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Full-Text Articles in Education

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 …


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 …