WorldWideScience

Sample records for cacti

  1. 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.

  2. 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

    BACKGROUND: Occupational exposure to Christmas cacti has been reported as a cause of type I allergy. Therefore, the prevalence of immediate-type mucosal and skin reactions related to cactus exposure was studied in 103 employees in a cactus nursery. METHODS: The study was based on a questionnaire...... and mucosal symptoms. CONCLUSIONS: Christmas and Easter cacti seemed to be able to induce contact urticaria and rhinoconjunctivitis on both an immunologic and a nonimmunologic basis. Personal atopy was associated with positive reactions to cacti....

  3. 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.

  4. 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

  5. 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...

  6. 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.

  7. 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.

  8. 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...

  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. 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

  11. 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

  12. 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.

  13. 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.

  14. 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

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Low- and High-Temperature Tolerance and Acclimation for Chlorenchyma versus Meristem of the Cultivated Cacti Nopalea cochenillifera, Opuntia robusta, and Selenicereus megalanthus

    Directory of Open Access Journals (Sweden)

    Brian R. Zutta

    2011-01-01

    Full Text Available Dividing meristematic cells are thought to be more sensitive to extreme temperatures compared to other tissues, such as chlorenchyma. This was examined for low and high temperatures for three widely cultivated cacti: Nopalea cochenillifera, Opuntia robusta, and Selenicereus megalanthus. Temperature tolerances of chlorenchyma and meristem were based on the cellular uptake of the vital stain neutral red for plants at mean day/night air temperatures of 25/20°C and plants maintained at 10/5°C or 45/40°C to examine temperature acclimation. Meristematic cells tolerated 1.8°C lower low temperatures and 4.0°C higher high temperatures than chlorenchyma cells for the three species at 25/20°C. Both tissue types showed acclimation, with a decrease or increase in temperature tolerated at 10/5°C or 45/40°C, respectively. Meristematic cells were more tolerant of extreme temperatures compared to chlorenchyma, contrary to the prevailing belief, and may reflect an additional strategy for cacti to survive extreme temperatures.

  3. 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

  4. 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).

  5. 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

  6. 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

  7. 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

  8. 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...

  9. 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…

  10. 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.

  11. Distribution and habitat in Mexico of Dactylopius Costa (Hemiptera: Dactylopiidae) and their cacti hosts (Cactaceae: Opuntioideae).

    Science.gov (United States)

    Chávez-Moreno, C K; Tecante, A; Casas, A; Claps, L E

    2011-01-01

    The distribution pattern of species of the genus Dactylopius Costa in Mexico was analyzed in relation to the distribution of their host plants (subfamily Opuntioideae) to evaluate the specificity of the insect-host association. The distribution of Dactylopius currently recognized is narrower than that of its hosts and probably is not representative. Therefore, a broader distribution of the Dactylopius species in correspondence with those of their hosts was hypothesized. Insects and their hosts were collected and georeferenced in 14 states of Mexico from 2005 to 2007. The distribution areas, maps, and habitat characteristics of Dactylopius, Opuntia sensu stricto, Nopalea and Cylindropuntia were determined on the basis of field collections and examination of museum collections. This information was complemented with information from the exhaustive examination of microscope slides from a local insect collection, plants from local herbaria, and literature reviews. The current distribution of the genus Dactylopius and its hosts included 22 and 25 states of Mexico, respectively, and Dactylopius had a continuous distribution according to its hosts, broader than recognized hitherto. The new georeferenced records of the five Mexican Dactylopius species are reported. Insects with morphological characteristics of D. confusus combined with those of D. salmianus were identified, as well as insects with characteristics of D. opuntiae combined with those of D. salmianus. These records suggest that the number of local Dactylopius species could be higher than previously thought or that possible new processes of hybridization between native and introduced species may be occurring. PMID:21437484

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. Implementation of Radio and Television Multi Service Network Traffic Monitoring based on Cacti%基于Cacti实现广电多业务网络流量监控的成功探索

    Institute of Scientific and Technical Information of China (English)

    夏仁辉

    2013-01-01

    随着全球信息化的高速发展,计算机网络越来越成为不可或缺的数据载体。广电新媒体业务的发展和壮大,也要求我们能够更好地掌控业务数据。讨论广电运营商在开展诸如宽带、IPTV等新业务过程中,如何利用高效的监控工具实现对各种新业务网络IP流量的可视化监测。%With the rapid development of global information technology , computer network has increasingly be-come an indispensable data carrier .The development of Broadcast &TV New Media requires us to be able to better control the business data .The purpose of this paper is to discuss the development of radio and television operators in such as broadband , IPTV and other new business process , how to use the monitoring tool for effi-cient implementation of visual monitoring of various new business network IP traffic .

  18. 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.

  19. 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.

  20. 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.

  1. 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...

  2. 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.

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

    DEFF Research Database (Denmark)

    Paulsen, E; Skov, Per Stahl; Andersen, Klaus Ejner

    1998-01-01

    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...

  4. 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

  5. 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.

  6. 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.

  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. 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

  9. 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.

  10. Mescaline: a survey.

    Science.gov (United States)

    Schwartz, R H

    1988-04-01

    The hallucinogen mescaline is found in the peyote and San Pedro cacti, which are prevalent in Mexico and the southwestern United States. In a survey of middle-class, predominantly white adolescents in a drug treatment facility, 18 percent of the respondents indicated that they had taken mescaline. Much of the purported mescaline was probably another hallucinogen, usually LSD. The effects of equipotent doses of mescaline and LSD are almost indistinguishable.

  11. Pollination system of the Pilosocereus leucocephalus columnar cactus (tribe Cereeae) in eastern Mexico.

    Science.gov (United States)

    Munguía-Rosas, M A; Sosa, V J; Jácome-Flores, M E

    2010-07-01

    It has been suggested that there is a geographic dichotomy in the pollination systems of chiropterophilous columnar cacti: in intra-tropical areas they are pollinated almost exclusively by bats, whereas in extratropical areas they are pollinated by bats, birds and bees. However, currently the studies are clumped both taxonomically (mainly Pachycereeae species) and geographically (mainly in the Tehuacan Valley and the Sonoran Desert). This clumping limits the possibility of generalising the pattern to other regions or cactus tribes. Only four of the 36 chiropterophilous cacti in Pilosocereus have been studied. Despite the tropical distribution of two Pilosocereus species, bees account for 40-100% of their fruit set. We examined how specialised is the pollination system of P. leucocephalus in eastern Mexico. As we studied tropical populations, we expected a bat-specialised pollination system. However, previous studies of Pilosocereus suggest that a generalised pollination system is also possible. We found that this cactus is mainly bat-pollinated (bats account for 33-65% of fruit set); although to a lesser degree, diurnal visitors also caused some fruit set (7-15%). Diurnal visitors were more effective in populations containing honeybee hives. P. leucocephalus is partially self-compatible (14-18% of fructification) but unable to set fruit without visitors. Despite the variation in pollination system, P. leucocephalus shows more affinity with other columnar cacti from tropical regions than with those from extratropical regions. Although we report here that a new species of tropical Pilosocereus is relatively bat-specialised, this Cereeae genus is more flexible in its pollination system than the Pachycereeae genera.

  12. 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

  13. 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...

  14. A new Anagyrus (Hymenoptera: Encyrtidae) from Argentina, parasitoid of Hypogeococcus sp. (Hemiptera: Pseudococcidae) on Harrisia pomanensis (Cactaceae).

    Science.gov (United States)

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

    2016-05-26

    A new species of Anagyrus Howard (Hymenoptera: Encyrtidae), A. lapachosus sp. n., is described from Salta Province of Argentina as a parasitoid of Hypogeococcus sp. (Hemiptera: Pseudococcidae) on Harrisia pomanensis cactus (Cactaceae). It is a candidate "new association" biological control agent for quarantine evaluation and possible following introduction to Puerto Rico (USA) against another Hypogeococcus sp., commonly called the Harrisia cactus mealybug and often misidentified as H. pungens Granara de Willink (according to our unpublished data the latter attacks only Amaranthaceae), which devastates or threatens the native cacti there and also in some other Caribbean islands (Triapitsyn, Aguirre et al. 2014; Carrera-Martínez et al. 2015).

  15. 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.

  16. 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

  17. 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.

  18. 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.

  19. 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...... 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...... 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 MSn, and provide...

  20. 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

    2014-09-15

    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. 

  1. 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

  2. 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

  3. 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

  4. SNMP-based Monitoring of the Campus Network System%基于SNMP的校园网监控系统的应用

    Institute of Scientific and Technical Information of China (English)

    吴许俊

    2009-01-01

    如何监管日益复杂的计算机网络是一个紧迫的问题.本文阐述了基于SNMP的监控系统体系结构,介绍了SNMP的应用实例--建设基于Cacti的校园网监控系统及其在校园网监控管理中的具体应用.%How to monitor the increasingly complex structure of the computer network is becoming an urgent issue. In this paper, the writer illustrates the monitoring system based on the SNMP, and introduces the application of SNMP--the construction of Cacti-based monitoring system of the campus network and its specific applications in the campus network monitoring aad management.

  5. 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.

  6. 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.

  7. Progress in long-lived radioactive waste management and disposal at the waste isolation pilot plant

    Energy Technology Data Exchange (ETDEWEB)

    Triay, I.R.; Matthews, M.L. [U.S. Dept. of Energy Carlsbad Field Office, New Mexico (United States); Eriksson, L.G. [GRAM, Inc., Albuquerque, NM (United States)

    2001-07-01

    The Salado Formation is buried more than 350 m beneath the sands and cacti of the Chihuahuan Desert and hosts the Waste Isolation Pilot Plant (WIPP) deep geological repository at a depth of approximately 650 m. Since the WIPP repository is at least 10 years ahead of any other repository development for long-lived radioactive waste, other radioactive waste management organizations and institutions could benefit both scientifically and politically from sharing the lessons learned at WIPP. Benefits would include using existing expertise and facilities to cost-effectively address and solve program-specific issues and to train staff. The characteristics of the WIPP repository and infrastructure are described in this paper. (author)

  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. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. Environmental isolation and characterisation of Cryptococcus species from living trees in Havana city, Cuba.

    Science.gov (United States)

    Illnait-Zaragozí, M T; Martínez-Machín, G F; Fernández-Andreu, C M; Perurena-Lancha, M R; Theelen, B; Boekhout, T; Meis, J F; Klaassen, C H

    2012-05-01

    Cryptococcus isolates from Cuban patients were identified as C. neoformans var. grubii. Although this species has since long been associated with bird droppings, a recent genotyping study provided strong evidence for additional origins of exposure. We sampled different species of trees in Havana, Cuba to identify other potential sources of exposure to this fungus. A total of 662 samples were collected from 331 trees and cacti from Havana, Cuba. Initial selection of the isolates was carried out by conventional techniques. Isolates were further characterised using a combination of AFLP analysis and DNA sequence analysis. Identification by conventional methods yielded 121 C. neoformans and 61 C. gattii isolates. Molecular analyses showed that none of these isolates was C. gattii and only one isolate proved to be C. neoformans var. grubii. A total of 27 different other species were identified. The most prevalent species was C. heveanensis (33%). Sixty-five unidentifiable isolates segregated into ten potentially novel species. Conventional cultivation methods have a low specificity for C. neoformans complex and molecular analyses need to be applied to confirm identification of isolates from environmental sources. Environmental niches responsible for most of human cryptococcal infections in Cuba remain to be identified.

  17. Herbivore-mediated ecological costs of reproduction shape the life history of an iteroparous plant.

    Science.gov (United States)

    Miller, Tom E X; Tenhumberg, Brigitte; Louda, Svata M

    2008-02-01

    Plant reproduction yields immediate fitness benefits but can be costly in terms of survival, growth, and future fecundity. Life-history theory posits that reproductive strategies are shaped by trade-offs between current and future fitness that result from these direct costs of reproduction. Plant reproduction may also incur indirect ecological costs if it increases susceptibility to herbivores. Yet ecological costs of reproduction have received little empirical attention and remain poorly integrated into life-history theory. Here, we provide evidence for herbivore-mediated ecological costs of reproduction, and we develop theory to examine how these costs influence plant life-history strategies. Field experiments with an iteroparous cactus (Opuntia imbricata) indicated that greater reproductive effort (proportion of meristems allocated to reproduction) led to greater attack by a cactus-feeding insect (Narnia pallidicornis) and that damage by this herbivore reduced reproductive success. A dynamic programming model predicted strongly divergent optimal reproductive strategies when ecological costs were included, compared with when these costs were ignored. Meristem allocation by cacti in the field matched the optimal strategy expected under ecological costs of reproduction. The results indicate that plant reproductive allocation can strongly influence the intensity of interactions with herbivores and that associated ecological costs can play an important selective role in the evolution of plant life histories.

  18. The form of sexual selection arising from male-male competition depends on the presence of females in the social environment.

    Science.gov (United States)

    Procter, D S; Moore, A J; Miller, C W

    2012-05-01

    Sexual selection arises from social interactions, and if social environments vary so too should sexual selection. For example, male-male competition often occurs either in the presence or in the absence of females, and such changes in the social environment could affect the form and strength of sexual selection. Here we examine how the presence of a female influences selection arising from male-male competition in a leaf-footed cactus bug, Narnia femorata, which has a resource defence mating system. Males compete for territories on cacti because females lay eggs on the cactus plants. Females are not always present when this competition first occurs; however, the presence or absence of the female matters. We found that both the form and strength of selection on male traits, those traits that influenced success in intrasexual competition, depended on the social context. When a female was not present, male size and the area of the sexually dimorphic hind legs was only marginally important to winning a contest. However, males with larger overall size and leg area were more likely to win in the presence of a female. There was also positive quadratic selection on these traits when a female was present with both the largest and the smallest males winning. The implication is unexpected alternative strategies when females are present. Our results support the notion that sexual selection should be studied under all relevant social contexts.

  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. Phylogenetic origins of Lophocereus (Cactaceae) and the senita cactus-senita moth pollination mutualism.

    Science.gov (United States)

    Hartmann, Stefanie; Nason, John D; Bhattacharya, Debashish

    2002-07-01

    Recent ecological research has revealed that the Sonoran Desert columnar cactus Lophocereus and the pyralid moth Upiga virescens form an obligate pollination mutualism, a rare but important case of coevolution. To investigate the phylogenetic origins of this unusual pollination system, we used molecular sequence data to reconstruct the phylogeny of the four taxa within the genus Lophocereus and to determine the phylogenetic position of Lophocereus within the North American columnar cacti (tribe Pachycereeae). Our analysis included Lophocereus, six Pachycereus species, Carnegiea gigantea, and Neobuxbaumia tetetzo within the subtribe Pachycereinae, and Stenocereus thurberi as an outgroup within the Stenocereinae. Extensive screening of chloroplast and mitochondrial genomes failed to reveal sequence variation within Lophocereus. At a deeper phylogenetic level, however, we found strong support for the placement of Lophocereus within Pachycereus as sister group to the hummingbird-pollinated P. marginatus. We discuss possible hypotheses that may explain the transition from bat pollination (ancestral) to moth and hummingbird pollination in Lophocereus and P. marginatus, respectively. Additional phylogenetic analyses suggest that the genus Pachycereus should be expanded to include Lophocereus, Carnegiea, Neobuxbaumia, and perhaps other species, whereas P. hollianus may need to be excluded from this clade. Future study will be needed to test taxonomic distinctions within Lophocereus, to test for parallel cladogenesis between phylogroups within Lophocereus and Upiga, and to fully delineate the genus Pachycereus and relationships among genera in the Pachycereinae.

  1. 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

  2. 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.

  3. 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

  4. 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.

  5. 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

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

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    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.

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. Hybridization between Dactylopius tomentosus (Hemiptera: Dactylopiidae) biotypes and its effects on host specificity.

    Science.gov (United States)

    Mathenge, C W; Holford, P; Hoffmann, J H; Zimmermann, H G; Spooner-Hart, R N; Beattie, G A C

    2010-06-01

    Dactylopius tomentosus is composed of biotypes adapted to different Cylindropuntia species. One biotype is an important biological control agent of C. imbricata in South Africa while another has the potential for the control of C. fulgida var. fulgida. These two weed species occur in sympatry in some areas of South Africa, so the introduction of the second biotype could result in hybridization, which, in turn, could impact on the biological control programs through altered host specificity and fitness of the hybrids. To anticipate what might happen, reciprocal crosses were made between the two biotypes, and the biological performance of the resultant hybrids was compared with that of each parental lineage on C. imbricata and C. f. var. fulgida. The biotypes interbred freely and reciprocally in the laboratory. Comparisons of crawler and adult female traits showed differences in performance that were dependent on the origin of the maternal and paternal genomes. However, when all traits were combined into a 'fitness index', both hybrids clearly outperformed the parental lineages. The increase in fitness shown by the hybrids over their maternal lineage was greater on the alternative host of the maternal parent than on the natural host of the maternal parent. Therefore, in areas where the two cacti occur in sympatry, hybridization between the biotypes is not expected to be detrimental to the biological control of either weed. PMID:20074385

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

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    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.

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

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    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.

  14. 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.

  15. 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.

  16. 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

  17. 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.

  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. 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

  20. 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.

  1. 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.

  2. Sonoran Desert: Fragile Land of Extremes

    Science.gov (United States)

    Produced and Directed by Wessells, Stephen

    2003-01-01

    'Sonoran Desert: Fragile Land of Extremes' shows how biologists with the U.S. Geological Survey work with other scientists in an effort to better understand native plants and animals such as desert tortoises, saguaro cacti, and Gila monsters. Much of the program was shot in and around Saguaro National Park near Tucson, Arizona. Genetic detective work, using DNA, focuses on understanding the lives of tortoises. Studies of saguaros over many decades clarify how these amazing plants reproduce and thrive in the desert. Threats from fire, diseases in tortoises, and a growing human population motivate the scientists. Their work to identify how these organisms live and survive is a crucial step for the sound management of biological resources on public lands. This 28-minute program, USGS Open-File Report 03-305, was shot entirely in high definition video and produced by the USGS Western Ecological Research Center and Southwest Biological Science Center; produced and directed by Stephen Wessells, Western Region Office of Communications.

  3. 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

  4. 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.

  5. Density-mediated, context-dependent consumer-resource interactions between ants and extrafloral nectar plants.

    Science.gov (United States)

    Chamberlain, Scott A; Holland, J Nathaniel

    2008-05-01

    Interspecific interactions are often mediated by the interplay between resource supply and consumer density. The supply of a resource and a consumer's density response to it may in turn yield context-dependent use of other resources. Such consumer-resource interactions occur not only for predator-prey and competitive interactions, but for mutualistic ones as well. For example, consumer-resource interactions between ants and extrafloral nectar (EFN) plants are often mutualistic, as EFN resources attract and reward ants which protect plants from herbivory. Yet, ants also commonly exploit floral resources, leading to antagonistic consumer-resource interactions by disrupting pollination and plant reproduction. EFN resources associated with mutualistic ant-plant interactions may also mediate antagonistic ant-flower interactions through the aggregative density response of ants on plants, which could either exacerbate ant-flower interactions or alternatively satiate and distract ants from floral resources. In this study, we examined how EFN resources mediate the density response of ants on senita cacti in the Sonoran Desert and their context-dependent use of floral resources. Removal of EFN resources reduced the aggregative density of ants on plants, both on hourly and daily time scales. Yet, the increased aggregative ant density on plants with EFN resources decreased rather than increased ant use of floral resources, including contacts with and time spent in flowers. Behavioral assays showed no confounding effect of floral deterrents on ant-flower interactions. Thus, ant use of floral resources depends on the supply of EFN resources, which mediates the potential for both mutualistic and antagonistic interactions by increasing the aggregative density of ants protecting plants, while concurrently distracting ants from floral resources. Nevertheless, only certain years and populations of study showed an increase in plant reproduction through herbivore protection or ant

  6. 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

  7. Development and clinical application of an LC-MS-MS method for mescaline in urine.

    Science.gov (United States)

    Björnstad, Kristian; Helander, Anders; Beck, Olof

    2008-04-01

    Mescaline (3,4,5-trimethoxyphenylethylamine) is an hallucinogenic psychoactive substance present in several species of cacti. Mescaline has a documented use dating back 5700 years. In more recent years, the interest in hallucinogenic designer drugs such as ecstasy has also triggered interest in the naturally occurring mescaline. This study was undertaken to develop a liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the screening and confirmation of mescaline in human urine samples and to apply this method to routine testing in patient samples. For the screening procedure, chromatographic separation was achieved on a 5-microm HyPURITY C(18) column, using a methanol gradient in ammonium acetate buffer. The MS-MS analysis was performed using selected reaction monitoring; the transitions monitored were m/z 212.3 --> m/z 180.3 for mescaline and m/z 221.3 --> m/z 186.3 for the deuterated internal standard (mescaline-d(9)). The detection limit for mescaline in urine matrix was 3-5 microg/L, the upper limit of quantification was 10,000 microg/L, and the total coefficient of variation for spiked samples containing 10 to 1025 microg/L was mescaline (m/z 212.3 --> m/z 195.2) was monitored. The LC-MS-MS method was found to be sensitive and specific for the routine detection of mescaline in urine. Among 462 urine samples collected from young people with alcohol or drug problems, 32% were positive for illicit drugs, but none for mescaline.

  8. Ecophysiological and anatomical mechanisms behind the nurse effect: which are more important? A multivariate approach for cactus seedlings.

    Directory of Open Access Journals (Sweden)

    Pablo Delgado-Sánchez

    Full Text Available BACKGROUND: Cacti establish mostly occurs under the canopy of nurse plants which provide a less stressful micro-environment, although mechanisms underlying this process are unknown. The impact of the combination of light and watering treatments on Opuntia streptacantha (Cactaceae seedlings was examined. METHODS/PRINCIPAL FINDINGS: Ecophysiological [titratable acidity, osmotic potential ('solute potential', Ψs , relative growth rate (RGR and their components (NAR, SLA, and LWR], anatomical (chloroplast density, chloroplast frequency, and cell area, and environmental [photosynthetic photon flux density (PPFD and air temperature] sets of variables were analyzed, assessing relationships between them and measuring the intensity of the relationships. Three harvests were carried out at days 15, 30, and 45. Ψs and acidity content were the most important responses for seedling establishment. The main anatomical and environmental variables were chloroplast density and water availability, respectively. Opuntia streptacantha seedlings establish better in the shade-watering treatment, due to higher Ψs and acidity, unaffected chloroplasts, and lower PPFD. In addition, the chloroplasts of cells under high-light and non-watering treatment were clumped closer to the center of the cytosol than those under shade-drought, to avoid photoinhibition and/or to better distribute or utilize the penetrating light in the green plant tissue. CONCLUSIONS: Opuntia seedlings grow better under the shade, although they can tolerate drought in open spaces by increasing and moving chloroplasts and avoiding drastic decreases in their Ψs . This tolerance could have important implications for predicting the impact of climate change on natural desert regeneration, as well as for planning reforestation-afforestation practices, and rural land uses.

  9. 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

  10. 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.

  11. Traumatic brain injury and vestibulo-ocular function: current challenges and future prospects

    Directory of Open Access Journals (Sweden)

    Wallace B

    2016-09-01

    Full Text Available Bridgett Wallace,1–4 Jonathan Lifshitz4–8 1360 Balance and Hearing, Department of Physical Therapy, Austin, TX, 2Concussion Health, Department of Clinical Education, Austin, TX, 3Conquering Concussions, Scottsdale, AZ, 4Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ, 5Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 6The CACTIS Foundation, Scottsdale, 7Phoenix VA Healthcare System, Phoenix, AZ, 8Department of Psychology, Arizona State University, Tempe, AZ, USA Abstract: Normal function of the vestibulo-ocular reflex (VOR coordinates eye movement with head movement, in order to provide clear vision during motion and maintain balance. VOR is generated within the semicircular canals of the inner ear to elicit compensatory eye movements, which maintain stability of images on the fovea during brief, rapid head motion, otherwise known as gaze stability. Normal VOR function is necessary in carrying out activities of daily living (eg, walking and riding in a car and is of particular importance in higher demand activities (eg, sports-related activities. Disruption or damage in the VOR can result in symptoms such as movement-related dizziness, blurry vision, difficulty maintaining balance with head movements, and even nausea. Dizziness is one of the most common symptoms following traumatic brain injury (TBI and is considered a risk factor for a prolonged recovery. Assessment of the vestibular system is of particular importance following TBI, in conjunction with oculomotor control, due to the intrinsic neural circuitry that exists between the ocular and vestibular systems. The purpose of this article is to review the physiology of the VOR and the visual-vestibular symptoms associated with TBI and to discuss assessment and treatment guidelines for TBI. Current challenges and future prospects will also be addressed. Keywords: traumatic brain injury, concussion, vestibular, ocular

  12. Determination of biotypes of Dactylopius tomentosus (Hemiptera: Dactylopiidae) and insights into the taxonomic relationships of their hosts, Cylindropuntia spp.

    Science.gov (United States)

    Mathenge, C W; Holford, P; Hoffmann, J H; Zimmermann, H G; Spooner-Hart, R; Beattie, G A C

    2010-06-01

    Host specialization to form biotypes is common among phytophagous insects, and it has been hypothesised that biotypes of Dactylopius tomentosus L. (Hemiptera: Dactylopiidae) occur. D. tomentosus is an important biological control agent for Cylindropuntia cacti when they occur as weeds. Additionally, there is uncertainty surrounding the taxonomic status of some species of Cylindropuntia. This study aimed to confirm the existence of D. tomentosus biotypes and to assess whether host specialization can help to resolve this systematic uncertainty. For this study, the host specificity and performance of ten provenances of D. tomentosus collected from C. cholla, C. fulgida var. fulgida, C. imbricata, C. f. var. mamillata, C. rosea and C. tunicata and reared on C. cholla, C. fulgida var. fulgida, C. imbricata and C. rosea were investigated. Five life-history parameters were measured including: crawler development time and survival, female development time, and the weight and number of eggs produced by females. Results revealed significant variation in host specificity with provenances either thriving, surviving or dying on the different hosts, thus demonstrating the existence of biotypes. Also, host specificity was related to host species and not to the geographic locality from which either the host or provenance was sourced. These findings suggest that the characteristics of Cylindropuntia species may differ sufficiently, there by presenting different selection pressures that induce and sustain distinct biotypes of D. tomentosus. The observed host use patterns of the biotypes separated the plant species into two groups that accorded with known phylogenetic relationships among Cylindropuntia species, suggesting that biotypes can be used to elucidate their taxonomic relatedness. Besides advancing our knowledge of the ecology and evolution of D. tomentosus, these novel findings have important implications for the biological control of Cylindropuntia species. PMID:20003574

  13. 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

  14. Opuntia in Mexico: identifying priority areas for conserving biodiversity in a multi-use landscape.

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    Patricia Illoldi-Rangel

    Full Text Available BACKGROUND: México is one of the world's centers of species diversity (richness for Opuntia cacti. Yet, in spite of their economic and ecological importance, Opuntia species remain poorly studied and protected in México. Many of the species are sparsely but widely distributed across the landscape and are subject to a variety of human uses, so devising implementable conservation plans for them presents formidable difficulties. Multi-criteria analysis can be used to design a spatially coherent conservation area network while permitting sustainable human usage. METHODS AND FINDINGS: Species distribution models were created for 60 Opuntia species using MaxEnt. Targets of representation within conservation area networks were assigned at 100% for the geographically rarest species and 10% for the most common ones. Three different conservation plans were developed to represent the species within these networks using total area, shape, and connectivity as relevant criteria. Multi-criteria analysis and a metaheuristic adaptive tabu search algorithm were used to search for optimal solutions. The plans were built on the existing protected areas of México and prioritized additional areas for management for the persistence of Opuntia species. All plans required around one-third of México's total area to be prioritized for attention for Opuntia conservation, underscoring the implausibility of Opuntia conservation through traditional land reservation. Tabu search turned out to be both computationally tractable and easily implementable for search problems of this kind. CONCLUSIONS: Opuntia conservation in México require the management of large areas of land for multiple uses. The multi-criteria analyses identified priority areas and organized them in large contiguous blocks that can be effectively managed. A high level of connectivity was established among the prioritized areas resulting in the enhancement of possible modes of plant dispersal as well as

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

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    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.

  16. 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

  17. 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.

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

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    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.

  19. 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

  20. 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.

    2014-01-01

    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.

  1. 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

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

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    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.

  3. Feather isotope analysis reveals differential patterns of habitat and resource use in populations of white-winged doves

    Science.gov (United States)

    Carleton, Scott A.; Martinez Del Rio, Carlos; Robinson, Timothy J.

    2015-01-01

    The white-winged dove (Zenaida asiatica) serves an important ecological role as a diurnal pollinator of the saguaro cactus in the Sonoran desert and an economic role as a highly sought after game bird in North America. White-winged doves are intimately linked to anthropogenic changes on the landscape and because of this, have experienced dramatic population fluctuations over the last 75 years in response, both positively and negatively, to anthropogenic changes on the landscape. To understand the factors driving population growth and decline of migratory species like the white-winged dove, it is imperative we study resource use on both their breeding and wintering grounds. To understand how populations are distributed on the wintering grounds, we tested an alternative to band recovery approaches by using stable isotope analysis. Before we could use isotope analysis to link breeding and wintering locations for this species, we first needed to determine if hydrogen (δ2H) and carbon (δ13C) stable isotopes in feather tissue (δ2Hf and δ13Cf, respectively) could differentiate among populations of white-winged doves across their breeding range in Texas, New Mexico, and Arizona. δ2Hf and δ13Cf not only differentiated between populations of white-winged doves that breed in the United States, but δ2Hf also provided further differentiation in white-winged doves that breed in native Sonoran Desert and agricultural habitats in the western portion of their range. Ecological processes associated with desert resources and anthropogenic influences, specifically saguaro cacti and irrigated crops, largely determined δ2Hf in some white-winged doves in Arizona whereas δ2H of precipitation (δ2Hp) largely determined δ2Hfof doves in New Mexico and Texas. This study highlights the usefulness of stable isotope analysis to differentiate populations of animals across the landscape and the insight isotopes can provide into habitat and resource use. Published 2015. This article

  4. Temperature in the seeds germination of pitaya genotypes

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    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.

  5. 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

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    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

  6. 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

  7. 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

  8. Biodiversity of Myxomycetes from the Monte Desert of Argentina

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    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

  9. 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

  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. 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

  12. 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.

  13. 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

  14. 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

  15. 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

  16. 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

  17. Guidebook of the Western United States: Part F - The Southern Pacific lines, New Orleans to Los Angeles

    Science.gov (United States)

    Darton, Nelson Horatio

    1933-01-01

    industries. Cacti become larger and more abundant, and many special trees and plants are prevalent, notably the mesquite; forests diminish in density, and far to the west trees occur only in the bottom lands. Agriculture here depends largely on irrigation, and the raising of cattle, sheep, and goats is the dominant industry. The principal underlying rocks are shale, soft sandstone, and chalk, which do not make strong relief but produce hills and ridges of moderate height separated by wide valleys, which along the larger streams are bordered by bottom lands. Northwest of San Antonio the Coastal Plain gives place rather abruptly to the Edwards Plateau, owing to the rapid rise of hard limestones; from San Antonio to Del Rio this feature lies north of the railroad but is visible at many places. For many miles west from Del Rio the railroad is on the plateau, which is floored by hard limestone and deeply trenched by the drainageways, notably by the canyons of the Devils River, the Rio Grande, and the Pecos River. In this district, where semiarid conditions prevail, vegetation is sparse and trees are mostly confined to valley bottoms except where the limestone supports a growth of juniper or live oak. The soil is thin, but it sustains grass and shrubs which afford good pasturage for many goats, sheep, and cattle. Owing to the gradual general rise of the strata to the west the land increases in elevation, and much of the plateau in south-central Texas is 2,000 feet above sea level in its eastern part and 3,000 feet in its western part. Near Sanderson this rise develops into the great dome of the Marathon uplift. The central part of this uplift is truncated, revealing a large area of closely folded Paleozoic rocks, making sharp ridges of the Appalachian type. The Edwards Plateau ends on the east side of this uplift. To the west is the Davis Mountain region, a wide province of volcanic rocks, characterized by rugged peaks and irregularly disposed ridges in great va

  18. 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

  19. 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