WorldWideScience

Sample records for cacti

  1. Matchings in hexagonal cacti

    Directory of Open Access Journals (Sweden)

    E. J. Farrell

    1987-06-01

    Full Text Available Explicit recurrences are derived for the matching polynomials of the basic types of hexagonal cacti, the linear cactus and the star cactus and also for an associated graph, called the hexagonal crown. Tables of the polynomials are given for each type of graph. Explicit formulae are then obtained for the number of defect-d matchings in the graphs, for various values of d. In particular, formulae are derived for the number of perfect matchings in all three types of graphs. Finally, results are given for the total number of matchings in the graphs.

  2. Independent sets in chain cacti

    CERN Document Server

    Sedlar, Jelena

    2011-01-01

    In this paper chain cacti are considered. First, for two specific classes of chain cacti (orto-chains and meta-chains of cycles with h vertices) the recurrence relation for independence polynomial is derived. That recurrence relation is then used in deriving explicit expressions for independence number and number of maximum independent sets for such chains. Also, the recurrence relation for total number of independent sets for such graphs is derived. Finaly, the proof is provided that orto-chains and meta-chains are the only extremal chain cacti with respect to total number of independent sets (orto-chains minimal and meta-chains maximal).

  3. Cacti and filtered distributive laws

    CERN Document Server

    Dotsenko, Vladimir

    2011-01-01

    Motivated by the second author's construction of a classifying space for the group of pure symmetric automorphisms of a free product, we introduce and study a family of topological operads, the operads of based cacti, defined for every pointed topological space $(Y,\\bullet)$. These operads also admit linear versions, which are defined for every augmented graded cocommutative coalgebra $C$. We show that the homology of the topological operad of based $Y$-cacti is the linear operad of based $H_*(Y)$-cacti. In addition, we show that for every coalgebra $C$ the operad of based $C$-cacti is Koszul. To prove the latter result, we use the criterion of Koszulness for operads due to the first author, utilising the notion of a filtered distributive law between two quadratic operads. We also present a new proof of that criterion which works over the ground field of arbitrary characteristic.

  4. The Great Cacti: Ethnobotany & Biogeography

    Directory of Open Access Journals (Sweden)

    David A. Hooper

    2010-08-01

    Full Text Available Review of The Great Cacti: Ethnobotany & Biogeography. David Yetman. 2007. The University of Arizona, Tucson. Pp. 320, 366 color photographs, 17 maps. $59.95 (cloth. ISBN 9780816524310.

  5. Tissue culture of ornamental cacti

    Directory of Open Access Journals (Sweden)

    Eugenio Pérez-Molphe-Balch

    2015-12-01

    Full Text Available Cacti species are plants that are well adapted to growing in arid and semiarid regions where the main problem is water availability. Cacti have developed a series of adaptations to cope with water scarcity, such as reduced leaf surface via morphological modifications including spines, cereous cuticles, extended root systems and stem tissue modifications to increase water storage, and crassulacean acid metabolism to reduce transpiration and water loss. Furthermore, seeds of these plants very often exhibit dormancy, a phenomenon that helps to prevent germination when the availability of water is reduced. In general, cactus species exhibit a low growth rate that makes their rapid propagation difficult. Cacti are much appreciated as ornamental plants due to their great variety and diversity of forms and their beautiful short-life flowers; however, due to difficulties in propagating them rapidly to meet market demand, they are very often over-collected in their natural habitats, which leads to numerous species being threatened, endangered or becoming extinct. Therefore, plant tissue culture techniques may facilitate their propagation over a shorter time period than conventional techniques used for commercial purposes; or may help to recover populations of endangered or threatened species for their re-introduction in the wild; or may also be of value to the preservation and conservation of the genetic resources of this important family. Herein we present the state-of-the-art of tissue culture techniques used for ornamental cacti and selected suggestions for solving a number of the problems faced by members of the Cactaceae family.

  6. Groups, cacti and framed little discs

    CERN Document Server

    Hepworth, Richard

    2010-01-01

    Let G be a topological group. Then the based loopspace of G is an algebra over the cacti operad, while the double loopspace of the classifying space of G is an algebra over the framed little discs operad. This paper shows that these two algebras are equivalent, in the sense that they are weakly equivalent E-algebras, where E is an operad weakly equivalent to both framed little discs and cacti. We recover the equivalence between cacti and framed little discs, and Menichi's isomorphism between the BV-algebras obtained by taking the homology of the loopspace of G and of the double loopspace of BG.

  7. Spectra of Husimi cacti: Exact results and applications

    Science.gov (United States)

    Galiceanu, Mircea; Blumen, Alexander

    2007-10-01

    Starting from exact relations for finite Husimi cacti we determine their complete spectra to very high accuracy. The Husimi cacti are dual structures to the dendrimers but, distinct from these, contain loops. Our solution makes use of a judicious analysis of the normal modes. Although close to those of dendrimers, the spectra of Husimi cacti differ. From the wealth of applications for measurable quantities which depend only on the spectra, we display for Husimi cacti the behavior of the fluorescence depolarization under quasiresonant Förster energy transfer.

  8. Decay of cacti and carbon cycling

    Science.gov (United States)

    Garvie, Laurence A. J.

    2006-03-01

    Cacti contain large quantities of Ca-oxalate biominerals, with C derived from atmospheric CO2. Their death releases these biominerals into the environment, which subsequently transform to calcite via a monohydrocalcite intermediate. Here, the fate of Ca-oxalates released by plants in arid environments is investigated. This novel and widespread form of biomineralization has unexpected consequences on C cycling and calcite accumulation in areas with large numbers of cacti. The magnitude of this mineralization is revealed by studying the large columnar cactus Carnegiea gigantea (Engelm.) Britton and Rose in southwestern Arizona (locally called the saguaro). A large C. gigantea contains on the order of 1×105 g of the Ca-oxalate weddellite—CaC2O4·2H2O. In areas with high C. gigantea density, there is an estimated 40 g Catm m-2 sequestered in Ca-oxalates. Following the death of the plant, the weddellite transforms to calcite on the order to 10-20 years. In areas with high saguaro density, there is an estimated release of up to 2.4 g calcite m-2 year-1 onto the desert soil. Similar transformation mechanisms occur with the Ca-oxalates that are abundant in the majority of cacti. Thus, the total atmospheric C returned to the soil of areas with a high number density of cacti is large, suggesting that there may be a significant long-term accumulation of atmospheric C in these soils derived from Ca-oxalate biominerals. These findings demonstrate that plant decay in arid environments may have locally significant impacts on the Ca and inorganic C cycles.

  9. Chain hexagonal cacti with the extremal eccentric distance sum.

    Science.gov (United States)

    Qu, Hui; Yu, Guihai

    2014-01-01

    Eccentric distance sum (EDS), which can predict biological and physical properties, is a topological index based on the eccentricity of a graph. In this paper we characterize the chain hexagonal cactus with the minimal and the maximal eccentric distance sum among all chain hexagonal cacti of length n, respectively. Moreover, we present exact formulas for EDS of two types of hexagonal cacti. PMID:24741365

  10. Topological Cacti: Visualizing Contour-based Statistics

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Gunther H.; Bremer, Peer-Timo; Pascucci, Valerio

    2011-05-26

    Contours, the connected components of level sets, play an important role in understanding the global structure of a scalar field. In particular their nestingbehavior and topology-often represented in form of a contour tree-have been used extensively for visualization and analysis. However, traditional contour trees onlyencode structural properties like number of contours or the nesting of contours, but little quantitative information such as volume or other statistics. Here we use thesegmentation implied by a contour tree to compute a large number of per-contour (interval) based statistics of both the function defining the contour tree as well asother co-located functions. We introduce a new visual metaphor for contour trees, called topological cacti, that extends the traditional toporrery display of acontour tree to display additional quantitative information as width of the cactus trunk and length of its spikes. We apply the new technique to scalar fields ofvarying dimension and different measures to demonstrate the effectiveness of the approach.

  11. Cacti supply limited nutrients to a desert rodent community.

    Science.gov (United States)

    Orr, Teri J; Newsome, Seth D; Wolf, Blair O

    2015-08-01

    In the Sonoran Desert, cacti represent a potentially important source of nutrients and water for consumers. Columnar cacti, in particular, produce a large pulse of flowers and succulent fruit during hot summer months. The importance of cactus stems, flowers and fruit to the small mammal community has not been quantified. We exploited natural variation in the carbon isotope (δ(13)C) values of cacti (CAM) versus C3 plants to quantify the relative use of these resources by a diverse desert small mammal community. We also estimated trophic level by measuring nitrogen isotope (δ(15)N) values. We hypothesized that (H1) granivorous heteromyids (kangaroo rats, pocket mice) would exploit the summer pulse of seeds and pulp; (H2) folivorous and omnivorous cactus mice, wood rats, and ground squirrels would exploit cacti stems year-round and seeds when available; and (H3) kangaroo rats and pocket mice would shift from seeds to insects during hot dry months. We found that heteromyids made minimal use of seeds during the period of heavy seed rain. Of the cricetids, only the folivore Neotoma albigula made continuous but highly variable use of cacti resources (annual mean = 32%, range 0-81%), whereas the omnivore Peromyscus eremicus ignored cacti except during the summer, when it exploited seeds and/or fruit pulp (June-July mean = 39%, range 20-64%). We also found little evidence for a shift to greater consumption of insects by heteromyids during the hot dry months. Overall, use of cactus resources by the small mammal community is very limited and highly variable among species. PMID:25842296

  12. Immediate allergic and nonallergic reactions to Christmas and Easter cacti

    DEFF Research Database (Denmark)

    Andersen, F; Bindslev-Jensen, C; Stahl Skov, P;

    1999-01-01

    tested; 58 of these were tested with HRT/Refix. Furthermore, 22 healthy controls were included and tested in vivo and in vitro. Cactus-related contact urticaria and/or rhinoconjunctivitis were reported by 37% of the cactus workers. Based on a combination of positive history, positive SPT, and positive...... HRT/ Refix to cactus, 8% of the cactus workers were allergic to cacti. No noncactus workers or controls were allergic to cacti by these criteria. Testing with fresh cactus material elicited positive SPT and negative HRT/Refix in 27 nursery workers and controls, of whom 12 had immediate-type skin and...

  13. Predation potential of Chilocorus cacti (Coleoptera: Coccinellidae) to the prickly pear cacti pest Dactylopius opuntiae (Hemiptera: Dactylopiidae).

    Science.gov (United States)

    Flores, A; Olvera, H; Rodríguez, S; Barranco, J

    2013-08-01

    Functional response of the predator Chilocorus cacti (Linnaeus) (Coleoptera: Coccinellidae) on five densities of Dactylopius opuntiae (Cockerell) (Hemiptera: Dactylopiidae) female adults was assessed under laboratory conditions. The searching efficiency of C. cacti significantly decreased as prey density increased. The logistic regression for the predator had a negative and significant linear parameter indicating a type II functional response. Non-linear regression for Holling predator equation estimated a handling time of 1.79 ± 0.129 h and attack rate coefficient of 0.1003 ± 0.030. Most of this handling time was because the predator spent a lot of time removing the waxy coating that protects adult females of D. opuntiae. Chilocorus cacti consumes females of D. opuntiae in their reproductive stage; therefore, it could be an effective natural enemy to suppress or regulate low density populations of D. opuntiae, preventing them to reach high densities. PMID:23949861

  14. Composition near the knee: results from the CACTI experiment

    Science.gov (United States)

    Yodh, Gaurang B.

    2003-07-01

    This paper presents a summary of the results the CACTI experiment, which studied the shape of Cherenkov lateral distributions of showers triggering the CYGNUS II air shower array at Los Alamos National Laboratory, to investigate the composition of cosmic rays in the PeV energy range.

  15. Composition near the knee: results from the CACTI experiment

    International Nuclear Information System (INIS)

    This paper presents a summary of the results the CACTI experiment, which studied the shape of Cherenkov lateral distributions of showers triggering the CYGNUS II air shower array at Los Alamos National Laboratory, to investigate the composition of cosmic rays in the PeV energy range

  16. Relaxation of polymers modeled by generalized Husimi cacti

    Science.gov (United States)

    Galiceanu, M.

    2010-07-01

    We focus on the generalized Husimi cacti, which are dual structures to the dendrimers but, distinct from the latter, contain loops. We determine their complete spectra by making use of the normal mode analysis. These spectra have been used in computing some physical quantities, such as the averaged monomer displacement and the mechanical relaxation moduli with its two components: the storage and the loss modulus. We also study the dynamics of Husimi cacti in solutions, introducing the hydrodynamic interactions in a preaveraged Oseen fashion, the so-called Zimm model. We observe that the relaxation quantities mentioned above do not scale, in the presence or in the absence of the hydrodynamic interactions. Our results show that all the relaxation forms depend on the number of monomers in the networks in the absence of the hydrodynamic interactions (Rouse model), while by taking into account the hydrodynamic interactions the results do not vary too much.

  17. Relaxation of polymers modeled by generalized Husimi cacti

    Energy Technology Data Exchange (ETDEWEB)

    Galiceanu, M, E-mail: mircea@fisica.ufpr.b [Departamento de Fisica, Universidade Federal do Parana, 81531-990 Curitiba (Brazil)

    2010-07-30

    We focus on the generalized Husimi cacti, which are dual structures to the dendrimers but, distinct from the latter, contain loops. We determine their complete spectra by making use of the normal mode analysis. These spectra have been used in computing some physical quantities, such as the averaged monomer displacement and the mechanical relaxation moduli with its two components: the storage and the loss modulus. We also study the dynamics of Husimi cacti in solutions, introducing the hydrodynamic interactions in a preaveraged Oseen fashion, the so-called Zimm model. We observe that the relaxation quantities mentioned above do not scale, in the presence or in the absence of the hydrodynamic interactions. Our results show that all the relaxation forms depend on the number of monomers in the networks in the absence of the hydrodynamic interactions (Rouse model), while by taking into account the hydrodynamic interactions the results do not vary too much.

  18. Relaxation of polymers modeled by generalized Husimi cacti

    International Nuclear Information System (INIS)

    We focus on the generalized Husimi cacti, which are dual structures to the dendrimers but, distinct from the latter, contain loops. We determine their complete spectra by making use of the normal mode analysis. These spectra have been used in computing some physical quantities, such as the averaged monomer displacement and the mechanical relaxation moduli with its two components: the storage and the loss modulus. We also study the dynamics of Husimi cacti in solutions, introducing the hydrodynamic interactions in a preaveraged Oseen fashion, the so-called Zimm model. We observe that the relaxation quantities mentioned above do not scale, in the presence or in the absence of the hydrodynamic interactions. Our results show that all the relaxation forms depend on the number of monomers in the networks in the absence of the hydrodynamic interactions (Rouse model), while by taking into account the hydrodynamic interactions the results do not vary too much.

  19. Vegetative propagation of cacti and other succulents in vitro.

    Science.gov (United States)

    Gratton, J; Fay, M F

    1990-01-01

    Maintenance of collections of succulent plants can be problematic, since many of these species are very susceptible to rots caused by bacteria and fungi. Rooting and establishment of cuttings can also be difficult. At Kew, methods for themicropropagation of cacti and other succulents have been developed over the last 10 yr. These have proved to be very useful for overcoming the problems mentioned above. PMID:21390609

  20. M2-Edge Colorings Of Cacti And Graph Joins

    Directory of Open Access Journals (Sweden)

    Czap Július

    2016-02-01

    Full Text Available An edge coloring φ of a graph G is called an M2-edge coloring if |φ(v| ≤ 2 for every vertex v of G, where φ(v is the set of colors of edges incident with v. Let 2(G denote the maximum number of colors used in an M2-edge coloring of G. In this paper we determine 2(G for trees, cacti, complete multipartite graphs and graph joins.

  1. Twitter Bootstrap and development of web repository for Cacti

    OpenAIRE

    Župec, Nejc

    2012-01-01

    For the purpose of this thesis a web repository Templator was developed. It enables to save graph and device templates which are used by Cacti, a system for network monitoring. With Templator all templates are stored in one place, they are standardized and sistematically organized. It consists of a search engine, a recommendation system, a manager for importing/exporting XML templates and enables users to login or register. The thesis also includes a basic overview how templates can be develo...

  2. Metaxenia in the Vine Cacti Hylocereus polyrhizus and Selenicereus spp.

    OpenAIRE

    MIZRAHI, YOSEF; MOUYAL, JOSEPH; NERD, AVINOAM; Sitrit, Yaron

    2004-01-01

    • Background and Aims Flowers of the vine cacti of the genera Hylocereus and Selenicereus grown in Israel must be hand pollinated due to self‐incompatibility and lack of efficient pollinators. In controlled pollination experiments, it was found that the time elapsed between pollination and ripening depends on the source of the pollen. Therefore a study was made of some effects of the pollen source on fruit development.

  3. Developmental Reaction Norms for Water Stressed Seedlings of Succulent Cacti

    OpenAIRE

    Rosas, Ulises; Zhou, Royce W.; Castillo, Guillermo; Collazo-Ortega, Margarita

    2012-01-01

    Succulent cacti are remarkable plants with capabilities to withstand long periods of drought. However, their adult success is contingent on the early seedling stages, when plants are highly susceptible to the environment. To better understand their early coping strategies in a challenging environment, two developmental aspects (anatomy and morphology) in Polaskia chichipe and Echinocactus platyacanthus were studied in the context of developmental reaction norms under drought conditions. The m...

  4. Dew harvesting efficiency of four species of cacti.

    Science.gov (United States)

    Malik, F T; Clement, R M; Gethin, D T; Beysens, D; Cohen, R E; Krawszik, W; Parker, A R

    2015-06-01

    Four species of cacti were chosen for this study: Copiapoa cinerea var. haseltoniana, Ferocactus wislizenii, Mammillaria columbiana subsp. yucatanensis and Parodia mammulosa. It has been reported that dew condenses on the spines of C. cinerea and that it does not on the spines of F. wislizenii, and our preliminary observations of M. columbiana and P. mammulosa revealed a potential for collecting dew water. This study found all four cacti to harvest dew on their stems and spines (albeit rarely on the spines of F. wislizenii). Dew harvesting experiments were carried out in the UK, recording an increase in cacti mass on dewy nights. By applying a ranking relative to a polymethyl methacrylate (Plexiglas) reference plate located nearby, it was found that C. cinerea collected the most airborne moisture followed by M. columbiana, P. mammulosa and F. wislizenii respectively, with mean efficiency ratio with respect to the Plexiglas reference of 3.48 ± 0.5, 2.44 ± 0.06, 1.81 ± 0.14 and 1.27 ± 0.49 on observed dewy nights. A maximum yield of normalized performance of 0.72 ± 0.006 l/m(-2) on one dewy night was recorded for C. cinerea. Removing the spines from M. columbiana was found to significantly decrease its dew harvesting efficiency. The spines of three of the species were found to be hydrophilic in nature, while F. wislizenii was hydrophobic; the stems of all four species were hydrophilic. The results of this study could be translated into designing a biomimetic water collecting device that utilizes cactus spines and their microstructures. PMID:25909346

  5. Feral livestock threatens landscapes dominated by columnar cacti

    Science.gov (United States)

    Malo, J. E.; Acebes, P.; Giannoni, S. M.; Traba, J.

    2011-05-01

    The introduction and naturalization of alien species represents a serious threat to many natural protected areas. One such case of worldwide concern is the impact of feral livestock on arid ecosystems. Damage suffered by Echinopsis (= Trichocereus) terscheckii dominating the landscape of rocky slopes was surveyed in seven locations within the Ischigualasto-Talampaya World Heritage Site (Argentina) by measuring the frequency, position on the plant and extent of damage. At the same time we employed transects to estimate the abundance of autochtonous and feral large herbivores ( Lama guanicoe, Bos taurus, Equus asinus) from their dung. Our results show relatively high damage levels (40-77% of individuals damaged, more than 5 dm 3 removed by plant in some sites), particularly within 0.50-1.75 m above the ground, showing herbivores to be the main responsible for them. We also found significant differences between sites in variables measuring damage level and in the intensity of use by the two feral livestock species but not by guanacos. The frequency of damaged cacti below 1.75 m (but not above) was significantly positively correlated among locations with the frequencies of cattle and donkey dung, and the damage suffered by individual cacti was also correlated with donkey and cattle dung in their surroundings after correcting for spatial effects. However, all correlations were non-significant in the case of guanacos. We conclude that the continued presence of feral livestock, particularly donkeys, leads to damages to columnar cacti with potential effects on their populations and the physiognomy of this protected landscape.

  6. The Cacti microbiome: interplay between habitat-filtering and host specificity

    OpenAIRE

    Citlali eFonseca-Garcia; Devin eColeman-Derr; Etzel eGarrido; Axel eVisel; Susannah Green Tringe; Laila Pamela Partida-Martinez

    2016-01-01

    Cactaceae represents one of the most species-rich families of succulent plants native to arid and semi-arid ecosystems, yet the associations Cacti establish with microorganisms and the rules governing microbial community assembly remain poorly understood. We analyzed the composition, diversity and factors influencing above- and below-ground bacterial, archaeal and fungal communities associated with two native and sympatric Cacti species: Myrtillocactus geometrizans and Opuntia robusta. Phylog...

  7. Functional trade-offs in succulent stems predict responses to climate change in columnar cacti.

    Science.gov (United States)

    Williams, David G; Hultine, Kevin R; Dettman, David L

    2014-07-01

    Columnar cacti occur naturally in many habitats and environments in the Americas but are conspicuously dominant in very dry desert regions. These majestic plants are widely regarded for their cultural, economic, and ecological value and, in many ecosystems, support highly diverse communities of pollinators, seed dispersers, and frugivores. Massive amounts of water and other resources stored in the succulent photosynthetic stems of these species confer a remarkable ability to grow and reproduce during intensely hot and dry periods. Yet many columnar cacti are potentially under severe threat from environmental global changes, including climate change and loss of habitat. Stems in columnar cacti and other cylindrical-stemmed cacti are morphologically diverse; stem volume-to-surface area ratio (V:S) across these taxa varies by almost two orders of magnitude. Intrinsic functional trade-offs are examined here across a broad range of V:S in species of columnar cacti. It is proposed that variation in photosynthetic gas exchange, growth, and response to stress is highly constrained by stem V:S, establishing a mechanistic framework for understanding the sensitivity of columnar cacti to climate change and drought. Specifically, species that develop stems with low V:S, and thus have little storage capacity, are expected to express high mass specific photosynthesis and growth rates under favourable conditions compared with species with high V:S. But the trade-off of having little storage capacity is that low V:S species are likely to be less tolerant of intense or long-duration drought compared with high V:S species. The application of stable isotope measurements of cactus spines as recorders of growth, water relations, and metabolic responses to the environment across species of columnar cacti that vary in V:S is also reviewed. Taken together, our approach provides a coherent theory and required set of observations needed for predicting the responses of columnar cacti to

  8. KNOWLEDGE AND CACTI USE IN FARM FAMILIES FROM COXCATLÁN, PUEBLA

    OpenAIRE

    Alma Delia Castillo-Campohermoso; Arturo López-Espinosa; Ignacio Ocampo-Fletes

    2010-01-01

    The arid and semiarid regions of Mexico are plants highly diverse ecosystems, with potential for sustainable use. The diversity of cacti has been used mainly in food, medicine and construction, generally at regional level. Unfortunately the inhabitants of the arid zones and have no current information about techniques for sustainable use and management of these resources, despite the knowledge we have of various species. In order to analyze the knowledge and use of local cacti made by residen...

  9. Gynogenesis in the vine cacti Hylocereus and Selenicereus (Cactaceae).

    Science.gov (United States)

    Garcia, Reinerio Benega; Cisneros, Aroldo; Schneider, Bert; Tel-Zur, Noemi

    2009-05-01

    Gynogenesis was investigated on the allotetraploid Selenicereus megalanthus and the diploid Hylocereus polyrhizus and Hylocereus undatus vine cactus species. Unpollinated ovules from developing flower buds containing microspores at middle uninucleate developmental stage were cultured on MS basal medium containing 2,4-D/TDZ with different sucrose concentrations. Ovule size increased under dark culture conditions in all the three species and the level of response was species and sucrose concentration dependent. The best responses were achieved in the two S. megalanthus accessions, E-123 and J-80, at 0.18 and 0.26 M sucrose. Only ovule enlargement was obtained in H. undatus and both ovule enlargement and callus were obtained in H. polyrhizus. Development in both species ceased and embryoids were not formed. Plant regeneration was directly and indirectly obtained in both S. megalanthus accessions. Ploidy level was determined for a total of 29 S. megalanthus gynogenic plants using flow cytometry: 15 were found to be dihaploid (plants with the gametophytic chromosome number) and the other 14 were found to have higher ploidy levels. This is the first report of successful gynogenesis in Cactaceae. The dihaploids of S. megalanthus successfully produced by ovule culture techniques opens new perspectives in vine cacti breeding. PMID:19266203

  10. The Cacti Microbiome: Interplay between Habitat-Filtering and Host-Specificity.

    Science.gov (United States)

    Fonseca-García, Citlali; Coleman-Derr, Devin; Garrido, Etzel; Visel, Axel; Tringe, Susannah G; Partida-Martínez, Laila P

    2016-01-01

    Cactaceae represents one of the most species-rich families of succulent plants native to arid and semi-arid ecosystems, yet the associations Cacti establish with microorganisms and the rules governing microbial community assembly remain poorly understood. We analyzed the composition, diversity, and factors influencing above- and below-ground bacterial, archaeal, and fungal communities associated with two native and sympatric Cacti species: Myrtillocactus geometrizans and Opuntia robusta. Phylogenetic profiling showed that the composition and assembly of microbial communities associated with Cacti were primarily influenced by the plant compartment; plant species, site, and season played only a minor role. Remarkably, bacterial, and archaeal diversity was higher in the phyllosphere than in the rhizosphere of Cacti, while the opposite was true for fungi. Semi-arid soils exhibited the highest levels of microbial diversity whereas the stem endosphere the lowest. Despite their taxonomic distance, M. geometrizans and O. robusta shared most microbial taxa in all analyzed compartments. Influence of the plant host did only play a larger role in the fungal communities of the stem endosphere. These results suggest that fungi establish specific interactions with their host plant inside the stem, whereas microbial communities in the other plant compartments may play similar functional roles in these two species. Biochemical and molecular characterization of seed-borne bacteria of Cacti supports the idea that these microbial symbionts may be vertically inherited and could promote plant growth and drought tolerance for the fitness of the Cacti holobiont. We envision this knowledge will help improve and sustain agriculture in arid and semi-arid regions of the world. PMID:26904020

  11. The Cacti microbiome imterplay between habitat-filtering and host -specificity

    Science.gov (United States)

    The main focus of this research was to generate an holistic baseline of the associations Cacti establish with prokaryotes and fungi in the bulk and proximal soil (the soils), the rhizosphere and the phyllosphere (the episphere), as well as in the root and stem endosphere (the endosphere) through phy...

  12. Development of a Multiplex PCR Method to Detect Fungal Pathogens for Quarantine on Exported Cacti.

    Science.gov (United States)

    Cho, Hyun Ji; Hong, Seong Won; Kim, Hyun-Ju; Kwak, Youn-Sig

    2016-02-01

    Major diseases in grafted cacti have been reported and Fusarium oxysporum, Bipolaris cactivora, Phytophthora spp. and Collectotrichum spp. are known as causal pathogens. These pathogens can lead to plant death after infection. Therefore, some European countries have quarantined imported cacti that are infected with specific fungal pathogens. Consequently, we developed PCR detection methods to identify four quarantined fungal pathogens and reduce export rejection rates of Korean grafted cacti. The pathogen specific primer sets F.oF-F.oR, B.CF-B.CR, P.nF-P.nR, and P.cF-P.CR were tested for F. oxysporum, B. cactivora, P. nicotinae, and P. cactorum, respectively. The F.oF-F.oR primer set was designed from the Fusarium ITS region; the B.CF-B.CR and P.nF-P.nR primers respectively from Bipolaris and Phytophthora ITS1; and the P.cF-P.CR primer set from the Ypt1protein gene region. The quarantine fungal pathogen primer pairs were amplified to the specific number of base pairs in each of the following fungal pathogens: 210-bp (F. oxysporum), 510-bp (B. cactivora), 313-bp (P. nicotinae), and 447-bp (P. cactorum). The detection limit for the mono- and multiplex PCR primer sets was 0.1 ng of template DNA under in vitro conditions. Therefore, each primer set successfully diagnosed contamination of quarantine pathogens in export grafted cacti. Consequently, our methodology is a viable tool to screen contamination of the fungal pathogen in exported grafted cacti. PMID:26889115

  13. Cytology and mating systems in the climbing cacti Hylocereus and Selenicereus.

    Science.gov (United States)

    Lichtenzveig, J; Abbo, S; Nerd, A; Tel-Zur, N; Mizrahi, Y

    2000-07-01

    Chromosome numbers and meiotic behavior are reported for the climbing cacti species Hylocereus undatus, Hylocereus polyrhizus, and Selenicereus megalanthus. The Hylocereus spp. are diploid (2n = 22), while S. megalanthus is a tetraploid (2n = 44). Irregular chromosome disjunction at anaphase I in pollen mother cells of S. megalanthus is probably the major cause of its reduced pollen viability and may contribute to low seed set, low number of viable seeds and, consequently, low fruit mass. A pollination study confirmed self-incompatibility in H. polyrhizus and a weakened incompatibility reaction in H. undatus and S. megalanthus. Major crossability barriers do not exist between the Hylocereus spp. investigated. Reciprocal intergeneric crosses were successful between Hylocereus spp. and S. megalanthus, suggesting that an Hylocereus sp. might be one of the diploid progenitors of the tetraploid S. megalanthus. The implications of the results on cacti nomenclature and systematics are briefly discussed. PMID:10898783

  14. Descripción de los estados adultos e inmaduros y aspectos bioecológicos de Heterothrips cacti (Thysanoptera: Heterothripidae Description of adult and immature stages and bioecological aspects of Heterothrips cacti (Thysanoptera: Heterothripidae

    Directory of Open Access Journals (Sweden)

    María I. Zamar

    2011-06-01

    Full Text Available Se describen e ilustran los estados inmaduros de Heterothrips cacti Hood y se discuten las características biológicas y ecológicas de esta especie en las zonas semiáridas y de altura de Jujuy (Argentina. Los muestreos de frecuencia quincenal se realizaron en San Pedrito durante el período de floración de Opuntia sulphurea var. hildmannii en la temporada 2006-2007. La muestra consistió en cinco flores tomadas al azar de cada condición de evolución de las mismas. Para conocer las plantas hospedadoras y la distribución de H. cacti, se realizaron muestreos periódicos de la vegetación silvestre en la Prepuna y Puna de Jujuy. Los estudios biológicos se llevaron a cabo en el laboratorio, acondicionando flores de O. sulphurea con huevos de H. cacti en cajas de cría, para controlar la evolución del ciclo de vida. Heterothrips cacti es una especie antófila, oligófaga asociada a cactáceas, de amplia distribución en la Prepuna y Puna jujeñas. La biología de H. cacti está correlacionada con la de su planta hospedadora, O. sulphurea que presenta dos generaciones al año. Asimismo, el ciclo de vida está asociado con la evolución de la flor de la cactácea. El tiempo de desarrollo de los estados inmaduros de la primera y segunda generación fue de 45 ± 1.5 días y 287 ±3 días respectivamente. El estadio de desarrollo por el que la especie atraviesa el período entre floraciones es larva II quiescente, envuelta en un capullo de seda en el suelo. A 5 ºC y 0 hs luz se inhibe el estado de quiescencia de H. cacti. Se registró la incidencia de Ceranisus sp. parasitoide larvi-pupal durante la segunda generación de H. cacti.The immature stages of Heterothrips cacti Hood are described and illustrated and the biological and ecological features of this species in semi arid and high elevation zones of Jujuy province, Argentina, are discussed. Samplings were carried out every fifteen days in San Pedrito during the Opuntia sulphurea var

  15. CACTI: free, open-source software for the sequential coding of behavioral interactions.

    Directory of Open Access Journals (Sweden)

    Lisa H Glynn

    Full Text Available The sequential analysis of client and clinician speech in psychotherapy sessions can help to identify and characterize potential mechanisms of treatment and behavior change. Previous studies required coding systems that were time-consuming, expensive, and error-prone. Existing software can be expensive and inflexible, and furthermore, no single package allows for pre-parsing, sequential coding, and assignment of global ratings. We developed a free, open-source, and adaptable program to meet these needs: The CASAA Application for Coding Treatment Interactions (CACTI. Without transcripts, CACTI facilitates the real-time sequential coding of behavioral interactions using WAV-format audio files. Most elements of the interface are user-modifiable through a simple XML file, and can be further adapted using Java through the terms of the GNU Public License. Coding with this software yields interrater reliabilities comparable to previous methods, but at greatly reduced time and expense. CACTI is a flexible research tool that can simplify psychotherapy process research, and has the potential to contribute to the improvement of treatment content and delivery.

  16. CACTI: free, open-source software for the sequential coding of behavioral interactions.

    Science.gov (United States)

    Glynn, Lisa H; Hallgren, Kevin A; Houck, Jon M; Moyers, Theresa B

    2012-01-01

    The sequential analysis of client and clinician speech in psychotherapy sessions can help to identify and characterize potential mechanisms of treatment and behavior change. Previous studies required coding systems that were time-consuming, expensive, and error-prone. Existing software can be expensive and inflexible, and furthermore, no single package allows for pre-parsing, sequential coding, and assignment of global ratings. We developed a free, open-source, and adaptable program to meet these needs: The CASAA Application for Coding Treatment Interactions (CACTI). Without transcripts, CACTI facilitates the real-time sequential coding of behavioral interactions using WAV-format audio files. Most elements of the interface are user-modifiable through a simple XML file, and can be further adapted using Java through the terms of the GNU Public License. Coding with this software yields interrater reliabilities comparable to previous methods, but at greatly reduced time and expense. CACTI is a flexible research tool that can simplify psychotherapy process research, and has the potential to contribute to the improvement of treatment content and delivery. PMID:22815713

  17. Analysis of form and function in North American columnar cacti (tribe Pachycereeae).

    Science.gov (United States)

    Cornejo, D; Simpson, B

    1997-11-01

    Simple and multivariate linear models were used to demonstrate the influence of mechanical design and climate on stem morphology and branching architecture in 25 species of North American columnar cacti. The effect of phyletic inertia was tested by the method of independent contrasts. Stem girth was found to increase significantly slower with increased height within taxa (cross-sectional stem area ;ps [plant height] 0.603), than across taxon (cross-sectional stem area ;ps [plant height] 1.451). Juveniles are shown to be mechanically overbuilt and subsequently grow into more slender adult forms determined in part by structural limitations and the optimization of other stem functions. We make a structural analogy of relatively rigid columnar cacti to concrete columns and compare plants and models with similar growth forms lacking woody skeletons (barrel cacti). Taxa with woody support achieved a surface-to-volume ratio six times greater than taxa without woody support. Across taxon, cooler winter temperatures were associated with larger stem girths, and greater annual precipitation was associated with less frequent branching. The relationship between total plant surface and volume approaches isometry within taxa, but across taxon average individuals are scaled replicates. We hypothesize that architecture and average plant height are adjusted, in an evolutionary sense, to maintain geometric similitude between surface and volume along a climatic gradient. PMID:21708554

  18. KNOWLEDGE AND CACTI USE IN FARM FAMILIES FROM COXCATLÁN, PUEBLA

    Directory of Open Access Journals (Sweden)

    Alma Delia Castillo-Campohermoso

    2010-09-01

    Full Text Available The arid and semiarid regions of Mexico are plants highly diverse ecosystems, with potential for sustainable use. The diversity of cacti has been used mainly in food, medicine and construction, generally at regional level. Unfortunately the inhabitants of the arid zones and have no current information about techniques for sustainable use and management of these resources, despite the knowledge we have of various species. In order to analyze the knowledge and use of local cacti made by residents, this research was conducted in Coxcatlán community, a place that still has a great variety of cactus. We interviewed 61 women selected through random sampling and direct observation to record the knowledge and use of species that persist in Coxcatlán. However environmental degradation and loss of species associated with the current environmental crisis, stemming mainly from the practices and values of modern industrial society (Rozzi, et al., 2001, Coxcatlán there are various species of cacti are used by local people for food, ornamental and medicine. However, it is an extractive activity and there is no proper management, which favors its probable extinction.

  19. Microscale Mechanism of Age Dependent Wetting Properties of Prickly Pear Cacti (Opuntia).

    Science.gov (United States)

    Rykaczewski, Konrad; Jordan, Jacob S; Linder, Rubin; Woods, Erik T; Sun, Xiaoda; Kemme, Nicholas; Manning, Kenneth C; Cherry, Brian R; Yarger, Jeffery L; Majure, Lucas C

    2016-09-13

    Cacti thrive in xeric environments through specialized water storage and collection tactics such as a shallow, widespread root system that maximizes rainwater absorption and spines adapted for fog droplet collection. However, in many cacti, the epidermis, not the spines, dominates the exterior surface area. Yet, little attention has been dedicated to studying interactions of the cactus epidermis with water drops. Surprisingly, the epidermis of plants in the genus Opuntia, also known as prickly pear cacti, has water-repelling characteristics. In this work, we report that surface properties of cladodes of 25 taxa of Opuntia grown in an arid Sonoran climate switch from water-repelling to superwetting under water impact over the span of a single season. We show that the old cladode surfaces are not superhydrophilic, but have nearly vanishing receding contact angle. We study water drop interactions with, as well as nano/microscale topology and chemistry of, the new and old cladodes of two Opuntia species and use this information to uncover the microscopic mechanism underlying this phenomenon. We demonstrate that composition of extracted wax and its contact angle do not change significantly with time. Instead, we show that the reported age dependent wetting behavior primarily stems from pinning of the receding contact line along multilayer surface microcracks in the epicuticular wax that expose the underlying highly hydrophilic layers. PMID:27537082

  20. Phyllotactic spectra in cacti: Mammilaria species and some genera from Rebutia group

    Directory of Open Access Journals (Sweden)

    Edyta Gola

    2014-02-01

    Full Text Available Phyllotaxis of globular or hemispheric cacti from Mammillaria genus and from Rebutia group shows the significant differences between the two groups. An extremely wide spectrum of phyllotaxis with many infrequent patterns has been found in Rebutia group while in Mammilluria genus it appears to be quite narrow with the main Fibonacci pattern dominant. Therefore one of possible factors responsible for these differences might be a genetic one. Ontogenetic transformations of phyllotaxis both continuous (quantitative and discontinuous (qualitative have been found in studied cacti. These developmental events together with dichotomy frequently occurring in some taxa increase the level of phyllotaxis diversity. As more than one expression of the pattern occurred due to continuous transformations in many studied cacti - the numbers of opposite spirals can no longer be treated as a feature of the diagnostic value in cactus taxonomy. Because of intense developmental changes significant is rather a range of phyllotaxis diversity (phyllotactic spectrum than a single pattern or its expression in a given taxon.

  1. Stable Isotopic Variations in Columnar Cacti: are Responses to Climate Recorded in Spines?

    Science.gov (United States)

    English, N. B.; Dettman, D. L.; Williams, D. G.

    2004-12-01

    The behavior of the North American monsoon (NAM), particularly with respect to times of continental drought and its relationship to the Pacific-North American (PNA) teleconnection pattern and the El Nino/Southern Oscillation (ENSO) is of great interest to paleoclimatologists and water managers. Long-term instrumental precipitation and tree ring records in the southwestern United States and northwestern Mexico at low elevations are sparse and this has hindered research on NAM variability at interannual timescales. Saguaro cacti (Carnegiea gigantea) and other columnar cacti in North and South America are long-lived and have the potential to record climate variability on land with high temporal and spatial resolution. The vertical sequence of spines on the saguaro's exterior represents a high resolution (4 to 6 per year), and long (over 150 years) record of environmental change. We present results from an experiment where we tracked the oxygen isotopic values in the source waters, stem tissue waters and spine tissue for three treatments over the course of three months. These data are then compared to a previously developed mechanistic model of isotopic variation that reflects the physiological responses of Saguaro to climate variation over seasonal to century long time-scales. We also present the rationale for a new method to determine the growth rate of columnar cacti using the radiocarbon bomb spike. Our measurements reveal that oxygen and hydrogen isotopic variation among the sequentially produced and persistent spines covering the saguaro body record fluctuations in saguaro water balance. The model successfully predicts isotopic variation in spines and constrains controlling variables, yielding a powerful and high-resolution stable isotope index of water stress in the low desert. The development and refinement of an isotopic model for saguaro will serve as the basis for models applied to other species of columnar cacti in North and South America. The role of the

  2. Screening of Brazilian cacti rhizobacteria for plant growth promotion under drought.

    Science.gov (United States)

    Kavamura, Vanessa Nessner; Santos, Suikinai Nobre; Silva, João Luiz da; Parma, Márcia Maria; Avila, Luciana Aparecida; Visconti, Alexandre; Zucchi, Tiago Domingues; Taketani, Rodrigo Gouvêa; Andreote, Fernando Dini; Melo, Itamar Soares de

    2013-05-01

    Drought is one of the major problems worldwide. The search for new and efficient microorganisms, from unexplored environments, to be used in association with plants to alleviate the negative effects imposed by water stress, is an interesting alternative. Thus, cacti-associated bacteria from the Brazilian semi-arid region were isolated based on their ability to grow in medium with reduced water availability. Strains were tested for the production of exopolysaccharides (EPS), as well as in vitro plant growth promotion traits. A great proportion of the isolates belong to the genus Bacillus. From a total of forty-eight bacteria, 65% were able to grow in medium with reduced water availability (0.919Aw), exopolysaccharide production was observed for 65% of the strains. The production of indole acetic acid (IAA) exceeding 51μgmL(-1) was observed for 4% and the high solubilization of Ca-P was verified for 6% of the isolates. No strain was able to produce hydrogen cyanide (HCN), 71% produced ammonia and 79% showed a halo of carboxymethyl cellulose (CMC) degradation. Zea mays L. growth promotion under water stress (30% of field capacity) was achieved by two strains of Bacillus spp. This is the first report to describe cacti-associated bacteria from Brazilian semi-arid with plant growth-promoting abilities. PMID:23279812

  3. Seasonal changes in assimilation for Saguaro cacti (Carnegiea gigantean) corresponding to height and aspect in the Sonoran Desert

    Science.gov (United States)

    Bronson, D. R.; Dettman, D. L.; English, N. B.; Williams, D. G.

    2008-12-01

    The saguaro cactus is a long lived desert columnar cactus that is considered a foundation species of the Sonoran Desert due to its highly depended upon fruits, seeds and flowers. Surprisingly, little is known about the physiology of this ecologically important species. Recent global climate models have predicted changes both in the spatial and temporal distribution of precipitation in America's deserts over the next 50 to 100 years, however do to the lack of physiological data for the saguaro cacti it is uncertain how saguaros will respond to the predicted climate changes. The goal of this study was to measure CO2 flux from the saguaro cacti to explain changes in seasonal variation, vertical height, and aspect. The study site is located at the Desert Laboratory in Tucson, Arizona. Ten cacti were used for diurnal gas exchange measurements at four time periods during 2008 to capture pre-monsoon, monsoon and post-monsoon events. The results of this study will help further the understanding of how climate changes will affect the health of the saguaro cacti.

  4. Functional morphology and biomechanics of branch–stem junctions in columnar cacti

    Science.gov (United States)

    Schwager, Hannes; Masselter, Tom; Speck, Thomas; Neinhuis, Christoph

    2013-01-01

    Branching in columnar cacti features morphological and anatomical characteristics specific to the subfamily Cactoideae. The most conspicuous features are the pronounced constrictions at the branch–stem junctions, which are also present in the lignified vascular structures within the succulent cortex. Based on finite-element analyses of ramification models, we demonstrate that these indentations in the region of high flexural and torsional stresses are not regions of structural weakness (e.g. allowing vegetative propagation). On the contrary, they can be regarded as anatomical adaptations to increase the stability by fine-tuning the stress state and stress directions in the junction along prevalent fibre directions. Biomimetic adaptations improving the functionality of ramifications in technical components, inspired, in particular, by the fine-tuned geometrical shape and arrangement of lignified strengthening tissues of biological role models, might contribute to the development of alternative concepts for branched fibre-reinforced composite structures within a limited design space. PMID:24132310

  5. Functional morphology and biomechanics of branch-stem junctions in columnar cacti.

    Science.gov (United States)

    Schwager, Hannes; Masselter, Tom; Speck, Thomas; Neinhuis, Christoph

    2013-12-01

    Branching in columnar cacti features morphological and anatomical characteristics specific to the subfamily Cactoideae. The most conspicuous features are the pronounced constrictions at the branch-stem junctions, which are also present in the lignified vascular structures within the succulent cortex. Based on finite-element analyses of ramification models, we demonstrate that these indentations in the region of high flexural and torsional stresses are not regions of structural weakness (e.g. allowing vegetative propagation). On the contrary, they can be regarded as anatomical adaptations to increase the stability by fine-tuning the stress state and stress directions in the junction along prevalent fibre directions. Biomimetic adaptations improving the functionality of ramifications in technical components, inspired, in particular, by the fine-tuned geometrical shape and arrangement of lignified strengthening tissues of biological role models, might contribute to the development of alternative concepts for branched fibre-reinforced composite structures within a limited design space. PMID:24132310

  6. Alternative Proofs on the Indices of Cacti and Unicyclic Graphs with $n$ Vertices

    CERN Document Server

    Mallik, Sudipta

    2011-01-01

    Let $H_n$ be the cactus obtained from the star $K_{1,n-1}$ by adding $\\lfloor \\frac{n-1}{2}\\rfloor$ independent edges between pairs of pendant vertices. Let $K_{1,n-1}^+$ be the unicyclic graph obtained from the star $K_{1,n-1}$ by appending one edge. In this paper we give alternative proofs of the following results: Among all cacti with $n$ vertices, $H_n$ is the unique cactus whose spectral radius is maximal, and among all unicyclic graphs with $n$ vertices, $K_{1,n-1}^+$ is the unique unicyclic graph whose spectral radius is maximal. We also prove that among all odd-cycle graphs with $n$ vertices, $H_n$ is the unique odd-cycle graph whose spectral radius is maximal.

  7. Population genetics and phylogenetic relationships of beetles (Coleoptera: Histeridae and Staphylinidae) from the Sonoran Desert associated with rotting columnar cacti.

    Science.gov (United States)

    Pfeiler, Edward; Johnson, Sarah; Richmond, Maxi Polihronakis; Markow, Therese A

    2013-12-01

    Dozens of arthropod species are known to feed and breed in the necrotic tissues (rots) of columnar cacti in the Sonoran Desert. Because the necrotic patches are ephemeral, the associated arthropods must continually disperse to new cacti and therefore the populations of any given species are expected to show very little local genetic differentiation. While this has been found to be true for the cactophilic Drosophila, the evolutionary histories and characteristics of other arthropods inhabiting the same necrotic patches, especially the beetles, have yet to be examined. Here we used nucleotide sequence data from segments of the mitochondrial 16S rRNA and cytochrome c oxidase subunit I (COI) genes to examine population structure and demographic history of three sympatric beetle species (Coleoptera: Histeridae and Staphylinidae) collected on senita cactus (Lophocereus schottii) from six widely-separated localities on the Baja California peninsula of northwestern Mexico. Two histerids, Iliotona beyeri and Carcinops gilensis, and an unidentified staphylinid, Belonuchus sp., showed little or no population structure over a broad geographic area on the peninsula, consistent with the prediction that these beetles should show high dispersal ability. Demographic tests revealed varying levels of historical population expansion among the beetle species analyzed, which are discussed in light of their ecologies and concurrent biogeographic events. Additionally, phylogenetic analyses of COI sequences in Carcinops collected on a variety of columnar cacti from both peninsular and mainland Mexico localities revealed several species-level partitions, including a putative undescribed peninsular species that occurred sympatrically with C. gilensis on senita. PMID:23948866

  8. Local knowledge about cacti in rural communities in the mesoregion of Paraíba State (Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Nayze de Almeida Marreiros

    2012-09-01

    Full Text Available The goal of this study was to record the uses and knowledge of cacti in the rural communities of Barroquinha and Besouro, in the municipality of Lagoa, in Paraíba, Brazil. Semi-structured interviews were conducted with 52 informants (men and women. The cacti cited were organized into eight categories of use. Five species were identified in the communities: Cereus jamacaru DC., Melocactus sp., Pilosocereus chrysostele (Vaupel Byles & G. D. Rowley, Nopalea cochenillifera (L. Salm-Dyck and Pilosocereus gounellei (F.A.C. Weber Byles & Rowley. We registered 201 citations of use in Barroquinha, which were placed in seven categories, and 76 citations in Besouro, which were placed in eight categories. In both communities, C. jamacaru was the most used specie and forage was the most common category of use. Within the communities, the menand women had similar knowledge about these plants. In relation to the transmission of knowledge, there was a predominance of a vertical transmission, from parents to children. Based on the categories applied to the species, the various uses recorded show that these cacti are important to the Besouro and Barroquinha communities.

  9. Variation in the distribution of four cacti species due to climate change in Chihuahua, Mexico.

    Science.gov (United States)

    Cortes, Leonor; Domínguez, Irma; Lebgue, Toutcha; Viramontes, Oscar; Melgoza, Alicia; Pinedo, Carmelo; Camarillo, Javier

    2014-01-01

    This study is about four cacti species in the state of Chihuahua, (Coryphantha macromeris, Mammillaria lasiacantha, Echinocereus dasyacanthus and Ferocactus wislizenii). Geographic distribution was inferred with MaxEnt. Projection was estimated under three scenarios simulated from IPCC (A2, B1 and A1B) and four periods (2000, 2020, 2050 and 2080) with 19 climatic variables. MaxEnt projects a species decrease in 2020 under scenario A2, increasing in the following years. In 2080 all species, except E. dasyacanthus, will occupy a larger area than their current one. Scenario B1 projected for 2050 a decrease for all species, and in 2080 all species except E. dasyacanthus will increase their area. With A1B, C. macromeris decreases 27% from 2020 to 2050. E. dasyacanthus increases from 2020 to 2050 and decreases 73% from 2020 to 2080. M. lasiacantha decreases 13% from 2020 to 2080 and F. wislizenii will increase 13% from 2020 to 2080. Some species will remain stable on their areas despite climate changes, and other species may be affected under the conditions of the A1B scenario. It is important to continue with studies which give a broader perspective about the consequences of climate change, thus enabling decision-making about resource management. PMID:24368429

  10. Variation in the Distribution of Four Cacti Species Due to Climate Change in Chihuahua, Mexico

    Directory of Open Access Journals (Sweden)

    Leonor Cortes

    2013-12-01

    Full Text Available This study is about four cacti species in the state of Chihuahua, (Coryphantha macromeris, Mammillaria lasiacantha, Echinocereus dasyacanthus and Ferocactus wislizenii. Geographic distribution was inferred with MaxEnt. Projection was estimated under three scenarios simulated from IPCC (A2, B1 and A1B and four periods (2000, 2020, 2050 and 2080 with 19 climatic variables. MaxEnt projects a species decrease in 2020 under scenario A2, increasing in the following years. In 2080 all species, except E. dasyacanthus, will occupy a larger area than their current one. Scenario B1 projected for 2050 a decrease for all species, and in 2080 all species except E. dasyacanthus will increase their area. With A1B, C. macromeris decreases 27% from 2020 to 2050. E. dasyacanthus increases from 2020 to 2050 and decreases 73% from 2020 to 2080. M. lasiacantha decreases 13% from 2020 to 2080 and F. wislizenii will increase 13% from 2020 to 2080. Some species will remain stable on their areas despite climate changes, and other species may be affected under the conditions of the A1B scenario. It is important to continue with studies which give a broader perspective about the consequences of climate change, thus enabling decision-making about resource management.

  11. Use of cacti as heat sources by thermoregulating Mabuya agilis (Raddi and Mabuya macrorhyncha Hoge (Lacertflia, Scincidae in two restinga habitats in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Davor Vrcibradic

    2002-03-01

    Full Text Available Lizards may benefit from gain of heat from contact with the substrate via conduction. In this study, evidence that the lizards Mabuya agilis (Raddi, 1823 and Mabuya macrorhynclui Hoge, 1946 (Scincidae inhabiting two restinga habitats in southeastern Brazil (Grussaf, Rio de Janeiro and Praia das Neves, Espfrito Santo, may shift microhabitat preferences along the day, and that such shifts may be related to the use of cacti surfaces as direct sources of heat is presented. For both species, body temperature (Tb was always significantly correlated (p < 0,05 with air temperature (Ta. Tb was significantly correlated (p < 0,0.5 with substrate temperature (Ts for M. agilis collected on cacti, but not for specimens collected on the ground. For M. macrorhyncha collected on cacti, both Ta and Ts were more important in conjunction than separately, in explaining lizard Tb. Use of cacti as perches by M. agilis was more frequent during late afternoon when environmental temperatures are declining, but such a trend was not evident for M. macrorhynclui. We suggest that the use of cacti as direct heat sources may be more evident in the ground-dwelling M. agilis than in the scansorial M. macrorhynclui.

  12. Descripción de los estados adultos e inmaduros y aspectos bioecológicos de Heterothrips cacti (Thysanoptera: Heterothripidae

    Directory of Open Access Journals (Sweden)

    María I. ZAMAR

    2011-01-01

    Full Text Available Se describen e ilustran los estados inmaduros de Heterothrips cacti Hood y se discuten las características biológicas y ecológicas de esta especie en las zonas semiáridas y de altura de Jujuy (Argentina. Los muestreos de frecuencia quincenal se realizaron en San Pedrito durante el período de floración de Opuntia sulphurea var. hildmannii en la temporada 2006-2007. La muestra consistió en cinco flores tomadas al azar de cada condición de evolución de las mismas. Para conocer las plantas hospedadoras y la distribución de H. cacti, se realizaron muestreos periódicos de la vegetación silvestre en la Prepuna y Puna de Jujuy. Los estudios biológicos se llevaron a cabo en el laboratorio, acondicionando flores de O. sulphurea con huevos de H. cacti en cajas de cría, para controlar la evolución del ciclo de vida. Heterothrips cacti es una especie antófila, oligófaga asociada a cactáceas, de amplia distribución en la Prepuna y Puna jujeñas. La biología de H. cacti está correlacionada con la de su planta hospedadora, O. sulphurea que presenta dos generaciones al año. Asimismo, el ciclo de vida está asociado con la evolución de la flor de la cactácea. El tiempo de desarrollo de los estados inmaduros de la primera y segunda generación fue de 45 ± 1.5 días y 287 ±3 días respectivamente. El estadio de desarrollo por el que la especie atraviesa el período entre floraciones es larva II quiescente, envuelta en un capullo de seda en el suelo. A 5 oC y 0 hs luz se inhibe el estado de quiescencia de H. cacti. Se registró la incidencia de Ceranisus sp. parasitoide larvi-pupal durante la segunda generación de H. cacti.

  13. Effects of an invasive grass on the demography of the Caribbean cactus Harrisia portoricensis: Implications for cacti conservation

    Science.gov (United States)

    Rojas-Sandoval, Julissa; Meléndez-Ackerman, Elvia

    2012-05-01

    The impact of exotic species around the world is among the primary threats to the conservation and management of rare and endangered species. In this work we asked whether or not the presence of the African grass Megathyrsus maximus on Mona Island was associated with negative impacts on the demography of the endangered Caribbean cactus Harrisia portoricensis. To address this question we performed field observations where we compared demographic data collected at un-manipulated areas invaded by Megathyrsus with un-manipulated areas non-invaded by this exotic grass. Additionally, demographic data were also collected in areas in which we removed the exotic grass biomass using two alternative treatments: complete and partial grass removal. Results demonstrated that the presence of Megathyrsus has negative effects on demographic parameters of Harrisia at various stages throughout its life cycle. In general, the survival, growth, and reproduction of Harrisia plants were depressed under the presence of Megathyrsus. Growth and survival of seedlings and juveniles of Harrisia were more impacted by the presence of Megathyrsus than adult performance and seedling recruitment only occurred in areas with grass absence. Our combined results suggest that modifications of the micro-environment by the presence of Megathyrsus may add an additional level of vulnerability to the persistence of Harrisia, and as such this factor must be considered when designing conservation strategies for this endangered species. This study highlights the need for a greater emphasis on understanding the interactions between invasive grass species and native cacti, and the importance of such information in designing conservation strategies for cacti species elsewhere.

  14. Use of columnar cacti in the Tehuacán Valley, Mexico: perspectives for sustainable management of non-timber forest products

    OpenAIRE

    Pérez-Negrón, Edgar; Dávila, Patricia; Casas, Alejandro

    2014-01-01

    Background TEK, ecological and economic aspects of columnar cacti were studied in the Tehuacán Valley, Mexico to design sustainable regimes of fruit harvest. We analysed the amounts of edible fruit, seeds and flowers produced per hectare of cardonal, jiotillal and tetechera forests, their economic value and actual extraction rates, hypothesizing that the economic benefits of these NTFP would potentially be comparable to maize agriculture, which involves forest removal. Methods Our study compr...

  15. Vulnerabilidad de los sistemas de polinización de cactáceas columnares de México Vulnerability of pollination systems of columnar cacti of Mexico

    Directory of Open Access Journals (Sweden)

    Alfonso Valiente-Banuet

    2002-03-01

    Full Text Available Se presenta un análisis geográfico sobre el grado de vulnerabilidad de los sistemas de polinización de cactáceas columnares de México que muestran un síndrome de polinización quiropterófila. Se partió del supuesto que sistemas especializados de polinización serían más vulnerables a la perturbación humana que los generalistas. Los resultados indican que las especies que se ubican en el límite norte de la distribución de las cactáceas columnares muestran patrones generalistas de polinización que las hace menos vulnerables a las perturbaciones que las que habitan el centro de México que presentan sistemas de interacción especializados. Este patrón contrastante podría estar relacionado con los movimientos migratorios de los murciélagos en el norte de la distribución de las cactáceas que pudo haber restringido la respuesta hacia la especialización, en tanto que poblaciones residentes de murciélagos en el centro de México podrían haber favorecido la especialización localAn analysis of the degree of vulnerability of the pollination systems of Mexican columnar cacti showing a chiropterophyllous pollination syndrome was conducted, assuming that specialized pollination interactions would be more vulnerable to human perturbations. The results indicate that the species inhabiting the northern distribution limit of the columnar cacti show generalized pollination systems whereas species inhabiting central Mexico showing specialized pollination interactions would be more vulnerable to perturbations. This contrasting geographic pattern might be related to the migratory movements of the nectar-feeding bats in the northern limit of distribution of the columnar cacti that restricted local specialization, whereas resident nectar-feeding bat populations in south-central Mexico probably favored local specialization

  16. Effects of natural and artificial selection on survival of columnar cacti seedlings: the role of adaptation to xeric and mesic environments.

    Science.gov (United States)

    Guillén, Susana; Terrazas, Teresa; Casas, Alejandro

    2015-05-01

    Escontria chiotilla, Polaskia chichipe, and Stenocereus pruinosus are species of Mexican columnar cacti that are economically important because of their edible fruits. These species are managed by gathering fruits from the wild, silvicultural management in agroforestry systems, and cultivation in home gardens. Previous studies reported that artificial selection favored individuals that produced larger fruits, which indirectly led to the production of larger seeds and seedlings, with possible effects on survival. We hypothesized that seedlings from managed populations would be larger but more susceptible to xeric conditions than those from wild populations. We evaluated the effects of artificial and natural selection on seedling survival of the three species in wild and managed populations, which were managed with low and high intensity, respectively. We tested seedling performance in gradients of shade (0, 40, and 80%) and humidity (low and high). A GLM of seedling survival showed significant differences among species, shade, and humidity treatments, with each species having environmental requirements associated with their particular adaptations. High humidity decreased seedling survival of all species, and high solar radiation decreased survival of S. pruinosus and P. chichipe. The effect of management type was significant only in S. pruinosus. Significant differences in the initial growth of seedlings among species were detected with ANOVA. In optimal conditions, the hypocotyl and the cotyledons decreased in size and the epicotyl grew, whereas under stress, these structures remained unchanged. The optimum conditions of shade and humidity varied among species and management types. The seedlings of S. pruinosus were the largest and the most susceptible, but in all species, seedlings from managed populations were more susceptible to environmental conditions. Thus, artificial selection influenced the susceptibility of these cacti to xeric environments. PMID

  17. Hitting Diamonds and Growing Cacti

    CERN Document Server

    Fiorini, Samuel; Pietropaoli, Ugo

    2009-01-01

    We consider the following problem: in a weighted graph, find a minimum cost set of vertices whose removal leaves a graph in which no two cycles share an edge. This NP-hard problem belongs to a general class of vertex deletion problems including the vertex cover problem and the feedback vertex set problem. We obtain a constant-factor approximation algorithm, based on the primal-dual method. Moreover, we show that the integrality gap of the natural LP relaxation of the problem is \\Theta(log n), where n denotes the number of vertices in the graph.

  18. Hitting Diamonds and Growing Cacti

    Science.gov (United States)

    Fiorini, Samuel; Joret, Gwenaël; Pietropaoli, Ugo

    We consider the following NP-hard problem: in a weighted graph, find a minimum cost set of vertices whose removal leaves a graph in which no two cycles share an edge. We obtain a constant-factor approximation algorithm, based on the primal-dual method. Moreover, we show that the integrality gap of the natural LP relaxation of the problem is Θ(logn), where n denotes the number of vertices in the graph.

  19. 有r个悬挂点仙人掌图的零阶广义Randic指数的界%On Bounds of Zero-order General Randic Index of Cacti with r Pendents

    Institute of Scientific and Technical Information of China (English)

    吕宁宁; 马艳丽

    2011-01-01

    设G为一简单连通图,则G的零阶广义Randic指数定义为Rα0(G)=∑ν∈V(G)dα(ν),其中d(v)为顶点ν的度数,α为非0和1的实数.图G称之为仙人掌图,如果G的每一块要么是一条边,要么是一个圈.本文研究有r个悬挂点仙人掌图的零阶广义Randic指数的界.L(n,r)、G(n,r)、H(n,r)、M(n,r)、N(n,r)分别表示一类图.当α〈0时,Rα0G)取得极大值当且仅当G∈M(n,r),Rα0取得极小值当且仅当G∈N(n,r);当0〈α〈1时,Rα0取得极大值当且仅当G∈N(n,r),Rα0取得极小值当且仅当G∈M(n,r);当α〉1时,Rα0取得极大值当且仅当G∈G(n,r),Rα0取得极小值当且仅当G∈H(n,r).%The zero-order general Randic index of a simple connected graph G is defined as R0α(G)=∑ν∈V(G)dα(ν),where d(ν) denotes the degree of ν,α is a given real number other than 0 and 1.A graph G is called a cactus if each block of G is either an edge or a cycle.In this paper,we present the sharp bounds of the zero-order general Randic index of cacti with r pendents.L(n,r),G(n,r),H(n,r),M(n,r)andN(n,r) denote some class of cacti respectvely.When α0,the maximal graph is in M(n,r) and the minimal graph is in N(n,r);when 0α1,the maximal graph is in N(n,r)and the minimal graph is in M(n,r);when α1,the maximal graph is in G(n,r)and the minimal graph is in H(n,r).

  20. Chromosome doubling in vine cacti hybrids.

    Science.gov (United States)

    Tel-Zur, N; Abbo, S; Bar-Zvi, D; Mizrahi, Y

    2003-01-01

    We performed reciprocal crosses between the tetraploid Selenicereus megalanthus and the diploid Hylocereus species, H. undatus and H. polyrhizus. S. megalanthus x H. undatus gave rise to viable hexaploids and 6x-aneuploid hybrids rather than to the expected triploids. No genuine hybrids were obtained in the reciprocal cross. The pollen diameter of the tetraploid S. megalanthus varied widely, indicating the occurrence of unreduced gametes, while that of H. undatus pollen was very uniform, indicating an extremely low frequency of unreduced gametes. This finding suggests that the hexaploids were formed by chromosome doubling after the formation of the hybrid triploid zygote rather than by fusion of unreduced gametes of the two species. PMID:12920104

  1. Fruit flesh betacyanin pigments in hylocereus cacti.

    Science.gov (United States)

    Wybraniec, Sławomir; Mizrahi, Yosef

    2002-10-01

    Determination of profiles and total contents of betacyanins in cactus fruits of Hylocereus species using chromatographic and spectrophotometric method is described. The investigated species were H. polyrhizus, H. purpusii, H. costaricensis, H. sp. 487 (all red-flesh species and hybrids made among them), and the white- or red-flesh species H. undatus. Hybrids included hybrid 1 (H. undatus white-flesh clone and H. sp. 487), hybrid 35 (H. sp. 487 and H. polyrhizus), and the reciprocal hybrid hybrid 95 (H. polyrhizus and H. sp. 487). Fruits of H. polyrhizus exhibited the highest relative concentration (expressed as percentage of the total HPLC peak area) of hylocerenin, a recently discovered pigment, and a high relative concentration of phyllocactin. Hylocerenin and isohylocerenin, present in fruits at relative concentrations of 11.7 and 5.8%, respectively, are probably responsible for the fluorescent color of the fruit pulp. H. costaricensis fruits have a much higher content of phyllocactin (63.9%), which is almost 4 times higher than the betanin content. These differences in pigment concentrations might explain the differences in red hues of the flesh of these fruits. PMID:12358484

  2. Utilização de cactáceas do gênero Pereskia na alimentação humana em um município de Minas Gerais Utilization of cacti of the genus Pereskia in the human diet in a municipality of Minas Gerais

    Directory of Open Access Journals (Sweden)

    Martha Elisa Ferreira de Almeida

    2012-04-01

    Full Text Available O objetivo deste trabalho foi avaliar a utilização de cactáceas do gênero Pereskia na alimentação humana. A pesquisa foi realizada nos 1.525 domicílios da cidade de São Gonçalo do Abaeté (MG. Nessa cidade, onde foi aplicado o questionário socioeconômico e quanto ao uso alimentar desta planta, comumente chamada de ora-pro-nóbis, somente 25 domicílios possuíam plantas do gênero Pereskia. Em 22 domicílios, havia a presença da Pereskia grandifolia, em três, havia a de Pereskia aculeata e, em um, havia os dois tipos. A presença de nutrientes na ora-pro-nobis foi citada por 83,33% dos entrevistados, sendo que 33,37% citaram um consumo mensal. A planta foi citada por 66,67% dos entrevistados como importante no tratamento da anemia ferropriva, por 16,67%, como agente terapêutico para o câncer, por 12,50%, para prevenção ou tratamento da osteoporose e, por 8,33%, para o tratamento da constipação intestinal. A classificação da ora-pro-nobis na categoria das hortaliças foi citada por 54,17% dos entrevistados. Concluiu-se que o resgate cultural do consumo desse tipo de planta poderá melhorar a condição nutricional e de renda das pessoas menos favorecidas economicamente, tanto no ambiente urbano quanto rural, de diferentes regiões do Brasil.The objective of this study was to evaluate the use of cacti of the genus Pereskia, for human consumption food. The study was conducted in 1.525 households in the city of São Gonçalo do Abaeté (MG. In this city where the socioeconomic questionnaire was applied regarding the dietary use of this plant, commonly referred to as ora-pro-nobis, only 25 of the households possessed plants of the genus Pereskia. In 22 households there was the presence of Pereskia grandifolia, in three households there was Pereskia aculeata, and one had both types. The presence of nutrients in the ora-pro-nobis was cited by 83.33% of respondents, where 33.37% cited monthly consumption. The plant was cited by 66

  3. Vine-cacti pitayas: the new crops of the world

    Directory of Open Access Journals (Sweden)

    Yosef Mizrahi

    2014-03-01

    Full Text Available Until 1994, only scarce research existed on these plants; however the worldwide interest in this novel fruit crop is evident, as numbers of pitaya-related publications have grown rapidly, especially during the past decade .There is a big confusion about both botanical and commercial names and there is a need to clear this point. Herein, we attempt to review existing knowledge on the taxonomy, breeding and other horticultural characteristics of this unique crop. This paper comments abou taxonomy,breeding,physiology and horticultura e chatera ristics,postsharvest and uses.

  4. Raman spectroscopy study of calcium oxalate extracted from cacti stems.

    Science.gov (United States)

    Frausto-Reyes, Claudio; Loza-Cornejo, Sofia; Terrazas, Teresa; Terrazas, Tania; Miranda-Beltrán, María de la Luz; Aparicio-Fernández, Xóchitl; López-Macías, Brenda M; Morales-Martínez, Sandra E; Ortiz-Morales, Martín

    2014-01-01

    To find markers that distinguish the different Cactaceae species, by using near infrared Raman spectroscopy and scanning electron microscopy, we studied the occurrence, in the stem, of solid deposits in five Cactaceae species (Coryphantha clavata, Ferocactus latispinus, Opuntia ficus-indica, O. robusta, and O. strepthacantha) collected from their natural habitats from a region of México. The deposits in the tissues usually occurred as spheroidal aggregates, druses, or prismatic crystals. From the Raman spectra, the crystals were identified either as calcium oxalate monohydrate (CaC2O4·H2O) or calcium oxalate dihydrate (CaC2O4·2H2O). Opuntia species (subfamily Opuntioideae) showed the presence of CaC2O4·H2O, and the deposition of CaC2O4·2H2O was present in C. clavata and F. latispinus (subfamily Cactoideae, Cacteae tribe). As a punctual technique, Raman spectroscopy seems to be a useful tool to identify crystal composition. In addition to allowing the analysis of crystal morphology, this spectroscopic technique can be used to identify Cactaceae species and their chemotaxonomy. PMID:25280368

  5. Labeling cacti with a condition at distance two

    Directory of Open Access Journals (Sweden)

    S. K. Vaidya

    2011-06-01

    Full Text Available  An L(2,1-labeling of a graph G is a function f  from the vertex set V(G to the set of all nonnegative integers such that | f (x- f (y| ≥ 2 if d(x, y = 1 and | f (x - f (y| ≥ 1 if d(x, y = 2. The L(2,1-labeling number λ(G of G is the smallest number k such that G has an L(2,1-labeling with max{f (v : v Î V(G} = k. In this paper we present a graph family which has λ-number Δ+1 or Δ+2.

  6. CACTI: Free, Open-Source Software for the Sequential Coding of Behavioral Interactions

    OpenAIRE

    Lisa H Glynn; Hallgren, Kevin A.; Houck, Jon M.; Moyers, Theresa B.

    2012-01-01

    The sequential analysis of client and clinician speech in psychotherapy sessions can help to identify and characterize potential mechanisms of treatment and behavior change. Previous studies required coding systems that were time-consuming, expensive, and error-prone. Existing software can be expensive and inflexible, and furthermore, no single package allows for pre-parsing, sequential coding, and assignment of global ratings. We developed a free, open-source, and adaptable program to meet t...

  7. New evidence for persistent or transient seed banks in three Sonoran Desert cacti

    Science.gov (United States)

    Bowers, Janice E.

    2005-01-01

    Seedlings of Ferocactus wislizeni and Mammillaria grahamii, 2 common cactus species in the northern Sonoran Desert, emerged under protective cages that had been left in place for 6 years after an initial sowing of numerous Carnegiea gigantea and F. wislizeni seeds. Because no seeds were sown in the interim, Mammillaria and Ferocactus seedlings must have emerged from persistent seed banks. Mammillaria seeds evidently survived in or on the soil as long as 6 years, forming a long-term persistent seed bank, and Ferocactus seeds apparently survived up to 3 years, forming a short-term persistent seed bank. No Carnegiea seedlings emerged, confirming that this species has a transient seed bank This is the first evidence for a between-year seed bank in M. grahamii and the first confirmation of a between-year seed bank in F. wislizeni.

  8. A new Sigelgaita Heinrich (Lepidoptera, Pyralidae, Phycitinae feeding on cacti in Brazil

    Directory of Open Access Journals (Sweden)

    Ricardo F. Monteiro

    2002-07-01

    Full Text Available Description and biological aspects of a new species of Sigelgaita Heinrich, 1939, the first known to occur east of the Andes, S. cerei Becker, are presented. S. cerei larvae were collected on "restinga" ecosystems feeding on Pilosocereus arrabidae (Lem. Byles & Rowl. (Parque Nacional da Restinga de Jurubatiba-Macaé and Área de Proteção Ambiental de Barra de Marica, Rio de Janeiro and rarely on Cereus obtusus Haw. (PNRJ. Life cycle and behavior of larvae are presented. Larvae are found singly on flower buds, on fruit or more frequently on stem of the plants. They build chambers in the cladodium where they complete their larval development, then droping to the ground in order to pupate. Trichogramma sp. was parasitizing 72% of eggs and a species of braconid was parasitizing half out of ten larvae collected from fruits of Cereus obtusus. S. cerei larvae develop a special role in the colonization and establishment of a diverse fauna associates with the hosts such as insects, spiders and yeasts. Ants, such as Camponotus crassus Mayr, 1862 and C. cingulatus Mayr, 1862 are among the insects which most frequently nest in the chambers abandoned by the larvae of this moth species.

  9. Branched ZnO wire structures for water collection inspired by cacti.

    Science.gov (United States)

    Heng, Xin; Xiang, Mingming; Lu, Zhihui; Luo, Cheng

    2014-06-11

    In this work, motivated by an approach used in a cactus to collect fog, we have developed an artificial water-collection structure. This structure includes a large ZnO wire and an array of small ZnO wires that are branched on the large wire. All these wires have conical shapes, whose diameters gradually increase from the tip to the root of a wire. Accordingly, a water drop that is condensed on the tip of each wire is driven to the root by a capillary force induced by this diameter gradient. The lengths of stem and branched wires in the synthesized structures are in the orders of 1 mm and 100 μm, respectively. These dimensions are, respectively, comparable to and larger than their counterparts in the case of a cactus. Two groups of tests were conducted at relative humidity of 100% to compare the amounts of water collected by artificial and cactus structures within specific time durations of 2 and 35 s, respectively. The amount of water collected by either type of structures was in the order of 0.01 μL. However, on average, what has been collected by the artificial structures was 1.4-5.0 times more than that harvested by the cactus ones. We further examined the mechanism that a cactus used to absorb a collected water drop into its stem. On the basis of the gained understanding, we developed a setup to successfully collect about 6 μL of water within 30 min. PMID:24498855

  10. Stem fasciation in cacti and succulent species--tissue anatomy, protein pattern and RAPD polymorphisms.

    Science.gov (United States)

    El-Banna, A N; El-Nady, M F; Dewir, Y H; El-Mahrouk, M E

    2013-09-01

    Fasciated and normal stem segments of Opuntia microdasys, Opuntia cylindrica, Huernia primulina and Euphorbia lactea were collected from the same plant and compared for their anatomy, water relations and genetic variations. Anatomical differences in terms of thickness of cuticle, vascular bundle, xylem and phloem were analyzed in both normal and fasciated stems. The mucilage cells were higher in the fasciated form of Opuntia microdasys than that in the normal form. Water status in terms of total water content (TWC), water deficit and relative water content (RWC) was influenced by fasciation. Genetic variations were tested in normal and fasciated stems using randomly amplified polymorphic DNA (RAPD) fingerprints and SDS-PAGE of soluble protein extracts. SDS-PAGE protein and RAPD analysis confirmed that normal and fasciated tissues were genetically different. Polymerase chain reaction (PCR) yielded different polymorphic banding patterns that were unique to each primer and distinguishable over all samples. The PCR results of normal and fasciated samples were significantly different in cases of primers P1, P2 and P3. These results indicate that occurrence of fasciation in Opuntia microdasys, Opuntia cylindrica, Huernia primulina and Euphorbia lactea is an epigenetic mutation of tissues. PMID:24013892

  11. Beyond aridification: multiple explanations for the elevated diversification of cacti in the New World Succulent Biome.

    Science.gov (United States)

    Hernández-Hernández, Tania; Brown, Joseph W; Schlumpberger, Boris O; Eguiarte, Luis E; Magallón, Susana

    2014-06-01

    Succulent plants are widely distributed, reaching their highest diversity in arid and semi-arid regions. Their origin and diversification is thought to be associated with a global expansion of aridity. We test this hypothesis by investigating the tempo and pattern of Cactaceae diversification. Our results contribute to the understanding of the evolution of New World Succulent Biomes. We use the most taxonomically complete dataset currently available for Cactaceae. We estimate divergence times and utilize Bayesian and maximum likelihood methods that account for nonrandom taxonomic sampling, possible extinction scenarios and phylogenetic uncertainty to analyze diversification rates, and evolution of growth form and pollination syndrome. Cactaceae originated shortly after the Eocene-Oligocene global drop in CO2 , and radiation of its richest genera coincided with the expansion of aridity in North America during the late Miocene. A significant correlation between growth form and pollination syndrome was found, as well as a clear state dependence between diversification rate, and pollination and growth-form evolution. This study suggests a complex picture underlying the diversification of Cactaceae. It not only responded to the availability of new niches resulting from aridification, but also to the correlated evolution of novel growth forms and reproductive strategies. PMID:24611540

  12. THE NUTRITIONAL COMPOSITION AND ACCEPTABILITY OF CACTI (Opuntia ficus indica-LEGUME MIXED SILAGE

    Directory of Open Access Journals (Sweden)

    J. GUSHA

    2013-03-01

    Full Text Available The potential of making silage using dry browse legume hay (Acacia angustissima, Leucaena leucocephala, Calliandra callothrysus and Macroptilium Atropurpureum mixed with fresh cactus (Opuntia ficus-indica for winter supplementation of veld grass was evaluated using the proximate, tannins and the pH analyses. Chemical analysis revealed that N values were significantly increased (P<0.05. The N levels were 3.72, 4.5, 4.05, and 2.5% DM for A. angustissima, L. leucocephala, C. callothrysus and M. atropurpureum respectively, which were higher when compared to silage made from cereals. The NDF and ADF values were slightly higher than those reported in literature for cereal silages. The DM level of cactus –browse silage was very good (41%DM considering that cactus normally have less than 10% DM. The silage pH was within the reported range, ranging from 3.97 to 4.11 on a pH meter. This was a good indicator of silage quality considering that low pH inhibit undesirable microbial activities. The tannins levels were lower in the silages but significantly different (P<0.05 between browse legume species. Ensiling lowered the tannin levels in the silage compared to the individual browse legume tannin levels. This study concluded that purely on compositional laboratory analysis, the legumes and cactus can be used to make silage which can be used by farmers during dry season.

  13. Cytogenetics of semi-fertile triploid and aneuploid intergeneric vine cacti hybrids.

    Science.gov (United States)

    Tel-Zur, N; Abbo, S; Mizrahi, Y

    2005-01-01

    Crosses between the diploid Hylocereus polyrhizus, as the female parent, and the tetraploid Selenicereus megalanthus, as the male parent, yielded triploid and aneuploid hybrids. The fruits of these hybrids combined the attractive appearance of Hylocereus fruits with the delicious taste of S. megalanthus fruits. The aim of this work was to assess the fertility and breeding potential of the triploid and aneuploid hybrids with a view to developing an improved vine cactus crop. Pollen mother cells at metaphase I revealed univalents, bivalents, trivalents, and occasionally quadrivalents. Chromosome distribution at anaphase I revealed different classes of chromosome segregation as well as lagging chromosomes. At metaphase II, parallel and tripolar spindles were observed. The occurrence of triads was frequent, whereas dyads were rarely observed. Pollen stainability varied among the clones studied ranging from 9.8% to 18.6%. The diameters of the stained pollen grains varied widely, probably as a result of the number of chromosomes. Despite the allotriploid origin of our hybrids, functional female and male gametes were produced in considerable proportions, most likely as a result of balanced chromosome segregation. The triploid and aneuploid clones studied yielded viable seeds whose number per fruit was strongly dependent on the pollen donor. PMID:15618308

  14. Lessons from Cacti: How to Survive the Prickles of Life during Tough Times

    Science.gov (United States)

    Bigger, Alan S.; Bigger, Linda B.

    2009-01-01

    The saguaro cactus looked a little like humans, in different shapes and sizes. How on earth do they survive in a climate that seems so inhospitable? It is possible to learn lessons for life from a cactus, if one can only get beyond the thorns, and that these lessons will assist one to survive during tough or prickly times. These plants survive…

  15. Copolymerization of Styrene and Methacrylates in the presence of Catalytic Chain Transfer Agents (Cacti's)

    International Nuclear Information System (INIS)

    The present paper focuses on the use of a Co (II) complex, [Co(afdo-H)] as a catalytic chain transfer agent (CCTA) for controlling molecular weight in copolymerization of styrene (STY) with butyl methacrylate (BMA) and methylmethacrylate (MMA). The catalyst is structurally similar to [co(dmg-H) (BF)] patented by Du Pont as a CCTA. Average catalytic chain transfer constant, C8 of [co(afdo-H) (BF)] for coplymerization of STY with BMA and MMA determined from Maya plot, was found to be in the range of 10-10.This value is lower than the value reported for the [Co(dmg-H)(BF)). In the case of STY-BMA or STY-MMA copolymerization, a considerable reduction in the viscosity average molecular weights (Mv) was observed in the copolymers. The average molecular weight of poly (MMA-BMA) was reduced by a factor of ten compared to the reduction in poly (STY-MMA) and poly (STY-BMA) for the same concentration of the CCTA. (author)

  16. Regenerative Capacity of Cacti Schlumbergera and Rhipsalidopsis in Relation to Endogenous Phytohormones, Cytokinin Oxidase/Dehydrogenase, and Peroxidase Activities

    Czech Academy of Sciences Publication Activity Database

    Sriskandarajah, S.; Prinsen, E.; Motyka, Václav; Dobrev, Petre; Serek, M.

    2006-01-01

    Roč. 25, č. 1 (2006), s. 79-88. ISSN 0721-7595 R&D Projects: GA ČR GA206/03/0313 Institutional research plan: CEZ:AV0Z50380511 Keywords : Cytokinin dehydrogenase * Cytokinin oxidase * Endogenous phytohormones * In vitro regeneration * Peroxidase * Rhipsalidopsis * Schlumbergera Subject RIV: EF - Botanics Impact factor: 2.107, year: 2006

  17. Targets of an invasive species: Oviposition preference and larval performance of Cactoblastis cactorum on 14 North American Opuntioid cacti

    Science.gov (United States)

    Cactoblastis cactorum (Lepidoptera: Pyralidae), the cactus moth, is a well-known biological control agent for cactus species of the genus Opuntia. The arrival of the moth in Florida and its subsequent spread through the southeastern United States poses a threat to opuntioid diversity in North Americ...

  18. Starmera pilosocereana sp. nov., a yeast isolated from necrotic tissue of cacti in a sandy coastal dune ecosystem.

    Science.gov (United States)

    Freitas, Larissa F D; Barbosa, Raquel; Sampaio, José Paulo; Lachance, Marc-André; Rosa, Carlos A

    2015-12-01

    Two strains of a novel cactophilic yeast species were isolated from the columnar cactus Pilosocereus arrabidae in a sand dune ecosystem in Rio de Janeiro, Brazil. Phylogenetic analysis of sequences of the large subunit rRNA gene D1/D2 domains showed that the strains represent a sister species to Starmera caribaea, from which it differs by 21 nt substitutions and two indels. The novel species is heterothallic and the asci are deliquescent with the formation of two to four hat-shaped ascospores. The name Starmera pilosocereana sp. nov. is proposed for the species. The type strain is UFMG-CM-Y316T ( = CBS 13266T) and the allotype is UFMG-CM-Y346a ( = CBS 13265). The Mycobank number is MB 810683. In addition, Candida stellimalicola belonging to the Starmera clade, is reassigned to Starmera as a new combination. PMID:26364192

  19. CO{sub 2} exchange environmental productivity indices, and productivity of agaves and cacti under current and elevated atmospheric CO{sub 2} concentrations. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Nobel, P.S.

    1994-12-31

    The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net C0{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.

  20. CO{sub 2} exchange, environmental productivity indices, and productivity of Agaves and Cacti under current and elevated atmospheric CO{sub 2} concentrations. Terminal report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net CO{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.

  1. 21 CFR 73.100 - Cochineal extract; carmine.

    Science.gov (United States)

    2010-04-01

    ... from an aqueous-alcoholic extract of cochineal (Dactylopius coccus costa (Coccus cacti L.)). The..., obtained by an aqueous extraction of cochineal (Dactylopius coccus costa (Coccus cacti L.)). (3)...

  2. Coevolution in the Galapagos: An Example for the Biology Classroom.

    Science.gov (United States)

    Biggs, Alton L.

    1990-01-01

    Several examples of coevolution which can be used in biology classes are presented. Discussed are evolutionary processes in general, giant cacti, and reptile and cacti association. The effects of human interference are briefly described. (CW)

  3. First report of a natural infection of Opuntia sp. by a 'Candidatus Phytoplasma asteris'-related phytoplasma in China

    Science.gov (United States)

    Cacti (Opuntia spp.) are perennial, evergreen, succulent plants native to arid areas of the Americas and West Indies. Because of their aesthetic appearance, many cacti have been cultivated and introduced into the international market as ornamental landscaping and house plants. Cacti are susceptibl...

  4. On Sharp Bounds of the Zero-order General Randic Index of Cacti with r(≥3) Cycles%有r(≥3)个圈仙人掌图的零阶广义Randic指数的界

    Institute of Scientific and Technical Information of China (English)

    吕宁宁; 刘家保

    2010-01-01

    设G为一简单连通图,则G的零阶广义Randic指数定义为R0α(G)=∑v∈V(G)dα(v),其中d(v)为顶点v的度数,α为非0和1的实数;图G称之为仙人掌图,如果G的每一块要么是一条边,要么是一个圈.此文主要研究有r(≥3)个圈仙人掌图的零阶广义Randic指数的界.

  5. Is geographical rarity frequent among the cacti of the Chihuahuan Desert? ¿Es la rareza geográfica frecuente entre las cactáceas del Desierto Chihuahuense?

    Directory of Open Access Journals (Sweden)

    Héctor M. Hernández

    2010-04-01

    Full Text Available With the aim of assessing the extent of geographical rarity of Mexican Cactaceae, we calculated the distribution size (area of occupancy of 142 species from the Chihuahuan Desert. In addition, using 2 variables (number of localities and range size, we preliminarily assessed their conservation status using the current IUCN Red List criteria. The results showed enormous variation in the areas of occupancy, although from the biogeographic and conservation perspective the most exceptional group comprises the extremely narrow endemics (42 species, whose range is restricted to areas smaller than 10 km2. Our results reinforce the reputation of this plant family as exceptionally rare geographically. We suggest that geographical rarity of Cactaceae in the Chihuahuan Desert is a natural phenomenon; however, we propose that the range of several species has been influenced by human activities. Regarding the conservation status of the species, 75 of them are categorized as Least concern. The remaining 67 species (47.2% fall in 1 of the 3 categories of threat (27 Vulnerable, 11 Endangered, and 29 Critically endangered. These figures confirm the critical conservation status of Mexican Cactaceae.Se calculó el tamaño de la distribución (área de ocupación de 142 especies de cactáceas del Desierto Chihuahuense, con el objeto de evaluar su grado de rareza geográfica. Además, mediante el uso de 2 variables (número de localidades y tamaño de distribución, se estimó de manera preliminar su estado de conservación usando los criterios actuales de la Lista Roja de la UICN. Los resultados mostraron gran variación en las áreas de ocupación. Sin embargo, desde una perspectiva biogeográfica y de la conservación, el grupo de especies más excepcional corresponde a las endémicas restringidas (42 spp., cuyas áreas de distribución son menores de 10 km². Los resultados fortalecen la reputación de las cactáceas de ser una familia de plantas excepcionalmente rara geográficamente. Se sugiere que la rareza geográfica en cactáceas es un fenómeno natural; sin embargo, se propone que la distribución de algunas de las especies ha sido influenciada por actividades humanas. En lo que respecta al estado de conservación de las especies, 75 pueden ser consideradas bajo la categoría de Preocupación menor, mientras que las restantes 67 (47.2% caen en alguna de las categorías de amenaza (Vulnerable = 27 spp., Amenazada = 11 spp., Críticamente amenazada = 29 spp.. Los resultados confirman el grave estado de conservación de las cactáceas mexicanas.

  6. Accumulation of silicon in cacti native to the United States: characterization of silica bodies and cyclic oligosiloxanes in Stenocereus thurberi, Opuntia littoralis, Opuntia ficus-indica, and Opuntia stricta.

    Science.gov (United States)

    Wright, Cynthia R; Waddell, Emanuel A; Setzer, William N

    2014-06-01

    Four different cactus species growing in the United States, Stenocereus thurberi growing in Organ Pipe Cactus National Monument, Arizona, Opuntia littoralis and Opuntia ficus-indica, growing on Santa Catalina Island, California, and Opuntia stricta, growing in northern Alabama, were examined for the presence of silica bodies (opaline phytoliths). Silica bodies were found in all four of these cactus species, parallelepiped-shaped crystals in S. thurberi, and starburst-shaped crystalline structures in the three Opuntia species. In addition, the essential oils of the four cactus species were obtained by hydrodistillation and analyzed by gas chromatography - mass spectrometry. To our surprise, S. thurberi, O. littoralis, and O. ficus-indica (but not O. stricta) essential oils contained cyclic oligosiloxanes. To our knowledge, cyclic oligosiloxanes have not been previously found as essential oil components. PMID:25115104

  7. Beware the BATUS Cactus--cactus dermatitis in exercising soldiers on the Albertan prairie.

    Science.gov (United States)

    Whitaker, J K H; Bailey, K G

    2012-09-01

    Species of the Opuntia or prickly pear genus of cacti are endemic to the British Army Training Unit Suffield (BATUS) training area in Alberta, Canada. They are known to provoke a dermatitis reaction in harvesters of the cacti fruit. It's spines are frequently an uncomfortable nuisance to unwary soldiers exercising in BATUS. We report two cases of particularly debilitating adverse skin reactions to the cacti spines that occurred during the 2010 Exercise Prairie Thunder season. PMID:23472572

  8. Identification and ecology of bacterial communities associated with necroses of three cactus species.

    OpenAIRE

    Foster, J. L.; Fogleman, J C

    1993-01-01

    To compare the bacterial communities residing in necrotic tissues of columnar cacti of the Sonoran Desert, isolates from 39 organ pipe, 19 saguaro, and 16 senita cacti were obtained. The isolates were clustered into 28 conspecific groups on the basis of their fatty acid profiles. The distributions of the individual bacterial isolates varied among cactus species. Seven of the 28 species groups were unique to a particular cactus species, whereas 8 species groups were found in all three cacti. T...

  9. Phylogeographic analysis of Harrisia cactus mealybug, Hypogeococcus pungens (Hemiptera: Pseudoccidae) populations: work in progress

    Science.gov (United States)

    Harrisia cactus mealybug (HCM), Hypogeococcus pungens (Hemiptera: Pseudoccidae) Granara de Willink (1981) is infesting and killing cacti in the southern coast of Puerto Rico, covering an area of about 1,400 km2. The 13 species of cacti occurring in Puerto Rico are threatened by this new pest; three...

  10. Using Interactive Technology to Enhance Student Comprehension and Retention.

    Science.gov (United States)

    Gordon, Stuart B.; Maples, John M., Jr.

    1995-01-01

    Describes the design of the Computer Assisted Classroom Training Improvement System (CACTIS), and discusses its use by the U.S. Military Academy (West Point, New York) to supplement the regular course curriculum. (AEF)

  11. Efecto de la densidad de semillas en la germinación de Isolatocereus dumortieri y Myrtillocactus geometrizans, cactáceas columnares endémicas de México Effect of seed density on germination of Isolatocereus dumortieri and Myrtillocactus geometrizans, endemic columnar cacti species from Mexico

    Directory of Open Access Journals (Sweden)

    Joel Flores

    2009-04-01

    Full Text Available Se evaluó el efecto de la densidad de semillas en la germinación de 2 cactáceas columnares: Isolatocereus dumortieri y Myrtillocactus geometrizans. Se utilizaron 5 tratamientos de densidad de semillas (1, 5, 10, 20 y 50 semillas. Isolatocereus dumortieri mostró menor porcentaje de germinación con el aumento de la densidad, mientras que la germinación de M. geometrizans no fue afectada por la densidad de semillas. Estos resultados sugieren que las plántulas de I. dumortieri podrían competir por recursos.The effect of seed density on the germination of 2 columnar cactus species (Isolatocereus dumortieri and Myrtillocactus geometrizans was evaluated using 5 seed density treatments (1, 5, 10, 20 and 50 seeds. Isolatocereus dumortieri had a lower germination percentage with increasing seed density; germination of M. geometrizans was not affected by seed density. These results suggest that I. dumortieri seedlings might compete for resources with siblings.

  12. A common Caatinga cactus, Pilosocereus gounellei, is an important ecotope of wild Triatoma brasiliensis populations in the Jaguaribe valley of northeastern Brazil.

    Science.gov (United States)

    Valença-Barbosa, Carolina; Lima, Marli M; Sarquis, Otília; Bezerra, Claudia M; Abad-Franch, Fernando

    2014-06-01

    Triatoma brasiliensis is the most important vector of Chagas disease in the Caatinga eco-region of northeastern Brazil. Wild T. brasiliensis populations have been reported only from rocky outcrops. However, this species frequently infests/re-infests houses in rock-free sedimentary lowlands. We therefore hypothesized that it should also occupy other natural ecotopes. We show that a common Caatinga cactus, Pilosocereus gounellei, locally known as xiquexique, often harbors T. brasiliensis breeding colonies apparently associated with rodents (n = 44 cacti, infestation rate = 47.7%, 157 bugs captured). Our findings suggest that infested cacti might be involved in house re-infestation by T. brasiliensis in the Caatinga region. PMID:24710611

  13. Fearful symmetry in aposematic plants

    OpenAIRE

    Lev-Yadun, Simcha

    2011-01-01

    Symmetry has been proposed to increase the efficiency of visual aposematic displays in animals, and I suggest that it may also be true for many aposematic spiny or poisonous plants. For instance, in the very spiny plant taxa cacti, Aloe sp., Agave sp. and Euphorbia sp., which have been proposed to be aposematic because of their colorful spine system, the shoots, and in cacti, the spiny fruits as well, are usually radially symmetric. Moreover, in the radial symmetric shoots of Agave and Aloe t...

  14. Amphimela raydahensis sp. nov. from the Kingdom of Saudi Arabia (Coleoptera: Chrysomelidae: Galerucinae: Alticini).

    Science.gov (United States)

    Torkey, Ashraf M El; Dhafer, Hathal M Al

    2015-01-01

    Amphimela raydahensis sp. nov. is described from Garf Raydah Nature Reserve (Abha, Asir Province), southwestern Kingdom of Saudi Arabia. This species was collected using black light traps at different elevations dominated by cacti and wild olive trees. This is the first confirmed species of Amphimela known from the Arabian Peninsula. PMID:26624320

  15. Biology, Distribution And Control Of The Cactus Moth, Cactoblastis Cactorum (Berg) (Lepidoptera: Pyralide)

    Science.gov (United States)

    The cactus moth, Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) became a textbook example of successful classical biological control after it was imported from Argentina into Australia in 1926 to control invasive Opuntia cacti. To date, the moth continues to play an active role in controlling...

  16. Biology and population dynamics of the cactus moth, Cactoblastis cactorum

    Science.gov (United States)

    The cactus moth, Cactoblastis cactorum, was a successful biological control agent against prickly pear cacti in Australia in the 1920’s. Since then, it was introduced to other countries including the Carribean islands. In 1989, the cactus moth was reported in Florida and has continued to spread nort...

  17. EXPANDING GEOGRAPHICAL RANGE OF CACTOBLASTIS CACTORUM (LEPIDOPTERA: PYRALIDAE) IN NORTH AMERICA

    Science.gov (United States)

    Observational surveys and virgin female-baited traps have identified the continued spread of the cactus moth, Cactoblastis cactorum, along the Atlantic and Gulf Coasts of the United States. The moth is infesting native and ornamental cacti north to Charleston, SC and west to St. George Island, FL. ...

  18. Desert Life, Experimental Edition Prepared for Testing in the Primary Grades.

    Science.gov (United States)

    Shelby, Betty; And Others

    This unit and teacher's guide were prepared for use with primary grade children. The activities include the construction of a desert terrarium, the study of cacti, and the use of animal sort cards. A special section is devoted to the way parents can help with the unit. A detailed list of needed materials is provided in the guide. This work was…

  19. Cactus Nurseries and Conservation in a Biosphere Reserve in Mexico

    Directory of Open Access Journals (Sweden)

    María T. Pulido

    2013-09-01

    Full Text Available Documenting how socio-ecosystem conservation knowledge and practice arise and are modified are issues of ethnobiological interest. In the Barranca de Metztitlán Biosphere Reserve (RBBM, plant nurseries, some of which were created as Environmental Management Units (UMAs, have been established to grow and conserve cacti. This paper describes these nurseries, their role in cactus conservation, and the benefits and limitations for the people managing them. The nurseries have helped decrease illegal traffic in cacti and have enabled ex situ conservation of 22 cacti species. Cactus management has changed from extraction to cultivation, as a result of the knowledge and actions of multiple actors. The main limitation is marketing, a recurring problem for non-timber forest products (NTFP. Greater coordination among stakeholders is recommended, such as involvement by non-governmental organizations to improve their probability of success, as well as learning from the experience of other cactus UMAs. Improving the market for cacti is an issue that needs an immediate solution; otherwise conservation efforts could relapse.

  20. The Sounds of Rain. Integrating Science in Your Classroom

    Science.gov (United States)

    Cowens, John

    2005-01-01

    Rainsticks are African and South American musical instruments that recreate the soothing sounds of rain. They were originally made of bamboo or dried cacti tubes. Inside the tubes are small river pebbles and cactus thorns. The longer the tube, the longer-lasting the "music." This article gives instructions for making both a large and small…

  1. Growing Indian Fig Opuntia on selenium-laden agriculture drainage sediment under field conditions

    Science.gov (United States)

    Growing alternative crops for saline and selenium (Se) impacted lands in arid regions, e.g., Western United States, depends upon the plant’s ability to tolerate the presence of high salts and boron (B). In this field study, we planted 2-month old cacti plants on 30 x 1m beds and evaluated the abilit...

  2. Rearing Cactoblastis cactorum (Lepidoptera: Pyralidae) on a factitious meridic diet at different temperatures and larval densities

    Science.gov (United States)

    Cactoblastis cactorum (Berg) is an invasive pest that represents an economic and ecological threat to native cacti in the U. S. and Mexico and that is currently the object of an eradication/control program in both countries. One tactic used to mitigate the threat of this species involves the SIT (St...

  3. Diet flight pattern and flight performance of Cactoblastis cactorum (Lepidoptera: Pyralidae) measured on a flight mill: The influence of age, gender, mating status and body size

    Science.gov (United States)

    Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) is an invasive herbivore that poses a serious risk to the rich diversity of Opuntia cacti in North America. Knowledge of the flight behavior of the cactus moth is crucial for a better understanding of natural dispersal, and for both monitoring an...

  4. Rearing Cactoblastis cactorum on artificial diet and Opuntia cladodes

    Science.gov (United States)

    The cactus moth, Cactoblastis cactorum Berg, is an invasive species that threatens economically and ecologically important native cacti in Mexico and the U.S. southwest. The insect presently occurs along the coastal U.S. from Charleston, SC, to Dauphin Island, south of Mobile, AL, and in the interi...

  5. Scale insects from the Netherlands Antilles

    NARCIS (Netherlands)

    Reyne, A.

    1964-01-01

    The following species have been reported from the Netherlands’ Antilles: Margarodes formicarum Guilding, collected in 1884 or 1885 by Prof. W. F. R. Suringar in Curaçao; specimens in the State Museum of Natural History at Leiden. Protortonia cacti (Linn.), collected in 1756 by Daniel Rolander in St.

  6. Young Maltese Children's Ideas about Plants

    Science.gov (United States)

    Gatt, Suzanne; Tunnicliffe, Sue Dale; Borg, Kurtsten; Lautier, Katya

    2007-01-01

    Fifty Maltese children, 25 in the second year of pre-school (4 years olds) and 25 in the first year of compulsory education (5 years old), were interviewed about their knowledge of plants. Analysis showed that they had a restricted understanding of the term, meaning something small, with a thin stalk, leaves and a flower. Trees, cacti and nettles…

  7. Field host range of Apanteles opuntiarum (Hymenoptera: Braconidae) in Argentina, a potential biocontrol agent of Cactoblastis cactorum (Lepidoptera: Pyralidae) in North America

    Science.gov (United States)

    Cactoblastis cactorum (Berg) (Lepidoptera, Pyralidae) was successfully used for biological control of Opuntia spp. (Cactaceae) in Australia and South Africa, where no native cacti occur. Since 1989, this South American moth has been invading the southeastern United States, threatening the unique ca...

  8. Antibacterial and antioxidant activities in extracts of fully grown cladodes of 8 cultivars of cactus pear.

    Science.gov (United States)

    Sánchez, E; Dávila-Aviña, J; Castillo, S L; Heredia, N; Vázquez-Alvarado, R; García, S

    2014-04-01

    The antimicrobial and antioxidant activities of some cultivars of the nopal cactus have not been determined. In this study, 8 cultivars of nopal cacti from Mexico were assayed for phenolic content, antioxidant activities, and antimicrobial activities against Campylobacter Jejuni, Vibrio cholera, and Clostridium Perfringens. Plant material was washed, dried, and macerated in methanol. Minimum bactericidal concentrations (MBCs) were determined using the broth microdilution method. Antioxidant activities were quantitatively determined using spectrophotometric methods. The MCBs of the nopal cacti ranged from 1.1 to 12.5 mg/mL for c. jejuni, 4.4 to 30 mg/mL for V. cholera, and 0.8 to 16 mg/mL for C. perfringens in the cultivars Cardon Blanco, Real de Catorce, and Jalpa, respectively. High quantities of total phenols and total flavonoids were found in the Jalpa cacti (3.80 mg of gallic acid equivalent GAE/g dry weight [DW] and 36.64 mg of quercetin equivalents [QE]/g DW, respectively). 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities (RSA) were correlated to bioactive compound contents. The Villanueva cacti had the highest %RSA at 42.31%, and the lowest activity was recorded in Copena V1 at 19.98%. In conclusion, we found that some of the 8 cactus pear cultivars studied may be used for their antioxidant compounds or antimicrobials to control or prevent the contamination of foods. PMID:24621296

  9. 76 FR 9978 - South American Cactus Moth; Territorial and Import Regulations

    Science.gov (United States)

    2011-02-23

    ... and economic damage. In a final rule published in the Federal Register on June 8, 2009 (74 FR 27071... effective on July 15, 2010 (75 FR 41073-41074, Docket No. APHIS-2010-0037), we added Louisiana to the list.... The importation of prickly pear pads, also called ``nopales,'' of Opuntia species cacti is...

  10. Are cactus growth forms related to germination responses to light? A test using Echinopsis species

    Science.gov (United States)

    Ortega-Baes, Pablo; Aparicio-González, Mónica; Galíndez, Guadalupe; del Fueyo, Patricia; Sühring, Silvia; Rojas-Aréchiga, Mariana

    2010-05-01

    In this study, we investigated the effect of light regimen (white light vs. darkness) on the germination of 12 species of the Echinopsis genus (tribe Trichocereeae, Cactaceae). This genus presents a variety of growth forms and relatively small and uniform seed size. These traits allowed us to test, within the same linage and removing seed mass effect, the hypothesis that the germination response to light (indifferent to light or positive photoblastic) is related to growth form. Our results reject this hypothesis since no seeds germinated in darkness, so all of the species can be classified as being positively photoblastic. The proportion of seed germination with white light was significantly different among cactus growth forms. Columnar cacti (arborescent, creeping and short) showed a greater proportion of seed germination than barrel and globose cacti. The germination rate differed among growth forms and species. At constant temperatures, creeping columnar cacti presented a significantly higher germination rate than the other growth forms. With alternating temperatures, columnar cacti showed higher germination rates than the other growth forms. The low proportion of seeds that germinated for some species indicates that they show seed dormancy. Our results suggest that germination responses to light in the cactus family could be related to seed mass and phylogenetic constraints.

  11. L(2, 1-Labelings of Some Families of Oriented Planar Graphs

    Directory of Open Access Journals (Sweden)

    Sen Sagnik

    2014-02-01

    Full Text Available In this paper we determine, or give lower and upper bounds on, the 2-dipath and oriented L(2, 1-span of the family of planar graphs, planar graphs with girth 5, 11, 16, partial k-trees, outerplanar graphs and cacti.

  12. Floral visitation by the Argentine ant reduces pollinator visitation and seed set in the coast barrel cactus, Ferocactus viridescens.

    Science.gov (United States)

    LeVan, Katherine E; Hung, Keng-Lou James; McCann, Kyle R; Ludka, John T; Holway, David A

    2014-01-01

    Mounting evidence indicates that trade-offs between plant defense and reproduction arise not only from resource allocation but also from interactions among mutualists. Indirect costs of plant defense by ants, for example, can outweigh benefits if ants deter pollinators. Plants can dissuade ants from occupying flowers, but such arrangements may break down when novel ant partners infiltrate mutualisms. Here, we examine how floral visitation by ants affects pollination services when the invasive Argentine ant (Linepithema humile) replaces a native ant species in a food-for-protection mutualism with the coast barrel cactus (Ferocactus viridescens), which, like certain other barrel cacti, produces extrafloral nectar. We compared the effects of floral visitation by the Argentine ant with those of the most prevalent native ant species (Crematogaster californica). Compared to C. californica, the Argentine ant was present in higher numbers in flowers. Cactus bees (Diadasia spp.), the key pollinators in this system, spent less time in flowers when cacti were occupied by the Argentine ant compared to when cacti were occupied by C. californica. Presumably as a consequence of decreased duration of floral visits by Diadasia, cacti occupied by L. humile set fewer seeds per fruit and produced fewer seeds overall compared to cacti occupied by C. californica. These data illustrate the importance of mutualist identity in cases where plants balance multiple mutualisms. Moreover, as habitats become increasingly infiltrated by introduced species, the loss of native mutualists and their replacement by non-native species may alter the shape of trade-offs between plant defense and reproduction. PMID:23892582

  13. Performance Evaluation for Clustering Algorithms in Object-Oriented Database Systems

    CERN Document Server

    Darmont, Jérôme; Gourgand, Michel

    1995-01-01

    It is widely acknowledged that good object clustering is critical to the performance of object-oriented databases. However, object clustering always involves some kind of overhead for the system. The aim of this paper is to propose a modelling methodology in order to evaluate the performances of different clustering policies. This methodology has been used to compare the performances of three clustering algorithms found in the literature (Cactis, CK and ORION) that we considered representative of the current research in the field of object clustering. The actual performance evaluation was performed using simulation. Simulation experiments we performed showed that the Cactis algorithm is better than the ORION algorithm and that the CK algorithm totally outperforms both other algorithms in terms of response time and clustering overhead.

  14. Sexual isolation and mating propensity among allopatric Drosophila mettleri populations.

    Science.gov (United States)

    Castrezana, Sergio J; Markow, Therese Ann

    2008-07-01

    Drosophila mettleri is found in deserts of North America breeding in soil soaked by the juices of necrotic cacti. Saguaro (Carnegiea gigantea) and cardón (Pachycereus pringlei) are the usual host cacti in Mexico and Arizona, while prickly pear (Opuntia spp.) is used by an isolated population on Santa Catalina Island off the southern California Coast. Populations of D. mettleri show significant local genetic differentiation, especially when geographical isolation is coupled with host shifts. We tested for evidence of sexual isolation among allopatric populations of D. mettleri using a variety of choice and no-choice tests. Populations exhibited significant differences in mating propensity, which translated into significant deviations from random mating. While in some cases these deviations were consistent with sexual isolation, in others, negative assortative mating was observed. No relationship between degree of genetic differentiation and the appearance of sexual isolation was detected. PMID:18561017

  15. Direct numerical simulation of flow past cactus--shaped cylinders

    Science.gov (United States)

    Babu, Pradeep; Mahesh, Krishnan

    2006-11-01

    The Saguaro cacti are tall, have short root systems and can withstand high wind velocities (Bulk 1984, Talley et al. 2002). Their trunks are essentially cylindrical with V--shaped longitudinal cavities. The size and number of cavities on the Saguaro cacti vary so that they have a near--constant fraction cavity depth (l/D ratio of about 0.07, Geller & Nobel 1984). Direct numerical simulations is used to assess the aerodynamic effect of the grooves on the cactus. DNS is performed for cactus shaped cylinders with l/d ratio's of 0.07 and 0.105, and smooth cylinders (l/d=0) at the same Reynolds number. Presence of the V--shaped cavities is found to decrease the drag on the cylindrical trunk as well as affect the fluctuating lift forces. The talk will quantify these differences, and discuss the physical mechanisms by which V--shaped cavities on the surface influence the flow.

  16. Water availability and the competitive effect of a columnar cactus on its nurse plant

    Science.gov (United States)

    Flores-Martínez, Arturo; Ezcurra, Exequiel; Sánchez-Colón, Salvador

    1998-02-01

    A field study was conducted in a semi-arid tropical ecosystem in Mexico to test whether competition for soil water is the causal mechanism underlying the negative effect of the columnar cactus Neobuxbaumia tetetzo on its nurse plant Mimosa luisana and to examine how this relationship varies over time. The effect of irrigation was evaluated by recording the production of leaves, modules (i.e. internodes with an axillary bud), inflorescences and fruits in shrubs growing either isolated or associated with juvenile or adult columnar cacti. 4 001 of water, in five doses of 801 each every 15 d, were added to the treatment plants; no water other than rainfall was added to control plants. Additionally, to evaluate how the effect of the columnar cacti on the shrubs may vary among years we made a comparison of the production of plant structures between 2 years of contrasting rainfall. The irrigation treatment increased the production of modules, inflorescences and fruits, but not of leaves. Shrub response to watering was also dependent on class of association: those associated with juvenile cacti showed a higher response to irrigation than any other treatment. Our results show that water addition increases the production of structures and partially reduces the negative effect of the cactus on nurse shrub, thus supporting the hypothesis of competition for water. The negative effect of the cacti on their nurse plants was present during both years of observations, but the intensity of the negative effect varies from relatively wet to dry years. The results are discussed in relation to how temporal changes in resource availability affect the results of competitive interactions and the importance of this mechanism in the structure and dynamics of this dryland community.

  17. Stem tilting in the inter-tropical cactus Echinocactus platyacanthus: an adaptive solution to the trade-off between radiation acquisition and temperature control.

    Science.gov (United States)

    Herce, M F; Martorell, C; Alonso-Fernandez, C; Boullosa, L F V V; Meave, J A

    2014-05-01

    While plants require radiation for photosynthesis, radiation in warm deserts can have detrimental effects from high temperatures. This dilemma may be solved through plant morphological attributes. In cold deserts, stem tilting keeps reproductive organs warm by increasing radiation interception at the cost of decreased annual light interception. Conversely, little is known about stem tilting in warm deserts. We hypothesised that stem tilting in Echinocactus platyacanthus prevents high temperatures near the apex, where reproduction occurs. The study was conducted in the warm, inter-tropical portion of the Chihuahuan Desert, Mexico. We found that cacti preferentially tilted towards the south, which reduced temperatures of reproductive organs during the hot season, but increased total annual near-apex PAR interception. Tilting also maximised reproduction, a likely consequence of temperature control but perhaps also of the difficulty in translocating photosynthates in cacti; therefore, annual energy acquisition near floral meristems may be largely allocated to reproduction. Unlike plants of higher latitudes, in inter-tropical deserts sunlight at noon comes either from the north or the south, depending on the season, and thus stem tilting may more strongly affect total annual radiation received in different portions of the stem. Inter-tropical cacti can synchronise reproduction with irradiance peaks if flowering occurs in a specific (north or south) portion of the stem; also, they effectively solve the conflict between maximising annual PAR interception and minimising temperature at the hottest time of day. Notably, the two inter-tropical cacti in which stem tilting has been studied successfully solve this conflict. PMID:23992581

  18. A cactus theorem for end cuts

    CERN Document Server

    Evangelidou, Anastasia

    2011-01-01

    Dinits-Karzanov-Lomonosov showed that it is possible to encode all minimal edge cuts of a graph by a tree-like structure called a cactus. We show here that minimal edge cuts separating ends of the graph rather than vertices can be `encoded' also by a cactus. We apply our methods to finite graphs as well and we show that several types of cuts can be encoded by cacti.

  19. Assessment of the invasive status of newly recorded cactus species in the central Tugela River basin

    Directory of Open Access Journals (Sweden)

    Michael D. Cheek

    2015-03-01

    Full Text Available Background: Current distribution information on cacti in the Tugela River basin in KwaZulu-Natal, South Africa, is scant. Accordingly, surveys in this region substantially improve our understanding of regional invasions by this succulent group. The identification of new or extended invasions requires (reassessments of their invasion status and consideration of possible management interventions.Objectives: To identify and collect cacti either not previously recorded or poorly known in the central Tugela River basin, and to assess their invasion status.Method: A 40 km section of tertiary road was travelled through the topocadastral square 2830 CC, from the R74 main road northward across the Bloukrans River towards the Tugela River. Herbarium specimens were collected to vouch for new instances of naturalisation of cacti, the colony sizes of which were estimated and invasion stages determined. An applicable weed risk assessment model was used to determine the threat status of one cactus species not previously evaluated for South Africa. Based on the South African Plant Invaders Atlas database records and field observations, management recommendations were suggested for six cacti species.Results: The first naturalised population of Opuntia microdasys in KwaZulu-Natal was detected, as was the first confirmed South African record of Echinopsis oxygona. Four populations of Peniocereus serpentinus were also found, ranging in size from several square metres to 0.4 ha. Echinopsis oxygona generated a score that falls into the reject category of the risk assessment model used.Conclusion: It is recommended that E. oxygona be added to the Species Under Surveillance for Possible Eradication or Containment Targeting list to investigate whether this species requires formal legal listing and the development of a specific eradication plan. Immediate action from local authorities is recommended for the manual removal of P. serpentinus and O. microdasys populations.

  20. The role of endogenous cytokinins and environmental factors in flowering in the vine cactus Hylocereus undatus

    OpenAIRE

    Khaimov-Armoza, A.; Novák, O.; Strnad, M; Mizrahi, Y.

    2012-01-01

    It has been found that application of exogenous cytokinins at a specific time induced flower induction in Hylocereus undatus (Haw.) Britt. & Rose. The aim of the present paper is to explore the role of cytokinins in flower induction in the cacti. Since endogenous cytokinins have never been analyzed in any cactus species, the initial step was to analyze endogenous cytokinins the year-round, and especially during the flowering period, when flower bud induction occurs. We found that the areoles ...

  1. Temperature in the seeds germination of pitaya genotypes

    OpenAIRE

    Alessandro Borini Lone; Ronan Carlos Colombo; Vanessa Favetta; Lúcia Sadayo Assari Takahashi; Ricardo Tadeu de Faria

    2014-01-01

    The optimum temperature for germination of cacti vary with the species. With this work, we aimed to evaluate the seeds germination of pitaya genotypes under different temperatures. The used genotypes were: Hylocereus undatus (PB), H. polyrhizus (PV), Selenicereus megalanthus (PA), H. undatus x H. costaricensis (PH1) and H. costaricensis x H. undatus (PH2). For each genotype we used four replicates of 50 seeds, in a completely randomized design. The sowing was carried out on blotter paper in b...

  2. Monophyly, divergence times, and evolution of host plant use inferred from a revised phylogeny of the Drosophila repleta species group.

    Science.gov (United States)

    Oliveira, Deodoro C S G; Almeida, Francisca C; O'Grady, Patrick M; Armella, Miguel A; DeSalle, Rob; Etges, William J

    2012-09-01

    We present a revised molecular phylogeny of the Drosophila repleta group including 62 repleta group taxa and nine outgroup species based on four mitochondrial and six nuclear DNA sequence fragments. With ca. 100 species endemic to the New World, the repleta species group represents one of the major species radiations in the genus Drosophila. Most repleta group species are associated with cacti in arid or semiarid regions. Contrary to previous results, maximum likelihood and Bayesian phylogenies of the 10-gene dataset strongly support the monophyly of the repleta group. Several previously described subdivisions in the group were also recovered, despite poorly resolved relationships between these clades. Divergence time estimates suggested that the repleta group split from its sister group about 21millionyears ago (Mya), although diversification of the crown group began ca. 16Mya. Character mapping of patterns of host plant use showed that flat leaf Opuntia use is common throughout the phylogeny and that shifts in host use from Opuntia to the more chemically complex columnar cacti occurred several times independently during the history of this group. Although some species retained the use of Opuntia after acquiring the use of columnar cacti, there were multiple, phylogenetically independent instances of columnar cactus specialization with loss of Opuntia as a host. Concordant with our proposed timing of host use shifts, these dates are consistent with the suggested times when the Opuntioideae originated in South America. We discuss the generally accepted South American origin of the repleta group. PMID:22634936

  3. Significance of saguaro cactus alkaloids in ecology ofDrosophila mettleri, a soil-breeding, cactophilic drosophilid.

    Science.gov (United States)

    Meyer, J M; Fogleman, J C

    1987-11-01

    Drosophila mettleri is a soil-breeding, cactophilic drosophilid which lives in the Sonoran Desert. Several chemical constituents of cacti in this region have been identified as having major roles in insect-host plant relationships involvingDrosophila. For example, isoquinoline alkaloids, which are present in senita cactus, have been shown to be toxic to seven of the nine species tested. The two tolerant species areD. pachea, the normal resident, andD. mettleri. Necroses of senita cacti are often used as feeding substrates byD. mettleri adults, but this species has never been reared from senita rots. Soil, which have been soaked by juice from saguaro and cardón rots, are the typical breeding substrates of this species. The tissues of both of these cacti also contain alkaloids, chemically related to those in senita, but at much lower concentrations. Alkaloid concentration in saguaro-soaked soil was found to be 1.4-27 times the average concentration in fresh tissue. Alkaloids were extracted from saguaro tissue and used in tests of larva-to-adult viability, developmental rate, and adult longevity. Elevated concentrations of saguaro alkaloids had no significant effect on the longevity ofD. mettleri, but significantly reduced the longevity ofD. nigrospiracula andD. mojavensis, two nonsoil breeding cactophilic species. Viability and developmental rates of all three species were affected, but the effect onD. nigrospiracula was comparatively greater. It is argued that the adaptations that allowD. mettleri to utilize the saguaro soil niche also convey tolerance to alkaloids present in senita tissue. The ability to utilize senita necroses as feeding substrates represents an ecological advantage to D. mettleri, in that the density of potential feeding sites is increased as compared to species which are more specific in their host-plant relationships. PMID:24301541

  4. Internal seed dispersal by parrots: an overview of a neglected mutualism

    Science.gov (United States)

    Bravo, Carolina; Pacifico, Erica C.; Chamorro, Daniel; Speziale, Karina L.; Lambertucci, Sergio A.; Hiraldo, Fernando; Tella, José L.

    2016-01-01

    Despite the fact that parrots (Psitacifformes) are generalist apex frugivores, they have largely been considered plant antagonists and thus neglected as seed dispersers of their food plants. Internal dispersal was investigated by searching for seeds in faeces opportunistically collected at communal roosts, foraging sites and nests of eleven parrot species in different habitats and biomes in the Neotropics. Multiple intact seeds of seven plant species of five families were found in a variable proportion of faeces from four parrot species. The mean number of seeds of each plant species per dropping ranged between one and about sixty, with a maximum of almost five hundred seeds from the cacti Pilosocereus pachycladus in a single dropping of Lear’s Macaw (Anodorhynchus leari). All seeds retrieved were small (<3 mm) and corresponded to herbs and relatively large, multiple-seeded fleshy berries and infrutescences from shrubs, trees and columnar cacti, often also dispersed by stomatochory. An overview of the potential constraints driving seed dispersal suggest that, despite the obvious size difference between seeds dispersed by endozoochory and stomatochory, there is no clear difference in fruit size depending on the dispersal mode. Regardless of the enhanced or limited germination capability after gut transit, a relatively large proportion of cacti seeds frequently found in the faeces of two parrot species were viable according to the tetrazolium test and germination experiments. The conservative results of our exploratory sampling and a literature review clearly indicate that the importance of parrots as endozoochorous dispersers has been largely under-appreciated due to the lack of research systematically searching for seeds in their faeces. We encourage the evaluation of seed dispersal and other mutualistic interactions mediated by parrots before their generalized population declines contribute to the collapse of key ecosystem processes. PMID:26925322

  5. Biodiversity of Myxomycetes from the Monte Desert of Argentina

    OpenAIRE

    Lado, C.; Wrigley de Basanta, D.; Estrada-Torres, A.

    2011-01-01

    A biodiversity survey for myxomycetes was carried out in the Monte Desert (Argentina) and surrounding areas in November 2006 and late February and March 2007. Specimens were collected in seven different provinces (Catamarca, Jujuy, La Rioja, Salta, San Juan, San Luis and Tucumán), between 23º and 33º S latitude, and a total of 105 localities were sampled. Cacti and succulent plants were the most common type of substrate investigated, but shrubs and herbs characteristic of this biome were also...

  6. Coherent dynamics on hierarchical systems

    Science.gov (United States)

    Blumen, Alexander; Bierbaum, Veronika; Mülken, Oliver

    2006-11-01

    We study the coherent transport modeled by continuous-time quantum walks, focussing on hierarchical structures. For these we use Husimi cacti, lattices dual to the dendrimers. We find that the transport depends strongly on the initial site of the excitation. For systems of sizes N⩽21, we find that processes which start at central sites are nearly recurrent. Furthermore, we compare the classical limiting probability distribution to the long time average of the quantum mechanical transition probability which shows characteristic patterns. We succeed in finding a good lower bound for the (space) average of the quantum mechanical probability to be still or again at the initial site.

  7. Noteworthy Record of Musonycteris harrisoni and Tlacuatzin canescens Pollinating a Columnar Cactus in West-Central Mexico

    Directory of Open Access Journals (Sweden)

    Luis I. Iniguez-Davalos

    2007-01-01

    Full Text Available We report Musonycteris harrisoni (Phyllostomidae and Tlacuatzin canescens (Didelphidae feeding of flowers during the blooming period (March and April 2004 of Stenocereus queretaroensis, an endemic cactus showing nocturnal anthesis and chiropterophilic syndrome. Visits were considered legitimate because both mammals made contact with the stigma and anthers, although their visits were highly infrequent compared with the principal pollinator Leptonycteris curasoae. These mammals are usually associated with pristine tropical forests, although our study site showed high habitat fragmentation and extensive agriculture. It is likely that both mammals feed regularly on nectar of cacti in pristine tropical forests thus acting actively as pollinators.

  8. Strong ƒ-Star Factors of Graphs

    Directory of Open Access Journals (Sweden)

    Yan Zheng

    2015-08-01

    Full Text Available Let G be a graph and f : V (G → {2, 3, . . .}. A spanning subgraph F is called strong f-star of G if each component of F is a star whose center x satisfies degF (x ≤ ƒ(x and F is an induced subgraph of G. In this paper, we prove that G has a strong f-star factor if and only if oddca(G − S ≤ ∑x∊S ƒ(x for all S ⊂ V (G, where oddca(G denotes the number of odd complete-cacti of G.

  9. Counting trees using symmetries

    CERN Document Server

    Bernardi, Olivier

    2012-01-01

    We present a new approach for counting trees, and we apply it to count multitype Cayley trees and to prove the multivariate Lagrange inversion formula. The gist of our approach is to exploit the symmetries of refined enumerative formulas: proving these symmetries is easy, and once the symmetries are proved the formulas follow effortlessly. Somewhat surprisingly, our formula for the generating function of multitype Cayley trees appears to be new, and implies certain recent results by Bousquet-M\\'elou and Chapuy. We also adapt our approach to recover known enumerative formulas for cacti counted according to their degree distribution.

  10. Asymptotic study of subcritical graph classes

    CERN Document Server

    Drmota, Michael; Kang, Mihyun; Kraus, Veronika; Rué, Juanjo

    2010-01-01

    We present a unified general method for the asymptotic study of graphs from the so-called "subcritical"$ $ graph classes, which include the classes of cacti graphs, outerplanar graphs, and series-parallel graphs. This general method works both in the labelled and unlabelled framework. The main results concern the asymptotic enumeration and the limit laws of properties of random graphs chosen from subcritical classes. We show that the number $g_n/n!$ (resp. $g_n$) of labelled (resp. unlabelled) graphs on $n$ vertices from a subcritical graph class ${\\cG}=\\cup_n {\\cG_n}$ satisfies asymptotically the universal behaviour

  11. Characterization of a mineral coating of the plant Dyerophytum indicum.

    Science.gov (United States)

    Chernyshev, Anatoly; Melghit, Khaled

    2015-01-01

    The mineral coating of Dyerophytum indicum Kuntze (Plumbaginaceae) was analyzed by isotope ratio mass spectrometry, X-ray diffraction, thermogravimetric and differential thermal analysis, and scanning electron microscopy/energy-dispersive X-ray spectroscopy methods. Its composition was found to be similar to those of the carbonate mixtures isolated from rotting cacti and speleothems. The coating consisted of three major phases (monohydrocalcite, nesquehonite, and calcite), a minor phase of hydromagnesite, and traces of silica and sylvite. This is the first time that the occurrence of monohydrocalcite, nesquehonite, and hydromagnesite in a living higher plant has been reported. A possible mechanism of the formation of the coating is also discussed. PMID:26020556

  12. Polymer chain in a random array of topological obstacles: Classification and statistics of complex loops

    Science.gov (United States)

    Rostiashvili, V. G.; Nechaev, S. K.; Vilgis, T. A.

    1993-11-01

    An arbitrary complex polymer loop embedded in three-dimensional space and topologically entangled with a quenched array of randomly dstributed parallel rods is considered. It is shown that an ensemble of the complex loops, prepared in different possible ways, is equivalent to the ensemble of cactuslike graphs where the leaves of these cacti are simple loops. The free energy of the cactuslike graphs is calculated in the mean-field approximation. The critical condition for the collapse transition is obtained. The collapsed state of the complex loop with the density distributed over different leaves is shown to be preferable.

  13. Candida coquimbonensis sp. nov., a link between Australian and Nearctic/Neotropical Phaffomyces.

    Science.gov (United States)

    Cardinali, Gianluigi; Antonielli, Livio; Corte, Laura; Roscini, Luca; Ganter, Philip F

    2012-12-01

    A novel species of ascomycetous yeast, Candida coquimbonensis sp. nov., from the necrotic tissue of cacti in Chile and Australia is described. C. coquimbonensis sp. nov. is closely related and phenotypically similar to Phaffomyces opuntiae. There is no overlap in the geographical distribution between C. coquimbonensis and any species in the Phaffomyces clade. However, this is the first member of the clade to be collected in both native (Chile) and non-native (Australia) cactus habitats. The type strain of C. coquimbonensis sp. nov. is TSU 00-206.4B(T) ( = CBS 12348(T) = USCFST 12-103(T)). PMID:22729024

  14. Wood Chemical Composition in Species of Cactaceae: The Relationship between Lignification and Stem Morphology

    OpenAIRE

    Jorge Reyes-Rivera; Gonzalo Canché-Escamilla; Marcos Soto-Hernández; Teresa Terrazas

    2015-01-01

    In Cactaceae, wood anatomy is related to stem morphology in terms of the conferred support. In species of cacti with dimorphic wood, a unique process occurs in which the cambium stops producing wide-band tracheids (WBTs) and produces fibers; this is associated with the aging of individuals and increases in size. Stem support and lignification have only been studied in fibrous tree-like species, and studies in species with WBTs or dimorphic wood are lacking. In this study, we approach this pro...

  15. Theoretical Exploration of Barrel-Shaped Drops on Cactus Spines.

    Science.gov (United States)

    Luo, Cheng

    2015-11-01

    To survive an arid environment, desert cacti are capable of harvesting water from fog by transporting condensed water drops using their spines. Cactus spines have a conical shape. In this work, on the basis of the difference of liquid pressure, a new theoretical model has been developed for a barrel-shaped liquid drop on a conical wire. This model is further simplified to interpret the effects of contact angles, conical angle, surface microgrooves, and gravity on the drop movement along a cactus spine. PMID:26473466

  16. Variability of Seed Traits in Interspecific and Intergeneric Combinations between Different Genotypes of Cactaceae

    Directory of Open Access Journals (Sweden)

    Lucica MIHALTE

    2010-12-01

    Full Text Available Based on aesthetic consideration of cacti plants and germination capacity of the pollen grains (more than 30%, 19 genotypes of cacti (including Aylostera narvaecensis, A. buiningiana, Rebutia kupperiana var. spiniflorum, R. donaldiana have been used in cyclic cross-pollination pattern. Fruits and seeds obtained from 24 interspecific and intergeneric combinations were analyzed by studying their main traits. The highest weight was registered for fruit belonging to R. pseudodeminuta var. schumaniana x R. senilis (23.3 mg and A. buiningiana x A. vallegardensis (20.4 mg. Coefficient of variability for fruit weight had large amplitude, between 12.3% (A. spinosissima x A. albiflora and 98.4% (A. favistyla x A. archibuinigiana. The fruits belonging to A. muscula x A. vallegardensis were registered with the highest value of number of seeds/fruit (93.2. In the cross between genera, the greatest value of fruits weights mean was registered on R. senilis x A. archibuinigiana (29.2 mg and R. cajasensis x A. muscula (23.1 mg. Peculiarities of the fruits and seeds resulted from intergeneric combinations presented closer connections than interspecific ones. The phenotypic traits of fruits and seeds did not influence the seeds germination, but germination was clearly influenced by compatibility between genitors.

  17. Premating isolation is determined by larval rearing substrates in cactophilic Drosophila mojavensis. IX. Host plant and population specific epicuticular hydrocarbon expression influences mate choice and sexual selection.

    Science.gov (United States)

    Havens, J A; Etges, W J

    2013-03-01

    Sexual signals in cactophilic Drosophila mojavensis include cuticular hydrocarbons (CHCs), contact pheromones that mediate female discrimination of males during courtship. CHCs, along with male courtship songs, cause premating isolation between diverged populations, and are influenced by genotype × environment interactions caused by different host cacti. CHC profiles of mated and unmated adult flies from a Baja California and a mainland Mexico population of D. mojavensis reared on two host cacti were assayed to test the hypothesis that male CHCs mediate within-population female discrimination of males. In multiple choice courtship trials, mated and unmated males differed in CHC profiles, indicating that females prefer males with particular blends of CHCs. Mated and unmated females significantly differed in CHC profiles as well. Adults in the choice trials had CHC profiles that were significantly different from those in pair-mated adults from no-choice trials revealing an influence of sexual selection. Females preferred different male CHC blends in each population, but the influence of host cactus on CHC variation was significant only in the mainland population indicating population-specific plasticity in CHCs. Different groups of CHCs mediated female choice-based sexual selection in each population suggesting that geographical and ecological divergence has the potential to promote divergence in mate communication systems. PMID:23286346

  18. Novel seed coat lignins in the Cactaceae: structure, distribution and implications for the evolution of lignin diversity.

    Science.gov (United States)

    Chen, Fang; Tobimatsu, Yuki; Jackson, Lisa; Nakashima, Jin; Ralph, John; Dixon, Richard A

    2013-01-01

    We have recently described a hitherto unsuspected catechyl lignin polymer (C-lignin) in the seed coats of Vanilla orchid and in cacti of one genus, Melocactus (Chen et al., Proc. Natl. Acad. Sci. USA. 2012, 109, 1772-1777.). We have now determined the lignin types in the seed coats of 130 different cactus species. Lignin in the vegetative tissues of cacti is of the normal guaiacyl/syringyl (G/S) type, but members of most genera within the subfamily Cactoidae possess seed coat lignin of the novel C-type only, which we show is a homopolymer formed by endwise β-O-4-coupling of caffeyl alcohol monomers onto the growing polymer resulting in benzodioxane units. However, the species examined within the genera Coryphantha, Cumarinia, Escobaria and Mammillaria (Cactoideae) mostly had normal G/S lignin in their seeds, as did all six species in the subfamily Opuntioidae that were examined. Seed coat lignin composition is still evolving in the Cactaceae, as seeds of one Mammillaria species (M. lasiacantha) possess only C-lignin, three Escobaria species (E. dasyacantha, E. lloydii and E. zilziana) contain an unusual lignin composed of 5-hydroxyguaiacyl units, the first report of such a polymer that occurs naturally in plants, and seeds of some species contain no lignin at all. We discuss the implications of these findings for the mechanisms that underlie the biosynthesis of these newly discovered lignin types. PMID:22957702

  19. Two new species of Anagyrus (Hymenoptera: Encyrtidae) from Argentina, parasitoids of Hypogeococcus spp. (Hemiptera: Pseudococcidae), with taxonomic notes on some congeneric taxa.

    Science.gov (United States)

    Triapitsyn, Serguei V; Logarzo, Guillermo A; Aguirre, María B; Aquino, Daniel A

    2014-01-01

    Two new species of Anagyrus Howard (Hymenoptera: Encyrtidae) are described from Argentina, A. cachamai Triapitsyn, Logarzo & Aguirre sp. n. (Catamarca, Córdoba, Salta and Tucumán Provinces) and A. quilmes Triapitsyn, Logarzo & Aguirre sp. n. (Catamarca, Salta and Tucumán). Both new species are parasitoids of Hypogeococcus spp. (Hemiptera: Pseudococcidae). Anagyrus cachamai is a parasitoid of H. pungens Granara de Willink on Alternanthera paronychioides, A. pungens and Gomphrena sp. (Amaranthaceae), and also of a Hypogeococcus sp. on Cleistocactus baumannii and Hypogeococcus sp. on C. smaragdiflorus (Cactaceae). Anagyrus quilmes is a parasitoid of H. pungens on A. paronychioides, A. pungens and Gomphrena sp. Other biological traits of the new species are also reported. These parasitoids may be of importance as potential candidate biological control agents against a Hypogeococcus sp., commonly called the Harrisia cactus mealybug and identified as H. pungens, but possibly not belonging to that species. This mealybug threatens the native cacti in some Caribbean islands and Florida, USA, and is devastating the native columnar cacti in Puerto Rico. Illustrations and taxonomic notes on the type specimens of some other, little known described species of Anagyrus from Argentina and Chile are provided, and a key to females of the 14 species of Anagyrus known from Argentina is given. Anagyrus nigriceps (De Santis) syn. n. is synonymized under A. bellator (De Santis). Lectotypes are designated for Paranusia bifasciata Brèthes, Philoponectroma pectinatum Brèthes, and Protanagyrus aciculatus Blanchard.  PMID:25283404

  20. A bijection between planar constellations and some colored Lagrangian trees

    Directory of Open Access Journals (Sweden)

    Cedric Chauve

    2003-06-01

    Full Text Available Constellations are colored planar maps that generalize different families of maps (planar maps, bipartite planar maps, bi-Eulerian planar maps, planar cacti, ... and are strongly related to factorizations of permutations. They were recently studied by Bousquet-Mélou and Schaeffer who describe a correspondence between these maps and a family of trees, called Eulerian trees. In this paper, we derive from their result a relationship between planar constellations and another family of trees, called stellar trees. This correspondence generalizes a well known result for planar cacti, and shows that planar constellations are colored Lagrangian objects (that is objects that can be enumerated by the Good-Lagrange formula. We then deduce from this result a new formula for the number of planar constellations having a given face distribution, different from the formula one can derive from the results of Bousquet-Mélou and Schaeffer, along with systems of functional equations for the generating functions of bipartite and bi-Eulerian planar maps enumerated according to the partition of faces and vertices.

  1. Anatomical variation in Cactaceae and relatives: Trait lability and evolutionary innovation.

    Science.gov (United States)

    Ogburn, R Matthew; Edwards, Erika J

    2009-02-01

    The cacti have undergone extensive specialization in their evolutionary history, providing an excellent system in which to address large-scale questions of morphological and physiological adaptation. Recent molecular phylogenetic studies suggest that (1) Pereskia, the leafy genus long interpreted as the sister group of all other cacti, is likely paraphyletic, and (2) Cactaceae are nested within a paraphyletic Portulacaceae as a member of the "ACPT" clade (Anacampseroteae, Cactaceae, Portulaca, and Talinum). We collected new data on the vegetative anatomy of the ACPT clade and relatives to evaluate whether patterns in the distributions of traits may provide insight into early events in the evolutionary transition to the cactus life form. Many traits had high levels of homoplasy and were mostly equivocal with regard to infraclade relationships of ACPT, although several characters do lend further support to a paraphyletic Pereskia. These include a thick stem cuticle, prominent stem mucilage cells, and hypodermal calcium oxalate druses, all of which are likely to be important traits for stem water storage and photosynthesis. We hypothesize that high lability of many putative "precursor" traits may have been critical in generating the organismal context necessary for the evolution of an efficient and integrated photosynthetic stem. PMID:21628195

  2. A colourful approach to string topology

    DEFF Research Database (Denmark)

    Bargheer, Tarje

    For M a compact, orientable manifold and N „ Rn􀀀1 a submanifold, we construct the cleavage operad that acts on MN through correspondences, analogous to the Cacti Operad acting on MS1 , formulating String Topology. For the unit sphere, N : Sn „ Rn􀀀1 we compute the cleavage operad...... MSn, and provide apparent links between Knot Theory and String Topology.......For M a compact, orientable manifold and N „ Rn􀀀1 a submanifold, we construct the cleavage operad that acts on MN through correspondences, analogous to the Cacti Operad acting on MS1 , formulating String Topology. For the unit sphere, N : Sn „ Rn􀀀1 we compute the cleavage operad......Mq. This action is obtained through an extension of the Cleavage Operad. Homotopically the extension is a simplication, and it adjoins a unit to the action on MSn. We nally give advantages of our geometric stance on generalizing String Topology even when N S1:We improve on equivariance of group actions on...

  3. Resolving a Prickly Situation: Involving Stakeholders in Invasive Cactus Management in South Africa

    Science.gov (United States)

    Novoa, Ana; Kaplan, Haylee; Wilson, John R. U.; Richardson, David M.

    2016-05-01

    The regulation and management of alien species can be contentious, particularly when the stakeholders who benefit from alien species are different from those who suffer the costs. We propose a consultative process involving relevant stakeholders in invasive species management decisions. The process involves (1) the identification of relevant stakeholders, (2) assessing their perceptions, (3) enhancing interaction between stakeholders, (4) assessing changes in stakeholders' perceptions following interactions with other stakeholders, and (5) developing management recommendations in collaboration with stakeholders. We demonstrate the application of the process using the family Cactaceae (`cacti') in South Africa. Many species of cacti have been introduced to the country over the past two centuries, mostly for horticulture, food and fodder, and hundreds of other species have been introduced in the past few decades (or are likely to be introduced soon) for horticulture. Using the proposed process enabled the negotiation and participation of all stakeholders in decision making and helped minimize contentious situations by clarifying stakeholder's beliefs and exploring consensus solutions. Consequently, management objectives were broadly supported by all stakeholders. These results will be included in a national cactus management strategy for South Africa.

  4. Studies on the Biology of Hypogeococcus pungens (sensu stricto) (Hemiptera: Pseudococcidae) in Argentina to Aid the Identification of the Mealybug Pest of Cactaceae in Puerto Rico

    Science.gov (United States)

    Aguirre, M. B.; Diaz-Soltero, H.; Claps, L. E.; Saracho Bottero, A.; Triapitsyn, S.; Hasson, E.; Logarzo, G. A.

    2016-01-01

    Hypogeococcus pungens Granara de Willink, sensu stricto, is a serious pest of cacti in Puerto Rico threating many Caribbean islands. A classical biological control program for H. pungens was initiated for Puerto Rico in 2010 with a survey for natural enemies of H. pungens in its native range of Argentina. Biological differences were observed between populations of H. pungens sampled on Amaranthaceae and Cactaceae. Molecular studies suggested that H. pungens populations from different host plant families are likely a complex of species. Our objective was to study the biology of H. pungens sensu stricto on specimens collected in the same locality and host plant as the holotype [Tucumán Province, Argentina; Alternanthera pungens Kunth (Amaranthaceae)]. We were interested in the reproductive biology of females, longevity and survival of adults, the effect of temperature on the development, and nymph performance (survival and development) on five Cactaceae species. We found that H. pungens s.s. showed marked biological differences from the populations collected on Cactaceae and exported to Australia for the biological control of the cactus Harrisia spp. The main differences were the presence of deuterotoky parthenogenesis and the fact that H. pungens did not attack Cactaceae in the laboratory. Our results provide biological evidence that H. pungens is a species complex. We propose that the population introduced to Australia is neither Hypogeococcus festerianus Lizer y Trelles nor H. pungens, but an undescribed species with three circuli, and that the Hypogeococcus pest of cacti in Puerto Rico is not H. pungens. PMID:27324585

  5. Past climate changes and ecophysiological responses recorded in the isotope ratios of saguaro cactus spines.

    Science.gov (United States)

    English, Nathan B; Dettman, David L; Sandquist, Darren R; Williams, David G

    2007-11-01

    The stable isotope composition of spines produced serially from the apex of columnar cacti has the potential to be used as a record of changes in climate and physiology. To investigate this potential, we measured the delta(18)O, delta(13)C and F(14)C values of spines from a long-lived columnar cactus, saguaro (Carnegiea gigantea). To determine plant age, we collected spines at 11 different heights along one rib from the stem apex (3.77 m height) to the base of a naturally occurring saguaro. Fractions of modern carbon (F(14)C) ranged from 0.9679 to 1.5537, which is consistent with ages between 1950 and 2004. We observed a very strong positive correlation (r = 0.997) between the F(14)C age of spines and the age of spines determined from direct and repeated height measurements taken on this individual over the past 37 years. A series of 96 spines collected from this individual had delta(18)O values ranging from 38 per thousand to 50 per thousand [Vienna standard mean ocean water (VSMOW)] and delta(13)C values from -11.5 per thousand to -8.5 per thousand [Vienna Peedee belemnite (VPDB)]. The delta(18)O and delta(13)C values of spines were positively correlated (r = 0.45, P < 0.0001) and showed near-annual oscillations over the approximately 15-year record. This pattern suggests that seasonal periods of reduced evaporative demand or greater precipitation input may correspond to increased daytime CO(2) uptake. The lowest delta(18)O and delta(13)C values of spines observed occurred during the 1983 and 1993 El Niño years, suggesting that the stable isotope composition recorded in spine tissue may serve as a proxy for these climate events. We compared empirical models and data from potted experimental cacti to validate these observations and test our hypotheses. The isotopic records presented here are the first ever reported from a chronosequence of cactus spines and demonstrate that tissues of columnar cacti, and potentially other long-lived succulents, may contain a

  6. The complex of looped diagrams and natural operations on Hochschild homology

    DEFF Research Database (Denmark)

    Klamt, Angela

    In this thesis natural operations on the (higher) Hochschild complex of a given family of algebras are investigated. We give a description of all formal operations (in the sense of Wahl) for the class of commutative algebras using Loday's lambda operation, Connes' boundary operator and shue...... products. Furthermore, we introduce a dg-category of looped diagrams and show how to generate operations on the Hochschild complex of commutative Frobenius algebras out of these. This way we recover all operations known for symmetric Frobenius algebras (constructed via Sullivan diagrams), all the formal...... operations for commutative algebras (as computed in the rst part of the thesis) and a shifted BV structure which has been investigated by Abbaspour earlier. We prove that this BV structure comes from a suspended Cacti operad sitting inside the complex of looped diagrams. Last, we eneralize the setup of...

  7. A Novel Method of Genomic DNA Extraction for Cactaceae

    Directory of Open Access Journals (Sweden)

    Shannon D. Fehlberg

    2013-03-01

    Full Text Available Premise of the study: Genetic studies of Cactaceae can at times be impeded by difficult sampling logistics and/or high mucilage content in tissues. Simplifying sampling and DNA isolation through the use of cactus spines has not previously been investigated. Methods and Results: Several protocols for extracting DNA from spines were tested and modified to maximize yield, amplification, and sequencing. Sampling of and extraction from spines resulted in a simplified protocol overall and complete avoidance of mucilage as compared to typical tissue extractions. Sequences from one nuclear and three plastid regions were obtained across eight genera and 20 species of cacti using DNA extracted from spines. Conclusions: Genomic DNA useful for amplification and sequencing can be obtained from cactus spines. The protocols described here are valuable for any cactus species, but are particularly useful for investigators interested in sampling living collections, extensive field sampling, and/or conservation genetic studies.

  8. Australia lacks stem succulents but is it depauperate in plants with crassulacean acid metabolism (CAM)?

    Science.gov (United States)

    Holtum, Joseph Am; Hancock, Lillian P; Edwards, Erika J; Crisp, Michael D; Crayn, Darren M; Sage, Rowan; Winter, Klaus

    2016-06-01

    In the flora of Australia, the driest vegetated continent, crassulacean acid metabolism (CAM), the most water-use efficient form of photosynthesis, is documented in only 0.6% of native species. Most are epiphytes and only seven terrestrial. However, much of Australia is unsurveyed, and carbon isotope signature, commonly used to assess photosynthetic pathway diversity, does not distinguish between plants with low-levels of CAM and C3 plants. We provide the first census of CAM for the Australian flora and suggest that the real frequency of CAM in the flora is double that currently known, with the number of terrestrial CAM species probably 10-fold greater. Still unresolved is the question why the large stem-succulent life - form is absent from the native Australian flora even though exotic large cacti have successfully invaded and established in Australia. PMID:27088716

  9. Primary colonization and breakdown of igneous rocks by endemic, succulent elephant trees ( Pachycormus discolor) of the deserts in Baja California, Mexico

    Science.gov (United States)

    Bashan, Yoav; Vierheilig, Horst; Salazar, Bernardo G.; de-Bashan, Luz E.

    2006-07-01

    Trees growing in rocks without soil are uncommon. In two arid regions in Baja California, Mexico, field surveys found large numbers of rock-colonizing elephant trees ( Pachycormus discolor (Benth.) Coville ex Standl. (Mexican name: copalquin) growing in igneous rocks (granite and basalt) as primary colonizers without the benefit of soil or with a very small amount of soil generated by their own growth. Many adult trees broke large granite boulders and were capable of wedging, growing in, and colonizing rocks and cliffs made of ancient lava flows. This is the first record of a tree species, apart from the previously recorded cacti, capable of primary colonization of rocks and rock rubble in hot deserts.

  10. Anatomical investigation on Cactaceae Juss.: a historical retrospect

    Directory of Open Access Journals (Sweden)

    Galina V. Kalashnyk

    2014-04-01

    Full Text Available Cactaceae consists of perennial stem succulents with diverse morphology. Due the distinctive structure and form the interest of researchers to this group of plants is increasing nowadays. The present paper provides an overview of published data concerning anatomical studies on the family Cactaceae since the mid-nineteenth century to our days. It is important to consider that recent interest in this field does not reduce, while the number of studies dealing with the structure and features of seedlings, the effect of various environmental factors on them is uprising. Such studies have a great practical importance for introduction and reintroduction of cacti, as well as for determination of their adaptive characteristics to environmental conditions.

  11. Thermal evaporation synthesis of zinc oxide nanowires

    Science.gov (United States)

    Xing, Y. J.; Xi, Z. H.; Zhang, X. D.; Song, J. H.; Wang, R. M.; Xu, J.; Xue, Z. Q.; Yu, D. P.

    2005-04-01

    High quality ZnO nanowires were synthesized at high temperature without using heterogenous catalysts. The nanowires had a uniform prismatic shape and were grown in a cacti-like morphology. Characterizations of the products by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy showed that the ZnO nanowires were single crystalline and of high purity. An intensive exciton emission was observed around 3.25 eV from the ZnO nanowires at room temperature. The growth mechanism was discussed based on the experimental conditions and the ZnO crystal growth habits. This growth method can be used to prepare other metal oxide nanowires.

  12. Boltzmann Samplers, P\\'olya Theory, and Cycle Pointing

    CERN Document Server

    Bodirsky, Manuel; Kang, Mihyun; Vigerske, Stefan

    2010-01-01

    We introduce a general method to count unlabeled combinatorial structures and to efficiently generate them at random. The approach is based on pointing unlabeled structures in an "unbiased" way that a structure of size n gives rise to n pointed structures. We extend Polya theory to the corresponding pointing operator, and present a random sampling framework based on both the principles of Boltzmann sampling and on P\\'olya operators. All previously known unlabeled construction principles for Boltzmann samplers are special cases of our new results. Our method is illustrated on several examples: in each case, we provide enumerative results and efficient random samplers. The approach applies to unlabeled families of plane and nonplane unrooted trees, and tree-like structures in general, but also to families of graphs (such as cacti graphs and outerplanar graphs) and families of planar maps.

  13. Structured cone arrays for continuous and effective collection of micron-sized oil droplets from water.

    Science.gov (United States)

    Li, Kan; Ju, Jie; Xue, Zhongxin; Ma, Jie; Feng, Lin; Gao, Song; Jiang, Lei

    2013-01-01

    Environmental protection agencies and the petroleum industry require effective methods to separate micron-sized oil droplets from water. However, for most existing separation methods, phase separation occurs in the oil-water mixture. The remaining micron-scale oil droplets, which are not affected by phase separation, are difficult to handle with conventional methods on a large scale because of either a lack of separation ability or drawbacks in throughput capacity. Here we develop an oleophilic array of conical needle structures for the collection of micron-sized oil droplets, inspired by the collection of similar sized water droplets on conical cactus spines. Underwater, these structures mimic cacti and can capture micron-sized oil droplets and continuously transport them towards the base of the conical needles. Materials with this structure show obvious advantages in micron-sized oil collection with high continuity and high throughput. PMID:23921355

  14. Rotons and Slitons in a Magnetic Cactus: Dynamical Phyllotaxis

    Science.gov (United States)

    Nisoli, Cristiano; Gabor, Nathaniel

    2009-10-01

    Phyllotaxis, the study of mathematical patterns in the arrangement of leaves on stems, spines on cacti, petals on flowers, et cetera, fascinated mankind since the dawn of times. Similar patterns emerge in the the statics of simple physical systems. Here we reproduce experimentally the striking number-theoretical patterns found in the phyllotaxis of living beings in the statics of a simple mechanical apparatus. Then we show that its dynamics reveal unusual excitations beyond botany: multiple classical rotons and a large family of interconverting topological solitons. Applications at different scales and in different areas of physics are proposed and discussed. [4pt] [1] C. Nisoli et al, Phys. Rev. Lett. 102, 186103 (2009).[0pt] [2] C. Nisoli Phys. Rev. E 80, 026110 (2009).

  15. Epidermal characteristics in some representatives of Cactoideae (Cactaceae

    Directory of Open Access Journals (Sweden)

    Galina V. Kalashnyk

    2015-05-01

    Full Text Available In this paper we analyzed the epidermis of 6-month old representatives of 11 species of the subfamily Cactoideae. The epidermal cells of examined species have sprawled and elongated projections with a sinuous outlines. Most of plants have large epidermal cells, whose number per unit area considerably varies. Stomatal index of the studied species is small and very small. Size of stomata is variation of 32,5±0,5×24,9±0,7 in Astrophytum myriostigma to 43,2±0,6×36,1±0,5 in Rebutia flavistyla. Large stomata are typical for three species of cacti. All examined species have paracytic stomata. The small prismatic crystals are in epidermal cells of three species. Astrophytum myriostigma and Mammillaria prolifera have papillaes and trichomes on the surface.

  16. Divergence in olfactory host plant preference in D. mojavensis in response to cactus host use.

    Science.gov (United States)

    Date, Priya; Dweck, Hany K M; Stensmyr, Marcus C; Shann, Jodi; Hansson, Bill S; Rollmann, Stephanie M

    2013-01-01

    Divergence in host adaptive traits has been well studied from an ecological and evolutionary perspective, but identification of the proximate mechanisms underlying such divergence is less well understood. Behavioral preferences for host plants are often mediated by olfaction and shifts in preference may be accompanied by changes in the olfactory system. In this study, we examine the evolution of host plant preferences in cactophilic Drosophila mojavensis that feeds and breeds on different cacti throughout its range. We show divergence in electrophysiological responses and olfactory behavior among populations with host plant shifts. Specifically, significant divergence was observed in the Mojave Desert population that specializes on barrel cactus. Differences were observed in electrophysiological responses of the olfactory organs and in behavioral responses to barrel cactus volatiles. Together our results suggest that the peripheral nervous system has changed in response to different ecological environments and that these changes likely contribute to divergence among D. mojavensis populations. PMID:23936137

  17. Shape-controlled synthesis of ZnO architectures

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Debao [College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Song, Caixia; Hu, Zhengshui [College of Materials Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China)

    2008-01-15

    Several ZnO nanoarchitectures have been selectively prepared through hydrothermal method including urchin-shaped, flower-shaped, butterfly-shaped, and cacti-shaped microstructures. The influence of reaction temperature and the concentration of amphiphilic copolymer on the morphologies and shapes of ZnO samples have been studied. The samples were characterized using XRD, TEM, and SEM. It was found that ZnO nanorods or their assemblies were fabricated at higher temperature, whereas ZnO nanosheet architectures were produced at lower temperature. These flower-shaped architectures possess high BET surface area of 27.43 m{sup 2}/g. Room temperature UV-VIS and PL spectra of the as-obtained ZnO nanoarchitectures have been examined. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Exact results for the spherical model with competing interactions on the Bethe lattice

    Science.gov (United States)

    Pimpinelli, Alberto; Cassi, Davide

    1991-02-01

    We extend to next-nearest-neighbor (NNN) interactions a technique which allows the exact solution of the spherical model of Berlin and Kac on a general discrete geometrical structure (a graph). We give the solution when the graph is a Bethe lattice. The model shows collinear (ferromagnetic or antiferromagnetic) long-range order at low temperature when NNN interactions favor the same order as nearest-neighbor ones, while it is disordered at any finite temperature when competition exceeds a critical value. For vanishing nearest-neighbor interaction the lattice decouples in two independent Cayley cacti; if the exchange on each sublattice is ferromagnetic, the model becomes ordered at a nonzero temperature, while antiferromagnetic exchange gives again disorder at any temperature.

  19. Thermal evaporation synthesis of zinc oxide nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Y.J. [Peking University, Department of Electronics, Beijing (China); Peking University, School of Physics, Electron Microscopy Laboratory, and State Key Laboratory for Mesoscopic Physics, Beijing (China); Xi, Z.H.; Zhang, X.D.; Song, J.H.; Xue, Z.Q. [Peking University, Department of Electronics, Beijing (China); Wang, R.M.; Xu, J.; Yu, D.P. [Peking University, School of Physics, Electron Microscopy Laboratory, and State Key Laboratory for Mesoscopic Physics, Beijing (China)

    2005-04-01

    High quality ZnO nanowires were synthesized at high temperature without using heterogenous catalysts. The nanowires had a uniform prismatic shape and were grown in a cacti-like morphology. Characterizations of the products by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy showed that the ZnO nanowires were single crystalline and of high purity. An intensive exciton emission was observed around 3.25 eV from the ZnO nanowires at room temperature. The growth mechanism was discussed based on the experimental conditions and the ZnO crystal growth habits. This growth method can be used to prepare other metal oxide nanowires. (orig.)

  20. Cyclic $A_\\infty$ Algebras and Deligne's Conjecture

    CERN Document Server

    Ward, Benjamin C

    2011-01-01

    First we describe a class of homotopy Frobenius algebras via cyclic operads which we call cyclic $A_\\infty$ algebras. We then define a suitable new combinatorial operad which acts on the Hochschild cochains of such an algebra in a manner which encodes the homotopy BV structure. Moreover we show that this operad is equivalent to the cellular chains of a certain topological (quasi)-operad of CW complexes whose constituent spaces form a homotopy associative version of the Cacti operad of Voronov. These cellular chains thus constitute a chain model for the framed little disks operad, proving a cyclic $A_\\infty$ version of Deligne's conjecture. This chain model contains the minimal operad of Kontsevich and Soibelman as a suboperad and restriction of the action to this suboperad recovers their results in the unframed case. Additionally this proof recovers the work of Kaufmann in the case of a strict Frobenius algebra.

  1. Sex-specific triacylglycerides are widely conserved in Drosophila and mediate mating behavior.

    Science.gov (United States)

    Chin, Jacqueline S R; Ellis, Shane R; Pham, Huong T; Blanksby, Stephen J; Mori, Kenji; Koh, Qi Ling; Etges, William J; Yew, Joanne Y

    2014-01-01

    Pheromones play an important role in the behavior, ecology, and evolution of many organisms. The structure of many insect pheromones typically consists of a hydrocarbon backbone, occasionally modified with various functional oxygen groups. Here we show that sex-specific triacylclyerides (TAGs) are broadly conserved across the subgenus Drosophila in 11 species and represent a novel class of pheromones that has been largely overlooked. In desert-adapted drosophilids, 13 different TAGs are secreted exclusively by males from the ejaculatory bulb, transferred to females during mating, and function synergistically to inhibit courtship from other males. Sex-specific TAGs are comprised of at least one short branched tiglic acid and a long linear fatty acyl component, an unusual structural motif that has not been reported before in other natural products. The diversification of chemical cues used by desert-adapted Drosophila as pheromones may be related to their specialized diet of fermenting cacti. PMID:24618898

  2. Alcohol dehydrogenase polymorphism in barrel cactus populations of Drosophila mojavensis.

    Science.gov (United States)

    Cleland, S; Hocutt, G D; Breitmeyer, C M; Markow, T A; Pfeiler, E

    1996-07-01

    Starch gel electrophoresis revealed that the alcohol dehydrogenase (ADH-2) locus was polymorphic in two populations (from Agua Caliente, California and the Grand Canyon, Arizona) of cactophilic Drosophila mojavensis that utilize barrel cactus (Ferocactus acanthodes) as a host plant. Electromorphs representing products of a slow (S) and a fast (F) allele were found in adult flies. The frequency of the slow allele was 0.448 in flies from Agua Caliente and 0.659 in flies from the Grand Canyon. These frequencies were intermediate to those of the low (Baja California peninsula, Mexico) and high (Sonora, Mexico and southern Arizona) frequency Adh-2S populations of D. mojavensis that utilize different species of host cacti. PMID:8765684

  3. A novel method of genomic DNA extraction for Cactaceae1

    Science.gov (United States)

    Fehlberg, Shannon D.; Allen, Jessica M.; Church, Kathleen

    2013-01-01

    • Premise of the study: Genetic studies of Cactaceae can at times be impeded by difficult sampling logistics and/or high mucilage content in tissues. Simplifying sampling and DNA isolation through the use of cactus spines has not previously been investigated. • Methods and Results: Several protocols for extracting DNA from spines were tested and modified to maximize yield, amplification, and sequencing. Sampling of and extraction from spines resulted in a simplified protocol overall and complete avoidance of mucilage as compared to typical tissue extractions. Sequences from one nuclear and three plastid regions were obtained across eight genera and 20 species of cacti using DNA extracted from spines. • Conclusions: Genomic DNA useful for amplification and sequencing can be obtained from cactus spines. The protocols described here are valuable for any cactus species, but are particularly useful for investigators interested in sampling living collections, extensive field sampling, and/or conservation genetic studies. PMID:25202521

  4. Immediate skin and mucosal symptoms from pot plants and vegetables in gardeners and greenhouse workers.

    Science.gov (United States)

    Paulsen, E; Skov, P S; Andersen, K E

    1998-10-01

    Short-lived occupational skin symptoms of irritant or urticarial nature were commonly reported among 253 attendants in a clinical study on occupational dermatitis in Danish gardeners and greenhouse workers. Aimed prick or scratch-patch testing for immediate skin and mucosal symptoms was performed in 105 persons with plants as is. 35 persons (33%) had at least 1 positive reaction and a family history of, or personal, atopy was significantly more prevalent among these compared to attendants with negative reactions. Positive histamine release tests made immunologic etiology probable in Schlumbergera cacti, Stephanotis floribunda, Euphorbia pulcherrima and Gerbera reactions. Other new species implicated in immediate-type reactions included Ficus pumila, Gardenia jasminoides, Hibiscus rosa-sinensis, Campanula, Columnea, Epipremnum aureum, Pelargonium and Primula vulgaris. Because of the high prevalence of short-lived skin symptoms and because contact urticaria may present itself as a dermatitis, it is recommended that one supplement patch tests with tests for immediate reactions. PMID:9817221

  5. Enhancing Leakage Power in CPU Cache Using Inverted Architecture

    Directory of Open Access Journals (Sweden)

    Bilal A. Shehada

    2013-02-01

    Full Text Available Power consumption is an increasingly pressing problem in modern processor design. Since the on-chip caches usually consume a significant amount of power so power and energy consumption parameters have become one of the most important design constraint. It is one of the most attractive targets for power reduction. This paper presents an approach to enhance the dynamic power consumption of CPU cache using inverted cache architecture. Our assumption tries to reduce dynamic write power dissipation based on number of ones and zeros in the in-coming cache block data using bit to indicate is the block is mostly one or zero. This architecture reduces the dynamic write power by 17 %. We use Proteus Simulator to test that proposed circuit and performed the experiments on a modified version of the cacti6.0 simulator.

  6. Measurement of the flow past a cactus-inspired cylinder

    Science.gov (United States)

    Oweis, Ghanem F.; El-Makdah, Adnan M.

    2012-11-01

    Desert cacti are tall cylindrical plants characterized by longitudinal u- or v-shaped grooves that run parallel to the plant axis, covering its surface area. We study the wake flow modifications resulting from the introduction of cactus-inspired surface grooves to a circular cylinder. Particle image velocimetry PIV is implemented in a wind tunnel to visualize and quantify the wake flow from a cactus cylinder in cross wind and an equivalent circular cylinder at Re O(1E5). The cactus wake exhibits superior behavior over its circular counterpart as seen from the mean and turbulent velocity profiles. The surface flow within the grooves is also probed to elucidate the origins of the wake alterations. Lastly, we use simple statistical analysis based only on the wake velocity fields, under the assumption of periodicity of the shedding, to recover the time varying flow from the randomly acquired PIV snapshots.

  7. Cereus peruvianus (Koubo new cactus fruit for the world

    Directory of Open Access Journals (Sweden)

    Yosef Mizrahi

    2014-03-01

    Full Text Available Several different species of the columnar cacti of the genera Stenocereus and Pachycereus, were introduced into different semi-arid ecozones in Israel and most of these efforts were of disappointing outcomes, the only exception being the Cereus peruvianus (L. Miller,which bore plenty of fruits, some of them of good taste. The original seeds of this plant were obtained from the late Mr. Amram (Ron Kodish, who collected seeds from various private gardens in Southern California which bore fruits of reasonable qualities. The initial success of this species led us to initiate an intensive research study, and today it is already fruit-crop, marketed mainly in Israel under the name " Koubo" . This paper will describe our work of domestication of this new cactus fruit crop in Israel.

  8. The Cleavage Operad and String Topology of Higher Dimension

    CERN Document Server

    Bargheer, Tarje

    2010-01-01

    For a manifold N embedded inside euclidean space R^{n+1}, we produce a coloured operad that acts homologically on the space of maps from N to M, where M is a compact, oriented, smooth manifold. This generalizes the action of the Cacti operad, retrieving the Chas-Sullivan product by taking N to be the unit-circle in R^2. We go on to show that for S^n the unit sphere in R^{n+1}, the operad constructed is a coloured E_{n+1}-operad. This E_{n+1}-structure can finally be twisted by subgroups of the diffeomorphism group of S^n; taking SO(n+1) as a subgroup hereof procures higher-dimensional Batalin-Vilkovisky structures on the homology of the mapping space acted upon.

  9. Characterization of volatiles of necrotic Stenocereus thurberi and Opuntia littoralis and toxicity and olfactory preference of Drosophila melanogster, D. mojavensis wrigleyi, and D. mojavensis sonorensis to necrotic cactus volatiles.

    Science.gov (United States)

    Wright, Cynthia R; Setzer, William N

    2014-08-01

    Drosophila mojavensis wrigleyi and D. mojavensis sonorensis are geographically separated races of cactophilic fruit flies. D. mojavensis sonorensis inhabits the Sonoran Desert and utilizes necrotic rots of Stenocereus thurberi Engelm. as a food source and to oviposit while D. mojavensis wrigleyi inhabits Santa Catalina Island, California and utilizes the necrotic rots of Opuntia littoralis (Engelm.) Cockerell. The objectives of this study were to determine the volatile compositions of the necrotic cacti and to determine if the volatile components show either selective toxicity or attraction toward the fruit flies. The volatile chemical compositions of field-rot specimens of both necrotic cacti were obtained by dynamic headspace (purge-and-trap) and hydrodistillation techniques and analyzed by gas chromatography - mass spectrometry. The volatile fraction of necrotic S. thurberi early rot was dominated by carboxylic acids (84.8%) and the late rot by p-cresol (32.6% in the dynamic headspace sample and 55.9% in the hydrodistilled sample). O. littoralis volatiles were dominated by carboxylic acids (86% in the dynamic headspace sample and 89.1% in the hydrodistilled sample). Fifteen compounds that were identified in the necrotic rot volatiles were used to test insecticidal activity and olfactory preference on the cactophilic Drosophila species, as well as D. melanogaster. Differences in toxicity and olfactory preference were observed between the different taxa. Both races of D. mojavensis exhibited toxicity to benzaldehyde and 2-nonanone, while butanoic acid and palmitic acid were tolerated at high concentrations. D. m. wrigleyi demonstrated a greater olfactory preference for anisole, butanoic acid, 2-heptanone, and palmitic acid than did D. m. sonorensis, while D. m. sonorensis demonstrated a greater preference for hexadecane, octanoic acid, and oleic acid than did D. m. wrigleyi. PMID:25233605

  10. Chemopreventive effect of cactus (Opuntia humifusa) extracts: radical scavenging activity, pro-apoptosis, and anti-inflammatory effect in human colon (SW480) and breast cancer (MCF7) cells.

    Science.gov (United States)

    Kim, Jinhee; Jho, Kwang Hyun; Choi, Young Hee; Nam, Sang-Yong

    2013-04-30

    Cactus (Opuntia spp) is widely cultivated as a vegetable, fruit, and forage crop and has been used in traditional medicine in American Indian, Mexican, and Korean cultures. Accumulative evidence from both in vitro and in vivo studies using cacti suggests their biological and pharmacological activities, such as their anti-cancer and anti-inflammatory roles in different cancer cells. In this study, the Opuntia humifusa stem (OHS) was extracted with different solvents and screened for radical scavenging activity using 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS˙(+)) and 1,1-diphenyl-2-picryl hydrazyl (DPPH). In addition, the total phenolic and flavonoid contents of each extract were analyzed using the Folin-Ciocalteu method and high performance liquid chromatography, respectively. Further, the cacti's bioactive fractions were evaluated for cell cytotoxicity and to understand their mechanism of action on human colon cancer (SW480) and breast cancer (MCF7) cells. An ethyl acetate (EtOAc) extract exhibited the highest cytotoxicity and resulted in an up-regulated expression of the pro-apoptotic protein Bax (bcl-2 associated X protein) and a down-regulated expression of the anti-apoptotic protein Bcl2 in both SW480 and MCF7 cells. The apoptosis was mediated through activation of caspase 8, 9, and 3/7 activities as well as PARP cleavage in SW480 cells, while the same extract activated only a caspase 9 activity in MCF7 cells. Furthermore, incubation of cells with the EtOAc extract down-regulated the expression of inflammatory molecules such as cyclooxygenase-2 (COX2) and inducible nitric oxide synthase (iNOS) in SW480 cells but not in MCF7 cells. Taken together, these results suggest that SW480 colon cancer cells are more susceptible to bioactive compounds present in OHS and may have potential in the prevention of cancer through modulation of apoptosis markers and inhibition of inflammatory pathways. PMID:23435602

  11. Sobre la presencia de cactáceas naturalizadas en la costa meridional de Cataluña

    Directory of Open Access Journals (Sweden)

    Sanz-Elorza, Mario

    2004-06-01

    Full Text Available The authors report on the finding of eight new alien cacti naturalised in the Baix Camp (Tarragona. Three of these are new records for Europe, two are new records for Spain and one is a first record for Tarragona province. Two further species are not new floristic records however some revision of their status in Catalonia is required. Discussed is the extensive use of alien plant species in garden design in the area and the mildness of the local climatic conditions which has resulted in the greatest accumulation of naturalised cacti in Europe.En una riera de la comarca del Baix Camp (Tarragona hemos encontrado ocho especies de cactáceas alóctonas naturalizadas. De ellas, tres son nuevas para Europa, dos nuevas para España, una nueva para la provincia de Tarragona y, finalmente, otras dos sin ser novedad florística requieren aclaraciones en lo concerniente a su estatus en Cataluña. Este hallazgo representa la mayor biodiversidad de cactáceas citada hasta el momento para toda Cataluña, para toda la Península Ibérica e incluso para toda Europa. La introducción de especies exóticas en general y de cactáceas en particular se ve favorecida en esta comarca de la costa mediterránea por el desarrollo de una jardinería basada casi exclusivamente en elementos foráneos y en la existencia de una climatología muy favorable.

  12. A Study to Determine the Mental Models in Preschool Children’s Conceptualization of a Desert Environment

    Directory of Open Access Journals (Sweden)

    Berat AHİ

    2016-03-01

    Full Text Available This study aimed to determine mental models and identify codes (schemes used in conceptualizing a desert environment. The sample for this study consisted of 184 – out of a total population of 3,630 - children in preschool education in the central district of Kastamonu, Turkey. Within the scope of this study, the children were initially asked to draw a desert-themed picture, followed by a semi-structured interview to seek their opinions about the drawing and clarify what a desert environment meant to them. According to the findings, the children referred to 38 different codes relevant to the conceptualization of a desert environment; the most frequently used were the sun (f= 160, 86.9%, sand (f= 100, 54.3%, cacti (f= 74, 35.3% and camels (f= 52, 28.6%. During the interview phase, 33 children described a desert as a place where there is no life, although a significant number of the children (f= 65, 39.1% did describe a desert as a place where plants and animals live. Moreover, the sun and its rays were disproportionately bigger in size, in order to emphasize the excessive heat associated with the specific ecosystem found in a desert environment; to reinforce this, humans drenched in sweat, the absence of trees and the prevalence of cacti and exotic wildlife, including camels, scorpions and lizards, were all features of the children’s drawings. Based on these findings, it was inferred that the mental models in some of the children (f= 72, 39.1% were scientifically informed, with a degree of accuracy, about a desert environment. On the basis of the findings, it is considered that determining mental models in children in relation to different ecological concepts can be beneficial to teachers and curriculum programmers involved in environmental education.

  13. Viruses in laboratory-reared cactus moth, Cactoblastis cactorum (Lepidoptera: Pyralidae)

    International Nuclear Information System (INIS)

    The cactus moth, Cactoblastis cactorum (Lepidoptera: Pyralidae: Phycitinae), is a non-native species threatening a variety of native cacti, particularly endangered species of Opuntia (Zimmerman et al. 2001), on the coast of the Gulf of Mexico. Cactoblastis cactorum populations have expanded from Florida northward along the Atlantic coast as far as Charleston, SC, and westward along the Gulf of Mexico to Dauphin Island, south of Mobile, AL. It is feared that further movement to the west will allow C. cactorum to enter the US desert Southwest and Mexico, particularly the latter. Numerous cactus species, especially those of the genera Opuntia and Nopalea, are native to the U.S. and Mexico. Local economies based on agricultural and horticultural uses of cacti could be devastated by C. cactorum (Vigueras and Portillo 2001). A bi-national control program between the US and Mexico is being developed, utilizing the sterile insect technique (SIT). In the SIT program, newly emerged moths are irradiated with a 60Co source and released to mate with wild individuals. The radiation dose completely sterilizes the females and partially sterilizes the males. When irradiated males mate with wild females, the F1 progeny of these matings are sterile. In order for the SIT program to succeed, large numbers of moths must be reared from egg to adult on artificial diet in a quarantined rearing facility (Carpenter et al. 2001). Irradiated insects must then be released in large numbers at the leading edge of the invasive population and at times which coincide with the presence of wild individuals available for mating. Mortality from disease in the rearing colony disrupts the SIT program by reducing the numbers of insects available for release

  14. New insecticides for control of the invasive cactus moth, Cactoblastis cactorum (Lepidoptera: Pyralidae), in Florida

    International Nuclear Information System (INIS)

    Full text: Cactoblastis cactorum (Berg) has successfully controlled several species of invasive prickly pear cacti (Cactaceae: Opuntioideae - Opuntia) in Australia and in many other parts of the world. However, in 1989 C. cactorum was detected in the Florida Keys. Its rapid spread along the Atlantic and Gulf Coasts has raised concerns about its unavoidable impact on native Opuntia cacti in the southern United States and in Mexico. The current infestation of C. cactorum in Florida is affecting native Opuntia species distributed throughout large expanses of natural lands (O. stricta [Haworth] Haworth, O. humifusa [Raf.] Raffinesque and O. pusilla [Haworth] Nutall), as well as ornamental cactus plants (O. ficus-indica [L.] Miller and O. stricta) in urban settings. Even though chemical control would not be a practical or environmentally responsible tactic to protect the millions of ha of natural Opuntia vegetation, insecticide controls should be evaluated for their potential use in urban settings and in culturally managed plantings of Opuntia (nurseries, backyards, landscaped public lands) either alone or in combination with other suppression tactics. Furthermore, insecticides could be used to treat ornamental Opuntia in nursery settings to ensure that no infested plants are being transported and sold to the public. We conducted laboratory assays of nine products registered for use on ornamentals in Florida for their ovicidal and larvicidal activity against the invasive cactus moth C. cactorum. One hundred percent mortality (or 0% survival) of one-day-old eggs was obtained when egg stick sections were treated with cypermethrin, spinosad or imidacloprid. These products were equally as effective when assayed against eggs that were fully embryonated (28 days old) or when cladodes of O. stricta were exposed to neonates 24 hours after dipping or to cladodes that were dipped and stored for 30 days before exposure. When Bacillus thuringiensis (Dipel) was used to prevent

  15. What magnitude are observed non-target impacts from weed biocontrol?

    Science.gov (United States)

    Suckling, David Maxwell; Sforza, René François Henri

    2014-01-01

    A systematic review focused by plant on non-target impacts from agents deliberately introduced for the biological control of weeds found significant non-target impacts to be rare. The magnitude of direct impact of 43 biocontrol agents on 140 non-target plants was retrospectively categorized using a risk management framework for ecological impacts of invasive species (minimal, minor, moderate, major, massive). The vast majority of agents introduced for classical biological control of weeds (>99% of 512 agents released) have had no known significant adverse effects on non-target plants thus far; major effects suppressing non-target plant populations could be expected to be detectable. Most direct non-target impacts on plants (91.6%) were categorized as minimal or minor in magnitude with no known adverse long-term impact on non-target plant populations, but a few cacti and thistles are affected at moderate (n = 3), major (n = 7) to massive (n = 1) scale. The largest direct impacts are from two agents (Cactoblastis cactorum on native cacti and Rhinocyllus conicus on native thistles), but these introductions would not be permitted today as more balanced attitudes exist to plant biodiversity, driven by both society and the scientific community. Our analysis shows (as far as is known), weed biological control agents have a biosafety track record of >99% of cases avoiding significant non-target impacts on plant populations. Some impacts could have been overlooked, but this seems unlikely to change the basic distribution of very limited adverse effects. Fewer non-target impacts can be expected in future because of improved science and incorporation of wider values. Failure to use biological control represents a significant opportunity cost from the certainty of ongoing adverse impacts from invasive weeds. It is recommended that a simple five-step scale be used to better communicate the risk of consequences from both action (classical biological control) and no

  16. Introduced and invasive cactus species: a global review.

    Science.gov (United States)

    Novoa, Ana; Le Roux, Johannes J; Robertson, Mark P; Wilson, John R U; Richardson, David M

    2014-01-01

    Understanding which species are introduced and become invasive, and why, are central questions in invasion science. Comparative studies on model taxa have provided important insights, but much more needs to be done to unravel the context dependencies of these findings. The cactus family (Cactaceae), one of the most popular horticultural plant groups, is an interesting case study. Hundreds of cactus species have been introduced outside their native ranges; a few of them are among the most damaging invasive plant species in the world. We reviewed the drivers of introductions and invasions in the family and seek insights that can be used to minimize future risks. We compiled a list of species in the family and determined which have been recorded as invasive. We also mapped current global distributions and modelled the potential global distributions based on distribution data of known invasive taxa. Finally, we identified whether invasiveness is phylogenetically clustered for cacti and whether particular traits are correlated with invasiveness. Only 57 of the 1922 cactus species recognized in this treatment have been recorded as invasive. There are three invasion hotspots: South Africa (35 invasive species recorded), Australia (26 species) and Spain (24 species). However, there are large areas of the world with climates suitable for cacti that are at risk of future invasion-in particular, parts of China, eastern Asia and central Africa. The invasive taxa represent an interesting subset of the total species pool. There is a significant phylogenetic signal: invasive species occur in 2 of the 3 major phylogenetic clades and in 13 of the 130 genera. This phylogenetic signal is not driven by human preference, i.e. horticultural trade, but all invasive species are from 5 of the 12 cactus growth forms. Finally, invasive species tend to have significantly larger native ranges than non-invasive species, and none of the invasive species are of conservation concern in their

  17. What magnitude are observed non-target impacts from weed biocontrol?

    Directory of Open Access Journals (Sweden)

    David Maxwell Suckling

    Full Text Available A systematic review focused by plant on non-target impacts from agents deliberately introduced for the biological control of weeds found significant non-target impacts to be rare. The magnitude of direct impact of 43 biocontrol agents on 140 non-target plants was retrospectively categorized using a risk management framework for ecological impacts of invasive species (minimal, minor, moderate, major, massive. The vast majority of agents introduced for classical biological control of weeds (>99% of 512 agents released have had no known significant adverse effects on non-target plants thus far; major effects suppressing non-target plant populations could be expected to be detectable. Most direct non-target impacts on plants (91.6% were categorized as minimal or minor in magnitude with no known adverse long-term impact on non-target plant populations, but a few cacti and thistles are affected at moderate (n = 3, major (n = 7 to massive (n = 1 scale. The largest direct impacts are from two agents (Cactoblastis cactorum on native cacti and Rhinocyllus conicus on native thistles, but these introductions would not be permitted today as more balanced attitudes exist to plant biodiversity, driven by both society and the scientific community. Our analysis shows (as far as is known, weed biological control agents have a biosafety track record of >99% of cases avoiding significant non-target impacts on plant populations. Some impacts could have been overlooked, but this seems unlikely to change the basic distribution of very limited adverse effects. Fewer non-target impacts can be expected in future because of improved science and incorporation of wider values. Failure to use biological control represents a significant opportunity cost from the certainty of ongoing adverse impacts from invasive weeds. It is recommended that a simple five-step scale be used to better communicate the risk of consequences from both action (classical biological

  18. Ecological and evolutionary conditions for fruit abortion to regulate pollinating seed-eaters and increase plant production

    Science.gov (United States)

    Holland, J. Nathaniel; DeAngelis, Donald L.

    2002-01-01

    Coevolved mutualisms, such as those between senita cacti, yuccas, and their respective obligate pollinators, benefit both species involved in the interaction. However, in these pollination mutualisms the pollinator's larvae impose a cost on plants through consumption of developing seeds and fruit. The effects of pollinators on benefits and costs are expected to vary with the abundance of pollinators, because large population sizes result in more eggs and larval seed-eaters. Here, we develop the hypothesis that fruit abortion, which is common in yucca, senita, and plants in general, could in some cases have the function of limiting pollinator abundance and, thereby, increasing fruit production. Using a general steady-state model of fruit production and pollinator dynamics, we demonstrate that plants involved in pollinating seed-eater mutualisms can increase their fecundity by randomly aborting fruit. We show that the ecological conditions under which fruit abortion can improve plants fecundity are not unusual. They are best met when the plant is long-lived, the population dynamics of the pollinator are much faster than those of the plant, the loss of one fruit via abortion kills a larva that would have the expectation of destroying more than one fruit through its future egg laying as an adult moth, and the effects of fruit abortion on pollinator abundance are spatially localized. We then use the approach of adaptive dynamics to find conditions under which a fruit abortion strategy based on regulating the pollinator population could feasibly evolve in this type of plant–pollinator interaction.

  19. Comparison of the ionizing radiation effects on cochineal, annatto and turmeric natural dyes

    Science.gov (United States)

    Cosentino, Helio M.; Takinami, Patricia Y. I.; del Mastro, Nelida L.

    2016-07-01

    As studies on radiation stability of food dyes are scarce, commercially important natural food grade dyes were evaluated in terms of their sensitivity against gamma ionizing radiation. Cochineal, annatto and turmeric dyes with suitable concentrations were subjected to increasing doses up to 32 kGy and analyzed by spectrophotometry and capillary electrophoresis. The results showed different pattern of absorbance versus absorbed dose for the three systems. Carmine, the glucosidal coloring matter from the scale insect Coccus cacti L., Homoptera (cochineal) remained almost unaffected by radiation up to doses of about 32 kGy (absorbance at 494 nm). Meanwhile, at that dose, a plant-derived product annatto or urucum (Bixa orellana L.) tincture presented a nearly 58% reduction in color intensity. Tincture of curcumin (diferuloylmethane) the active ingredient in the eastern spice turmeric (Curcuma longa) showed to be highly sensitive to radiation when diluted. These data shall be taken in account whenever food products containing these food colors were going to undergo radiation processing.

  20. The polymorphic weddellite crystals in three species of Cephalocereus (Cactaceae).

    Science.gov (United States)

    Bárcenas-Argüello, María-Luisa; Gutiérrez-Castorena, Ma C-del-Carmen; Terrazas, Teresa

    2015-10-01

    Mineral inclusions in plant cells are genetically regulated, have an ecological function and are used as taxonomic characters. In Cactaceae, crystals in epidermal and cortical tissues have been reported; however, few studies have conducted chemical and morphological analyses on these crystals, and even fewer have reported non-mineral calcium to determine its systematic value. Cephalocereus apicicephalium, C. totolapensis and C. nizandensis are Cactaceae species endemic to the Isthmus of Tehuantepec, Mexico with abundant epidermal prismatic crystals. In the present study, we characterize the mineral cell inclusions, including their chemical composition and their morphology, for three species of Cephalocereus. Crystals of healthy branches of the three species were isolated and studied. The crystals were identified by X-ray diffraction (XRD), their morphology was described using a petrographic and scanning electron microscope (SEM), and their elemental composition was measured with Energy Dispersive X-ray (EDXAR). The three species synthesized weddellite with different degrees of hydration depending on the species. The optical properties of calcium oxalate crystals were different from the core, which was calcium carbonate. We observed a large diversity of predominantly spherical forms with SEM. EDXAR analysis detected different concentrations of Ca and significant amounts of elements, such as Si, Mg, Na, K, Cl, and Fe, which may be related to the edaphic environment of these cacti. The occurrence of weddellite is novel for the genus according to previous reports. The morphological diversity of the crystals may be related to their elemental composition and may be a source of phylogenetic characters. PMID:26070169

  1. Abelian Sandpile Model on Randomly Rooted Graphs and Self-Similar Groups

    CERN Document Server

    Matter, Michel

    2011-01-01

    The main result of this paper is a rigorous proof of criticality and an explicit computation of critical exponents for the decay of avalanches in the Abelian sandpile model (ASM) on finite approximations of a large family of infinite graphs. We begin by introducing the notion of criticality of the ASM for limits of finite graphs in local convergence, which naturally leads to the question about criticality of the ASM in the random weak limit. Our main technical ingredient is a sufficient condition for almost sure criticality of the ASM on sequences of finite cacti (i.e., separable graphs whose blocks are cycles or single edges) under the assumption that the random weak limit is almost surely 1-ended. Examples that allow explicit computations of the critical exponents come from actions of finitely generated groups on regular rooted trees, by automorphisms. Restricting the action to the consecutive levels of the tree defines a sequence of finite graphs whose limits in the local convergence are orbital Schreier g...

  2. Historias de los Bosques que alguna vez fueron pastizales: la producción de la naturaleza en la frontera argentino-paraguaya

    Directory of Open Access Journals (Sweden)

    Gastón R. Gordillo

    2010-03-01

    Full Text Available In this article, I combine recent approaches to the making of places with an older theoretical tradition concerned with the social production of nature. In particular, I examine how seemingly “natural” landscapes are made and unmade by social practice and by the spatial cleavages created by an international border. My analysis focuses on the legacy of the landscape transformations that affected the western Argentinean Chaco on the Pilcomayo River in the early twentieth century, when the expansion of cattle raising on an indigenous frontier caused the disappearance of grasslands and the expansion of forests of hardwoods, cacti, and shrubs. In particular, I analyze how, among the Toba living in this region, their social memory, expectations, and historical experience of the local landscapes are intertwined with the territorial divide created by the nearby border between Argentina and Paraguay, which has created very different landscapes on each side of the border. Overall, this paper analyzes how the making of places is entangled with the socio-historical production of nature and with the culturally and spatially productive territoriality of borderlines.

  3. Separation of amaranthine-type betacyanins by ion-pair high-speed countercurrent chromatography.

    Science.gov (United States)

    Jerz, Gerold; Gebers, Nadine; Szot, Dominika; Szaleniec, Maciej; Winterhalter, Peter; Wybraniec, Slawomir

    2014-05-30

    Betacyanins, red-violet plant pigments, were fractionated by ion-pair high-speed countercurrent chromatography (IP-HSCCC) from leaves extract of Iresine lindenii Van Houtte, an ornamental plant of the family Amaranthaceae. An HSCCC solvent system consisting of TBME-1-BuOH-ACN-H2O (1:3:1:5, v/v/v/v) was applied using ion-pair forming heptafluorobutyric acid (HFBA). Significantly different elution profiles of betacyanin diastereomeric pairs (derivatives based on betanidin and isobetanidin) observed in the HSCCC in comparison to HPLC systems indicate a complementarity of both techniques' fractionation capabilities. The numerous diastereomeric pairs can be selectively separated from each other using the HSCCC system simplifying the pigment purification process. Apart from the three well known highly abundant pigments (amaranthine, betanin and iresinin I) together with their isoforms, three new acylated (feruloylated and sinapoylated) betacyanins as well as known pigment hylocerenin (previously isolated from cacti fruits) were characterized in the plant for the first time and they are new for the whole Amaranthaceae family. PMID:24767836

  4. Ecological genomics of host shifts in Drosophila mojavensis.

    Science.gov (United States)

    Matzkin, Luciano M

    2014-01-01

    Advances in next-generation sequencing technologies have liberated our dependency on model laboratory species for answering genomic and transcriptomic level questions. These new techniques have dramatically expanded our breadth of study organisms and have allowed the analysis of species from diverse ecological environments. One such species is the cactophilic Drosophila mojavensis that inhabits the deserts of western North America. These insects feed and develop in the necrotic cacti, feeding largely on the microflora of the necrotic plant tissues. Drosophila mojavensis is composed of four geographically and ecologically separated populations. Each population (Baja California peninsula, mainland Sonoran Desert, Mojave Desert and Santa Catalina Island) utilizes the necrotic tissues of distinct cactus species. The differences in the nutritional and chemical composition of the necroses include a set of toxic compounds to which resident population must adapt. These ecological differences have facilitated many of the life history, behavior, physiological and genetic differences between the cactus host populations. Genomic resources have allowed investigators to examine the genomic and transcriptional level changes associated with the local adaptation of the four D. mojavensis populations, thereby providing further understanding of the genetic mechanism of adaptation and its role in the divergence of ecologically distinct populations. PMID:24277303

  5. Cancer preventive and curative attributes of plants of the Cactaceae family: a review.

    Science.gov (United States)

    Harlev, Eli; Nevo, Eviatar; Solowey, Elaine; Bishayee, Anupam

    2013-06-01

    The ever-increasing occurrence of cancer and the severe side effects and limited efficacy of current cancer chemotherapy based on chemical drugs shift the attention toward drugs of plant origin. The Cactaceae family comprises more than 1500 species, but until recently only a few of them have been tested for their chemopreventive and anticancer attributes, leaving a wide unexplored area still waiting for researchers to investigate. Considering this fact, and also the promising results obtained with the relatively few plants of this family already tested, it should justly be expected that some plants of the Cactaceae family yet unexplored might possess outstanding anticancer attributes, exceeding those displayed by the plants already tested. This review presents in vitro and in vivo experimental evidence on cancer chemopreventive and therapeutic potential of bioactive phytoconstituents and extracts derived from cactus plants. It also examines the underlying biochemical and molecular mechanisms involved in the antineoplastic effects of plants of the Cactaceae family. Current limitation and future directions of research towards effective use of cacti to develop efficient and side effect-free future cancer-preventive and anticancer drugs are also discussed. PMID:23702905

  6. Phyllotactic pattern formation in early stages of cactus ontogeny

    Directory of Open Access Journals (Sweden)

    Edyta M. Gola

    2011-04-01

    Full Text Available Representatives of the family Cactaceae are characterized by a wide range of phyllotaxis. To assess the origin of this diversity, early stages of phyllotactic pattern formation were examined in seedlings. The analysis of the sequence of areole initiation revealed intertribal differences. In seedlings from the Trichocereeae (Gymnocalycium, Rebutia and Notocacteae (Parodia tribes, two opposite cotyledonal areoles developed as the first elements of a pattern. Usually, next pair of areoles was initiated perpendicularly to cotyledonal areoles, starting the decussate pattern. This pattern was subsequently transformed into bijugate or into simple spiral phyllotaxis. In seedlings from the Cacteae tribe (Mammillaria and Thelocactus, cotyledonal areoles were never observed and the first areoles always appeared in the space between cotyledons. It was either areole pair (mainly in Mammillaria, starting a decussate pattern, or a single areole (mainly in Thelocactus quickly followed by areoles spirally arranged, usually in accordance with the main Fibonacci phyllotaxis. Differences in the initial stages of pattern formation do not fully explain the phyllotaxis diversity in mature cacti. Only two, the most common phyllotactic patterns occurred in the early development of studied seedlings, i.e. the main Fibonacci and the decussate pattern. Discrepancy in the range of phyllotactic spectra in seedlings and in mature plants suggests that phyllotaxis diversity emerges during further plant growth. Initial phyllotactic transformations, occurring already in the very early stages, indicate great plasticity of cactus growth and seem to support the hypothesis of the ontogenetic increase of phyllotaxis diversity due to transformations.

  7. Cactaceae do Vale do Rio Jequitinhonha (Minas Gerais Cactaceae of Jequitinhonha river valley (Minas Gerais

    Directory of Open Access Journals (Sweden)

    Nigel P Taylor

    1991-07-01

    Full Text Available Durante as primeiras coletas relacionadas ao Projeto "Cactaceae no Brasil Oriental", ficou provada a grande diversidade de espércies dessa família na região do vale médio do Rio Jequitinhonha, tendo sido visitadas as localidades de Itinga, Itaobim e Pedra Azul. Foram coletadas 21 espécies distribuídas entre os gêneros Pereskia, Opuntia, Tacinga, Pseudoacanthocereus, Arrojadoa, Brasilicereus, Cereus, Coleocephalocereus, Melocactus, Pilosocereus e Selenicereus, representando as três subfamílias de Cactaceae, cujas afinidades taxonômicas e padrões de distribuição geográfica são discutidos a seguir.During an initial visit to collect material for the projected "Cacti of Eastern Brazil", a remarkable great diversity of species of Cactaceae in the region of middle drainage of the Rio Jequitinhonha (mainly in the localities of Itinga, Itaobim and Pedra Azul was noted. Twenty one species in the genera Pereskia, Opuntia, Tacinga, Pseudocanthocereus, Arrojadoa, Brasilicereus, Cereus, Coloecephalocereus, Melocactus, Pilosocereus e Selenicereus representing all three subfamilies of Cactaceae were recorted. The phytogeographic affinities of the Cactaceae from this region are discussed.

  8. Shared origins of a key enzyme during the evolution of C4 and CAM metabolism.

    Science.gov (United States)

    Christin, Pascal-Antoine; Arakaki, Monica; Osborne, Colin P; Bräutigam, Andrea; Sage, Rowan F; Hibberd, Julian M; Kelly, Steven; Covshoff, Sarah; Wong, Gane Ka-Shu; Hancock, Lillian; Edwards, Erika J

    2014-07-01

    CAM and C4 photosynthesis are two key plant adaptations that have evolved independently multiple times, and are especially prevalent in particular groups of plants, including the Caryophyllales. We investigate the origin of photosynthetic PEPC, a key enzyme of both the CAM and C4 pathways. We combine phylogenetic analyses of genes encoding PEPC with analyses of RNA sequence data of Portulaca, the only plants known to perform both CAM and C4 photosynthesis. Three distinct gene lineages encoding PEPC exist in eudicots (namely ppc-1E1, ppc-1E2 and ppc-2), one of which (ppc-1E1) was recurrently recruited for use in both CAM and C4 photosynthesis within the Caryophyllales. This gene is present in multiple copies in the cacti and relatives, including Portulaca. The PEPC involved in the CAM and C4 cycles of Portulaca are encoded by closely related yet distinct genes. The CAM-specific gene is similar to genes from related CAM taxa, suggesting that CAM has evolved before C4 in these species. The similar origin of PEPC and other genes involved in the CAM and C4 cycles highlights the shared early steps of evolutionary trajectories towards CAM and C4, which probably diverged irreversibly only during the optimization of CAM and C4 phenotypes. PMID:24638902

  9. Identifying the demographic processes relevant for species conservation in human-impacted areas: does the model matter?

    Science.gov (United States)

    González, Edgar J; Rees, Mark; Martorell, Carlos

    2013-02-01

    The identification of the demographic processes responsible for the decline in population growth rate (λ) in disturbed areas would allow conservation efforts to be efficiently directed. Integral projection models (IPMs) are used for this purpose, but it is unclear whether the conclusions drawn from their analysis are sensitive to how functional structures (the functions that describe how survival, growth and fecundity vary with individual size) are selected. We constructed 12 IPMs that differed in their functional structure by combining two reproduction models and three functional expressions (generalized linear, cubic and additive models), each with and without simplification. Models were parameterized with data from two populations of two endangered cacti subject to different disturbance intensities. For each model, we identified the demographic processes that most affected λ in the presence of disturbance. Simulations were performed on artificial data and analyzed as above to assess the generality of the results. In both empirical and simulated data, the same processes were identified as making the largest contribution to changes in λ regardless of the functional structure. The major differences in the results were due to misspecification of the fecundity functions, whilst functional expression and model simplification had lesser effects. Therefore, as long as the demographic attributes of the species are well known and incorporated into the model, IPMs will robustly identify the processes that most affect the growth of populations subject to disturbance, making them a reliable tool for developing conservation strategies. PMID:22955702

  10. Natural hybrid organic-inorganic photovoltaic devices

    Science.gov (United States)

    De Padova, Paola; Lucci, Massimiliano; Olivieri, Bruno; Quaresima, Claudio; Priori, Sandro; Francini, Roberto; Grilli, Antonio; Hricovini, Karol; Davoli, Ivan

    2009-06-01

    Natural hybrid organic-inorganic photovoltaic devices based on TiO 2 have been realized. Chlorophyll A (from anacystis nidulans algae), chlorophyll B (from spinach), carmic acid (from insect Coccus cacti L.), synthetic trans- β-carotene, natural fresh picked Morus nigra, and their mixtures have been used as an organic photo active layer to fabricate photovoltaic prototypes. In order to reduce the charge's interfacial recombination, different thicknesses (5-45 nm) of Si layers, subsequently oxidized in air, were inserted between the TiO 2 and chlorophyll B. Scanning electron microscopy of TiO 2 and Si/TiO 2 systems shows the coexistence at least of four classes of nanoparticles of 60, 100, 150 and 250 nm in size. Auger electron spectroscopy of the Si L 2,3V V transition demonstrates the presence of silica and SiO x suboxides. Photocurrent measurements versus radiation wavelength in the range 300-800 nm exhibit different peaks according to the absorption spectra of the organic molecules. All realized photovoltaic devices are suitable for solar light electric energy conversion. Those made of a blend of all organic molecules achieved higher current and voltage output. The Si/TiO 2-based devices containing chlorophyll B exhibited an enhanced photocurrent response with respect to those with TiO 2 only.

  11. Phylogeography of the Cactophilic Drosophila and Other Arthropods Associated with Cactus Necroses in the Sonoran Desert

    Directory of Open Access Journals (Sweden)

    Therese A. Markow

    2011-05-01

    Full Text Available Studies on the population genetics, phylogenetic relationships, systematics and evolution of arthropods that inhabit necrotic tissue of cacti in the Sonoran Desert of North America are reviewed. These studies have focused upon several species of insects (orders Diptera and Coleoptera and arachnids (order Pseudoscorpiones. For most taxa studied, little genetic structure and high dispersal ability are found in populations inhabiting the mainland and Baja California peninsula regions of the Sonoran Desert, consistent with the availability of the rotting cactus microhabitat which is patchily distributed and ephemeral. There is evidence, however, that the Gulf of California, which bisects the Sonoran Desert, has played a role in limiting gene flow and promoting speciation in several taxa, including histerid beetles, whereas other taxa, especially Drosophila nigrospiracula and D. mettleri, apparently are able to freely cross the Gulf, probably by taking advantage of the Midriff Islands in the northern Gulf as dispersal “stepping stones”. Genetic evidence has also been found for historical population expansions dating to the Pleistocene and late Pliocene in several taxa. Overall, these studies have provided important insights into how arthropods with different life history traits, but generally restricted to a necrotic cactus microhabitat, have evolved in an environmentally harsh and tectonically active region. In addition, they suggest some taxa for further, and more detailed, hypothesis driven studies of speciation.

  12. A Cross-Layer Framework for Designing and Optimizing Deeply-Scaled FinFET-Based Cache Memories

    Directory of Open Access Journals (Sweden)

    Alireza Shafaei

    2015-08-01

    Full Text Available This paper presents a cross-layer framework in order to design and optimize energy-efficient cache memories made of deeply-scaled FinFET devices. The proposed design framework spans device, circuit and architecture levels and considers both super- and near-threshold modes of operation. Initially, at the device-level, seven FinFET devices on a 7-nm process technology are designed in which only one geometry-related parameter (e.g., fin width, gate length, gate underlap is changed per device. Next, at the circuit-level, standard 6T and 8T SRAM cells made of these 7-nm FinFET devices are characterized and compared in terms of static noise margin, access latency, leakage power consumption, etc. Finally, cache memories with all different combinations of devices and SRAM cells are evaluated at the architecture-level using a modified version of the CACTI tool with FinFET support and other considerations for deeply-scaled technologies. Using this design framework, it is observed that L1 cache memory made of longer channel FinFET devices operating at the near-threshold regime achieves the minimum energy operation point.

  13. The Knee: Theory and Experiment

    Science.gov (United States)

    Yodh, Gaurang B.

    2006-10-01

    A review of current status of theoretical paradigm and results of direct and indirect experiments to study cosmic rays through the knee region are presented and discussed. There is general agreement that the knee is around a PeV and that it reflects a rigidity cutoff. The composition of cosmic rays in the knee region is mixed and changing with energy. The two direct experiments, JACEE and RUNJOB with measurements in the 100 TeV per particle to 1000 TeV per particle and with similar exposures do not agree. While JACEE indicates a increase in langlelnArangle from its low energy value of 1.5 to a value closer to 3 , the RUNJOB experiment sees no change in the composition albeit with large uncertainty. Of the indirect experiments, KASKADE, SPASEAMANDA, HEGRA-Airobic, CACTI, TUNKA and Tibet favor ''Heavy'' composition above the knee and beyond. The KASKADE energy range extends to 100 PeV where their analysis indicates iron dominance. KASKADE does not see a proton rigidity cutoff until about 3 PeV, while Tibet measures a steepening of the proton slope at a few hundred TeV. BLANCA and DICE favor little composition change or a change towards a proton dominated composition around 10 PeV. We need experiments with much better mass resolution in the energy range of the knee and a more quantitative understanding of the hadron production in the forward region at these energies to make definitive progress.

  14. Molecular phylogeny and character evolution in terete-stemmed Andean opuntias (Cactaceae-Opuntioideae).

    Science.gov (United States)

    Ritz, C M; Reiker, J; Charles, G; Hoxey, P; Hunt, D; Lowry, M; Stuppy, W; Taylor, N

    2012-11-01

    The cacti of tribe Tephrocacteae (Cactaceae-Opuntioideae) are adapted to diverse climatic conditions over a wide area of the southern Andes and adjacent lowlands. They exhibit a range of life forms from geophytes and cushion-plants to dwarf shrubs, shrubs or small trees. To confirm or challenge previous morphology-based classifications and molecular phylogenies, we sampled DNA sequences from the chloroplast trnK/matK region and the nuclear low copy gene phyC and compared the resulting phylogenies with previous data gathered from nuclear ribosomal DNA sequences. The here presented chloroplast and nuclear low copy gene phylogenies were mutually congruent and broadly coincident with the classification based on gross morphology and seed micro-morphology and anatomy. Reconstruction of hypothetical ancestral character states suggested that geophytes and cushion-forming species probably evolved several times from dwarf shrubby precursors. We also traced an increase of embryo size at the expense of the nucellus-derived storage tissue during the evolution of the Tephrocacteae, which is thought to be an evolutionary advantage because nutrients are then more rapidly accessible for the germinating embryo. In contrast to these highly concordant phylogenies, nuclear ribosomal DNA data sampled by a previous study yielded conflicting phylogenetic signals. Secondary structure predictions of ribosomal transcribed spacers suggested that this phylogeny is strongly influenced by the inclusion of paralogous sequence probably arisen by genome duplication during the evolution of this plant group. PMID:22877645

  15. Genetic structure of Kurtzmaniella cleridarum, a cactus flower beetle yeast of the Sonoran and Mojave Deserts: speciation by distance?

    Science.gov (United States)

    Lachance, Marc-André; Perri, Ami M; Farahbakhsh, Amy S; Starmer, William T

    2013-11-01

    We studied 95 isolates of the yeast species Kurtzmaniella cleridarum recovered from nitidulid beetles collected in flowers of cacti of the Sonoran Desert of southern Arizona and the Mojave Desert of California. They were characterized on the basis of mating type and ten polymorphic DNA markers in relation to their geographic distribution. Although all loci appeared to be free of strong linkage, the recovered haplotypes represented but a small fraction of possible combinations, indicating that abundant asexual reproduction of local genotypes accounts for much of population growth, even though the yeast is capable of sexual recombination in nature. Much of the genetic differentiation took place at the local level, indicating that gene flow across the various localities is limited. However, a relationship exists between overall genetic differentiation and geography over long distances. We estimated that populations separated by c. 1300 km would share no alleles in common and that such a separation might be enough to favor the onset of speciation. PMID:23865628

  16. Seed size and photoblastism in species belonging to tribe Cacteae (Cactaceae).

    Science.gov (United States)

    Rojas-Aréchiga, Mariana; Mandujano, María C; Golubov, Jordan K

    2013-05-01

    The response of seed germination towards light and the relationship to seed traits has been studied particularly well in tropical forests. Several authors have shown a clear adaptive response of seed size and photoblastism, however, the evolutionary significance of this relationship for species inhabiting arid environments has not been fully understood and only some studies have considered the response in a phylogenetic context. We collected seeds from 54 cacti species spread throughout the tribe Cacteae to test whether there was correlated evolution of photoblastism, seed traits and germination using a reconstructed phylogeny of the tribe. For each species we determined the photoblastic response under controlled conditions, and seed traits, and analyzed the results using phylogenetically independent contrasts. All studied species were positive photoblastic contrasting with the basal Pereskia suggesting an early evolution of this trait. Seeds from basal species were mostly medium-sized, diverging into two groups. Seeds tend to get smaller and lighter suggesting an evolution to smaller sizes. No evidence exists of a relationship between seed size and photoblastic response suggesting that the photoblastic response within members of this tribe is not adaptive though it is phylogenetically fixed and that is coupled with environmental cues that fine tune the germination response. PMID:23065043

  17. Haptoglobin genotype predicts development of coronary artery calcification in a prospective cohort of patients with type 1 diabetes

    Directory of Open Access Journals (Sweden)

    Simpson Melissa

    2011-11-01

    Full Text Available Abstract Background Coronary artery disease has been linked with genotypes for haptoglobin (Hp which modulates extracorpuscular hemoglobin. We hypothesized that the Hp genotype would predict progression of coronary artery calcification (CAC, a marker of subclinical atherosclerosis. Methods CAC was measured three times in six years among 436 subjects with type 1 diabetes and 526 control subjects participating in the Coronary Artery Calcification in Type 1 Diabetes (CACTI study. Hp typing was performed on plasma samples by polyacrylamide gel electrophoresis. Results The Hp 2-2 genotype predicted development of significant CAC only in subjects with diabetes who were free of CAC at baseline (OR: 1.95, 95% CI: 1.07-3.56, p = 0.03, compared to those without the Hp 2-2 genotype, controlling for age, sex, blood pressure and HDL-cholesterol. Hp 2 appeared to have an allele-dose effect on development of CAC. Hp genotype did not predict CAC progression in individuals without diabetes. Conclusions Hp genotype may aid prediction of accelerated coronary atherosclerosis in subjects with type 1 diabetes.

  18. Evolution of male genitalia: environmental and genetic factors affect genital morphology in two Drosophila sibling species and their hybrids

    Directory of Open Access Journals (Sweden)

    Hasson Esteban

    2007-05-01

    Full Text Available Abstract Background The rapid evolution of genital morphology is a fascinating feature that accompanies many speciation events. However, the underlying patterns and explanatory processes remain to be settled. In this work we investigate the patterns of intraspecific variation and interspecific divergence in male genitalic morphology (size and shape in the cactophilic sibling species Drosophila buzzatii and D. koepferae. Genital morphology in interspecific hybrids was examined and compared to the corresponding parental lines. Results Despite of being siblings, D. buzzatii and D. koepferae showed contrasting patterns of genital morphological variation. Though genitalic size and shape variation have a significant genetic component in both species, shape varied across host cacti only in D. buzzatii. Such plastic expression of genital shape is the first evidence of the effect of rearing substrate on genitalic morphology in Drosophila. Hybrid genital morphology was not intermediate between parental species and the morphological resemblance to parental strains was cross-dependent. Conclusion Our results suggest the evolution of different developmental networks after interspecific divergence and the existence of a complex genetic architecture, involving genetic factors with major effects affecting genital morphology.

  19. Myxomycetes associated with Cactaceae in sub-humid (agreste and semi-arid (sertão regions of Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    Inaldo do Nascimento Ferreira

    2011-06-01

    Full Text Available Studies that indicate the presence of Myxomycetes in arid and semi-arid regions of the planet have revealed new taxons and high species diversity. In those environments, the Myxomycetes occupy special microhabitats like those offered by succulent plants. Aiming to expand the knowledge of species that occur in semi-arid environments we investigated the occurrence of Myxomycetes on Cereus jamacaru (mandacaru, Melocactus bahiensis (coroa de frade, Opuntia ficus-indica (palma forrageira and Pilocereus gounellei (xique-xique – cacti that compose the natural landscape of the sub-humid (agreste and semi-arid (sertão regions of Pernambuco, Brazil. We obtained 158 specimens of Myxomycetes (106 field collections; 52 in moist chamber cultures, representing 16 species distributed in nine genera, with high taxonomic diversity (S/G= 0.63-1.5. All of the identified species are new records for the municipalities studied. Comatricha pulchella, Didymium nigripes and Physarum bogoriense are mentioned for the first time in Caatinga areas in the state of Pernambuco, and Didymium squamulosum and Physarum echinosporum are new records for this biome. Physarum compressum and Badhamia melanospora were the most abundant and frequent species, characterized as constant in the studied myxobiota.

  20. Contrasting Plasticity in Ovariole Number Induced by A Dietary Effect of the Host Plants between Cactophilic Drosophila Species.

    Science.gov (United States)

    Peluso, Daniela; Soto, Eduardo M; Kreiman, Lucas; Hasson, Esteban; Mensch, Julián

    2016-01-01

    Under the preference-performance hypothesis, natural selection will favor females that choose oviposition sites that optimize the fitness of their offspring. Such a preference-performance relationship may entail important consequences mainly on fitness-related traits. We used the well-characterized cactus-Drosophila system to investigate the reproductive capacity in the pair of sibling species D. buzzatii and D. koepferae reared in two alternative host plants. According to our hypothesis, ovariole number (as a proxy of reproductive capacity) depends on host plant selection. Our results indicate that the capacity of D. buzzatii showed to be mild, only increasing the number of ovarioles by as much as 10% when reared in its preferred host. In contrast, D. koepferae exhibited a similar reproductive capacity across host cacti, even though it showed a preference for its primary host cactus. Our study also revealed that D. buzzatii has a larger genetic variation for phenotypic plasticity than its sibling, although ovariole number did not show clear-cut differences between species. We will discuss the weak preference-performance pattern observed in these cactophilic species in the light of nutritional and toxicological differences found between the natural host plants. PMID:27213456

  1. Orientations of terminal cladodes of Platyopuntias

    Energy Technology Data Exchange (ETDEWEB)

    Nobel, P.S.

    1982-01-01

    The orientations of terminal unshaded cladodes of 23 species of platyopuntias were observed in North America, South America, Australia, and Israel. When the seasonality of rainfall favored cladode development in the winter and the site was located above 27/sup 0/N, the cladodes tended to face north-south (five cases, P < .001 for each). In all other cases without topographical blockage of incoming radiation, the tendency was to face east-west. For example, terminal cladodes of Opuntia phaeacantha var. discata and O. stricta tended to face north-south in Israel but east-west in the United States (P > .001). Such dissimilar orientation patterns also occurred for cladodes of 0. chlorotica at two sites in the Sonoran Desert and for O. basilaris var. basilaris developing at different seasons at a single site. Contrary to previously published observations, cladodes of O. ficus-indica and O. compressa had a significant tendency to orient (P > .001). When topographical features affected the direction of prevailing photosynthetically active radiation (PAR), the preferred orientation of terminal cladodes was changed accordingly. The preferred direction always maximized the interception of PAR, which is often a limiting factor in the productivity of cacti, even in a putatively high radiation environment.

  2. Alien plant species list and distribution for Camdeboo National Park, Eastern Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    Mmoto L. Masubelele

    2009-01-01

    Full Text Available Protected areas globally are threatened by the potential negative impacts that invasive alien plants pose, and Camdeboo National Park (CNP, South Africa, is no exception. Alien plants have been recorded in the CNP since 1981, before it was proclaimed a national park by South African National Parks in 2005. This is the first publication of a list of alien plants in and around the CNP. Distribution maps of some of the first recorded alien plant species are also presented and discussed. To date, 39 species of alien plants have been recorded, of which 13 are invasive and one is a transformer weed. The majority of alien plant species in the park are herbaceous (39% and succulent (24% species. The most widespread alien plant species in the CNP are Atriplex inflata (= A. lindleyi subsp. inflata, Salsola tragus (= S. australis and cacti species, especially Opuntia ficus-indica. Eradication and control measures that have been used for specific problematic alien plant species are described. Conservation implications: This article represents the first step in managing invasive alien plants and includes the collation of a species list and basic information on their distribution in and around the protected area. This is important for enabling effective monitoring of both new introductions and the distribution of species already present. We present the first species list and distribution information for Camdeboo National Park.

  3. Leaf and stem CO/sub 2/ uptake in the three subfamilies of the Cactaceae. [Pereskia aculeata; Pereskia grandifolia; Maihuenia poeppigii; Carnegiea gigantea; Ferocactus acanthodes; Coryphantha vivipara; Mammillaria dioica; Opuntia ficus-inidica; Pereskiopsis porteri; Quiabentia chacoensis; Austrocylindropuntia subulata

    Energy Technology Data Exchange (ETDEWEB)

    Nobel, P.S.; Hartsock, T.L.

    1986-04-01

    Net CO/sub 2/ uptake over 24-hour periods was examined for the leaves and for the stems of 11 species of cacti representing all three subfamilies. For Pereskia aculeata, Pereskia grandifolia, and Maihuenia poeppigii (subfamily Pereskioideae), all the net shoot CO/sub 2/ uptake was by the leaves and during the daytime. In contrast, for the leafless species Carnegiea gigantea, Ferocactus acanthodes, Coryphantha vivipara, and Mammillaria dioica (subfamily Cactoideae), all the shoot net CO/sub 2/ uptake was by the stems and at night. Similarly, for leafless Opuntia ficus-indica (subfamily Opuntioideae), all net CO/sub 2/ uptake occurred at night. For leafy members of the Opuntioideae (Pereskiopsis porteri, Quiabentia chacoensis, Austrocylindropuntia subulata), at least 88% of the shoot CO/sub 2/ uptake over 24 hours was by the leaves and some CO/sub 2/ uptake occurred at night. Leaves responded to the instantaneous level of photosynthetically active radiation (PAR) during the daytime, as occurs for C/sub 3/ plants, whereas nocturnal CO/sub 2/ uptake by stems of O. ficus-indica and F. acanthodes responded to the total daily PAR, as occurs for Crassulacean acid metabolism (CAM) plants. Thus, under the well-watered conditions employed, the Pereskioideae behaved as C/sub 3/ plants, the Cactoideae behaved as CAM plants, and the Opuntioideae exhibited characteristics of both pathways.

  4. Seasonal reliance on nectar by an insectivorous bat revealed by stable isotopes.

    Science.gov (United States)

    Frick, Winifred F; Shipley, J Ryan; Kelly, Jeffrey F; Heady, Paul A; Kay, Kathleen M

    2014-01-01

    Many animals have seasonally plastic diets to take advantage of seasonally abundant plant resources, such as fruit or nectar. Switches from insectivorous diets that are protein rich to fruits or nectar that are carbohydrate rich present physiological challenges, but are routinely done by insectivorous songbirds during migration. In contrast, insectivorous bat species are not known to switch diets to consume fruit or nectar. Here, we use carbon stable isotope ratios to establish the first known case of a temperate bat species consuming substantial quantities of nectar during spring. We show that pallid bats (Antrozous pallidus) switch from a diet indistinguishable from that of sympatric insectivorous bat species in winter (when no cactus nectar is present) to a diet intermediate between those of insectivorous bats and nectarivorous bats during the spring bloom of a bat-adapted cactus species. Combined with previous results that established that pallid bats are effective pollinators of the cardon cactus (Pachycereus pringlei), our results suggest that the interaction between pallid bats and cardon cacti represents the first-known plant-pollinator mutualism between a plant and a temperate bat. Diet plasticity in pallid bats raises questions about the degree of physiological adaptations of insectivorous bats for incorporation of carbohydrate-rich foods, such as nectar or fruit, into the diet. PMID:24276770

  5. Diversity of unavailable polysaccharides and dietary fiber in domesticated nopalito and cactus pear fruit (Opuntia spp.).

    Science.gov (United States)

    Peña-Valdivia, Cecilia Beatriz; Trejo, Carlos; Arroyo-Peña, V Baruch; Sánchez Urdaneta, Adriana Beatriz; Balois Morales, Rosendo

    2012-08-01

    The aim of this study was to quantify mucilages, pectins, hemicelluloses, and cellulose of nopalitos (edible, as vegetable, young cladodes of flat-stemmed spiny cacti) of most consumed Mexican cultivars, and sweet and acid cactus pear fruits of Opuntia spp. The hypothesis is that, regardless of their unavailable polysaccharides diversity, nopalitos and cactus pear fruits are rich sources of soluble and insoluble dietary fiber. Twelve cultivars of Opuntia spp. were used. Nopalitos had a significant variation in structural polysaccharides among the cultivars: mucilages (from 3.8 to 8.6% dry matter (DM)) averaged near a half of pectins content (from 6.1 to 14.2% DM) and tightly bound hemicelluloses (from 2.2 to 4.7% DM), which were the less abundant polysaccharides, amounted 50% of the loosely bound hemicelluloses (from 4.3 to 10.7% DM). Acid fruits (or 'xoconostle') had significantly higher unavailable polysaccharides content than sweet fruit, and contain similar proportions than nopalitos. Unavailable polysaccharides represent a high proportion of dry tissues of nopalitos and cactus pear fruits, composition of both of these soluble and insoluble polysaccharides (total dietary fiber) widely vary among cultivars without an evident pattern. Nopalitos and cactus pear fruit can be considered an excellent source of dietary fiber. PMID:22899620

  6. Water Relations and Low-Temperature Acclimation for Cactus Species Varying in Freezing Tolerance.

    Science.gov (United States)

    Goldstein, G.; Nobel, P. S.

    1994-02-01

    Opuntia ficus-indica and Opuntia streptacantha are widely cultivated cacti that can tolerate temperatures no lower than -10[deg]C, whereas Opuntia humifusa, which is native to southern Canada and the eastern United States, can tolerate -24[deg]C. As day/night air temperatures were decreased from 30/20 to 10/0[deg]C, the osmotic pressure increased 0.10 MPa for O. ficus-indica and O. streptacantha but 0.38 MPa for O. humifusa. The increases in osmotic pressures were due mostly to the synthesis of fructose, glucose, and sucrose. In addition, O. humifusa produced a substantial amount of mannitol during exposure to low temperatures. Substantial accumulation of sugars and mannitol in cells of O. humifusa may help prevent intracellular freeze dehydration and ice formation as well as provide noncolligative protection to its membranes. Mucilage was slightly higher in all three species at the lower temperatures. Extracellular nucleation of ice occurred closer to the equilibrium freezing temperature for plants at 10/0[deg]C compared with 30/20[deg]C, which could make the cellular dehydration more gradual and, thus, less damaging. Results from nuclear magnetic resonance indicated a restricted mobility of intracellular water at the lower temperatures, especially for O. humifusa, which is consistent with its lower water content and higher levels of low molecular weight solutes. PMID:12232118

  7. Diel flight pattern and flight performance of Cactoblastis cactorum (Lepidoptera: Pyralidae) measured on a flight mill: influence of age, gender, mating status, and body size.

    Science.gov (United States)

    Sarvary, Mark A; Bloem, Kenneth A; Bloem, Stephanie; Carpenter, James E; Hight, Stephen D; Dorn, Silvia

    2008-04-01

    Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) is an invasive herbivore that poses a serious risk to Opuntia cacti in North America. Knowledge of the flight behavior of the cactus moth is crucial for a better understanding of natural dispersal, and for both monitoring and control. We used computer-linked flight mills to investigate diel flight activity and flight performance in relation to gender, age, mating status, and body size. Maximal flight activity for both mated and unmated moths occurred during twilight, whereas flight activity was low during photophase. The total distance flown and the number of initiated flights within a diel cycle were higher in both unmated and mated females than in males, but the longest single flight was similar in both genders. These findings suggest that pheromone trap captures of males likely indicate the simultaneous presence of females and that mated females might even be in areas where males are not detected yet. Flight performance heterogeneity was large, with a small portion of the population (both males and females) performing long unbroken flights, whereas the majority made short flights. Females had higher pupal and adult body size and shorter longevity than males. A few individuals, particularly young mated females, flying long distances may be important for active spread of a population and the colonization of new habitats. Implications of this study in the control of the cactus moth by using the sterile insect technique are discussed. PMID:18459394

  8. Not all the infected develop the disease - A "Lotus and Cactus" model.

    Science.gov (United States)

    Pitchappan, Ramasamy M

    2016-06-01

    The immunogenetic dictum "not all the infected develop the disease" can best be explained by a "Lotus and Cactus" model. Lotuses grow in ponds and cacti in deserts: analogously, we can say that tubercle patient's lung (genetic makeup) functions as an ideal 'broth' for Mycobacterium tuberculosis (M.tb) germs to grow, but not the lungs of an endemic control. HLA association studies from Europe to Asia since 1983 till date, have shown a persistent HLA DR2 (15) association. Further, HLA DR2 and non-DR2 endemic controls showed disparate patterns of immune responses and gene expressions. The host and pathogen MHC diversities, Th1-Th2 paradigm and cytokine circuits all may play a crucial role in TB susceptibility. It is possible to decipher the protective immunity by controlling the known confounders - epidemiological, demographic, socio-biological and also host and pathogen diversities. This has become significant with our understanding on the 'out of Africa' migration and neolithic co-dispersal of M.tb with modern human. Divergence and expansion of various MHCs (eg HLA-DRB1*15, HLA-B*57) and non-MHC alleles in various continents might be responsible for the skewed transmission and distribution of the infectious diseases around the globe. The 'Lotus and Cactus' model proposed here exemplifies this. A holistic genetic epidemiology approach employing modern tools is the need of the hour to better understand infectious disease susceptibility. PMID:26611827

  9. Acoustic emissions correlated with hydration of Saguaro Cactus

    Science.gov (United States)

    Wardell, L. J.; Rowe, C. A.

    2013-12-01

    For some years it has been demonstrated that hardwood trees produce acoustic emissions during periods of drought, which arise from cavitation in the xylem as water is withdrawn. These emissions not only provide insights into the fluid transport behavior within these trees, but also the degree to which cavitation can proceed before inevitable tree mortality. Such studies can have significant impact on our understanding of forest die-off in the face of climate change. Plant mortality is not limited to woody trees, however, and it is not only the coniferous and deciduous forests whose response to climate and rainfall changes are important. In the desert Southwest we observe changes to survival rates of numerous species of flora. One of the most conspicuous of these plants is the iconic Saguaro Cactus (Carnegiea gigantean). These behemoths of the Sonoran Desert are very sensitive to small perturbations in their environment. Specifically, during the summer monsoon season when the cacti become well-hydrated, they can absorb hundreds of gallons of water within a very short time frame. We have obtained a juvenile saguaro on which we are conducting experiments to monitor acoustic emissions during hydration and dessication cycles. We will report on our observations obtained using piezoelectric ceramic accelerometers whose signals are digitized up to 44 Khz and recorded during hydration.

  10. Host plant adaptation in Drosophila mettleri populations.

    Science.gov (United States)

    Castrezana, Sergio; Bono, Jeremy M

    2012-01-01

    The process of local adaptation creates diversity among allopatric populations, and may eventually lead to speciation. Plant-feeding insect populations that specialize on different host species provide an excellent opportunity to evaluate the causes of ecological specialization and the subsequent consequences for diversity. In this study, we used geographically separated Drosophila mettleri populations that specialize on different host cacti to examine oviposition preference for and larval performance on an array of natural and non-natural hosts (eight total). We found evidence of local adaptation in performance on saguaro cactus (Carnegiea gigantea) for populations that are typically associated with this host, and to chemically divergent prickly pear species (Opuntia spp.) in a genetically isolated population on Santa Catalina Island. Moreover, each population exhibited reduced performance on the alternative host. This finding is consistent with trade-offs associated with adaptation to these chemically divergent hosts, although we also discuss alternative explanations for this pattern. For oviposition preference, Santa Catalina Island flies were more likely to oviposit on some prickly pear species, but all populations readily laid eggs on saguaro. Experiments with non-natural hosts suggest that factors such as ecological opportunity may play a more important role than host plant chemistry in explaining the lack of natural associations with some hosts. PMID:22493678

  11. Host plant adaptation in Drosophila mettleri populations.

    Directory of Open Access Journals (Sweden)

    Sergio Castrezana

    Full Text Available The process of local adaptation creates diversity among allopatric populations, and may eventually lead to speciation. Plant-feeding insect populations that specialize on different host species provide an excellent opportunity to evaluate the causes of ecological specialization and the subsequent consequences for diversity. In this study, we used geographically separated Drosophila mettleri populations that specialize on different host cacti to examine oviposition preference for and larval performance on an array of natural and non-natural hosts (eight total. We found evidence of local adaptation in performance on saguaro cactus (Carnegiea gigantea for populations that are typically associated with this host, and to chemically divergent prickly pear species (Opuntia spp. in a genetically isolated population on Santa Catalina Island. Moreover, each population exhibited reduced performance on the alternative host. This finding is consistent with trade-offs associated with adaptation to these chemically divergent hosts, although we also discuss alternative explanations for this pattern. For oviposition preference, Santa Catalina Island flies were more likely to oviposit on some prickly pear species, but all populations readily laid eggs on saguaro. Experiments with non-natural hosts suggest that factors such as ecological opportunity may play a more important role than host plant chemistry in explaining the lack of natural associations with some hosts.

  12. Transcriptional variation associated with cactus host plant adaptation in Drosophila mettleri populations.

    Science.gov (United States)

    Hoang, Kim; Matzkin, Luciano M; Bono, Jeremy M

    2015-10-01

    Although the importance of host plant chemistry in plant-insect interactions is widely accepted, the genetic basis of adaptation to host plants is not well understood. Here, we investigate transcriptional changes associated with a host plant shift in Drosophila mettleri. While D. mettleri is distributed mainly throughout the Sonoran Desert where it specializes on columnar cacti (Carnegiea gigantea and Pachycereus pringleii), a population on Santa Catalina Island has shifted to chemically divergent coastal prickly pear cactus (Opuntia littoralis). We compared gene expression of larvae from the Sonoran Desert and Santa Catalina Island when reared on saguaro (C. gigantea), coastal prickly pear and laboratory food. Consistent with expectations based on the complexity and toxicity of cactus relative to laboratory food, within-population comparisons between larvae reared on these food sources revealed transcriptional differences in detoxification and other metabolic pathways. The majority of transcriptional differences between populations on the cactus hosts were independent of the rearing environment and included a disproportionate number of genes involved in processes relevant to host plant adaptation (e.g. detoxification, central metabolism and chemosensory pathways). Comparisons of transcriptional reaction norms between the two populations revealed extensive shared plasticity that likely allowed colonization of coastal prickly pear on Santa Catalina Island. We also found that while plasticity may have facilitated subsequent adaptive divergence in gene expression between populations, the majority of genes that differed in expression on the novel host were not transcriptionally plastic in the presumed ancestral state. PMID:26384860

  13. Remote Sensing of Sonoran Desert Vegetation Structure and Phenology with Ground-Based LiDAR

    Directory of Open Access Journals (Sweden)

    Joel B. Sankey

    2014-12-01

    Full Text Available Long-term vegetation monitoring efforts have become increasingly important for understanding ecosystem response to global change. Many traditional methods for monitoring can be infrequent and limited in scope. Ground-based LiDAR is one remote sensing method that offers a clear advancement to monitor vegetation dynamics at high spatial and temporal resolution. We determined the effectiveness of LiDAR to detect intra-annual variability in vegetation structure at a long-term Sonoran Desert monitoring plot dominated by cacti, deciduous and evergreen shrubs. Monthly repeat LiDAR scans of perennial plant canopies over the course of one year had high precision. LiDAR measurements of canopy height and area were accurate with respect to total station survey measurements of individual plants. We found an increase in the number of LiDAR vegetation returns following the wet North American Monsoon season. This intra-annual variability in vegetation structure detected by LiDAR was attributable to a drought deciduous shrub Ambrosia deltoidea, whereas the evergreen shrub Larrea tridentata and cactus Opuntia engelmannii had low variability. Benefits of using LiDAR over traditional methods to census desert plants are more rapid, consistent, and cost-effective data acquisition in a high-resolution, 3-dimensional context. We conclude that repeat LiDAR measurements can be an effective method for documenting ecosystem response to desert climatology and drought over short time intervals and at detailed-local spatial scale.

  14. How specialised is bird pollination in the Cactaceae?

    Science.gov (United States)

    Gorostiague, P; Ortega-Baes, P

    2016-01-01

    Many cactus species produce 'bird' flowers; however, the reproductive biology of the majority of these species has not been studied. Here, we report on a study of the pollination of two species from the Cleistocactus genus, cited as an ornithophilous genus, in the context of the different ways in which they are specialised to bird pollination. In addition, we re-evaluate the level of specialisation of previous studies of cacti with bird pollination and evaluate how common phenotypic specialisation to birds is in this family. Both Cleistocactus species exhibited ornithophilous floral traits. Cleistocactus baumannii was pollinated by hummingbirds, whereas Cleistocactus smaragdiflorus was pollinated by hummingbirds and bees. Pollination by birds has been recorded in 27 cactus species, many of which exhibit ornithophilous traits; however, they show generalised pollination systems with bees, bats or moths in addition to birds being their floral visitors. Of all cactus species, 27% have reddish flowers. This trait is associated with diurnal anthesis and a tubular shape. Phenotypic specialisation to bird pollination is recognised in many cactus species; however, it is not predictive of functional and ecological specialisation in this family. PMID:25545418

  15. Internal seed dispersal by parrots: an overview of a neglected mutualism.

    Science.gov (United States)

    Blanco, Guillermo; Bravo, Carolina; Pacifico, Erica C; Chamorro, Daniel; Speziale, Karina L; Lambertucci, Sergio A; Hiraldo, Fernando; Tella, José L

    2016-01-01

    Despite the fact that parrots (Psitacifformes) are generalist apex frugivores, they have largely been considered plant antagonists and thus neglected as seed dispersers of their food plants. Internal dispersal was investigated by searching for seeds in faeces opportunistically collected at communal roosts, foraging sites and nests of eleven parrot species in different habitats and biomes in the Neotropics. Multiple intact seeds of seven plant species of five families were found in a variable proportion of faeces from four parrot species. The mean number of seeds of each plant species per dropping ranged between one and about sixty, with a maximum of almost five hundred seeds from the cacti Pilosocereus pachycladus in a single dropping of Lear's Macaw (Anodorhynchus leari). All seeds retrieved were small (parrot species were viable according to the tetrazolium test and germination experiments. The conservative results of our exploratory sampling and a literature review clearly indicate that the importance of parrots as endozoochorous dispersers has been largely under-appreciated due to the lack of research systematically searching for seeds in their faeces. We encourage the evaluation of seed dispersal and other mutualistic interactions mediated by parrots before their generalized population declines contribute to the collapse of key ecosystem processes. PMID:26925322

  16. Forecasting climate change impacts to plant community composition in the Sonoran Desert region

    Science.gov (United States)

    Munson, Seth M.; Webb, Robert H.; Belnap, Jayne; Hubbard, J. Andrew; Swann, Don E.; Rutman, Sue

    2012-01-01

    Hotter and drier conditions projected for the southwestern United States can have a large impact on the abundance and composition of long-lived desert plant species. We used long-term vegetation monitoring results from 39 large plots across four protected sites in the Sonoran Desert region to determine how plant species have responded to past climate variability. This cross-site analysis identified the plant species and functional types susceptible to climate change, the magnitude of their responses, and potential climate thresholds. In the relatively mesic mesquite savanna communities, perennial grasses declined with a decrease in annual precipitation, cacti increased, and there was a reversal of the Prosopis velutina expansion experienced in the 20th century in response to increasing mean annual temperature (MAT). In the more xeric Arizona Upland communities, the dominant leguminous tree, Cercidium microphyllum, declined on hillslopes, and the shrub Fouquieria splendens decreased, especially on south- and west-facing slopes in response to increasing MAT. In the most xeric shrublands, the codominant species Larrea tridentata and its hemiparasite Krameria grayi decreased with a decrease in cool season precipitation and increased aridity, respectively. This regional-scale assessment of plant species response to recent climate variability is critical for forecasting future shifts in plant community composition, structure, and productivity.

  17. An ant's-eye view of an ant-plant protection mutualism.

    Science.gov (United States)

    Lanan, M C; Bronstein, J L

    2013-07-01

    Ant protection of extrafloral nectar (EFN)-secreting plants is a common form of mutualism found in most habitats around the world. However, very few studies have considered these mutualisms from the ant, rather than the plant, perspective. In particular, a whole-colony perspective that takes into account the spatial structure and nest arrangement of the ant colonies that visit these plants has been lacking, obscuring when and how colony-level foraging decisions might affect tending rates on individual plants. Here, we experimentally demonstrate that recruitment of Crematogaster opuntiae (Buren) ant workers to the EFN-secreting cactus Ferocactus wislizeni (Englem) is not independent between plants up to 5 m apart. Colony territories of C. opuntiae are large, covering areas of up to 5,000 m(2), and workers visit between five and 34 EFN-secreting barrel cacti within the territories. These ants are highly polydomous, with up to 20 nest entrances dispersed throughout the territory and interconnected by trail networks. Our study demonstrates that worker recruitment is not independent within large polydomous ant colonies, highlighting the importance of considering colonies rather than individual workers as the relevant study unit within ant/plant protection mutualisms. PMID:23515612

  18. Ecology of Mabuya agilis (Raddi (Lacertilia, Scincidae at the restinga of Grumari, Rio de Janeiro, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Davor Vrcibradic

    2002-12-01

    Full Text Available Some aspects of the ecology of the skink Mabuya agilis (Raddi, 1823 at the restinga habitat of Grumari, in Rio de Janeiro, Brazil are studied. Most of the lizards were first sighted on the ground, though a few were using perches (mainly cacti up to 30 cm high. Mean body temperature in activity was 33.1 ± 2.4ºC and was significantly correlated to air temperature. There was sexual dimorphism in size (snout-vent length - SVL, with females growing larger than males. Frequency of broken tails was high overall (83% and did not differ between sexes. Females and males are sexually mature at 49 mm and 47 mm SVL, respectively. Brood size averaged 3.2 ± 1.0 (range 1-5 and was positively and significantly related to female SVL (r = 0.65, p = 0.001. Relative clutch mass (RCM of seven gravid females averaged 0.250 ± 0.042, being relatively low compared to those of other congeners. The diet of M. agilis was composed basically of arthropods, with relatively large and soft-bodied arthropods such as spiders, caterpillars and homopterans being the most important prey. The results of our work confirm and expand the knowledge of ecological tendencies previously observed for M. agilis in other areas.

  19. Model-based analysis supports interglacial refugia over long-dispersal events in the diversification of two South American cactus species.

    Science.gov (United States)

    Perez, M F; Bonatelli, I A S; Moraes, E M; Carstens, B C

    2016-06-01

    Pilosocereus machrisii and P. aurisetus are cactus species within the P. aurisetus complex, a group of eight cacti that are restricted to rocky habitats within the Neotropical savannas of eastern South America. Previous studies have suggested that diversification within this complex was driven by distributional fragmentation, isolation leading to allopatric differentiation, and secondary contact among divergent lineages. These events have been associated with Quaternary climatic cycles, leading to the hypothesis that the xerophytic vegetation patches which presently harbor these populations operate as refugia during the current interglacial. However, owing to limitations of the standard phylogeographic approaches used in these studies, this hypothesis was not explicitly tested. Here we use Approximate Bayesian Computation to refine the previous inferences and test the role of different events in the diversification of two species within P. aurisetus group. We used molecular data from chloroplast DNA and simple sequence repeats loci of P. machrisii and P. aurisetus, the two species with broadest distribution in the complex, in order to test if the diversification in each species was driven mostly by vicariance or by long-dispersal events. We found that both species were affected primarily by vicariance, with a refuge model as the most likely scenario for P. aurisetus and a soft vicariance scenario most probable for P. machrisii. These results emphasize the importance of distributional fragmentation in these species, and add support to the hypothesis of long-term isolation in interglacial refugia previously proposed for the P. aurisetus species complex diversification. PMID:27071846

  20. State of the Art on Cactus Additions in Alkaline Media as Corrosion Inhibitors

    Directory of Open Access Journals (Sweden)

    A. A. Torres-Acosta

    2012-01-01

    Full Text Available This research in progress includes results on the corrosion performance of reinforcing steel in alkaline media when two different dehydrated cacti (Opuntia ficus-indica—Nopal—and Aloe Vera were used as additions in pH 12.5 and 13.3 solutions and in concrete. The dehydrated cactus addition was mixed at different concentrations by either solution or cement mass (0.10%, 0.25%, 0.5%, 1.0%, and 2.0%. Half-cell potentials and LPR measurements were performed at different time periods to characterize the possible corrosion inhibiting effect of the cactus additions tested in such alkaline media. Results showed good corrosion inhibiting effect of dehydrated Nopal on reinforcing steel, in all tested solutions, when chloride ions are present. Aloe Vera did show also corrosion inhibiting improvements in some extent. The addition of such cactus led to an apparent formation of a denser and more packed oxide/hydroxide surface layer on the steel surface that decreased corrosion activity. This oxide/hydroxide layer growth was confirmed by microscopic evaluation of the metal surface layer performed at the end of the research program. The preliminary findings suggest that adding Nopal at concentrations between 1% and 2%, by mass, might be suitable for durability enhancing applications in alkaline media, especially in concrete structures.

  1. Carbon isotope ratios in crassulacean Acid metabolism plants: seasonal patterns from plants in natural stands.

    Science.gov (United States)

    Szarek, S R

    1976-09-01

    A year round study of photosynthesis and carbon isotope fractionation was conducted with plants of Opuntia phaeacantha Engelm. and Yucca baccata Torr. occurring in natural stands at elevations of 525, 970, 1450 and 1900 m. Plant water potentials and the daytime pattern of (14)CO(2) photosynthesis were similar for all cacti along the elevational gradient, despite significant differences in temperature regime and soil water status. Carbon isotope ratios of total tissue and soluble extract fractions were relatively constant throughtout the entire year. Additionally, the sigma(13)C values were similar in all plants of the same species along the elevational gradient, i.e. -12.5 +/- 0.86 per thousand for O. phaeacantha and -15.7 +/- 0.95 per thousand for Y. baccata. The results of this study indicate Crassulacean acid metabolism predominates as the major carbon pathway of these plants, which do not facultatively utilize the reductive pentose phosphate cycle of photosynthesis as the primary carboxylation reaction. PMID:16659680

  2. Are the vegetation structure and composition of the shrubby Caatinga free from edge influence? A estrutura e a composição da vegetação da Caatinga arbustiva são livres da influência de borda?

    Directory of Open Access Journals (Sweden)

    André Maurício de Melo Santos

    2008-12-01

    Full Text Available Edge influence, or edge effect, drives many biological changes in fragmented landscapes. This has been extensively studied in many forest ecosystems, but it remains to be described for the Brazilian Caatinga. Based on the biotic and physical conditions of the shrubby Caatinga, our prediction a priori was that this type of vegetation is free from edge influence in terms of vegetation structure and composition. We sampled shrubs, cacti and trees in twenty 200 m² plots on old edges (>60 yrs old and interior of a 690 ha fragment, partially isolated and surrounded by Opuntia ficus-indica cacti. Plant height, stem diameter at ground level, stem density, species richness and diversity were statistically equal between edge and interior habitats. Magnitude of edge influence varied from -0.027 to 0.027, indicating low ecological importance of edge creation for the measured variables. Additionally, floristic similarity between habitats was 90% and a principal component analysis showed that species composition varied in a similar manner at edges and interiors. These results indicate that the vegetation of the sampled fragment is not ecologically affected by the creation of edges and suggests that changes in physical conditions and resource availability after edge creation are not enough to eliminate established plants or to alter recruitment and survival of new individuals.A influência de borda, ou efeito de borda, leva a diversas alterações biológicas em paisagens fragmentadas. Embora muito estudada em ecossistemas florestais, a influência de borda permanece desconhecida para a Caatinga. Baseada nas condições físicas e biológicas da Caatinga arbustiva, nossa predição a priori foi que este tipo de vegetação não sofre influência de borda em termos de estrutura e composição de espécies. Nós amostramos arbustos, cactos e árvores em 20 parcelas de 200 m² em bordas antigas (> 60 anos de idade e interiores de um fragmento de 690 ha

  3. Analysis of the factors that affect the distribution and abundance of three Neobuxbaumia species (Cactaceae) that differ in their degree of rarity

    Science.gov (United States)

    Ruedas, Marcela; Valverde, Teresa; Zavala-Hurtado, José Alejandro

    2006-03-01

    We studied three species of columnar cacti in the genus Neobuxbaumia which differ in their degree of rarity: Neobuxbaumia macrocephala (the rarest), Neobuxbaumia tetetzo (intermediate), and Neobuxbaumia mezcalaensis (the most common). To investigate the ecological factors that limit their distribution and abundance, we surveyed 80 localities within the region of Tehuacan-Cuicatlán, in Central Mexico. At each locality we measured several environmental variables, and the density of the Neobuxbaumia populations present. We used a principal component analysis (PCA) to identify the factors that are associated to the presence/absence of each species. Additionally, we carried out multiple regressions between environmental variables and population density to test whether the variation in these variables was related to changes in abundance. The results show that factors significantly affecting the distribution of these species are mean annual temperature, altitude, rainfall, and soil properties such as texture and organic matter content. N. mezcalaensis reaches maximum population densities of 14,740 plants per ha (average density = 3943 plants per ha) and is associated with localities with relatively abundant rainfall. N. tetetzo shows maximum population densities of 14,060 plants per ha (average = 3070 plants per ha), and is associated with sites located at high latitudes and with high phosphorous content in the soil. The rarest species, N. macrocephala, shows maximum densities of 1180 plants per ha (average = 607 plants per ha) and is associated with localities with high soil calcium content. The distribution of this species is limited to sites with specific values of the environmental variables recorded, conferring it a high habitat specificity which accounts for its rarity.

  4. Condensation on slippery asymmetric bumps.

    Science.gov (United States)

    Park, Kyoo-Chul; Kim, Philseok; Grinthal, Alison; He, Neil; Fox, David; Weaver, James C; Aizenberg, Joanna

    2016-03-01

    Controlling dropwise condensation is fundamental to water-harvesting systems, desalination, thermal power generation, air conditioning, distillation towers, and numerous other applications. For any of these, it is essential to design surfaces that enable droplets to grow rapidly and to be shed as quickly as possible. However, approaches based on microscale, nanoscale or molecular-scale textures suffer from intrinsic trade-offs that make it difficult to optimize both growth and transport at once. Here we present a conceptually different design approach--based on principles derived from Namib desert beetles, cacti, and pitcher plants--that synergistically combines these aspects of condensation and substantially outperforms other synthetic surfaces. Inspired by an unconventional interpretation of the role of the beetle's bumpy surface geometry in promoting condensation, and using theoretical modelling, we show how to maximize vapour diffusion fluxat the apex of convex millimetric bumps by optimizing the radius of curvature and cross-sectional shape. Integrating this apex geometry with a widening slope, analogous to cactus spines, directly couples facilitated droplet growth with fast directional transport, by creating a free-energy profile that drives the droplet down the slope before its growth rate can decrease. This coupling is further enhanced by a slippery, pitcher-plant-inspired nanocoating that facilitates feedback between coalescence-driven growth and capillary-driven motion on the way down. Bumps that are rationally designed to integrate these mechanisms are able to grow and transport large droplets even against gravity and overcome the effect of an unfavourable temperature gradient. We further observe an unprecedented sixfold-higher exponent of growth rate, faster onset, higher steady-state turnover rate, and a greater volume of water collected compared to other surfaces. We envision that this fundamental understanding and rational design strategy can be

  5. Adaptability in stone tool use by wild capuchin monkeys (Sapajus libidinosus).

    Science.gov (United States)

    De Moraes, Bárbara Lins Caldas; Da Silva Souto, Antonio; Schiel, Nicola

    2014-10-01

    Capuchin monkeys are well known for population variation in the use of stone tools and the types of food items consumed. In order to determine adaptability in stone tool use, we investigated a never before studied population of wild capuchin monkey (Sapajus libidinosus) displaying terrestrial habits in a Caatinga environment. To carry out this study we recorded physical evidence of the use of stone tools as well as made direct observations through trap cameras. During a 15-month period, we studied a group of Sapajus libidinosus in Serra Talhada, Pernambuco, Brazil. In total, 257 anvils and 395 hammers were identified, characterized, and monitored. We identified five types of food items exploited at these "tool use sites": Syagrus oleracea (catolé palm), Manihot epruinosa (manioc), Pilosocereus pachycladus (facheiro), Tacinga inamoena (quípa), and Commiphora leptophloeos (imburana de cambão). Five hundred three video clips of capuchin monkeys were recorded, 43 of which involved the use of stone tools. The results indicated evidence of adaptability in tool use by the capuchins. We verified that the rigidity and size of the food item, along with the presence or absence of spines seem to influence the choice of stone tools made by the animals for processing the food. The recurring use of tools for the processing of cacti was especially noteworthy and it appears that the presence of spines predisposes the capuchins to use stones to process them. A significant difference was observed between the characteristics of the anvils and the weight of the hammers according to the food item consumed. The use of tools enabled the animals to access otherwise unavailable or difficult to acquire food items within a Caatinga habitat. Adaptability in the use of stone tools by the capuchin monkey population of Serra Talhada provides an example of the complexity that these primates demonstrate in food processing. PMID:24753103

  6. Tunable Diode Laser Measurements of Leaf-scale Carbon Isotope Discrimination and Ecosystem Respired Carbon and Oxygen Isotope Ratios in a Semi-arid Woodland

    Science.gov (United States)

    McDowell, N.; Chris, B.; Hanson, D.; Kern, S.; Meyer, C.; Pockman, W.; Powers, H.

    2005-12-01

    We present results and speculative interpretation of leaf-level carbon isotope discrimination and ecosystem respired carbon and oxygen isotope ratios from a semi-arid, C3/C4 woodland located in northern New Mexico, USA. Overstory leaf area index (LAI) is dominated by live juniper (Juniperus monosperma) trees with an LAI value of approximately 1.0 m2 per m2 ground area, and has a seasonally dynamic understory of mixed C3 forbs and C4 grasses and cacti, with a maximum LAI of 0.30 m2 per m2 ground area. Ecosystem respired carbon isotope ratios showed values characteristic of C3 dominated photosynthesis (Keeling plot intercepts of -35 to -22 per mil). Seasonal variation was typical of that found in wetter, C3 dominated forests, as was the dependence on climate (e.g. relationships with vapor pressure deficit, soil water content, and canopy conductance). Leaf-level carbon isotope discrimination of the junipers, measured by coupling a Li-Cor 6400 photosynthesis system to the TDL, provided discrimination-Ci and discrimination-vpd relationships consistent with measured ecosystem respired carbon isotope ratios. The oxygen isotope ratio of ecosystem respiration was dependent on rain water isotope composition, but was correlated with soil water content during rain-free periods. The cumulative effect of vapor pressure deficit after a rain event was tightly correlated with the oxygen isotope ratio of ecosystem respiration, suggesting the primary drivers are evaporative enrichment of soil water and perhaps nocturnal leaf enrichment. Instrument precision for carbon and oxygen isotope ratios of carbon dioxide is 0.06 to 0.18 per mil; however, overall precision is somewhat lower due to pressure and sampling effects.

  7. Premating isolation is determined by larval rearing substrates in cactophilic Drosophila mojavensis. X. Age-specific dynamics of adult epicuticular hydrocarbon expression in response to different host plants.

    Science.gov (United States)

    Etges, William J; de Oliveira, Cassia C

    2014-06-01

    Analysis of sexual selection and sexual isolation in Drosophila mojavensis and its relatives has revealed a pervasive role of rearing substrates on adult courtship behavior when flies were reared on fermenting cactus in preadult stages. Here, we assessed expression of contact pheromones comprised of epicuticular hydrocarbons (CHCs) from eclosion to 28 days of age in adults from two populations reared on fermenting tissues of two host cacti over the entire life cycle. Flies were never exposed to laboratory food and showed significant reductions in average CHC amounts consistent with CHCs of wild-caught flies. Overall, total hydrocarbon amounts increased from eclosion to 14-18 days, well past age at sexual maturity, and then declined in older flies. Most flies did not survive past 4 weeks. Baja California and mainland populations showed significantly different age-specific CHC profiles where Baja adults showed far less age-specific changes in CHC expression. Adults from populations reared on the host cactus typically used in nature expressed more CHCs than on the alternate host. MANCOVA with age as the covariate for the first six CHC principal components showed extensive differences in CHC composition due to age, population, cactus, sex, and age × population, age × sex, and age × cactus interactions. Thus, understanding variation in CHC composition as adult D. mojavensis age requires information about population and host plant differences, with potential influences on patterns of mate choice, sexual selection, and sexual isolation, and ultimately how these pheromones are expressed in natural populations. Studies of drosophilid aging in the wild are badly needed. PMID:25360246

  8. Abiotic factors shape microbial diversity in Sonoran Desert soils.

    Science.gov (United States)

    Andrew, David R; Fitak, Robert R; Munguia-Vega, Adrian; Racolta, Adriana; Martinson, Vincent G; Dontsova, Katerina

    2012-11-01

    High-throughput, culture-independent surveys of bacterial and archaeal communities in soil have illuminated the importance of both edaphic and biotic influences on microbial diversity, yet few studies compare the relative importance of these factors. Here, we employ multiplexed pyrosequencing of the 16S rRNA gene to examine soil- and cactus-associated rhizosphere microbial communities of the Sonoran Desert and the artificial desert biome of the Biosphere2 research facility. The results of our replicate sampling approach show that microbial communities are shaped primarily by soil characteristics associated with geographic locations, while rhizosphere associations are secondary factors. We found little difference between rhizosphere communities of the ecologically similar saguaro (Carnegiea gigantea) and cardón (Pachycereus pringlei) cacti. Both rhizosphere and soil communities were dominated by the disproportionately abundant Crenarchaeota class Thermoprotei, which comprised 18.7% of 183,320 total pyrosequencing reads from a comparatively small number (1,337 or 3.7%) of the 36,162 total operational taxonomic units (OTUs). OTUs common to both soil and rhizosphere samples comprised the bulk of raw sequence reads, suggesting that the shared community of soil and rhizosphere microbes constitute common and abundant taxa, particularly in the bacterial phyla Proteobacteria, Actinobacteria, Planctomycetes, Firmicutes, Bacteroidetes, Chloroflexi, and Acidobacteria. The vast majority of OTUs, however, were rare and unique to either soil or rhizosphere communities and differed among locations dozens of kilometers apart. Several soil properties, particularly soil pH and carbon content, were significantly correlated with community diversity measurements. Our results highlight the importance of culture-independent approaches in surveying microbial communities of extreme environments. PMID:22885757

  9. The Knee: Theory and Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Yodh, Gaurang B [University of California Irvine, Irvine, CA (United States)

    2006-10-15

    A review of current status of theoretical paradigm and results of direct and indirect experiments to study cosmic rays through the knee region are presented and discussed. There is general agreement that the knee is around a PeV and that it reflects a rigidity cutoff. The composition of cosmic rays in the knee region is mixed and changing with energy. The two direct experiments, JACEE and RUNJOB with measurements in the 100 TeV per particle to 1000 TeV per particle and with similar exposures do not agree. While JACEE indicates a increase in (lnA) from its low energy value of 1.5 to a value closer to 3 , the RUNJOB experiment sees no change in the composition albeit with large uncertainty. Of the indirect experiments, KASKADE, SPASEAMANDA, HEGRA-Airobic, CACTI, TUNKA and Tibet favor ''Heavy'' composition above the knee and beyond. The KASKADE energy range extends to 100 PeV where their analysis indicates iron dominance. KASKADE does not see a proton rigidity cutoff until about 3 PeV, while Tibet measures a steepening of the proton slope at a few hundred TeV. BLANCA and DICE favor little composition change or a change towards a proton dominated composition around 10 PeV. We need experiments with much better mass resolution in the energy range of the knee and a more quantitative understanding of the hadron production in the forward region at these energies to make definitive progress.

  10. From Fireproof Desert to Flammable Grassland: Buffelgrass Invasion in the Sonoran Desert

    Science.gov (United States)

    Betancourt, J. L.

    2007-12-01

    Only a few decades ago, the Sonoran Desert of northwestern Mexico and southern Arizona was considered mostly fireproof, a case of not enough fine fuel to connect the dominant shrubs and cacti. This has changed with invasions by non-native, winter annual and summer-flower perennial grasses that are rapidly transforming fireproof desert into flammable grassland. Of particular concern is buffelgrass, Pennisetum ciliare, a fire-prone and invasive African perennial grass that has already converted millions of hectares across Sonora since the mid-1960s and has made quick headway in southern and central Arizona beginning in the 1980s. Near Tucson and Phoenix, AZ, buffelgrass invasion is proceeding exponentially, with population expansion (and the costs of mitigation) more than doubling every year. As this conversion progresses, there will be increased fire risks, lost tourist revenue, diminished property values, insurmountable setbacks to conservation efforts, and the threat of large ignition fronts in desert valleys routinely spreading into the mountains. Although somewhat belated, an integrated, multi-jurisdictional effort is being organized to reduce ecological and economic impacts. My presentation will summarize the history and context of buffelgrass introduction and invasion, the disconnect in attitudes and policies across state and international boundaries, ongoing management efforts, the role of science and responsibilities of scientists, accelerated spread with changing climate, and impacts to regional ecosystems and economies. This narrative may serve as a template for other semi-arid lands where buffelgrass and similar grasses have become invasive, including Australia, South America, and many islands in the Pacific Ocean (including Hawaii), Indian Ocean, and Caribbean Sea.

  11. Differences in tolerance to host cactus alkaloids in Drosophila koepferae and D. buzzatii.

    Science.gov (United States)

    Soto, Ignacio M; Carreira, Valeria P; Corio, Cristian; Padró, Julián; Soto, Eduardo M; Hasson, Esteban

    2014-01-01

    The evolution of cactophily in the genus Drosophila was a major ecological transition involving over a hundred species in the Americas that acquired the capacity to cope with a variety of toxic metabolites evolved as feeding deterrents in Cactaceae. D. buzzatii and D. koepferae are sibling cactophilic species in the D. repleta group. The former is mainly associated with the relatively toxic-free habitat offered by prickly pears (Opuntia sulphurea) and the latter has evolved the ability to use columnar cacti of the genera Trichocereus and Cereus that contain an array of alkaloid secondary compounds. We assessed the effects of cactus alkaloids on fitness-related traits and evaluated the ability of D. buzzatii and D. koepferae to exploit an artificial novel toxic host. Larvae of both species were raised in laboratory culture media to which we added increasing doses of an alkaloid fraction extracted from the columnar cactus T. terschekii. In addition, we evaluated performance on an artificial novel host by rearing larvae in a seminatural medium that combined the nutritional quality of O. sulphurea plus amounts of alkaloids found in fresh T. terschekii. Performance scores in each rearing treatment were calculated using an index that took into account viability, developmental time, and adult body size. Only D. buzzatii suffered the effects of increasing doses of alkaloids and the artificial host impaired viability in D. koepferae, but did not affect performance in D. buzzatii. These results provide the first direct evidence that alkaloids are key determinants of host plant use in these species. However, the results regarding the artificial novel host suggest that the effects of alkaloids on performance are not straightforward as D. koepferae was heavily affected. We discuss these results in the light of patterns of host plan evolution in the Drosophila repleta group. PMID:24520377

  12. Primera cita de Scopaeothrips bicolor (Thysanoptera: Phlaeothripidae para América del Sur, con las descripciones de una nueva forma áptera y de la larva II First record of Scopaeothrips bicolor (Thysanoptera: Phlaeothripidae from South America, with descriptions of a new apterous form and the larva II

    Directory of Open Access Journals (Sweden)

    María I. Zamar

    2006-07-01

    Full Text Available El género Scopaeothrips Hood, 1912 incluye dos especies : S. unicolor Hood, 1912 y S. bicolor (Hood, 1912. Hasta el presente, S. bicolor fue citada para México, Texas, California y Arizona. Considerada como una especie dañina para cultivos de Opuntia Mill. fue descripta sobre la base de hembras macrópteras y braquípteras y machos braquípteros. En este estudio se describen las formas ápteras y la larva II. Los ejemplares fueron colectados en flores de Opuntia soehrensii Britton & Rose (cactácea silvestre de localidades ubicadas entre los 2049 m snm y 2849 m snm, en la provincia de Jujuy. Este estudio constituye la primera cita de S. bicolor para América del Sur, y define la variación del desarrollo de las alas como aporte importante para la diagnosis del género.The genus Scopaeothrips Hood, 1912 includes two species, S. unicolor Hood, 1912 and S. bicolor (Hood, 1912. To date, S. bicolor has been only recorded from Mexico , Texas , California , and Arizona . It has been regarded as a damaging species to Opuntia Mill. crops and described on the basis of macropterous and brachypterous female and brachypterous male specimens. The present study describes the apterous forms and larva II of this species. Specimens were collected on flowers of Opuntia soehrensii Britton & Rose (wild cacti in locations situated between 2049 m asl and 2849 m asl, in Jujuy province. The present study constitutes the first record of S. bicolor for South America and it defines the variation in the development of wings as an important contribution to the generic diagnosis.

  13. Use of alternative plant resources by common marmosets (Callithrix jacchus) in the semi-arid caatinga scrub forests of northeastern Brazil.

    Science.gov (United States)

    Amora, Tacyana Duarte; Beltrão-Mendes, Raone; Ferrari, Stephen F

    2013-04-01

    The common marmoset (Callithrix jacchus) is amply distributed in the Brazilian Northeast, but little is known of its ecology in the semi-arid Caatinga scrublands. The present study provides the first detailed data on the composition of the diet of C. jacchus in Caatinga ecosystems, derived from observations at four sites in the state of Sergipe. While exudate sources were gouged at all four sites in a manner typical of the species, fruit was the principal component of the diet at the main study site during most months, and a number of unusual items were eaten, including leaves, and the reproductive parts of cacti and bromeliads. These plants are rarely recorded in marmoset diets, but are common in caatinga habitats. Leaves were ingested during 5 of the 8 months monitored at the main study site, reaching 39.74% of the diet in 1 month, and appeared to be an alternative fallback food to plant exudates during periods when fruit was scarce. Three species of cactus provided both flowers and fruits, while the terrestrial bromeliad, Encholirium spectabile, provided nectar (30.81% of the diet in November). Approximately half of the plant species (and three families) identified in this study had not been recorded previously in the diet of Callithrix. Overall, the data suggest that, while the marmosets exploit the same types of plant foods in the Caatinga, the resource base is quite distinct from that of the Atlantic Forest. Other differences, such as relatively small groups and large home ranges, may contribute to divergent ecological patterns, which require more systematic investigation. Am. J. Primatol. 75:333-341, 2013. © 2012 Wiley Periodicals, Inc. PMID:23238956

  14. A review and evaluation of stemflow literature in the hydrologic and biogeochemical cycles of forested and agricultural ecosystems

    Science.gov (United States)

    Levia, Delphis F.; Frost, Ethan E.

    2003-04-01

    Stemflow is a spatially localized point input of precipitation and solutes at the plant stem and is of hydrological and ecological significance in forested and agricultural ecosystems. The purpose of this review is to: (1) critically evaluate our current understanding of stemflow; (2) identify gaps in our present knowledge of stemflow; and (3) stimulate further research in areas where present knowledge is weak. The review begins by analyzing stemflow drainage and nutrient inputs under diverse vegetal cover. Stemflow inputs are then examined as a function of meteorological conditions, seasonality, interspecific and intraspecific differences among and within species, canopy structure, spatiality, and atmospheric pollutants in urban environments. Stemflow modeling studies are also reviewed and evaluated. Stemflow yield and chemistry are the result of the interaction of the many complex variables listed. By analyzing each separately, it may be possible to isolate their individual affects on stemflow production and chemistry. A comprehensive understanding of each influencing factor would enable the accurate modeling of stemflow water and nutrient inputs into agricultural and forest soils which may result in the optimization of timber and crop harvests. Some areas where present knowledge is particularly weak are: (1) stemflow production and nutrient transfers in northern boreal forests (aspen, birch, conifers) and desert cacti; (2) chemical enrichment of stemflow from live trees charred by forest fires; (3) stemflow yield and nutrient inputs during the winter season; (4) intraspecific variation in stemflow production and chemistry; (5) stemflow chemistry from standing dead trees; (6) influence of canopy structure on stemflow chemistry; (7) understory stemflow generation and nutrient transfer; and (8) stemflow enrichment associated with insect infestations.

  15. Genomics of ecological adaptation in cactophilic Drosophila.

    Science.gov (United States)

    Guillén, Yolanda; Rius, Núria; Delprat, Alejandra; Williford, Anna; Muyas, Francesc; Puig, Marta; Casillas, Sònia; Ràmia, Miquel; Egea, Raquel; Negre, Barbara; Mir, Gisela; Camps, Jordi; Moncunill, Valentí; Ruiz-Ruano, Francisco J; Cabrero, Josefa; de Lima, Leonardo G; Dias, Guilherme B; Ruiz, Jeronimo C; Kapusta, Aurélie; Garcia-Mas, Jordi; Gut, Marta; Gut, Ivo G; Torrents, David; Camacho, Juan P; Kuhn, Gustavo C S; Feschotte, Cédric; Clark, Andrew G; Betrán, Esther; Barbadilla, Antonio; Ruiz, Alfredo

    2015-01-01

    Cactophilic Drosophila species provide a valuable model to study gene-environment interactions and ecological adaptation. Drosophila buzzatii and Drosophila mojavensis are two cactophilic species that belong to the repleta group, but have very different geographical distributions and primary host plants. To investigate the genomic basis of ecological adaptation, we sequenced the genome and developmental transcriptome of D. buzzatii and compared its gene content with that of D. mojavensis and two other noncactophilic Drosophila species in the same subgenus. The newly sequenced D. buzzatii genome (161.5 Mb) comprises 826 scaffolds (>3 kb) and contains 13,657 annotated protein-coding genes. Using RNA sequencing data of five life-stages we found expression of 15,026 genes, 80% protein-coding genes, and 20% noncoding RNA genes. In total, we detected 1,294 genes putatively under positive selection. Interestingly, among genes under positive selection in the D. mojavensis lineage, there is an excess of genes involved in metabolism of heterocyclic compounds that are abundant in Stenocereus cacti and toxic to nonresident Drosophila species. We found 117 orphan genes in the shared D. buzzatii-D. mojavensis lineage. In addition, gene duplication analysis identified lineage-specific expanded families with functional annotations associated with proteolysis, zinc ion binding, chitin binding, sensory perception, ethanol tolerance, immunity, physiology, and reproduction. In summary, we identified genetic signatures of adaptation in the shared D. buzzatii-D. mojavensis lineage, and in the two separate D. buzzatii and D. mojavensis lineages. Many of the novel lineage-specific genomic features are promising candidates for explaining the adaptation of these species to their distinct ecological niches. PMID:25552534

  16. Diversity and antifungal activity of the endophytic fungi associated with the native medicinal cactus Opuntia humifusa (Cactaceae) from the United States.

    Science.gov (United States)

    Silva-Hughes, Alice F; Wedge, David E; Cantrell, Charles L; Carvalho, Camila R; Pan, Zhiqiang; Moraes, Rita M; Madoxx, Victor L; Rosa, Luiz H

    2015-06-01

    The endophytic fungal community associated with the native cactus Opuntia humifusa in the United States was investigated and its potential for providing antifungal compounds. A hundred-eight endophytic fungal isolates were obtained and identified by molecular methods into 17 different taxa of the genera Alternaria, Aureobasidium, Biscogniauxia, Cladosporium, Cryptococcus, Curvularia, Diaporthe, Epicoccum, Paraconiothyrium, Pestalotiopsis and Phoma. The most frequent species associated with O. humifusa were Alternaria sp. 3, Aureobasidium pullulans and Diaporthe sp. The fungal community of O. humifusa had a high richness and diversity; additionally, the species richness obtained indicates that the sample effort was enough to recover the diversity pattern obtained. Six extracts of endophytes showed antifungal properties and (1)H NMR analyses of the extracts of Alternaria sp. 5 Ohu 8B2, Alternaria sp. 3 Ohu 30A, Cladosporium funiculosum Ohu 17C1 and Paraconiothyrium sp. Ohu 17A indicated the presence of functional groups associated with unsaturated fatty-acid olefinic protons and fatty acid methylene and methyl protons. GC-FID analysis of these extracts confirmed the presence of a mixture of different fatty acids. The (1)H NMR analyses of Biscogniauxia mediterranea Ohu 19B extracts showed the presence of aromatic compounds. From the extract of B. mediterranea we isolated the compound 5-methylmellein that displayed moderate antifungal activity against the phytopathogenic fungi Phomopsis obscurans. Our results suggest that native medicinal cacti of the United States can live symbiotically with rich and diverse endophytic communities and may be a source of bioactive molecules, including those able to inhibit or control plant disease pathogens. PMID:25851725

  17. Wood chemical composition in species of Cactaceae: the relationship between lignification and stem morphology.

    Science.gov (United States)

    Reyes-Rivera, Jorge; Canché-Escamilla, Gonzalo; Soto-Hernández, Marcos; Terrazas, Teresa

    2015-01-01

    In Cactaceae, wood anatomy is related to stem morphology in terms of the conferred support. In species of cacti with dimorphic wood, a unique process occurs in which the cambium stops producing wide-band tracheids (WBTs) and produces fibers; this is associated with the aging of individuals and increases in size. Stem support and lignification have only been studied in fibrous tree-like species, and studies in species with WBTs or dimorphic wood are lacking. In this study, we approach this process with a chemical focus, emphasizing the role of wood lignification. We hypothesized that the degree of wood lignification in Cactaceae increases with height of the species and that its chemical composition varies with wood anatomy. To test this, we studied the chemical composition (cellulose, hemicellulose, and lignin content) in 13 species (2 WBTs wood, 3 dimorphic, and 8 fibrous) with contrasting growth forms. We also analyzed lignification in dimorphic and fibrous species to determine the chemical features of WBTs and fibers and their relationship with stem support. The lignin contents were characterized by Fourier transform infrared spectroscopy and high performance liquid chromatography. We found that 11 species have a higher percentage (>35%) of lignin in their wood than other angiosperms or gymnosperms. The lignin chemical composition in fibrous species is similar to that of other dicots, but it is markedly heterogeneous in non-fibrous species where WBTs are abundant. The lignification in WBTs is associated with the resistance to high water pressure within cells rather than the contribution to mechanical support. Dimorphic wood species are usually richer in syringyl lignin, and tree-like species with lignified rays have more guaiacyl lignin. The results suggest that wood anatomy and lignin distribution play an important role in the chemical composition of wood, and further research is needed at the cellular level. PMID:25880223

  18. Ultra-high-pressure liquid chromatography tandem mass spectrometry determination of hallucinogenic drugs in hair of psychedelic plants and mushrooms consumers.

    Science.gov (United States)

    Pichini, Simona; Marchei, Emilia; García-Algar, Oscar; Gomez, Arelis; Di Giovannandrea, Rita; Pacifici, Roberta

    2014-11-01

    A procedure based on ultra-high-pressure liquid chromatography tandem mass spectrometry has been developed for the determination of mescaline, N,N-dimethyltryptamine, psilocin, psilocybin, salvinorin A in hair of consumers of psychedelic vegetal material such peyote or trichocereus cacti, psilocybe mushrooms, Salvia divinorum or psychedelic beverage ayahuasca. After hair washing with methyl alcohol and diethyl ether and subsequent addition of mescaline-d9 and 3,4-methylenedioxypropylamphetamine as internal standards, hair samples were treated with 250μl VMA-T M3 reagent for 1h at 100°C. After cooling, 100μl M3 extract were diluted with 400μl water and a volume of 10μl was injected into chromatographic system. Chromatographic separation was achieved at ambient temperature using a reverse-phase column and a linear gradient elution with two solvents: 0.3% formic acid in acetonitrile and 5mM ammonium formate pH 3. The mass spectrometer was operated in positive ion mode, using multiple reaction monitoring via positive electrospray ionization. The method was linear from the limit of quantification (0.03-0.05ng/mg depending on analyte under investigation) to 10ng/mg hair, with an intra- and inter-assay imprecision and inaccuracy always less than 15% and an analytical recovery between 79.6% and 97.4%, depending on the considered analyte. Using the validated method, mescaline was found in concentration range of 0.08-0.13ng/mg in hair of peyote smokers, 3.2ng salvinorin A per mg hair were determined in hair from a S. divinorum smoker, 5.6ng N,N-dimethyltryptamine per mg hair from an ayahuasca user and finally 0.8ng psilocybin per ng hair of a psilocybe consumer. PMID:25171488

  19. Genetic variation amongst biotypes of Dactylopius tomentosus.

    Science.gov (United States)

    Mathenge, Catherine W; Riegler, Markus; Beattie, G Andrew C; Spooner-Hart, Robert N; Holford, Paul

    2015-03-01

    The tomentose cochineal scale insect, Dactylopius tomentosus (Lamarck) (Hemiptera: Dactylopiidae), is an important biological control agent against invasive species of Cylindropuntia (Caryophyllales: Cactaceae). Recent studies have demonstrated that this scale is composed of host-affiliated biotypes with differential host specificity and fitness on particular host species. We investigated genetic variation and phylogenetic relationships among D. tomentosus biotypes and provenances to examine the possibility that genetic diversity may be related to their host-use pattern, and whether their phylogenetic relationships would give insights into taxonomic relatedness of their host plants. Nucleotide sequence comparison was accomplished using sequences of the mitochondrial cytochrome c oxidase I (COI) gene. Sequences of individuals from the same host plant within a region were identical and characterized by a unique haplotype. Individuals belonging to the same biotype but from different regions had similar haplotypes. However, haplotypes were not shared between different biotypes. Phylogenetic analysis grouped the monophyletic D. tomentosus into 3 well-resolved clades of biotypes. The phylogenetic relationships and clustering of biotypes corresponded with known taxonomic relatedness of their hosts. Two biotypes, Fulgida and Mamillata, tested positive for Wolbachia (α-Proteobacteria), a common endosymbiont of insects. The Wolbachia sequences were serendipitously detected by using insect-specific COI DNA barcoding primers and are most similar to Wolbachia Supergroup F strains. This study is the first molecular characterization of cochineal biotypes that, together with Wolbachia sequences, contribute to the better identification of the biotypes of cochineal insects and to the biological control of cacti using host-specific biotypes of the scale. PMID:24619863

  20. Wood chemical composition in species of Cactaceae: the relationship between lignification and stem morphology.

    Directory of Open Access Journals (Sweden)

    Jorge Reyes-Rivera

    Full Text Available In Cactaceae, wood anatomy is related to stem morphology in terms of the conferred support. In species of cacti with dimorphic wood, a unique process occurs in which the cambium stops producing wide-band tracheids (WBTs and produces fibers; this is associated with the aging of individuals and increases in size. Stem support and lignification have only been studied in fibrous tree-like species, and studies in species with WBTs or dimorphic wood are lacking. In this study, we approach this process with a chemical focus, emphasizing the role of wood lignification. We hypothesized that the degree of wood lignification in Cactaceae increases with height of the species and that its chemical composition varies with wood anatomy. To test this, we studied the chemical composition (cellulose, hemicellulose, and lignin content in 13 species (2 WBTs wood, 3 dimorphic, and 8 fibrous with contrasting growth forms. We also analyzed lignification in dimorphic and fibrous species to determine the chemical features of WBTs and fibers and their relationship with stem support. The lignin contents were characterized by Fourier transform infrared spectroscopy and high performance liquid chromatography. We found that 11 species have a higher percentage (>35% of lignin in their wood than other angiosperms or gymnosperms. The lignin chemical composition in fibrous species is similar to that of other dicots, but it is markedly heterogeneous in non-fibrous species where WBTs are abundant. The lignification in WBTs is associated with the resistance to high water pressure within cells rather than the contribution to mechanical support. Dimorphic wood species are usually richer in syringyl lignin, and tree-like species with lignified rays have more guaiacyl lignin. The results suggest that wood anatomy and lignin distribution play an important role in the chemical composition of wood, and further research is needed at the cellular level.

  1. In Vitro Propagation of Three Moroccan Prickly Pear Cactus Opuntia and Plant Establishment in Soil

    Directory of Open Access Journals (Sweden)

    Aissam EL FINTI

    2013-02-01

    Full Text Available Opuntia is one of the most widespread cacti, primarily due to their edible fruit and vegetable mass used as feed. The high demand for young plants of Opuntia made it necessary to find a rapid method of multiplication of the cactus, the safest method consisting in vitro micropropagation of species belonging to this genus. With aim of large production of plant material, a propagation system of three important prickly pear cactus cultivar (Opuntia ficus-indica in Morocco was developed. Segments of healthy young cladode (containing one areole were cultivated in Murashige and Skoog medium (MS containing adenine sulfate (40 mg/1, monosodium phosphate (50 mg/l, sucrose (50 g/l, phytagel (0.3% and benzyladenine (BA at 22.2 μM, to start the process of micropropagation. In vitro-developed shoots from areoles were used as secondary explants to induce shoot development in the MS medium with 5 mg/l of BA. All of the three studied cultivars showed an important multiplication rate in this medium. ‘Sidi Ifni M’ (‘Moussa’ cultivar shows the greatest number of shoots followed by ‘Sidi Ifni A’ (‘Aissa’ and ‘Delahia’ 17.26, 14.12 and 12.13 respectively. Rooting of in vitro-generated shoots was achieved most efficiently on half-strength MS basal medium supplemented with 0.5 mg/l of indole-3-butyric acid (IBA or IAA. Rooting frequencies were in the range from 95 to 100% and the highest mean number of root (19.1 was obtained with IBA for ‘Delahia’ cultivar. All micropropagated plants were transferred to greenhouse and all of them survived acclimatization process and showed good overall growth.

  2. Isotopic niche variation in a higher trophic level ectotherm: highlighting the role of succulent plants in desert food webs.

    Science.gov (United States)

    Delibes, Miguel; Blazquez, Ma Carmen; Fedriani, Jose Maria; Granados, Arsenio; Soriano, Laura; Delgado, Antonio

    2015-01-01

    Stable isotope analysis of animal tissues allows description of isotopic niches, whose axes in an n-dimensional space are the isotopic ratios, compared to a standard, of different isotope systems (e.g. δ(13)C, δ(15)N). Isotopic niches are informative about where an animal, population or species lives and about what it consumes. Here we describe inter- and intrapopulation isotopic niche (bidimensional δ(13)C-δ(15)N space) of the Orange-throated whiptail (Aspidoscelis hyperythra), an arthropodivorous small lizard, in ten localities of Baja California Sur (Mexico). These localities range from extreme arid to subtropical conditions. Between 13 and 20 individuals were sampled at each locality and 1 cm of tail-tip was collected for isotope analysis. As expected, interpopulation niche width variation was much larger than intrapopulation one. Besides, isotopic variation was not related to age, sex or individual size of lizards. This suggests geographic variation of the isotopic niche was related to changes in the basal resources that fuel the trophic web at each locality. The position of Bayesian isotope ellipses in the δ-space indicated that whiptails in more arid localities were enriched in 13C, suggesting most of the carbon they ingested came from CAM succulent plants (cacti, agaves) and in minor degree in C4 grasses. Contrarily, whiptails in subtropical areas were depleted in 13C, as they received more carbon from C3 scrubs and trees. Localities closer to sea-level tended to be enriched in 15N, but a clear influence of marine subsidies was detected only at individual level. The study contributes to identify the origin and pathways through which energy flows across the trophic webs of North American deserts. PMID:25973609

  3. Occurrence and identification of the etiologic agents of plant diseases in cactus (Opuntia ficus-indica Mill. in the semi-arid region of Paraiba

    Directory of Open Access Journals (Sweden)

    Anne Evelyne Franco de Souza

    2010-09-01

    Full Text Available Cactus forage (Opuntia ficus-indica Mill., intensely cultivated in dry regions of northeast Brazil, although well adapted to the harsh semi-arid climate is affected by major problems such as pests and diseases, responsible for significant losses in production. This study aimed to investigate the occurrence and diversity of the etiologic agents of diseases of cactus cultivated in 38 municipalities in the semi-arid region of Paraiba. The analyses were conducted and processed at the Laboratory of Phytopathology of the Centro de Ciências Agrárias da Universidade Federal da Paraíba, in Areia – PB. Starting from sick cladodes isolations, multiplications and identifications of the found microorganisms were made. The identification of the microorganisms was achieved through observations of the macro and micromorphological characteristics of the cultures and tests of Gram and pathogenicity. Great incidence and diversity of microorganisms was verified in the cacti researched, but the highest occurrence was mainly that of fungus. The fungi of widest occurrence were: Scytallidium lignicola, Alternate tenuis, Macrophomina phaseolina, Cladosporium cladosporides, Lasiodiplodia theobromae, Fusarium oxysporum f. sp. opuntiarum, Curvularia lunata, Aspergillus niger, Nigrospora sphaerica, Colletotrichum gloeosporioides, Exserohilum turcicum, Pestalotia pitospora, Rhizopus stolonifer, Rhizoctonia solani and Sphaceloma protearum. A bacterium was also detected that was suspected to belong to the Erwinia sp. strain. Satisfaction of the Postulates of Koch proved the infectious nature of the detected microorganisms. High occurrence of the fungus S. lignicola, an agent of scale rot disease in 100% of the places researched, was observed. This fact is of great concern, since the progression of the disease can cause significant losses in production.

  4. Survey and detection strategies for area-wide control of Cactoblastis cactorum

    International Nuclear Information System (INIS)

    Full text: Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) is renowned for its control of invasive cacti (Opuntia spp.), but survey techniques were limited to visual surveys of egg sticks and damaged cactus cladodes. With this insect's accidental arrival in Florida and its rapidly expanding range along the Gulf coast, research was conducted to develop improved survey and detection tactics in order to delineate the rate of spread of this invasive species, identify new outbreak infestations, and support control strategies. Virgin female-baited sticky traps were effective in detecting C. cactorum adult males, even in areas where visual surveys failed to detect larval damage. However, because the use of fertile females in traps placed beyond the currently infested area may result in an escaped fertile female that could establish a breeding population and expand the infested area, we compared the attractiveness and the longevity of fertile and irradiated (sterile) females deployed as bait in traps. Traps baited with females sterilised with gamma radiation were as effective as traps baited with unirradiated (fertile) females in detecting populations of feral C. cactorum male moths. Additional experiments have been conducted to evaluate different trap types, trap placement heights, and trap colors, as well as the age and number of female 'baits' for their ability to capture wild male cactus moths. Currently, studies are being conducted to identify the sex pheromone of C. cactorum females to use as bait in the most effective trap design. As a result of these preliminary studies, experimental synthetic lures have been identified and evaluated in laboratory bioassays and field trials. Preliminary data from these trials indicate that the lures are attractive to C. cactorum males and may be useful as a survey tool in an expanded trapping and detection network for C. cactorum. (author)

  5. Condensation on slippery asymmetric bumps

    Science.gov (United States)

    Park, Kyoo-Chul; Kim, Philseok; Grinthal, Alison; He, Neil; Fox, David; Weaver, James C.; Aizenberg, Joanna

    2016-03-01

    Controlling dropwise condensation is fundamental to water-harvesting systems, desalination, thermal power generation, air conditioning, distillation towers, and numerous other applications. For any of these, it is essential to design surfaces that enable droplets to grow rapidly and to be shed as quickly as possible. However, approaches based on microscale, nanoscale or molecular-scale textures suffer from intrinsic trade-offs that make it difficult to optimize both growth and transport at once. Here we present a conceptually different design approach—based on principles derived from Namib desert beetles, cacti, and pitcher plants—that synergistically combines these aspects of condensation and substantially outperforms other synthetic surfaces. Inspired by an unconventional interpretation of the role of the beetle’s bumpy surface geometry in promoting condensation, and using theoretical modelling, we show how to maximize vapour diffusion fluxat the apex of convex millimetric bumps by optimizing the radius of curvature and cross-sectional shape. Integrating this apex geometry with a widening slope, analogous to cactus spines, directly couples facilitated droplet growth with fast directional transport, by creating a free-energy profile that drives the droplet down the slope before its growth rate can decrease. This coupling is further enhanced by a slippery, pitcher-plant-inspired nanocoating that facilitates feedback between coalescence-driven growth and capillary-driven motion on the way down. Bumps that are rationally designed to integrate these mechanisms are able to grow and transport large droplets even against gravity and overcome the effect of an unfavourable temperature gradient. We further observe an unprecedented sixfold-higher exponent of growth rate, faster onset, higher steady-state turnover rate, and a greater volume of water collected compared to other surfaces. We envision that this fundamental understanding and rational design strategy can be

  6. Isotopic niche variation in a higher trophic level ectotherm: highlighting the role of succulent plants in desert food webs.

    Directory of Open Access Journals (Sweden)

    Miguel Delibes

    Full Text Available Stable isotope analysis of animal tissues allows description of isotopic niches, whose axes in an n-dimensional space are the isotopic ratios, compared to a standard, of different isotope systems (e.g. δ(13C, δ(15N. Isotopic niches are informative about where an animal, population or species lives and about what it consumes. Here we describe inter- and intrapopulation isotopic niche (bidimensional δ(13C-δ(15N space of the Orange-throated whiptail (Aspidoscelis hyperythra, an arthropodivorous small lizard, in ten localities of Baja California Sur (Mexico. These localities range from extreme arid to subtropical conditions. Between 13 and 20 individuals were sampled at each locality and 1 cm of tail-tip was collected for isotope analysis. As expected, interpopulation niche width variation was much larger than intrapopulation one. Besides, isotopic variation was not related to age, sex or individual size of lizards. This suggests geographic variation of the isotopic niche was related to changes in the basal resources that fuel the trophic web at each locality. The position of Bayesian isotope ellipses in the δ-space indicated that whiptails in more arid localities were enriched in 13C, suggesting most of the carbon they ingested came from CAM succulent plants (cacti, agaves and in minor degree in C4 grasses. Contrarily, whiptails in subtropical areas were depleted in 13C, as they received more carbon from C3 scrubs and trees. Localities closer to sea-level tended to be enriched in 15N, but a clear influence of marine subsidies was detected only at individual level. The study contributes to identify the origin and pathways through which energy flows across the trophic webs of North American deserts.

  7. Medicinal agents in the metabolic syndrome.

    Science.gov (United States)

    Baños, G; Pérez-Torres, I; El Hafidi, M

    2008-10-01

    The metabolic syndrome (MS) has become a worldwide health problem. It is difficult for patients to follow a diet/exercise regime that would improve their symptoms, therefore the investigation of agents that may deal with its more serious aspects is an important medical field for research. The cardiovascular consequences associated with the syndrome and some of the therapeutic approaches are discussed. The different agents can be divided into several groups: Inorganic/ organic: Zinc complexes with garlic components as insulino-mimetics; Selenium as antioxidant; Copper, Zinc and Manganese as microcomponents of antioxidant enzymes. Organic: Natural or Synthetic: Glycine is effective in lowering blood pressure, TBARS, intra-abdominal fat tissue and triglycerides in sucrose-fed rats. Pharmaceutical products: Fibrates, Lipid-lowering drugs. Antidiabetics. Anti-gout agents. On the other hand there are natural products such as those of animal origin: Sex hormones (also synthetic) used in the problems of menopause and hypoandrogenism frequently found in the MS, antioxidant Omega-3-oils (fish oils) or Vegetal: for example Digitalis pupurea, century-old cardiovascular medication as well as Magnolia officinalis; Spirulina maxima with beneficial effects as antioxidant and lipid-lowering agent, among others. Prickly Pear Cacti. (Opuntia Ficus- Indica Cochlospermum vitifolium (Willd.) Spreng) whose many properties against diabetes and hypercholesterolemia have been empirically known for many years. Perezone (from Perezia plants, a.k.a. Peonia) described as an antiplatelet aggregating agent. The mixed elements in the Mediterranean diet: Fish, salads (peppers, tomatoes), olive oil, garlic, red wine which combines fish oils, garlic and avocado as well as antioxidants from the rest of its components. PMID:18855636

  8. Life-history traits predict perennial species response to fire in a desert ecosystem.

    Science.gov (United States)

    Shryock, Daniel F; DeFalco, Lesley A; Esque, Todd C

    2014-08-01

    The Mojave Desert of North America has become fire-prone in recent decades due to invasive annual grasses that fuel wildfires following years of high rainfall. Perennial species are poorly adapted to fire in this system, and post-fire shifts in species composition have been substantial but variable across community types. To generalize across a range of conditions, we investigated whether simple life-history traits could predict how species responded to fire. Further, we classified species into plant functional types (PFTs) based on combinations of life-history traits and evaluated whether these groups exhibited a consistent fire-response. Six life-history traits varied significantly between burned and unburned areas in short (up to 4 years) or long-term (up to 52 years) post-fire datasets, including growth form, lifespan, seed size, seed dispersal, height, and leaf longevity. Forbs and grasses consistently increased in abundance after fire, while cacti were reduced and woody species exhibited a variable response. Woody species were classified into three PFTs based on combinations of life-history traits. Species in Group 1 increased in abundance after fire and were characterized by short lifespans, small, wind-dispersed seeds, low height, and deciduous leaves. Species in Group 2 were reduced by fire and distinguished from Group 1 by longer lifespans and evergreen leaves. Group 3 species, which also decreased after fire, were characterized by long lifespans, large non-wind dispersed seeds, and taller heights. Our results show that PFTs based on life-history traits can reliably predict the responses of most species to fire in the Mojave Desert. Dominant, long-lived species of this region possess a combination of traits limiting their ability to recover, presenting a clear example of how a novel disturbance regime may shift selective environmental pressures to favor alternative life-history strategies. PMID:25247062

  9. Historia natural cuantitativa de una relación parásito-hospedero: el sistema Tristerix-cactáceas en Chile semiárido Quantitative natural history of a host-parasite relationship: the Tristerix-cactus system in semiarid Chile

    Directory of Open Access Journals (Sweden)

    RODRIGO MEDEL

    2002-03-01

    Full Text Available Presentamos información cuantitativa de la historia natural de la relación parásito-hospedero constituida por el muérdago holoparásito Tristerix aphyllus (Loranthaceae y sus hospederos cactáceas. Más específicamente, indagamos en los determinantes históricos y biogeográficos de la interacción y cuantificamos la autoecología de la biología floral, polinización, dispersión y parasitismo en este sistema. El impacto del parasitismo sobre la evolución de sistemas defensivos en las cactáceas hospederas es considerado tanto a nivel intraespecífico como interespecífico, tomando en cuenta el potencial para selección mediada por parásitos y la estructura geográfica de la interacción. Finalmente, sugerimos futuras avenidas de investigación en este sistema que incluyen los tópicos de: (i evolución de la virulencia, (ii estructuración de la interacción en mosaico geográfico y, (iii pruebas históricas de adaptación. Estos aspectos permitirán adquirir un mayor conocimiento de la sutileza ecológica y de la evolución de esta especial interacción en los sistemas naturales de Chile semiáridoWe present quantitative information on the natural history of a host-parasite interaction that consists on the holoparasitic mistletoe Tristerix aphyllus (Loranthaceae and its cacti host species. More specifically, we inquire into the historical and biogeographical setting of the relationship, and quantify the autoecology of the floral biology, pollination, seed dispersal, and parasitism of the system. The impact of the mistletoe on the evolution of defense systems is evaluated both at intraspecific and interspecific levels through consideration of the potential for parasite-mediated selection and the geographical structure of the host-parasite interaction. Finally, we suggest prospective lines of research which include aspects related to: (i the evolution of virulence, (ii the geographic structure of the interaction, and (iii the historical

  10. Development of cell lines from the cactophagous insect: Cactoblastis cactorum (Lepidoptera: Pyralidae) and their susceptibility to three baculoviruses.

    Science.gov (United States)

    Grasela, James J; McIntosh, Arthur H; Ringbauer, Joseph; Goodman, Cynthia L; Carpenter, James E; Popham, Holly J R

    2012-05-01

    The unintentional introduction of the cactus moth, Cactoblastis cactorum, a successful biological control agent formerly employed in the control of invasive prickly pear cactus species (Opuntia spp.) in Australia, Hawaii, South Africa, and various Caribbean islands, has posed great concern as to the possible threat to native, endangered species of cactus in the southeastern USA as well as with the potential to cause a major infestation of commercial and agricultural cactus crops in Mexico. A number of control measures have been investigated with varying degrees of success including, field exploration for cactus moth-specific parasitoids, insecticides, fungal, bacterial, and nematode agents. Current tactics used by the USA-Mexico binational program to eradicate cactus moth from Mexico and mitigate its westward movement in the USA include host plant removal, the manual removal and destruction of egg sticks and infected cacti stems, and the Sterile Insect Technique. One other approach not taken until now is the development of a cactus moth cell line as a tool to facilitate the investigation of baculoviruses as an alternative biocontrol method for the cactus moth. Consequently, we established C. cactorum cell lines derived from adult ovarian tissue designated as BCIRL-Cc-AM and BCIRL-Cc-JG. The mean cell population doubling time was 204.3 and 112 h for BCIRL-Cc-AM and BCIRL-Cc-JG, respectively, with weekly medium change, while the doubling time was 176.6 and 192.6 h for BCIRL-Cc-AM and BCIRL-Cc-JG, respectively, with a daily change of medium. In addition, the daily versus weekly change in medium was reflected in the percentage viability with both cell lines showing higher levels with a daily medium change. Of the three baculoviruses tested, only the recombinant AcMNPV-hsp70Red and GmMNPV at a multiplicity of infection (MOI) of 1.0 were able to demonstrate significant production of extracellular virus (ECV) in each of the cell lines, whereas both cell lines were

  11. Metal-insulator transition caused by coupling to localized charge-frustrated systems under ice-rule local constraint

    Science.gov (United States)

    Ishizuka, Hiroaki; Udagawa, Masafumi; Motome, Yukitoshi

    2011-03-01

    We report the results of our theoretical and numerical study on electronic and transport properties of fermion systems with charge frustration. We consider an extended Falicov-Kimball model in which itinerant spinless fermions interact repulsively by U with localized particles whose distribution satisfies a local constraint under geometrical frustration, the so-called ice rule. Electronic states of the itinerant fermions are studied by approximating the statistical average by the arithmetic mean over different configurations of localized particles under the constraint. We numerically calculate the density of states, optical conductivity, and inverse participation ratio for models on the pyrochlore, checkerboard, and kagome lattices, and discuss the nature of metal-insulator transitions at commensurate fillings. The results are compared with exact solutions for models on Husimi cacti as well as with numerical results for completely random distributions of localized particles. As a result, we show that the ice-rule local constraint leads to several universal features in the electronic structure common to different lattice structures; a charge gap opens at a considerably small U compared to the bandwidth, and the energy spectrum approaches a characteristic form in the large-U limit, that is, the noninteracting tight-binding form in one dimension or a δ-functional peak. In the large-U region, the itinerant fermions are confined in the macroscopically degenerate ice-rule configurations, which consist of a bunch of one-dimensional loops: We call this insulating state the charge ice. On the other hand, transport properties are much affected by the geometry and dimensionality of the lattices; e.g., the pyrochlore lattice model exhibits a transition from a metallic to the charge-ice insulating state with increasing U, while the checkerboard lattice model appears to show Anderson localization before opening a gap. Meanwhile, in the kagome lattice case, we do not obtain

  12. In the Land of the Sky: Recent Paleoenvironmental Research From Coastal Oaxaca, Mexico

    Science.gov (United States)

    Goman, M. F.; Joyce, A. A.; Mueller, R. G.

    2005-05-01

    The Lower Río Verde Valley of Oaxaca has had a long and complex cultural history in part shaped by significant landscape change that ocurred 2300 years ago, when the Río Verde river changed morphology from a meandering to a braided form. These changes were precipitated by anthropogenic landuse impacts in the highland valleys of Oaxaca over 125 linear km to the north. While the lower valley's geomorphic history is well studied, little is known of its paleoecology. In order to reconstruct the history of vegetation, climate, and associated land use change, sediment cores were raised from several sites throughout the region. We present stratigraphical, palynological, and charcoal data from three sites in the region. The lower drainage basin consists entirely of the Verde's coastal valley. The climate of the lower Río Verde Valley is hot and humid with mean annual rainfall of 1000 mm to 2000 mm and average temperatures range from 25°C to 28°C. We discuss the pollen and stratigraphic record from Laguna Pastoría which is a brackish estuary protected from the Pacific Ocean by a roughly east-west trending bay barrier. The bay barrier is about 500 m wide and 2 to 4 m high. Low scrub vegetation (cacti, thorny bushes, small trees and palms) grow on the barrier. The lagoon itself is approximately 9 km long and varies in depth with a 3-4 m maximum. Tides are microtidal (1 m). The lagoon supports a diverse array of mangroves (Rhizophora mangle, Laguncularia racemosa, Conocarpus erectus and Avicennia germinans). Two sediment cores were raised from the lagoon (LP1 and LP2) and provide a record of hurricane strikes and possible changes in the frequency of El Niño's. The LP1 core covers approximately the last 5000 yrs. Preliminary pollen analysis indicates that pollen is in excellent condition and is diverse (>60 taxa). Zea mays pollen was identified from sediments dating to the early Formative period (~ 3600 yr ago). The charcoal records analyzed from 2 paleomeanders of the

  13. New solvent systems for gradient counter-current chromatography in separation of betanin and its derivatives from processed Beta vulgaris L. juice.

    Science.gov (United States)

    Spórna-Kucab, Aneta; Garrard, Ian; Ignatova, Svetlana; Wybraniec, Sławomir

    2015-02-01

    Betalains, natural plant pigments, are beneficial compounds due to their antioxidant and possible chemoprotective properties. A mixture of betalains: betanin/isobetanin, decarboxybetanins and neobetanin from processed red beet roots (Beta vulgaris L.) juice was separated in food-grade, gradient solvent systems using high-performance counter-current chromatography (HPCCC). The decarboxylated and dehydrogenated betanins were obtained by thermal degradation of betanin/isobetanin from processed B. vulgaris L. juice under mild conditions. Two solvent systems (differing in their composition by phosphoric acid and ethanol volume gradient) consisting of BuOH-EtOH-NaClsolution-H2O-H3PO4 (v/v/v/v/v, 1300:200-1000:1300:700:2.5-10) in the 'tail-to-head' mode were run. The flow rate of the mobile phase (organic phase) was 1.0 or 2.0 ml/min and the column rotation speed was 1,600 rpm (20°C). The retention of the solvent system stationary phase (aqueous phase) was ca. 80%. The system with the acid and ethanol volume gradient consisting of BuOH-EtOH-NaClsolution-H2O-H3PO4 (v/v/v/v/v, 1300:200-240:1300:700:2.5-4.5) pumped at 2.0 ml/min was the most effective for a separation of betanin/isobetanin, 17-decarboxy-betanin/-isobetanin, 2-decarboxy-betanin/-isobetanin, 2,17-bidecarboxy-betanin/-isobetanin pairs as well as neobetanin. The pigments were detected by LC-DAD and LC-MS. The results are crucial in the application of completely food-grade solvent systems in separation of food-grade compounds as well, and the systems can possibly be extended to other ionizable and polar compounds with potential health benefits. In particular, the method is applicable for the isolation and purification of betalains present in such rich sources as B. vulgaris L. roots as well as cacti fruits and Amaranthaceae flowering plants due to modification possibilities of the solvent systems polarity. PMID:25595533

  14. Regeneration of Carnegiea gigantea (Cactaceae) since 1850 in three populations in the northern Sonoran Desert

    Science.gov (United States)

    Drezner, Taly Dawn

    2006-03-01

    Saguaro cacti ( Carnegiea gigantea) are long-lived and exhibit great variability in growth that makes age estimation problematic. A few single-site studies have focused on those locales where long-term data (e.g. 85 years) are available. Using a newly developed technique, 733 saguaros were sampled in three locales (Silverbell, Harcuvar, Kofa) across Arizona and their age structure reconstructed for the last 150 years based on a mathematical model of the heights of individuals. This is the first study to compare regeneration at multiple locations across the species' range. Regression analysis for each site (years and frequency of individuals established during that year) was run and residuals extracted to determine peaks and troughs in regeneration over time. Correlation was run on the residuals between sites, and chi-square analysis was employed to compare frequency of good and bad regeneration years between Kofa and Silverbell. Peaks and troughs represent regeneration as well as survivorship and mortality. Several large cohorts established at Kofa and Harcuvar since 1850, while at Silverbell well over 80% of sampled saguaros established after the late 1930s. This more recent recruitment at Silverbell may be related to the major freezing event of 1937 whose impact was likely greater at the cooler Silverbell site. Despite the widely different population structures at Silverbell and Kofa, recruitment trends in both populations were statistically linked as both locales often benefited from the same favorable periods for regeneration ( P < 0.001). The Harcuvar population shares some common peaks and troughs in regeneration over time with Kofa and Silverbell, but its relationship to them is not statistically significant. Some trends overlap in some locales, such as the favorable regeneration period in the late 1800s and early 1900s, particularly at Silverbell and Kofa as well as at other known sites. However, each population has its own signature. Silverbell is a

  15. Micro-morphology and anatomy of Turbinicarpus (Cactaceae spines Micromorfología y anatomía de las espinas de Turbinicarpus (Cactaceae

    Directory of Open Access Journals (Sweden)

    Alessandro Mosco

    2009-04-01

    Full Text Available Spines are a striking feature of cacti and display wide variation in size, number, shape, and texture. This study showed that Turbinicarpus species exhibit not only a high variability in the gross morphology of the spines, but also in their micro-morphology. Their surface can be smooth or ornamented with projections that can be low, conical, pinnate, or long trichomes. The epidermis can be continuous, broken up into single cell elements or transversely fissured, the fissures extending deeply into the underlying sclerenchyma. The mechanical properties of the spines are related to their anatomy, here documented for the first time. The woody rigid spines being made up of fibers with thick walls (> 3 µm, while papery or corky spines have a sclerenchyma made up of fibers with thin walls (Las espinas son una de las características más distintivas de las cactáceas y se distinguen por su variación en tamaño, número, forma y textura. Este estudio muestra que las especies de Turbinicarpus no sólo tienen variación en la morfología de sus espinas, sino también en su micro-morfología. Su superficie puede ser lisa u ornamentada con proyecciones bajas, cónicas, pinadas o bien con tricomas largos. En las espinas, la epidermis se mantiene continua, separada en sus células o transversalmente fisurada. Las fisuras de la epidermis pueden prolongarse hasta el esclerénquima más interno. Las propiedades mecánicas de las espinas están relacionadas con su anatomía, aquí documentada por primera vez. Las espinas rígidas están constituidas de fibras con paredes gruesas (> 3 µm, mientras que las espinas suaves o corchosas, también denominadas cerdas tienen esclerénquima de fibras con paredes delgadas (< 2 µm. Además, algunas espinas en su madurez tienen 2 tipos de fibras, las pobremente lignificadas en la parte externa y en la interna las de paredes gruesas y lignificadas. La taxonomía de Turbinicarpus se basa principalmente en las espinas y los

  16. Morphology and anatomy of Rhipsalis cereuscula, Rhipsalis floccosa subsp. hohenauensis and Lepismium cruciforme (Cactaceae seedlings Morfología y anatomía de las plántulas de Rhipsalis cereuscula, Rhipsalis floccosa subsp. hohenauensis y Lepismium cruciforme (Cactaceae

    Directory of Open Access Journals (Sweden)

    Alan C. Secorun

    2011-03-01

    Full Text Available Rhipsalis cereuscula Haw., Rhipsalis floccosa subsp. hohenauensis (F. Ritter Barthlott et N. P. Taylor and Lepismium cruciforme (Vellozo Miquel are obligatory epiphytes that occur frequently on tree trunks of remnant forests in Maringa, Paraná state, Brazil. Morphological and anatomical analyses regarding the seedlings were carried out. The seedlings were prepared according to techniques of resin inclusions and histochemical tests. Seedlings were phanerocotyledonar and originated from seeds with operculum. The root was diarch and the hypocotyl presented transition root-stem structure. The cotyledons were sessile, reduced, with homogeneous mesophyll. The epicotyl (phylloclade presented a lot of parenchyma and reduced vascular cylinder. The 3 studied species showed anatomical characteristics similar to those described for species of Lepismium and Rhipsalis as well as other cacti.Rhipsalis cereuscula Haw., Rhipsalis floccosa subsp. hohenauensis (F. Ritter Barthlott et N. P. Taylor y Lepismium cruciforme (Vellozo Miquel son epífitos obligatorios que frecuentemente habitan en los troncos del árbol de matorrales secundarios de Maringá, Paraná, Brasil. Se analizaron la morfología y anatomía de las plántulas de estas especies. Las plántulas fueron procesadas según las técnicas de inclusión en resina y pruebas histoquímicas. Las plántulas se clasificaron como fanerocotiledonares y se originaron de semillas con opérculo. La raíz era diarca y el hipocótilo presentó estructura de transición raíz-tallo. Los cotiledones fueron sésiles, reducidos, con el mesófilo homogéneo. El epicótilo (filocladio presentó mucho parénquima y el cilindro vascular reducido. Las 3 especies presentaron características anatómicas similares a las descritas para especies de Lepismium y Rhipsalis, así como otras cactáceas.

  17. Temperature in the seeds germination of pitaya genotypes

    Directory of Open Access Journals (Sweden)

    Alessandro Borini Lone

    2014-09-01

    Full Text Available The optimum temperature for germination of cacti vary with the species. With this work, we aimed to evaluate the seeds germination of pitaya genotypes under different temperatures. The used genotypes were: Hylocereus undatus (PB, H. polyrhizus (PV, Selenicereus megalanthus (PA, H. undatus x H. costaricensis (PH1 and H. costaricensis x H. undatus (PH2. For each genotype we used four replicates of 50 seeds, in a completely randomized design. The sowing was carried out on blotter paper in boxes type Gerbox ®, maintained at temperatures of 15, 20, 25, 30 and 35 oC constant and 15-25, 20-30 and 25-35 oC alternating with photoperiod 12 hours. The test lasted 30 days which were appraised the germination percentage, the germination speed index and the average time of germination. For seeds germination of PB, the result obtained in the temperature of 25 oC didn’t differ of the obtained to 30 and 20-30 oC, however it was superior to the others temperatures. In PV, the result at 25 oC didn’t differ of the obtained to 20 and 30 oC, being superior to the results of the others temperatures. For PA, the best result was obtained to 25 oC. In PH1, the temperatures of 25, 30 and 20-30 oC presented superiors results to the others. For PH2, the result obtained in 15-25oC didn’t differ of the obtained at 25 oC, however it was superior to the others temperatures. The constants temperatures of 25 and 30 °C and alternating 20-30 °C are suitable for germination of H. undatus and for the hybrid H. undatus x H. costaricensis. For H. polyrhizus, constant temperatures of 20, 25 to 30 °C are suitable for seed germination. The constant temperature of 25 °C is the most suitable for the germination of S. megalanthus. For the hybrid H. costaricensis x H. undatus, constant temperature of 25 °C and alternating 15-25°C are suitable for seed germination.

  18. Empirical assessment of state-and-transition models with a long-term vegetation record from the Sonoran Desert.

    Science.gov (United States)

    Bagchi, Sumanta; Briske, David D; Wu, X B; McClaran, Mitchel P; Bestelmeyer, Brandon T; Fernández-Giménez, Maria E

    2012-03-01

    drivers require more attention in STMs. Many features of the expert models, including the number of communities and participant species, were consistent with empirical trends, but expert models underrepresented recent increases in cacti while overemphasizing the introduced Lehmann's lovegrass (Eragrostis lehmanniana). Quantification of communities and transitions within long-term vegetation records presents several quantitative metrics such as transition frequency, magnitude of accompanying compositional change, presence of unidirectional trajectories, and lack of reversibility within various timescales, which can clarify resilience concepts and inform the construction and interpretation of STMs. PMID:22611843

  19. Landscape management and domestication of Stenocereus pruinosus (Cactaceae in the Tehuacán Valley: human guided selection and gene flow

    Directory of Open Access Journals (Sweden)

    Parra Fabiola

    2012-08-01

    types and move propagules from one another. Multivariate analyses showed morphological differentiation of wild and agriculturally managed populations, mainly due to differences in reproductive characters; however, the phenotypic differentiation indexes were relatively low among all populations studied. Morphological diversity of S. pruinosus (average MD = 0.600 is higher than in other columnar cacti species previously analyzed. Conclusions Artificial selection in favor of high quality fruit promotes morphological variation and divergence because of the continual replacement of plant material propagated and introduction of propagules from other villages and regions. This process is counteracted by high gene flow influenced by natural factors (pollinators and seed dispersers but also by human management (movement of propagules among populations, all of which determines relatively low phenotypic differentiation among populations. Conservation of genetic resources of S. pruinosus should be based on the traditional forms of germplasm management by local people.

  20. Alto Patache fog oasis in the Atacama Desert: Geographical basis for a sustainable development program

    Science.gov (United States)

    Calderón, M.; Cereceda, P.; Larrain, H.; Osses, P.; Pérez, L.; Ibáñez, M.

    2010-07-01

    Alto Patache coastal fog oasis is a protected area located south of Iquique, Northern Chile, being presently in charge of the Atacama Desert Center (ADC) research group of the Pontificia Universidad Católica de Chile, since 1997. On 2007, the Chilean Government bestowed a piece of land stretch covering 1,114 hectares to ADC scientific group for scientific research, ecosystem protection and environmental education. This oasis has been recently studied from different points of view: climate, biogeography, fog collection, geomorphology, soil survey and land use planning, plant distribution, conservation and archaeology. During 2009, a study of the geographical basis to elaborate a general management plan was undertaken to collect information to fulfill our planned out objectives. Through this study, georreferenciated strategic information was compiled to evaluate future actions conducting to a sustainable development within the protected area. This information was translated into thematic maps showing the spatial distribution of variables like: climate, geology, geomorphology, soils, vegetation, fauna, archaeological sites and management zones. The methodology used is the analysis of satellite imagery, using GPS by creating a cartographic Data Base incorporated in GIS. Results show that the area starts at the littoral plain, ranging from 500 m to 2.000 m, being continued in parts by a piedmont intercepted by a very abrupt mega-cliff, or hectares of climbing sand dunes leading to a short high plateau limited by a soft hilly area to the East. Two soil types are characteristic: Entisols (Torriorthent) covering the coastal beach sediments, and Aridisols along the cliff and adjacent hills. Vegetation consists not only of a very rich lichen cover, but also of endangered vascular species associations constituting a very fragile sub-tropical coastal desert community, such as Eulychnia, Cumulopuntia, Eriosyce cacti, and Lycium - Nolana- Ephedra communities. Fog oasis

  1. TR-PIV measurement of the wake behind a grooved cylinder at low Reynolds number

    Science.gov (United States)

    Liu, Ying Zheng; Shi, Liu Liu; Yu, Jun

    2011-04-01

    A comparative study of the wakes behind cylinders with grooved and smooth surfaces was performed with a view to understand the wake characteristics associated with the adult Saguaro cacti. A low-speed recirculation water channel was established for the experiment; the Reynolds number, based on the free-stream velocity and cylinder diameter (D), was kept at ReD=1500. State-of-the-art time-resolved particle image velocimetry (TR-PIV) was employed to measure a total of 20 480 realizations of the wake field at a frame rate of 250 Hz, enabling a comprehensive view of the time- and phase-averaged wake pattern. In comparison to the wake behind the smooth cylinder, the length of the recirculation zone behind the grooved cylinder was extended by nearly 18.2%, yet the longitudinal velocity fluctuation intensity was considerably weakened. A global view of the peaked spectrum of the longitudinal velocity component revealed that the intermediate region for the grooved cylinder, which approximately corresponds to the transition region where the shear layer vortices interact, merge and shed before the formation of the Karman-like vortex street, was much wider than that for the smooth one. The unsteady events near St=0.3-0.4 were detected in the intermediate region behind the grooved cylinder, but no such events were found in the smooth cylinder system. Although the formation of the Karman-like vortex street was delayed by about 0.6D downstream for the grooved cylinder, no prominent difference in the vortex street region was found in the far wake for both cylinders. The Proper Orthogonal Decomposition (POD) method was used extensively to decompose the vector and swirling strength fields, which gave a close-up view of the vortices in the near wake. The first two POD modes of the swirling strength clarified the spatio-temporal characteristics of the shear layer vortices behind the grooved cylinder. The small-scale vortices superimposed on the shear layers behind the grooved cylinder

  2. Blooming rhythms of cactus Cereus peruvianus with nocturnal peak at full moon during seasons of prolonged daytime photoperiod.

    Science.gov (United States)

    Ben-Attia, Mossadok; Reinberg, Alain; Smolensky, Michael H; Gadacha, Wafa; Khedaier, Achraf; Sani, Mamane; Touitou, Yvan; Boughamni, Néziha Ghanem

    2016-01-01

    Cereus peruvianus (Peruvian apple cactus) is a large erect and thorny succulent cactus characterized by column-like (cereus [L]: column), that is, candle-shaped, appendages. For three successive years (1100 days), between early April and late November, we studied the flowering patterns of eight cacti growing in public gardens and rural areas of north and central Tunisia, far from nighttime artificial illumination, in relation to natural environmental light, temperature, relative humidity and precipitation parameters. Flower blooming was assessed nightly between 23:00 h and until at least 02:00 h, and additionally around-the-clock at ~1 h intervals for 30 consecutive days during the late summer of each year of study to quantify both nyctohemeral (day-night) and lunar patterns. During the summer months of prolonged daytime photoperiod, flower blooming of C. peruvianus exhibited predictable-in-time variation as "waves" with average period of 29.5 days synchronized by the light of the full moon. The large-sized flower (~16 cm diameter) opens almost exclusively at night, between sunset and sunrise, as a 24 h rhythm during a specific 3-4-day span of the lunar cycle (full moon), with a strong correlation between moon phase and number and proportion of flowers in bloom (ranging from r = +0.59 to +0.91). Black, blue and red cotton sheets were used to filter specific spectral bands of nighttime moonlight from illuminating randomly selected plant appendages as a means to test the hypothesis of a "gating" 24 h rhythm phenomenon of photoreceptors at the bud level. Relative to control conditions (no light filtering), black sheet covering inhibited flower bud induction by 87.5%, red sheet covering by 46.6% and blue sheet covering by 34%, and the respective inhibiting effects on number of flowers in bloom were essentially 100%, ~81% and ~44%. C. peruvianus is a unique example of a terrestrial plant that exhibits a circadian flowering rhythm (peak ~00:00 h) "gated" by 24 h, lunar

  3. Don't let cacto blast us: Development of a bi-national plan to stop the spread of the cactus moth, Cactoblastis cactorum, in North America

    International Nuclear Information System (INIS)

    Full text: Until its appearance in the United States (USA) as an invasive insect, the South American cactus moth, Cactoblastis cactorum (Berg), was considered the undisputed poster child for biological control of weeds because of its dramatic role in reducing expansive populations of unwanted prickly pear cacti in Australia and elsewhere around the world. Since its detection in south Florida in 1989, the cactus moth has expanded its range north along the Atlantic Coast as far as Bull Island near Charleston, South Carolina and west along the Gulf Coast as far as Dauphin Island, Alabama. Prickly pear cactus is of minor importance in the USA as a domestically produced food crop. However, prickly pear cactus has significant value as an ecological plant, adding to wildlife habitat, ecosystem structure and biodiversity in both developed and undeveloped areas. Additionally, further westward spread could lead into Mexico, where prickly-pear cactus is a major agricultural commodity and has significantly larger socio-economic importance. A meeting of assessment and planning was first held in Tampa, Florida in September 2000 with scientific experts, regulatory officials, and representatives from the conservation community from the USA, Mexico and South Africa. Meeting participants agreed that the cactus moth has the potential to be devastating to the fragile arid environments in the USA and Mexico. In July 2002, the FAO and IAEA hosted a cactus moth consultants meeting to review and evaluate the threat of C. cactorum to international agriculture and biodiversity. The role that the Sterile Insect Technique (SIT) could play in addressing the cactus moth invasion as a model for invasive pests affecting not only agriculture but the environment was assessed. Furthermore, FAO and IAEA agreed to support research in member states for development of the SIT. Subsequent stakeholder meetings have been held in Miami, Florida in December 2003 and Mexico City, Mexico in July 2004

  4. Factores que afectan la distribución circular del muérdago sin hojas Tristerix aphyllus (Loranthaceae sobre el cacto Echinopsis chilensis Factors affecting the circular distribution of the leafless mistletoe Tristerix aphyllus (Loranthaceae on the cactus Echinopsis chilensis

    Directory of Open Access Journals (Sweden)

    CAREZZA BOTTO-MAHAN

    2000-09-01

    observed circular distribution of the parasite inflorescence differed significantly from a uniform distribution based on a random process. We quantified the circular distribution of the seeds defecated on the cactus surface by Mimus thenca, the only bird responsible of seed dispersal. Our data did not support the idea of a directional seed deposition by the bird. To test the hypothesis that the observed circular distribution can be attributable to a differential seed survival due to microsite temperature variation, we infected cacti with seeds of T. aphyllus every 30ºand quantified the temperature associated to each angle. Our results revealed that even though seeds located in angles with higher sun exposure had the lowest haustorial disk formation, this variation in mortality is not sufficient to explain the angular polarity observed in this species. Inspection of inflorescences of T. aphyllus that emerged 17 months after the experimental infection, revealed mean angular values indistinguishable from the natural circular distribution. Assessment of the anatomical structure at two opposing angles of the cactus revealed striking differences in epidermal constitution, such as a four-fold thicker epidermis in north than in south facing samples due to formation of highly lignified bark. We suggest that bark formation is likely the most important factor determining the biased circular distribution of T. aphyllus

  5. Mixobiota do Parque Nacional Serra de Itabaiana, SE, Brasil: Trichiales Myxobiota of Serra de Itabaiana National Park, Sergipe, Brazil: Trichiales

    Directory of Open Access Journals (Sweden)

    Maria de Fátima de Andrade Bezerra

    2010-06-01

    with sandy soils, grasses, sedges, cacti, bromeliads and shrubs. Sporocarps were collected over a two-year period (19 field trips; dead wood, litter, bark and dung of Sylvilagus brasiliensis L. were collected for moist-chamber cultures (590. Ten species were identified: Arcyria cinerea (Bull. Pers., A. denudata (L. Wettst., A. obvellata (Oeder Onsberg, Hemitrichia calyculata (Speg. M. L. Farr, H. minor G. Lister, H. serpula (Scop. Rostaf. ex Lister, Metatrichia vesparia (Batsch Nann.-Bremek. ex G. W. Martin & Alexop., Perichaena chrysosperma (Curr. Lister, P. depressa Lib., and Trichia affinis de Bary. Trichiales were present in six microhabitats, and lignicolous and foliicolous species were predominant. Three fimicolous species were recorded: A. cinerea, H. minor and M. vesparia. The most constant and abundant species were A. cinerea, A. denudata, and H. calyculata, which were found at different altitudes (180-670 m. Descriptions are given for each species as well as their geographic distribution in Brazil. A. denudata, A. obvellata, H. calyculata, P. chrysosperma, and T. affinis are new records for Sergipe, raising to 58 the number of Myxomycetes species recorded for this state.

  6. Dispersão de sementes de Melocactus glaucescens e M. paucispinus (Cactaceae, no Município de Morro do Chapéu, Chapada Diamantina - BA Dispersion of Melocactus glaucescens and M. paucispinus (Cactaceae in the municipality of Morro do Chapéu, Chapada Diamantina - BA

    Directory of Open Access Journals (Sweden)

    Rosineide Braz Santos Fonseca

    2012-06-01

    lizard and three ant species were dispersers of the two species of Melocactus. Seed dormancy was not broken in the digestive tracts of the lizards. The greatest rates of fruit removal by the lizards occurred during the mid hours of the day, coinciding with or following the extrusion peak. Fruit emergence and extrusion rates were highest in the morning, increasing their chances of being taken on the same day, thus avoiding desiccation and predation. No correlation was observed between fruit liberation and thermal variations of the cephalium. Fruit development generates tension within the fiber mass of the cephalium that provokes fruit emergence/expulsion. The expulsion of the fruits may also be aided by the dilation of the cephalium fibers as they warm, tension generated at the cephalium base where the fibers unite, and by the expulsion of other fruits. The spatial distribution of these cacti is influenced by disperser behavior.

  7. Flora cactológica y especies asociadas en el área natural protegida Sierra Corral de los Bandidos, Nuevo León, México Cactus list and asociated plants of the protected natural area Sierra Corral de Los Bandidos, Nuevo Leon, Mexico

    Directory of Open Access Journals (Sweden)

    María del Pilar Carmona-Lara

    2008-12-01

    Full Text Available El área natural protegida (ANP Sierra Corral de los Bandidos ubicada en la sierra Madre Oriental, al noroeste de Monterrey, sufre el impacto de actividades antropológicas asociadas al matorral submontano (ganadería, agricultura, colecta y urbanismo, disminuyendo sus recursos naturales y amenazando sus especies endémicas, principalmente cactáceas. El propósito del estudio fue conocer la diversidad de cactáceas y especies asociadas en zonas de amortiguamiento y núcleo. Para ello se determinaron índices de riqueza y similitud utilizando un muestreo estratificado con cuadrantes a lo largo de transectos orientados por gradientes altitudinales según su zonificación. En total se registraron 112 taxa (30 cactáceas, 87 (24 cactáceas en zona de amortiguamiento y 80 (19 cactáceas en zona núcleo. Por su densidad, frecuencia y abundancia sobresalieron Echinocereus stramineus (Engelm. Engelm. ex F. Seitz, Cylindropuntia leptocaulis F. M. Knuth in Backeb et F. M. Knuth, Mammillaria melanocentra Poselg., Neolloydia conoidea (DC Britton et Rose, (Cactaceae; Erioneuron avenaceum (H. B et K. Tateoka, (Poaceae; Viguiera stenoloba S. F. Blake; Zexmenia hispida (Kunth A. Gray, (Asteraceae y Agave lechuguilla Torr, (Agavaceae. Existe diferencia significativa entre las poblaciones de cactus de las zonas del ANP, según Jacquard (13%, Sörensen (38% y Morisita (0.44. Ocho cactáceas (7 endémicas están registradas en algún estatus de la NOM-ECOL-059, 2001.The Sierra Corral de los Bandidos is a natural protected area located in the Sierra Madre Oriental mountain range northwest of Monterrey city. This preserve suffers the impact of human activities in the form of cattle ranching, agriculture, harvest of wild plants, and urbanism, diminishing its natural resources and threatening its endemic species, especially from the cactaceae family. The purpose of this study was to obtain information on the diversity of cacti and associated species in the buffer and

  8. Tissue localization of betacyanins in cactus stems Localización de betacianinas en tejido del tallo de cactus

    Directory of Open Access Journals (Sweden)

    Alessandro Mosco

    2012-06-01

    Full Text Available Betalains are soluble pigments found only in the suborder Chenopodiniae, while in all other Angiospermae they are replaced by anthocyanins. The convergent evolution of the presence of anthocyanins and betalains in vegetative tissues supports the hypothesis of a similar function, based on the absorption properties of these pigments. The screening effect of anthocyanins results in the reduction of the amount of photoinhibition. betalains, being the anthocyanin counterpart in most families of Caryophyllales, were also suggested to have a screening role. This study is aimed at identifying in which Cactaceae stem tissues betacyanins, reddish to violet betalain pigments, accumulate. Stem accumulation of betacyanins was observed in cacti both in their natural habitat and in cultivation. The localization of betacyanins was assessed by light microscope studies on tubercle transverse sections. During 2 field trips in distinct years to the Mexican plateau in March, many cactus species, belonging to different genera, were observed displaying a reddish stem. Light microscope studies on cultivated plants showed that betacyanins accumulate in the hypodermis and in the outer layers of the chlorenchyma, where they may act as a screen, thus protecting the photosystems present in the underlying chlorenchyma, and have a possible antioxidant function in the cortex.Las betalaínas son pigmentos solubles que se encuentran sólo en el suborden Chenopodiniae, mientras que en el resto de Angiospermae, lo que existe son antocianinas. La evolución convergente de la presencia de antocianinas y betalaínas en tejidos vegetativos apoya la hipótesis de una función similar, que se basa en las propiedades de absorción de estos pigmentos. El efecto pantalla de las antocianinas resulta en la reducción de fotoinhibición. Siendo las betalaínas la contraparte antocianítica en la mayoría de las familias de Caryophyllales, se sugirió también un papel de pantalla de estos

  9. Bio-cultural anchorage of the prickly pear cactus in Tlalnepantla (Morelos, Mexico

    Directory of Open Access Journals (Sweden)

    Torres-Salcido, Gerardo

    2016-06-01

    Full Text Available The prickly pear cactus is a source of food with strong bio-cultural anchorage in Mexico. This is due to at least three factors: 1 the nature and heritage of cacti; 2 cultural heritage; and 3 the socio-cultural relationships with historical and symbolic roots that have facilitated knowledge of how to cultivate it and how to use it. The aim of this article is to put factors of territorial anchorage and its historical transformation in context by examining the case of the municipality of Tlalnepantla in the state of Morelos, Mexico. This community has experienced accelerated change due to the exchange of traditional crops for the prickly pear cactus and the integration of farming, commercialization and agro-transformation. Our hypothesis is that the market, internal conflicts and a lack of socio-institutional coordination have put social organization into crisis, favoring the territorial spread of the prickly pear cactus and making the Local Agro-Food Systems (LAFS of Tlalnepantla less competitive. The conclusions highlight important economic and social advances whose roots lie in the strengthening and anchorage of the territory-product. However, circumstances both internal and external to the community persist, such as intra-community conflicts, the international market and cultural paradigm shifts that affect the producers and put consolidation of the LAFS at risk.El nopal es un alimento con un fuerte anclaje bio-cultural en México, propiciado por al menos tres factores: 1 la naturaleza y el patrimonio de cactáceas; 2 el patrimonio cultural; y, 3 las relaciones socio-culturales que han permitido un “saber hacer” y un “saber utilizar” con raíces históricas y simbólicas. El objetivo es situar los factores de anclaje territorial y su transformación histórica tomando como caso el municipio de Tlalnepantla, en el estado de Morelos, México. Esta comunidad ha experimentado un acelerado cambio por la reconversión de los cultivos

  10. Ecological Monitoring and Compliance Program 2006 Report

    Energy Technology Data Exchange (ETDEWEB)

    David C. Anderson; Paul D. Greger; Derek B. Hall; Dennis J. Hansen; William K. Ostler

    2007-03-01

    The Ecological Monitoring and Compliance program (EMAC), funded through the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), monitors the ecosystem of the Nevada Test Site (NTS) and ensures compliance with laws and regulations pertaining to NTS biota. This report summarizes the program's activities conducted by National Security Technologies LLC (NSTec) during the Calendar Year 2006. Program activities included: (a) biological surveys at proposed construction sites, (b) desert tortoise compliance, (c) ecosystem mapping and data management, (d) sensitive plant species monitoring, (e) sensitive and protected/regulated animal monitoring, (f) habitat monitoring, (g) habitat restoration monitoring, and (h) monitoring of the Nonproliferation Test and Evaluation Complex (NPTEC). Sensitive and protected/regulated species of the NTS include 44 plants, 1 mollusk, 2 reptiles, over 250 birds, and 26 mammals protected, managed, or considered sensitive as per state or federal regulations and natural resource agencies and organizations. The threatened desert tortoise (Gopherus agassizii) is the only species on the NTS protected under the Endangered Species Act. Biological surveys for the presence of sensitive and protected/regulated species and important biological resources on which they depend were conducted for 34 projects. A total of 342.1 hectares (ha) (845.37 acres [ac]) was surveyed for these projects. Sensitive and protected/regulated species and important biological resources found included: 2 inactive tortoise burrows, 2 western burrowing owls (Athene cunicularia hypugaea), several horses (Equus caballus), 2 active predator burrows, mature Joshua trees (Yucca brevifolia), yuccas and cacti; and also 1 bird nest (2 eggs), 1 barn owl (Tyto alba) and 2 great-horned owls (Bubo virginianus). NSTec provided a written summary report of all survey findings and mitigation recommendations, where applicable. All flagged burrows

  11. Ecological Monitoring and Compliance Program 2006 Report

    Energy Technology Data Exchange (ETDEWEB)

    David C. Anderson; Paul D. Greger; Derek B. Hall; Dennis J. Hansen; William K. Ostler

    2007-03-01

    The Ecological Monitoring and Compliance program (EMAC), funded through the U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), monitors the ecosystem of the Nevada Test Site (NTS) and ensures compliance with laws and regulations pertaining to NTS biota. This report summarizes the program's activities conducted by National Security Technologies LLC (NSTec) during the Calendar Year 2006. Program activities included: (a) biological surveys at proposed construction sites, (b) desert tortoise compliance, (c) ecosystem mapping and data management, (d) sensitive plant species monitoring, (e) sensitive and protected/regulated animal monitoring, (f) habitat monitoring, (g) habitat restoration monitoring, and (h) monitoring of the Nonproliferation Test and Evaluation Complex (NPTEC). Sensitive and protected/regulated species of the NTS include 44 plants, 1 mollusk, 2 reptiles, over 250 birds, and 26 mammals protected, managed, or considered sensitive as per state or federal regulations and natural resource agencies and organizations. The threatened desert tortoise (Gopherus agassizii) is the only species on the NTS protected under the Endangered Species Act. Biological surveys for the presence of sensitive and protected/regulated species and important biological resources on which they depend were conducted for 34 projects. A total of 342.1 hectares (ha) (845.37 acres [ac]) was surveyed for these projects. Sensitive and protected/regulated species and important biological resources found included: 2 inactive tortoise burrows, 2 western burrowing owls (Athene cunicularia hypugaea), several horses (Equus caballus), 2 active predator burrows, mature Joshua trees (Yucca brevifolia), yuccas and cacti; and also 1 bird nest (2 eggs), 1 barn owl (Tyto alba) and 2 great-horned owls (Bubo virginianus). NSTec provided a written summary report of all survey findings and mitigation recommendations, where applicable. All flagged burrows

  12. Biodiversity of Myxomycetes from the Monte Desert of Argentina

    Directory of Open Access Journals (Sweden)

    Lado, C.

    2011-06-01

    Full Text Available A biodiversity survey for myxomycetes was carried out in the Monte Desert (Argentina and surrounding areas in November 2006 and late February and March 2007. Specimens were collected in seven different provinces (Catamarca, Jujuy, La Rioja, Salta, San Juan, San Luis and Tucumán, between 23º and 33º S latitude, and a total of 105 localities were sampled. Cacti and succulent plants were the most common type of substrate investigated, but shrubs and herbs characteristic of this biome were also included in the survey. Almost six hundred specimens of myxomycetes from 72 different species in 22 genera were collected either in the field, or from moist chamber cultures prepared with samples of plant material obtained from the same collecting sites. The results include 1 species new to science, Macbrideola andina three more species recently described based on material from this survey, 5 species cited for the first time for the Neotropics, 11 new records for South America and 38 new records for Argentina. Taxonomic comments on rare or unusual species are included and illustrated with photographs by LM and SEM. Data are presented on the development of some species and microenvironmental factors are discussed. An analysis of the biodiversity of myxomycetes in this area, and a comparison with other desert areas, are included.

    Con el objetivo de estudiar la biodiversidad de Myxomycetes en el Desierto de Monte (Argentina y áreas circundantes, se realizó un muestreo en los meses de noviembre de 2006 y febrero y marzo de 2007. Se recolectaron especímenes en un total de 105 localidades pertenecientes a siete provincias (Catamarca, Jujuy, La Rioja, Salta, San Juan, San Luis y Tucumán, situadas entre los paralelos 23º y 33º de latitud sur. Los cactus y plantas suculentas fueron los tipos de sustratos más estudiados, pero también se analizaron arbustos y plantas herbáceas características de este bioma. Casi 600 especímenes de mixomicetes

  13. Using the Transient Electromagnetic (TEM) Method for Mapping Deep Groundwater Tables in Mars Analog Environments: a Baseline Field Study.

    Science.gov (United States)

    Jernsletten, J. A.

    2004-05-01

    INTRODUCTION: The purpose of this study is to explore the use of electromagnetic geophysical techniques for mapping deep groundwater tables in Mars analog environments. In order to provide a baseline for such studies, and to evaluate the appropriateness of the Transient Electro-Magnetic (TEM) method in mapping deep groundwater tables, a field study was carried out in an area in the desert approximatelt 30 miles southwest of Tucson Arizona. The field area was chosen for its convenient logistics and access to technical support, as well as for its appropriateness as a baseline Mars analog site. DISCUSSION: The surface conditions at the site are less than ideal if the main motivation is to look for analogs for surface working conditions on Mars, due to a fairly dense cover of cacti and thorny brush. However, in a situation like in the present study, where the subsurface analog is of more interest, vegetation cover is only a logistical issue. The subsurface in the field area is quite conductive, a result of its clay-rich soil, and this may at first thought seem to make it a less than ideal location for Mars analog studies. The contrary is the case, however: In having to deal with the very conductive environment at the field area location for this baseline study, it is ensured that results and conclusions drawn from this work regarding issues such as working in a conductive environment and achieving certain depths of investigation can indeed be applied to planning field studies elsewhere. Further, the study is also designed to observe the effects of powerline noise on electromagnetic data, again presenting a very-difficult case, and further aiding in building a baseline case that is overall appropriately more difficult than most field studies will be (in terms of achieving good signal-to-noise ratios and depths of investigation). The field survey consisted of 40 in-loop TEM stations, divided into 3 lines, for 4 line-km of data. The survey was carried out by a crew of one

  14. Anatomy of Brazilian Cereeae (subfamily Cactoideae, Cactaceae: Arrojadoa Britton & Rose, Stephanocereus A. Berger and Brasilicereus Backeberg Anatomia de espécies brasileiras pertencentes à tribo Cereeae (subfamília Cactoideae, Cactaceae: Arrojadoa Britton & Rose, Stephanocereus A. Berger and Brasilicereus Backeberg

    Directory of Open Access Journals (Sweden)

    Patricia Soffiatti

    2007-12-01

    Full Text Available (Anatomy of Brazilian Cereeae (subfamily Cactoideae, Cactaceae: Arrojadoa Britton & Rose, Stephanocereus A. Berger wâBrasilicereus Backeberg. Arrojadoa, Stephanocereus and Brasilicereus are endemic Brazilian Cereeae, occurring along the Espinhaço Range, in the campos rupestres, cerrados and caatingas, from northern Minas Gerais to southern Bahia. The genera are columnar, erect to semi-erect cacti, except for one species, A bahiensis, which is globose. This study describes the anatomy of dermal, fundamental and vascular systems, aiming to find diagnostic characters for the genera and species. Basal portions of stems were sectioned transversely and longitudinally, and stained with Astrablue and Safranin. The species share a uniseriate epidermis, with thick cuticle; well developed collenchymatic hypodermis, containing prismatic crystals; cortex with numerous mucilage cells, druses and vascular bundles; outside cortex as a palisade parenchyma; periderm composed of lignified cork cells alternating with suberized cells; pheloderm consisting of a few layers of thin-walled cells; phloem composed of solitary or multiple of two to three sieve tube elements, companion cells, axial and radial parenchyma; secondary xylem with solitary to multiple vessels, with simple perforation plates and alternate bordered to semi-bordered pits; axial parenchyma scanty vasicentric to incomplete; libriform septate fibres; large rays. Unlignified parenchyma is seen in the secondary xylem, varying from a few cells to bands among axial and radial elements. The following are considered diagnostic characters: the shape of lignified phellem cells, cubic to radially elongate, which individualizes S. leucostele; an underdeveloped hypodermis and the occurrence of sclereids in the cortex are exclusive to Brasilicereus markgrqfii.(Anatomia de espécies brasileiras pertencentes à tribo Cereeae (subfamília Cactoideae, Cactaceae: Arrojadoa Britton & Rose, Stephanocereus A. Berger and

  15. Myxomycete diversity of the Patagonian Steppe and bordering areas in Argentina

    Directory of Open Access Journals (Sweden)

    Lado, Carlos

    2014-06-01

    Full Text Available Biodiversity surveys for myxomycetes (Amoebozoa were carried out in three consecutive years (2009 to 2011 in the cold arid Patagonian Steppe, Argentina. The surveys, the first to cover such an extensive area in South America, form part of the Myxotropic project funded by the Spanish Government. Specimens were collected in 174 localities in four different provinces (Neuquén, Río Negro, Chubut and Santa Cruz, between 36° and 52° S latitudes. The most common types of substrate investigated were the dominant shrubs and grasses of the Patagonian steppe, and the Nothofagus forests, characteristic of the transition areas, but other plants such as small cacti and cushion plants were also included in the survey. A total of 133 different species and 5 varieties of myxomycetes representing 31 genera were identified in the 1134 specimens collected either in the field, or from moist chamber cultures prepared with samples of plant material obtained from the same collecting sites. The results include one species new to science, Perichaena nigra, and 17 species and two varieties that were previously unknown for either the Neotropics or South America, Badhamia armillata, Dianema mongolicum, Didymium annulisporum, D. leptotrychum, D. orthonemata, D. sturgisii, Echinostelium coelocephalum, Licea deplanata, L. nannengae, Macbrideola argentea, M. oblonga, Oligonema aurantium, Perichaena luteola, P. madagascariensis, Physarum luteolum, Protophysarum phloiogenum, Trichia contorta var. attenuata, T. contorta var. iowensis, T. erecta. An additional 19 species are new records for Argentina. These additions make Argentina the country in South America, at present, with the greatest number of myxomycetes catalogued having more than 50% of the species cited from the whole Neotropics. Diversity and biogeographic distribution of these organisms are discussed, and taxonomic comments on rare or unusual species are included and illustrated with photographs by LM and SEM. The

  16. Novel ideas for maximising dew collection to aid plant establishment to combat desertification and restore degraded dry and arid lands

    Science.gov (United States)

    Kotzen, Benz

    2014-05-01

    and numerous studies have been undertaken to investigate past so-called dew collectors and to research the possibilities of using new ones. Most of the historical dew collectors have been disputed as dew collection devices. (Beysens et al 2006, Beysens et al in Kogan and Trahtman 2006, Graf et al 2008.) However, contemporary dew collection has proven possible in those areas that have dew fall. It is generally agreed by researchers, such as Sharan and Beysens in 2007 and Jacobs et al in 2008 after Monteith (1957) that the theoretical maximum dew yield is in the order of 0.8 l/m2/day. Although the exact maximum has never been defined the amounts can yet be significant. However, In most cases the investigations of dew supply in areas where dew is known to precipitate has been undertaken with inclined roof like planar surfaces. However, erecting these planes in remote areas and within difficult terrain makes this kind of collector impractical. Additionally such planar surfaces demand space on the ground which then diminishes the areas of restoration and large collectors require additional plumbing to distribute water to the plants themselves. Thus in order to better supply dew to plants other forms are required. This paper discusses the various ideas and concepts that have been developed for dew collection that have emerged on the market and the novel ideas that have been initiated by the author. The research undertaken investigates biomimetic forms which emulate plant forms such as various cacti and succulents investigating their ability to increase surface area as well as releasing heat like a radiator. Additionally other spiky, needle like forms are investigated as well as animal forms, such as the surface of the Stenocara gracilipes Namibian beetle which collects fog. The research initiated a new strategy for dew collection dividing dew collectors into two types: 1) Passive dew collectors, where nightly collection and delivery is achieved without people, and 2) Semi

  17. Novel ideas for maximising dew collection to aid plant establishment to combat desertification and restore degraded dry and arid lands

    Science.gov (United States)

    Kotzen, Benz

    2014-05-01

    and numerous studies have been undertaken to investigate past so-called dew collectors and to research the possibilities of using new ones. Most of the historical dew collectors have been disputed as dew collection devices. (Beysens et al 2006, Beysens et al in Kogan and Trahtman 2006, Graf et al 2008.) However, contemporary dew collection has proven possible in those areas that have dew fall. It is generally agreed by researchers, such as Sharan and Beysens in 2007 and Jacobs et al in 2008 after Monteith (1957) that the theoretical maximum dew yield is in the order of 0.8 l/m2/day. Although the exact maximum has never been defined the amounts can yet be significant. However, In most cases the investigations of dew supply in areas where dew is known to precipitate has been undertaken with inclined roof like planar surfaces. However, erecting these planes in remote areas and within difficult terrain makes this kind of collector impractical. Additionally such planar surfaces demand space on the ground which then diminishes the areas of restoration and large collectors require additional plumbing to distribute water to the plants themselves. Thus in order to better supply dew to plants other forms are required. This paper discusses the various ideas and concepts that have been developed for dew collection that have emerged on the market and the novel ideas that have been initiated by the author. The research undertaken investigates biomimetic forms which emulate plant forms such as various cacti and succulents investigating their ability to increase surface area as well as releasing heat like a radiator. Additionally other spiky, needle like forms are investigated as well as animal forms, such as the surface of the Stenocara gracilipes Namibian beetle which collects fog. The research initiated a new strategy for dew collection dividing dew collectors into two types: 1) Passive dew collectors, where nightly collection and delivery is achieved without people, and 2) Semi

  18. Ecological Monitoring and Compliance Program 2014 Report

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Derek B. [National Security Technologies, LLC, Las Vegas, Nevada (United States); Anderson, David C. [National Security Technologies, LLC, Las Vegas, Nevada (United States); Greger, Paul D. [National Security Technologies, LLC, Las Vegas, Nevada (United States); Ostler, W. Kent [National Security Technologies, LLC, Las Vegas, Nevada (United States)

    2015-05-12

    (Crotalus mitchellii), and several species of cacti. NSTec provided to project managers a written summary report of all survey findings and mitigation recommendations, where applicable. Of the 18 projects on the NNSS, 15 occurred within the range of the threatened desert tortoise. Approximately 2.19 ha of desert tortoise habitat were disturbed. No desert tortoises were accidentally injured or killed by project activities, and no tortoises were killed by vehicles. On 13 occasions, tortoises were moved off the road and out of harm’s way. Six tortoises were found and transmitters attached as part of an approved study to assess impacts of vehicles on tortoises on the NNSS. NSTec biologists continued to monitor 37 juvenile desert tortoises as part of a collaborative effort to study survival and temperament of translocated animals. From 1978 until 2013, there has been an average of 11.2 wildland fires per year on the NNSS with an average of about 83.7 ha burned per fire. There were no wildland fires documented on the NNSS during 2014. Results from the wildland fuel surveys showed a very low risk of wildland fire due to reduced fuel loads caused by limited natural precipitation. Limited reptile trapping and reptile roadkill surveys were conducted to better define species distribution on the NNSS. Sixteen reptiles were trapped representing five species. Combined with data from 2013, 183 road kills were detected, representing 11 snake and 8 lizard species. Selected natural water sources were monitored to assess trends in physical and biological parameters, and one new water source was found. Wildlife use at five water troughs and four radiologically contaminated sumps was documented using motion-activated cameras. As part of the statewide effort to disseminate information throughout the botanical community, NSTec prepared a shape file with site-specific data for all 17 sensitive plants on the NNSS and provided it to the Nevada Natural Heritage Program for inclusion in their