2009 Reports

Developing, Refining and Communicating Soybean Best Management Practices to SD Producers

Gregg Carlson

David Clay

Sharon Clay

Larry Janssen

Peter Sexton

Robert Hall

Executive Summary:

To develop an on farm research program for South Dakota Producers with the goal of continued refinement of production “Best Management Practices”.

Objectives:

To conduct strip-trials and component research designed to answer critical agronomic production questions.

Approach:

à It is our goal to many producers and industry members involved in the on farm research program.

à Our goal for this year is to develop our initial protocols and to get a small number of producers putting out on farm trials.

à We are developing special analysis tools one of which is included in this report.

à We have developed 4 protocols included and are working on several more.

à We have and continue to do the networking necessary to bring on board enough critical mass of on farm studies to significantly improve our BMP recommendations.

Double and Intercropping of Soybeans

Lon Hall

Collaborators:

Rachel Bauer

Steve Kalsbeck

Matt Caron

Rick Geppert

Marci Green

The objective of this research is to investigate the feasibility of double and intercropping soybeans.

Ecology and Management of Soybean Aphid and Other Insect Pests of Soybean

Kelley Tilmon

This report summarizes work conducted (2008 field season) and work in progress (2009 field season) in the SDSU program to study the ecology and management of insect pests of soybean.  My long-term goal for this program is to develop an IPM system for soybean insect pests that minimizes insecticide use and costs, and maximizes the role of natural enemies and resistant soybean varieties.  Such an IPM system will help producers minimize the expense associated with insect pest management in soybean.

Effective soybean disease management practices and soybean disease education for South Dakota

Lawrence Osborne

Kay Ruden

Plant diseases, especially soil-borne diseases such as soybean cyst nematode, Phytophthora root and stem rot, damping-off, and sudden death syndrome are major constraints on soybean production in the region, including South Dakota. However, with proper management tools and techniques, diseases can be controlled or at least tolerated, resulting in significantly greater economic returns than for crops with unmanaged production problems. Furthermore, management of these diseases relies heavily on accurate and timely diagnosis and detection. Through funding from the SDSRPC, the federal government and other sources, the SDSU Diagnostic Clinic and the Extension Plant Pathology projects at SDSU put forth extensive efforts to determine the pathogen profile of soybeans in South Dakota, to establish strong communication with soybean growers and crop managers, and to discover, test, and implement efficient integrated management strategies for several of these important soybean diseases. Soybean disease management in South Dakota is directly related to the cultural management decisions made by producers, especially cultivar selection, crop rotation, prudent tillage and weed management. Fungicides play a limited though important role in responding to in-season foliar diseases and also may serve as preventative management for some soil-borne pathogens such as Phytophthora.

Evaluation of Alternative Production products for Soybeans

Howard Woodard

Anthony Bly

Collaborator:

Robert Berg

Executive Summary:

Seven commercial supplemental products are being evaluated to determine their impact on soybean grain yields for the 2009 growing season.  After grain yields are harvested, statistical evaluations will determine the value of these products for increasing grain yields.

Objectives: Evaluate several seed, soil, and foliar products to determine efficacy in increasing soybean grain yields.

Identification of unexploited QTL alleles from Glycine soja for soybean breeding: I. Pyramiding Genes Enhancing Resistance to Iron Deficiency Chlorosis

Xing-You Gu

Collaborators:

Thomas Schumacher

Catherine Carter

Roy Scott

Soybean varieties developed for North American have a very narrow genetic basis, which makes the crop especially susceptible to existing and new environmental stress factors. The goal of this project is to identify unexploited genes from wild soybean Glycine soja and introduce them into local varieties to enhance their resistance to abiotic/biotic stresses. Our preliminary research in the first two years evaluated >150 lines of wild soybean for major adaptive traits, including duration to maturation, resistance to soybean aphids, and resistance to iron deficiency chlorosis (IDC), made crosses between wild and cultivated soybean lines, and developed an F2 population segregating for the IDC trait. In the past year, we advanced the segregation population for three (i.e., F3, F4, and F5) more generations, repeated the field identification of IDC based on the F3 families, and screened about 600 molecular (soybean microsatellite) markers for polymorphism between the wild and cultivated parental lines. We are continuing to purify the F5 families to obtain a population of F7 recombinant inbred lines (RILs) to map the genes imparting IDC resistance using the polymorphic markers.

Marker Assisted Selection for Soybean

Catherine Carter

Collaborators:

Roy Scott

Marci Green

Kelley Tilmon

Louis Hesler

We have identified new soybean aphid resistance genes in two soybean lines, PI 71506 and PI 230977. The resistance from PI 71506 is due to a single dominant gene, and appears to provide a different kind of resistance  to soybean aphid than that conferred by the currently available resistance gene,  Rag1. The aphid resistance from PI 230977 is due to two or more recessive genes that also differ from Rag1. We have developed segregating populations from crosses of PI71506 and PI 230977 to South Dakota soybean lines, and are mapping these resistance genes to determine their location and identify molecular markers that can be used to develop soybean varieties with improved resistance to the soybean aphid.  We also confirmed markers for improved oil content (higher oleic acid) in soybean.

Plant Viruses Infecting Soybeans in South Dakota

Marie A. C. Langham

Patricia Wieland

Collaborator:

Lawrence Osborne

Production of soybeans in South Dakota is threatened by bean pod mottle virus (BPMV) and soybean mosaic virus (SMV) which each significantly impact soybeans.  However, these viruses may also infect plants simultaneously with greater impacts than each virus. The goals of this research are to (1.) determine if the synergistic effects of dual infection with BPMV and SMV can be utilized as an early generation greenhouse screening tool to evaluate and eliminate susceptible breeding lines, and (2.) to assist with research that is determining the rate of spread of SMV in soybean production fields, the impact of aphid resistant lines on this spread, and the effect of aphid resistant lines on aphid populations in open production fields.

Soybean Breeding and Genetics

Marci Green

Collaborators:

Lawrence Osborne

Catherine Carter

Kelley Tilmon

Thomas Chase

Lon Hall

Executive Summary: The South Dakota State University Soybean Breeding Program continues to grow and change to meet the needs of SD producers. One of the main objectives of the breeding project has been and continues to be release of high yielding soybean varieties adapted to SD environments.  In addition to high yield, released varieties need to have excellent quality characteristics such as high protein and oil as well as resistance to pests including disease, nematodes, and insects.  Quality characteristics are essential not only for domestic markets but also to remain competitive in international markets.  The breeding program has released a number of high yielding conventional lines adapted to SD environment particularly in maturity groups 0 and 1.  We have the opportunity to build on this strong germplasm base to develop soybeans for specialty utilizations.

Objectives: 

A.  Development of high yielding conventional lines with low linolenic (<3%) and ultra low linolenic (<1%) traits.

B.  Development of high yielding conventional lines with mid oleic (>50%).

C.  Development of high yielding conventional lines with ‘low saturate’ trait in combination with ‘low lin’ trait.

D.  Introgression of pest resistance traits into conventional high-yielding and specialty utilization lines. Combine disease resistance such as phytophthora resistance, SCN resistance and aphid resistance with modified fatty acid.

Soybean Pathology

Thomas Chase

Research  for FY 2009 focused on Phytophthora root & stem rot (PRR) and Northern stem canker.  SDSU advance soybean lines were tested for their resistance under field conditions in the Phytophthora nursery.  The majority of lines tested have resistance genes Rps1k and Rps6. Overall disease incidence in the nursery was low, but nonetheless, the lines being tested did as well or better than check varieties. Annual survey for PRR from grower fields was conducted and  cultures were established from infected plants. Work continued on cleanup, purification and race/biotype testing of the P. sojae collection dating back to 1994. The Phytophthora nursery was established for the 2009  field season and will test two new SDSU conventional varieties, Davidson and Deuel. The study will also test effectiveness of mefanoxam seed treatments on all four soybean varieties Plots for Northern stem canker trials were abandoned prior to inoculation due to overwhelming infestation by soybean aphid. A greenhouse based inoculation study was conducted demonstrating that none of the fifteen known PRR resistance genes have any effectiveness against Northern stem canker.

Weed Management Programs: Integration of new soybean genetics and herbicides to manage challenging weed species and diminish selection for glyphosate resistance

Mike Moechnig

Darrell Deneke

Robert Hall

Neal Foster

Dave Vos

Jill Alms

Executive Summary: For the 2009 growing season, five objectives (see below) were targeted to identify the economics and utility of new herbicide resistant soybeans in South Dakota.  Roundup Ready soybeans have been an excellent fit in SD, but over-use of RR soybeans and RR corn is beginning to result in Roundup resistant weeds.  Common ragweed was the first confirmed Roundup resistant weed in SD, and now we are testing a kochia biotype that survived 40 oz/A of Roundup WeatherMax in our first trial.  Additional testing will be needed to confirm resistance.  As Roundup resistant weeds become more common and as seed prices increase, growers may consider alternatives.  Consequently, we established studies at four locations in SD to evaluate conventional (SDSU releases Deuel and Davison), Liberty Link, and Roundup Ready programs for weed control, yield, and economics.  Studies have also been established to evaluate new herbicide resistant crop varieties, such as dicamba resistant soybeans and GAT (glyphosate and ALS-resistant) soybeans.  In addition, studies were established to evaluate interactions between glyphosate and the new soybean herbicide, saflufenacil, as well as herbicides that may be used in the GAT programs.  SDSR&PC provided $11,800, which was matched by $10,060 by SDSU and industry funds, to support the field research, extension/outreach, and publication costs.

Objectives:

1. Compare weed management and the economical returns associated with conventional, Liberty Link, and Roundup Ready soybean weed management programs.  Analysis will include input costs (seed, seed treatments, herbicides, etc.)

2. Compare the yield of conventional, Liberty Link, and Roundup Ready soybeans in variety trials conducted by the Extension Agronomy crop testing program.

3.  Evaluate weed management programs in future soybean varieties, such as dicamba resistant and GAT (glyphosate and ALS-inhibitor tolerant) soybeans.

4. Identify options to make conventional and Liberty Link soybeans more user-friendly for growers.

5.  Conduct educational programs and publish extension literature to bring awareness of the challenges and benefits of new soybean genetics to enable growers to determine the best fit in their operations.