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Neonicotinoid Insecticide Removal By Prairie Strips In Row-Cropped Watersheds With Historical Seed Coating Use, Michelle L. Hladik, Steven P. Bradbury, Lisa A. Schulte, Matthew Helmers, Christopher Witte, Dana W. Kolpin, Jessica D. Garrett, Mary Harris 2017 United States Geological Survey

Neonicotinoid Insecticide Removal By Prairie Strips In Row-Cropped Watersheds With Historical Seed Coating Use, Michelle L. Hladik, Steven P. Bradbury, Lisa A. Schulte, Matthew Helmers, Christopher Witte, Dana W. Kolpin, Jessica D. Garrett, Mary Harris

Lisa A. Schulte Moore

Neonicotinoids are a widely used class of insecticides that are commonly applied as seed coatings for agricultural crops. Such neonicotinoid use may pose a risk to non-target insects, including pollinators and natural enemies of crop pests, and ecosystems. This study assessed neonicotinoid residues in groundwater, surface runoff water, soil, and native plants adjacent to corn and soybean crop fields with a history of being planted with neonicotinoid-treated seeds from 2008 to 2013. Data from six sites with the same crop management history, three with and three without in-field prairie strips, were collected in 2015–2016, 2–3 years after neonicotinoid ...


Predicted Gains From Recurrent Selection In The Bs11 Maize Population, P. S. Guzman, K. R. Lamkey 2017 Iowa State University

Predicted Gains From Recurrent Selection In The Bs11 Maize Population, P. S. Guzman, K. R. Lamkey

Kendall R Lamkey

Random genetic drift and inbreeding depression resulting from the use of small effective population size limit the gain of recurrent selection programs. The objectives of our study were to predict the gains of S2, S1, full-sib, and modified-ear-to-row recurrent selection methods in maize (Zea mays L.) with varying effective population sizes of 5, 10, 20, and 30 and to compare these predicted gains with the realized gains obtained in a related study. Using the variance estimates of the BS11C0 population, predicted gain cycle-1 was computed based on single trait selection and index selection. Predicted gain cycle-1 for S1-progeny selection method ...


Hardy-Weinberg And Linkage Equilibrium Estimates In The Bsss And Bscb1 Random Mated Populations, J. A. Labate, K. R. Lamkey, M. Lee, W. Woodman 2017 Cornell University

Hardy-Weinberg And Linkage Equilibrium Estimates In The Bsss And Bscb1 Random Mated Populations, J. A. Labate, K. R. Lamkey, M. Lee, W. Woodman

Kendall R Lamkey

Because maize (Zea mays) is an annual species those working with it must frequently make crosses to preserve and periodically maintain populations. Random mating is performed either using hand-pollination techniques or in wind-pollinated isolated blocks. Eighty-two restriction fragment length polymorphism (RFLP) markers were used to examine samples of random mated, hand-pollinated BSSS(R) and BSCB1(R) maize populations to find out whether their genotypic proportions conformed to predicted outcomes of random mating. The majority of loci conformed to expectations for Hardy-Weinberg equilibrium (HWE). Excess homozygosity was observed at 87% of the loci where the null hypothesis of HWE was rejected ...


Response To Selection And Changes In Genetic Parameters For 13 Plant And Ear Traits In Two Maize Recurrent Selection Programs, J. F. Holthaus, K. R. Lamkey 2017 Holden's Foundation Seeds, Inc.

Response To Selection And Changes In Genetic Parameters For 13 Plant And Ear Traits In Two Maize Recurrent Selection Programs, J. F. Holthaus, K. R. Lamkey

Kendall R Lamkey

Recurrent selection is a cyclical breeding procedure that focuses on improving the mean performance of a population by increasing the frequency of favorable alleles and maintaining adequate genetic variability for continued selection response. The Iowa Stiff Stalk Synthetic (BSSS) maize (Zea mavs L.) population has undergone continuous recurrent selection for more than 50 years as the base population for two independent selection programs. This study was designed to estimate the mean performance and important genetic parameters in BSSS before and after seven cycles of half- sib (I IS) progeny selection, six cycles of Srprogeny selection, and 11 cycles of reciprocal ...


Fifty Years Of Recurrent Selection In The Iowa Stiff Stalk Synthetic Maize Population, K. R. Lamkey 2017 U.S. Department of Agriculture

Fifty Years Of Recurrent Selection In The Iowa Stiff Stalk Synthetic Maize Population, K. R. Lamkey

Kendall R Lamkey

Recurrent selection is a breeding procedure designed to increase the frequency of favorable alleles in a population. Increasing the frequency of favorable alleles will increase the probability of obtaining surerior inbred line.s for use in hybrids. The Iowa Stiff Stalk Synthetic (BSSS) maize (£ea mays I..) population has been involved in continuous recurrent selection since 1939. Thirteen cycles of selection have been completed . The first seven cycles were half-sib selection using the double-cross lowa 13 as a tester. After completion of seven cycles of half-sih selection, the population was renamed BSU and six cycles of S2-progeny selection were completed ...


Evaluation Of A Modified Reciprocal Recurrent Selection Procedure For Maize Improvement, W. A. Russell, D. J. Blackburn, Kendall R. Lamkey 2017 Iowa State University

Evaluation Of A Modified Reciprocal Recurrent Selection Procedure For Maize Improvement, W. A. Russell, D. J. Blackburn, Kendall R. Lamkey

Kendall R Lamkey

Reciprocal recurrent selection in maize (:Zea mays L.) has been ve1y successful in improving yields of crosses of two populations wherein each population has been used as a tester for the other. A modification of the procedure was suggested that uses two inbred lines as testers instead of the populations. The purpose of our research was to compare the two procedures for progress achieved after three cycles of recurrent selection. The populations were BS21 and BS22 Synthetics used in a reciprocal recurrent selection program (BS21R x BS22R). For the modified procedure, inbred A632 was the tester for BS21, [BS21(A632Hl ...


Population Genetics Of Increased Hybrid Performance Between Two Maize Populations Under Reciprocal Recurrent Selection, J. A. Labate, K. R. Lamkey, M. Lee, W. L. Woodman 2017 Iowa State University

Population Genetics Of Increased Hybrid Performance Between Two Maize Populations Under Reciprocal Recurrent Selection, J. A. Labate, K. R. Lamkey, M. Lee, W. L. Woodman

Kendall R Lamkey

Heterosis, the superiority in one or more characteristics of crossbred organisms relative to their inbred parents, is the basis of the modern cultivars utilized in maize (Zed mays L.). Heterosis is of interest in nondomesticated species due to its relevance to the question "how much polymorphism is maintained in natural populations due to selection?" (Berger, 1976). For maize and certain other domesticated species that employ inbred lines to produce commercial hybrids, knowledge of the mechanisms of gene action producing heterosis could contribute to advances in breeding techniques.


Potential For Sorghum Genotypes In A Double-Cropping System, Ben Michael Goff, Kenneth J. Moore, Steven L. Fales, Emily A. Heaton 2017 Iowa State University

Potential For Sorghum Genotypes In A Double-Cropping System, Ben Michael Goff, Kenneth J. Moore, Steven L. Fales, Emily A. Heaton

Emily Heaton

The majority of the ethanol currently produced in the United States is derived from the hydrolysis and fermentation of starch provided from corn (Zea mays) grain. Although this is a suitable temporary solution, there are some long-term issues associated with continued use of corn grain as an ethanol feedstock. It has been estimated that if the entire U.S. corn crop was used for ethanol production, it would only meet approximately 15 to 25% of the U.S. transportation fuel need. Thus ethanol produced from biomass is expected to help meet the energy needs that grain ethanol may not provide.


New Isu Research May Help Farmers Make More Informed Decisions About Land Use, Elke Brandes, Emily A. Heaton, Lisa A. Schulte-Moore, Fred Love 2017 Iowa State University

New Isu Research May Help Farmers Make More Informed Decisions About Land Use, Elke Brandes, Emily A. Heaton, Lisa A. Schulte-Moore, Fred Love

Emily Heaton

A new study from a multidisciplinary team led by Iowa State University agronomists shows that significant portions of Iowa farmland consistently lose money and could influence many farmers to change how they use some of the acres they devote to corn and soybeans.


Miscanthus Establishment And Survival, Nicholas N. Boersma, Emily A. Heaton 2017 Iowa State University

Miscanthus Establishment And Survival, Nicholas N. Boersma, Emily A. Heaton

Emily Heaton

Rising costs of petroleum fuels and increased awareness of the adverse effects of greenhouse gases have spurred interest in renewable fuels and other ‘green’ products. Recent legislation has set goals of approximately 20 billion gallons of renewable fuel produced from non-corn starch sources by the year 2022. These driving forces have increased interest in dedicated bioenergy crops. Among perennial grasses, which have received an exceptional amount of attention as dedicated energy crops, one stands out: Miscanthus (Miscanthus × giganteus).


Miscanthus Establishment And Survival, Nicholas N. Boersma, Emily A. Heaton 2017 Iowa State University

Miscanthus Establishment And Survival, Nicholas N. Boersma, Emily A. Heaton

Emily Heaton

Rising costs of petroleum fuels and increased awareness of the adverse effects of greenhouse gases have spurred interest in renewable fuels and other ‘green’ products. Recent legislation has set goals of approximately 20 billion gallons of renewable fuel produced from non-corn starch sources by the year 2022. These driving forces have increased interest in dedicated bioenergy crops. Among perennial grasses, which have received an exceptional amount of attention as dedicated energy crops, one stands out: Miscanthus (Miscanthus x giganteus).


Is It Too Late To Dig Miscanthus For Spring Planting?, Emily A. Heaton, Nicholas N. Boersma 2017 Iowa State University

Is It Too Late To Dig Miscanthus For Spring Planting?, Emily A. Heaton, Nicholas N. Boersma

Emily Heaton

Giant Miscanthus (Miscanthus × giganteus) is a perennial warm-season grass used for bioenergy, and is being planted on thousands of acres in Missouri and Arkansas this spring. Given the warm spring, and the high level of interest in Miscanthus this year, we have been getting lots of questions around propagation and planting.


Farm-Scale Costs And Returns For Second Generation Bioenergy Cropping Systems In The Us Corn Belt, Robert K. Manatt, Arne Hallam, Lisa A. Schulte, Emily A. Heaton, Theodore P. Gunther, Richard B. Hall, Kenneth J. Moore 2017 Iowa State University

Farm-Scale Costs And Returns For Second Generation Bioenergy Cropping Systems In The Us Corn Belt, Robert K. Manatt, Arne Hallam, Lisa A. Schulte, Emily A. Heaton, Theodore P. Gunther, Richard B. Hall, Kenneth J. Moore

Emily Heaton

While grain crops are meeting much of the initial need for biofuels in the US, cellulosic or second generation (2G) materials are mandated to provide a growing portion of biofuel feedstocks. We sought to inform development of a 2G crop portfolio by assessing the profitability of novel cropping systems that potentially mitigate the negative effects of grain-based biofuel crops on food supply and environmental quality. We analyzed farm-gate costs and returns of five systems from an ongoing experiment in central Iowa, USA. The continuous corn cropping system was most profitable under current market conditions, followed by a corn–soybean rotation ...


Economies Of Scale In Integrated Pest Management In Vegetable And Fruit Production, Franklin Quarcoo, Conrad Bonsi, David Nii O. Tackie, Walter A. Hill, Gertrude Wall, George Hunter 2017 Tuskegee University

Economies Of Scale In Integrated Pest Management In Vegetable And Fruit Production, Franklin Quarcoo, Conrad Bonsi, David Nii O. Tackie, Walter A. Hill, Gertrude Wall, George Hunter

Professional Agricultural Workers Journal

Abstract

Pest management is achieved directly using a variety of tools, including pesticides, and indirectly through a number of agronomic/cultural practices such as irrigation and fertilizer application; collectively these practices function to positively effect general plant health. Healthier plants are more resistant to or tolerant of pests. This study explores the scale differences that impact the pest management significance and suitability of certain agronomic practices. Scale differences were discussed using literature-based information, direct field observations, and anecdotal information on the relative advantages of drip and sprinkler irrigation systems; organic and conventional cultivation of crops; crop rotation versus mono-cropping systems ...


1938 Iowa Corn Yield Test, Marcus S. Zuber, Joe L. Robinson 2017 U.S.D.A.

1938 Iowa Corn Yield Test, Marcus S. Zuber, Joe L. Robinson

Bulletin

A total of 1,110 district entries was made in the 12 fields of the 1938 Iowa Corn Yield Test. These were divided into three groups on the basis of the indicated seed grown by the entrant in 1937; Regular Open-Pollinated, Regular Hybrids, and Experimental Hybrids.


Marketing Iowa Cantaloupes, A. T. Erwin, Geoffrey Shepherd, N. D. Morgan 2017 Iowa State College

Marketing Iowa Cantaloupes, A. T. Erwin, Geoffrey Shepherd, N. D. Morgan

Bulletin

Cantaloupe production is well adapted to the sand land areas. This type of soil, though not well adapted to corn and general farm crops, may be advantageously devoted to cantaloupe growing.

Cantaloupe marketing in Iowa presents a number of interesting and complex problems. These include consideration of varietal adaptation, the temperature factor, changes in transporting and selling agencies and competing areas of production. The objective of this bulletin is to show clearly what these problems are and to suggest possible methods of meeting them.


The 1937 Iowa Corn Yield Test, Joe L. Robinson, R. C. Eckhardt, M. M. Rhoades, M. S. Zuber 2017 Iowa State College

The 1937 Iowa Corn Yield Test, Joe L. Robinson, R. C. Eckhardt, M. M. Rhoades, M. S. Zuber

Bulletin

The purpose of the Iowa Corn Yield Test is to find for each district and section of the state those strains of open-pollinated corn and hybrid combinations which produce the greatest yield, mature properly, possess resistance to lodging and have good quality or possess other characteristics which might make them desirable. Significant differences in these characteristics between different kinds of corn grown in adequately replicated tests may be attributed to differences inherent in the strains.


Barley In Iowa, L. C. Burnett, Chas. S. Reddy 2017 Iowa State College

Barley In Iowa, L. C. Burnett, Chas. S. Reddy

Bulletin

Barley yields in Iowa are higher than those for oats, but in spite of this 15 times more acres are sown to oats than to barley. During the 10 year period, 1925-34, the farms of Iowa produced average acre yields of 1,007 pounds of oats on 6,000,000 acres and 1,238 pounds of barley on 460,000 acres. Figure 1, presenting data from the Iowa Year Book of Agriculture, shows the relative acreage and acre yields of the two crops from 1900 to 1934. In order that a direct comparison may readily be made, the yields of ...


Hybrid Corn In Iowa, A. A. Bryan, R. W. Jugenheimer 2017 Iowa State College

Hybrid Corn In Iowa, A. A. Bryan, R. W. Jugenheimer

Bulletin

Hybrid corn is a comparatively recent development. Extensive breeding programs for the development of corn hybrids date from only about 1920—the Iowa program was begun in 1922. Despite the newness of hybrid corn, yield comparisons in the Iowa Corn Yield Test during the past 10 years have adequately demonstrated the superiority of certain hybrids over the best open-pollinated varieties. Results of these and other comparisons have awakened among growers a keen interest in the possibilities of hybrid corn.

Every grower is interested in obtaining large acre yields. The net profit from growing a bushel of corn is the difference ...


The 1936 Iowa Corn Yield Test, M. M. Rhoades, Joe L. Robinson 2017 Iowa State College

The 1936 Iowa Corn Yield Test, M. M. Rhoades, Joe L. Robinson

Bulletin

1. Eight hundred seventy-nine entries were made in the 10 harvested districts of the 1936 Iowa Corn Yield Test. The yield test fields in districts 4 and 7 were abandoned because of crop failure. The entries were divided into four groups; regular open-pollinated, experimental open-pollinated, regular hybrids and experimental hybrids.

2. Data were obtained for each entry on acre yield, percentage stand, moisture content at time of harvest, lodging resistance, ear height, percentage of dropped ears and percentage of damaged kernels.

3. The outstanding feature of the 1936 Iowa Corn Yield Test was the superior performance of the hybrid combinations ...


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