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Cover - Table Of Contents Jan 1991

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Back Cover Jan 1991

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Part I - Papers Presented At The 1989 Plant Science Lecture Series Jan 1991

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.


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1991

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1991

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Cover - Table Of Contents Jan 1991

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Comparison Of Mass Selection And S1 Testing Recurrent-Selection Methods In Sorghum, R. E. Secrist, R. E. Atkins Jan 1991

Comparison Of Mass Selection And S1 Testing Recurrent-Selection Methods In Sorghum, R. E. Secrist, R. E. Atkins

Journal of the Iowa Academy of Science: JIAS

Mass selection and S1 testing are often used for the improvement of sorghum [Sorghum bicolor (L.) Moench] populations. Both recurrent selection methods have a place in applied breeding programs and should be used where they are likely to be most advantageous. S1 families of a random-mating sorghum population mass selected three cycles (C3) for individual-panicle weight [IAP1R(M)C3] were compared with S1 families from a population (C3) advanced from the same base (CO) population by using replicated yield tests in each cycle [ IAP4R(S1)C3]. Our objectives were to compare the performance in C3 of ...


Studies Of The Precambrian Geology Of Iowa: Part 1. The Otter Creek Layered Igneous Complex, Kenneth E. Windom, Karl E. Seifert, Raymond R. Anderson Jan 1991

Studies Of The Precambrian Geology Of Iowa: Part 1. The Otter Creek Layered Igneous Complex, Kenneth E. Windom, Karl E. Seifert, Raymond R. Anderson

Journal of the Iowa Academy of Science: JIAS

Rocks from a buried igneous body, herein called the Otter Creek layered igneous complex, were recovered by drilling in Archean rocks in northwestern Iowa. This complex consists of layers of ultramafic and mafic cumulate rocks, including bronzitite, harzburgite, dunite, gabbro, and anorthosite. These rocks have been subjected to low-grade metamorphism with a patagenesis including serpentine, chlorite, talc, uralitic amphiboles, magnetite, albite, epidote, sericite, and minor quartz and calcite. During its intrusion, the magma which gave rise to the layered body engulfed a large block of rock consisting of banded iron formation and thin lamprophyre dikes. Both the iron formation and ...


Solid Substrate Room-Temperature Phosphorescence Of Phenothiazine And Related Compounds, William D. Savage, Ronald T. Pflaum, Catherine Hinga Haustein Jan 1991

Solid Substrate Room-Temperature Phosphorescence Of Phenothiazine And Related Compounds, William D. Savage, Ronald T. Pflaum, Catherine Hinga Haustein

Journal of the Iowa Academy of Science: JIAS

The room-temperature phosphorescence characteristics of phenothiazine, phenothiazine-based pharmaceuticals, and related compounds are presented. It was found that substitution onto the parent ring produces little variation in RTP excitation and emission wavelengths, but electron withdrawing substituents reduce RTP intensity. Procedures for the determination of procaine and promethazine in urine and clorpromazine in whole blood are presented.


Estimates Of Quantitative Genetic Parameters M Iap2b(M) Random-Mating Sorghum Population, A. J. Maves, R. E. Atkins Jan 1991

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 ...


Journal Of The Iowa Academy Of Science Submission Form And Instruction Sheet Jan 1991

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

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 Jan 1991

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 ...


Food Habits Of The Northern Saw-Whet Owl In Central Iowa: Effects Of Roost Location, Stephen J. Dinsmore, William R. Clark Jan 1991

Food Habits Of The Northern Saw-Whet Owl In Central Iowa: Effects Of Roost Location, Stephen J. Dinsmore, William R. Clark

Journal of the Iowa Academy of Science: JIAS

During the period 1979-89, 900 northern saw-whet owl (Aegolius acadicus) pellets with identifable remains of prey were collected at 18 central Iowa locations. Peromyscus were the most frequent prey consumed, comprising 81.2% of all prey items. Other prey species were voles (Microtus), western harvest mice (Reithrodontomys megalotis), shrews (Blarina brevicauda, Sorex cinereus, and Cryptotis parva), and a single unidentified bird. Peromyscus comprised the largest proportion of pellets from different successional stages. There were significant differences for four prey groups (Peromyscus, Microtus, Reithrodontomys, and shrews) among years. Peromyscus and R. megalotis showed significant differences among locations. Microtus and shrews were ...


Results Of The August Roadside Survey For Upland Wildlife In Iowa: 1963-1988, Willie J. Suchy, Ronald J. Munkel, James M. Kienzler Jan 1991

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 ...


Iowa's Climate As Projected By The Global Climate Model Of The Goddard Institute For Space Studies For A Doubling Of Atmospheric Carbon Dioxide, E. S. Takle, S. Zhong Jan 1991

Iowa's Climate As Projected By The Global Climate Model Of The Goddard Institute For Space Studies For A Doubling Of Atmospheric Carbon Dioxide, E. S. Takle, S. Zhong

Journal of the Iowa Academy of Science: JIAS

Results of a global climate model that simulates climate under a doubling of atmospheric carbon dioxide (estimated to occur by the latter half of the twenty first century) have been interpolated to Iowa. Summer temperatures under such a doubling are projected to rise by 4 to 7°F (2.2 to 3.9°C) and winter temperatures by 10 to 11° (5.6 to 6.1°C). Estimates of space heating and cooling demands from these data suggest a 30 to 35% decrease in space heat demand and a 200 to 300% increase in space cooling demand. Temperature variability is ...


The Axr1 Mutation Of Arabidopsis Is Expressed 10 Booth Roots And Shoots, Cythia Lincoln, Mark Estelle Jan 1991

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 ...


Comparison Of Dinitrogen Fixation And Nitrogen Transfer Potentials Of Four Red Clover Cultivars, D. E. Farnham, A. P. Mallarino, W. F. Wedin, I. T. Carlson Jan 1991

Comparison Of Dinitrogen Fixation And Nitrogen Transfer Potentials Of Four Red Clover Cultivars, D. E. Farnham, A. P. Mallarino, W. F. Wedin, I. T. Carlson

Journal of the Iowa Academy of Science: JIAS

The capacity to fix atmospheric N2 and thus reduce the use of N fertilizer is an important reason for including legumes in forage mixtures. Selection for more efficient N2 fixation could improve red clover (Trifolium prateme L.) (RC) production and its contribution to soil fertility. An isotope dilution study was conducted in two greenhouse experiments to compare the N2 fixation and N transfer potentials of three commercial and one experimental RC cultivars. The experimental cultivar APR-8701 was selected for traits related to increased N2 fixation (rate of acetylene reduction, root size and branch number, and nodule ...


Regulation Of Phytochrome Gene Expression, J. T. Colbert, S. A. Costigan, P. Avissar, Z. Zhao Jan 1991

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 ...


Annual Report Of The Iowa Academy Of Science, 1989-90, Paul E. Rider Jan 1991

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.


Vascular Flora Of Arend's Kettle, Freda Haffner Kettlehole State Preserve, Dickinson County, Iowa, Edwin L. Freese, William J. Platt Jan 1991

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 ...