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Aphid-resistant soybean varieties available for Minnesota

by Siddhi Bhusal (Postdoctoral Associate), Anthony Hanson (PhD Student), Aaron Lorenz (Assistant Professor) and Robert Koch (Assistant Professor)

Soybean aphid is a significant pest of soybean in Minnesota. Soybean breeders have developed various soybean varieties that carry aphid-resistance traits, in addition to other promising agronomic characteristics. Aphid-resistant varieties can provide an effective, economical, and more environmentally sustainable means of protecting soybean from soybean aphid. 

A list of commercially available aphid-resistant soybean varieties suitable for Minnesota can be found in:

http://www.extension.umn.edu/agriculture/soybean/pest/soybean-aphid/aphid-resistant-soybean/

Commercially-available aphid-resistant varieties carry a single aphid-resistance gene (i.e., Rag1 or Rag2) or a combination (i.e., pyramid) of the two resistance genes. Pyramiding of two or more aphid-resistance genes in single soybean varieties is underway in several soybean breeding programs…

NDSU and U of M Extension to hold Conservation Tillage Conference in December

by Jodi DeJong-Hughes, Extension Educator
University of Minnesota along with North Dakota State University Extension Service, is hosting the 2016 Conservation Tillage Conference on Dec. 13-14 in Fargo, ND.

Family members from the Jorgensen Land & Cattle will be the keynote speakers. This fourth generation, 20,000 acre farm includes a diverse cattle, crop and hunting operation in south central South Dakota. They will discuss how and why soil health, livestock integration and sustainability are the driving forces in their operation.

The schedule includes an extensive variety of speakers, drawing on experienced growers, agronomists and academic experts. Whether a novice crop consultant or experienced in conservation tillage, participants will learn about nearly every aspect of improving soil health and productivity.

Topics include residue management, effective use of strip and vertical till, cover crops, extended grazing, soil biology, weed management and fertility in reduced-till system…

Pictorial guide aids in Palmer amaranth and tall waterhemp identification

by Phyllis Bongard and Jeff Gunsolus

With the recent confirmation of Palmer amaranth in Minnesota, it is critical to identify this noxious weed, so it can be eradicated before it becomes widespread. A new pictorial guide compares key characteristics of Palmer amaranth and tall waterhemp at several growth stages throughout the growing season to aid in this identification.
The new guide, “Comparing Palmer Amaranth and Tall Waterhemp – Growth and Development” can be found at http://z.umn.edu/PalmerID. Detailed descriptions also accompany the photos. To access the notes, open the file in Adobe, click on “View,” scroll to “Comment,” then select “Annotations.”

Identification will be the key in reducing further infestation in Minnesota. For other articles on Palmer amaranth, see:
Palmer amaranth in Minnesota: Reporting, preventing further infestation Check pollinator plantings for Palmer amaranth, and Palmer amaranth: A new weed threat to watch out for.

Free Waste Pesticide Collections

Collections available to eleven northwestern Minnesota counties
ST. PAUL, Minn. – The Minnesota Department of Agriculture (MDA) is hosting a series of free waste pesticide collections available to eleven northwestern Minnesota counties. Residents from Beltrami, Cass, Clay, Clearwater, Lake of the Woods, Kittson, Marshall, Pennington, Polk, Red Lake, and Roseau counties may attend any of the four collection sites in mid-August.

Part 5 ----> Just the facts: A review of the biology and economics behind insecticide recommendations

Biology helps determine the profitability of crop production on your farm – Ignoring biology is expensive
None of what we have presented here is new, or groundbreaking information. However, all of what we have presented here is based on science that has been vetted and implemented over thousands of acres for more than a decade. Economic injury levels take commodity prices, labor and control costs into account. Fortunately, the biological components of an EIL are not sensitive to commodity or input prices. The insects on your farm do not eat faster or more when crop prices are high or insecticide costs are low; nor is your crop more sensitive to insect damage (remember the damage boundary). Yield loss occurs at the same level of pest population, regardless of market prices of commodities. It makes no sense to treat if there is no reasonable likelihood of damage.

Science is best when it does not sit still. New research on pest and crop biology and on new management tools may change EIL’s …

Part 4 ----> Just the facts: A review of the biology and economics behind insecticide recommendations

Costs of treating soybean aphids too earlyWhile some newer insecticides target a narrower range of insects, most insecticide applications are not specific. They will kill beneficial insects (lady beetles, parasitic wasps, etc.) as well as pests, later allowing soybean aphid populations to rebound in fields without those beneficial insects to slow them down. By using the ET, natural enemies will have a chance to suppress the aphid population and possibly prevent it from reaching economically damaging levels. After application, insecticide residues will kill insects for a short time, but insecticide activity invariably declines over time (generally, this is considered a good thing). With most insecticides registered for soybean aphid control (such as pyrethroids), soybean foliage emerging after treatment is not protected. Insecticides that are absorbed and translocated within soybean plants typically move upward only a leaf or two and eventually leave unprotected foliage, especially whe…

Part 3 ----> Just the facts: A review of the biology and economics behind insecticide recommendations

Economics of soybean aphid infestations: Math and biology matter


The lowest level of aphid infestation that has been shown to cause yield loss in soybean is several thousand aphid-days. This value, referred to as the damage boundary, is a biological relationship between the insect, crop, and environment, and is independent of crop and input costs. Below the damage boundary, no damage can be measured. Therefore, management efforts directed at treating aphid levels well below the damage boundary cannot provide a return on investment.

The economic injury level (EIL) is the point at which the yield loss from insect damage is equal to the cost of a management action, such as an insecticide application. Insecticide applications made to pest populations that have not reached this point, and are unlikely to reach it, would not provide any return. To more readily apply this yield-loss relationship to field scouting and aphid management, a value in terms of aphids per plant was calculated as the …

Part 2 ----> Just the facts: A review of the biology and economics behind soybean aphid insecticide recommendations

How can soybean aphids reduce soybean yield?The soybean aphid feeds on the phloem fluids (sometimes referred to as "sap") by inserting piercing-sucking mouthparts directly into the phloem vessels that carry products of photosynthesis from the leaves to other parts of the plant. Prior to feeding, aphids "taste" the sap to determine if the plant is a suitable host species and if the quality is acceptable. Once they settle and begin feeding, the injury from soybean aphid infestations can reduce plant growth, pod number, seed number, seed weight and seed oil concentration (2, 24). Early and prolonged aphid infestations can affect all yield components, while later infestations tend to only reduce seed size (2). In addition, soybean aphids decrease photosynthesis rates of soybean plants (11).

Direct yield loss from soybean aphid feeding does not occur when the first (or five or ten) aphids begin feeding. Today’s soybean varieties are equipped to handle minor challenges, i…

Northwest Research and Outreach Center | Crops and Soils Day | Wednesday, July 20, 2016 | Registration @ 7:45

Just the facts: A review of the biology and economics behind soybean aphid recommendations

Before soybean aphid was identified as a pest of soybean in the U.S. in 2000, insecticide applications to northern soybean crops were rare, targeting sporadic insect and mite outbreaks. Although large infestations have been relatively uncommon since the early to mid-2000’s, the soybean aphid is unquestionably still the key insect pest of soybeans in many North Central states. A tremendous amount of research and observational data has been obtained for this pest since its introduction and we have the tools and the knowledge to manage this pest effectively.

The question is where to get the best information? There is a wide array of pest management advice and information available for soybean producers. The internet is particularly rife with newsletters, social media postings, and videos that all purport to give expert advice. It’s wise to always consider the source of the information and also evaluate what it is actually based on - making a statement with absolute certainty doesn’t neces…

Watch for Cereal Aphids in Winter and Spring Wheat / Small Grain Survey Maps for Minnesota and North Dakota

Field reports from Minnesota (MN) indicate that the cereal aphids reported in winter wheat in early May, many of which were treated at the time of herbicide/fungicide applications, are now moving to spring wheat in those southern areas of MN. Surveys are also detecting movement and colonization northward to central and northern HRSW areas of MN. In North Dakota and Minnesota, IPM Scouts are finding these increasing populations, so continue to scout fields for cereal aphid population buildups.

Small Grain Survey maps are now available on a weekly basis and can be accessed for viewing: crop developmentdisease observations, both incidence (% infested plants) and severity (level of infection)insect infestations
Links to the survey maps are at the top of the right column or can be found at:   https://www.ag.ndsu.edu/ndipm/wheat

Weed identification

Whether you are a novice or a veteran, if you need some references for weed identification, here are some resources through University of Minnesota Extension. There are also many references available for your smartphone that you can take to the field.

Got weeds? U of M Extension has resources

Managing herbicide resistance and controlling resistant weeds is a challenge. The U of MN Extension Crops Team is offering new video and web resources to help manage these difficult to control weeds: Weed management website – includes resources on herbicide resistance management, weed identification, herbicide application and chemistry, and research reports.Herbicide resistant waterhemp (video) – Waterhemp has an extended emergence pattern, making it difficult to control. Results from a 2015 trial demonstrating the effectiveness of layering residual herbicides for herbicide-resistant waterhemp control are shown in this video.Herbicide resistant giant ragweed (video series) – Due to its large seed and early emergence, giant ragweed can be difficult to control. This video series describes a study looking at alternative management practices to control this herbicide-resistant weed.
To see additional videos from the U of M Crops Team, visit: https://www.youtube.com/user/UMNCrops.

Cold Temperatures and Burndown Herbicides

byBob Hartzler
     Professor of Agronomy Extension Weed Specialist
     Iowa State University


published April 11, 2016  Integrated Crop Management on line newsletter



ain menu

The weather forecast appears to be favorable for field activities so people will be anxious to get into the field. A concern for many will be the effect of the widespread freeze on the performance of burndown herbicides. Unfortunately, there is no simple blanket statement that can be made since the plant response will vary depending on weed species, weed size, and the herbicides used.

Postemergence herbicides

A statement found on most postemergence herbicide labels is ‘Apply when weeds are actively growing.’ This is by far the most important consideration in determining whether to apply a postemergence product. Most weeds that emerge in March are adapted to sub-freezing temperatures and will not be killed by frost; however, it takes time for them to recover from these events. Performance of herbicides will be reduce…

U of MN researchers seeking soybean growers to cooperate on study of impacts of seed treatments on soybean aphid and parasitic wasps

by Jonathan Dregni (Scientist), Robert Koch (Assistant Professor & Extension Entomologist), and George Heimpel (Professor)

Insecticidal seed treatments are used widely in soybean production. As with any new pest control technology we need to examine the potential for unintended consequences (see more at The Effectiveness of Neonicotinoid Seed Treatments in Soybean). University of Minnesota entomologists are looking for farmer collaborators willing to help study insecticidal seed treatments by allowing researchers to monitor populations of aphids and parasitic wasps in soybean fields planted with insecticide-treated and untreated seeds. Please contact Jonathan Dregni, U of MN scientist, if you or a neighbor would like to be involved, dreg0005@umn.edu or 651-207-3539.

Considerations when planting dicamba-tolerant soybean

by Lisa Behnken, Extension Educator, Fritz Breitenbach, IPM Specialist SE Minnesota, Jeff Gunsolus, Extension Agronomist, Weed Science, and Phyllis Bongard, Content Development and Communications Specialist, University of Minnesota

Monsanto's Roundup Ready 2 Xtend™ soybean, which is tolerant to both glyphosate and dicamba, is available for purchase this spring. While this will eventually offer another option for controlling glyphosate resistant and other tough-to-control weeds, it also brings up label and marketing concerns for the 2016 growing season.

Chomping at the bit yet?

prepared by Jochum Wiersma, UMN Small Grains Specialist
Although there is some snow in the forecast for tomorrow across much of Minnesota, the weather has been unseasonably mild and the frost is already out of the ground in many areas. The first reports of small grain being seeded reached me yesterday and that begged the question whether it is too early the seed small grains. In 2012, the last week of winter and first week of spring were also unseasonable warm. At that time I wrote a short article about the risks and rewards of early planting. Please check back here if you like reread the blog post and refresh your memory.

2016 Private Pesticide Applicator Recertification Workshops

Listing of all workshops

Here are links to the brochures listing dates and locations of workshops by region:

For workshops in Northwest and West Central Minnesota (PDF)

For workshops in Southeast and South Central Minnesota (PDF)

For workshops in Central Minnesota (PDF)
Workshops in Paynesville (1/19), Little Falls (1/21) and Holdingford (2/11) have lunch options - see brochure for details.

For Workshops in Southwest Minnesota (PDF) 


Things to be aware of for private pesticide applicator recertification:

Registration Continues for the 2016 Ag Professional Research Updates

By Dave Nicolai, Coordinator for the Institute for Ag Professionals

The 2016 Ag Professional Research Update Sessions are scheduled for these locations: Waseca (Jan 5), Kasson (Jan 6), Lamberton (Jan 7), Morris (Jan 12), Willmar (Jan 13) and Crookston (Jan 14 ). On-line registration by site is listed below. The registration fee is $45 through Dec 31st and $50 after Jan 1st. Registration will be available at Noon; start time is 12:30 pm. The program continues until 4:40 pm. Please refer to the Institute for Ag Professionals Research Update web page for additional information and registration as well. At the 2016 University of Minnesota Research Update for Ag Professionals, you will find research-based strategies to deal with today's changing pests, diseases, varieties, and nutrient and environmental recommendations. Presentations and discussions at the update will allow you to visit with experienced university researchers and offer you the opportunity to visit with colleagues to di…

New publication on Role of Neonicotinoid Seed Treatments in Soybean Production

by Bob Koch, Extension Entomologist and Bruce Potter, IPM Specialist 

Neonicotinoid seed treatments are used on a large percentage of soybean acres. However, the value of these treatments was questioned in a 2015 EPA report. In response, field crops entomologists from 12 northern states, including Robert Koch and Bruce Potter from the University of Minnesota, collaborated to create a new multipage extension publication, entitled The Effectiveness of Neonicotinoid Seed Treatments in Soybean, which explains the role of neonicotinoid seed treatments in northern soybean. 

Neonicotinoid seed treatments can be a useful tool for management of some early-season soybean pests in targeted high-risk situations. However, the current widespread use of these treatments exceeds the risk posed by pests and may cause adverse consequences, such as impacts to beneficial organisms, such as predatory insects, and lead to development of pest resistance. 

For the full discussion, see The Effectiveness of Neon…