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Full-Text Articles in Life Sciences

Helminths Of The Southwestern Toad, Bufo Microscaphus, Woodhouse's Toad, Bufo Woodhousii (Bufonidae), And Their Hybrids From Central Arizona, Stephen R. Goldberg, Charles R. Bursey, Keith B. Malmos, Brian K. Sullivan, Hay Cheam Nov 1996

Helminths Of The Southwestern Toad, Bufo Microscaphus, Woodhouse's Toad, Bufo Woodhousii (Bufonidae), And Their Hybrids From Central Arizona, Stephen R. Goldberg, Charles R. Bursey, Keith B. Malmos, Brian K. Sullivan, Hay Cheam

Great Basin Naturalist

The gastrointestinal tracts, lungs, and urinary bladders from 77 Bufo microscaphus, 61 Bufo woodhousii, and 8 of their hybrids were examined for helminths. One species of trematode (Glypthelmins quieta), 1 species of cestode (Distoichometra bufonis), and 5 species of nematodes (Aplectana incerta, A. itzocanensis, Rhabdias americanus, Physaloptera sp., and Physocephalus sp.) were found. The greatest prevalence (41%) and mean intensity (231.7) were recorded for Aplectana incerta in Bufo woodhousii. It appears hybrids harbor fewer parasites than either parent species.


Effects Of Douglas-Fir Foliage Age Class On Western Spruce Budworm Oviposition Choice And Larval Performance, Kimberly A. Dodds, Karen M. Clancy, Kathryn J. Leyva, David Greenberg, Peter W. Price Apr 1996

Effects Of Douglas-Fir Foliage Age Class On Western Spruce Budworm Oviposition Choice And Larval Performance, Kimberly A. Dodds, Karen M. Clancy, Kathryn J. Leyva, David Greenberg, Peter W. Price

Great Basin Naturalist

The western spruce budworm (Choristoneura occidentalis Freeman) prefers to feed on flushing buds and current-year needles of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco). Budworm larvae will not typically consume older age classes of needles unless all current-year foliage is depleted. We tested the following null hypotheses: (1) budworm larvae can feed on foliage with a wide range of qualities (i.e., current 1-, 2-, or 3-year-old needles) without measurable effects on fitness; and (2) budworm adults do not show any oviposition preference linked to the age of the foliage they fed on as larvae. We used both laboratory and field …


Selecting Wilderness Areas To Conserve Utah's Biological Diversity, Diane W. Davidson, William D. Newmark, Jack W. Sites Jr., Dennis K. Shiozawa, Eric A. Rickart, Kimball T. Harper, Robert B. Keiter Apr 1996

Selecting Wilderness Areas To Conserve Utah's Biological Diversity, Diane W. Davidson, William D. Newmark, Jack W. Sites Jr., Dennis K. Shiozawa, Eric A. Rickart, Kimball T. Harper, Robert B. Keiter

Great Basin Naturalist

Congress is currently evaluating the wilderness status of Bureau of Land Management (BLM) public lands in Utah. Wilderness areas play many important roles, and one critical role is the conservation of biological diversity. We propose that objectives for conserving biodiversity on BLM lands in Utah be to (1) ensure the long-term population viability of native animal and plant species, (2) maintain the critical ecological and evolutionary processes upon which these species depend, and (3) preserve the full range of communities, successional stages, and environmental gradients. To achieve these objectives, wilderness areas should be selected so as to protect large, contiguous …


Oochoristica Scelopori (Cestoda: Linstowiidae) In A Grassland Population Of The Bunch Grass Lizard, Sceloporus Scalaris (Phrynosomatidae), From Arizona, Stephen R. Goldberg, Charles R. Bursey, Chris T. Mcallister, Hobart M. Smith, Quynh A. Truong Apr 1996

Oochoristica Scelopori (Cestoda: Linstowiidae) In A Grassland Population Of The Bunch Grass Lizard, Sceloporus Scalaris (Phrynosomatidae), From Arizona, Stephen R. Goldberg, Charles R. Bursey, Chris T. Mcallister, Hobart M. Smith, Quynh A. Truong

Great Basin Naturalist

No abstract provided.


Wood And Stem Anatomy Of Menispermaceae, Sherwin Carlquist Jan 1996

Wood And Stem Anatomy Of Menispermaceae, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

Qualitative and quantitative data are presented for 17 collections of 15 species representing 14 genera. One species is a shrub (Cocculus laurifolius), one a subshrub (C. trilobus), and the remainder are lianas. Successive cambia are analyzed with respect to ontogeny and histology of products. Whether any Menispermaceae may or may not plesiomorphically lack successive cambia would require a more extensive survey of the family. Apomorphic absence of successive cambia is likely for species with subshrub growth forms (Cocculus trilobus, Menispermum canadense L.). Lianoid Menispermaceae share the following features: successive cambia, wide vessels, wide rays, …


Patterns Of Dilatation Growth In Ficus Pumila And Ficus Sycomorus, Simcha Lev-Yadun Jan 1996

Patterns Of Dilatation Growth In Ficus Pumila And Ficus Sycomorus, Simcha Lev-Yadun

Aliso: A Journal of Systematic and Floristic Botany

Dilatation growth occurs in the secondary phloem rays, in the axial secondary phloem parenchyma, and in the parenchyma of the cortex of Ficus pumila (a Iiana) and Ficus sycomorus (a tree). Dilatation growth in Ficus pumila is mostly the result of meristematic activity, but in Ficus sycomorus it is the result of both meristematic activity and increase in cell size. Dilatation meristem is formed in the rays in various patterns: in the center of the ray, at one or two of the ray's margins, in horizontal or diagonal strips (relative to the axis) in the ray, or in more than …


Studies In Macrosiphonia (Apocynaceae): Generic Recognition Of Telosiphonia, James Henrickson Jan 1996

Studies In Macrosiphonia (Apocynaceae): Generic Recognition Of Telosiphonia, James Henrickson

Aliso: A Journal of Systematic and Floristic Botany

Woodson recognized two subgenera within Macrosiphonia (Apocynaceae: Apocynoideae), a South American subgenus Eumacrosiphonia, and a North American subgenus Telosiphonia each with five species. Both taxa are characterized by low subshrub-shrub, nonviny growth habits, white, long-tubed, vespertine corollas of a type associated with moth pollination. Their distinctive anther and style-tip characteristics show each is related to a group of genera around Mandevilla and Mesechites. The two subgenera, however, differ strongly from each other in inflorescence, style-head structure, and pollen size indicating that they are not sister taxa and that Macrosiphonia as currently recognized is polyphyletic. Thus the subgenus Telosiphonia …


Baccharis Malibuensis (Asteraceae): A New Species From The Santa Monica Mountains, California, R. Mitchell Beauchamp, James Henrickson Jan 1996

Baccharis Malibuensis (Asteraceae): A New Species From The Santa Monica Mountains, California, R. Mitchell Beauchamp, James Henrickson

Aliso: A Journal of Systematic and Floristic Botany

Baccharis malibuensis is described from the Malibu Lake region of the Santa Monica Mountains, Los Angeles County, California. It is closely related to Baccharis plummerae subsp. plummerae but differs in having narrow, subentire, typically conduplicate, sparsely villous to mostly glabrous leaves with glands occurring in depressions on the adaxial surface, more cylindrical inflorescences, and a distribution in open chaparral vegetation. The new taxon shares some characteristics with B. plummerae subsp. glabrata of northwestern San Luis Obispo County, e.g., smaller leaves, reduced vestiture, and occurrence in scrub habitat, but the two taxa appear to have developed independently from B. p. subsp. …


Population Structuring And Patterns Of Morphological Variation In Californian Styrax (Styracaceae), Peter Fritsch Jan 1996

Population Structuring And Patterns Of Morphological Variation In Californian Styrax (Styracaceae), Peter Fritsch

Aliso: A Journal of Systematic and Floristic Botany

Recent studies of genetic variation within and among populations and phylogenetic estimates have provided evidence bearing on the evolutionary history and taxonomy of Styrax in California (S. redivivus). In this paper, data from these studies are further analyzed and integrated with new data from morphology to gain insight into the nature and taxonomic significance of character variation within this species. Six morphological characters thought to be important in the delimitation of infraspecific taxa within S. redivivus were measured on 52 herbarium specimens and analyzed with Pearson correlations and multivariate methods. Five characters are significantly associated with latitude and …


A Revision Of The Euphorbia Dioscoreoides Complex (Euphorbiaceae), Victor W. Steinmann Jan 1996

A Revision Of The Euphorbia Dioscoreoides Complex (Euphorbiaceae), Victor W. Steinmann

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Using Confocal Microscopy In The Study Of Plant Structure And Development, Mark P. Running, Elliot M. Meyerowitz Jan 1996

Using Confocal Microscopy In The Study Of Plant Structure And Development, Mark P. Running, Elliot M. Meyerowitz

Aliso: A Journal of Systematic and Floristic Botany

The widespread application of confocal laser scanning microscopy has revolutionized biological imaging. We have developed a protocol for using confocal microscopy to examine the development of wild type and mutant Arabidopsis thaliana, overcoming the technical difficulties associated with examining whole-mounted plant tissue. This allowed us to rapidly determine the underlying cellular defects that lead to the morphological changes visible in several mutants, and has led to a greater understanding of the mechanisms involved in the control of floral organ number.


Genetic Dissection Of The Morphological Evolution Of Maize, John Doebley Jan 1996

Genetic Dissection Of The Morphological Evolution Of Maize, John Doebley

Aliso: A Journal of Systematic and Floristic Botany

Maize (Zea mays ssp. mays) and its wild progenitor, teosinte (Z. mays ssp. parviglumis) differ dramatically in inflorescence and plant architecture despite the fact that their evolutionary divergence occurred within the past 10,000 years or less. To elucidate the genetic control of the morphological differences between maize and teosinte, my colleague and I employed quantitative trait locus mapping with molecular markers. Results indicated that most of the variation in plant and inflorescence morphology between maize and teosinte can be explained by five restricted regions of the genome. In this paper, characterization of three of these regions …


Crossroads, Milestones, Amd Landmarks In Insect Development And Evolution: Implications For Systematics, Rob Desalle, Donat Agosti, Michael Whiting, Beatriz Perez-Sweeney, James Remsen, Rick Baker, James Bonacum, Ranhy Bang Jan 1996

Crossroads, Milestones, Amd Landmarks In Insect Development And Evolution: Implications For Systematics, Rob Desalle, Donat Agosti, Michael Whiting, Beatriz Perez-Sweeney, James Remsen, Rick Baker, James Bonacum, Ranhy Bang

Aliso: A Journal of Systematic and Floristic Botany

Our understanding of insect development and evolution has increased greatly due to recent advances in the comparative developmental approach. Modem developmental biology techniques such as in situ hybridization and molecular analysis of developmentally important genes and gene families have greatly facilitated these advances. The role of the comparative developmental approach in insect systematics is explored in this paper and we suggest two important applications of the approach to insect systematics--character dissection and morphologicallandmarking. Exi~ng morphological characters can be dissected into their genetic and molecular components in some cases and this will lead to more and richer character information in systematic …


Bouteloua Chihuahuana (Gramineae), A New Nomenclatural Combination, J. Travis Columbus Jan 1996

Bouteloua Chihuahuana (Gramineae), A New Nomenclatural Combination, J. Travis Columbus

Aliso: A Journal of Systematic and Floristic Botany

A revision of the Euphorbia dioscoreoides complex (subgenus Agaloma) is provided. Euphorbia dioscoreoides ssp. attenuata and E. eglandulosa, both from Mexico, are proposed as new; E. digitata is reduced to synonymy under E. subpeltata. Representative specimens are cited, and distributional and ecological data are provided.


Diversity And Evolution Of Seedling Baupläne In Perlargonium (Geraniaceae), Cynthia S. Jones, Robert A. Price Jan 1996

Diversity And Evolution Of Seedling Baupläne In Perlargonium (Geraniaceae), Cynthia S. Jones, Robert A. Price

Aliso: A Journal of Systematic and Floristic Botany

The genus Pelargonium (Geraniaceae) exhibits tremendous variation in growth form. We apply a broadly defined concept of Bauplan in our study of growth form, architectural and anatomical features of early seedling development in the type subgenus. We analyze variation in these features within a phylogenetic framework based on sequence comparisons of internal transcribed spacer regions (ITS) of nuclear ribosomal DNA.

Preliminary ITS sequence comparisons show strong support for two major clades. One major clade contains two subgroups, one consisting of three previously recognized sections of more or less woody shrubs and subshrubs (sections Pelargonium, Glaucophyllum and Campylia), and …


Promising Pasture Plants From Overseas, John Lawson Jan 1996

Promising Pasture Plants From Overseas, John Lawson

Journal of the Department of Agriculture, Western Australia, Series 4

Farmers from Northampton to Albany were among the 00 visitors to a spring field day at Agriculture Western Austrslis's Medina Research Station, where they saw a collection of promising new and different pasture legumes. These were the products of a highly succesful selection and breeding program based mainly on material collected overseas.

John Lawson highlights the overseas collection aspects of an exciting and rewarding program.


Weeds Can Poison Crops, Aik Hock Cheam Jan 1996

Weeds Can Poison Crops, Aik Hock Cheam

Journal of the Department of Agriculture, Western Australia, Series 4

Weeds can interfere with the growth of a crop simply by competing with the crop for nutrients, moisture and light. But some weeds also release chemicals that inhibit the germination and growth of crop plants; the technical term for this is allelopathy. Aik Cheam outlines the problems caused by two common weeds and the discusses preventative measures.


Does The Monocot Mode Of Leaf Development Characterize All Monocots?, Geeta Bharathan Jan 1996

Does The Monocot Mode Of Leaf Development Characterize All Monocots?, Geeta Bharathan

Aliso: A Journal of Systematic and Floristic Botany

Patterns of early leaf development in monocots are analyzed in a phylogenetic context. Recent developmental and phylogenetic studies enable this reevaluation of the leaf base model of the developing monocot leaf. Two questions are addressed: a) is the presence of the Vorläuferspitze (fore-runner tip) invariably correlated with development of the lamina from the lower leaf zone? and b) was the ancestral monocot characterized by the leaf base mode of development? Scanning electron microscopic observations are made of young primorida using the mold and cast method. These data are combined with data from the literature and examined in a phylogenetic context …


Integrating Cellular And Molecular Approchaes Into Studies Of Development And Evolution: The Issue Of Morphological Homology, Andrés Collazo, Scott E. Fraser Jan 1996

Integrating Cellular And Molecular Approchaes Into Studies Of Development And Evolution: The Issue Of Morphological Homology, Andrés Collazo, Scott E. Fraser

Aliso: A Journal of Systematic and Floristic Botany

Understanding the development and evolution of complex morphological characters requires broad, multidisciplinary approaches. By combining biological imaging, phylogenetic analyses, embryological manipulations and additional modem molecular techniques (e.g., whole mount in situ hybridization), we can address fundamental questions, such as the determination of homology. Many of the novel structures that evolved in vertebrates and distinguish them from their ancestors (such as jaws and the mechanosensory lateral line) are derived embryonically from two migratory ectodermal tissues, neural crest and/or various epidermal placodes. In particular, time-lapse cinematography of fluorescently labeled cells in living Xenopus and fish embryos has proved a powerful technique, revealing …


Introduction To The Symposium: "The New Morphology: Potential For Integrating New Techniques And Concepts", Elizabeth Zimmer Jan 1996

Introduction To The Symposium: "The New Morphology: Potential For Integrating New Techniques And Concepts", Elizabeth Zimmer

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Peltandra Virginica (L.) Schott & Endl. (Arrow Arum), A New Species And Genus For Minnesota, Charles Argue Jan 1996

Peltandra Virginica (L.) Schott & Endl. (Arrow Arum), A New Species And Genus For Minnesota, Charles Argue

Journal of the Minnesota Academy of Science

Peltandra virginica is reported as a new addition to the flora of Minnesota. Found in Cook County in the northeasternmost part of the state, it is separated by about 400 km from the closest previously reported location for this species on Michigan's upper peninsula.


Partial Characterization Of Bacteriophages Of Pseudomonas Syringae Pv.Tomato, Scott M. Minor, Russell O. Nordeen, Chad E. Paschall Jan 1996

Partial Characterization Of Bacteriophages Of Pseudomonas Syringae Pv.Tomato, Scott M. Minor, Russell O. Nordeen, Chad E. Paschall

Journal of the Arkansas Academy of Science

No abstract provided.


Plantain Sunflower (Helianthus Occidentalis Subsp. Plantagineus) In Arkansas, Daniel L. Marsh, Timothy A. Golden Jan 1996

Plantain Sunflower (Helianthus Occidentalis Subsp. Plantagineus) In Arkansas, Daniel L. Marsh, Timothy A. Golden

Journal of the Arkansas Academy of Science

No abstract provided.


Options For Pest Management In Pastures, Phil Michael, Mike Grimm, Mike Hyder, Peter Doyle Jan 1996

Options For Pest Management In Pastures, Phil Michael, Mike Grimm, Mike Hyder, Peter Doyle

Journal of the Department of Agriculture, Western Australia, Series 4

Redlegged eath mit, blue oat ite, lucern flea and aphids damage pastures across southern Australia, and it has been estimated that they cause annual losses to the Australian wool industry alone of over $200 million.

Redlegged earth mite is without doubt the most serious of the four pests. Peter DoPhil Michael, Mike Grimm, Mike Hyder and Peter Doyle discuss intergrated management options to control these pests.


Positive Price Outlook For Wheat : Implications For Wa Agriculture, Alan Haagensen, Ian Wilkinson Jan 1996

Positive Price Outlook For Wheat : Implications For Wa Agriculture, Alan Haagensen, Ian Wilkinson

Journal of the Department of Agriculture, Western Australia, Series 4

After a 40 year period over which wheat prices have dropped by an average of 2.7 per cent annually in real terms, fundamental changes in wheat supply and demand look set to reverse this trend. It is possible that real prices could increase by as much as 4 per cent anually in the medium term.

Alan Haagensen and Ian Wilkinson look at the forecasts for wheat prices and outline the forces that will influence world supply and demands for wheat.


Skeleton Weed : The Current Situation, Peter Scott, Jon Dodd Jan 1996

Skeleton Weed : The Current Situation, Peter Scott, Jon Dodd

Journal of the Department of Agriculture, Western Australia, Series 4

Skeleton weed is a major threat to western Australia's grain industry. This weed established itself throughout the entire eastern States wheatbelt in just over 50 years and is now found from south-east Queensland to South Australia. It was first founs in Western Australia at Ballidu in 1963, and since that time has been the subject of an ongoing and intensive eradication campaign. Peter Scott and Jon Dodd report on the present status of skeleton weed in Western Australia and outline the progress to date and future directions of the eradication campaign.


Western Flower Thrips, David Cook, Ian Dadour, Ernie Steiner, Brett Scourse Jan 1996

Western Flower Thrips, David Cook, Ian Dadour, Ernie Steiner, Brett Scourse

Journal of the Department of Agriculture, Western Australia, Series 4

Western flower thrips (Franklinislla occidentalis Pergands) is a serious pest of floral and vegetable crops. From its original habitat in western USA it has now spread throughout North America, Mexico, New Zealand and Europe. David Cook, Ian Dadour, Ernis Steiner and Brett Scourse outline its biology and the control options available.


Tomato Spotted Wilt Virus And Its Management, Lindrea Latham, Roger Jones Jan 1996

Tomato Spotted Wilt Virus And Its Management, Lindrea Latham, Roger Jones

Journal of the Department of Agriculture, Western Australia, Series 4

In 1993, western flower thrips, an important pest of horticultural crops, was found in Western Australia. Since then there has been an upsurge in damsging virus disease epidemics caused by tomato spotter wilt virus in horticultural crops. This has occurred because western flower thrips is a more effective vector of tomato spotted wilt virus than other thrips species. Lindrea Latham and Roger Jones outline the symptoms, spread and management of this serious virus disease in vegetables and ornamentals.


Improving Dairy Farm Performance, Ruth Dilley Jan 1996

Improving Dairy Farm Performance, Ruth Dilley

Journal of the Department of Agriculture, Western Australia, Series 4

Western Austraian sairy farmers produce more milk per cow and per farm than their eastern Sttates counterparts and the milk is also of higher quality. But there is always room for improvement and as grain prices rise it is crucial that maximum benefit is derived from the cheapest feed source - the pasture.With this in mind Ruth Dilley looks at the Dairy Farm Performance Program - a comprihensive farm database developed by Agriculture Western Australia.


Weeds : A Curse For Native Plants In Farm Woodlands, Max Abensperg-Traun Jan 1996

Weeds : A Curse For Native Plants In Farm Woodlands, Max Abensperg-Traun

Journal of the Department of Agriculture, Western Australia, Series 4

Weeds have a mJOR IMPct on native Australian plants, particularly in the tropical north and the agricultural regions of southern Australia.

Maz Abensperg-Traun, and his clooeagues from the CSIRO Division of Wildlife and Ecology, explainthe effects of weed invasion on the diversity of native herbaceous plants in faarm woodlands in the centeral wheatbelt of south-west Western Australia.