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Iowa State University

Plant Sciences

2015

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Transcriptome Profiling Of Soybean (Glycine Max) Roots Challenged With Pathogenic And Non-Pathogenic Isolates Of Fusarium Oxysporum, Alessandra Lanubile, Usha K. Muppirala, Andrew J. Severin, Adriano Marocco, Gary P. Munkvold Dec 2015

Transcriptome Profiling Of Soybean (Glycine Max) Roots Challenged With Pathogenic And Non-Pathogenic Isolates Of Fusarium Oxysporum, Alessandra Lanubile, Usha K. Muppirala, Andrew J. Severin, Adriano Marocco, Gary P. Munkvold

Plant Pathology and Microbiology Publications

Background
Fusarium oxysporum is one of the most common fungal pathogens causing soybean root rot and seedling blight in U.S.A. In a recent study, significant variation in aggressiveness was observed among isolates of F. oxysporum collected from roots in Iowa, ranging from highly pathogenic to weakly or non-pathogenic isolates.

Results
We used RNA-seq analysis to investigate the molecular aspects of the interactions of a partially resistant soybean genotype with non-pathogenic/pathogenic isolates of F. oxysporum at 72 and 96 h post inoculation (hpi). Markedly different gene expression profiles were observed in response to the two isolates. A peak ...


Iowa State Research Farm Reports Available To Public, Mark S. Honeyman Dec 2015

Iowa State Research Farm Reports Available To Public, Mark S. Honeyman

Integrated Crop Management News

There are fourteen Iowa State University Research and Demonstration Farms in Iowa; nine owned by associations (local farmers) and five owned by the university. One responsibility of Iowa State to the associations is to provide an annual farm progress report on the agricultural research and related scientific agriculture activities conducted at the farm as a year-end summary. Those reports, that were made available in the past to the members and others in print form, are now available online to the public athttp://fpr.extension.iastate.edu/ in a new format.


Nitrogen Loss?, John E. Sawyer Dec 2015

Nitrogen Loss?, John E. Sawyer

Integrated Crop Management News

Really, it just had to rain large amounts in December. Seems we can’t get any relief from worrying about excess rain and impacts on nitrogen (N). The questions have already begun – what about fall 2015 fertilizer and manure N applications? It is quite hard to make an estimate of losses for such an extreme event and time of the year. Following are factors to consider that will affect loss potential, including if N was applied and if so what fertilizer product or manure source.


Hindsight Is 20/20: What Can Be Learned From 2015, Mark Licht, Sotirios Archontoulis Dec 2015

Hindsight Is 20/20: What Can Be Learned From 2015, Mark Licht, Sotirios Archontoulis

Integrated Crop Management News

As the saying goes, hindsight is 20/20; perfect vision. We often say “if we knew the weather, then we can provide the best recommendations”. Usually, we do not know the weather or we do not have the appropriate tools in place, so the questions remain unanswered. Now that we know the weather, the next important question is to determine what could have been done differently in 2015. This is an important part of understanding and evaluating production and environmental performance of our crop management decisions. In this article, we leverage our knowledge of the 2015 weather and use the ...


Yield Gap Analysis: What Limited Iowa Corn And Soybean Yields In 2015, Sotirios Archontoulis, Mark Licht Dec 2015

Yield Gap Analysis: What Limited Iowa Corn And Soybean Yields In 2015, Sotirios Archontoulis, Mark Licht

Integrated Crop Management News

To evaluate how good corn and soybean yields were in 2015, farmers and agronomists compare their yields to those obtained in previous years. To answer why yields were higher or lower than past years, they develop hypotheses to explain factors that limited yields based on their own experiences, anecdotal evidence from neighbors, knowledge of crop growth and development, and weather patterns. As a next step to the in-season Yield Forecast Project, we can provide an alternative analysis and a yield gap analysis of the 2015 growing season by using the explanatory power that a cropping systems model offers. Our analysis ...


Impact Of Energy Crops On Soil And Water Management, Michael G. Berntson, Samuel J. Groenenboom, Aaron K. Broennimann, Luke D. Muegge Dec 2015

Impact Of Energy Crops On Soil And Water Management, Michael G. Berntson, Samuel J. Groenenboom, Aaron K. Broennimann, Luke D. Muegge

TSM 325 Biorenewable Systems Posters

Soil erosion is a major issue on many farms. With current corn and soybean practices there is a great deal of soil erosion during the standard growing season due to rain. As the soil is carried away by the rain fertilizer goes with it causing fertilizer infiltration and removing the fertilizer from the farm.


Certified Crop Adviser Exam Review Course Offered By Isu Extension, Brent A. Pringnitz Dec 2015

Certified Crop Adviser Exam Review Course Offered By Isu Extension, Brent A. Pringnitz

Integrated Crop Management News

Individuals planning to become a Certified Crop Adviser (CCA) can attend a two-day ISU Extension course to assist with exam preparation. ISU extension specialists will cover the performance objectives for the exam and provide additional assistance on topic areas of most concern to students. Students will take interactive quizzes during the course and finish with a practice examination.


Confinement Site Manure Applicator Workshops Scheduled For 2011, Angela M. Rieck-Hinz Dec 2015

Confinement Site Manure Applicator Workshops Scheduled For 2011, Angela M. Rieck-Hinz

Integrated Crop Management News

Confinement site manure applicators and anyone interested in learning about manure issues should plan to attend a two-hour workshop offered by Iowa State University (ISU) Extension in January or February 2011. These workshops are offered in cooperation with the Iowa Department of Natural Resources (DNR). There is no fee to attend the workshops, but applicators will need to pay certification fees to complete certification requirements.


Commercial Manure Applicator Training Scheduled For Jan. 6, 2011, Angela M. Rieck-Hinz Dec 2015

Commercial Manure Applicator Training Scheduled For Jan. 6, 2011, Angela M. Rieck-Hinz

Integrated Crop Management News

Commercial manure applicators can attend three hours of training on Thursday, Jan. 6, 2011, to meet annual commercial manure applicator certification requirements. Iowa State University (ISU) Extension and the Iowa Department of Natural Resources (DNR) will conduct Commercial Manure Applicator training from 9 a.m. to noon at 75 locations in Iowa, and four locations in surrounding states. Registration begins at 8:30 a.m. There is no fee for the workshop but applicators must register by Dec. 30 with the ISU Extension county office where they plan to attend. A complete list of county extension offices offering this workshop ...


Wrap Up And Validation Of The Yield Forecast Project For 2015, Sotirios Archontoulis, Mark Licht, Ranae N. Dietzel Dec 2015

Wrap Up And Validation Of The Yield Forecast Project For 2015, Sotirios Archontoulis, Mark Licht, Ranae N. Dietzel

Integrated Crop Management News

During the 2015 growing season, a group of scientists from the Department of Agronomy ran a pilot project with the objective of forecasting end-of-season yields and in-season water and nitrogen dynamics (crop demand and soil supply). In-season updates were put in past ICM News articles (June 17th, July 31st, and August 14th). Briefly, this project combined the use of a cropping systems model (APSIM), a climate model (WRF), and high-resolution, in-season measurements to create the forecasts. The project focused on eight cropping systems in 2015: two sites (Ames and Sutherland), two crops (corn and soybean), and two ...


Protect Your Investment By Eliminating Tillage And Keeping Residue, Mahdi M. Al-Kaisi Dec 2015

Protect Your Investment By Eliminating Tillage And Keeping Residue, Mahdi M. Al-Kaisi

Integrated Crop Management News

This fall, field observations with significant amounts of intensive tillage and residue removal provide an opportunity to rethink such practices by considering research proven practices such as no-tillage (NT) and strip-tillage (ST), which have demonstrated their effectiveness in many parts of the state and across the Midwest. Many studies from the Midwest and elsewhere have documented the economic benefits of NT and ST for both corn and soybean, where the conventional tillage input cost was greater than that of NT and ST by $15-25/acre in a study covering 14 years of tillage and crop rotations in Iowa.


Assessment Of Certified Crop Adviser Experience With And Knowledge Of Early And Mid-Season Soybean Diseases Caused By Oomycetes: 2015, J. Gordon Arbuckle Jr., Nick Kalaitzandonakes, James Kaufman, Alison Robertson Dec 2015

Assessment Of Certified Crop Adviser Experience With And Knowledge Of Early And Mid-Season Soybean Diseases Caused By Oomycetes: 2015, J. Gordon Arbuckle Jr., Nick Kalaitzandonakes, James Kaufman, Alison Robertson

Sociology Technical Reports

This report presents the results of a web-based survey of certified crop advisers (CCAs) conducted as part of the Integrated Management of Oomycete Diseases of Soybean and other Crop Plants Project funded by USDA-NIFA. The survey is part of a project-long effort to engage members of the Certified Crop Adviser program of the American Society of Agronomy and other crop advisers in educational and extension activities to improve their ability to accurately diagnose and manage soybean seedling and root diseases, particularly those caused by oomycetes. The report consists of three sections. This first section describes the survey’s objectives and ...


The Effectiveness Of A Single Regional Model In Predicting Non-Native Woody Plant Naturalization In Five Areas Within The Upper Midwest (United States), Philip M. Dixon, Janette R. Thompson, Mark P. Widrlechner, Emily J. Kapler Dec 2015

The Effectiveness Of A Single Regional Model In Predicting Non-Native Woody Plant Naturalization In Five Areas Within The Upper Midwest (United States), Philip M. Dixon, Janette R. Thompson, Mark P. Widrlechner, Emily J. Kapler

Horticulture Publications

Numerous predictive models have been developed to determine the likelihood that non-native plants will escape from cultivation and potentially become invasive. Given the substantial biological and economic costs that can result from the introduction of a new invasive plant and the unending pressures of world trade and transport, the creation and implementation of effective predictive models are becoming increasingly important. One key question in the development of such models focuses on the geographic scope at which models can best be developed and applied. We have developed models to predict woody-plant naturalization in five local areas within the Upper Midwest (United ...


Evaluation Of Seed-Applied Nematicides In On-Farm Trials, Tristan Mueller, Peter Kyveryga Dec 2015

Evaluation Of Seed-Applied Nematicides In On-Farm Trials, Tristan Mueller, Peter Kyveryga

Proceedings of the Integrated Crop Management Conference

Soybean cyst nematodes (SCN) are one of the major soybean yield robbers in Iowa. It was estimated that there was more than 11 million bushels of soybeans lost due to SCN in Iowa just in 2014 (Bradley et al., 2015). The primary management of SCN is with resistant soybean varieties. In recent years there have been several nematicidal seed-treatment products introduced to the market that may provide additional protection from SCN. These products can be classified into two broad categories, chemical and biological. Avicta and ILeVO are two of the primary chemical nematicides. Clariva, VOTiVO and N-HIBIT are some of ...


Tractor And Planter Adjustments To Improve Profitability, Mark Hanna, Dana Schweitzer, Mark Licht Dec 2015

Tractor And Planter Adjustments To Improve Profitability, Mark Hanna, Dana Schweitzer, Mark Licht

Proceedings of the Integrated Crop Management Conference

Reducing operating costs while maintaining productivity and getting the most out of field operations are always important criteria. When grain prices are low, operational savings and improvements directly impact profitability. Field data are shown on tractor and tillage fuel savings strategy and planter closing wheel operation.


Building Soil Health For Sustainable Agriculture Systems, Mahdi Al-Kaisi Dec 2015

Building Soil Health For Sustainable Agriculture Systems, Mahdi Al-Kaisi

Proceedings of the Integrated Crop Management Conference

The benefits of a healthy soil in sustaining crop production are most evident when growing conditions are less than ideal. Healthy soils increase the capacity of crops to withstand weather variability including short term extreme precipitation events and intra-seasonal drought (Al-Kaisi et al., 2013). The extreme drought in 2012 (Rippey, 2012) resulted in variable yield reduction to corn and soybean production in Iowa with the worst impact on fields with conventional tillage systems (i.e., chisel plow, deep ripping, etc.). Increasingly highly variable weather conditions present increased risks to crops and require more careful attention to conservation planning so as ...


Practical Use Of Remote Sensing In Crop Management, Patrick Reeg Dec 2015

Practical Use Of Remote Sensing In Crop Management, Patrick Reeg

Proceedings of the Integrated Crop Management Conference

After attending this session, attendees will gain knowledge on: A background to remote sensing in agriculture; Remote sensing sources and resolution; and On-Farm Network use of remote sensing.


Micronutrient Fertilization For Corn And Soybean, Dorivar Ruiz Diaz Dec 2015

Micronutrient Fertilization For Corn And Soybean, Dorivar Ruiz Diaz

Proceedings of the Integrated Crop Management Conference

Improvements in crop genetics and increased yield potential with a more intensive production system typically involve a greater demand for commercial fertilizers to secure maximum yields. This raises the question about the role of secondary and micronutrient fertilizers to increase yields. Some soil conditions such as high soil pH and low organic matter may also contribute to decrease the supply of micronutrients to crops. Consequently, there is an increasing interest from producers about the potential benefits of micronutrients as complement of their fertilization programs to maximize yields in corn and soybean.


Environmental Performance With Agronomic Management: Raccoon River Watershed Case Study, Anthony Seeman, Christopher S. Jones, Peter Kyveryga, Adam Kiel Dec 2015

Environmental Performance With Agronomic Management: Raccoon River Watershed Case Study, Anthony Seeman, Christopher S. Jones, Peter Kyveryga, Adam Kiel

Proceedings of the Integrated Crop Management Conference

Accurate information about water quality trends in agricultural watersheds is needed to inform agricultural policy and quantify the effectiveness of field and landscape management practices. Several studies predicted the increased conversion of soybean and pasture acres to more corn acres driven by corn ethanol production would increase N losses and river nitrate-nitrogen.


Anthracnose: The Sophisticated Rot, Lisa J. Vaillancourt, Maria Torres, Noushin Ghaffari, Ester Buiate, Scott Schwartz, Charles D. Johnson Dec 2015

Anthracnose: The Sophisticated Rot, Lisa J. Vaillancourt, Maria Torres, Noushin Ghaffari, Ester Buiate, Scott Schwartz, Charles D. Johnson

Proceedings of the Integrated Crop Management Conference

The mold fungus Colletotrichum graminicola causes anthracnose, one of the most economically damaging corn diseases worldwide. Anthracnose can occur either as a stalk rot (ASR), or a leaf blight (ALB) (4; 27). The leaf blight phase is generally insignificant in North America as a cause of yield loss, although in the tropics and subtropics it is much more important. Resistance to ASR is usually not correlated with resistance to ALB, complicating efforts to breed resistant corn varieties (2; 4). Resistance to ASR and ALB is mostly quantitative, although sources of major gene resistance have been described (10; 29). Hybrids containing ...


Forecasting Yields And In-Season Crop-Water Nitrogen Needs Using Simulation Models, Sotirios Archontoulis, Ranae Dietzel, Mike Castellano, Andy Vanloocke, Ken Moore, Laila A. Puntel, Carolina Cordova, Kaitlin Togliatti, Huber Isaiah, Mark Licht Dec 2015

Forecasting Yields And In-Season Crop-Water Nitrogen Needs Using Simulation Models, Sotirios Archontoulis, Ranae Dietzel, Mike Castellano, Andy Vanloocke, Ken Moore, Laila A. Puntel, Carolina Cordova, Kaitlin Togliatti, Huber Isaiah, Mark Licht

Proceedings of the Integrated Crop Management Conference

Forecasting crop yields and water-nitrogen dynamics during the growing cycle of the crops can greatly advance in-season decision making processes. To date, forecasting approaches include the use of statistical or mechanistic simulation models, aerial images, or combinations of these to make the predictions. Different approaches and models have different capabilities, strengths, and limitations. System-level mechanistic simulation models (crop and soil models together) usually offer more prediction and explanatory power at the cost of extensive input data. In contrast, statistical approaches or aerial images can be more robust than mechanistic models but their applicability and prediction/explanatory power is limited. The ...


Making Rational Adjustments To Phosphorus, Potassium, And Lime Application Rates When Crop Prices Are Low And Producers Want To Cut Inputs, Antonio P. Mallarino Dec 2015

Making Rational Adjustments To Phosphorus, Potassium, And Lime Application Rates When Crop Prices Are Low And Producers Want To Cut Inputs, Antonio P. Mallarino

Proceedings of the Integrated Crop Management Conference

Corn and soybean grain prices have been declining and there is considerable uncertainty about the future. It helps somewhat that the prices of phosphorus (P) and potassium (K) fertilizers and lime have remained approximately constant or have declined slightly. Therefore, producers are thinking of reducing fertilizer or lime application rates. There are a few useful things that producers and crop consultants should consider when making fertilization decisions with unfavorable crop/fertilizer price ratios.


Plant Disease Diagnosis Trivia: The Old, The New And The Ugly, Ed Zaworski, Lina M. Rodriguez-Salamanca Dec 2015

Plant Disease Diagnosis Trivia: The Old, The New And The Ugly, Ed Zaworski, Lina M. Rodriguez-Salamanca

Proceedings of the Integrated Crop Management Conference

Every year the plant and insect diagnostic clinic receives many samples of crop disease and insect problems. Some problems can be readily diagnosed in the field or clinic, but there are always those difficult look-a-like diseases, unique disease symptoms on some hybrids and environmental stressors that can be vexing to us all and make accurate diagnosis more difficult. This presentation will help you identify some of these issues in the field and know when it is best to submit a sample to ISU. A majority of the presentation will consist of clicker question activities followed by discussion. We will also ...


Extreme Weather For Crops: Too Dry, Too Wet, And Even Ideal, Elwynn Taylor Dec 2015

Extreme Weather For Crops: Too Dry, Too Wet, And Even Ideal, Elwynn Taylor

Proceedings of the Integrated Crop Management Conference

Corn yield per acre has been more erratic from 2001-2014 than was experienced from 1981-2000. The year to year volatility of soybean yield is similar to that of corn. The consistency of the pattern of favorable and adverse production years indicates that the management of “weather related risk” to production and marketing during the coming decade will likely be increasingly important to farm profits.


Nitrogen Input Decisions With Tight Crop Production Margins, John E. Sawyer Dec 2015

Nitrogen Input Decisions With Tight Crop Production Margins, John E. Sawyer

Proceedings of the Integrated Crop Management Conference

High-yield corn production would not be possible without adequate nitrogen (N) supply. Unless corn follows established alfalfa, N application from fertilizer or manure is almost always needed in Iowa crop rotations with corn following soybean and corn following corn to meet crop demands. This N fertilization need is especially important considering the recent period of high rainfall years in Iowa where residual N is reduced and N response increased. In dry periods, such as the late 1980’s to early 1990’s, there were field situations where no response to applied N would occur, but that has not happened in ...


Incorporating Lessons From High-Input Research Into A Low-Margin Year, D. A. Marburger, B. J. Haverkamp, R. G. Laurenz, J. M. Orlowski, E. Wilson, S. N. Casteel, C. D. Lee, S. Naeve, E. D. Nafziger, K. L. Roozeboom, W. J. Ross, K. D. Thelen, S. P. Conley Dec 2015

Incorporating Lessons From High-Input Research Into A Low-Margin Year, D. A. Marburger, B. J. Haverkamp, R. G. Laurenz, J. M. Orlowski, E. Wilson, S. N. Casteel, C. D. Lee, S. Naeve, E. D. Nafziger, K. L. Roozeboom, W. J. Ross, K. D. Thelen, S. P. Conley

Proceedings of the Integrated Crop Management Conference

Increased soybean commodity prices in recent years have generated interest in developing high-input systems to increase yield. However, little information exists about the effects of input-intensive, high-yield management on soybean yield and profitability, as well as interactions with basic agronomic practices.


Can Herbicides Affect Disease Development? An Overview Of Differentiating Herbicide Injury From Crop Disease And What Is Known About Herbicide Effects On Disease Development, Loren J. Giesler Dec 2015

Can Herbicides Affect Disease Development? An Overview Of Differentiating Herbicide Injury From Crop Disease And What Is Known About Herbicide Effects On Disease Development, Loren J. Giesler

Proceedings of the Integrated Crop Management Conference

With the current changes in weed management and the onset of glyphosate resistant weed species, soybean farmers are using both additional herbicide modes and action and more preplant herbicide options to supplement glyphosate in their weed management programs. In years with conditions favorable for seedling disease and other disease there are typically concerns and inquiries about the cause(s) of symptoms in agronomic plants. Many of the questions focus on differentiating between plant injuries potentially caused by recent herbicide applications versus symptoms caused by plant pathogens.


Integrated Management Of White Mold In Soybean, Damon L. Smith, Jaime Willbur, Medhi Kabbage Dec 2015

Integrated Management Of White Mold In Soybean, Damon L. Smith, Jaime Willbur, Medhi Kabbage

Proceedings of the Integrated Crop Management Conference

Sclerotinia sclerotiorum, the causal agent for white mold (Sclerotinia stem rot), is a devastating soybean fungal pathogen. In 2006, white mold ranked in the top 10 yield reducing diseases of soybean and was estimated to account for over 2 billion metric tonnes of yield loss world-wide (1). In the United States, soybean losses in 2009 reached an estimated 59 million bushels due to white mold, which cost producers ~$560 million (2, 3). Disease control is limited due to the lack of complete resistance in commercial cultivars and an incomplete understanding of resistance mechanisms (3). Further investigation of white mold resistance ...


Corn Disease Update, Alison Robertson Dec 2015

Corn Disease Update, Alison Robertson

Proceedings of the Integrated Crop Management Conference

The 2015 growing season was cooler and wetter than normal. Several foliar diseases were prevalent including northern corn leaf blight, eyespot, southern rust, Goss’s leaf blight, and Physoderma brown spot. Towards the end of the season, stalk quality was poor across the whole state and standability issues occurred. The most prevalent stalk rot was anthracnose, but Physoderma stalk rot, Gibberella and Fusarium stalk rot were reported.


Selecting Corn Hybrids In The Transgenic Era, Joe Lauer, Guanming Shi, Jean-Paul Chavas Dec 2015

Selecting Corn Hybrids In The Transgenic Era, Joe Lauer, Guanming Shi, Jean-Paul Chavas

Proceedings of the Integrated Crop Management Conference

Farmers have adopted biotechnology and genetically engineered (GE) crop technologies quickly. Yield data were analyzed from field experiments over the period 1990-2010 to test the hypothesis that GE corn technologies reduces production risk. GE technology can increase yield, but it also decreases yield for some GE traits. A significant part of the benefits of GE technology comes from protecting corn yield and reducing risk exposure. Gene interactions affect corn productivity through “yield lag” and “yield drag” effects. Often 3 to 4 years are required for new technologies to be equivalent to yields of conventional hybrids.