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Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Area-Dependent Changes In Bird Densities In Iowa Marshes, Mike Brown, James J. Dinsmore

Journal of the Iowa Academy of Science: JIAS

Species richness and density of Iowa marsh birds were positively correlated with marsh area, but area accounted for 69% of the variation in species richness and only 19% of the variation in density. Although densities of five of nine species examined correlated with marsh area, total density was not significantly correlated with area when the effects of species richness were eliminated. Area was the most frequent significant variable in regression equations for species richness, total density, and the densities of nine individual species on six variables. Unlike species-area relationships, density-area relationships are relatively weak, and knowledge of other ecological factors …

Index For Volume 98

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Part Ii - Regular Issue

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Hormonal Regulation Of Gene Expression M The Aleurone Layers Of Cereal Grains, Tuan-Hua David Ho

Journal of the Iowa Academy of Science: JIAS

The aleurone layers of cereal grains offer a convenient system for studies of the molecular action of two plant hormones, gibberellins (GA) and abscisic acid (ABA). Gibberellins induce the synthesis of ix-amylase and several other hydrolytice enzymes. The action of GA is essentially at the transcriptional level, it enhances the level of steady-state levels of ix-amylase mRNAs, the rate of transcription of ᴕ-amylase genes and the activity of a trans-acting factor which interacts with specific regions of ix-amylase genes. Abscisic acid antagonizes the effect of GA by inhibiting the induction of hydrolytic enzymes, yet the effect of ABA itself is …

Estimates Of Quantitative Genetic Parameters M Iap2b(M) Random-Mating Sorghum Population, A. J. Maves, R. E. Atkins

Journal of the Iowa Academy of Science: JIAS

Random-mating populations of sorghum [Sorghum bicolor (L.) Moench] are used extensively as germ plasm in the development of parental lines for hybrids. Populations improved by recurrent selection provide a useful source for the selection of superior parental lines. Our objective was to determine the effectiveness of mass selection for threshed-panicle weight by comparing the performance of lines (S₁ families) chosen randomly from CO and C4 of sorghum population IAP2B. Sixty S₁ families from each cycle were grown in five Iowa environments.

Four cycles of selection for panicle weight shifted the mean for grain yield favorably, and the range …

A Study Of Sphacelotheca Occidentalis, Cause Of Kernel Smut Of Big Bluestem, Karen M. Snetselaar, Lois H. Tiffany

Journal of the Iowa Academy of Science: JIAS

Sphacelotheca occidentalis causes kernel smut disease of Andropogon gerardii, a prairie grass. The smut fungus is systemic, perennial, causes severe stunting, and sporulates in florets. Spores develop in gall-like sari composed of grass and fungal cells. Spores initiate in a meristematic area near the base of the sorus, and progressively more mature spores are found toward the sorus rip. The cylindrical sari have a central columella of host vascular tissue permeated by hyphae, sporogenous hyphae and developing teliospores that surround the columella, and a peridium of host and fungal cells. Sporogenous hyphae ramify in a gelatinous matrix that disappears as …

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Radon In Iowa Homes: Results Of Screening Measurements, Laurent Hodges, Lynne Gillette

Journal of the Iowa Academy of Science: JIAS

Homeowner-initiated short-term radon screening measurements in Iowa homes show that only about 30% of the homes have low enough radon levels - below 148 Bq/m (4.0 pC1/L) - that no follow-up measurements are necessary. Over 6 percent of the homes have screening measurements in excess of 740 Bq/m³ (20 pCi/L), a level at which prompt follow-up measurements are recommended. In all parts of the state, the range of radon results extends from low levels (below 37 Bq/m³ = 1 pCi/L) to high levels (above 740 Bq/m³). The average radon results tend to be higher than the …

Annual Report Of The Iowa Academy Of Science, 1989-90, Paul E. Rider

Journal of the Iowa Academy of Science: JIAS

Starting in 1976, annual reports have served as a continuing record of the activities of the Iowa Academy of Science. These augment a 100 year history of the Academy which was written in the centennial year of 1975.

This report covers the period from July 1, 1989 to June 30, 1990. It is based on the official records of the Academy (committee reports, Board minutes, correspondence) as well as the recollections, impressions and musings of the author.

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

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

An Annotated Checklist Of The Vascular Plant Flora Of Guthrie County, Iowa, Dean M. Roosa, Lawrence J. Eilers, Scott Zager

Journal of the Iowa Academy of Science: JIAS

The known vascular plant flora of Guthrie County, Iowa, based on field, herbarium, and literature studies, consists of 748 taxa (species, varieties, and hybrids), 135 of which are naturalized. Species which appear on the state's list of endangered and threatened species, or are otherwise rare, are discussed.

There is an affinity of the plants of Guthrie County with those of the Ozark plateau, and with specialized habitats providing extensions of ranges for species normally found farther north or east.

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Part I - Papers Presented At The 1989 Plant Science Lecture Series

Journal of the Iowa Academy of Science: JIAS

The first six titles in this issue of the Journal of Iowa Academy of Science are papers presented at the 1989 edition of the Plant Science Lecture Series held annually at Iowa State University. This lecture series focuses each year on some aspect of plant biology, and each series is composed of six to eight seminars related to a theme that is selected to be timely and related to improvement of field, forage, forest and horticultural crops.

In Search Of A Gibberellin Receptor, Lalit M. Srivastava, Konrad A. Sechley

Journal of the Iowa Academy of Science: JIAS

Use of tritiated gibberellins ([³H] GA₁, [³H] GA₄) of high specific activity and purity has allowed the determination of GA-specific binding sites in several plant tissues both in vivo and in vitro. In cucumber hypocotyls and pea epicotyls which have been most investigated the binding of [³H] GA; occurs to soluble proteins. This binding is saturable ('n' =about 30 pmol. Mg^-1 soluble protein), of high affinity (K_D= about 70 nM), and is competed for by other GA, and derivatives in proportion to their biological activity in these …

Auxin-Regulated Gene Expression, Tom J. Guilfoyle

Journal of the Iowa Academy of Science: JIAS

A number of cDNA clones to independent mRNAs that increase in amount after brief exposure to auxins have been isolated. From soybean, sequenced, and characterized. Increases in mRNA abundance can be detected as early as 2.5 minutes after auxin application to excised elongating regions of soybean hypocotyls. Increased transcription rates on the genes which encode the auxin-responsive mRNAs account, at least partly, for the accumulation of mRNAs. A variety of auxins induce the accumulation of the mRNAs, but other plant hormones have no effect on the mRNA abundance. Some of the genes which encode the mRNAs are clustered in the …

Regulation Of Phytochrome Gene Expression, J. T. Colbert, S. A. Costigan, P. Avissar, Z. Zhao

Journal of the Iowa Academy of Science: JIAS

In etiolated oat seedlings exposure to red light results in a decrease in the transcription of the phytochrome genes, the abundance of phytochrome mRNA, and the level of phytochrome protein. Phytochrome itself serves as the photoreceptor for the response of decreased mRNA and transcription levels. The decrease in phytochrome mRNA is sensitive to low levels of Pfr. Even green "safelight" is capable of inducing a decrease in phytochrome mRNA abundance. Barley phytochrome mRNA abundance is also dramatically down-regulated in response to red light but other plant species vary in their ability to decrease phytochrome mRNA abundance after red light treatment. …

The Axr1 Mutation Of Arabidopsis Is Expressed 10 Booth Roots And Shoots, Cythia Lincoln, Mark Estelle

Journal of the Iowa Academy of Science: JIAS

In order to identify genes involved in auxin action we have isolated a number of mutants of Arabidopsis thaliana which are resistant co exogenous application of either indole-3-acetic acid or 2, 4-dichlorophenoxyacecic acid. One of the genes identified in chis way is the Axr1 gene. Recessive mutations in this gene confer resistance co auxin as well as a number of morphological defects. In this report we describe the isolation of at least two new axr1 alleles. In addition, we show that the axr1 mutation affects gravitropic growth of the root, auxin-induced ethylene biosynthesis and growth in tissue culture. Our results …

Stimulus Response Coupling In Auxin Action, K. R. Libbenga

Journal of the Iowa Academy of Science: JIAS

This paper not available at time of printing.

The Future Of Lasers And Laser Applications, William C. Stwalley

Journal of the Iowa Academy of Science: JIAS

Lasers are increasingly used in· an astounding variety of scientific, engineering, medical and commercial applications. Here the prospective improvements in lasers will first be addressed, e.g., improvements in wavelength range, tunability, pulse duration, efficiency, cost, etc.

Laser applications will then be briefly surveyed, including selected topics involving basic research, materials processing, analytical and diagnostic applications, information transmission and storage, measurement and alignment and photochemical and biomedical application.

Results Of The August Roadside Survey For Upland Wildlife In Iowa: 1963-1988, Willie J. Suchy, Ronald J. Munkel, James M. Kienzler

Journal of the Iowa Academy of Science: JIAS

Results of the August roadside survey collected from 1963 through 1988 were examined to determine if trends could be detected in the counts of ring-necked pheasants (Phasianus colchicus), northern bobwhite (Colinus virginianus), gray partridge (Perdix perdix), cottontail rabbits (Sylvilagus floridanus), and white-tailed jackrabbits (Lepus townsendii). The counts also were compared to harvest estimates co determine if correlations exist. Statistically significant linear trends were detected statewide for pheasants, gray partridge and jackrabbits during the 1963 co 1988 period. Trends were downward for all species except gray partridge. During the late 12 years (1977 through 1988), the only significant trend detected was …

The Role Of Mechanical Injury In An Experimental Transmission Of Flexibacter Columnaris To Fingerling Walleye, Manzoor Hussain, Robert C. Summerfelt

Journal of the Iowa Academy of Science: JIAS

The role of mechanical injury in transmission of Flexibacter columnaris to walleye fingerlings (Stizostedion vitreum vitreum) was investigated. Two groups (1 and 2) of 10 fish each, 7 to 9 cm total length, were exposed to a suspension of F lexibacter columnaris containing 3 X 105 cfu/ mL; fish in group 1 were injured with a scratch along their flank; fish in group 2 were not injured. Two control groups (3 and 4) of 5 fish each were exposed to a sterile broth; group 3 was injured with a scratch and group 4 was not. In 72 h, morbidity was …

Lxodes Dammini (Acari, Ixodidae) And Borrelia Burgdorferi In Iowa, Mark G. Novak, Wayne A. Rowley, Kenneth B. Platt, David M. Bartholomew, Michelle D. Senne

Journal of the Iowa Academy of Science: JIAS

A statewide study to evaluate the presence, distribution and abundance of the deer tick, Ixodes dammini, and the spirochete, Borrelia burgdorfen, in Iowa was initiated in 1989. Six hundred and seventy-one tick collections were received from health professionals, conservation employees and concerned citizens. Additional ticks were obtained by flagging, small mammal trapping and deer checks in selected areas of Iowa. Nine I. dammini were collected in 1989 from seven counties in the eastern half of the state. Six of these were tested for B. burgdorferi and all were negative. Flagging, small mammal trapping and deer checks in eastern Iowa failed …

Vascular Flora Of Arend's Kettle, Freda Haffner Kettlehole State Preserve, Dickinson County, Iowa, Edwin L. Freese, William J. Platt

Journal of the Iowa Academy of Science: JIAS

Arend's Kettle is a 5 ha glacial landform in Dickinson County, Iowa. The flora of this kettle was studied over two years prior to acquisition by the Nature Conservancy in 1973. The known vascular flora of Arend's Kettle as of 1973 consisted of 299 species, representing 177 genera and 59 families. The vegetation ranged from xeric short grass prairie along the rims of the kettle to mesic prairie along the middle and lower slopes. In the bottom of the kettle, there was a marsh/seasonal pond community that varied greatly in the amount of water present, depending on rainfall within the …

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Journal of the Iowa Academy of Science: JIAS

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