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Full-Text Articles in Science and Mathematics Education

An Industry Perspective On The Benefits Of And Regulation Of Genetically Engineered Plants, Nicholas M. Frey Jan 1988

An Industry Perspective On The Benefits Of And Regulation Of Genetically Engineered Plants, Nicholas M. Frey

Journal of the Iowa Academy of Science: JIAS

The seed industry has routinely incorporated new technology into its research and development programs. Plant generic engineering is the most recent technology to be utilized for seed product development efforts. New sources of herbicide, insect, and disease resistance are being incorporated into crop plants using cellular and molecular biology techniques.

New regulatory guidelines have been developed which require regulatory approval before genetically engineered plants can be reseed in the field and ultimately marketed. The impact of these regulations on product development is unclear. Hopefully a dialogue will develop among industry, government agencies, and the public such that reasonable and appropriate …


Economic Changes From The Use Of Biotechnology In Production Agriculture, Loren W. Tauer Jan 1988

Economic Changes From The Use Of Biotechnology In Production Agriculture, Loren W. Tauer

Journal of the Iowa Academy of Science: JIAS

The potential economic impact of biotechnology in production agriculture is discussed. There are challenges and difficulties in completing economic research when little production information is available on biotechnologies. I argue that little impact differences exist between cost-reducing versus output-increasing technological change. Rapid technological change results in low average returns in agriculture but continuous early innovators earn higher returns. Various plant and animal technologies are presented and discussed.


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1988

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Agronomic Performance Of Sorghum Hybrids Produced By Using Different Male-Sterility-Inducing Cytoplasms, A. J. Maves, R. E. Atkins Jan 1988

Agronomic Performance Of Sorghum Hybrids Produced By Using Different Male-Sterility-Inducing Cytoplasms, A. J. Maves, R. E. Atkins

Journal of the Iowa Academy of Science: JIAS

Experiments were conducted in three environments in Iowa to obtain information on the effects of different cytoplasms on agronomic characters in grain sorghum (Sorghum bicolor L. Moench) hybrids. Compared with A1 cytoplasm, A2 and A3 cytoplasms delayed flowering; reduced the percentage of fertile pollen, the number of seeds per panicle, and grain yield; and increased 100-seed weight of the hybrids. Hybrids with A2 or A3 cytoplasm did not differ (p ≥0.05) from those in the A1 cytoplasm for plant height, panicles per plant, or for length, width, and area of the third and fourth leaves from the top of …


Evaluation Of Fish Eradication And Game-Fish Restocking In A Central Iowa Pond, Dennis L. Scarnecchia Jan 1988

Evaluation Of Fish Eradication And Game-Fish Restocking In A Central Iowa Pond, Dennis L. Scarnecchia

Journal of the Iowa Academy of Science: JIAS

Changes in fish community and population structure associated with fish eradication and subsequent restocking were investigated in a small (0. 25 ha) impoundment in Boone County, Iowa. In September 1985, when fish were eradicated with rotenone, the fish community consisted of eight species. Large numbers of small bluegills (Lepomis macrochirus), green sunfish (Lepomis ryanellus), and stunted crappies (Pomoxis spp.) dominated the pond numerically, but seven large carp (Cyprinus carpio) and 18 large bigmouth buffalo (lctiobus ryprinellus) constituted 80% of the total biomass. The only quality angling (popular species of desirable size) was for a few largemouth bass (Micropterus salmoides) and …


Front Matter Jan 1988

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Soil N Availability And Nitrogen Harvest Index Of Oats, N. Md. Kairudin, K. J. Frey Jan 1988

Soil N Availability And Nitrogen Harvest Index Of Oats, N. Md. Kairudin, K. J. Frey

Journal of the Iowa Academy of Science: JIAS

A population of 480 random lines of oats (Avena sativa L.) was grown on soil that received no application of nitrogen (N) or 112 kg of N ha-1 (defined as low- and high-N environments, respectively) to evaluate the effect of N availability in the soil on the plant's ability to partition N between vegetative tissue and the grain, a ratio defined as nitrogen harvest index. Also, comparisons were made between low and high-N environments for grain yield, straw yield, biological yield, groat protein yield, groat protein percentage, vegetative protein yield, straw protein percentage, total plant protein yield, and harvest …


Anthracnose Kernel Rot Of Maize Caused By Colletotrichum Graminicola (Ces.) Wils.: Mode Of Entrance Into And Disease Progression In Ears, Claude Nankam, D. C. Foley Jan 1988

Anthracnose Kernel Rot Of Maize Caused By Colletotrichum Graminicola (Ces.) Wils.: Mode Of Entrance Into And Disease Progression In Ears, Claude Nankam, D. C. Foley

Journal of the Iowa Academy of Science: JIAS

The mode of establishment of Colletotrichum graminicola in maize ears to cause kernel infection was studied for two types of infective propagules and three sites of penetration. Shank inoculations with either oat-grain inoculum or spores induced a greater percentage of infected kernels than inoculations of the husk or kernel area with an infected oat grain or inoculations of the silks with an oat grain or a spore suspension in 1985. But in 1986, a spore suspension in the kernels ranked first among all the treatments based on the basis of disease severity on the kernels. However, a large percentage of …


Some Genetic Characteristics Of Three Walleye Stocks In Iowa And The Impact Of Fry Stockings In The Cedar River, Vaughn L. Paragamian Jan 1988

Some Genetic Characteristics Of Three Walleye Stocks In Iowa And The Impact Of Fry Stockings In The Cedar River, Vaughn L. Paragamian

Journal of the Iowa Academy of Science: JIAS

Fry stockings of walleye Stizostedion v. vitreum into the Cedar River, Iowa began in the early 1950's, and two studies of the success of these plants gave conflicting results. The objectives of my study were to identify some genetic characteristics in three stocks of walleye and to utilize these characteristics to assess the genetic impact of fry stockings in the Cedar River. Electrophoretic analysis of malate dehydrogenase (MDH) and isocitrate dehydrogenase (IDH) was completed for walleye stocks from the Mississippi and Cedar Rivers, and Big Spirit Lake, Iowa. Phenotypic frequencies of Mdh - B2 and Mdh - B3 …


Reevaluating Evidence For The Pre-Lllinoian Entrenchment Of Northeastern Iowa River Valleys, Curtis M. Hudak Jan 1988

Reevaluating Evidence For The Pre-Lllinoian Entrenchment Of Northeastern Iowa River Valleys, Curtis M. Hudak

Journal of the Iowa Academy of Science: JIAS

Previous workers have proposed a pre-Illinoian age for the deepest bedrock entrenchment of northeastern Iowa valleys. Lines of evidence used to support a pre-Illinoian age of entrenchment are: (1) deep bedrock-entrenchment interpreted to take "long" periods of time, (2) "valleys" filled with "red-weathered drift", which was interpreted as "old", (3) differences in cross-valley profiles supposedly related to glacial advances, (4) thick beds of gravel could only be deposited by outwash streams, and (5) glacially buried (drift-filled) bedrock valleys exist outside of the Paleozoic Plateau to the west and south. These inferences are questionable because: ( 1) erosion (entrenchment) rates are …


Recompact Iowa Soil Materials Before Using As Liners For Waste Containment, G. J. Kluitenberg, R. Horton, M. L. Thompson, J. F. Mcbride Jan 1988

Recompact Iowa Soil Materials Before Using As Liners For Waste Containment, G. J. Kluitenberg, R. Horton, M. L. Thompson, J. F. Mcbride

Journal of the Iowa Academy of Science: JIAS

Soil materials are often used in hazardous-waste disposal facilities to provide a physical barrier to leachate movement. Both existing soils and recompacted soil materials have been used in barrier construction. Solute transport experiments and measurements of saturated hydraulic conductivity were used to characterize the solute transport properties of three Iowa soil materials. Experiments were carried out by using undisturbed soil samples as well as recompacted samples. The experimental results show that recompaction greatly altered the solute transport properties of the three soil materials. It is concluded that recompaction is necessary for any of these materials to satisfy Environmental Protection Agency …