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The Mating Systems And Pollination Biology Of Three Species Of Verbena (Verbenaceae), Robert W. Cruden, Kristina K. Baker, Thomas E. Cullinan, Karen A. Disbrow, Kelly L. Douglas, John D. Erb, Kenneth J. Kirsten, Mary L. Malik, Elizabeth A. Turner, Jonathon A. Weier, Sherry R. Wilmot Jan 1990

The Mating Systems And Pollination Biology Of Three Species Of Verbena (Verbenaceae), Robert W. Cruden, Kristina K. Baker, Thomas E. Cullinan, Karen A. Disbrow, Kelly L. Douglas, John D. Erb, Kenneth J. Kirsten, Mary L. Malik, Elizabeth A. Turner, Jonathon A. Weier, Sherry R. Wilmot

Journal of the Iowa Academy of Science: JIAS

Because their flowers can be cross- and/or self-pollinated Verbena stricta, V hastata and V urticifolia are facultatively xenogamous. We suggest the flowers can be cross-pollinated because I) the fruit set of caged plants was substantially lower than that of open-pollinated plants, i.e. pollinators were necessary for typical fruit set and 2) the flowers of each species attracted a diverse array of hymenopteran, dipteran and lepidopteran pollinators that were capable of moving pollen between plants. Self-pollination was low due to the spatial separation of anthers and stigmas and/or an angled corolla that decreased the likelihood of pollen dropping from the anthers …


Eighty Years Of Research At Iowa Lakeside Laboratory: A Bibliography, Debby Zieglowsky Baker Jan 1990

Eighty Years Of Research At Iowa Lakeside Laboratory: A Bibliography, Debby Zieglowsky Baker

Journal of the Iowa Academy of Science: JIAS

Over 400 scientific reports and theses have resulted from work conducted at Iowa Lakeside Laboratory since it was founded in 1909. This bibliography updates Ulmer's 1962 bibliography and gathers some of the hundreds of theses written by students at the Lab.


Atmospheric Response To 1988 Drought Conditions And Future Climate Implications, Michael D. Mccorcle Jan 1990

Atmospheric Response To 1988 Drought Conditions And Future Climate Implications, Michael D. Mccorcle

Journal of the Iowa Academy of Science: JIAS

Plentiful precipitation in the central United States is one of the basic components of the successful agricultural industry in the Corn Belt. A combination of moisture, wind, and topographic factors creates an ideal condition for rainfall over most of the region during the late spring and early summer. In 1988, many ingredients necessary for wet weather were absent. The region experienced a drought unequalled since the 1930's. The drought of 1988 demonstrated chat the symptom of drought, namely, dry soils, can exacerbate and even perpetuate drought conditions by decreasing available moisture, altering circulation patterns vital to storm development, and increasing …


Impact Of Global Warming And Cooling On Midwestern Agriculture, Louis M. Thompson Jan 1990

Impact Of Global Warming And Cooling On Midwestern Agriculture, Louis M. Thompson

Journal of the Iowa Academy of Science: JIAS

The global warming since 1980 has been greater than it was during the warming trend from 1880 to 1940. This has caused concern that the very warm years of 1987 and 1988 might have been associated with greenhouse warming. However, the cooling trend from 1940 to 1980 occurred during a rapid buildup in greenhouse gases in the atmosphere. Although there may have been some greenhouse warming since 1880, the unusual warmth of 1987 and 1988 may have been caused by changes in the temperature of the equatorial Pacific Ocean, and changes in transparency of the atmosphere or ocher phenomena acting …


Population Estimates And Geographic Distribution Of The Yellow Mud Turtle (Kinosternon Flavescens) In Iowa, James L. Christiansen, Benny J. Gallaway, John W. Bickham Jan 1990

Population Estimates And Geographic Distribution Of The Yellow Mud Turtle (Kinosternon Flavescens) In Iowa, James L. Christiansen, Benny J. Gallaway, John W. Bickham

Journal of the Iowa Academy of Science: JIAS

The yellow mud turtle (Kinosternon flavescens) is an endangered species in Iowa known from six localities in the stare. The only large population is located on a private preserve on Big Sand Mound in Muscatine and Louisa Countries and is estimated to consist of 2,000 to 3,000 individuals. Following the removal of predators in 1979, density estimates have tripled as estimated by the Sequential Bayes Algorithm of mark-recapture data. Assuming the Big Sand Mound population was nor severely damaged by the drought of 1988, it is judged sufficiently large to serve as a source to enrich certain of Iowa's other …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1990

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Engineering Proteinase Inihibitor Genes For Plant Defense Against Predators, Clarence A. Ryan, Thomas Moloshok, Gregory Pearce, Gynhueng An, Robert W. Thornburg, Gerald Hall, Russell Johnson, Edward E. Farmer, Curtis Palm Jan 1990

Engineering Proteinase Inihibitor Genes For Plant Defense Against Predators, Clarence A. Ryan, Thomas Moloshok, Gregory Pearce, Gynhueng An, Robert W. Thornburg, Gerald Hall, Russell Johnson, Edward E. Farmer, Curtis Palm

Journal of the Iowa Academy of Science: JIAS

Small proteinaceous inhibitors (Mr<20,000) of the digestive serine proteinases of animals and microorganisms are found as moderately abundant proteins in storage organs and leaves of many plant genera. The proteins are powerful inhibitors of the digestive enzymes of plant predators and therefore are considered to be part of the array of defensive chemicals of plants. Proteinase inhibitor genes show excellent promise, using DNA technology, to manipulate plant genomes to express these biologically active proteins in order to improve natural defense systems. Members of two unrelated families of serine proteinase inhibitors found in tomato and potato plants, called Inhibitor I (monomer Mr 8000) and Inhibitor II (monomer Mr 12,300), are under both environmental and developmental regulation in different tissues of the plants. Genes coding for wound-inducible Inhibitors I and II have been isolated from both tomato and potato genomes and characterized. Tobacco plants have been transformed with the chimeric genes containing wound-inducible promoters fused with the reporter gene, chloramphenicol acetyl transferase, to assess promoter function and signal transmission. Transacting factors that regulate their expression in response to wounding are also being identified and purified. Intact genes are being employed to transform agriculturally important crop plants to determine their potential usefulness to enhance defensive capabilities of plants against herbivores and pathogens.


Radon Measurements In Houses In Eastern And Central Iowa, C. V. Weiffenbach, T. J. Hart Jan 1990

Radon Measurements In Houses In Eastern And Central Iowa, C. V. Weiffenbach, T. J. Hart

Journal of the Iowa Academy of Science: JIAS

Radon concentrations in air in main floor areas of 213 houses in Central and Eastern Iowa were measured with alpha track detectors integrating over periods of five months to one year. Forty-two houses in Central Iowa had significantly higher radon concentrations (lognormal distribution with geometric mean 2.1 pCi/L, geometric standard deviation 2.2, and arithmetic mean 2.75 pCi/L) than 171 houses studied in Eastern Iowa (geometric mean 1.6 pCi/L, geometric standard deviation 2.2, arithmetic mean 2.1 pCi/L). Significant differences in radon levels were found among different categories of houses with regard to ventilation rate, basement construction, and cracks and openings in …


Bibliography Of The Natural And Cultural History Of The Loess Hills Of Iowa, Dean M. Roosa, Darwin D. Koenig Jan 1990

Bibliography Of The Natural And Cultural History Of The Loess Hills Of Iowa, Dean M. Roosa, Darwin D. Koenig

Journal of the Iowa Academy of Science: JIAS

A bibliography of literature on Iowa's Loess Hills includes references containing information on the cultural or natural history of chis western Iowa landform region. The bibliography is divided into six parts: general, archaeological, botanical, geological, historical, and zoological. Annotations are included only where necessary to clarify contents. Because of their rugged topography, the Loess Hills of western Iowa have resisted large-scale conversion to agriculture. This has permitted noteworthy persistence of native prairies and woodlands, along with their associated species. This bibliography complements two special issues of the Proceedings of the Iowa Academy of Science devoted to Iowa's Loess Hills.


Back Cover Jan 1990

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Cover - Table Of Contents Jan 1990

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Journal Of The Iowa Academy Of Science Submission Form And Instruction Sheet Jan 1990

Journal Of The Iowa Academy Of Science Submission Form And Instruction Sheet

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Climate Change And The Potential Impact On The Soil Resource, J. L. Hatfield Jan 1990

Climate Change And The Potential Impact On The Soil Resource, J. L. Hatfield

Journal of the Iowa Academy of Science: JIAS

Climatic change will lead to changes in the carbon dioxide C02, temperature, and precipitation. There have been many predictions of the effect of climatic change on plant growth but none on the soil parameters or water use. To fully understand the implications on soil management from climate change the expected changes in soil temperature, water use, and water and nutrient use efficiency need quantification.


Richard Bovbjerg And The Iowa Lakeside Laboratory, Michael J. Lannoo Jan 1990

Richard Bovbjerg And The Iowa Lakeside Laboratory, Michael J. Lannoo

Journal of the Iowa Academy of Science: JIAS

In the spring of 1977, in Ames, a struggling biology major who had earlier shown some promise was ordered by his advisor: "Go to Lakeside Lab and take Dick Bovbjerg's Aquatic Ecology course." I did and it worked. I've parlayed that early potential into a career. And like so many others I return to Lakeside, the first time to take another course, then to do my Master's research. More recently I come back to teach the Field Vertebrate Zoology course. Likewise, Dick has shifted from mentor to colleague, and we've co-authored a paper (Lannoo and Bovbjerg, 1985). Now, I am …


The Effect Of Harvesting On Macrophyte Regrowth And Water Quality In Ladue Reservoir, Ohio, G. Dennis Cooke, Angela B. Martin, Robert E. Carlson Jan 1990

The Effect Of Harvesting On Macrophyte Regrowth And Water Quality In Ladue Reservoir, Ohio, G. Dennis Cooke, Angela B. Martin, Robert E. Carlson

Journal of the Iowa Academy of Science: JIAS

Two experiments in a bay of LaDue Reservoir (Geauga Co., northeastern Ohio) during summer, 1985 demonstrated that removal of Eurasian watermilfoil (Myriophyllum spicatum L.) root crowns with an aquatic weed harvester retarded plant regrowth to quantities well below nuisance levels for 28 days. Nearly summer-long control was achieved following a "touch-up" harvest on day 42. In contrast, the harvester was used in this bay in 1982 to "mow" milfoil, leaving intact "stumps." The mowed plants regrew to preharvest and control area biomass levels within 23 days. The difference in plant regrowth between these two methods strongly suggests that user dissatisfaction …


An Interpretation Of Hustedt's Terms "Schattenlinie", "Perlenreihe" And "Hocker" Using Specimens Of The Cyclotella Radiosa-Complex, C. Distinguenda, Hust., And C. Cyclopuncta Nov. Sp., Hannelore Hakansson, John R. Carter Jan 1990

An Interpretation Of Hustedt's Terms "Schattenlinie", "Perlenreihe" And "Hocker" Using Specimens Of The Cyclotella Radiosa-Complex, C. Distinguenda, Hust., And C. Cyclopuncta Nov. Sp., Hannelore Hakansson, John R. Carter

Journal of the Iowa Academy of Science: JIAS

With the help of light- and scanning electron micrographs HUSTEDT'S terms "Schattenlinie", "Perlenrcihe", and "Hocker" are explained using specimens in the Cydotella radiosa complex, and C. distinguenda HUST. The complicated history of C. operculata (AG.) KUTZ., published elsewhere, has shown that C. distinguenda HUST. is the correct name to be used for this taxon. In this connection the new nomenclatural combination C. distinguenda var. unipunctata nov. comb. is proposed.

Morphological differences are discussed and the possibility of different "unipunctata" species is shown. Distinct morphological features found indicate the necessiry to describe a new species: C. cyclopuncta nov. sp. rather than …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1990

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Cover - Table Of Contents Jan 1990

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1990

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Anatomical Characterization Of Western Corn Rootworm Damage In Adventitious Roots Of Maize, Walter E. Riedell, Alice Y. Kim Jan 1990

Anatomical Characterization Of Western Corn Rootworm Damage In Adventitious Roots Of Maize, Walter E. Riedell, Alice Y. Kim

Journal of the Iowa Academy of Science: JIAS

Corn rootworms are one of the most economically damaging insect pests of maize, yet little is known about the feeding behavior of the larvae. This study was conducted to determine which tissues of the adventitious roots of maize are damaged by western corn rootworm (Diabrotica virgifera virgifera LeConte) larval feeding. Root axes (10 cm long) were removed from the fifth node of greenhouse-grown maize plants. Root segments 2 cm long, excised 4 or 6 cm from the root tip, were infested with second or third stage larvae, respectively, (0, 1, 3, or 6 larvae per segment) for a period of …


Correlation Of Raccoon Pelt Qualities With Age, Sex, And Physical Condition, Travis C. Glenn Jan 1990

Correlation Of Raccoon Pelt Qualities With Age, Sex, And Physical Condition, Travis C. Glenn

Journal of the Iowa Academy of Science: JIAS

Fur harvesters and fur buyers have many intuitive ideas about how raccoons' pelt qualities differ due to age, sex, or physical condition. We tried to demonstrate correlations between age classes (juvenile and adult), sex, and physical condition and the quality of raccoon pelts. Quality of pelts was described in three objective ways: size of the pelt, density of the pelage (primeness), and color of the pelage. Physical condition was measured by kidney fat index (KFI) and skin fat index (SFI). Size of the pelts was correlated with age, sex, and both measures of physical condition. Primeness of the pelts was …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1990

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1990

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Rare Iowa Plant Notes From The R. V. Drexler Herbarium, Jeffery C. Nekola Jan 1990

Rare Iowa Plant Notes From The R. V. Drexler Herbarium, Jeffery C. Nekola

Journal of the Iowa Academy of Science: JIAS

Notes on the distribution, habitats, associated species, and taxonomic considerations for 134 rare Iowa plants are presented. These taxa, including 15 Pteridophytes, 74 Dicots, and 45 Monocots were located during a decade of field research (1979-1989) concentrated in eastern, northeastern, and northwestern Iowa. Included among these are 10 taxa previously unrecorded from the Iowa flora (Carex sterilis, Circaea X intermedia, Cypripedium calceolus var. parviflorum, Lycopodium inundatum, Opuntia macrorhiza, Salix candida X Salix rigida, Salix X clarkei, Solidago uliginosa, Spiranthes ova/is, Viola adunca), and 15 taxa (Angelica atropurpurea, Aristolochia serpentaria, Artemesia frigida, Aster linariifolius, Berula pusilla, Carex conoidea, Eleocharis pauciflora var. …


Back Cover Jan 1990

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Cover - Table Of Contents Jan 1990

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1990

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Climate Trends In Iowa, Richard E. Carlson Jan 1990

Climate Trends In Iowa, Richard E. Carlson

Journal of the Iowa Academy of Science: JIAS

Long-term trends for various weather elements are presented for the period 1900-1988. Summer and winter season, and annual air temperature patterns are statistically weak because of large inrerannual variability, but trends are evident. There was a general warming from 1900 until the 40's, with a leveling or slight cooling following. Since the mid-70's, a warming trend seems to be taking place, but this cannot be confirmed. Spring season air temperatures showed no trend except that the most recent 4 years (1985-1988) were decidedly warmer than normal. Winter season air temperatures showed a change in trend in the 30's, but the …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1990

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1990

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.