon vagabundus, Colletes floralis, Coluber constrictor flaviventris, Coptotermes gestroi, Crotophaga major, Cyprinella lutrensis, Danaus plexippus, Fagus grandifolia, Falco tinnunculus, Fletcherimyia fletcheri, Hydrilla verticillata, Laterallus jamaicensis coturniculus, Leavenworthia alabamica, Marmosops incanus, Miichthys miiuy, Nasua nasua, Noturus exilis, Odontesthes bonariensis, Quadrula fragosa, Pinctada maxima, Pseudaletia separata, Pseudoperonospora cubensis, Podocarpus elatus, Portunus trituberculatus, Rhagoletis cerasi, Rhinella schneideri, Sarracenia alata, Skeletonema marinoi, Sminthurus viridis, Syngnathus abaster, Uroteuthis (Photololigo) chinensis, Verticillium dahliae, Wasmannia auropunctata, and Zygochlamys patagonica. These loci were cross-tested on the following species: Chaetodon baronessa, Falco columbarius, Falco eleonorae, Falco naumanni, Falco peregrinus, Falco subbuteo, Didelphis aurita, Gracilinanus microtarsus, Marmosops paulensis, Monodelphis Americana, Odontesthes hatcheri, Podocarpus grayi, Podocarpus lawrencei, Podocarpus smithii, Portunus pelagicus, Syngnathus acus, Syngnathus typhle,Uroteuthis (Photololigo) edulis, Uroteuthis (Photololigo) duvauceli and Verticillium albo-atrum. This article also documents the addition of nine sequencing primer pairs and sixteen allele specific primers or probes for Oncorhynchus mykiss and Oncorhynchus tshawytscha; these primers and assays were cross-tested in both species.

  14. Biosorption and growth inhibition of wetland plants in water contaminated with a mixture of arsenic and heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soyoung [Department of Ocean Engineering, Pukyong National University, Busan (Korea, Republic of); Kang, Daeseok; Kim, Youngyun; Lee, Suk Mo; Chung, Yonghyun; Sung, Kijune [Department of Ecological Engineering, Pukyong National University, Busan (Korea, Republic of)

    2011-02-15

    The potential of wetland plants as an onsite biosorbent and a biomonitor for combined pollution of arsenic and four heavy metals from non-point sources was investigated in this study. Ceratophyllum demersum, Hydrilla verticillata, Hydrocharis dubia, and Salvinia natans were exposed to a water containing mixture of As, Cr, Cu, Pb, and Zn. Growth inhibition and biosorption potential of the wetland plants in artificially contaminated conditions were studied. These contaminants significantly reduced the growth of the plants. The tested wetland plants accumulated appreciable amounts of the contaminants in the following order: Pb>Cr>Cu>Zn>As. H. verticillata showed distinct visual change and a high biosorption factor (BSF) rank for As and heavy metals among the plants used in the study. As an unspecific collector of contaminants, it might be useful as a biomonitor and biosorbent in the As and heavy metal-contaminated aquatic system. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Mesohaline submerged aquatic vegetation survey along the U.S. gulf of Mexico coast, 2001 and 2002: A salinity gradient approach

    Science.gov (United States)

    Merino, J.H.; Carter, J.; Merino, S.L.

    2009-01-01

    Distribution of marine submerged aquatic vegetation (SAV; i.e., seagrass) in the northern Gulf of Mexico coast has been documented, but there are nonmarine submersed or SAV species occurring in estuarine salinities that have not been extensively reported. We sampled 276 SAV beds along the gulf coast in Florida, Alabama, Mississippi, Louisiana, and Texas in 2001 and 2002 in oligohaline to polyhaline (0 to 36 parts per thousand) waters to determine estuarine SAV species distribution and identify mesohaline SAV communities. A total of 20 SAV and algal species was identified and habitat characteristics such as salinity, water depth, pH, conductivity, turbidity, dissolved oxygen, and sediment composition were collected. Fourteen SAV species occurred two or more times in our samples. The most frequently occurring species was Ruppia maritima L. (n = 148), occurring in over half of SAV beds sampled. Eleocharis sp. (n = 47), characterized with an emergent rather than submerged growth form, was a common genus in the SAV beds sampled. A common marine species was Halodule wrightii Asch. (n = 36). Nonindigenous species Myriophyllum spicatum L. (n = 31) and Hydrilla verticillata (L. f.) Royle (n = 6) were present only in oligohaline water. Analyzing species occurrence and environmental characteristics using canonical correspondence and two-way indicator species analysis, we identify five species assemblages distinguished primarily by salinity and depth. Our survey increases awareness of nonmarine SAV as a natural resource in the gulf, and provides baseline data for future research. ?? 2009 by the Marine Environmental Sciences Consortium of Alabama.

  16. Evaluation of the Environmental DNA Method for Estimating Distribution and Biomass of Submerged Aquatic Plants.

    Science.gov (United States)

    Matsuhashi, Saeko; Doi, Hideyuki; Fujiwara, Ayaka; Watanabe, Sonoko; Minamoto, Toshifumi

    2016-01-01

    The environmental DNA (eDNA) method has increasingly been recognized as a powerful tool for monitoring aquatic animal species; however, its application for monitoring aquatic plants is limited. To evaluate eDNA analysis for estimating the distribution of aquatic plants, we compared its estimated distributions with eDNA analysis, visual observation, and past distribution records for the submerged species Hydrilla verticillata. Moreover, we conducted aquarium experiments using H. verticillata and Egeria densa and analyzed the relationships between eDNA concentrations and plant biomass to investigate the potential for biomass estimation. The occurrences estimated by eDNA analysis closely corresponded to past distribution records, and eDNA detections were more frequent than visual observations, indicating that the method is potentially more sensitive. The results of the aquarium experiments showed a positive relationship between plant biomass and eDNA concentration; however, the relationship was not always significant. The eDNA concentration peaked within three days of the start of the experiment in most cases, suggesting that plants do not release constant amounts of DNA. These results showed that eDNA analysis can be used for distribution surveys, and has the potential to estimate the biomass of aquatic plants.

  17. Chromium accumulation in submerged aquatic plants treated with tannery effluent at Kanpur, India.

    Science.gov (United States)

    Gupta, Kiran; Gaumat, Sumati; Mishra, Kumkum

    2011-09-01

    Aquatic macrophytes have been widely studied because of their capability of absorbing contaminants from water and their subsequent use in biomonitoring. This study presents a comparison of Cr accumulating potential of submerged aquatic plants viz Vallisneria spiralis and Hydrilla verticillata. These plants were treated with various concentrations of treated tannery effluent collected from UASB, Jajmau, Kanpur under repeated exposure in controlled laboratory conditions in order to assess their maximum bioaccumulation potential. The maximum accumulation of 385.6 and 201.6 microg g(-1) dry weight was found in roots of V. spiralis and the whole plants of H. verticillata, respectively at 100% concentration after 9th day of effluent exposure. The chlorophyll and protein content of both species decreased with increase in effluent concentration and duration. At highest concentration and duration a maximum reduction of 67.4 and 62.66% in total chlorophyll content, 9.97 and 4.66% in carotenoid content and 62.66 and 59.36% in protein content was found in V. spiralis and H. verticillata respectively. Anatomical studies in both V. spiralis and H. verticillata was carried out to assess the effects of metal accumulation within the plants. Changes in the anatomical structures of both plants exhibits the capacity of these species to act as indicator of effluent toxicity. The high accumulation potential of Cr by both plants revealed their capability to remove pollutants from effluent.

  18. Accumulation of microcystin congeners in different aquatic plants and crops--a case study from lake Amatitlán, Guatemala.

    Science.gov (United States)

    Romero-Oliva, Claudia Suseth; Contardo-Jara, Valeska; Block, Tobias; Pflugmacher, Stephan

    2014-04-01

    Microcystins (MCs) fate in natural environments can lead to its transfer into aquatic organisms, e.g. aquatic plants. Moreover, lakes in several countries sustain agriculture activities posing a serious health threat for the public. The case of Lake Amatitlán in Guatemala, was addressed to better understand MCs accumulation of four aquatic plants (Polygonum portoricensis, Eichhornia crassipes, Typha sp. and Hydrilla verticillata) coexisting with Microcystis aeruginosa blooms. These findings were further corroborated with an uptake/accumulation laboratory study. Finally crop products (Solanum lycopersicum and Capsicum annuum) irrigated with lake water were also evaluated for MCs. The obtained results suggest that Lake Amatitlán is highly contaminated with MCs (intra- and extracellular 1931 and 90 µg/L, respectively). In fruits of S. lycopersicum and C. annuum a concentration of 1.16 and 1.03 µg/kg dry weight (DW), respectively could be detected. All four aquatic plants showed a high MCs uptake capacity based on obtained bioconcentration factors (BCF) 165, 18, 16 and 11, respectively. These results were further corroborated in a laboratory study with 30 percent of total MCs taken up by H. verticillata within just 7 days. Additionally it was evidenced that all plants accumulated more MC-LR than other MCs congeners. Monitoring of crop products irrigated with lake water needs further consideration.

  19. Habitat selection by three littoral zone fishes: effects of predation pressure, plant density and macrophyte type

    Science.gov (United States)

    Chick, J.H.; McIvor, C.C.

    1997-01-01

    We conducted laboratory experiments which demonstrated that three littoral zone fishes differentially selected among three macrophytes when seeking refuge from predation. In the presence of a predator (a juvenile Micropterus salmoides), mosquitofish (Gambusia holbrooki), sailfin mollies (Poecilia latipinna). and dollar sunfish (Lepomis marginatus) displayed ferential use of four tank areas containing patches of either Hydrilla verticillata, Potamogeton illinoensis, Panicum hemitomon, or no plants. Patterns habitat selection, and the consistency of these patterns among replicates, differed among the three fishes and among three plant-density treatments - natural (each macrophyte presented at its mean field density), equal (all three macrophytes at the same density), and control (no plants). Selection for H. verticillata by mosquitofish was significant for both the equal and natural treatments, and thus was not caused by differences in plant density alone. Sailfin mollies displayed significant selection for H. verticillata only in the natural plant-density treatments. Dollar sunfish showed less consistent habitat selection than either mosquitofish or sailfin mollies. Significant habitat selection was not found in the absence of a predator, and there was no evidence for lection among the tank areas in control treatments. Patterns of habitat selection by the three fishes in our laboratory study corresponded to observed habitat use in Lake Okeechobee.

  20. Aquatic Food Plants and their Consumer Birds at Sandi Bird Sanctuary, Hardoi, Northern India

    Directory of Open Access Journals (Sweden)

    Kaushalendra Kumar Jha

    2013-07-01

    Full Text Available One of the Bird Sanctuaries of Uttar Pradesh, Sandi, was selected for studying some ecological aspects like, aquatic food plants, their food calendar and dependent birds of migratory as well as resident origin. The study site is considered as an ideal wetland. This is located at 27o15’ N and 79o55’ E. Thirty four food plant species were identified to be eaten by 16 birds.These plants were the species of Alloteropsis, Arundo, Azolla, Ceratophyllum, Chloris, Commelina, Cyperus, Echinochloa, Eichhornia, Eleocharis, Hydrilla, Ipomoea, Jussiaea, Lemna, Najas, Nelumbo, Nymphea, Nymphoides, Oryza, Pistia, Polygonum, Potamogeton, Scirpus, Spirodela, Trapa, Typha, Vallisneria, and Wolffia. Common consumer birds eating plant parts were Coot, Pochards, Teal, Wigeon, Gadwal, Gargany, Goose, Whistling-duck, Mallard, Pintail, Shoveler, and Swamphen. These are primarily the migratory birds except Coot, Whistling-duck and Swamphen. Spot-billed Duck, and Indian Moorhen were occasionally seen eating submerged hydrophytes and filamentous slimy green algae. On the basis of multi-strata growth of plants in the Sanctuary a wetland profile was prepared. Food calendar i.e., availability of palatable parts of plants during different months was recorded. Information collected in the study could be used for habitat management, especially the weed removal and ensuring food sustainability for the vegetarian birds.

  1. Fish abundances in shoreline habitats and submerged aquatic vegetation in a tidal freshwater embayment of the Potomac River.

    Science.gov (United States)

    Kraus, Richard T; Jones, R Christian

    2012-05-01

    Submerged aquatic vegetation (SAV) is considered an important habitat for juvenile and small forage fish species, but many long-term recruitment surveys do not effectively monitor fish communities in SAV. To better understand the impact of recent large increases of SAV on the fish community in tidal freshwater reaches of the Potomac River, we compared traditional seine sampling from shore with drop ring sampling of SAV beds (primarily Hydrilla) in a shallow water (depths, shoreline and SAV habitats in late summer of three different years (2007, 2008, and 2009). For the dominant species (Fundulus diaphanus, Lepomis macrochirus, Etheostoma olmstedi, Morone americana, Lepomis gibbosus, and Fundulus heteroclitus), density was nearly always higher in SAV, but overall, species richness was highest in shoreline habitats sampled with seines. Although historical monitoring of fish in Gunston Cove (and throughout Chesapeake Bay) is based upon seine sampling (and trawl sampling in deeper areas), the high densities of fish and larger areal extent of SAV indicated that complementary sampling of SAV habitats would produce more accurate trends in abundances of common species. Because drop ring samples cover much less area than seines and may miss rare species, a combination of methods that includes seine sampling is needed for biodiversity assessment. The resurgence of SAV in tidal freshwater signifies improving water quality, and methods we evaluated here support improved inferences about population trends and fish community structure as indicators of ecosystem condition.

  2. Dark/light modulation of ribulose bisphosphate carboxylase activity in plants from different photosynthetic categories

    Energy Technology Data Exchange (ETDEWEB)

    Vu, J.C.V.; Allen, L.H. Jr.; Bowes, G.

    1984-11-01

    Ribulose bisphosphate carboxylase/oxygenase (RuBPCase) from several plants had substantially greater activity in extracts from light-exposed leaves than dark leaves, even when the extracts were incubated in vitro with saturating HCO/sub 3//sup -/ and Mg/sup 2 +/ concentrations. This occurred in Glycine max, Lycopersicon esculentum, Nicotiana tabacum, Panicum bisulcatum, and P. hylaeicum (C/sub 3/); P. maximum (C/sub 4/ phosphoenolpyruvate carboxykinase); P. milioides (C/sub 3//C/sub 4/); and Bromelia pinguin and Ananas comosus (Crassulacean acid metabolism). Little or no difference between light and dark leaf extracts of RuBPCase was observed in Triticum aestivum (C/sub 3/); P. miliaceum (C/sub 4/ NAD malic enzyme); Zea mays and Sorghum bicolor (C/sub 4/ NADP malic enzyme); Moricandia arvensis (C/sub 3//C/sub 4/); and Hydrilla verticillata (submersed aquatic macrophyte). It is concluded that, in many plants, especially Crassulacean acid metabolism and C/sub 3/ species, a large fraction of ribulose-1,5-bisphosphate carboxylase/oxygenase in the dark is in an inactivatable state that cannot respond to CO/sub 2/ and Mg/sup 2 +/ activation, but which can be converted to an activatable state upon exposure of the leaf to light. 16 references, 2 tables.

  3. Effects of competitive interactions of different life forms submersed plants on biomass allocation in shallow lakes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiu-feng

    2010-01-01

    Plant competition has been recognized as one of the most important factors influencing the structure and function of lake ecosystems.Competition from plants of dissimilar growth form may have profound effects on shallow lakes.An experiment was conducted to investigate the effects of competitive interactions of submersed plants with dissimilar growth forms on the biomass allocations.Hydrilla verticillata and Vallisneria natans were selected and were planted in a single-species monoculture and a mixed-species pattern.Results showed that the growth of Ⅴ.natans was significantly affected by the H.verticillata and caused a sharp reduction of biomass,but the root:shoot ratio of Ⅴ.natans was not affected significantly and there was a minimal increase in mixture: while for H.verticillata,the biomass and the root:shoot ratio were not significantly changed by the competitive interactions of Ⅴ.natans,there was minimal increase qf biomass and minimal decrease of the root:shoot ratio.These results may indicate that the phant which candevelop a dense mat or canopy at the water surface would be a stronger competitor relative to the plant that dependsmore on light availability near the sediment.

  4. Dark/Light Modulation of Ribulose Bisphosphate Carboxylase Activity in Plants from Different Photosynthetic Categories 1

    Science.gov (United States)

    Vu, J. Cu V.; Allen, Leon H.; Bowes, George

    1984-01-01

    Ribulose bisphosphate carboxylase/oxygenase (RuBPCase) from several plants had substantially greater activity in extracts from lightexposed leaves than dark leaves, even when the extracts were incubated in vitro with saturating HCO3− and Mg2+ concentrations. This occurred in Glycine max, Lycopersicon esculentum, Nicotiana tabacum, Panicum bisulcatum, and P. hylaeicum (C3); P. maximum (C4 phosphoenolpyruvate carboxykinase); P. milioides (C3/C4); and Bromelia pinguin and Ananas comosus (Crassulacean acid metabolism). Little or no difference between light and dark leaf extracts of RuBPCase was observed in Triticum aestivum (C3); P. miliaceum (C4 NAD malic enzyme); Zea mays and Sorghum bicolor (C4 NADP malic enzyme); Moricandia arvensis (C3/C4); and Hydrilla verticillata (submersed aquatic macrophyte). It is concluded that, in many plants, especially Crassulacean acid metabolism and C3 species, a large fraction of ribulose-1,5-bisphosphate carboxylase/oxygenase in the dark is in an inactivatable state that cannot respond to CO2 and Mg2+ activation, but which can be converted to an activatable state upon exposure of the leaf to light. PMID:16663937

  5. Dark/Light modulation of ribulose bisphosphate carboxylase activity in plants from different photosynthetic categories.

    Science.gov (United States)

    Vu, J C; Allen, L H; Bowes, G

    1984-11-01

    Ribulose bisphosphate carboxylase/oxygenase (RuBPCase) from several plants had substantially greater activity in extracts from lightexposed leaves than dark leaves, even when the extracts were incubated in vitro with saturating HCO(3) (-) and Mg(2+) concentrations. This occurred in Glycine max, Lycopersicon esculentum, Nicotiana tabacum, Panicum bisulcatum, and P. hylaeicum (C(3)); P. maximum (C(4) phosphoenolpyruvate carboxykinase); P. milioides (C(3)/C(4)); and Bromelia pinguin and Ananas comosus (Crassulacean acid metabolism). Little or no difference between light and dark leaf extracts of RuBPCase was observed in Triticum aestivum (C(3)); P. miliaceum (C(4) NAD malic enzyme); Zea mays and Sorghum bicolor (C(4) NADP malic enzyme); Moricandia arvensis (C(3)/C(4)); and Hydrilla verticillata (submersed aquatic macrophyte). It is concluded that, in many plants, especially Crassulacean acid metabolism and C(3) species, a large fraction of ribulose-1,5-bisphosphate carboxylase/oxygenase in the dark is in an inactivatable state that cannot respond to CO(2) and Mg(2+) activation, but which can be converted to an activatable state upon exposure of the leaf to light.

  6. Screening of native plants and algae growing on fly-ash affected areas near National Thermal Power Corporation, Tanda, Uttar Pradesh, India for accumulation of toxic heavy metals.

    Science.gov (United States)

    Dwivedi, S; Srivastava, S; Mishra, S; Dixit, B; Kumar, A; Tripathi, R D

    2008-10-30

    The present investigation was carried out to screen native plants growing in fly-ash (FA) contaminated areas near National Thermal Power Corporation, Tanda, Uttar Pradesh, India with a view to using them for the eco-restoration of the area. A total number of 17 plants (9 aquatic, 6 terrestrial and 2 algal species) were collected and screened for heavy metal (Fe, Zn, Cu, Mo, B, Si, Al, Cr, Pb, Cd, Hg and As) accumulation. Differential accumulation of various heavy metals by different species of plants was observed. Hydrilla verticillata was found to be the most efficient metal accumulator among 9 aquatic plants, Eclipta alba among 6 terrestrial plants and Phormedium papyraceum between 2 algal species. In general, the maximum levels of most metals were found in terrestrial plants while the lowest in algal species. However, translocation of the metals from root to shoot was found to be higher in aquatic plants than terrestrial ones. These results suggest that various aquatic, terrestrial and algal species of plants may be used in a synergistic way to remediate and restore the FA contaminated areas.

  7. Vegetative Propagule Pressure and Water Depth Affect Biomass and Evenness of Submerged Macrophyte Communities.

    Science.gov (United States)

    Li, Hong-Li; Wang, Yong-Yang; Zhang, Qian; Wang, Pu; Zhang, Ming-Xiang; Yu, Fei-Hai

    2015-01-01

    Vegetative propagule pressure may affect the establishment and structure of aquatic plant communities that are commonly dominated by plants capable of clonal growth. We experimentally constructed aquatic communities consisting of four submerged macrophytes (Hydrilla verticillata, Ceratophyllum demersum, Elodea nuttallii and Myriophyllum spicatum) with three levels of vegetative propagule pressure (4, 8 and 16 shoot fragments for communities in each pot) and two levels of water depth (30 cm and 70 cm). Increasing vegetative propagule pressure and decreasing water level significantly increased the growth of the submerged macrophyte communities, suggesting that propagule pressure and water depth should be considered when utilizing vegetative propagules to re-establish submerged macrophyte communities in degraded aquatic ecosystems. However, increasing vegetative propagule pressure and decreasing water level significantly decreased evenness of the submerged macrophyte communities because they markedly increased the dominance of H. verticillata and E. nuttallii, but had little impact on that of C. demersum and M. spicatum. Thus, effects of vegetative propagule pressure and water depth are species-specific and increasing vegetative propagule pressure under lower water level can facilitate the establishment success of submerged macrophyte communities.

  8. Correlation between pollen morphology and pollination mechanisms in the Hydrocharitaceae.

    Science.gov (United States)

    Tanaka, Norio; Uehara, Koichi; Murata, Jin

    2004-08-01

    The pollen morphology of 11 genera and 11 species of the Hydrocharitaceae and one species of the Najadaceae was studied using scanning and transmission electron microscopies, and the exine structures and sculptures are discussed in relation to pollination mechanisms and the molecular phylogeny. The pollen grains of the Hydrocharitaceae are spherical, inaperturate, and form monads or tetrads, while those of the Najadaceae are elliptical, inaperturate, and form monads. The entomophilous genera Egeria, Blyxa, Ottelia, Stratiotes, and Hydrocharis share pollen grains that have projections like spines or bacula. The anemophilous genus Limnobium has reticulate pollen grains. The hypohydrophilous genera Thalassia and Najas are characterized by pollen grains with reduced exine structures. The pollen-epihydrophilous genera Elodea and Hydrilla have tightly arranged small spinous pollen grains, and the male flower-epihydrophilous genera Enhalus and Vallisneria have reduced reticulate or gemmate exines. Character state reconstruction of the exine structures and sculptures using a molecular phylogenetic tree suggests that variation in the exine is generally correlated with the pollination mechanism; the selective pressures acting on the pollination mechanisms have reduced the exine structure in hypohydrophilous plants and resulted in various exine sculptures that are adapted to the different pollination mechanisms in entomophilous, anemophilous, and pollen-epihydrophilous plants.

  9. Epiphytic bacterial communities on two common submerged macrophytes in Taihu Lake: diversity and host-specificity

    Institute of Scientific and Technical Information of China (English)

    HE Dan; REN Lijuan; WU Qinglong

    2012-01-01

    Leaves of terrestrial and aquatic plants are home to a wide diversity of bacterial species.However,the diversity and variability of epiphytic bacteria on their submerged plant hosts remains poorly understood.We investigated the diversity and composition of epiphytic bacteria from two common submerged macrophytes:Vallisneria natans and Hydrilla verticillata in Taihu Lake,Jiangsu,China,using methods of terminal restriction fragment length polymorphisms (T-RFLP) and clone library analyses targeted at bacterial 16S rRNA genes.The results show that:(1) the libraries of the two waterweeds contain wide phylogenetic distribution of bacteria,and that the sequences of the two libraries can be separated into 93 OTUs (at 97% similar value); (2) Betaproteobacteria,including Burkholderiales,was the most abundant bacterial group on both plants.Cyanobacteria and Gammaproteobacteria were the second largest groups on V.natans and H.verticillata,respectively.Both clone libraries included some sequences related to those of methanotrophs and nitrogen-fixing bacteria; (3) Cluster analysis of the T-RFLP profiles showed two distinct clusters corresponding to the two plant populations.Both ANOSIM of the T-RFLPdata and Libshuff analysis of the two clone libraries indicated a significant difference in epiphytic bacterial communities between the two plants.Therefore,the epiphytic bacterial communities on submerged macrophytes appear to be diverse and host-specific,which may aid in understanding the ecological functions of submerged macrophytes in general.

  10. The gene CmACS-7 provides sequence variation for the development of DNA markers associated with monoecious sex expresion in melon (Cucumis melo L.)

    Science.gov (United States)

    Most melon (Cucumis melo L.) breeding lines in South Korea display andromonoecious sex expression (i.e., possessing both bisexual and male flowers on the same plant), which, in turn, necessitates laborious hand emasculation during F1 hybrid seed production. Thus, there is a need to develop monoecio...

  11. Acclimation to high CO/sub 2/ in monoecious cucumbers. II. Carbon exchange rates, enzyme activities, and starch and nutrient concentrations. [Cucumis sativus L

    Energy Technology Data Exchange (ETDEWEB)

    Peet, M.M.; Huber, S.C.; Patterson, D.T.

    1986-01-01

    Carbon exchange capacity of cucumber (Cucumis sativus L.) germinated and grown in controlled environment chambers at 1000 microliters per liter CO/sub 2/ decreased from the vegetative growth stage to the fruiting stage, during which time capacity of plants grown at 350 microliters per liter increased. Carbon exchange rates (CERs) measured under growth conditions during the fruiting period were, in fact, lower in plants grown at 1000 microliters per liter CO/sub 2/ than those grown at 350. Progressive decreases in CERs in 1000 microliters per liter plants were associated with decreasing stomatal conductances and activities of ribulose bisphosphate carboxylase and carbonic anhydrase. Leaf starch concentrations were higher in 1000 microliters per liter CO/sub 2/ grown-plants than in 350 microliters per liter grown plants but calcium and nitrogen concentrations were lower, the greatest difference occurring at flowering. Sucrose synthase and sucrose-P-synthase activities were similar in 1000 microliters per liter compared to 350 microliters per liter plants during vegetative growth and flowering but higher in 350 microliters per liter plants at fruiting. The decreased carbon exchange rates observed in this cultivar at 1000 microliters per liter CO/sub 2/ could explain the lack of any yield increase when compared with plants grown at 350 microliters per liter.

  12. Effects of submerged plants on growth performance and non-specific immunity of Chinese mitten crab (Eriocheir sinensis)%沉水植物对中华绒螯蟹生长和非特异性免疫力的影响

    Institute of Scientific and Technical Information of China (English)

    孙丽萍; 宋学宏; 朱金荣; 孟祥雨; 张磊磊

    2012-01-01

    从东太湖采集伊乐藻(Elodea canadensis)、金鱼藻(Ceratophyllum demersum)、轮叶黑藻(Hydrilla verticillata)、苦草(Vallisneria natans)、马来眼子菜(Potamogeton malaianus)5种沉水植物分别制成干粉.在基础饲料中添加15%的干粉形成5种不同的配合饲料,分别饲喂体重为(9.37±0.15)g的中华绒螯蟹(Eriocheir sinensis)60 d,分析沉水植物对中华绒螯蟹生长和非特异性免疫力的影响.结果显示:马来眼子菜组的中华绒螯蟹平均增重率显著低于对照组(P<0.05),饲料系数显著高于对照组(P<0.05),其余4种沉水植物组的平均增重率和饲料系数与对照组无显著差异(P>0.05);各组成活率、肥满度及肝体比差异不显著(P>0.05).沉水植物各组的蟹血清超氧化物歧化酶活力显著高于对照组(P<0.05);与对照组相比,轮叶黑藻组、伊乐藻组和苦草组的中华绒螯蟹血清溶菌酶活性显著升高(P<0.05),金鱼藻组和马来眼子菜组则差异不显著(P>0.05);除马来眼子菜组降低外,其余4种沉水植物组中华绒螯蟹对嗜水气单胞菌的抵抗力强于对照组.因此,除马来眼子菜以外的4种沉水植物对中华绒螯蟹的生长性能无明显的促进作用,但可在一定程度上提高其非特异性免疫力.%The five submerged plants, Elodea canadensis, Ceratophyllum demersum, Hydrilla verticillata, Vallisneria na-tans and Potamogeton malaianus, were collected in East Lake Taihu, and made into dry powders. The dry powders were then incorporated into a basal diet by 15% , respectively, to obtain 5 different mixed diets, and were used to feed Chinese mitten crab ( Eriocheir sinensis ) weighing ( 9. 37 ± 0. 15 ) g for 60 days. The effects of these submerged plants on growth performance and non-specific immunity of Chinese mitten crab were examined. The results showed that the average weight gain rate ( WGR) of Chinese mitten crab in P. Malaianus fed group was significantly lower than

  13. Studies on sustainability of simulated constructed wetland system for treatment of urban waste: Design and operation.

    Science.gov (United States)

    Upadhyay, A K; Bankoti, N S; Rai, U N

    2016-03-15

    New system configurations and wide range of treatability make constructed wetland (CW) as an eco-sustainable on-site approach of waste management. Keeping this view into consideration, a novel configured three-stage simulated CW was designed to study its performance efficiency and relative importance of plants and substrate in purification processes. Two species of submerged plant i.e., Potamogeton crispus and Hydrilla verticillata were selected for this study. After 6 months of establishment, operation and maintenance of simulated wetland, enhanced reduction in physicochemical parameters was observed, which was maximum in the planted CW. The percentage removal (%) of the pollutants in three-stage mesocosms was; conductivity (60.42%), TDS (67.27%), TSS (86.10%), BOD (87.81%), NO3-N (81.28%) and PO4-P (83.54%) at 72 h of retention time. Submerged macrophyte used in simulated wetlands showed a significant time dependent accumulation of toxic metals (p ≤ 0.05). P. crispus accumulated the highest Mn (86.36 μg g(-1) dw) in its tissue followed by Cr (54.16 μg g(-1) dw), Pb (31.56 μg g(-1) dw), Zn (28.06 μg g(-1) dw) and Cu (25.76 μg g(-1) dw), respectively. In the case of H. verticillata, it was Zn (45.29), Mn (42.64), Pb (22.62), Cu (18.09) and Cr (16.31 μg g(-1) dw). Thus, results suggest that the application of simulated CW tackles the water pollution problem more efficiently and could be exploited in small community level as alternative and cost effective tools of phytoremediation.

  14. Biomonitoring of selected freshwater macrophytes to assess lake trace element contamination: a case study of Nal Sarovar Bird Sanctuary, Gujarat, India

    Directory of Open Access Journals (Sweden)

    Rita N. KUMAR

    2006-02-01

    Full Text Available A biomonitoring study was carried out at Nal Sarovar Bird Sanctuary, a proposed Ramsar site, Gujarat State, India, to ascertain the degree of trace element contamination. The study focused on assessment of trace element contamination in certain aquatic macrophytes to be used as biomonitors, in comparison with the sediments (abiotic monitor for heavy metal pollution. Good information was provided by analyzing roots, stems and leaves of native aquatic plants (biomonitors represented by eight species: Bergia odorata, Hydrilla verticillata, Ipomoea aquatica, Najas graminea, Nelumbo nucifera, Phragmites karka, Typha angustata and Vellisnaria spiralis, alongwith surface sediments and water, were analyzed for Cd, Co, Cu, Cu, Ni, Pb and Zn contamination. The highest concentrations of the trace elements were measured in Ipomoea aquatica and the lowest in Bergia odorata. Based on the concentration and toxicity status observed in the lake's vegetation, the six metals are arranged in the following decreasing order: Zn > Cu > Ni > Co > Pb > Cd. Compared with the standard, normal and critical toxicity range in plants, the detected values of Cd and Pb falls within normal range, while that of Co, Ni and Cu were within the critical range. However, Zn showed the highest concentration and alarming toxicity levels, which is considered as one of the most hazardous pollutants in Nal Sarovar Bird Sanctuary. Certain aquatic macrophytes species are also proposed as biomonitors for the investigated heavy metal pollutants. Such result was significant in the plant species such as Ipomoea aquatica and Phragmites karka, which are the two most useful species in biomonitoring studies due to their ability to accumulate elements in high concentration in the roots and their availability throughout the year. The results showed the significant difference in accumulation rate of some metals like Zn, Cu and Ni in different plant organs, which showed more accumulation in root than

  15. Bioavailable phosphorus (P) reduction is less than mobile P immobilization in lake sediment for eutrophication control by inactivating agents.

    Science.gov (United States)

    Wang, Changhui; He, Rui; Wu, Yu; Lürling, Miquel; Cai, Haiyuan; Jiang, He-Long; Liu, Xin

    2017-02-01

    Phosphorus (P) immobilization by inactivating agents in the sediment of eutrophic lakes to reduce immediately available P in lake water is often crucial for mitigating nuisance eutrophication symptoms, such as cyanobacterial blooms. Macrophytes and phytoplankton, however, can directly utilize P from the sediment for growth. Accordingly, a comprehensive analysis of the P bioavailability in lake sediment amended with two promising P-inactivation agents, namely Phoslock(®) and drinking water treatment residue (DWTR), was investigated in both short- and long-term studies (20 and 180 d). Phosphorus-availability was assessed using six chemical extraction methods and Hydrilla verticillata and Microcystis aeruginosa growth tests. The results showed that Phoslock(®) and DWTR significantly reduced mobile P (NH4Cl and Na2S2O4/NaHCO3 extractable P) in lake sediment, while P bioavailability that was assessed by different methods showed considerable deviations. Interestingly, appropriate bioavailable P chemical extraction methods were determined based on linear correlation analysis, and further comparison indicated that reduction of bioavailable P by DWTR (P) and Phoslock(®) (P) were clearly less than the mobile P immobilization (>75%) at recommended dosages, which was probably caused by the capability of macrophyte and cyanobacteria to utilize various fractions of P (except the residual P) in amended sediment under proper illumination. Therefore, DWTR and Phoslock(®) can effectively reduce P release from lake sediment, but the potential bioavailable P may pose uncertainties for eutrophication control in lakes that typically have regular sediment re-suspension. Overall, an evaluation of the bioavailable P pool in the lake ecosystem should be essential for successful lake geo-engineering.

  16. Ecology of rare water plant communities in lakes of north-eastern Poland

    Directory of Open Access Journals (Sweden)

    Ewa Jabłońska

    2012-03-01

    Full Text Available Habitat studies were conducted on three rare plant communities dominated by Nuphar pumila, Nymphaea candida and Hydrilla verticillata in lakes of north-eastern Poland. The comparison of habitat properties of these three types of phytocoenoses with those of Nuphar lutea common in the area under study was also performed. It was demonstrated that the plant communities studied were ecologically distinct. The habitats of the phytocoenoses of N. pumila differed most significantly from those of the other phytocoenoses. They often inhabited softer waters poor in Mg2+, dissolved SiO2, but rich in total Fe, PO43−, NO3−, and were associated with acidic substrates containing lower levels of Ca2+ and Na+, but greater amounts of total Fe and NO3−. The differences in the habitats of H. verticillata and N. candida phytocoenoses were most pronounced in the case of four properties of water: Na+, K+, Cl−, and Mg+. Their values were lower in waters of the H. verticillata phytocoenoses. The habitats of all the three types of rare phytocoenoses differed considerably from those of N. lutea. The most significant differences were found between the N. lutea and N. pumila phytocoenoses and the smallest differences were between the patches of N. lutea and N. candida. The properties of water were more important in differentiating the habitats of the phytocoenoses studied than the substrate properties. Due to alkalization and increase in water hardness in the lakes studied the stands of N. pumila are among the most threatened. The patches of N. candida and H. verticillata, which occur in waters with a wider range of hardness and tolerating a slight increase in trophy, can still continue to persist in the lakes for a long time.

  17. Cultivation of macroscopic marine algae and freshwater aquatic weeds. Progress report, May 1-December 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Ryther, J. H.

    1979-01-01

    Studies were continued during 1977 to 1978 on the growth and yields in culture of the red seaweed Gracilaria tikvahiae. Partial control of epiphytes was achieved by nutrient removal, shading, and/or biological agents. For the first time, a single clone of the alga was grown continuously throughout the year without replacement. Yields in large (2600 1) aluminum tanks averaged 21.4 g dry weight/m/sup 2/.day, equivalent to 31 tons/acre.year (15.5 ash-free dry wt tons/acre.year). Growth of Gracilaria and other seaweeds in Vexar-mesh baskets in natural habitats and in the oceanic waters of a power plant cooling water intake canal were unsuccessful. Productivity of the freshwater macrophytes Lemna minor (common duckweed), Eichhornia crassipes (water hyacinth), and Hydrilla verticillata have now been measured throughout the year with mean yields of 3.7, 24.2 and 4.2 g dry weight/m/sup 2/.day (5.4, 35.3, and 6.1 dry tons/acre.year) respectively. Yields of duckweed and water hyacinths in the Harbor Branch Foundation culture units have averaged roughly three times those of the same species growing in highly-eutrophic natural environments. The yields of several other species of freshwater plants were investigated. Only the pennywort (Hydrocotyle umbellata) appears to approach the productivity of water hyacinth on the basis of preliminary measurements. Chopped water hyacinths and unprocessed Gracilaria have both been successfully fermented to methane in anaerobic digesters and the liquid digester residues recycled to produce more of the same plants.

  18. Cultivation of macroscopic marine algae and freshwater aquatic weeds. Progress report, May 1--December 31, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Ryther, J. H.

    1977-01-01

    Research was divided between basic physiological studies of the growth and nutrient-uptake kinetics of macroscopic marine algae and the more applied problems involved in the selection of species and the development of inexpensive, non-energy intensive culture methods for growing seaweeds and freshwater plants as a biomass source for conversion to energy. Best growth of the seaweeds occurs at low (0.1 to 1.0 ..mu..molar) concentration of major nutrients, with ammonia as a nitrogen source, with rapid exchange of the culture medium (residence time of 0.05 days or less). Of 43 species of seaweeds evaluated, representatives of the large red alga genus Gracilaria appear most promising with potential yields, in a highly intensive culture system under optimal conditions, of some 129 metric dry tons per hectare per year (about half of which is organic). Non-intensive culture methods have yielded one-third to one-half that figure. Unexplained periodicity of growth and overgrowth by epiphytes remain the most critical constraint to large-scale seaweed culture. Freshwater weed species in culture include water hyacinth (Eichhornia crassipes), duckweed (Lemna minor), and Hydrilla vertecillata, with yields to date averaging 15, 4, and 8 g dry wt/m/sup 2//day, respectively. However, these plants have not yet been grown through the winter, so average annual yields are expected to be lower. In contrast to the seaweeds, the freshwater plants grow well at high nutrient concentrations and slow culture volume exchange rates (residence time ca. 20 days or more). Experiments were initiated on the recycling of digester residues from the fermentation of the freshwater and marine plants as a possible nutrient source for growth of the same species.

  19. Assessment of Wetland Water Quality and Avian Diversity of a Human-Modified Floodplain Wetland on River Yamuna

    Directory of Open Access Journals (Sweden)

    Upma MANRAL

    2013-02-01

    Full Text Available Okhla Bird Sanctuary (OBS is an Important Bird Area, which comes under the protected area network of Uttar Pradesh with one-third area lying in the state of Delhi (India. OBS has widest flood plains along the Delhi stretch of river Yamuna and is important in conserving the ecological wealth of floodplains of the river. Rapid urbanization and industrialization and discharge of untreated wastewater into the river have resulted in deteriorated water quality. The present study focused on assessment of water quality, aquatic flora and avifaunal diversity in the OBS. Water quality was analyzed following methods of APHA. For vegetation analysis, sub-merged and free-floating plants were scooped up from five randomly selected sites. Total bird counts were conducted for water birds and species richness, evenness and Shannon-Weaver species diversity indices were calculated. Results indicate that the organic load is very high in the wetland as evident from low levels of dissolved oxygen (2.26 ± 1.62 mg/l and high Biological and Chemical Oxygen Demands (15.20 ± 3.75 mg/l, 44.60 ± 12.07 mg/l. Nine species of free-floating and submerged plants were recorded; Hydrilla verticillata, Vallisneria spiralis, Azolla pinnata and Ceratophyllum demersum dominated both deep and shallow water areas. 52 species of waterbirds including four near-threatened species viz., Anhinga melanogaster, Mycteria leucocephala, Threskiornis melanocephalus and Aythya nyroca were recorded. OBS provides opportunities for conservation in a metropolitan area, thus, appropriate measures should be taken to maintain its ecological integrity.

  20. Influences of chemical components of water extracts from submerged macrophyte leaves on the growth of three common epiphytic algae%沉水植物浸提液组分对三种常见附植藻类生长的影响

    Institute of Scientific and Technical Information of China (English)

    纪海婷; 谢冬; 周恒杰; 安树青

    2015-01-01

    采用长江中下游湖泊典型沉水植物乡土种轮叶黑藻(Hydrilla verticillata)、穗状狐尾藻(Myriophyllum spicatum)和外来种伊乐藻(Elodea nuttallii)、水盾草(Cabomba caroliniana)叶片浸提液的组分:N-苯基-2-萘胺(4种沉水植物均有)、苯丙酮(伊乐藻特有)和苯并呋喃(水盾草特有),研究不同物质种类及浓度对3种附植藻类:普通小球藻(Chlorella vulgaris)、斜生栅藻(Scenedesmus obliqnus)和四尾栅藻(S.quadricanda)的相对生长率、藻细胞浓度、叶绿素含量等生长指标的影响.结果表明:3种物质均显著降低斜生栅藻和普通小球藻的细胞浓度以及叶绿素含量,对四尾栅藻生长的抑制较弱.3种附植藻类生长指标对不同物质浓度及处理时间的响应存在显著差异,呈现低浓度促进、高浓度抑制现象,随时间推移藻类显示出明显的生长趋势.物质作用效果:苯丙酮>苯并呋喃>N-苯基-2-萘胺,表明外来种沉水植物叶片浸提液中特有物质具有较强的抑藻效应.

  1. Effects of leaf extracts from two kinds of submerged macrophytes on the growth and community composition of epiphytic algae living on native macrophyte species%两类沉水植物浸提液对乡土种叶附植藻类生长与群落组成的影响

    Institute of Scientific and Technical Information of China (English)

    纪海婷; 谢冬; 周恒杰; 安树青

    2013-01-01

    将外来种沉水植物伊乐藻(Elodea nuttallii)、聚叶狐尾藻(Myriophyllum aquaticum)分别与其同科(或同属)的乡土种沉水植物轮叶黑藻(Hydrilla verticillata)、穗状狐尾藻(Myriophyllum spicatum)进行对比,分析了两种乡土沉水植物叶表面附植藻类的群落组成与结构特征,采用植物浸提液法研究不同浓度(0.5和2 mg·mL-1)的叶片浸提液对乡土种叶附植藻类生长和群落组成的影响.结果表明:两种外来沉水植物较乡土种具有更强的抑藻效应,且在高浓度下更显著;4种沉水植物浸提液均降低乡土种叶附植藻类的细胞总数,对群落物种丰富度和多样性的影响总体呈“低浓度促进、高浓度抑制”,且外来种的抑制更显著,其浸提液使得附植藻类群落组成结构趋于简单化;植物鲜样制备的浸提液较植物干样制备的浸提液具有更强的化感抑藻作用.

  2. Do Amplitudes of Water Level Fluctuations Affect the Growth and Community Structure of Submerged Macrophytes?

    Science.gov (United States)

    Wang, Mo-Zhu; Liu, Zheng-Yuan; Luo, Fang-Li; Lei, Guang-Chun; Li, Hong-Li

    2016-01-01

    Submerged macrophytes are subjected to potential mechanical stresses associated with fluctuating water levels in natural conditions. However, few experimental studies have been conducted to further understand the effects of water level fluctuating amplitude on submerged macrophyte species and their assemblages or communities. We designed a controlled experiment to investigate the responses of three submerged macrophyte species (Hydrilla verticillata, Ceratophyllum demersum and Elodea nuttallii) and their combinations in communities to three amplitudes (static, ± 30 cm, ± 60 cm) of water level fluctuations. Results showed that water level fluctuating amplitude had little effects on the community performance and the three tested species responded differently. H. verticillata exhibited more growth in static water and it was negatively affected by either of the water level fluctuations amplitude, however, growth parameters of H. verticillata in two fluctuating water level treatments (i.e., ± 30 cm, ± 60 cm) were not significantly different. On the other hand, the growth of C. demersum was not significantly correlated with different amplitude treatments. However, it became more abundant when water levels fluctuated. E. nuttallii was inhibited by the two fluctuating water level treatments, and was less in growth parameters compared to the other species especially in water level fluctuating conditions. The inherent differences in the adaptive capabilities of the tested species indicate that C. demersum or other species with similar responses may be dominant species to restore submerged macrophyte communities with great fluctuating water levels. Otherwise, H. verticillata, E. nuttallii or other species with similar responses could be considered for constructing the community in static water conditions.

  3. The effects of Bellamya sp. on the growth of two submerged macrophytes in Lake Taihu%太湖环棱螺对两种常见沉水植物生长的影响

    Institute of Scientific and Technical Information of China (English)

    白秀玲; 谷孝鸿; 张钰

    2007-01-01

    环棱螺(Bellamya sp.)是太湖常见的一类软体动物.本研究通过室内实验,探讨环棱螺对轮叶黑藻(Hydrilla verticillata Royle)和伊乐藻(Elodea nuttalli ST John)生长的影响及水体营养盐含量的变化.结果表明,三种处理情况下,单位质量伊乐藻增加的数量分别为:H组0.475 g,L组0.106 g,C组0.021 g,单位质量轮叶黑藻增加的数量分别为:H组0.704 g,L组0.663 g,C组0.478 g.从实验前后两种沉水植物的长度和分蘖数变化来看,H组最高,L组与C组分别次之,所以不论生物量、长度还是分蘖数的变化量,与环棱螺共存的伊乐藻和轮叶黑藻的变化都高于对照组中两种沉水植物的变化.环棱螺新陈代谢促进水体中溶解态氮磷含量增加,三种情况下水生植物的初级生产力都相当,由此可推测环棱螺通过新陈代谢,一定程度上促进了两种沉水植物的生长.

  4. Influence of temperature on the growth and nutrient removal of five submerged macrophytes%温度对五种沉水植物生长和营养去除效果的影响

    Institute of Scientific and Technical Information of China (English)

    闫志强; 刘黾; 吴小业; 刘燕; 潘美婷; 王嘉华; 蔡丽桃; 李秋宇; 陈章和

    2014-01-01

    研究温度对黑藻(Hydrilla verticillata)、伊乐藻(Elodea canadensis)、狐尾藻(Myriophyllum spicatum)、苦草(Vallisneria spiralis)和竹叶眼子菜(Potamogeton malaianus)在霍格兰氏水培条件下的生长和营养去除效果的影响.结果表明:温度对五种沉水植物的生长有显著影响.除苦草的最适生长温度为30℃外,其余四种植物的最适生长温度为20℃.五种植物的生长速度有显著性差异,以伊乐藻、竹叶眼子菜、黑藻生长较快.对TP和CODcr的去除率随温度的升高而升高,对NH4-N的去除率除竹叶眼子菜外,呈单峰曲线,去除率最适温度为25℃.五种沉水植物对TP的去除率通常差异不显著;竹叶眼子菜对NH4-N去除率显著低于其他植物(p<0.05),而对CODcr的去除率显著高于其他植物(p<0.05).

  5. STUDY ON THE PHYSIOLOGY OF ENVIRONMENT POLLUTION AND THE EFFECT OF HEATING ON THE MALATHION RESIDUE ANALYZED USING THE RADIOTRACER METHOD

    Directory of Open Access Journals (Sweden)

    Razak Achmad Hamzah

    2011-04-01

    Full Text Available The aim of this study is to determine, the comparison of absorption by aquatic plants Hydrilla verticillata and Waterhyacinth (Eichhomia crassipes of malathion insecticide residues in water and comparison of malathion concentrationin tissues of fish fed with of contaminated water plants (Water hyacinth with tissues of fish, which was not fedcontaminated water plant. The effect of heating the contaminated fish tissue, on its level in tissues of rats that consumeit. For the first experiment (aquarium filled with 3 litre of water + H. verticillata 100 gr + Water hyacinth 100 gr + 20uci 14C-labeled malathion; for the second experiment (the first aquarium filled with 3 litre of water + 30 tails ofgoldfish + 20 uci 14C-labeled malathion; second aquarium filled with 3 litre of water + Water hyacinth 100 gr + 30 tailof goldfist + 20 uci 14C –labeled malathion. For the third experiment (most of contaminated fish tissue in the secondexperiment was dried at room temperature and then given to 30 mice and partly heated and then given to another 30mice. Malathion levels were then analyzed by using a liquid scintillation counter LSC-753 (Aloka. The results of alltreatments were compared using the Student t-test. It can be concluded, H. verticillata was more efficient compared tothe enceng gondok in absorbing the insecticide malathion residues in water; malathion concentration in the tissues offish fed Water hyacinth was higher than those of fish not fed Water hyacinth; contaminated fish tissue residues ofmalathion, although be heated, can not be lowered significantly, levels in the tissue.

  6. Hydrophytes lack potential to exhibit cadmium stress induced enhancement in lipid peroxidation and accumulation of proline

    Energy Technology Data Exchange (ETDEWEB)

    Dhir, Bhupinder; Sharmila, P.; Saradhi, P. Pardha

    2004-02-10

    Investigations were carried out to evaluate if hydrophytes (viz. Ceratophyllum, Wolffia, and Hydrilla) can be used as markers to assess the level of heavy metal pollution in aquatic bodies. The potential of these hydrophytes for lipid peroxidation and accumulation of proline in response to cadmium (Cd{sup 2+}) pollution was studied. Hydrophytes were raised in artificial pond water (APW) supplemented with various levels of Cd{sup 2+}. Interestingly, unlike mesophytes none of the hydrophytes showed ability to accumulate proline. Infact, in response to Cd{sup 2+} pollution hydrophytes exhibited a decline in proline levels in comparison to controls but mesophytes (viz. Brassica juncea, Vigna radiata and Triticum aestivum) showed progressive increase in the level of proline with increase in the extent of Cd{sup 2+} pollution. Mesophytes showed six to nine-fold increase in the level of proline in response to 1 mM Cd{sup 2+}. The potential of the above hydrophytes for lipid peroxidation was also low under Cd{sup 2+} stress. In contrast, as expected a significant enhancement in the lipid peroxidation was observed in all three mesophytes in response to their exposure to Cd{sup 2+}. About two-fold increase in production of malondialdehyde (a cytotoxic product of lipid peroxidation) was recorded in mesophytes exposed to 1 mM Cd{sup 2+}. However, a decline in chlorophyll (Chl a and Chl b) levels was recorded in response to Cd{sup 2+}pollution both in hydrophytes as well as mesophytes. In summary, hydrophytes neither have potential to accumulate proline nor have ability to accelerate lipid peroxidation under heavy metal stress. This suggests that the adaptive mechanism(s) existing in hydrophytes to tackle heavy metal stress is distinct from that in mesophytes.

  7. Cultivation of macroscopic marine algae and freshwater aquatic weeds. Progress report, May 1, 1978-September 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Ryther, J.H.

    1980-04-01

    Studies were continued during 1977-1978 on the growth and yields in culture of the red seaweed Gracilaria tikvahiae. Partial control of epiphytes was achieved by nutrient removal, shading, and/or biological agents. For the first time, a single clone of the alga was grown continuously throughout the year without replacement. Yields in large (2600 1) aluminum tanks averaged 21.4 g dry weight/m/sup 2/.day, equivalent to 31 tons/acre.year (15.5 ash-free dry wt tons/acre.year). Growth of gracilaria and other seaweeds in Vexar-mesh baskets in natural habitats and in the oceanic waters of a power plant cooling water intake canal were unsuccessful. Productivity of the freshwater macrophytes Lemna minor (common duckweed), Eichhornia crassipes (water hyacinth), and Hydrilla verticillata have now been measured throughout the year with mean yields of 3.7, 24.2 and 4.2 g dry weight/m/sup 2/.day (5.4, 35.3, and 6.1 dry tons/acre.year) respectively. Yields of duckweed and water hyacinths in the Harbor Branch Foundation culture units have averaged roughly three times those of the same species growing in highly-eutrophic natural environments. Chopped water hyacinths and unprocessed Gracilaria have both been successfully fermented to methane in anaerobic digesters and the liquid digester residues recycled to produce more of the same plants. A preliminary budget for recycled nitrogen has been determined for water hyacinths. Productivity of both water hyacinths and Gracilaria has been calculated from nitrate-nitrogen assimilation and good agreement with measured yields was obtained.

  8. Pollination efficiency of Apis mellifera Linnaeus, 1758 (Hymenoptera, Apidae) on the monoecious plants Jatropha mollissima (Pohl) Baill. and Jatropha mutabilis (Pohl) Baill. (Euphorbiaceae) in a semi-arid Caatinga area, northeastern Brazil.

    Science.gov (United States)

    Neves, E L; Viana, B F

    2011-02-01

    Previous studies have shown the superior competitive ability of honeybees compared with native bees in the exploitation of floral resources and nesting sites besides their low efficiency in pollinating native plant species. However, there is little evidence of the effect of this invading species on autochthonous plant populations in natural environments. Thus experiments were performed to test the pollination efficiency of honeybees in two species of Jatropha (Euphorbiaceae), J. mollissima (Pohl) Baill. and J. mutabilis (Pohl) Baill., after a single flower visitation. Samplings were carried out between March and April 2006 in a hyperxerophilous shrub-arboreal Caatinga at Estação Biológica de Canudos, Bahia (9º 56´ 34" S, 38º 59´ 17" W), the property of Fundação Biodiversitas. Apis mellifera was efficient at pollinating J. mollissima (100%) and J. mutabilis (85%). This high efficiency may be explained by 1) the simple floral characteristics of both plant species, which facilitate access to the sexual organs of the plant; and 2) the body size of A. mellifera that fits the flower's dimensions.

  9. Aquatic macrophytes in the large, sub-tropical Itaipu Reservoir, Brazil.

    Science.gov (United States)

    Mormul, Roger Paulo; Ferreira, Fernando Alves; Michelan, Thaisa Sala; Carvalho, Priscilla; Silveira, Marcio José; Thomaz, Sidinei Magela

    2010-12-01

    In the last three decades, rapid assessment surveys have become an important approach for measuring aquatic ecosystem biodiversity. These methods can be used to detect anthropogenic impacts and recognize local or global species extinctions. We present a floristic survey of the aquatic macrophytes along the Brazilian margin of the Itaipu Reservoir conducted in 2008 and compare this with a floristic survey conducted ten years earlier. We used ordination analysis to determine whether assemblage composition differed among reservoir arms. Macrophyte species were sampled in each of the 235 sampling stations using a boat, which was positioned inside three places of each macrophyte stand to record species and search for small plants. We also collected submerged plants using a rake with the boat moving at constant velocity for ten minutes. We assigned individual macrophyte species to life form and identified representative species for each life form. A total of 87 macrophyte taxa were identified. The "emergent" life forms contained the highest number of species, followed by "rooted submerged" life forms. The extensive survey of macrophytes undertaken in September 2008 recorded more species than a survey conducted between 1995 and 1998. This could be due to changes in water physico-chemistry, disturbances due to water drawdown and the long period between surveys, which may have allowed natural colonization by other species. Additionally, differences in the classification systems and taxonomic resolution used in the surveys may account for differences in the number of species recorded. Assemblage composition varied among the arms and was affected by underwater radiation (as measured using a Secchi disk) and fetch. Five non-native species were found. Two of these non-native species (Urochloa subquadripara and Hydrilla verticillata) are of special concern because they have a high frequency of occurrence and occupy large marginal areas of the reservoir. Future surveys should be

  10. Removal and tolerance of 4 submerged plants to nitrogen and phosphorus in reclaimed water%4种沉水植物对再生水中氮磷的去除速率和耐受范围

    Institute of Scientific and Technical Information of China (English)

    徐志嫱; 刘维; 苏振铎; 高杨

    2015-01-01

    [目的]研究4种沉水植物对再生水中氮、磷的去除速率和耐受范围,为以再生水作为补水的景观水体沉水植物的选择提供依据.[方法]以野外选取的伊乐藻(Elodea canadensis)、罗氏轮叶黑藻(Hydrilla verticillata)、菹草(Potamogeton crispus)和金鱼藻(Ceratophyllum demersum)4种沉水植物作为供试材料,设置含不同质量浓度TN和TP的再生水,测定有这4种沉水植物的再生水体中TN和TP质量浓度的变化,构建TN和TP质量浓度与培养时间的回归方程,并在回归方程的基础上,研究4种沉水植物对再生水中的氮、磷的去除规律.[结果]在有4种沉水植物的再生水体中,TN和TP质量浓度均随着培养时间的延长呈负指数衰减变化,沉水植物的净化能力不仅与其种类有关,而且与TN和TP初始质量浓度相关.罗氏轮叶黑藻对TN的去除能力最强,金鱼藻最低;伊乐藻对TP的去除能力最强,金鱼藻最小.菹草对氮素的耐受范围较宽,金鱼藻最窄;伊乐藻对磷素的耐受范围最宽,金鱼藻较窄.[结论]当再生水体中TN初始质量浓度为5~15 mg/L、TP初始质量浓度为0.5~1.5 mg/L时,罗氏轮叶黑藻和伊乐藻对氮磷营养盐的去除速率较高,可作为维持和改善再生水景观水体水质的先锋植物.

  11. 5种沉水植物对斜生栅藻的化感作用%Allelopathic effect of five submerged macrophytes on Senedesmus obliquus

    Institute of Scientific and Technical Information of China (English)

    闫志强; 宋本如; 刘黾; 刘燕; 吴小业; 李洁珊; 林燕珍; 冯翊果; 陈章和

    2015-01-01

    为了解不同湿地植物和不同处理方式下化感作用的差异,在实验室条件下,研究5种常见的沉水植物黑藻(Hydrilla verticillata)、伊乐藻(Elodea nuttallii)、狐尾藻(Myriophyllum spicatum)、苦草(Vallisneria natans)和皇冠草(Echinodorus amazonicus)与斜生栅藻(Scenedesmus obliquus)共培养以及用这5种植物的种植水、浸提液培养斜生栅藻时藻细胞数量及叶绿素a浓度的变化.结果显示,5种植物与斜生栅藻共培养时抑藻效果最明显(1.6×108 cellsL-1),其斜生栅藻细胞数量显著低于种植水(6.2×108 cells L-1)和浸提液组(4.5×108 cells L-1) (P< 0.05),但5种植物间的差异不显著;除黑藻外,其他4种植物的浸提液培养斜生栅藻时均表现出对斜生栅藻明显的抑制效果,斜生栅藻的相对生长率显著低于对照组和黑藻组(P<0.05);5种植物的种植水培养斜生栅藻时则表现出相对较弱的抑藻效果,且植物间差异不显著.本研究表明,沉水植物对藻类的化感作用因不同植物和不同处理而有着显著不同.

  12. Aquatic macrophytes in the large, sub-tropical Itaipu Reservoir, Brazil

    Directory of Open Access Journals (Sweden)

    Roger Paulo Mormul

    2010-12-01

    Full Text Available In the last three decades, rapid assessment surveys have become an important approach for measuring aquatic ecosystem biodiversity. These methods can be used to detect anthropogenic impacts and recognize local or global species extinctions. We present a floristic survey of the aquatic macrophytes along the Brazilian margin of the Itaipu Reservoir conducted in 2008 and compare this with a floristic survey conducted ten years earlier. We used ordination analysis to determine whether assemblage composition differed among reservoir arms. Macrophyte species were sampled in each of the 235 sampling stations using a boat, which was positioned inside three places of each macrophyte stand to record species and search for small plants. We also collected submerged plants using a rake with the boat moving at constant velocity for ten minutes. We assigned individual macrophyte species to life form and identified representative species for each life form. A total of 87 macrophyte taxa were identified. The "emergent" life forms contained the highest number of species, followed by "rooted submerged" life forms. The extensive survey of macrophytes undertaken in September 2008 recorded more species than a survey conducted between 1995 and 1998. This could be due to changes in water physico-chemistry, disturbances due to water drawdown and the long period between surveys, which may have allowed natural colonization by other species. Additionally, differences in the classification systems and taxonomic resolution used in the surveys may account for differences in the number of species recorded. Assemblage composition varied among the arms and was affected by underwater radiation (as measured using a Secchi disk and fetch. Five non-native species were found. Two of these non-native species (Urochloa subquadripara and Hydrilla verticillata are of special concern because they have a high frequency of occurrence and occupy large marginal areas of the reservoir. Future

  13. 采煤沉陷区苦草的生物学特性及其竞争机制%Biological traits and competition mechanism of Vallisneria natans in the mining subsidence area

    Institute of Scientific and Technical Information of China (English)

    张玉云; 万阳; 田焕新; 刘靓靓; 周忠泽

    2015-01-01

    采煤活动所致的动态沉陷湿地具有动态性、高潜水位和生态脆弱性等特点,探明此类人工重构湿地的水生植物群落的生物学特性及其竞争机制,有助于为采煤沉陷区湿地水生植物群落修复提供科学依据.本研究以淮南潘集区人工构建的苦草群落(Ass.Vallisneria natans)为倒,采用样方调查法,研究苦草的生物学特性及其与其他水生植物的竞争机制.结果表明,1)沉陷区苦草的生物学特性与浅水湖泊较一致.主要表现在苦草的繁殖方式、传粉方式、生活史方面,但研究区苦草以有性繁殖为主.2)沉陷区苦草能与以种子萌发形成的水烛群丛(Ass.Typha angustifolia)共生,但生物量低;在与形成两年以上的水烛群丛竞争中处于劣势,在水烛群丛盖度达到90%时苦草逐渐消失.3)沉陷区苦草在与浮叶植物莕菜群丛(Ass.Nymphoides peltatum)、苹群丛(Ass.Marsilea quadrifolia)竞争中处于弱势,其盖度、株高、生物量等指标都明显下降.4)沉陷区苦草在与沉水植物竹叶眼子菜群丛(Ass.Potamogeton malaianus)竞争中处于劣势,苦草与沉水植物黑藻群丛(Ass.Hydrilla verticillata)、狐尾藻群丛(Ass.Myrioph yllum verticillatum)、大茨藻群丛(Ass.Najas marina)、金鱼藻群丛(Ass.Ceratophyllum demersum)占据不同水层空间,种间竞争不强烈,能较好地共存.总之,苦草较之于相似生长型的植物具有较明显的竞争优势,对于具有不同生活型,尤其是挺水植物和浮叶植物,处于竞争劣势.

  14. Water quality effects of two aquatic macrophytes on eutrophic water from Lake Dianchi Caohai%两种水生植物对滇池草海富营养化水体水质的影响

    Institute of Scientific and Technical Information of China (English)

    王智; 张志勇; 张君倩; 闻学政; 王岩; 刘海琴; 严少华

    2013-01-01

    The water quality effects of two typical aquatic macrophytes, Eichhornia crassipes and Hydrilla verticillata, on the eutrophic water from Lake Dianchi Caohai were investigated by a series of microcosm experiments. The assimilation of nitrogen and phosphorus from microcosm by E. crassipes were 109% and 17% higher than that by H. verticillata, respectively. The leves of dissovle oxygen and pH in the E. crassipes treatments were significantly reduced, and electric conduction and redox potential were significantly increased comparing with the control. However, the results of H. verticillata treatments were opposive to E. crassipes treatments. During the experiment, the concentrations of total nitrogen (TN) and total phosphorus (TP) in treatments were significantly lower than that in control. With the same biomass of two aquatic plants used at the beginning of the experiment, the concentrations of TN, TP and chlorophyll-a (Chl-a) in H. verticillata treatments were significantly lower than that in E. crassipes treatments in the early stage of the experiment, but the results were reversed in the late stage of the experiment. After aquatic macrophytes harvest, concentrations of TN and TP could maintain the levels of which before harvest; Chl-a concentrations in E. crassipes treatments could also maintain the level of which before harvest, but in H. verticillata treatments, Chl-a concentrations showed a significant increase.%通过模拟实验,比较了2种典型水生植物水葫芦和轮叶黑藻对滇池草海富营养化水体水质的影响.结果表明,在实验过程中,水葫芦同化吸收的氮、磷量分别比轮叶黑藻所同化吸收的量高109%和17%.在水生植物采收前,水葫芦处理组水体DO和pH值显著性低于对照组,电导率(EC)和氧化还原电位(Eh)显著性高于对照组,与轮叶黑藻处理组结果相反.水葫芦和轮叶黑藻处理组水体TN和TP浓度均显著低于对照组;相同初始种养量的情况下,试验初

  15. 连续可调式沉水植物网床对河道水质的修复%Bioremediation of river water quality by consecutively adjustable submerged vegetation net

    Institute of Scientific and Technical Information of China (English)

    吴海龙; 霍元子; 邵留; 王阳阳; 于克锋; 何培民; 温文科

    2012-01-01

    A series of consecutively adjustable submerged vegetation nets were constructed in a polluted shallow river with a length of about 200 m and nearby the water resource protection area of Taihu Lake in East China, forming an aquatic vegetation consisted of submerged plant species Ca-bomba caroliniana, Vallisneria natans, Elodea nuttallii, Hydrilla verticillata, and Potamogeton cris-pus. The water quality indices including total nitrogen (TN), ammonium nitrogen (NH4+-N) , nitrite nitrogen (NO2--N) , nitrate nitrogen (NO3--N) , total phosphorus (TP) , and phosphate (PO43-P) were monitored, and the bioremediation effect of the vegetation nets was evaluated. After setting up the vegetation nets, the Secchi depth (SD) of the river changed from 0.5 m to 1.7-1.8 m, and the TN and TP concentrations 15 and 20 days after the nets constructed decreased by 35. 6% and 66.3% , and 29.4% and 63. 2% , respectively. After five months, the concentrations of NH4+ -N, NO2--N, NO3--N, TN, TP, and PO43-P decreased by 92. 4% , 76. 8% , 72. 7% , 73.9% , 90. 5% , and 92. 0% , respectively. This study showed that consecutively adjustable submerged vegetation net could be a potential approach for treating polluted river waters, particularly for the bioremediation of polluted small landscape shallow water bodies.%在太湖贡湖水源保护区陆域的一条长约200 m的污染河道内构建了一系列连续可调式沉水植物网床,形成了以菊花草、苦草、伊乐藻、轮叶黑藻和菹草等沉水植物构成的水生植物群落;跟踪监测了总氮(TN)、铵态氮(NH4 +-N)、亚硝态氮(NO2--N)、硝态氮(NO3--N)、总磷(TP)和磷酸盐(PO43--P)等水质指标,分析沉水植物网床引导沉水植被恢复对污染河道的水质修复效果.结果表明:沉水植被网床构建后,水体透明度显著升高,由修复前的0.5m提高到1.7 ~1.8 m;在沉水植被网床构建后的第5天和第20天,TN和TP的削减率分别为35.6%、66.3%和29.4%、63.2%;5

  16. Study on Application of Daphnia magna and Submerged Vegetation to Remediation of Landscape Water%食藻虫引导的沉水植被修复景观水体的应用研究

    Institute of Scientific and Technical Information of China (English)

    夏哲韬; 史惠祥; 李遥

    2011-01-01

    A field test of bioremediation of eutrophic water by Daphnia magna and submerged vegetation was conducted in Xixi wetland. Domesticated Daphnia magna was introduced into the water body of restoration area to ingest cyanobacteria and other phytoplanktons, and subsequently, submerged plants, such as Vallisneria, Hydrilla verticillata, Elodea canadensis and Potamogeton pectinatus were transplanted. From September 2010 to February 2011, water samples were monitored to investigate bioremediation efficiency and stability. The experiment data show that compared with the control area, Chl-a, TN, N03- -N, NH4+ -N, TP, PO43- -P and CODMn in the water body of restoration area are decreased by 45.6% , 68.8% , 97.6% , 71.5% , 65.7% , 68.5% and 67.4% respectively, DO is increased by 88.3% , and Secchi depth (SD) reaches over 2.0 m. Overall, the water quality meets the II to HI criteria specified in the national surface water quality standard. In March 2011, the inferior V water was introduced into the restoration area to test the effectiveness of the established experiment system. The results show that after one month, all the water-quality indices are significantly lower compared with the control area (P <0.01), TN, TP and CODMn are reduced by 78.2% , 50% and 43.7% , the DO is increased by 22.4% , and the SD reaches 1.5 m.%在西溪湿地进行了食藻虫引导沉水植被生态修复富营养化水体的现场试验.在修复区水体中引入经过驯化的食藻虫来滤食蓝藻等浮游藻类,然后移植苦草、轮叶黑藻、伊乐藻、龙须眼子菜等沉水植物.于2010年9月-2011年2月,对水体的水质指标进行了逐月监测,分析对西溪湿地水体的净化效果及其稳定性.结果表明:修复区水体的叶绿素a、TN、NO3- -N、NH4+ -N、TP、PO43- -P和CODMn浓度相比于对照区分别低45.6%、68.8%、97.6%、71.5%、65.7%、68.5%和67.4%,DO增加了88.3%,水体透明度达到2.0m以上,水质达到国家地

  17. Hurricane Effects on a Shallow Lake Ecosystem and Its Response to a Controlled Manipulation of Water Level

    Directory of Open Access Journals (Sweden)

    Karl E. Havens

    2001-01-01

    Full Text Available In order to reverse the damage to aquatic plant communities caused by multiple years of high water levels in Lake Okeechobee, Florida (U.S., the Governing Board of the South Florida Water Management District (SFWMD authorized a "managed recession" to substantially lower the surface elevation of the lake in spring 2000. The operation was intended to achieve lower water levels for at least 8 weeks during the summer growing season, and was predicted to result in a large-scale recovery of submerged vascular plants. We treated this operation as a whole ecosystem experiment, and assessed ecological responses using data from an existing network of water quality and submerged plant monitoring sites. As a result of large-scale discharges of water from the lake, coupled with losses to evaporation and to water supply deliveries to agriculture and other regional users, the lake surface elevation receded by approximately 1 m between April and June. Water depths in shoreline areas that historically supported submerged plant communities declined from near 1.5 m to below 0.5 m. Low water levels persisted for the entire summer. Despite shallow depths, the initial response (in June 2000 of submerged plants was very limited and water remained highly turbid (due at first to abiotic seston and later to phytoplankton blooms. Turbidity decreased in July and the biomass of plants increased. However, submerged plant biomass did not exceed levels observed during summer 1999 (when water depths were greater until August. Furthermore, a vascular plant-dominated assemblage (Vallisnera, Potamogeton, and Hydrilla that occurred in 1999 was replaced with a community of nearly 98% Chara spp. (a macro-alga in 2000. Hence, the lake’s submerged plant community appeared to revert to an earlier successional stage despite what appeared to be better conditions for growth. To explain this unexpected response, we evaluated the impacts that Hurricane Irene may have had on the lake in the

  18. 3种沉水植物对夏季高温强光照环境的生理响应%Physiological Response of Three Submerged Macrophytes to the High Temperature and Light Intensity of Summer

    Institute of Scientific and Technical Information of China (English)

    王亚林; 高园园; 于丹; 刘春花

    2015-01-01

    Invasion by exotic species has become a global problem,adversely affecting the environment,economy and even human health in the areas invaded.Elodea nuttallii and Egeria densa,belonging to Hydrocharitaceae,are two exotic submerged macrophytes species in China that display a strong invasive tendency.It has been reported that E.nuttallii and E.densa are both adapted to low temperature and light intensity.Thus,we investigated the physiological response of three Hydrocharitaceae species to the high temperature and light intensity of summer,in-cluding the two exotic species (E.nuttallii and E.densa)and one native species (Hydrilla verticillata).The stud-y was designed to explore the effects of high temperature and light intensity on the invasiveness of the two exotic macrophytes.In August 2014,all test plants were placed in the natural summer condition of high temperature and light intensity,which provided the experimental treatment.The physiological response was measured by determining photosynthetic (total chlorophyll content and the maximum quantum yield of PSII (Fv/Fm))and antioxidant (ma-londialdehyde and proline content)parameters.The physiological traits were measured on day 0,3,6,9,12,15 of the treatment.Results show that high temperature and light intensity significantly affected the physiology of all three species,especially photosynthesis.Furthermore,long term high temperature and light intensity increased the impact.From day 1 to day 3,when the temperature rose to 31℃,the total chlorophyll content of E.nuttallii and the Fv/Fm of the three macrophytes were significantly lower than their initial levels (P <0.05).From day 4 to day 6,the temperature remained at 32℃ and the total chlorophyll content and the Fv/Fm of the three macrophytes were significantly lower than their initial levels (P <0.05).Moreover,the MDA content of E.nuttallii and E.densa was significantly higher than the initial level (P <0.05).During the entire experiment,the total chlorophyll con

  19. Trade‐offs between clonal and sexual reproduction in Sagittaria latifolia (Alismataceae) scale up to affect the fitness of entire clones

    National Research Council Canada - National Science Library

    Van Drunen, Wendy E; Dorken, Marcel E

    2012-01-01

    .... • Using a common garden experiment with diclinous, clonal Sagittaria latifolia we manipulated investment in reproduction through female and male sex functions of 412 plants from monoecious and dioecious populations. • We detected a 1 : 1 trade...

  20. Aspetti di tecnica colturale in canapa da cellulosa: scelta varietale

    OpenAIRE

    Marras, Gian Franco; Spanu, Antonino; Attene, Giovanna

    1981-01-01

    During 1976 and 1977 in Oristano, Italy, has been carried out a trial concerning the yield of 5 dioecious (Superfibra, Fibranova, Eletta Campana, Carmagnola, Carmagnola selezionata) and 2 monoecious (Fibrimon 56 e Fedrina 76) cultivar of hemp. The monoecious cultivar were of French origin. The 7 cultivar yielded well with 140-160 q/ha of stalks at 15% of humidity. No difference of mean production of all cultivar has been observed between 1976 and 1977. The number of plants/m...

  1. 斧头湖水生植物多样性及群落演替研究%DIVERSITY VARIATION AND COMMUNITY SUCCESSION OF AQUATIC MACROPHYTES IN LAKE FUTOU

    Institute of Scientific and Technical Information of China (English)

    李中强; 任慧; 郝孟曦; 张萌; 徐军

    2012-01-01

    Due to extensive human activities, habitat loss and segmentation induce destruction and disappearance of aquatic plants in the shallow lakes. These activities cause secondary extinctions of aquatic animals, leading to loss of biodiversity in lakes and animal reproduction. Lake Futou, locates in southeastern Hubei Province, China, has the same functions, such as irrigation and aquaculture, as other shallow lakes in the middle and lower reaches of the Yangtze River. However, in recent 50 years, human disturbances, including reclamation, damming and over-fishing, have caused accelerated loss of diversity of aquatic plants. This worsened the ecosystem faction and seriously affected the productivity of aquatic resources and the quality of species. Thus, the aims of the this study were to understand the succession of aquatic plants in Lake Futou in recent decades and to comprehend the reasons associated with exploitation and utilization of resources in this lake. In order to investigate the aquatic plant diversity in Lake Futou, the species and community diversity were studied using field investigation in 2009, and the topology were analysed by geographical information system technique with ARC/INFO. Based on the results obtained from field investigation and previous studies, species diversity variations and succession of aquatic macrophytes community in Lake Futou from 1988 to 2009 were investigated and the reasons between the changes and some controlling factors were analyzed. The results showed that there were some variations on the number of species and dominant species of aquatic plants. Some species that were sensitive to disturbances such as Nymphaea stellata disappeared and some dominant species such as Potamogeton maackianus, Vallisneria denseserrulata and Hydrilla verticillata became sub-dominant species or accompanying species from 1988 to 2009. In addition, the introduced species such as Elodea nuttalli occurred in Lake Futou and became dominant species

  2. Burseraceae

    NARCIS (Netherlands)

    Leenhouts, P.W.; Kalkman, C.; Lam, H.J.

    1955-01-01

    Dioecious, rarely monoecious trees or shrubs. Bark of twigs with a whorl of resiniferous ducts, bordered on the outer side by a distinct, closed or more or less interrupted sinuous sclerenchymatic cylinder. Pith of the twigs, petioles and petiolules not rarely with vascular strands, those in the twi

  3. USDA 846-1 fractal melon and derived recombinant inbred lines

    Science.gov (United States)

    The Agricultural Research Service, United States Department of Agriculture announces the release of a melon (Cucumis melo L.) breeding line with highly branched, fractal-type architectural growth habit and 81 derived recombinant inbred lines (RIL). The indeterminate, monoecious USDA 846-1 produces 2...

  4. Lophopyxidaceae

    NARCIS (Netherlands)

    Sleumer, H.

    1972-01-01

    Scandent or liana-like shrubs or small trees, with interxylary bast elements, watch-spring tendrils (modified leaves or subtending leaves of inflorescences), and umbrella-like branching. Leaves spiral, simple, serrulate to crenulate, stipulate. Flowers small, regular, monoecious, in glomerules on th

  5. Dichapetalaceae

    NARCIS (Netherlands)

    Leenhouts, P.W.

    1955-01-01

    Monoecious or dioecious trees, (often scrambling) shrubs, or lianas. Twigs and bark rather tough; medullary rays in twigs many, distinct; pith rather small, usually dark-coloured and often disappearing early; wood rather hard. Stipules narrowly triangular to subulate, sometimes rather early caducous

  6. Cyperaceae—II

    NARCIS (Netherlands)

    Kern, J.H.; Nooteboom, H.P.

    1979-01-01

    Perennial herbs with tufted or creeping rhizome, monoecious, rarely dioecious. Stems arising centrally or laterally, erect or obliquely erect, mostly triquetrous or trigonous, rarely subterete, solid or sometimes hollow, often clothed at the base by persistent leaf-sheaths or their fibrous remains.

  7. Floristic composition of the southern cape forests with an annotated checklist

    CSIR Research Space (South Africa)

    Geldenhuys, CJ

    1993-02-01

    Full Text Available ). The species: family ratios of 3.1 for woody plants and 4.5 for herbaceous plants are very low when compared to other forests in Africa and to the surrounding fynbos shrublands. Bisexuality predominates all growth forms and unisexuality (dioecy and monoecy...

  8. Hybridization of the marine seaweeds, Fucus serratus and Fucus evanescens (Heterokontophyta : Phaeophyceae) in a 100-year-old zone of secondary contact

    NARCIS (Netherlands)

    Coyer, JA; Hoarau, G; Stam, WT; Olsen, JL

    2002-01-01

    Historically, the intertidal seaweeds Fucus serratus (Fs) and Fucus evanescens (Fe) were sympatric only along the western coast of Norway. In the mid-1890s, Fe (monoecious) was accidentally introduced into the Oslofjord. Putative hybridization with the endemic Fs (dioecious) was observed in Oslofjor

  9. Podocarpaceae

    NARCIS (Netherlands)

    Laubenfels, de D.J.

    1984-01-01

    Monoecious or dioecious trees and shrubs, some prostrate (and one parasitic on another member of the family, Parasitaxus, in New Caledonia). Each cotyledon, of which there are usually two but in a few cases more, a fused pair with a corresponding bifid tip. Foliage buds ranging from a loose cluster

  10. Araucariaceae

    NARCIS (Netherlands)

    Laubenfels, de D.J.

    1984-01-01

    Monoecious, medium-sized to very large trees (rarely shrubby in very exposed situations). Either four independent cotyledons or two fused pairs (which may be retained in the seed after germination). The growing point of foliage shoots quite distinct between the two genera, being just a few highly re

  11. CULTURE STUDIES ON THE LIFE-HISTORY OF CHORDARIA-LINEARIS (PHAEOPHYCEAE) FROM TIERRA-DEL-FUEGO, SOUTH-AMERICA

    NARCIS (Netherlands)

    PETERS, AF

    1992-01-01

    Studies of laboratory cultures of Chordaria linearis (Hooker et Harvey) Cotton from southernmost South America revealed that this species has an obligate sexual life history in which a macroscopic sporophyte alternates with a monoecious microscopic gametophyte. Sexual reproduction is isogamous and u

  12. Batidaceae

    NARCIS (Netherlands)

    Royen, van P.

    1955-01-01

    Dioecious or monoecious small shrubs with thick woody roots. Leaves simple, opposite, sessile, fleshy, with a distinctly saccate, colourless base. Stipules minute. Flowers unisexual, either solitary and terminal or axillary, or in small axillary spikes. ♂ Flowers subtended by bracts, enclosed in a m

  13. Fagaceae

    NARCIS (Netherlands)

    Soepadmo, E.; Steenis, van C.G.G.J.

    1972-01-01

    Monoecious trees or rarely shrubs, in Mai. evergreen, sometimes buttressed or with stilt-roots; growth mode flushwise, with perular buds. Hairs simple or stellate or fasciculate, rarely with resiniferous colleters, or scales on pits on the underside of the leaf. Leaves simple, spirally arranged, rar

  14. Ulmaceae

    NARCIS (Netherlands)

    Soepadmo, E.

    1974-01-01

    Monoecious or dioecious (?), evergreen, deciduous or semideciduous shrubs or trees, (in Mal.) unarmed and often buttressed. Growth habit (in Mal.) flush-wise, except for Trema and Parasponia. Indumentum of simple, bulbous-based unicellular hairs and/or multicellular glandular hairs. Stipules caducou

  15. Sapindaceae

    NARCIS (Netherlands)

    Stoffers, A.L.

    1984-01-01

    Monoecious or dioecious trees, shrubs or vines climbing by axillary tendrils. Leaves usually alternate, compound to decompound, often even-pinnate or rarely simple. Stipules sometimes present and then persistent or deciduous. Inflorescence consisting of terminal and/or axillary thyrses, or simple or

  16. Typhaceae

    NARCIS (Netherlands)

    Stoffers, A.L.

    1963-01-01

    Monoecious, marsh or aquatic plants, with perennial, creeping rootstocks and erect, terete stems. Leaves alternate, linear or strap-shaped, sheathing at the base, flat, slightly convex on the back. Flowers unisexual, densely crowded in simple, compact, cylindric spikes. Male inflorescence terminal a

  17. AFLP Analysis Provides Strategies for Improvement of Momordica Charantia L. (Bitter Gourd)

    Science.gov (United States)

    Monoecious bitter gourd (Momordica charantia L. var. minima and maxima Williams & Ng), a cucurbit of major economic importance, is widely cultivated in India, China, Africa, and South America. Although the morphology (i.e., growth habit and fruit shape, size, color and surface texture) of Indian bi...

  18. Baliospermum montanum (Danti): Ethnobotany, phytochemistry and pharmacology- A review

    OpenAIRE

    Mali Ravindra; Wadekar Raju

    2008-01-01

    Baliospermum montanum (Willd.) Muell-Arg (Euphorbiaceae) is a leafy monoecious undershrub distributed throughout the greater parts of India, Burma and Malaya. The various parts of the plant (leaves, roots, seeds and seed oil) are widely used by various tribal communities and forest dwellers for the treatment of variety of ailments. The roots of the plant are ascribed to possess medicinal virtues in Ayurvedic system of medicine and used in preparation of important Ayurvedic formulations. The p...

  19. On the presence of fertile gametophytes of Padina pavonica (Dictyotales, Phaeophyceae) from the Iberian coasts

    OpenAIRE

    Gómez Garreta, Amelia; Rull Lluch, Jordi; Barceló Martí, M. Carme; Ribera Siguan, M. Antonia

    2007-01-01

    The gametophytes of Padina pavonica (L.) Thivy have received little attention in literature. Both female and predominantly male monoecious gametophytes of P. pavonica are recorded for the first time in the Iberian Peninsula. A detailed description of the morphology and the disposition of oogonia and antheridia is presented. In addition, a comparison with literature data on this and other Padina species is carried out.Los gametófitos de Padina pavonica (L.) Thivy han sido escasamente reseñados...

  20. The quest for molecular regulation underlying unisexual flower development

    Directory of Open Access Journals (Sweden)

    Rómulo eSobral

    2016-02-01

    Full Text Available The understanding of the molecular mechanisms responsible for the making of a unisexual flower has been a long-standing quest in plant biology. Plants with male and female flowers can be divided mainly into two categories: dioecious and monoecious, and both sexual systems co-exist in nature in ca of 10% of the angiosperms. The establishment of male and female traits has been extensively described in a hermaphroditic flower and requires the interplay of networks, directly and indirectly related to the floral organ identity genes including hormonal regulators, transcription factors, microRNAs, and chromatin-modifying proteins. Recent transcriptomic studies have been uncovering the molecular processes underlying the establishment of unisexual flowers and there are many parallelisms between monoecious, dioecious and hermaphroditic individuals. Here, we review the paper entitled Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber published in 2014 in the Frontiers of Plant Science (volume 5 | Article 599 and discussed it in the context of recent studies with other dioecious and monoecious plants that utilized high-throughput platforms to obtain transcriptomic profiles of male and female unisexual flowers. In some unisexual flowers, the developmental programs that control organ initiation fail and male or female organs do not form, whereas in other species, organ initiation and development occur but they abort or arrest during different species-specific stages of differentiation. Therefore, a direct comparison of the pathways responsible for the establishment of unisexual flowers in different species are likely to reveal conserved modules of gene regulatory hubs involved in stamen or carpel development, as well as differences that reflect the different stages of development in which male and/or female organ arrest or loss-of-function occurs.

  1. The Quest for Molecular Regulation Underlying Unisexual Flower Development

    Science.gov (United States)

    Sobral, Rómulo; Silva, Helena G.; Morais-Cecílio, Leonor; Costa, Maria M. R.

    2016-01-01

    The understanding of the molecular mechanisms responsible for the making of a unisexual flower has been a long-standing quest in plant biology. Plants with male and female flowers can be divided mainly into two categories: dioecious and monoecious, and both sexual systems co-exist in nature in ca of 10% of the angiosperms. The establishment of male and female traits has been extensively described in a hermaphroditic flower and requires the interplay of networks, directly and indirectly related to the floral organ identity genes including hormonal regulators, transcription factors, microRNAs, and chromatin-modifying proteins. Recent transcriptomic studies have been uncovering the molecular processes underlying the establishment of unisexual flowers and there are many parallelisms between monoecious, dioecious, and hermaphroditic individuals. Here, we review the paper entitled “Comparative transcriptomic analysis of male and female flowers of monoecious Quercus suber” published in 2014 in the Frontiers of Plant Science (volume 5 |Article 599) and discussed it in the context of recent studies with other dioecious and monoecious plants that utilized high-throughput platforms to obtain transcriptomic profiles of male and female unisexual flowers. In some unisexual flowers, the developmental programs that control organ initiation fail and male or female organs do not form, whereas in other species, organ initiation and development occur but they abort or arrest during different species-specific stages of differentiation. Therefore, a direct comparison of the pathways responsible for the establishment of unisexual flowers in different species are likely to reveal conserved modules of gene regulatory hubs involved in stamen or carpel development, as well as differences that reflect the different stages of development in which male and/or female organ arrest or loss-of-function occurs. PMID:26925078

  2. A role for parasites in stabilising the fig-pollinator mutualism.

    OpenAIRE

    Dunn, Derek W.; Segar, Simon T; Jo Ridley; Ruth Chan; Crozier, Ross H.; Yu, Douglas W.; Cook, James M.

    2008-01-01

    Mutualisms are interspecific interactions in which both players benefit. Explaining their maintenance is problematic, because cheaters should outcompete cooperative conspecifics, leading to mutualism instability. Monoecious figs (Ficus) are pollinated by host-specific wasps (Agaonidae), whose larvae gall ovules in their “fruits” (syconia). Female pollinating wasps oviposit directly into Ficus ovules from inside the receptive syconium. Across Ficus species, there is a widely documented segrega...

  3. Reproductive biology of the biofuel plant Jatropha curcas in its center of origin

    OpenAIRE

    2016-01-01

    In this work, we studied the main characteristics of flowering, reproductive system and diversity of pollinators for the biofuel plant Jatropha curcas (L.) in a site of tropical southeastern Mexico, within its center of origin. The plants were monoecious with inflorescences of unisexual flowers. The male flowers produced from 3062–5016 pollen grains (266–647 per anther). The plants produced fruits with both geitonogamy and xenogamy, although insect pollination significantly increased the numb...

  4. Mapping of the Gynoecy in Bitter Gourd (Momordica charantia) Using RAD-Seq Analysis

    Science.gov (United States)

    Matsumura, Hideo; Miyagi, Norimichi; Taniai, Naoki; Fukushima, Mai; Tarora, Kazuhiko; Shudo, Ayano; Urasaki, Naoya

    2014-01-01

    Momordica charantia is a monoecious plant of the Cucurbitaceae family that has both male and female unisexual flowers. Its unique gynoecious line, OHB61-5, is essential as a maternal parent in the production of F1 cultivars. To identify the DNA markers for this gynoecy, a RAD-seq (restriction-associated DNA tag sequencing) analysis was employed to reveal genome-wide DNA polymorphisms and to genotype the F2 progeny from a cross between OHB61-5 and a monoecious line. Based on a RAD-seq analysis of F2 individuals, a linkage map was constructed using 552 co-dominant markers. In addition, after analyzing the pooled genomic DNA from monoecious or gynoecious F2 plants, several SNP loci that are genetically linked to gynoecy were identified. GTFL-1, the closest SNP locus to the putative gynoecious locus, was converted to a conventional DNA marker using invader assay technology, which is applicable to the marker-assisted selection of gynoecy in M. charantia breeding. PMID:24498029

  5. Mapping of the gynoecy in bitter gourd (Momordica charantia using RAD-seq analysis.

    Directory of Open Access Journals (Sweden)

    Hideo Matsumura

    Full Text Available Momordica charantia is a monoecious plant of the Cucurbitaceae family that has both male and female unisexual flowers. Its unique gynoecious line, OHB61-5, is essential as a maternal parent in the production of F1 cultivars. To identify the DNA markers for this gynoecy, a RAD-seq (restriction-associated DNA tag sequencing analysis was employed to reveal genome-wide DNA polymorphisms and to genotype the F2 progeny from a cross between OHB61-5 and a monoecious line. Based on a RAD-seq analysis of F2 individuals, a linkage map was constructed using 552 co-dominant markers. In addition, after analyzing the pooled genomic DNA from monoecious or gynoecious F2 plants, several SNP loci that are genetically linked to gynoecy were identified. GTFL-1, the closest SNP locus to the putative gynoecious locus, was converted to a conventional DNA marker using invader assay technology, which is applicable to the marker-assisted selection of gynoecy in M. charantia breeding.

  6. An angiosperm-wide analysis of the gynodioecy–dioecy pathway

    Science.gov (United States)

    Dufay, M.; Champelovier, P.; Käfer, J.; Henry, J. P.; Mousset, S.; Marais, G. A. B.

    2014-01-01

    Background and Aims About 6 % of an estimated total of 240 000 species of angiosperms are dioecious. The main precursors of this sexual system are thought to be monoecy and gynodioecy. A previous angiosperm-wide study revealed that many dioecious species have evolved through the monoecy pathway; some case studies and a large body of theoretical research also provide evidence in support of the gynodioecy pathway. If plants have evolved through the gynodioecy pathway, gynodioecious and dioecious species should co-occur in the same genera. However, to date, no large-scale analysis has been conducted to determine the prevalence of the gynodioecy pathway in angiosperms. In this study, this gap in knowledge was addressed by performing an angiosperm-wide survey in order to test for co-occurrence as evidence of the gynodioecy pathway. Methods Data from different sources were compiled to obtain (to our knowledge) the largest dataset on gynodioecy available, with 275 genera that include at least one gynodioecious species. This dataset was combined with a dioecy dataset from the literature, and a study was made of how often dioecious and gynodioecious species could be found in the same genera using a contingency table framework. Key Results It was found that, overall, angiosperm genera with both gynodioecious and dioecious species occur more frequently than expected, in agreement with the gynodioecy pathway. Importantly, this trend holds when studying different classes separately (or sub-classes, orders and families), suggesting that the gynodioecy pathway is not restricted to a few taxa but may instead be widespread in angiosperms. Conclusions This work complements that previously carried out on the monoecy pathway and suggests that gynodioecy is also a common pathway in angiosperms. The results also identify angiosperm families where some (or all) dioecious species may have evolved from gynodioecious precursors. These families could be the targets of future small

  7. Pollen dispersal and intensity as criteria for the minimum viable population and species reserves

    Science.gov (United States)

    McClanahan, Timothy R.

    1986-05-01

    In small populations the lack of mating individuals may cause a reduction in reproductive potential which can restrict population expansion or cause further population declines. This is especially true in outcrossing monoecious and self-incompatible dioecious plant species. Principles of pollen dispersal suggest that many small to medium size population reserves of round shape will maximize the pollen interaction within and between island reserves. Diverse and low-density ecosystems require more total area in reserves than low-diversity and high-density ecosystems.

  8. PHYSICO-CHEMICAL AND PRELIMINARY PHYTOCHEMICAL INVESTIGATION OF THUJA OCCIDENTALIS LINN. (CUPRESSACEAE DRIED LEAVES

    Directory of Open Access Journals (Sweden)

    Bhan Meenu

    2011-03-01

    Full Text Available Thuja occidentalis is a monoecious coniferous plant having a wide variety of medicinal value. It has hepatoprotective, anti-oxidant, anti-bacterial, anti-fungal, anti-cancer, anti-diabetic activity etc. In the present paper, T. occidentalis leaves has been standardized on the basis of organoleptic, physical and physico-chemical characteristics. Methanolic and hydro-alcoholic extracts have been prepared by microwave assisted extraction technique and subjected to preliminary phytochemical screening and thin layer chromatography (TLC. TLC fingerprinting profile has been obtained using different solvent systems.

  9. Cytokine Attenuation and Free Radical Scavenging Activity of a New Flavanone7,4′-Dihydroxy-3″,3″-Dimethyl -(5,6-Pyrano-2″-One)- 8- (3‴,3‴-Dimethyl Allyl)- Isolated from Mallotus philippensis: Possible Mechanism for Its Anti-Inflammatory Activity

    OpenAIRE

    Rizvi, Waseeem; Fayazuddin, Mohd; Singh, Ompal; Naeem, Syed Shariq; Moin, Shagufta; Akhtar, Kafil; Kumar, Anil

    2016-01-01

    Mallotus philippensis L.(MP) commonly known as Kamala tree in Hindi,is a small to medium-sized monoecious tree.The objective of the study was to evaluate the anti-inflammatory activity of MPand a new flavanoneisolated from it by using in vivo models of inflammation.Albino wistar rats of either sex weighing 150-200g were used. Seven groups were made (n = 6), namely normal control group (normal saline, 1 ml/kg), standard control group (acetylsalicylic acid, 100 mg/kg), methanol crude extract (3...

  10. Exact Markov chains versus diffusion theory for haploid random mating.

    Science.gov (United States)

    Tyvand, Peder A; Thorvaldsen, Steinar

    2010-05-01

    Exact discrete Markov chains are applied to the Wright-Fisher model and the Moran model of haploid random mating. Selection and mutations are neglected. At each discrete value of time t there is a given number n of diploid monoecious organisms. The evolution of the population distribution is given in diffusion variables, to compare the two models of random mating with their common diffusion limit. Only the Moran model converges uniformly to the diffusion limit near the boundary. The Wright-Fisher model allows the population size to change with the generations. Diffusion theory tends to under-predict the loss of genetic information when a population enters a bottleneck.

  11. Cytotaxonomical analysis of Momordica L. (Cucurbitaceae) species of Indian occurrence

    Indian Academy of Sciences (India)

    L. K. Bharathi; A. D. Munshi; Vinod; Shanti Chandrashekaran; T. K. Behera; A. B. Das; K. Joseph John; Vishalnath

    2011-04-01

    Somatic chromosome number and detailed karyotype analysis were carried out in six Indian Momordica species viz. M. balsamina, M. charantia, M. cochinchinensis, M. dioica, M. sahyadrica and M. cymbalaria (syn. Luffa cymbalaria; a taxon of controversial taxonomic identity). The somatic chromosome number $2n = 22$ was reconfirmed in monoecious species (M. balsamina and M. charantia). Out of four dioecious species, the chromosome number was reconfirmed in M. cochinchinensis $(2n = 28)$, M. dioica $(2n = 28)$ and M. subangulata subsp. renigera $(2n = 56)$, while in M. sahyadrica $(2n = 28)$ somatic chromosome number was reported for the first time. A new chromosome number of $2n = 18$ was reported in M. cymbalaria against its previous reports of $2n = 16$, 22. The karyotype analysis of all the species revealed significant numerical and structural variations of chromosomes. It was possible to distinguish chromosomes of M. cymbalaria from other Momordica species and also between monoecious and dioecious taxa of the genus. Morphology and crossability among the dioecious species was also studied. Evidence from morphology, crossability, pollen viability and chromosome synapsis suggests a segmental allopolyploid origin for M. subangulata subsp. renigera. The taxonomic status of the controversial taxon M. cymbalaria was also discussed using morphological, karyological and crossability data.

  12. Sex expression and floral diversity in Jatropha curcas: a population study in its center of origin

    Science.gov (United States)

    Adriano-Anaya, María de Lourdes; Pérez-Castillo, Edilma; Salvador-Figueroa, Miguel; Ruiz-González, Sonia; Vázquez-Ovando, Alfredo; Grajales-Conesa, Julieta

    2016-01-01

    Sex expression and floral morphology studies are central to understand breeding behavior and to define the productive potential of plant genotypes. In particular, the new bioenergy crop Jatropha curcas L. has been classified as a monoecious species. Nonetheless, there is no information about its reproductive diversity in the Mesoamerican region, which is considered its center of origin and diversification. Thus, we determined sex expression and floral morphology in J. curcas populations from southern Mexico and Guatemala. Our results showed that most of J. curcas specimens had typical inflorescences with separate sexes (monoecious); meanwhile, the rest were atypical (gynoecious, androecious, andromonoecious, androgynomonoecious). The most important variables to group these populations, based on a discriminant analysis, were: male flower diameter, female petal length and male nectary length. From southern Mexico “Guerrero” was the most diverse population, and “Centro” had the highest variability among the populations from Chiapas. A cluster analysis showed that the accessions from southern Mexico were grouped without showing any correlation with the geographical origin, while those accessions with atypical sexuality were grouped together. To answer the question of how informative are floral morphological traits compared to molecular markers, we perform a Mantel correlation test between the distance matrix generated in this study and the genetic distance matrix (AFLP) previously reported for the same accessions. We found significant correlation between data at the level of accessions. Our results contribute to design genetic improvement programs by using sexually and morphologically contrasting plants from the center of origin. PMID:27257548

  13. Cucumber SUPERMAN has conserved function in stamen and fruit development and a distinct role in floral patterning.

    Directory of Open Access Journals (Sweden)

    Jianyu Zhao

    Full Text Available The Arabidopsis SUPERMAN (SUP gene encodes a C2H2 type zinc finger protein that is required for maintaining the boundaries between stamens and carpels, and for regulating development of ovule outer integument. Orthologs of SUP have been characterized in bisexual flowers as well as dioecious species, but it remains elusive in monoecious plants with unisexual flowers on the same individual. Here we isolate the SUP ortholog in Cucumis sativus L (CsSUP, a monoecious vegetable. CsSUP is predominantly expressed in female specific organs: the female flower buds and ovules. Ectopic expression of CsSUP in Arabidopsis can partially complement the fruit development in sup-5 mutant, and its over-expression in wide-type leads to reduced silique length, suppressed stamen development and distorted petal patterning. Our data suggest that CsSUP plays conserved as well as distinct roles during flower and fruit development, and it may function in the boundaries and ovules to balance petal patterning, stamen and ovule development in Arabidopsis.

  14. Cucumber SUPERMAN has conserved function in stamen and fruit development and a distinct role in floral patterning.

    Science.gov (United States)

    Zhao, Jianyu; Liu, Meiling; Jiang, Li; Ding, Lian; Yan, Shuang Shuang; Zhang, Juan; Dong, Zhaobin; Ren, Huazhong; Zhang, Xiaolan

    2014-01-01

    The Arabidopsis SUPERMAN (SUP) gene encodes a C2H2 type zinc finger protein that is required for maintaining the boundaries between stamens and carpels, and for regulating development of ovule outer integument. Orthologs of SUP have been characterized in bisexual flowers as well as dioecious species, but it remains elusive in monoecious plants with unisexual flowers on the same individual. Here we isolate the SUP ortholog in Cucumis sativus L (CsSUP), a monoecious vegetable. CsSUP is predominantly expressed in female specific organs: the female flower buds and ovules. Ectopic expression of CsSUP in Arabidopsis can partially complement the fruit development in sup-5 mutant, and its over-expression in wide-type leads to reduced silique length, suppressed stamen development and distorted petal patterning. Our data suggest that CsSUP plays conserved as well as distinct roles during flower and fruit development, and it may function in the boundaries and ovules to balance petal patterning, stamen and ovule development in Arabidopsis.

  15. Production of male flowers does not decrease with plant size in insect-pollinated Sagittaria trifolia, contrary to predictions of size-dependent sex allocation

    Institute of Scientific and Technical Information of China (English)

    Bing HAN; Xiao-Fan WANG; Shuang-Quan HUANG

    2011-01-01

    It has been proposed that relative allocation to female function increases with plant size in animalpollinated species.Previous investigations in several monoecious Sagittaria species seem to run contrary to the prediction of size-dependent sex allocation (SDS),throwing doubt on the generalization of SDS.Plant size,phenotypic gender,and flower production were measured in experimental populations of an aquatic,insect-pollinated herb Sagittaria trifolia (Alismataceae) under highly different densities.The comparison of ramets produced clonally can reduce confounding effects from genetic and environmental factors.In the high-density population,48% of ramets were male without female flowers,but in the low-density population all ramets were monoecious.We observed allometric growth in reproductive allocation with ramet size,as evident in biomass of reproductive structures and number of flowers.However,within both populations female and male flower production were isometric with ramet size,in contrast to an allometric growth in femaleness as predicted by SDS.Phenotypic gender was not related to ramet size in either population.The results indicated that large plants may increase both female and male function even in animal-pollinated plants,pointing towards further studies to test the hypothesis of size-dependent sex allocation using different allocation currencies.

  16. Cytotaxonomical analysis of Momordica L. (Cucurbitaceae) species of Indian occurrence.

    Science.gov (United States)

    Bharathi, L K; Munshi, A D; Vinod; Chandrashekaran, Shanti; Behera, T K; Das, A B; John, K Joseph; Vishalnath

    2011-04-01

    Somatic chromosome number and detailed karyotype analysis were carried out in six Indian Momordica species viz. M. balsamina, M. charantia, M. cochinchinensis, M. dioica, M. sahyadrica and M. cymbalaria (syn. Luffa cymbalaria; a taxon of controversial taxonomic identity). The somatic chromosome number 2n = 22 was reconfirmed in monoecious species (M. balsamina and M. charantia). Out of four dioecious species, the chromosome number was reconfirmed in M. cochinchinensis (2n = 28), M. dioica (2n = 28) and M. subangulata subsp. renigera (2n = 56), while in M. sahyadrica (2n = 28) somatic chromosome number was reported for the first time. A new chromosome number of 2n = 18 was reported in M. cymbalaria against its previous reports of 2n = 16, 22. The karyotype analysis of all the species revealed significant numerical and structural variations of chromosomes. It was possible to distinguish chromosomes of M. cymbalaria from other Momordica species and also between monoecious and dioecious taxa of the genus. Morphology and crossability among the dioecious species was also studied. Evidence from morphology, crossability, pollen viability and chromosome synapsis suggests a segmental allopolyploid origin for M. subangulata subsp. renigera. The taxonomic status of the controversial taxon M. cymbalaria was also discussed using morphological, karyological and crossability data.

  17. A New Morphological Type of Volvox from Japanese Large Lakes and Recent Divergence of this Type and V. ferrisii in Two Different Freshwater Habitats

    Science.gov (United States)

    Nozaki, Hisayoshi; Ueki, Noriko; Isaka, Nanako; Saigo, Tokiko; Yamamoto, Kayoko; Matsuzaki, Ryo; Takahashi, Fumio; Wakabayashi, Ken-ichi; Kawachi, Masanobu

    2016-01-01

    Volvox sect. Volvox is characterized by having unique morphological characteristics, such as thick cytoplasmic bridges between adult somatic cells in the spheroids and spiny zygote walls. Species of this section are found from various freshwater habitats. Recently, three species of Volvox sect. Volvox originating from rice paddies and a marsh were studied taxonomically based on molecular and morphological data of cultured materials. However, taxonomic studies have not been performed on cultured materials of this section originating from large lake water bodies. We studied a new morphological type of Volvox sect. Volvox (“Volvox sp. Sagami”), using cultured materials originating from two large lakes and a pond in Japan. Volvox sp. Sagami produced monoecious sexual spheroids and may represent a new morphological species; it could be clearly distinguished from all previously described monoecious species of Volvox sect. Volvox by its small number of eggs or zygotes (5–25) in sexual spheroids, with short acute spines (up to 3 μm long) on the zygote walls and elongated anterior somatic cells in asexual spheroids. Based on sequences of internal transcribed spacer (ITS) regions of nuclear ribosomal DNA (rDNA; ITS-1, 5.8S rDNA and ITS-2) and plastid genes, however, the Volvox sp. Sagami lineage and its sister lineage (the monoecious species V. ferrisii) showed very small genetic differences, which correspond to the variation within a single biological species in other volvocalean algae. Since V. ferrisii was different from Volvox sp. Sagami, by having approximately 100–200 zygotes in the sexual spheroids and long spines (6–8.5 μm long) on the zygote walls, as well as growing in Japanese rice paddies, these two morphologically distinct lineages might have diverged rapidly in the two different freshwater habitats. In addition, the swimming velocity during phototaxis of Volvox sp. Sagami spheroids originating from large lakes was significantly higher than that of V

  18. Transcriptomic Analysis for Different Sex Types of Ricinus communis L. during Development from Apical Buds to Inflorescences by Digital Gene Expression Profiling.

    Science.gov (United States)

    Tan, Meilian; Xue, Jianfeng; Wang, Lei; Huang, Jiaxiang; Fu, Chunling; Yan, Xingchu

    2015-01-01

    The castor plant (Ricinus communis L.) is a versatile industrial oilseed crop with a diversity of sex patterns, its hybrid breeding for improving yield and high purity is still hampered by genetic instability of female and poor knowledge of sex expression mechanisms. To obtain some hints involved in sex expression and provide the basis for further insight into the molecular mechanisms of castor plant sex determination, we performed DGE analysis to investigate differences between the transcriptomes of apices and racemes derived from female (JXBM0705P) and monoecious (JXBM0705M) lines. A total of 18 DGE libraries were constructed from the apices and racemes of a wild monoecious line and its isogenic female derivative at three stages of apex development, in triplicate. Approximately 5.7 million clean tags per library were generated and mapped to the reference castor genome. Transcriptomic analysis showed that identical dynamic changes of gene expression were indicated in monoecious and female apical bud during its development from vegetation to reproduction, with more genes expressed at the raceme formation and infant raceme stages compare to the early leaf bud stage. More than 3000 of differentially expressed genes (DEGs) were detected in Ricinus apices at three developmental stages between two different sex types. A number of DEGs involved in hormone response and biosynthesis, such as auxin response and transport, transcription factors, signal transduction, histone demethylation/methylation, programmed cell death, and pollination, putatively associated with sex expression and reproduction were discovered, and the selected DEGs showed consistent expression between qRT-PCR validation and the DGE patterns. Most of those DEGs were suppressed at the early leaf stage in buds of the mutant, but then activated at the following transition stage (5-7-leaf stage) of buds in the mutant, and ultimately, the number of up-regulated DEGs was equal to that of down-regulation in the

  19. Transcriptomic analysis for different sex types of Ricinus communis L. during development from apical buds to inflorescences by digital gene expression profiling

    Directory of Open Access Journals (Sweden)

    Tan eMeilian

    2016-02-01

    Full Text Available The castor plant (Ricinus communis L. is a versatile industrial oilseed crop with a diversity of sex patterns, its hybrid breeding for improving yield and high purity is still hampered by genetic instability of female and poor knowledge of sex expression mechanisms. To obtain some hints involved in sex expression and provide the basis for further insight into the molecular mechanisms of castor plant sex determination, we performed DGE analysis to investigate differences between the transcriptomes of apices and racemes derived from female (JXBM0705P and monoecious (JXBM0705M lines. A total of 18 DGE libraries were constructed from the apices and racemes of a wild monoecious line and its isogenic female derivative at three stages of apex development, in triplicate. Approximately 5.7 million clean tags per library were generated and mapped to the reference castor genome. Transcriptomic analysis showed that identical dynamic changes of gene expression were indicated in monoecious and female apical bud during its development from vegetation to reproduction, with more genes expressed at the raceme formation and infant raceme stages compare to the early leaf bud stage. More than 3 thousands of differentially expressed genes (DEGs were detected in Ricinus apices at three developmental stages between two different sex types. A number of DEGs involved in hormone response and biosynthesis, especially auxin response and transport, transcription factors, signal transduction, histone demethylation/methylation, programmed cell death, and pollination, putatively associated with sex expression and reproduction were discovered, and the selected DEGs showed consistent expression between qRT-PCR validation and the DGE patterns. Most of those DEGs were suppressed at the early leaf stage in buds of the mutant, but then activated at the following transition stage (5-7-leaf stage of buds in the mutant, and ultimately, the number of up-regulated DEGs was equal to that

  20. 日本垂枝、叶籽、喇叭、斑叶及雌雄同株银杏资源调查%Ginkgo resources of different types in Japan

    Institute of Scientific and Technical Information of China (English)

    张毅; 刘伟; 李桂祥

    2014-01-01

    简述日本垂枝银杏、叶籽银杏、喇叭银杏(我国文献称“筒叶银杏”)、斑叶银杏及雌雄同株银杏实生大树、古树资源概况。查有可靠依据者共有117株,其中垂枝银杏14株,叶籽银杏78株(包括3株雄株),喇叭银杏19株,斑叶银杏4株,雌雄同株银杏2株。部分单株兼具垂枝、叶籽、喇叭、斑叶性状中的2个或3个性状,因此共有107株。实际上,该类资源的数量要远多于此。多数单株为各级政府指定的“天然纪念物”,其中国家级指定“天然纪念物”叶籽银杏8株,雌雄同株银杏1株。%Japanese ginkgo resources of different types, including Ginkgo biloba var. pendula Hort., Ginkgo biloba var. epiphylla Makino, Ginkgo biloba‘Tubifolia’, Ginkgo biloba var. variegata Cari., monoecious tree and ancient tree were summarized. The reliable recorded 117 trees investigated, 14 trees were weeping ginkgo, 78 trees were Ginkgo biloba var. epiphylla Makino (including 3 staminiferous plant), 19 trees were Ginkgo biloba‘Tubifolia’, 4 trees were Ginkgo biloba var. variegata Cari., 2 trees were monoecious plants. Some plants have combining 2 or 3 traits in weeping, Ginkgo biloba var. epiphylla, Ginkgo biloba‘Tubifolia’and Ginkgo biloba var. variegata, totally 107 trees. In fact, plant resources which had combining 2 or 3 traits were more than 107. Most of single plant was‘natural monument’designated by government at all levels. Eight plants of Ginkgo biloba var. epiphylla and 1 plant of monoecious plant were‘natural monument’designated by national government.

  1. Transcriptomic Analysis for Different Sex Types of Ricinus communis L. during Development from Apical Buds to Inflorescences by Digital Gene Expression Profiling

    Science.gov (United States)

    Tan, Meilian; Xue, Jianfeng; Wang, Lei; Huang, Jiaxiang; Fu, Chunling; Yan, Xingchu

    2016-01-01

    The castor plant (Ricinus communis L.) is a versatile industrial oilseed crop with a diversity of sex patterns, its hybrid breeding for improving yield and high purity is still hampered by genetic instability of female and poor knowledge of sex expression mechanisms. To obtain some hints involved in sex expression and provide the basis for further insight into the molecular mechanisms of castor plant sex determination, we performed DGE analysis to investigate differences between the transcriptomes of apices and racemes derived from female (JXBM0705P) and monoecious (JXBM0705M) lines. A total of 18 DGE libraries were constructed from the apices and racemes of a wild monoecious line and its isogenic female derivative at three stages of apex development, in triplicate. Approximately 5.7 million clean tags per library were generated and mapped to the reference castor genome. Transcriptomic analysis showed that identical dynamic changes of gene expression were indicated in monoecious and female apical bud during its development from vegetation to reproduction, with more genes expressed at the raceme formation and infant raceme stages compare to the early leaf bud stage. More than 3000 of differentially expressed genes (DEGs) were detected in Ricinus apices at three developmental stages between two different sex types. A number of DEGs involved in hormone response and biosynthesis, such as auxin response and transport, transcription factors, signal transduction, histone demethylation/methylation, programmed cell death, and pollination, putatively associated with sex expression and reproduction were discovered, and the selected DEGs showed consistent expression between qRT-PCR validation and the DGE patterns. Most of those DEGs were suppressed at the early leaf stage in buds of the mutant, but then activated at the following transition stage (5-7-leaf stage) of buds in the mutant, and ultimately, the number of up-regulated DEGs was equal to that of down-regulation in the

  2. Bioinformatic investigation of the role of ubiquitins in cucumber flower morphogenesis

    Science.gov (United States)

    Pawełkowicz, Magdalena; Osipowski, Paweł; Wojcieszek, Michał; Kowalczuk, Cezary; PlÄ der, Wojciech; Przybecki, Zbigniew

    2016-09-01

    Three cDNA clones were used to screen cucumber genome in order to find genes and proteins. Functional annotation reveals that they are correlated with ubiquitination pathways. Various bioinformatics tools were used to screen and check protein sequences features such as: the presence of specific domains, transmembrane regions, cleavage site and cellular placement. The computational analysis for promotor region shows many binding sites for transcription factors, which could regulate the expression of genes. In order to check gene expression levels in developing flower buds of monoecious (B10) and gynoecious (2gg) cucumber lines, the real - time PCR technique was applied. The expression was checked for the whole buds and only for the 3rd and 4th whorls of bud when generative organ are form which were obtained by Laser Capture Microdissection (LCM) technique.

  3. Genomics of sex determination.

    Science.gov (United States)

    Zhang, Jisen; Boualem, Adnane; Bendahmane, Abdelhafid; Ming, Ray

    2014-04-01

    Sex determination is a major switch in the evolutionary history of angiosperm, resulting 11% monoecious and dioecious species. The genomic sequences of papaya sex chromosomes unveiled the molecular basis of recombination suppression in the sex determination region, and candidate genes for sex determination. Identification and analyses of sex determination genes in cucurbits and maize demonstrated conservation of sex determination mechanism in one lineage and divergence between the two systems. Epigenetic control and hormonal influence of sex determination were elucidated in both plants and animals. Intensive investigation of potential sex determination genes in model species will improve our understanding of sex determination gene network. Such network will in turn accelerate the identification of sex determination genes in dioecious species with sex chromosomes, which are burdensome due to no recombination in sex determining regions. The sex determination genes in dioecious species are crucial for understanding the origin of dioecy and sex chromosomes, particularly in their early stage of evolution.

  4. Fruit production of Attalea colenda (Arecaceae) in coastal Ecuador - an alternative oil resource?

    Energy Technology Data Exchange (ETDEWEB)

    Feil, J.P. [Aarhus Univ., Risskov (Denmark)

    1996-07-01

    Attalea colenda is a monoecious palm found in pastures in coastal Ecuador. In dry regions, it is a valuable source of oil in self-sufficiency farming or in combination with cattle in pastures. The palm was studied over a gradient of dry to humid environments during two fruiting seasons. Palm growth, production of leaves, inflorescences, and infructescences, number of fruits per infructescence, and seed weight of five populations were evaluated. The individual of average size is 15 m tall, which corresponds to approximately 30-40 years of age. No difference in fruit production was recorded between wet and dry regions of coastal Ecuador. The average production of one hectare of pasture, with 50 palms, was 0.9 t of oil per year. One population that was part of an agroforestry system produced 50% more fruits than the average of all populations in pasture. 18 refs., 1 fig., 6 tabs.

  5. Epigenetic marks in the mature pollen of Quercus suber L. (Fagaceae).

    Science.gov (United States)

    Ribeiro, Teresa; Viegas, Wanda; Morais-Cecílio, Leonor

    2009-03-01

    We have analysed the distribution of epigenetic marks for histone modifications at lysine residues H3 and H4, and DNA methylation, in the nuclei of mature pollen cells of the Angiosperm tree Quercus suber; a monoecious wind pollinated species with a protandrous system, and a long post-pollination period. The ultrasonic treatment developed for the isolation of pollen nuclei proved to be a fast and reliable method, preventing the interference of cell wall autofluorescence in the in situ immunolabelling assays. In contrast with previous studies on herbaceous species with short progamic phases, our results are consistent with a high level of silent (5-mC and H3K9me2) epigenetic marks on chromatin of the generative nucleus, and the prevalence of active marks (H3K9me3 and H4Kac) in the vegetative nucleus. The findings are discussed in terms of the pollination/fertilization timing strategy adopted by this plant species.

  6. Reproductive biology of the biofuel plant Jatropha curcas in its center of origin.

    Science.gov (United States)

    Rincón-Rabanales, Manuel; Vargas-López, Laura I; Adriano-Anaya, Lourdes; Vázquez-Ovando, Alfredo; Salvador-Figueroa, Miguel; Ovando-Medina, Isidro

    2016-01-01

    In this work, we studied the main characteristics of flowering, reproductive system and diversity of pollinators for the biofuel plant Jatropha curcas (L.) in a site of tropical southeastern Mexico, within its center of origin. The plants were monoecious with inflorescences of unisexual flowers. The male flowers produced from 3062-5016 pollen grains (266-647 per anther). The plants produced fruits with both geitonogamy and xenogamy, although insect pollination significantly increased the number and quality of fruits. A high diversity of flower visiting insects (36 species) was found, of which nine were classified as efficient pollinators. The native stingless bees Scaptotrigona mexicana (Guérin-Meneville) and Trigona (Tetragonisca) angustula (Latreille) were the most frequent visitors and their presence coincided with the hours when the stigma was receptive. It is noteworthy that the female flowers open before the male flowers, favoring xenogamy, which may explain the high genetic variability reported in J. curcas for this region of the world.

  7. The Porphyra species of Helgoland (Bangiales, Rhodophyta)

    Science.gov (United States)

    Kornmann, P.; Sahling, P.-H.

    1991-03-01

    This revision of seven Porphyra species of Helgoland was based on a study of the structure of their fertile thalli and the behaviour of their spores. Regarding the reproductive organization the species may be arranged in two groups. P. leucosticta and P. purpureo-violacea are obligate monoecious species. Asexual thalli have never been observed in the field. The other five species are generally dioecious. Isomorphic sexual thalli and asexually propagating ones are mixed in uniform populations. Carpospores originating from sexual fusion develop into the diploid Conchocelis phase. Sporangia of asexual plants, though homologous in formation, produce spores of different kinds: aplanospores that give rise to the vegetative thallus directly (in P. umbilicalis, P. insolita n. sp. and P. ochotensis) and spores that develop into haploid Conchocelis (in P. laciniata and in P. linearis). P. laciniata — formerly considered synonymous with P. purpurea — is an independent species.

  8. Plant Sex Determination.

    Science.gov (United States)

    Pannell, John R

    2017-03-06

    Sex determination is as important for the fitness of plants as it is for animals, but its mechanisms appear to vary much more among plants than among animals, and the expression of gender in plants differs in important respects from that in most animals. In this Minireview, I provide an overview of the broad variety of ways in which plants determine sex. I suggest that several important peculiarities of plant sex determination can be understood by recognising that: plants show an alternation of generations between sporophytic and gametophytic phases (either of which may take control of sex determination); plants are modular in structure and lack a germ line (allowing for a quantitative expression of gender that is not common in animals); and separate sexes in plants have ultimately evolved from hermaphroditic ancestors. Most theorising about sex determination in plants has focused on dioecious species, but we have much to learn from monecious or hermaphroditic species, where sex is determined at the level of modules, tissues or cells. Because of the fundamental modularity of plant development and potentially important evolutionary links between monoecy and dioecy, it may be useful to relax the distinction often made between 'developmental sex determination' (which underpins the development of male versus female flowers in monoecious species) and 'genetic sex determination' (which underpins the separation of males and females in dioecious species, often mediated by a genetic polymorphism and sex chromosomes). I also argue for relaxing the distinction between sex determination involving a genetic polymorphism and that involving responses to environmental or hormonal cues, because non-genetic cues might easily be converted into genetic switches.

  9. Pollination and breeding system of the enigmatic South African parasitic plant Mystropetalon thomii (Mystropetalaceae): rodents welcome, but not needed.

    Science.gov (United States)

    Hobbhahn, N; Steenhuisen, S-L; Olsen, T; Midgley, J J; Johnson, S D

    2017-09-01

    Unrelated plants adapted to particular pollinator types tend to exhibit convergent evolution in floral traits. However, inferences about likely pollinators from 'pollination syndromes' can be problematic due to trait overlap among some syndromes and unusual floral architecture in some lineages. An example is the rare South African parasitic plant Mystropetalon thomii (Mystropetalaceae), which has highly unusual brush-like inflorescences that exhibit features of both bird and rodent pollination syndromes. We used camera traps to record flower visitors, quantified floral spectral reflectance and nectar and scent production, experimentally determined self-compatibility and breeding system, and studied pollen dispersal using fluorescent dyes. The dark-red inflorescences are usually monoecious, with female flowers maturing before male flowers, but some inflorescences are purely female (gynoecious). Inflorescences were visited intensively by several rodent species that carried large pollen loads, while visits by birds were extremely rare. Rodents prefer male- over female-phase inflorescences, likely because of the male flowers' higher nectar and scent production. The floral scent contains several compounds known to attract rodents. Despite the obvious pollen transfer by rodents, we found that flowers on both monoecious and gynoecious inflorescences readily set seed in the absence of rodents and even when all flower visitors are excluded. Our findings suggest that seed production occurs at least partially through apomixis and that M. thomii is not ecologically dependent on its rodent pollinators. Our study adds another species and family to the growing list of rodent-pollinated plants, thus contributing to our understanding of the floral traits associated with pollination by non-flying mammals. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

  10. 河北省唐县中国黄连木资源类型及其育性研究%Resource Types and Fertility of Pistacia chinensis Bunge in Tang County of Hebei Province

    Institute of Scientific and Technical Information of China (English)

    王文浩; 何皓; 白倩; 齐泮仑; 苏淑钗; 付兴国; 陈凤

    2014-01-01

    中国黄连木在绿化、用材、观赏、药用及油料供应等方面具有很重要的经济价值。为了摸清河北省唐县中国黄连木资源的分布特点,以便更好地合理开发利用中国黄连木资源,2012-2013年,在唐县通过电话、走访及实地查看等方法进行中国黄连木种质资源调查,同时对各类型植株进行育性及结果特性研究。结果表明,在唐县首次发现雌雄同株中国黄连木资源类型。特异资源的雌雄花序分布较为复杂,花序着生有3种情况:雌雄花序同株不同枝、雌雄花序同枝不同花序、雌雄花序同花序芽;全部资源花序构成有4种情况:雌花与雄花各自形成花序、雄花及雌花以小穗形式构成混合花序、一朵小花中花药与子房同时存在形成两性花、一个花序中同时存在单一性别的小花与两性花。育性及结果特性研究显示:雌雄同株种质的花粉与子房均具有育性,而且以雄株为父本,雌雄同株植株较雌株收获的果实更大。中国黄连木雄株、雌株、雌雄花序同株不同枝、雌雄花序同花序芽的配子体可育,母体对于果实各指标的影响可能较大,果实横径、纵径及单粒质量间均两两显著相关。%Pistacia chinensis Bunge plays an important role in the aspects of greening,timber, sightseeing,officinal and fuel supply.To know the distribution traits of P .chinensis Bunge in Tang county of Hebei province,explore and make good use of P .chinensis Bunge resource, resources investigation through calls,interview and field survey were done in Tang county between 2012 and 2013,and the fertility and fruit traits among different resources were also studied.The results showed that the exceptional monoecious P .chinensis Bunge trees were found for the first time in Tang county.The distribution of staminate and pistillate inflorescences was highly complex in monoecious P .chinensis Bunge trees

  11. Nutritive quality of romanian hemp varieties (Cannabis sativa L. with special focus on oil and metal contents of seeds

    Directory of Open Access Journals (Sweden)

    Mihoc Marcela

    2012-10-01

    Full Text Available Abstract Background The study aims to determine the nutritional value of hemp seed expressed by the oil content and by the concentration of metals (Ca, Mg, K, Fe, Mn, Zn and Cd, for five varieties of monoecious and dioecious hemp seeds approved in Romania, comparative with the concentration of these metals in the soil. Results The content of oil in hempseed registers a slight decrease in the production records of 2011, losses due to drought and low levels of precipitation during the growth period. The greatest loss is found in Diana monoecious variety (26.54-20.82% followed by Zenit varieties (27.37-22.97%, Armanca (29.27-25.32%, Silvana (28.89-25.04% and Denise (26.96-25.30%. Siccative hemp oil has a yellowish green color and an iodine index of 140–156 g I2/100 g oil. Hemp seed are rich in mineral based Ca (144–955 mg/100 g seed, Mg (237–694 mg/100 g seed, K (463–2821 mg/100 g seed, Fe (1133-2400 mg.kg-1, Mn (63–110 mg.kg-1 and Zn (42-94 mg.kg-1. For the soil the following macroelements concentrations were determined: Ca (2100–2520 mg.kg-1, Mg (320–376 mg.kg-1 and K (232–257 mg.kg-1. Mn (156–197 mg.kg-1 and Zn (54–67 mg.kg-1 remain within normal limits for Romania. The soils in the experience area contain large amounts of Fe (19000–20430 mg.kg-1. The presence of K in large quantities determines the accumulation of large quantities of Fe in the soil. Conclusion Hempseed belonging to the five Romanian varieties are rich source of nutrients (Ca, Mg, K and unsaturated oil easily digestible by the body, but the presence of Cd concentrations above the upper limit puts a question mark over the use of seeds in various food products. Hemp extracts easily certain metals from the soil. Significant amounts of Fe (1133–2400 mg.kg-1, Mn (63–110 mg.kg-1, Zn (42–94 mg.kg-1 and Cd (1.3-4.0 mg.kg-1 are found in hemp seeds. Hemp (Cannabis sativa L. is included among plants suitable for phytoremediation of soil contaminated with cadmium

  12. Isolation and Characterization of Cucumber ACC Oxidase Gene and Its Upstream

    Institute of Scientific and Technical Information of China (English)

    CHEN Yin-hua; OUYANG Bo; LI Han-xia; ZHANG Jun-hong; YE Zhi-biao

    2005-01-01

    Ethylene has been implicated as a sex-determining hormone in cucumber. Its exogenous application increases femaleness,and gynoecious genotypes were reported to produce more ethylene. 1-aminocyclopropane-1-carboxylate (ACC) oxidase (ACO) is the key enzyme in ethylene biosynthesis. In this study, a 1 200 base pair (bp) candidate fragment was amplified from the cucumber genome with degenerated primers derived from the ACO amino acid consensus sequence among different plant species. The coding region and its upstream (1 155 bp) were obtained by vector-mediated inverse PCR. The novel gene was analyzed by bioinformatics tools. Four exons and three introns were identified in the coding sequence.The spliced length of mRNA was 933 nucleotides (nts) and it encoded 311 amino acids. Phylogenic analysis result of the new gene (CsACO4, GenBank accession number AY450356) was in accordance with the evolution relationship of genetics among various plant species. Northern blotting showed that the gene expressed among female flowers of gynoecious and monoecious genotypes, it could not express in other organs. This implied that the gene might be correlated with the female behavior positively. Further work is on the way to demonstrate the complexity of the relationship between the endogenous ethylene and the sex determination.

  13. Atypical mitochondrial inheritance patterns in eukaryotes.

    Science.gov (United States)

    Breton, Sophie; Stewart, Donald T

    2015-10-01

    Mitochondrial DNA (mtDNA) is predominantly maternally inherited in eukaryotes. Diverse molecular mechanisms underlying the phenomenon of strict maternal inheritance (SMI) of mtDNA have been described, but the evolutionary forces responsible for its predominance in eukaryotes remain to be elucidated. Exceptions to SMI have been reported in diverse eukaryotic taxa, leading to the prediction that several distinct molecular mechanisms controlling mtDNA transmission are present among the eukaryotes. We propose that these mechanisms will be better understood by studying the deviations from the predominating pattern of SMI. This minireview summarizes studies on eukaryote species with unusual or rare mitochondrial inheritance patterns, i.e., other than the predominant SMI pattern, such as maternal inheritance of stable heteroplasmy, paternal leakage of mtDNA, biparental and strictly paternal inheritance, and doubly uniparental inheritance of mtDNA. The potential genes and mechanisms involved in controlling mitochondrial inheritance in these organisms are discussed. The linkage between mitochondrial inheritance and sex determination is also discussed, given that the atypical systems of mtDNA inheritance examined in this minireview are frequently found in organisms with uncommon sexual systems such as gynodioecy, monoecy, or andromonoecy. The potential of deviations from SMI for facilitating a better understanding of a number of fundamental questions in biology, such as the evolution of mtDNA inheritance, the coevolution of nuclear and mitochondrial genomes, and, perhaps, the role of mitochondria in sex determination, is considerable.

  14. A statistical design for testing apomictic diversification through linkage analysis.

    Science.gov (United States)

    Zeng, Yanru; Hou, Wei; Song, Shuang; Feng, Sisi; Shen, Lin; Xia, Guohua; Wu, Rongling

    2014-03-01

    The capacity of apomixis to generate maternal clones through seed reproduction has made it a useful characteristic for the fixation of heterosis in plant breeding. It has been observed that apomixis displays pronounced intra- and interspecific diversification, but the genetic mechanisms underlying this diversification remains elusive, obstructing the exploitation of this phenomenon in practical breeding programs. By capitalizing on molecular information in mapping populations, we describe and assess a statistical design that deploys linkage analysis to estimate and test the pattern and extent of apomictic differences at various levels from genotypes to species. The design is based on two reciprocal crosses between two individuals each chosen from a hermaphrodite or monoecious species. A multinomial distribution likelihood is constructed by combining marker information from two crosses. The EM algorithm is implemented to estimate the rate of apomixis and test its difference between two plant populations or species as the parents. The design is validated by computer simulation. A real data analysis of two reciprocal crosses between hickory (Carya cathayensis) and pecan (C. illinoensis) demonstrates the utilization and usefulness of the design in practice. The design provides a tool to address fundamental and applied questions related to the evolution and breeding of apomixis.

  15. How to be an ant on figs

    Science.gov (United States)

    Bain, Anthony; Harrison, Rhett D.; Schatz, Bertrand

    2014-05-01

    Mutualistic interactions are open to exploitation by one or other of the partners and a diversity of other organisms, and hence are best understood as being embedded in a complex network of biotic interactions. Figs participate in an obligate mutualism in that figs are dependent on agaonid fig wasps for pollination and the wasps are dependent on fig ovules for brood sites. Ants are common insect predators and abundant in tropical forests. Ants have been recorded on approximately 11% of fig species, including all six subgenera, and often affect the fig-fig pollinator interaction through their predation of either pollinating and parasitic wasps. On monoecious figs, ants are often associated with hemipterans, whereas in dioecious figs ants predominantly prey on fig wasps. A few fig species are true myrmecophytes, with domatia or food rewards for ants, and in at least one species this is linked to predation of parasitic fig wasps. Ants also play a role in dispersal of fig seeds and may be particularly important for hemi-epiphytic species, which require high quality establishment microsites in the canopy. The intersection between the fig-fig pollinator and ant-plant systems promises to provide fertile ground for understanding mutualistic interactions within the context of complex interaction networks.

  16. Interspecific hybridization transfers a previously unknown glyphosate resistance mechanism in Amaranthus species.

    Science.gov (United States)

    Gaines, Todd A; Ward, Sarah M; Bukun, Bekir; Preston, Christopher; Leach, Jan E; Westra, Philip

    2012-01-01

    A previously unknown glyphosate resistance mechanism, amplification of the 5-enolpyruvyl shikimate-3-phosphate synthase gene, was recently reported in Amaranthus palmeri. This evolved mechanism could introgress to other weedy Amaranthus species through interspecific hybridization, representing an avenue for acquisition of a novel adaptive trait. The objective of this study was to evaluate the potential for this glyphosate resistance trait to transfer via pollen from A. palmeri to five other weedy Amaranthus species (Amaranthus hybridus, Amaranthus powellii, Amaranthus retroflexus, Amaranthus spinosus, and Amaranthus tuberculatus). Field and greenhouse crosses were conducted using glyphosate-resistant male A. palmeri as pollen donors and the other Amaranthus species as pollen recipients. Hybridization between A. palmeri and A. spinosus occurred with frequencies in the field studies ranging from <0.01% to 0.4%, and 1.4% in greenhouse crosses. A majority of the A. spinosus × A. palmeri hybrids grown to flowering were monoecious and produced viable seed. Hybridization occurred in the field study between A. palmeri and A. tuberculatus (<0.2%), and between A. palmeri and A. hybridus (<0.01%). This is the first documentation of hybridization between A. palmeri and both A. spinosus and A. hybridus.

  17. Pollination requirements of seeded and seedless mini watermelon varieties cultivated under protected environment

    Directory of Open Access Journals (Sweden)

    Isac Gabriel Abrahão Bomfim

    2015-01-01

    Full Text Available The objective of this work was to evaluate the floral biology and pollination requirements of seeded and seedless mini watermelon varieties, and to determine the best varieties to cultivate under protected environment. Three seedless (HA-5106, HA-5158, and HA-5161 and two seeded (Minipol and Polimore genotypes were tested. Flowers were monitored from the pre-anthesis stage to senescence, and fruit quality was also evaluated. The evaluated treatments were hand-geitonogamous pollination (MG, cross-pollination with pollen from the Polimore variety (MCP, cross-pollination with pollen from the Minipol variety (MCM, and restricted pollination. All varieties had monoecious plants with diclinous flowers, and the stigmas remained receptive throughout anthesis. Fruit set rates of 84.62% (MG, 61.54% (MCP, 48% (MCM, and 0% (restricted were obtained for seeded varieties, but of 0% (MG, 76.36% (MCP, 82.69% (MCM, and 0% (restricted for seedless varieties. Fruits did not differ in quality among treatments within each genotype. Therefore, all the studied varieties require a pollination agent and diploid pollen for fruit set to occur, regardless of the donor variety; and Minipol or Polimore with HA-5106 or HA-5158 are the varieties recommended for cultivation in protected environment.

  18. Cytokine Attenuation and Free Radical Scavenging Activity of a New Flavanone7,4'-Dihydroxy-3″,3″-Dimethyl -(5,6-Pyrano-2″-One)- 8- (3‴,3‴-Dimethyl Allyl)- Isolated from Mallotus philippensis: Possible Mechanism for Its Anti-Inflammatory Activity.

    Science.gov (United States)

    Rizvi, Waseeem; Fayazuddin, Mohd; Singh, Ompal; Naeem, Syed Shariq; Moin, Shagufta; Akhtar, Kafil; Kumar, Anil

    2016-01-01

    Mallotus philippensis L.(MP) commonly known as Kamala tree in Hindi,is a small to medium-sized monoecious tree.The objective of the study was to evaluate the anti-inflammatory activity of MPand a new flavanoneisolated from it by using in vivo models of inflammation.Albino wistar rats of either sex weighing 150-200g were used. Seven groups were made (n = 6), namely normal control group (normal saline, 1 ml/kg), standard control group (acetylsalicylic acid, 100 mg/kg), methanol crude extract (300 and 500 mg/kg), ethylacetate fraction (300 and 500 mg/kg) and active compound 4 (new flavanone, 50 mg/kg). The anti-inflammatory activity was studied using carrageenan induced paw edema method and cotton pellet granuloma method. Levels of cytokines (TNF-α, IL-1and IL-6) and activity of antioxidant enzymeslike catalase and glutathione peroxidase were estimated. It was found that the methanol extract, ethylacetate fraction and Flavanonedemonstrated significant reduction in paw edema in carrageenan induced paw edema method as compared to control. They also diminished the serum TNF-α, IL-6 and IL-1 levels. Significantly attenuated the malondialdehyde levels and increased the activities of catalase and glutathione peroxidase in paw tissue. Similarly there was asignificant decrease in granuloma formation in cotton pellet induced granuloma method. In conclusion, MP extracts and the newflavanonepossess anti-inflammatory activity and this might be due to the inhibition of various cytokines and increased free radical scavenging activity.

  19. On the presence of fertile gametophytes of Padina pavonica (Dictyotales, Phaeophyceae from the Iberian coasts

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    Gómez Garreta, Amelia

    2007-06-01

    Full Text Available The gametophytes of Padina pavonica (L. Thivy have received little attention in literature. Both female and predominantly male monoecious gametophytes of P. pavonica are recorded for the first time in the Iberian Peninsula. A detailed description of the morphology and the disposition of oogonia and antheridia is presented. In addition, a comparison with literature data on this and other Padina species is carried out.Los gametófitos de Padina pavonica (L. Thivy han sido escasamente reseñados en la bibliografía. En este trabajo se señala por primera vez en las costas de la Península Ibérica la presencia de gametófitos fértiles de P. pavonica, tanto femeninos como monoicos predominantemente masculinos. Se presenta una detallada descripción de la disposición y la morfología de los oogonios y anteridios. Asimismo, se realiza una comparación con los datos bibliográficos de esta especie y con los de otras especies de Padina

  20. Evaluation of algorithms used to order markers on genetic maps.

    Science.gov (United States)

    Mollinari, M; Margarido, G R A; Vencovsky, R; Garcia, A A F

    2009-12-01

    When building genetic maps, it is necessary to choose from several marker ordering algorithms and criteria, and the choice is not always simple. In this study, we evaluate the efficiency of algorithms try (TRY), seriation (SER), rapid chain delineation (RCD), recombination counting and ordering (RECORD) and unidirectional growth (UG), as well as the criteria PARF (product of adjacent recombination fractions), SARF (sum of adjacent recombination fractions), SALOD (sum of adjacent LOD scores) and LHMC (likelihood through hidden Markov chains), used with the RIPPLE algorithm for error verification, in the construction of genetic linkage maps. A linkage map of a hypothetical diploid and monoecious plant species was simulated containing one linkage group and 21 markers with fixed distance of 3 cM between them. In all, 700 F(2) populations were randomly simulated with 100 and 400 individuals with different combinations of dominant and co-dominant markers, as well as 10 and 20% of missing data. The simulations showed that, in the presence of co-dominant markers only, any combination of algorithm and criteria may be used, even for a reduced population size. In the case of a smaller proportion of dominant markers, any of the algorithms and criteria (except SALOD) investigated may be used. In the presence of high proportions of dominant markers and smaller samples (around 100), the probability of repulsion linkage increases between them and, in this case, use of the algorithms TRY and SER associated to RIPPLE with criterion LHMC would provide better results.

  1. Identification of a locus characteristic of male individuals of buffalo grass [Buchloe dactyloides (Nutt.) Engelm.] by using an RAPD marker.

    Science.gov (United States)

    Li, Y X; Wang, X G; Yang, C H; Cong, L L; Wu, F F; Xue, J G; Han, Y H

    2013-09-27

    Buffalo grass [Buchloe dactyloides (Nutt.) Engelm.] plants can be either male, female, or hermaphrodite (monoecious). As there is no morphological difference in the early vegetative growth of these three classes of plants, it is worthwhile to use molecular biological methods to attempt to identify the sex of a plant at this early growth period. In this study, we identified 23 plants that had a stable sex for over at least 3 years. Of these, 9 were male plants, 10 were female plants, and 4 were hermaphrodites. Screening of 300 RAPD primers identified a primer, namely S211 (5'-ttccccgcga-3'), which is capable of identifying male plants. The specific fragment was cloned, sequenced, and submitted to the GenBank database (accession No. JN982469). When used to identify the sex of 188 plants during their first growing season, the S211 primer correctly identified 85.8% of all male plants. Our results showed that the S211 primer can identify the male, and in doing so, it facilitates buffalo grass breeding work.

  2. Masting promotes individual- and population-level reproduction by increasing pollination efficiency.

    Science.gov (United States)

    Moreira, Xoaquín; Abdala-Roberts, Luis; Linhart, Yan B; Mooney, Kailen A

    2014-04-01

    Masting is a reproductive strategy defined as the intermittent and synchronized production of large seed crops by a plant population. The pollination efficiency hypothesis proposes that masting increases pollination success in plants. Despite its general appeal, no previous studies have used long-term data together with population- and individual-level analyses to assess pollination efficiency between mast and non-mast events. Here we rigorously tested the pollination efficiency hypothesis in ponderosa pine (Pinus ponderosa), a long-lived monoecious, wind-pollinated species, using a data set on 217 trees monitored annually for 20 years. Relative investment in male and female function by individual trees did not vary between mast and non-mast years. At both the population and individual level, the rate of production of mature female cones relative to male strobili production was higher in mast than non-mast years, consistent with the predicted benefit of reproductive synchrony on reproductive success. In addition, at the individual level we found a higher conversion of unfertilized female conelets into mature female cones during a mast year compared to a non-mast year. Collectively, parallel results at the population and individual tree level provide robust evidence for the ecological, and potentially also evolutionary, benefits of masting through increased pollination efficiency.

  3. Transcriptome profile analysis of floral sex determination in cucumber.

    Science.gov (United States)

    Wu, Tao; Qin, Zhiwei; Zhou, Xiuyan; Feng, Zhuo; Du, Yalin

    2010-07-15

    Cucumber has been widely studied as a model for floral sex determination. In this investigation, we performed genome-wide transcriptional profiling of apical tissue of a gynoecious mutant (Csg-G) and the monoecious wild-type (Csg-M) of cucumber in an attempt to isolate genes involved in sex determination, using the Solexa technology. The profiling analysis revealed numerous changes in gene expression attributable to the mutation, which resulted in the down-regulation of 600 genes and the up-regulation of 143 genes. The Solexa data were confirmed by reverse transcription polymerase chain reaction (RT-PCR) and real-time quantitative RT-PCR (qRT-PCR). Gene ontology (GO) analysis revealed that the differentially expressed genes were mainly involved in biogenesis, transport and organization of cellular component, macromolecular and cellular biosynthesis, localization, establishment of localization, translation and other processes. Furthermore, the expression of some of these genes depended upon the tissue and the developmental stage of the flowers of gynoecious mutant. The results of this study suggest two important concepts, which govern sex determination in cucumber. First, the differential expression of genes involved in plant hormone signaling pathways, such as ACS, Asr1, CsIAA2, CS-AUX1 and TLP, indicate that phytohormones and their crosstalk might play a critical role in the sex determination. Second, the regulation of some transcription factors, including EREBP-9, may also be involved in this developmental process.

  4. 核桃雌雄异熟性研究进展%Research Advances on Dichogamy of Walnut

    Institute of Scientific and Technical Information of China (English)

    赵书岗; 王红霞; 张志华

    2011-01-01

    Walnut (Juglans regia L.) is monoecious plant. Dichogamy, affects sexual reproduction such as flowering and pollination, and ultimately influences the yield and quality of nut. The research situation of dichogamy in walnut was briefly introduced; and the manifestation of dichogamy in walnut, phenology characteristics, floral differentiation, genetic characteristics and utilization in cultivation was summarized so as to reflect the rule of dichogamy in walnut and provide guidance for walnut cultivation.%核桃(Juglans regia L.)为雌雄异花同株植物,其雌雄异熟性直接影响着开花、授粉等有性繁殖过程,从而影响核桃坚果的产量和品质.概述了国内外核桃雌雄异熟性的研究现状,对核桃雌雄异熟性在自然界中的表现、物候期特点、花芽分化进程、遗传特性和生产利用价值等进行了综述,以期反映核桃雌雄异熟性的规律及对高产栽培的指导意义.

  5. Riparian Ficus tree communities: the distribution and abundance of riparian fig trees in northern Thailand.

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    Pornwiwan Pothasin

    Full Text Available Fig trees (Ficus are often ecologically significant keystone species because they sustain populations of the many seed-dispersing animals that feed on their fruits. They are prominent components of riparian zones where they may also contribute to bank stability as well as supporting associated animals. The diversity and distributions of riparian fig trees in deciduous and evergreen forests in Chiang Mai Province, Northern Thailand were investigated in 2010-2012. To record the diversity and abundance of riparian fig trees, we (1 calculated stem density, species richness, and diversity indices in 20×50 m randomly selected quadrats along four streams and (2 measured the distances of individual trees from four streams to determine if species exhibit distinct distribution patterns within riparian zones. A total of 1169 individuals (from c. 4 ha were recorded in the quadrats, representing 33 Ficus species (13 monoecious and 20 dioecious from six sub-genera and about 70% of all the species recorded from northern Thailand. All 33 species had at least some stems in close proximity to the streams, but they varied in their typical proximity, with F. squamosa Roxb. and F. ischnopoda Miq the most strictly stream-side species. The riparian forests in Northern Thailand support a rich diversity and high density of Ficus species and our results emphasise the importance of fig tree within the broader priorities of riparian area conservation. Plans to maintain or restore properly functioning riparian forests need to take into account their significance.

  6. Riparian Ficus tree communities: the distribution and abundance of riparian fig trees in northern Thailand.

    Science.gov (United States)

    Pothasin, Pornwiwan; Compton, Stephen G; Wangpakapattanawong, Prasit

    2014-01-01

    Fig trees (Ficus) are often ecologically significant keystone species because they sustain populations of the many seed-dispersing animals that feed on their fruits. They are prominent components of riparian zones where they may also contribute to bank stability as well as supporting associated animals. The diversity and distributions of riparian fig trees in deciduous and evergreen forests in Chiang Mai Province, Northern Thailand were investigated in 2010-2012. To record the diversity and abundance of riparian fig trees, we (1) calculated stem density, species richness, and diversity indices in 20×50 m randomly selected quadrats along four streams and (2) measured the distances of individual trees from four streams to determine if species exhibit distinct distribution patterns within riparian zones. A total of 1169 individuals (from c. 4 ha) were recorded in the quadrats, representing 33 Ficus species (13 monoecious and 20 dioecious) from six sub-genera and about 70% of all the species recorded from northern Thailand. All 33 species had at least some stems in close proximity to the streams, but they varied in their typical proximity, with F. squamosa Roxb. and F. ischnopoda Miq the most strictly stream-side species. The riparian forests in Northern Thailand support a rich diversity and high density of Ficus species and our results emphasise the importance of fig tree within the broader priorities of riparian area conservation. Plans to maintain or restore properly functioning riparian forests need to take into account their significance.

  7. The consequences of dioecy for seed dispersal: modeling the seed-shadow handicap.

    Science.gov (United States)

    Heilbuth, J C; Ilves, K L; Otto, S P

    2001-05-01

    Recent evidence has suggested that clades of dioecious angiosperms have fewer extant species on average than those of cosexual (hermaphroditic and monoecious) relatives. Reasons for the decrease in speciation rates and/or increase in extinction rates are only beginning to be investigated. One possibility is that dioecious species suffer a competitive disadvantage with cosexuals because only half of the individuals in a dioecious population are seed bearing. When only females produce seed, offspring will be more spatially clumped and will experience more local resource competition than when every individual produces seed. We examine two spatially explicit models to determine the effect of a reduction in seed dispersers on the invasibility and persistence of dioecious populations. Even though dioecious females were allowed to produce twice as many seeds as cosexuals, our results show that a reduction in the number of seed dispersers causes a decrease in the ability of dioecious progeny to find uninhabited sites, thus reducing persistence times. These results suggest that the maintenance of dioecy in the presence of hermaphroditic competitors requires a substantial increase in relative fitness and/or a large dispersal advantage of dioecious seeds.

  8. Host pollination mode and mutualist pollinator presence: net effect of internally ovipositing parasite in the fig-wasp mutualism

    Science.gov (United States)

    Zhang, Fengping; Peng, Yanqiong; Compton, Stephen G.; Zhao, Yi; Yang, Darong

    2009-04-01

    The Ficus-their specific pollinating fig wasps (Chalcidoidea, Agaonidae) interaction presents a striking example of mutualism. Figs also shelter numerous non-pollinating fig wasps (NPFW) that exploit the fig-pollinator mutualism. Only a few NPFW species can enter figs to oviposit, they do not belong to the pollinating lineage Agaonidae. The internally ovipositing non-agaonid fig wasps can efficiently pollinate the Ficus species that were passively pollinated. However, there is no study to focus on the net effect of these internally ovipositing non-agaonid wasps in actively pollinated Ficus species. By collecting the data of fig wasp community and conducting controlled experiments, our results showed that internally ovipositing Diaziella bizarrea cannot effectively pollinate Ficus glaberrima, an actively pollinated monoecious fig tree. Furthermore, D. bizarrea failed to reproduce if they were introduced into figs without Eupristina sp., the regular pollinator, as all the figs aborted. Furthermore, although D. bizarrea had no effect on seed production in shared figs, it significantly reduced the number of Eupristina sp. progeny emerging from them. Thus, our experimental evidence shows that reproduction in Diaziella depends on the presence of agaonid pollinators, and whether internally ovipositing parasites can act as pollinators depends on the host fig’s pollination mode (active or passive). Overall, this study and others suggest a relatively limited mutualistic role for internally ovipositing fig wasps from non-pollinator (non-Agaonidae) lineages.

  9. Short Communication Mendelian inheritance, linkage, and genotypic disequilibrium in microsatellite loci of Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae-Caesalpinioideae).

    Science.gov (United States)

    Moraes, M A; Kubota, T Y K; Silva, E C B; Silva, A M; Cambuim, J; Moraes, M L T; Furlani Junior, E; Sebbenn, A M

    2016-07-29

    Hymenaea stigonocarpa is a deciduous and monoecious Neotropical tree species pollinated by bats. Due to overexploitation and habitat destruction, the population size has drastically diminished in nature. No previous study has investigated Mendelian inheritance, linkage, and genotypic disequilibrium in the available microsatellite markers in this species. So, our aim was to estimate these parameters using six microsatellite loci in a sample of 470 adults and 219 juveniles from two populations of H. stigonocarpa. In addition, 30 seeds per tree from 35 seed-trees were collected. Each seed was kept record of the seed-trees and fruit origin. Based on the six microsatellite loci, we found that only 10.6% of the cases showed significant deviations from Mendelian segregation and 15.3% showed linkage. We detected no evidence of genotypic disequilibrium between the loci in the adult trees or juveniles. Thus, our results suggest that these loci can be used with great accuracy in future genetic analyses of H. stigonocarpa populations.

  10. Sex choice in plants: facultative adjustment of the sex ratio in the perennial herb Begonia gracilis.

    Science.gov (United States)

    López, S; Domínguez, C A

    2003-11-01

    Sex allocation theory predicts that reproducing individuals will increase their fitness by facultatively adjusting their relative investment towards the rarer sex in response to population shifts in operational sex ratio (OSR). The evolution of facultative manipulation of sex ratio depends on the ability of the parents to track the conditions favouring skewed sex allocation and on the mechanism controlling sex allocation. In animals, which have well-developed sensorial mechanisms, facultative adjustment of sex ratios has been demonstrated on many occasions. In this paper, we show that plants have mechanisms that allow them to evaluate the population OSR. We simulated three different conditions of population OSR by manipulating the amount of pollen received by the female flowers of a monoecious herb, and examined the effect of this treatment on the allocation to male vs. female flowers. A shortage of pollen on the stigmas resulted in a more male-skewed sex allocation, whereas plants that experienced a relatively pollen rich environment tended to produce a more female-skewed sex allocation pattern. Our results for Begonia gracilis demonstrate that the individuals of this species are able to respond to the levels of pollination intensity experienced by their female flowers and adjust their patterns of sex allocation in accordance to the expectations of sex allocation theory.

  11. How to cheat when you cannot lie? Deceit pollination in Begonia gracilis.

    Science.gov (United States)

    Castillo, Reyna A; Caballero, Helga; Boege, Karina; Fornoni, Juan; Domínguez, César A

    2012-07-01

    Mimicry between rewarding and non-rewarding flowers within individuals has been accepted as a strategy favored by selection to deceive pollinators. It has been proposed that this mechanism relies on the exploitation of pollinator's sensory biases, but field evidence is still scarce. In this study, we describe the mechanism of deceit pollination in the monoecious herb Begonia gracilis, a species with exposed rewarding structures (pollen) and intersexual mimicry. Specifically, we test the role of mimicry and exploitation of sensory biases on the reproductive success of male (pollination visitation) and female flowers (probability of setting fruits). We show that pollinators' perception of the amount of reward provided by male flowers is influenced by the independent variation in the sizes of the androecium and the perianth. Large rewarding structures and small perianths were preferred by pollinators, suggesting a central role of the relative size of the rewarding structure on pollinators' foraging decisions. Hence, rewarding male flowers cheat pollinators by exploiting their sensory biases, a strategy followed by non-rewarding female flowers. We suggest that intersexual mimicry operates through the functional resemblance of male flowers' deceit strategy. Artificial manipulation of the flowers supports our findings in natural conditions. Overall, we propose that the continuous and independent variation in the size of the perianth and the reproductive organs among male and female flowers could itself be adaptive.

  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. Baliospermum montanum (Danti: Ethnobotany, phytochemistry and pharmacology- A review

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    Mali Ravindra

    2008-01-01

    Full Text Available Baliospermum montanum (Willd. Muell-Arg (Euphorbiaceae is a leafy monoecious undershrub distributed throughout the greater parts of India, Burma and Malaya. The various parts of the plant (leaves, roots, seeds and seed oil are widely used by various tribal communities and forest dwellers for the treatment of variety of ailments. The roots of the plant are ascribed to possess medicinal virtues in Ayurvedic system of medicine and used in preparation of important Ayurvedic formulations. The plant is documented to possess beneficial effects as digestive, anthelmintic, diuretic, diaphoretic, rubefacient, febrifuge and tonic. It believed to be useful in asthma, bronchitis, leprosy, jaundice, wounds, constipation, anemia, leucoderma and fever. Following various folk claims for cure of numerous diseases, efforts have been made by researchers to verify the efficacy of the plant through scientific biological screenings. A scrutiny of literature revealed some notable pharmacological activities of the plant such as anticancer, antimicrobial, free radical scavenging, immunomodulatory, hepatoprotective, and anthelmintic. The present review is an attempt to highlight the various ethnobotanical and traditional uses as well as phytochemical and pharmacological reports on B. montanum.

  14. Pollination syndromes in a Rainforest Area, Paraíba, Brazil

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    Afrânio César de Araújo

    2009-12-01

    Full Text Available This work aimed to identify the pollination syndromes of species in Mata do Buraquinho, PB, Brazil. The relationships among the floral attributes of the vegetable species and the rewards offered to the pollinators were evaluated. Within the 88 species studied, 50.2% were whitish flowers and 48.7% were conspicuous, mainly represented by trees and shrubs. The majority of the species (66% had small flowers, followed by large and medium flowers. Most of the shrubs, vines and herbs had small flowers. The collectivist pollination unit was the most representative (71.5%. The trees obtained the highest percentage among the collectivist species (30.1%. The tube was the predominant kind of flower (72.7%, followed by the disk, the flag and the inconspicuous. The majority of the flowers were actinomorphic (60.2%, while 38.6% were zigomorphic. Regarding the sexual systems, 88.6% were hermaphroditic flowers, while 8% were monoecious and only 3.4% were dioecious. The most frequent resource was nectar (64.7%, followed by pollen (14.7%, nectar/pollen (12.5% and oil (1.1%. Entomophilia was the predominant pollination syndrome, followed by melitophilia (57%, other insects (16.8% and psicophilia (14.7%. Melitophilia was the most representative among the trees. Ornithofilia represented 7% and chiropterophilia 3.4%. Neither ornithofilia nor chiropterophilia were found among the shrubs.

  15. Consecutive five-year analysis of paternal and maternal gene flow and contributions of gametic heterogeneities to overall genetic composition of dispersed seeds of Pinus densiflora (Pinaceae).

    Science.gov (United States)

    Iwaizumi, Masakazu G; Takahashi, Makoto; Isoda, Keiya; Austerlitz, Frédéric

    2013-09-01

    Genetic variability in monoecious woody plant populations results from the assemblage of individuals issued from asymmetrical male and female reproductive functions, produced during spatially and temporarily heterogeneous reproductive and dispersal events. Here we investigated the dispersal patterns and levels of genetic diversity and differentiation of both paternal and maternal gametes in a natural population of Pinus densiflora at the multiple-year scale as long as five consecutive years. • We analyzed the paternity and maternity for 1576 seeds and 454 candidate adult trees using nuclear DNA polymorphisms of diploid biparental embryos and haploid maternal megagametophytes at eight microsatellite loci. • Despite the low levels of genetic differentiation among gamete groups, a two-way AMOVA analysis showed that the parental origin (paternal vs. maternal gametes), the year of gamete production and their interaction had significant effects on the genetic composition of the seeds. While maternal gamete groups showed a significant FST value across the 5 years, this was not true for their paternal counterparts. Within the population, we found that the relative reproductive contributions of the paternal vs. the maternal parent differed among adult trees, the maternal contributions showing a larger year-to-year fluctuation. • The overall genetic variability of dispersed seeds appeared to result from two sources of heterogeneity: the difference between paternal and maternal patterns of reproduction and gamete dispersal and year-to-year heterogeneity of reproduction of adult trees, especially in their maternal reproduction.

  16. A role for parasites in stabilising the fig-pollinator mutualism.

    Science.gov (United States)

    Dunn, Derek W; Segar, Simon T; Ridley, Jo; Chan, Ruth; Crozier, Ross H; Yu, Douglas W; Cook, James M

    2008-03-11

    Mutualisms are interspecific interactions in which both players benefit. Explaining their maintenance is problematic, because cheaters should outcompete cooperative conspecifics, leading to mutualism instability. Monoecious figs (Ficus) are pollinated by host-specific wasps (Agaonidae), whose larvae gall ovules in their "fruits" (syconia). Female pollinating wasps oviposit directly into Ficus ovules from inside the receptive syconium. Across Ficus species, there is a widely documented segregation of pollinator galls in inner ovules and seeds in outer ovules. This pattern suggests that wasps avoid, or are prevented from ovipositing into, outer ovules, and this results in mutualism stability. However, the mechanisms preventing wasps from exploiting outer ovules remain unknown. We report that in Ficus rubiginosa, offspring in outer ovules are vulnerable to attack by parasitic wasps that oviposit from outside the syconium. Parasitism risk decreases towards the centre of the syconium, where inner ovules provide enemy-free space for pollinator offspring. We suggest that the resulting gradient in offspring viability is likely to contribute to selection on pollinators to avoid outer ovules, and by forcing wasps to focus on a subset of ovules, reduces their galling rates. This previously unidentified mechanism may therefore contribute to mutualism persistence independent of additional factors that invoke plant defences against pollinator oviposition, or physiological constraints on pollinators that prevent oviposition in all available ovules.

  17. A role for parasites in stabilising the fig-pollinator mutualism.

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    Derek W Dunn

    2008-03-01

    Full Text Available Mutualisms are interspecific interactions in which both players benefit. Explaining their maintenance is problematic, because cheaters should outcompete cooperative conspecifics, leading to mutualism instability. Monoecious figs (Ficus are pollinated by host-specific wasps (Agaonidae, whose larvae gall ovules in their "fruits" (syconia. Female pollinating wasps oviposit directly into Ficus ovules from inside the receptive syconium. Across Ficus species, there is a widely documented segregation of pollinator galls in inner ovules and seeds in outer ovules. This pattern suggests that wasps avoid, or are prevented from ovipositing into, outer ovules, and this results in mutualism stability. However, the mechanisms preventing wasps from exploiting outer ovules remain unknown. We report that in Ficus rubiginosa, offspring in outer ovules are vulnerable to attack by parasitic wasps that oviposit from outside the syconium. Parasitism risk decreases towards the centre of the syconium, where inner ovules provide enemy-free space for pollinator offspring. We suggest that the resulting gradient in offspring viability is likely to contribute to selection on pollinators to avoid outer ovules, and by forcing wasps to focus on a subset of ovules, reduces their galling rates. This previously unidentified mechanism may therefore contribute to mutualism persistence independent of additional factors that invoke plant defences against pollinator oviposition, or physiological constraints on pollinators that prevent oviposition in all available ovules.

  18. Reproductive biology of the biofuel plant Jatropha curcas in its center of origin

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    Manuel Rincón-Rabanales

    2016-03-01

    Full Text Available In this work, we studied the main characteristics of flowering, reproductive system and diversity of pollinators for the biofuel plant Jatropha curcas (L. in a site of tropical southeastern Mexico, within its center of origin. The plants were monoecious with inflorescences of unisexual flowers. The male flowers produced from 3062–5016 pollen grains (266–647 per anther. The plants produced fruits with both geitonogamy and xenogamy, although insect pollination significantly increased the number and quality of fruits. A high diversity of flower visiting insects (36 species was found, of which nine were classified as efficient pollinators. The native stingless bees Scaptotrigona mexicana (Guérin-Meneville and Trigona (Tetragonisca angustula (Latreille were the most frequent visitors and their presence coincided with the hours when the stigma was receptive. It is noteworthy that the female flowers open before the male flowers, favoring xenogamy, which may explain the high genetic variability reported in J. curcas for this region of the world.

  19. The Effects of Aphid Traits on Parasitoid Host Use and Specialist Advantage.

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    Vesna Gagic

    Full Text Available Specialization is a central concept in ecology and one of the fundamental properties of parasitoids. Highly specialized parasitoids tend to be more efficient in host-use compared to generalized parasitoids, presumably owing to the trade-off between host range and host-use efficiency. However, it remains unknown how parasitoid host specificity and host-use depends on host traits related to susceptibility to parasitoid attack. To address this question, we used data from a 13-year survey of interactions among 142 aphid and 75 parasitoid species in nine European countries. We found that only aphid traits related to local resource characteristics seem to influence the trade-off between host-range and efficiency: more specialized parasitoids had an apparent advantage (higher abundance on shared hosts on aphids with sparse colonies, ant-attendance and without concealment, and this was more evident when host relatedness was included in calculation of parasitoid specificity. More traits influenced average assemblage specialization, which was highest in aphids that are monophagous, monoecious, large, highly mobile (easily drop from a plant, without myrmecophily, habitat specialists, inhabit non-agricultural habitats and have sparse colonies. Differences in aphid wax production did not influence parasitoid host specificity and host-use. Our study is the first step in identifying host traits important for aphid parasitoid host specificity and host-use and improves our understanding of bottom-up effects of aphid traits on aphid-parasitoid food web structure.

  20. Draft genome sequence of bitter gourd (Momordica charantia), a vegetable and medicinal plant in tropical and subtropical regions.

    Science.gov (United States)

    Urasaki, Naoya; Takagi, Hiroki; Natsume, Satoshi; Uemura, Aiko; Taniai, Naoki; Miyagi, Norimichi; Fukushima, Mai; Suzuki, Shouta; Tarora, Kazuhiko; Tamaki, Moritoshi; Sakamoto, Moriaki; Terauchi, Ryohei; Matsumura, Hideo

    2017-02-01

    Bitter gourd (Momordica charantia) is an important vegetable and medicinal plant in tropical and subtropical regions globally. In this study, the draft genome sequence of a monoecious bitter gourd inbred line, OHB3-1, was analyzed. Through Illumina sequencing and de novo assembly, scaffolds of 285.5 Mb in length were generated, corresponding to ∼84% of the estimated genome size of bitter gourd (339 Mb). In this draft genome sequence, 45,859 protein-coding gene loci were identified, and transposable elements accounted for 15.3% of the whole genome. According to synteny mapping and phylogenetic analysis of conserved genes, bitter gourd was more related to watermelon (Citrullus lanatus) than to cucumber (Cucumis sativus) or melon (C. melo). Using RAD-seq analysis, 1507 marker loci were genotyped in an F2 progeny of two bitter gourd lines, resulting in an improved linkage map, comprising 11 linkage groups. By anchoring RAD tag markers, 255 scaffolds were assigned to the linkage map. Comparative analysis of genome sequences and predicted genes determined that putative trypsin-inhibitor and ribosome-inactivating genes were distinctive in the bitter gourd genome. These genes could characterize the bitter gourd as a medicinal plant. © The Author 2016. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  1. Identification of evolutionarily conserved Momordica charantia microRNAs using computational approach and its utility in phylogeny analysis.

    Science.gov (United States)

    Thirugnanasambantham, Krishnaraj; Saravanan, Subramanian; Karikalan, Kulandaivelu; Bharanidharan, Rajaraman; Lalitha, Perumal; Ilango, S; HairulIslam, Villianur Ibrahim

    2015-10-01

    Momordica charantia (bitter gourd, bitter melon) is a monoecious Cucurbitaceae with anti-oxidant, anti-microbial, anti-viral and anti-diabetic potential. Molecular studies on this economically valuable plant are very essential to understand its phylogeny and evolution. MicroRNAs (miRNAs) are conserved, small, non-coding RNA with ability to regulate gene expression by bind the 3' UTR region of target mRNA and are evolved at different rates in different plant species. In this study we have utilized homology based computational approach and identified 27 mature miRNAs for the first time from this bio-medically important plant. The phylogenetic tree developed from binary data derived from the data on presence/absence of the identified miRNAs were noticed to be uncertain and biased. Most of the identified miRNAs were highly conserved among the plant species and sequence based phylogeny analysis of miRNAs resolved the above difficulties in phylogeny approach using miRNA. Predicted gene targets of the identified miRNAs revealed their importance in regulation of plant developmental process. Reported miRNAs held sequence conservation in mature miRNAs and the detailed phylogeny analysis of pre-miRNA sequences revealed genus specific segregation of clusters. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Evolution of sexual systems, dispersal strategies and habitat selection in the liverwort genus Radula.

    Science.gov (United States)

    Devos, Nicolas; Renner, Matt A M; Gradstein, Robbert; Shaw, A Jonathan; Laenen, Benjamin; Vanderpoorten, Alain

    2011-10-01

    • Shifts in sexual systems are among the most common and important transitions in plants and are correlated with a suite of life-history traits. The evolution of sexual systems and their relationships to gametophyte size, sexual and asexual reproduction, and epiphytism are examined here in the liverwort genus Radula. • The sequence of trait acquisition and the phylogenetic correlations between those traits was investigated using comparative methods. • Shifts in sexual systems recurrently occurred from dioecy to monoecy within facultative epiphyte lineages. Production of specialized asexual gemmae was correlated to neither dioecy nor strict epiphytism. • The significant correlations among life-history traits related to sexual systems and habitat conditions suggest the existence of evolutionary trade-offs. Obligate epiphytes do not produce gemmae more frequently than facultative epiphytes and disperse by whole gametophyte fragments, presumably to avoid the sensitive protonemal stage in a habitat prone to rapid changes in moisture availability. As dispersal ranges correlate with diaspore size, this reinforces the notion that epiphytes experience strong dispersal limitations. Our results thus provide the evolutionary complement to metapopulation, metacommunity and experimental studies demonstrating trade-offs between dispersal distance, establishment ability, and life-history strategy, which may be central to the evolution of reproductive strategies in bryophytes.

  3. Sex determination in flowering plants.

    Science.gov (United States)

    Dellaporta, S L; Calderon-Urrea, A

    1993-10-01

    In many ways, plants offer unique systems through which to study sex determination. Because the production of unisexual flowers has evolved independently in many plant species, different and novel mechanisms may be operational. Hence, there is probably not one unifying mechanism that explains sex determination in plants. Advances in our understanding of sex determination will come from the analysis of the genetics, molecular biology, and biochemistry of genes controlling sexual determination in plants. Several excellent model systems for bisexual floral development (Arabidopsis and Antirrhinum), monoecy (maize), and dioecy (Silene, asparagus, and mercury) are available for such analyses. The important questions that remain concern the mechanism of action of sex determination genes and their interrelationship, if any, with homeotic genes that determine the sexual identity of floral organ primordia. At the physiological level, the connection between hormone signaling and sexuality is not well understood, although significant correlations have been discovered. Finally, once the genes that regulate these processes are identified, cloned, and studied, new strategies for the manipulation of sexuality in plants should be forthcoming.

  4. The proteome and phosphoproteome of maize pollen uncovers fertility candidate proteins.

    Science.gov (United States)

    Chao, Qing; Gao, Zhi-Fang; Wang, Yue-Feng; Li, Zhe; Huang, Xia-He; Wang, Ying-Chun; Mei, Ying-Chang; Zhao, Biligen-Gaowa; Li, Liang; Jiang, Yu-Bo; Wang, Bai-Chen

    2016-06-01

    Maize is unique since it is both monoecious and diclinous (separate male and female flowers on the same plant). We investigated the proteome and phosphoproteome of maize pollen containing modified proteins and here we provide a comprehensive pollen proteome and phosphoproteome which contain 100,990 peptides from 6750 proteins and 5292 phosphorylated sites corresponding to 2257 maize phosphoproteins, respectively. Interestingly, among the total 27 overrepresented phosphosite motifs we identified here, 11 were novel motifs, which suggested different modification mechanisms in plants compared to those of animals. Enrichment analysis of pollen phosphoproteins showed that pathways including DNA synthesis/chromatin structure, regulation of RNA transcription, protein modification, cell organization, signal transduction, cell cycle, vesicle transport, transport of ions and metabolisms, which were involved in pollen development, the following germination and pollen tube growth, were regulated by phosphorylation. In this study, we also found 430 kinases and 105 phosphatases in the maize pollen phosphoproteome, among which calcium dependent protein kinases (CDPKs), leucine rich repeat kinase, SNF1 related protein kinases and MAPK family proteins were heavily enriched and further analyzed. From our research, we also uncovered hundreds of male sterility-associated proteins and phosphoproteins that might influence maize productivity and serve as targets for hybrid maize seed production. At last, a putative complex signaling pathway involving CDPKs, MAPKs, ubiquitin ligases and multiple fertility proteins was constructed. Overall, our data provides new insight for further investigation of protein phosphorylation status in mature maize pollen and construction of maize male sterile mutants in the future.

  5. Estimation of genealogical coancestry in plant species using a pedigree reconstruction algorithm and application to an oil palm breeding population.

    Science.gov (United States)

    Cros, David; Sánchez, Leopoldo; Cochard, Benoit; Samper, Patrick; Denis, Marie; Bouvet, Jean-Marc; Fernández, Jesús

    2014-04-01

    Explicit pedigree reconstruction by simulated annealing gave reliable estimates of genealogical coancestry in plant species, especially when selfing rate was lower than 0.6, using a realistic number of markers. Genealogical coancestry information is crucial in plant breeding to estimate genetic parameters and breeding values. The approach of Fernández and Toro (Mol Ecol 15:1657-1667, 2006) to estimate genealogical coancestries from molecular data through pedigree reconstruction was limited to species with separate sexes. In this study it was extended to plants, allowing hermaphroditism and monoecy, with possible selfing. Moreover, some improvements were made to take previous knowledge on the population demographic history into account. The new method was validated using simulated and real datasets. Simulations showed that accuracy of estimates was high with 30 microsatellites, with the best results obtained for selfing rates below 0.6. In these conditions, the root mean square error (RMSE) between the true and estimated genealogical coancestry was small (0.9) and a low RMSE (pedigree data were scarce. The estimated genealogical coancestries were highly correlated (>0.9) with the molecular coancestries using 100 markers. Reconstructed pedigrees were used to estimate effective population sizes. In conclusion, this method gave reliable genealogical coancestry estimates. The strategy was implemented in the software MOLCOANC 3.0.

  6. Progress on sex differentiation in unisexual flower plants%单性花植物性别分化研究进展

    Institute of Scientific and Technical Information of China (English)

    高暝; 陈益存; 杨素素; 刘英冠; 朱慧萍; 汪阳东

    2015-01-01

    性别分化是生物界普遍存在的一个自然现象。单性花由于仅含一种有功能的性器官,通过对其研究有助于解释植物性别分化和性别决定调控机制。植物性别决定方式多样且复杂,既有通过性别决定基因决定性别,又有性染色体,通过阻止性别决定基因重组确保稳定的性别分离;同时表观遗传由于影响基因表达活性,对性别分化也发挥重要作用。此外,植物激素、遗传因子、表观遗传修饰等之间存在相互作用,共同决定单性花性别。本文从单性花分类、雌雄花表型性状差异、遗传基础、表观遗传修饰、激素调控等方面综述单性花性别分化和决定调控机理,并提出未来研究中将面临的挑战和应对策略,为揭示植物性别分化和决定的机理提供有效参考。%Sexual reproduction is a universal phenomenon in the world of eukaryotes,and sex differentiation and determination are major events in the evolutionary history of angiosperms.The production of unisexual flowers has evolved numerous times from hermaphroditic ancestors,resulting in dioecious (5%)and monoecious (7%) plant taxa.Through developmental process,two broad categories of unisexual flowers have been recognized;the former results from flowers that are bisexual at initiation and become unisexual by termination of the devel-opment of the androecium (or the male reproductive organs)or gynoecium (or the female reproductive organs) and the latter results from sex differentiation occurring before initiation of stamens and carpels.Attempts have been made to understand regulatory mechanisms for plant sex determination by investigating unisexual flowers. The determinants of sexual phenotype in plants are diverse and complicated,including sex-determining genes in monoecious plants,Zea mays (corn)and Cucumis sp.(cucumber and its relatives);sex chromosomes in Silene latifolia and Carica papaya ,which ensure the stable

  7. A consensus linkage map identifies genomic regions controlling fruit maturity and beta-carotene-associated flesh color in melon (Cucumis melo L.).

    Science.gov (United States)

    Cuevas, H E; Staub, J E; Simon, P W; Zalapa, J E

    2009-08-01

    The nutritional value and yield potential of US Western Shipping melon (USWS; Cucumis melo L.) could be improved through the introgression of genes for early fruit maturity (FM) and the enhancement of the quantity of beta-carotene (QbetaC) in fruit mesocarp (i.e., flesh color). Therefore, a set of 116 F(3) families derived from the monoecious, early FM Chinese line 'Q 3-2-2' (no beta-carotene, white mesocarp) and the andromonoecious, late FM USWS line 'Top Mark' (possessing beta-carotene, orange mesocarp) were examined during 2 years in Wisconsin, USA to identify quantitative trait loci (QTL) associated with FM and QbetaC. A 171-point F(2-3) based map was constructed and used for QTL analysis. Three QTL associated with QbetaC were detected, which explained a significant portion of the observed phenotypic variation (flesh color; R (2) = 4.0-50.0%). The map position of one QTL (beta-carM.E.9.1) was uniformly aligned with one carotenoid-related gene (Orange gene), suggesting its likely role in QbetaC in this melon population and putative relationship with the melon white flesh (wf) gene. Two major (FM.6.1 and FM.11.1; R (2) >or= 20%) and one minor QTL (FM.2.1; R (2) = 8%) were found to be associated with FM. This map was then merged with a previous recombinant inbred line (RIL)-based map used to identify seven QTL associated with QbetaC in melon fruit. This consensus map [300 molecular markers (187 co-dominant melon and 14 interspecific; 10 LG)] provides a framework for the further dissection and cloning of published QTL, which will consequently lead to more effective trait introgression in melon.

  8. First report of predation on floral visitors by crab spiders on Croton selowii Baill. (Euphorbiaceae Primeiro registro de predação de visitantes florais por aranhas-caranguejo em Croton selowii Baill. (Euphorbiaceae

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    Reinaldo Rodrigo Novo

    2010-06-01

    Full Text Available In the literature it has been extensively mentioned that crab spiders (Araneae: Thomisidae prey on floral visitors of several plant species. Here we present observations of Croton selowii Baill. (Euphorbiaceae, a monoecious species harboring individuals of crab spiders in an area of coastal vegetation of Pernambuco state, Brazil. The species is visited by several invertebrate orders, and some of them were preyed upon by the spiders, mainly Diptera species. The spiders rubbed the forelimbs within the flowers, which may constitute a strategy to camouflage these structures. Croton selowii seems to represent a suitable foraging site for the spiders, because it has a generalist pollination system (thus being visited by a wide range of invertebrate species and blooms in a period of low flower resource availability in the area.Na literatura tem sido amplamente registrado que aranhas Thomisidae predam visitantes florais de várias espécies de planta. Neste estudo nós apresentamos observações de Croton selowii Baill. (Euphorbiaceae, uma espécie monóica, abrigando aranhas Thomisidae em uma área de restinga de Pernambuco, Brasil. A espécie é visitada por invertebrados de várias ordens e vários deles são predados pelas aranhas, principalmente espécies de Diptera. As aranhas apresentaram um comportamento de esfregar as pernas dianteiras dentro das flores, o que pode ser interpretado como uma estratégia de camuflagem das pernas. Croton selowii parece representar um bom sítio de forrageamento para essas aranhas, pois possui um sistema de polinização generalista, sendo visitado por ampla gama de invertebrados e floresce em um período de baixa disponibilidade de flores na área.

  9. ACC synthase genes are polymorphic in watermelon (Citrullus spp.) and differentially expressed in flowers and in response to auxin and gibberellin.

    Science.gov (United States)

    Salman-Minkov, Ayelet; Levi, Amnon; Wolf, Shmuel; Trebitsh, Tova

    2008-05-01

    The flowering pattern of watermelon species (Citrullus spp.) is either monoecious or andromonoecious. Ethylene is known to play a critical role in floral sex determination of cucurbit species. In contrast to its feminizing effect in cucumber and melon, in watermelon ethylene promotes male flower development. In cucumber, the rate-limiting enzyme of ethylene biosynthesis, 1-aminocyclopropane-1-carboxylate (ACC) synthase (ACS), regulates unisexual flower development. To investigate the role of ethylene in flower development, we isolated four genomic sequences of ACS from watermelon (CitACS1-4). Both CitACS1 and CitACS3 are expressed in floral tissue. CitACS1 is also expressed in vegetative tissue and it may be involved in cell growth processes. Expression of CitACS1 is up-regulated by exogenous treatment with auxin, gibberellin or ACC, the immediate precursor of ethylene. No discernible differential floral sex-dependent expression pattern was observed for this gene. The CitACS3 gene is expressed in open flowers and in young staminate floral buds (male or hermaphrodite), but not in female flowers. CitACS3 is also up-regulated by ACC, and is likely to be involved in ethylene-regulated anther development. The expression of CitACS2 was not detected in vegetative or reproductive organs but was up-regulated by auxin. CitACS4 transcript was not detected under our experimental conditions. Restriction fragment length polymorphism (RFLP) and sequence tagged site (STS) marker analyses of the CitACS genes showed polymorphism among and within the different Citrullus groups, including watermelon cultivars, Citrullus lanatus var. lanatus, the central subspecies Citrullus lanatus var. citroides, and the desert species Citrullus colocynthis (L).

  10. Engineering melon plants with improved fruit shelf life using the TILLING approach.

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    Fatima Dahmani-Mardas

    Full Text Available BACKGROUND: Fruit ripening and softening are key traits that have an effect on food supply, fruit nutritional value and consequently, human health. Since ethylene induces ripening of climacteric fruit, it is one of the main targets to control fruit over ripening that leads to fruit softening and deterioration. The characterization of the ethylene pathway in Arabidopsis and tomato identified key genes that control fruit ripening. METHODOLOGY/PRINCIPAL FINDINGS: To engineer melon fruit with improved shelf-life, we conducted a translational research experiment. We set up a TILLING platform in a monoecious and climacteric melon line, cloned genes that control ethylene production and screened for induced mutations that lead to fruits with enhanced shelf life. Two missense mutations, L124F and G194D, of the ethylene biosynthetic enzyme, ACC oxidase 1, were identified and the mutant plants were characterized with respect to fruit maturation. The L124F mutation is a conservative mutation occurring away from the enzyme active site and thus was predicted to not affect ethylene production and thus fruit ripening. In contrast, G194D modification occurs in a highly conserved amino acid position predicted, by crystallographic analysis, to affect the enzymatic activity. Phenotypic analysis of the G194D mutant fruit showed complete delayed ripening and yellowing with improved shelf life and, as predicted, the L124F mutation did not have an effect. CONCLUSIONS/SIGNIFICANCE: We constructed a mutant collection of 4023 melon M2 families. Based on the TILLING of 11 genes, we calculated the overall mutation rate of one mutation every 573 kb and identified 8 alleles per tilled kilobase. We also identified a TILLING mutant with enhanced fruit shelf life. This work demonstrates the effectiveness of TILLING as a reverse genetics tool to improve crop species. As cucurbits are model species in different areas of plant biology, we anticipate that the developed tool will be

  11. Genetic structure of the aphid, Chaetosiphon fragaefolii, and its role as a vector of the Strawberry Yellow Edge Virus to a native strawberry, Fragaria chiloensis in Chile.

    Science.gov (United States)

    Lavandero, Blas; Rojas, Pamela; Ramirez, Claudio C; Salazar, Marcela; Caligari, Peter D S

    2012-01-01

    The monoecious anholocyclical aphid, Chaetosiphon fragaefolii (Cockerell) (Homoptera: Aphididae), was collected on a native strawberry, Fragaria chiloensis (L.) Duchesne (Rosales: Rosaceae) from different sites in Chile. The presence of this aphid was recorded during two consecutive years. F. chiloensis plants were collected from seven natural and cultivated growing areas in central and southern Chile. Aphids were genotyped by cross-species amplification of four microsatellite loci from other aphid species. In addition, the aphid borne virus Strawberry mild yellow edge virus was confirmed in F. chiloensis plants by double-antibody sandwich ELISA and RT-PCR. Genetic variability and structure of the aphid populations was assessed from the geo-referenced individuals through AMOVA and a Bayesian assignment test. The presence of C. fragaefolii, during the two-year study was detected in only four of the seven sites (Curepto, Contulmo, Chilián and Cucao). Genetic variation among these populations reached 19% of the total variance. When assigning the individuals to groups, these were separated in three genetic clusters geographically disjunct. Of the seven sampled sites, six were positive for the virus by RT-PCR, and five by double-antibody sandwich ELISA . The incidence of the virus ranged from 0-100%. Presence of the virus corresponded with the presence of the aphid in all but two sites (Chilian and Vilches). The greatest incidence of Strawberry mild yellow edge virus was related to the abundance of aphids. On the other hand, sequences of the coat protein gene of the different virus samples did not show correspondence with either the genetic groups of the aphids or the sampling sites. The genetic structure of aphids could suggest that dispersal is mainly through human activities, and the spread to natural areas has not yet occurred on a great scale.

  12. Phylogeny of the Cucurbitales based on DNA sequences of nine loci from three genomes: implications for morphological and sexual system evolution.

    Science.gov (United States)

    Zhang, Li-Bing; Simmons, Mark P; Kocyan, Alexander; Renner, Susanne S

    2006-05-01

    The Cucurbitales are a clade of rosids with a worldwide distribution and a striking heterogeneity in species diversity among its seven family members: the Anisophylleaceae (29-40 species), Begoniaceae (1400 spp.), Coriariaceae (15 spp.), Corynocarpaceae (6 spp.), Cucurbitaceae (800 spp.), Datiscaceae (2 spp.), and Tetramelaceae (2 spp.). Most Cucurbitales have unisexual flowers, and species are monoecious, dioecious, andromonoecious, or androdioecious. To resolve interfamilial relationships within the order and to polarize morphological character evolution, especially of flower sexual systems, we sequenced nine plastids (atpB, matK, ndhF, rbcL, the trnL-F region, and the rpl20-rps12 spacer), nuclear (18S and 26S rDNA), and mitochondrial (nad1 b/c intron) genes (together approximately 12,000 bp) of 26 representatives of the seven families plus eight outgroup taxa from six other orders of the Eurosids I. Cucurbitales are strongly supported as monophyletic and are closest to Fagales, albeit with moderate support; both together are sister to Rosales. The deepest split in the Cucurbitales is that between the Anisophylleaceae and the remaining families; next is a clade of Corynocarpaceae and Coriariaceae, followed by Cucurbitaceae, which are sister to a clade of Begoniaceae, Datiscaceae, and Tetramelaceae. Based on this topology, stipulate leaves, inferior ovaries, parietal placentation, and one-seeded fruits are inferred as ancestral in Cucurbitales; exstipulate leaves, superior ovaries, apical placentation, and many-seeded fruits evolved within the order. Bisexual flowers are reconstructed as ancestral, but dioecy appears to have evolved already in the common ancestor of Begoniaceae, Cucurbitaceae, Datiscaceae, and Tetramelaceae, and then to have been lost repeatedly in Begoniaceae and Cucurbitaceae. Both instances of androdioecy (Datisca glomerata and Schizopepon bryoniifolius) evolved from dioecious ancestors, corroborating recent hypotheses about androdioecy often

  13. Cytokine Attenuation and Free Radical Scavenging Activity of a New Flavanone7,4′-Dihydroxy-3″,3″-Dimethyl -(5,6-Pyrano-2″-One)- 8- (3‴,3‴-Dimethyl Allyl)- Isolated from Mallotus philippensis: Possible Mechanism for Its Anti-Inflammatory Activity

    Science.gov (United States)

    Singh, Ompal; Moin, Shagufta; Akhtar, Kafil; Kumar, Anil

    2016-01-01

    Mallotus philippensis L.(MP) commonly known as Kamala tree in Hindi,is a small to medium-sized monoecious tree.The objective of the study was to evaluate the anti-inflammatory activity of MPand a new flavanoneisolated from it by using in vivo models of inflammation.Albino wistar rats of either sex weighing 150-200g were used. Seven groups were made (n = 6), namely normal control group (normal saline, 1 ml/kg), standard control group (acetylsalicylic acid, 100 mg/kg), methanol crude extract (300 and 500 mg/kg), ethylacetate fraction (300 and 500 mg/kg) and active compound 4 (new flavanone, 50 mg/kg). The anti-inflammatory activity was studied using carrageenan induced paw edema method and cotton pellet granuloma method. Levels of cytokines (TNF-α, IL-1and IL-6) and activity of antioxidant enzymeslike catalase and glutathione peroxidase were estimated. It was found that the methanol extract, ethylacetate fraction and Flavanonedemonstrated significant reduction in paw edema in carrageenan induced paw edema method as compared to control. They also diminished the serum TNF-α, IL-6 and IL-1 levels. Significantly attenuated the malondialdehyde levels and increased the activities of catalase and glutathione peroxidase in paw tissue. Similarly there was asignificant decrease in granuloma formation in cotton pellet induced granuloma method. In conclusion, MP extracts and the newflavanonepossess anti-inflammatory activity and this might be due to the inhibition of various cytokines and increased free radical scavenging activity. PMID:27941980

  14. Delineating a New Heterothallic Species of Volvox (Volvocaceae, Chlorophyceae Using New Strains of "Volvox africanus".

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    Hisayoshi Nozaki

    Full Text Available The volvocine algae represent an excellent model lineage in which to study evolution of female and male genders based on comparative analyses of related species. Among these species, Volvox carteri has been extensively studied as a model of an oogamous and complex organism. However, it may have unique derived features that are not present in other species of Volvox. Therefore, information regarding the characteristics of sexual reproduction of other species of Volvox is also important. In 1971, Starr studied four types of sexuality in several global strains identified as Volvox africanus; however, further taxonomic studies of these strains have been lacking, and strains of three of the four sexual types are not available. Here, we studied the morphology, sexual reproduction, and taxonomy of two V. africanus-like species isolated recently from Lake Biwa, Japan. These two species were very similar to two sexual types described by Starr in 1971: one producing dioecious sexual spheroids in heterothallic strains and the other forming both male spheroids and monoecious spheroids in a single strain. The former species produced zygotes with a reticulate cell wall, whereas a smooth zygote wall was observed in the latter species as in V. africanus previously reported from various localities around the world. Our multigene phylogenetic analysis demonstrated that these are sister species to each other. However, the presence of a compensatory base change in the most conserved region of the secondary structure of nuclear ribosomal DNA internal transcribed spacer-2, hybrid inviability demonstrated by intercrossing experiments, and morphological differences in the density of abutment between the gelatinous material of adjacent cells (individual sheaths in the spheroid supported the recognition of the two species, V. africanus having a smooth zygote wall and V. reticuliferus Nozaki sp. nov. having a reticulate zygote wall.

  15. Threatened pollination systems in native flora of the Ogasawara (Bonin) Islands.

    Science.gov (United States)

    Abe, Tetsuto

    2006-08-01

    Various alien species have been introduced to the Ogasawara Islands (Japan). A survey was made investigating whether the native pollination systems fit an 'island syndrome' (biasing the flora to dioecy, with subdued, inconspicuous flowers) and whether alien species have disrupted the native pollination network. Flower visitors and floral traits were determined in the field (12 islands) and from the literature. Associations among floral traits such as sexual expression, flower colour and flower shape were tested. Among the 269 native flowering plants, 74.7 % are hermaphroditic, 13.0 % are dioecious and 7.1 % are monoecious. Classification by flower colour revealed that 36.0 % were white, 21.6 % green and 13.8 % yellow. Woody species (trees and shrubs) comprised 36.5 % of the flora and were associated with dioecy and white flowers. Solitary, endemic small bees were the dominant flower visitors and visited 66.7 % of the observed species on satellite islands where the native pollination networks are preserved. In contrast to the situation on the satellite islands, introduced honeybees were the most dominant pollinator (visiting 60.1 % of observed species) on the two main islands, Chichi-jima and Haha-jima, and had spread to satellite islands near Chichi-jima Island. The island syndrome for pollination systems in the Ogasawara Islands was evident in a high percentage of dioecious species, the subdued colour of the native flora and solitary flower visitors on satellite islands. The shape and colour adaptations of several flowers suggested native pollination niches for long-proboscis moths and carpenter bees. However, the domination and expansion of introduced honeybees have the potential for disruption of the native pollination network in the two main, and several satellite, islands of the Ogasawara Islands.

  16. Plasticity and diversity of the phenology of dioecious Ficus species in Taiwan

    Science.gov (United States)

    Bain, Anthony; Chou, Lien-Siang; Tzeng, Hsy-Yu; Ho, Yi-Chiao; Chiang, Yun-Peng; Chen, Wen-Hsuan; Chio, Yu-Ting; Li, Guan-Yi; Yang, Hui-Wen; Kjellberg, Finn; Hossaert-McKey, Martine

    2014-05-01

    While Ficus present a series of traits often associated with dioecy, the prevalence of dioecy in Ficus is atypical. In Asian floras, dioecious Ficus species generally outnumber monoecious ones. Further this is also true in relatively northerly locations for Ficus such as the island of Taiwan. Ficus are pollinated by species-specific wasps that use fig flowers as breeding sites. In dioecious fig species, pollinators develop only in the inflorescences of male fig trees. In this study, we investigated the reproductive phenology of four dioecious Ficus species with distinct ecologies in several locations in northern and southern Taiwan. The two first species (Ficus erecta and Ficus septica) were investigated in four locations. Reproductive phenology was quite different among sites, even within a single species. For example, F. erecta presented well-defined crops at the population level in its usual high-elevation habitat but continuous fig production at low elevations, especially in South Taiwan. The two other fig species (Ficus pedunculosa var. mearnsii and Ficus tinctoria subsp. swinhoei), are shrubs growing together along seashores in exposed locations on coral reef remnants. These two species presented quite different traits allowing the survival of pollinating wasp populations. Ficus pedunculosa var. mearnsii produced figs continuously so that fresh receptive figs were always available for the pollinating wasps while F. tinctoria subsp. swinhoei extended the period of receptivity of its figs, so that receptive figs that had been waiting for pollinating wasps were almost always available. In summary, dioecious figs in Taiwan showed remarkable variation in their phenology, within species among locations or among species within location. Nevertheless, despite this variation, the phenology of the trees always allowed survival of pollinating wasp populations. Dioecious figs seem to have adopted a differentiated set of strategies which result in high resilience of

  17. Seasonal phenology and species composition of the aphid fauna in a northern crop production area.

    Directory of Open Access Journals (Sweden)

    Sascha M Kirchner

    Full Text Available BACKGROUND: The species diversity of aphids and seasonal timing of their flight activity can have significant impacts on crop production, as aphid species differ in their ability to transmit plant viruses and flight timing affects virus epidemiology. The aim of the study was to characterise the species composition and phenology of aphid fauna in Finland in one of the northernmost intensive crop production areas of the world (latitude 64°. METHODOLOGY/PRINCIPAL FINDINGS: Flight activity was monitored in four growing seasons (2007-010 using yellow pan traps (YPTs placed in 4-8 seed potato fields and a Rothamsted suction trap. A total of 58,528 winged aphids were obtained, identified to 83 taxa based on morphology, and 34 species were additionally characterised by DNA barcoding. Seasonal flight activity patterns analysed based on YPT catch fell into three main phenology clusters. Monoecious taxa showed early or middle-season flight activity and belonged to species living on shrubs/trees or herbaceous plants, respectively. Heteroecious taxa occurred over the entire potato growing season (ca. 90 days. Abundance of aphids followed a clear 3-year cycle based on suction trap data covering a decade. Rhopalosiphum padi occurring at the end of the potato growing season was the most abundant species. The flight activity of Aphis fabae, the main vector of Potato virus Y in the region, and Aphis gossypii peaked in the beginning of potato growing season. CONCLUSIONS/SIGNIFICANCE: Detailed information was obtained on phenology of a large number aphid species, of which many are agriculturally important pests acting as vectors of plant viruses. Aphis gossypii is known as a pest in greenhouses, but our study shows that it occurs also in the field, even far in the north. The novel information on aphid phenology and ecology has wide implications for prospective pest management, particularly in light of climate change.

  18. Seed and Wasp Production in the Mutualism of Figs and Fig Wasps

    Institute of Scientific and Technical Information of China (English)

    Yao Jin-yan; Zhao Nan-xian; Chen Yi-zhu; Jia Xiao-cheng; Deng Yuan; Yu Hui

    2005-01-01

    Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ovaries which can either produce one seed or one wasp. From observation on Ficus virens Ait., we showed that female flowers with outer layer of ovaries (near to the wall of syconium) had no significant difference from that with inner and interval layer of ovaries (near to the syconium cavity), in which most seeds and wasps were produced. This meant that fig tree provided the same potential resource for seed and wasps production. Observation indicated that there was usually only one foundress in syconium at female flower phase and no competition pollinators. Measurement of the style length of female flowers and the ovipositor of pollinators indicated that most ovaries could be reached by pollinator's ovipositor. However, at the male flower phase, production of seeds was significantly more than that of wasps including non-pollinating wasps but there was no significant difference between seed and pollinating wasp production when without non-pollinating wasps produced. This result indicated that non-pollinating wasps competed ovaries not with seeds but with pollinating wasps for ovipositing. Bagged experiment showed that the sampling fig species was not self-sterile which was important for figs and wasps to survive bad season. Seed production in self-pollinated figs was not significantly different from total wasps including non-pollinating ones. This might be related with the weaker competition among wasps since bagged figs were not easy to reach by wasps from outside.

  19. Morphological and Molecular Characterization of Turkish Landraces of Cucumis melo L.

    Directory of Open Access Journals (Sweden)

    Mehtap YILDIZ

    2014-06-01

    Full Text Available Cucumis melo L. from Eastern and South-eastern Anatolian regions of Turkey were characterized by using 43 morphological traits and 207 markers obtained from 31 ISSR and 16 SSR primers. The genetic relatedness was studied by examining the Euclidian/UPGMA dendrogram obtained from the combined phenotypic-molecular data. In the combined morphological-molecular dendrogram, there were two main clusters. Sweet and non-sweet melon groups were separated and the flexuosus group accessions were discriminated from the sweet ones, but the momordica group accession was clustered with the sweet ones. Unclear South-eastern Anatolian accessions were sub-clustered separately among the sweet ones. Principle component analysis (PCA of morphological characters was used in detail to discriminate melon accessions. The cumulative proportion of variation reached 44% by first three PCA axes. The first component was mainly based on sex expression, ovary index, ovary shape, flesh thickness, seed cavity length, seed cavity width, soluble solids content, fruit shape, aroma, netting, and taste. The PCA plot based on all measured traits allowed distinction between flexuosus group, subsp.agrestis and reticulatus group. A high variation among groups was observed for the fruits characters. Netting, aroma and abscission of peduncle represent reticulatus group; a small fruit size, strong typical aroma and secondary colour distribution characterize dudaim group. Monoecy, very long fruit shape and mature fruit rind colour discriminate flexuous group; Ovary index, fruit size and flesh width distinguish subsp. agrestis group. These findings indicated wide range of variations for investigated characteristics in Turkish gene pool that provides a good source of diversity to use in melon improvement program for better yield and other traits of interest.

  20. Towards a TILLING platform for functional genomics in Piel de Sapo melons

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    Pujol Marta

    2011-08-01

    Full Text Available Abstract Background The availability of genetic and genomic resources for melon has increased significantly, but functional genomics resources are still limited for this crop. TILLING is a powerful reverse genetics approach that can be utilized to generate novel mutations in candidate genes. A TILLING resource is available for cantalupensis melons, but not for inodorus melons, the other main commercial group. Results A new ethyl methanesulfonate-mutagenized (EMS melon population was generated for the first time in an andromonoecious non-climacteric inodorus Piel de Sapo genetic background. Diverse mutant phenotypes in seedlings, vines and fruits were observed, some of which were of possible commercial interest. The population was first screened for mutations in three target genes involved in disease resistance and fruit quality (Cm-PDS, Cm-eIF4E and Cm-eIFI(iso4E. The same genes were also tilled in the available monoecious and climacteric cantalupensis EMS melon population. The overall mutation density in this first Piel de Sapo TILLING platform was estimated to be 1 mutation/1.5 Mb by screening four additional genes (Cm-ACO1, Cm-NOR, Cm-DET1 and Cm-DHS. Thirty-three point mutations were found for the seven gene targets, six of which were predicted to have an impact on the function of the protein. The genotype/phenotype correlation was demonstrated for a loss-of-function mutation in the Phytoene desaturase gene, which is involved in carotenoid biosynthesis. Conclusions The TILLING approach was successful at providing new mutations in the genetic background of Piel de Sapo in most of the analyzed genes, even in genes for which natural variation is extremely low. This new resource will facilitate reverse genetics studies in non-climacteric melons, contributing materially to future genomic and breeding studies.

  1. Pollination and reproductive biology of thirteen species of Begonia in the Serra do Mar State Park, São Paulo, Brazil

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    Graham Edward Wyatt

    2012-01-01

    Full Text Available The reproductive biology of 13 monoecious species of Begonia L. (Begoniaceae that occur in the Serra do Mar State Park, São Paulo, Brazil, was investigated. These species flower annually and present flowers with mostly white tepals, light and sweet odour, pollen as a reward but no nectar, numerous yellow stamens, and coiled yellow styles. Anthesis is diurnal and floral duration is long (6 - 15 days. The unusual appearance of pistillate flowers of these species supports the view that they are intersexual mimics of the staminate flowers. Despite consistently high levels of fruit-set, none of the 11 species tested proved to be apomictic. In contrast to earlier reports of self-compatibility in Begonia, self-pollinations of B. integerrima and B. itatinensis produced no fruits or seeds, and the complete absence of pollen tubes in the styles of self-pollinated flowers of B. integerrima suggests that the species is genetically self-incompatible. Flowers pollinated under natural conditions showed many pollen tubes that reached ovules, suggesting that adequate numbers of compatible pollen grains had been transported by pollinators. The principal pollinators were small bees of the Apidae and Halictidae. Ten species of bees were observed to visit eight species of Begonia, and pollen collection occurred by means of vibration, except for Trigona spinipes. Visits to rewarding staminate flowers were significantly more frequent than visits to unrewarding pistillate flowers. Duration of visits to pistillate flowers also was significantly shorter than the duration of visits to staminate flowers. We conclude that visits to pistillate flowers occur by mistake but with sufficient frequency to allow for successful reproduction in natural populations of these species.

  2. Relative investment in egg load and poison sac in fig wasps: Implications for physiological mechanisms underlying seed and wasp production in figs

    Science.gov (United States)

    Martinson, Ellen O.; Jandér, K. Charlotte; Peng, Yan-Qiong; Chen, Huan-Huan; Machado, Carlos A.; Arnold, A. Elizabeth; Herre, Edward Allen

    2014-05-01

    Fig pollinating wasps and most non-pollinator wasps apply secretions from their poison sacs into oviposited flowers that appear necessary to the formation of the galls that their developing offspring consume. Thus, both eggs and poison sac secretions appear to be essential for wasp reproduction, but the relative investment in each is unknown. We measured relative investment in poison sac and egg production in pollinating and non-pollinating wasps associated with seven species of monoecious Panamanian figs representing both active and passive pollination syndromes. We then collected similar data for four fig hosts in China, where some wasp species in the genus Eupristina have lost the ability to pollinate ("cheaters"). All wasps examined possessed large poison sacs, and we found a strong positive correlation between poison sac size and absolute egg production. In the Panamanian species, the relative poison sac to egg investment was highest in the externally ovipositing non-pollinator wasps, followed by active pollinators, then by passive pollinators. Further, pollinator wasps of fig species with demonstrated host sanctions against "cheating" wasps showed higher investment in the poison sac than wasps of species without sanctions. In the Chinese samples, relative investment in the poison sac was indistinguishable between pollinators and "cheaters" associated with the same fig species. We suggest that higher relative investment in poison sac across fig wasp species reflects higher relative difficulty in initiating formation of galls and subsequently obtaining resources from the fig. We discuss the implications for the stability of the fig-wasp mutualism, and for the ability of non-pollinators to exploit this mutualism.

  3. A comparative study on phytochemical investigation and pharmacological screening of Platycladus orientalis and Ocimum canum

    Directory of Open Access Journals (Sweden)

    Jhansee Mishra

    2016-10-01

    Full Text Available In ayurveda, plants have been used for the treatment of so many diseases. Herbal drugs are easily available and have fewer side effects. So, many people are attracted towards the herbal drugs. Platycladus orientalis is one of the useful plant in Indian & Chinese medicine. It is used in treatment of so many diseases like diuretic, anticancer, anticonvulsant, stomachic, antipyretic, analgesic and anthelmintic etc. In Zimbabwe, Mozambique and South Africa Platycladus orientalis is grown as an ornamental. The essential oils extracted from leaves, cones and wood are important in body care products used in the Western world.Platycladus orientalis (Commonly- Morpankhi, Family- Cupressaceae is an evergreen, monoecious trees or shrubs used in various forms of traditional medicines and homeopathy in various ways. In traditional practices Thuja is used for treatment of bronchial catarrh, enuresis, cystitis, psoriasis, uterine carcinomas, amenorrhea and rheumatism. Recent re-searches in different parts of the world have shown that p. orientalis and its active component thujone have the great potential against a various health problemsThe medicinal plants are widely used by the traditional medical practitioners for curing various diseases in their day to day practice. In traditional systems of medicine, different parts (leaves, stem, flower, root, seeds and even whole plant of Ocimum canum Linn (known as  kalaTulsi in Hindi, a small herb seen throughout India, have been recommended for the treatment of bronchitis, bronchial asthma, malaria, diarrhea, dysentery, skin diseases, arthritis, painful eye diseases, chronic fever, insect bite etc. The Ocimum canum L. has also been suggested to possess antifertility, anticancer, antidiabetic, antifungal, antimicrobial, hepatoprotective, cardioprotective, antiemetic, antispasmodic, analgesic,adaptogenic and diaphoretic actions.

  4. Plant sexual systems and a review of the breeding system studies in the Caatinga, a Brazilian tropical dry forest.

    Science.gov (United States)

    Machado, Isabel Cristina; Lopes, Ariadna Valentina; Sazima, Marlies

    2006-02-01

    The reproductive biology of a community can provide answers to questions related to the maintenance of the intraspecific pollen flow and reproductive success of populations, sharing and competition for pollinators and also questions on conservation of natural habitats affected by fragmentation processes. This work presents, for the first time, data on the occurrence and frequency of plant sexual systems for Caatinga communities, and a review of the breeding system studies of Caatinga species. The sexual systems of 147 species from 34 families and 91 genera occurring in three Caatinga areas in north-eastern Brazil were analysed and compared with worldwide studies focusing on reproductive biology of different tropical communities. The frequency of hermaphrodite species was 83.0 % (122 species), seven of these (or 4.8 % of the total) being heterostylous. Monoecy occurred in 9.5 % (14) of the species, and andromonoecy in 4.8 % (seven). Only 2.7 % (four) of the species were dioecious. A high percentage of hermaphrodite species was expected and has been reported for other tropical ecosystems. With respect to the breeding system studies with species of the Caatinga, the authors' data for 21 species and an additional 18 species studied by others (n = 39) revealed a high percentage (61.5 %) of obligatory self-incompatibility. Agamospermy was not recorded among the Caatinga studied species. The plant sexual systems in the Caatinga, despite the semi-arid climate, are similar to other tropical dry and wet forest communities, including those with high rainfall levels, except for the much lower percentage of dioecious species. The high frequency of self-incompatible species is similar to that reported for Savanna areas in Brazil, and also for dry (deciduous and semideciduous) and humid tropical forest communities.

  5. The quest for epigenetic regulation underlying unisexual flower development in Cucumis melo

    KAUST Repository

    Latrasse, David

    2017-05-08

    BackgroundMelon (Cucumis melo) is an important vegetable crop from the Cucurbitaceae family and a reference model specie for sex determination, fruit ripening and vascular fluxes studies. Nevertheless, the nature and role of its epigenome in gene expression regulation and more specifically in sex determination remains largely unknown.ResultsWe have investigated genome wide H3K27me3 and H3K9ac histone modifications and gene expression dynamics, in five melon organs. H3K9ac and H3K27me3 were mainly distributed along gene-rich regions and constrained to gene bodies. H3K9ac was preferentially located at the TSS, whereas H3K27me3 distributed uniformly from TSS to TES. As observed in other species, H3K9ac and H3K27me3 correlated with high and low gene expression levels, respectively. Comparative analyses of unisexual flowers pointed out sex-specific epigenetic states of TFs involved in ethylene response and flower development. Chip-qPCR analysis of laser dissected carpel and stamina primordia, revealed sex-specific histone modification of MADS-box genes. Using sex transition mutants, we demonstrated that the female promoting gene, CmACS11, represses the expression of the male promoting gene CmWIP1 via deposition of H3K27me3.ConclusionsOur findings reveal the organ-specific landscapes of H3K9ac and H3K27me3 in melon. Our results also provide evidence that the sex determination genes recruit histone modifiers to orchestrate unisexual flower development in monoecious species.

  6. Increasing Hermaphrodite Flowers using Plant Growth Regulators in Andromonoecious Jatropha curcas

    Directory of Open Access Journals (Sweden)

    DASUMIATI

    2014-09-01

    Full Text Available Jatropha curcas (JC is a crop with potential for use in biodiesel. Production of biodiesel requires plant seed as raw material, so the viability of JC for use in biodiesel will dependent greatly on the plant’s production of flowers. Generally, this plant is monoecious, meaning it has both male and female flowers. However, very rarely JC plants may be andromonoecious. Andromonoecious specimens of JC produce hermaphrodite and male flowers in the same plant. The number of hermaphrodite flowers per inflorescence is generally low compared to the number of male flowers. The aim of this study was to increase the proportion of hermaphrodite flowers by using plant growth regu- lators (PGRs in andromonoecious JC. Our experiment was conducted in Randomized Block Design (RBD with 9 treatments, namely kinetin, GA3, and IAA with concentrations of 0 ppm as a control, 50 and 100 ppm of each PGRs. The treatments were applied to stem cuttings from each plant and repeated 4 times. PGRs were applied by spraying the leaves within the buds of each plant. Applications took place weekly beginning when the plants entered flower initiating phase, until inflorescence produced. Observations were conducted during the treatment period (10 weeks. Results showed that plants treated with IAA, GA3, and kinetin at 50 and 100 ppm produced increased inflorescence per plant. The increases measured were 155.4 and 92.9% of (IAA, 120.4 and 151% (GA3, 96.6 and 51.7% (kinetin respectively. In addition, we found that application and GA3 at concentrations of 50 and 100 ppm, and kinetin at 50 ppm, increased the number of hermaphrodite flowers per inflorescence by 50%, and increased the number of hermaphrodite flowers per plant by 275.6 and 183.1% (IAA, 219.5 and 254.1% (GA3, 162.9 and 103.1% (kinetin respectively. As would be expected, the number of fruit per plant increased in those specimens treated with IAA, GA3, and kinetin at 50 and 100 ppm. The increases measured were 301.7 and 167

  7. Reproductive biology characteristic of Jatropha curcas (Euphorbiaceae

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    Xiu-Rong Wang

    2012-12-01

    Full Text Available Jatropha curcas belongs to family of Euphorbiaceae, and is an important biological tree species for diesel production. The current descriptions of the phenotypic traits for male and female flowers are not comprehensive and there have been no reports about the process of J. curcas from pollen germination on stigma to pollen tubes conducting fertilization after entering the ovary and ovule. To assess this, experiments were undertaken to study the reproductive biology characteristic of J. curcas in Guiyang Guizhou Province, China. Floral structure and pollen germination process were described in detail and the breeding system was determined. The results showed that flower of J. curcas was both unisexual and monoecious, with a flowering phase between April-November. Both female and male flowers have five petals in contorted arrangement and five calyxes in imbricated arrangement. Female flower originated from bisexual flower finally formed unisexual flowers as the stamen ceased growth in different period. The pistil had 3-5 styles, connected at base and separated into 3-5 stigmas on the top. Each stigma had 2-4 lobes. The styles were hollow. The pollen germinated on the surface of the stigma, is then transported via the vascular tissues, which was arranged in bundles, and finally channeled through the micropyle to enter the blastula. The pollen tube was shaped in a long uneven cylinder. The top end of it became swollen and formed a small round hole for the purpose of releasing sperm nuclei while the pollen tube itself was growing and extending. Estimation of out-crossing index and artificial pollination experiments indicated that J. curcas was capable of both self-pollination and cross-pollination. The germination speed of the pollen on the stigma did not differ so much between the one by self-pollination and the one by cross-pollination, and the pollen from the two different sources could both reach the ovary within one day. Both artificial

  8. Desempenho produtivo, partenocarpia e expressão sexual de linhagens de pepino caipira em ambiente protegido Yield, parthenocarpy and sexual expression of 'caipira' cucumber lines under protected cultivation

    Directory of Open Access Journals (Sweden)

    Amanda Regina Godoy

    2009-06-01

    linhagens principalmente devido ao tipo de fruto caipira mais próximo dos frutos comerciais.The yield capacity, parthenocarpy and sexual expression of 'caipira' cucumber lines were evaluated under protected cultivation. Yield capacity was evaluated in an experiment in randomized blocks design with 18 treatments (16 lines and two 'caipira' hybrids, Safira and Guarani, four replicates and five plants per plot, in a greenhouse with opened laterals to permit the entrance of pollinators. Sexual expression and parthenocarpy were evaluated in similar design, with 16 lines of SHS population (F2BC1 from the crossing between hybrids Safira and Hatem-beith alpha type and 19 of GH population (F2 from the crossing between hybrids Guarani and Hatem, but this experiment was set up in closed greenhouse, with anti-aphid net, avoiding the entrance of pollinators. Parthenocarpy was evaluated verifying fruit set in each line. Many lines were statistically similar to hybrids in yield capacity, but none was superior. Hybrids Safira and Guarani yielded 23.1 and 19.1 fruits plant-1, and 21.9 and 17.5 commercial fruits, respectively. Total and commercial weights plant-1 were respectively 3.8 and 3.6 kg for hybrid Safira and 2.9 and 2.7 kg for hybrid Guarani. Line SHS-2 presented good yield, similar to both hybrids, with light 'caipira' fruit type, besides parthenocarpy and gynoecious plants. All lines from population SHS have 'caipira' fruit type, but only five were parthenocarpic. In population GH, nine lines were parthenocarpic and ten have 'caipira' fruit type. Two lines from population SHS have only monoecious plants, with the others segregating to gynoecious and monoecious plants. In population GH, all plants were gynoecious. SHS population is more interesting to obtain lines because the 'caipira' fruit type is more similar to commercial fruits.

  9. 西双版纳地区钝叶榕的物候变化规律%Fruiting phenology of Ficus curtipes in Xishuangbanna

    Institute of Scientific and Technical Information of China (English)

    郭忠萍; Rhett-Daniel HARRISON; 彭艳琼; 杨大荣

    2014-01-01

    钝叶榕是西双版纳地区分布广泛的一种榕树(雌雄同株),具有较为特殊的传粉体系。近三年的野外物候观测数据显示,钝叶榕个体绝大多数每年结果1~2次,极少数一年结果3次,通常在雨季增加结果次数,出现树内异步的现象。钝叶榕结果树内同步,树间异步。钝叶榕雌花期和雄花期不能很好吻合,榕蜂系统在观测范围内处于不稳定状态,导致钝叶榕的雌花期和雄花期比其它种类的榕树长很多。结果表明:钝叶榕结果物候可能受相对湿度影响最大,但总体上其物候与温度、降雨量和相对湿度的相关关系未呈现明显的规律性。钝叶榕的物候变化应受其它气候因子作用或是各种生物因子和非生物因子共同作用的结果。物候和气候的现象十分复杂,进一步对钝叶榕物候的不同方面和各种气候因子进行相关性分析十分必要。%Phenology of plants and life history of pollinators should match and maintain their mutualism.Figs and their pollinating fig wasps form highly specific mutualism and co-adapt in the phenology and life history.Ficus cur-tipes is monoecious,which distributes widely in Xishuangbanna with special pollination system.Fig wasps on F .cur-tipes have been massively reported,however,fig trees are seldom concerned.In this paper,we address three ques-tions:(1)What are the fruiting patterns of female floral phase and male floral phase of F .curtipes ,do they match each other;(2)Are there any correlations between climatic factors and the phenolgy of F .curtipes ;(3)How can fruit-ing pattern affect fig-wasp system in F .curtipes Over 30 months,F .curtipes fruits once or twice,at most three times per year.F .curtipes occasionally fruit asynchronously within individual trees in rainy season,which may be a strategy for boosting pollinator populations.In certain months there is no overlap between male and female phases of Ficus curtipes within the

  10. 南瓜花发育过程中内源激素和多胺含量变化研究%Content changes of endogenous hormones and polyamine during flower development in pumpkin

    Institute of Scientific and Technical Information of China (English)

    杨贵先; 杨晓霞; 王洋洋; 徐文龙; 崔崇士; 屈淑平

    2016-01-01

    The female and male flowers in different development stages of subgynoecious pumpkin lines ‘2013‐12’ and monoecious lines‘9‐6’ were used as materials to test the content changes of five internal hormones and four polyamines .The results show that zeatin (ZT) content gradually reduces in male and female flowers along with the development of flower bud ,the ZT content in male flowers is higher than that in female flowers .IAA content in male flowers decreases firstly and then increases ,but IAA content in female flowers increases firstly and then decreases .Gibberellic acid (GA3 ) in the development of male and female flow‐ers shows a trend of gradual decline .Abscisic acid (ABA) content in male flowers shows the change trend of rise and decline ,the dynamics of ABA contents in the female flower buds show the change of rise ,decline and rise .Ethylene content gradually increa‐ses in female and female along with the development of flower bud ,and it is higher than that in female flowers .Spermidine (Spd) content is the highest ,followed by spermine (Spm) ,putrescine (Put) the lowest in the male and female flowers ,Spm and Spd content in male flowers along with flower development period always lower level ,Spm and Spd content in female flowers are high‐er than those in male flowers .%以南瓜强雌品系‘2013‐12’和强雄品系‘9‐6’为试材,研究南瓜雌、雄花发育过程中内源激素和多胺的变化。结果表明,玉米素(zeatin ,ZT)随南瓜雌雄花的发育逐渐降低,且雄花中ZT的含量高于雌花;南瓜雄花中生长素(IAA)含量呈现先上升、后下降的变化趋势,雌花中IAA含量呈现先下降、后上升的变化趋势;南瓜雌雄花发育过程中赤霉素(gibberellic acid ,GA3)均呈现逐渐下降的趋势;雄花脱落酸(abscisic acid ,ABA )含量呈现升-降的变化趋势,雌花ABA含量呈现升-降-升的规律;乙烯在南瓜花发育过程中

  11. Reprodução sexuada em musgos acrocárpicos do Estado de Pernambuco, Brasil Sexual reproduction in acrocarpous mosses of Pernambuco State, Brazil

    Directory of Open Access Journals (Sweden)

    Sylvia Mota de Oliveira

    1998-01-01

    Full Text Available A freqüência de reprodução sexuada através da produção de esporófito foi determinada para musgos acrocárpicos, coletados no Estado de Pernambuco e depositados no Herbário UFP. Cada exsicata foi observada ao estereomicroscópio para verificação da ocorrência e do estádio de desenvolvimento do esporófito. Às informações obtidas acrescentaram-se dados de coleta e outros específicos pesquisados em literatura. Examinaram-se 770 exsicatas, pertencentes a 11 famílias e 59 espécies. Destas, 26 são monóicas, 27 dióicas e as seis restantes têm sistema reprodutivo desconhecido. A ocorrência de esporófito por amostras foi de 3:1, de monóica em relação à dióica. Apresentaram esporófito 88% das espécies com maior riqueza de amostras, havendo tendência, entre as dióicas, de produção ocasional ou rara de esporófito. A análise do estádio de desenvolvimento dos esporófitos por ocasião da coleta demonstrou que a produção ocorre principalmente durante o período chuvoso. Confirma-se então a importância da umidade e da autofecundação na reprodução sexuada destes musgos.The frequency of sexual reproduction in acrocarpous mosses collected in Pernambuco State, and subsequently deposited in the UFP Herbarium, was determined based on sporophyte production. Each voucher was observed under a dissecting microscope for recording the presence of the sporophyte and its developmental stage. The data obtained from literature was also registered. 770 voucher, distributed in 11 families and 59 species, were examined. 26 species have a monoecious reproductive system, 27 a dioicous one, and the six remaining ones have an unknown breeding system. The rate of fruiting specimens was higher in monoicous (3:1 than dioicous ones. Sporophytes were found in 88% of the best represented species. The frequency of fruiting specimens of dioicous species is either occasional or rare. The analysis of the developmental stages of sporophyte

  12. 福州细叶榕传粉生物学%Pollination biology of Ficus microcarpa in Fuzhou

    Institute of Scientific and Technical Information of China (English)

    吴文珊; 张彦杰; 陈友铃; 严菊媛; 郑翠芳

    2013-01-01

    Ficus microcarpa, a common ornamental species in Fuzhou, was a kind of monoecious fig species, A total 85 F. microcarpa plants in Fuzhou were chosen to study their pollination biology. The syconium growth of F. microcarpa can be divided into five phases: pre-female phase, female phase, inter-floral phase, male-phase and post-floral phase. F. microcarpa has both long style and short style female flowers. The stigma is long and curved, independent from each other, and does not form joint stigma platform that benefits to fig wasps' pollination and spawning. Its male flower matures late. F. microcarpa can continuously produce the figs year-round. Fruiting peaks occur during April to August, and each tree can produce 1 -4 crops in a year. The growth duration of F, microcarpa syconia from pre-female phase to post-floral phase was closely associated with the hydrothermal conditions. In the dry and cold season, that is from October to March, figs grow slowly, and the developmental cycle usually lasts for 3 -6 months. However, in the wet and hot season, that is from April to September, figs grow faster, and the developmental cycle is finished in only 1-2 months The fig development is inter-tree and intra-tree asynchrony, and the sexual phase overlaps frequently. The foundress number of F. microcarpa during female phase is dominated by only 1-2 wasp, which makes the small and numerous syconia effectively obtain wasps, does not only significantly raise pollination efficiency of wasps, but also ensures high ratio of fruiting in syconia. This may be the result of co-evolution of the fig-wasp mutualism. Seventeen kinds of wasps were found in syconia of F. microcarpa in Fuzhou, and they belong to six families ( subfamily) of Chalcidoidea. Among them, Eupristina verticillata of Agaonidae was the only species-specific pollinator for F. microcarpa, and it dominated in the structure of wasp community. F. microcarpa had low seed output rate, with only 13.64% , probably due to the lack

  13. Evaluating Non-Linear Regression Models in Analysis of Persian Walnut Fruit Growth

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    I. Karamatlou

    2016-02-01

    Full Text Available Introduction: Persian walnut (Juglans regia L. is a large, wind-pollinated, monoecious, dichogamous, long lived, perennial tree cultivated for its high quality wood and nuts throughout the temperate regions of the world. Growth model methodology has been widely used in the modeling of plant growth. Mathematical models are important tools to study the plant growth and agricultural systems. These models can be applied for decision-making anddesigning management procedures in horticulture. Through growth analysis, planning for planting systems, fertilization, pruning operations, harvest time as well as obtaining economical yield can be more accessible.Non-linear models are more difficult to specify and estimate than linear models. This research was aimed to studynon-linear regression models based on data obtained from fruit weight, length and width. Selecting the best models which explain that fruit inherent growth pattern of Persian walnut was a further goal of this study. Materials and Methods: The experimental material comprising 14 Persian walnut genotypes propagated by seed collected from a walnut orchard in Golestan province, Minoudasht region, Iran, at latitude 37◦04’N; longitude 55◦32’E; altitude 1060 m, in a silt loam soil type. These genotypes were selected as a representative sampling of the many walnut genotypes available throughout the Northeastern Iran. The age range of walnut trees was 30 to 50 years. The annual mean temperature at the location is16.3◦C, with annual mean rainfall of 690 mm.The data used here is the average of walnut fresh fruit and measured withgram/millimeter/day in2011.According to the data distribution pattern, several equations have been proposed to describesigmoidal growth patterns. Here, we used double-sigmoid and logistic–monomolecular models to evaluate fruit growth based on fruit weight and4different regression models in cluding Richards, Gompertz, Logistic and Exponential growth for evaluation

  14. Reproductive biology characteristic of Jatropha curcas (Euphorbiaceae

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    Xiu-Rong Wang

    2012-12-01

    Full Text Available Jatropha curcas belongs to family of Euphorbiaceae, and is an important biological tree species for diesel production. The current descriptions of the phenotypic traits for male and female flowers are not comprehensive and there have been no reports about the process of J. curcas from pollen germination on stigma to pollen tubes conducting fertilization after entering the ovary and ovule. To assess this, experiments were undertaken to study the reproductive biology characteristic of J. curcas in Guiyang Guizhou Province, China. Floral structure and pollen germination process were described in detail and the breeding system was determined. The results showed that flower of J. curcas was both unisexual and monoecious, with a flowering phase between April-November. Both female and male flowers have five petals in contorted arrangement and five calyxes in imbricated arrangement. Female flower originated from bisexual flower finally formed unisexual flowers as the stamen ceased growth in different period. The pistil had 3-5 styles, connected at base and separated into 3-5 stigmas on the top. Each stigma had 2-4 lobes. The styles were hollow. The pollen germinated on the surface of the stigma, is then transported via the vascular tissues, which was arranged in bundles, and finally channeled through the micropyle to enter the blastula. The pollen tube was shaped in a long uneven cylinder. The top end of it became swollen and formed a small round hole for the purpose of releasing sperm nuclei while the pollen tube itself was growing and extending. Estimation of out-crossing index and artificial pollination experiments indicated that J. curcas was capable of both self-pollination and cross-pollination. The germination speed of the pollen on the stigma did not differ so much between the one by self-pollination and the one by cross-pollination, and the pollen from the two different sources could both reach the ovary within one day. Both artificial

  15. Biologia da polinização da palmeira tucumã (Astrocaryum vulgare Mart. em Belém, Pará, Brasil Pollination biology of fiber palm (Astrocaryum vulgare Mart. in Belém, Pará, Brazil

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    Maria do Socorro Padilha de Oliveira

    2003-09-01

    . Phenology, floral morphology, time of flowering, pollen viability, and floral visitors data were collected, in ten plants, from January to December/1997. This palm is arborescent, multicaule, monoecious with inflorescence involved by a bract woody covered by thorns and hundreds unisexual sessile flowers. The female flower is flanked by two male flowers forming the triads, and located in the base of the rachillae; cream and measure 5 to 10mm of length; campanular type with petals stuck to the stigma exposed. The male flowers is in larger amount, and measure from 2 to 4mm of length. The flowering and fruiting were registered in every period, with picks of March to July and December to March, respectively. The opening of bract and exposition of the inflorescence occurred mainly in the beginning of the morning and in the night, moment in that all the female flowers began the anthesis happening with stigma producing secretion viscous, and stay receptive for 24 at 36 hours. The male flowers, also, presented simultaneous anthesis, staying viable for 24 at 36 hours, but stayed in the rachillae for many days. Pollen viability was high in flower buds in the pre-anthesis and in the open flowers. The floral rewards were the pollen abundantly and stigmatic secretion. Several parts of the inflorescence, mainly the flowers, emitted strong scent. The floral visitors were insects, with predominance of beetles and bees. Therefore the fiber palm is protoginic with high pollen production and strong scent as the primary attractive and prevalently cantharophilic pollination.

  16. Pollination Biology of Ficus superba var. japonica in Fuzhou%福州笔管榕传粉生物学特征

    Institute of Scientific and Technical Information of China (English)

    郑翠芳; 陈晓倩; 陈友铃; 王爱芳; 王钊; 吴文珊

    2015-01-01

    Ficus superba var. japonica is one type of deciduous and monoecious trees,however its reproductive behavior is very little known. In this study,we investigated the reproductive biology of F. superba var. japonica in Fuzhou and the results are shown in the following. (1) F. superba var. japonica plants bear multiple batches of fruits (0 -5 crops) annually,among which the 1 or 2 batches per year is the most case. The fig developmental patterns exhibited synchronous intra-tree,asynchronous or synchronous inter-tree. There was no overlap of different developmental stages in trees. The fig developmental period was obviously affected by seasons. In the autumn and winter ( from November to the next February) when the sunshine period is short and the temperature is lower related to the rest of year,the fig developmental cycle usually lasted for 2 to 5 months;while in the spring and summer ( from March to October) ,the plant grows faster,and the fig developmental cycle was completed in only 1 to 2 months. 2) F. superba var. japonica plants renewed their leaves 1 to 2 times each year. Both defoliation and leaf-renewing peaked in early spring and late summer. The new leaves always started to emerge within 1 or 2 weeks after defoliation. It seems that the fig development and the growth of new leaves would be associated with defoliation of old leaves. The carbohydrates for fig production are provided by leaves through the process of photosynthesis. 3 ) The foundress of F. superba var. japonica during the female flowering phase was usually occupied by only 1 -3 wasps. Therefore,the large quantity of small-sized figs had chances to host sufficient pollinating wasps to ensure their development. This circumstance can also avoid the adverse consequences such as the wasp death and the low spawning efficiency caused by too many pollinators in the limited fig space. It was found that the pollinators that enter syconia all had to some degrees disability. 4) In the female phase