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Roundup Ready 2 Xtend Soybeans Gain Eu Import Approval (07/28/16)

The European Commission has granted import approval for Roundup Ready 2 Xtend® soybeans which for allows for the import and food/feed use of Roundup Ready 2 Xtend soybeans into the European Union.

Roundup Ready 2 Xtend Soybeans Gain Eu Import Approval

The European Commission has granted import approval for Roundup Ready 2 Xtend® soybeans which for allows for the import and food/feed use of Roundup Ready 2 Xtend soybeans into the European Union. With both the EU and Chinese import approvals and the U.S. Environmental Protection Agency (EPA) in the final stages of review for postemergence, the likelihood of full registration in 2017 is possible.

A full system launch also is planned for Canadian soybean growers in 2017 given the previous Canadian regulatory approval of the herbicide and technology.

Rich Zollinger

Extension Weed Specialist

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Molecular Herbicide Resistance Testing (07/28/16)

This may not apply to most of you but there is molecular testing available to confirm herbicide resistance to herbicides.

Molecular Herbicide Resistance Testing

This may not apply to most of you but there is molecular testing available to confirm herbicide resistance to herbicides.

Purdue:

https://ag.purdue.edu/btny/weedscience/Documents/2016HerbicideResistancescreeningform.pdf

U. of Illinois:

http://web.extension.illinois.edu/plantclinic/downloads/WaterhempFlyer.pdf

PPO resistance has developed in waterhemp in the mid-west and with the preferential use of PPO herbicide for kochia, ragweed, and waterhemp control in ND soybean production there is a high risk of PPO resistant waterhemp and possibly ragweed development in ND.

There are many PPO herbicides registered in soybean and some other broadleaf crops. Some include:

  • Preemergence - Spartan/Authority, Valor, and Sharpen.
  • Postemergence – Ultra Blazer, Cobra, Cadet, Flexstar/Reflex, Vida, and Aim.

Waterhemp and ragweed expansion in ND has not decreased but continues to move west and north in ND. With territory movement there will also likely result in additional herbicide resistance beyond the present ALS and glyphosate resistance. NDSU weed scientists are interested to help confirm new herbicide resistant biotypes. Please contact us if you suspect new resistant types.

Rich Zollinger

Extension Weed Specialist

 

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Why was 2016 a "Bad" Year for IDC in Soybeans? (07/28/16)

One question I have been asked very often over the years is, "Why is the chlorosis so bad this year?"

Why was 2016 a "Bad" Year for IDC IN SOYBEANS?

One question I have been asked very often over the years is, "Why is the chlorosis so bad this year?" Answering this question isn't easy, but it might be helpful to review what we know about the factors that cause and intensify IDC in soybeans.

#1. Calcium carbonate in the topsoil. This is the root of the problem and iron deficiency chlorosis (IDC) cannot occur without carbonates in the root zone. "Lime" in the topsoil buffers the pH of the soil around 8. Soils contain a lot of iron, but iron is much less soluble in the soil solution at a pH of 8 than, say, a pH of 7. The soluble product of carbonates (bicarbonate) neutralizes soybean root surface acidity and in doing so, the activity of the compound that soybean roots exude that make iron a trillion times more soluble is rendered ineffective.

#2. Wetness. If a soil has a seasonal high water table, water cannot flow downwards, and the topsoil will stay wet for extended periods after snowmelt or heavy rain. The main reason this intensifies chlorosis is that wet topsoil containing "lime" will generate a lot of the bicarbonate ion (HCO3-) in the soil solution when the field is wet. The bicarbonate ion is very good at suppressing the solubility of iron, suppressing plant uptake of iron. Plant roots can also take up bicarbonate, and iron can be precipitated within the plant. Wetness can also increase the availability of manganese (Mn2+) in the soil, and this can intensify IDC.

Soybean plants with IDC in North Dakota usually contain very high, sometimes excessive, levels of manganese in the leaves. Fertilizer dealers commonly offer micronutrient "packages" that contain manganese. Save your money, the last thing you need is additional manganese on soils that produce IDC.

#3. Nitrates. Excess nitrate in the soil intensifies IDC in soybeans. Areas in a field that produce severe IDC in soybeans are often less productive for other crops, too. If a farmer fertilizes that field uniformly with nitrogen, it is common for IDC "hot spots" to become, over time, very high in nitrate. Use of cover crops in the fall, or a companion crop of oats or barley planted with the soybeans in the spring may reduce nitrate levels in the soil and decrease surface wetness.

#4. Salinity. Elevated salinity is associated with more intense IDC in soybeans. On level terrain, elevated salinity, like the presence of CaCO3 in the topsoil, is associated with the presence of a water table during at least part of the growing season. The presence of salinity indicates a water table problem, and greenhouse work has shown that just adding the common components of salinity (sodium and magnesium sulfate) can intensify chlorosis. Increased salinity is a major stress on soybeans and the plants are not able to cope with IDC as well.

#5. Your variety may not be as resistant to IDC as the seed company says. It is an educational exercise to look at NDSU's chlorosis ratings each year. Take the five or ten weakest varieties in NDSU's trials, the ones with the worst chlorosis, and look up their IDC ratings on the web sites of the respective seed companies. Give it a try, and draw your own conclusions.

So, why was 2016 a "bad" chlorosis year? Nobody knows for sure, and certainly the weather is variable across the soybean production area of North Dakota. But it does seem that some of the factors listed above were in play. From about June of 2015 until after planting in 2016, the weather was drier than normal. If crop yields in 2015 were reduced by water stress, there may have been higher than normal nitrates in the soil. The long, dry period allowed for upward movement of salts in some soils. In April this year, the visual extent of saline ‘whiteness’ in many fields was astounding. After emergence, significant rain was received in many areas, causing the wetness factor.

The control measures for IDC are well-known.

  • First, select the proper fields for soybeans. Just because soybeans are $10 per bushel and barley might be $3, doesn’t mean that soybeans in a field with high salt and carbonate content will be more profitable. 10 bushel per acre soybeans isn’t profitable at any price, whereas barley at $3 could easily make 70 bushels per acre in the same field.
  • Second, grow a resistant variety. Don't depend on the information from seed dealers alone. Take into consideration the NDSU IDC ratings. Talk to neighbors, ask them which varieties are working.
  • Third, chlorosis seems to be somewhat less severe when the soybeans are planted in wider rows (22 or 30 inch) versus narrow rows (6-7 inch).
  • Fourth consider trying a barley cover crop at soybean planting time. This could be barley broadcast at about a bushel per acre and lightly worked in, or seeded with a two-compartment seeder unit. Kill out the barley when it reaches 3 leaf if dry, and up to 5 leaf if there are wet conditions.
  • Fifth, apply an effective chelate, in-furrow at planting. Two or three pounds per acre of a high-quality FeEDDHA product has proven to alleviate IDC and increase yields, but not with susceptible varieties. An application of FeEDDHA cannot make a susceptible variety grow like a resistant variety. For fields with the worst problems of IDC, use of a resistant variety, cover crop, wider row spacing, and an in-furrow application of an effective chelate are required to yield profitably.


R. Jay Goos

NDSU Soil Science Professor

Dave Franzen

NDSU Extension Soil Specialist



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Nodulation Woes (07/28/16)

There have been a couple calls lately about poorly nodulated soybean in fields that were not previously planted to soybean or have not been planted to soybean in over 10 years.

Nodulation Woes

There have been a couple calls lately about poorly nodulated soybean in fields that were not previously planted to soybean or have not been planted to soybean in over 10 years. The plants are yellow as in the image in this article and when the roots are removed carefully from the soil, there are no nodules, even though the seed was inoculated. Planting into dry soil and the soybean seed lingering under dry conditions for many days is probably to blame for the poor, almost non-existent nodulation. There are patches of greener areas and sometimes green streaks within these fields, but these greener areas are present because there are random areas of the field with higher residual soil N or greater N mineralization activity because these areas have no nodulation either. Even these ‘greener’ areas are not a green as the soybean should be.

At this late stage, much yield has already been lost due to low plant N, but there is still yield to be salvaged with an application of N; up to 100 pounds of N per acre. Do not broadcast liquid as it will severely burn the plants. If liquid must be used, stream it during a calm-wind period. I think granular urea protected with Agrotain/Limus, or another related NBPT product of known NBPT composition would be best.

Unprotected urea with the present soil moisture regime in this heat will quickly lose its ammonia to volatilization, particularly in high pH soil. Rainfall will be necessary for soybean to use the applied N. Do not succumb to the temptation to use ‘high efficiency’ slow release liquid N fertilizers. NDSU research, much conducted personally, shows no efficiency advantage through using these products applied as a foliar treatment compared to UAN.

In the future, it is very important for seed dealers, fertilizer suppliers and consultants to urge their clients to double inoculate new fields of soybean or fields that have been out of soybean for more than 5 years, and particularly if prevent-plant has been in the field past history. Double inoculation could mean granular in the seed furrow and a peat/liquid on the seed, or peat/liquid on the seed. I prefer granular plus something else. This conversation should happen before the customer picks up the seed, rather than the day of planting.

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Dave Franzen

NDSU Extension Soil Specialist

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Pea and Lentil Disease Update (07/28/16)

Scouting of peas and lentils in Burke, Williams, Divide, Mountrail and McKenzie Counties for foliar disease continues as earlier planted crops start to come off the field (Adam Carlson, Crop Scout NDSU).

Pea and Lentil Disease Update

Scouting of peas and lentils in Burke, Williams, Divide, Mountrail and McKenzie Counties for foliar disease continues as earlier planted crops start to come off the field (Adam Carlson, Crop Scout NDSU). In pea, ascochyta blight is commonplace in fields, with the highest incidence found in Mountrail County, but severity levels remain low as they have for most of the season (Fig 1). We are beginning to see white mold in some fields in Williams and Divide Counties, and powdery mildew has been observed in McKenzie County (Fig 1). Bacterial blight has been identified in all pea fields scouted (Fig 1). kalil.1                                                                                                                                                                                    In lentils, ascochyta blight and anthracnose were almost universally present in Divide, Williams and McKenzie Counties but severity levels were low (Fig 2).

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Audrey Kalil

Plant Pathologist

NDSU Williston Research Extension Center

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Estimating Corn Yield before Harvest (07/28/16)

As pollination is finishing throughout the North Dakota corn growing region, we can now make the first estimate of the grain yield potential of a field since the number of ears and number of kernels per ear can be fairly accurately estimated.

Estimating Corn Yield before Harvest

As pollination is finishing throughout the North Dakota corn growing region, we can now make the first estimate of the grain yield potential of a field since the number of ears and number of kernels per ear can be fairly accurately estimated. The only yield component that requires some guess work is kernel size. Of course this whole exercise depends on reasonable growing conditions for the remainder of the season. The process for estimating yield that we describe here is widely used and is proposed due to its simplicity.

The general equation is: ears per acre x kernels per ear divided by a divisor = bushels per acre

  1. Ears per acre: The first step is to determine the number of ears per acre. To do this, count the number of ears that will likely produce an ear at harvest within the length of a row that represents one thousandth of an acre (17.4 feet for 30 inch rows or 23.75 feet for 22 inch rows). Only count the ears that will likely contribute to yield at harvest. Late silking ears on runted plants and ears on tillers should not be counted. In situations where there are multiple ears on a single plant, avoid including the second and third ears unless you feel comfortable in estimating their potential contribution to overall yield.                                                                  (Cont. on next page)
  2. Kernels per ear – to get a good estimate of the number of kernels per ear, count the number of rows and the number of kernels per row from about every five ears in the row that you count to determine ear numbers. Multiply the number of rows by the number of kernels in a row omitting the bottom most kernels and any kernels that did not get fertilized in the tip of the ear. As grain filling progresses, kernels that obviously are not filling did not get fertilized or may have aborted due to stress after fertilization. The kernels on the uppermost portion of the ear in the photo below have not yet been fertilized (silks still attached) and at this point should not be included in the kernel count. Take an average of the kernel numbers per ear for all of the ears that were counted.
  3. Kernel weight divisor – The final factor, which is the least known at this point in the development of the crop, is a factor that estimates seed size. From trials we conducted last year, we propose a kernel weight divisor of 90 (about 280 gms per 1000 kernels). Smaller divisors can be used if you expect kernel size to be larger (using a hybrid that produces large kernels and/or to estimate conditions of exceptionally good grain fill).
  4. An example – if within a 17.4 ft length (assuming a 30-inch spacing) you count an average of 30 ears and the five ears which were counted for kernels numbers had 400, 350, 375, 290, and 380 kernels (average = 359 kernels) then the estimated yield would be (30 x 359)/90 = 120 bu per acre.

This form of yield estimation is just an estimate. Check it with your yield monitor and grain cart scales at the end of a field to confirm its usefulness in the future. It is naturally very hard to capture whole field variability with an estimation using only a small part of a given field.

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Grant Mehring

Assistant Professor of Research

Research Director – MWRPC and NDCUC

Joel Ransom

Extension Agronomist for Cereal Crops


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Mystery Insect (07/28/16)

This week’s mystery insect is a giant ichneumonid wasp called Megarhyssa atrata.

Mystery Insect

This week’s mystery insect is a giant ichneumonid beauzay.1wasp called Megarhyssa atrata. This female was observed on a dead tree near Abercrombie last week. Note the long ovipositor inserted into a hole in the tree. She will lay eggs on the larvae of wood-boring insect larvae, especially pigeon horntail larvae. The wasp larvae will feed on the horntail larvae into the winter and pupate the following spring, with adult emergence beginning in June. Adult females can be up to six inches long, including the length of the ovipositor. While they may look formidable, they are completely harmless.

 

 

 

Patrick Beauzay

State IPM Coordinator

Research Specialist, Extension Entomology

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Scouting Tips for Red Sunflower Seed Weevil (07/28/16)

The USDA NASS reports that 22% of the sunflowers were blooming in North Dakota (USDA NASS News Release – July 25, 2016).

Scouting Tips for Red Sunflower Seed Weevil

The USDA NASS reports that 22% of the sunflowersknodel.7 were blooming in North Dakota (USDA NASS News Release – July 25, 2016). Red sunflower seed weevils (RSSW) are attracted to the first and early blooming sunflower fields, so scouting is critical as the flowers start to open. The 2016 economic threshold (E.T.) for RSSW is calculated at 4-6 weevils per head for oilseed sunflowers and only 1 weevil per head for confection sunflowers. Please see last week’s Crop & Pest Report #12 article for more details on RSSW.

Thank you to those folks who sent in scouting reports on the RSSW. I had reports from Carrington – only 1 weevil per head, and SW ND – 2-4 weevils per head in Hettinger and 10-40 weevils per head near Belfield to New England. We have not found it at our sunflower insecticide trial at Casselton Agronomy Farms. It appears that the SW area of ND has high numbers of RSSW adults now. Peak emergence of RSSWs is usually late July to the first week of August. Another reason why scouting is important now. RSSW will continue to emerge through mid-August.

Scouting should continue until the economic threshold level has been reached or most plants have reached 70% pollen shed (R5.7). At 70% pollen shed, plants are no longer attractive for egg laying or significant damage since shell of sunflower seed is too hard for egg laying.

Insecticide sprays are targeted at adult weevils to prevent egg laying by the females. We recommend that insecticide treatment be considered when RSSW populations are above the E.T. and more than half of the plants in the field are just beginning to show yellow ray petals (R5.1) to 30 percent of the head shedding pollen (R5.3) and the rest of the plants in the field are still in the bud stage. This allows for a window of time to schedule an insecticide application with busy aerial pilots or if adverse weather delays application.

Avoid spraying fields that are predominately in the bud stage. Treatments during the bud stage are not effective because:  (1) seeds have not developed to a stage suitable for egg laying, (2) eggs within the female weevil are not mature, and (3) adult weevil emergence is still continuing. If growers were to spray bud stage sunflower in mid to late July, a second spray may be necessary as more weevils continue to emerge. In our past insecticide trials in oilseed sunflowers, we have always had good to excellent control of RSSW (and banded sunflower moths) with one well-timed insecticide application when >50% of the sunflowers are in the early flowering stages (R5.1 –R5.3).

Janet J. Knodel

Extension Entomologist

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Sunflower Insect Traps (07/28/16)

Pheromone trap catches continue to show high numbers of banded sunflower moths and sunflower moths located in southeast and north central North Dakota (see maps below).

Sunflower Insect Traps

Pheromone trap catches continue to show high numbers of banded sunflower moths and sunflower moths located in southeast and north central North Dakota (see maps below). Scouting is critical during early flowering sunflowers. See Crop & Pest Report #11 for scouting tips on banded sunflower moths and sunflower moths.

(Source: NDSU Extension IPM Crop Survey, funded by USDA NIFA.)

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Janet J. Knodel

Extension Entomologist


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Soybean Aphid Continues to be Low (07/28/16)

About 135 fields were scouted by the NDSU and UMN Crop IPM Scouts for soybean aphids the last two weeks.

Soybean Aphid Continues to be Low

About 135 fields were scouted by the NDSU and UMN Crop IPM Scouts for soybean aphids the last two weeks. Overall, soybean aphid populations continue to be low and below the economic threshold (average of 250 aphids per plants on 80% of the plants and increasing populations). This is probably due to several factors: 1) severe thunder storms washing aphids off plants; 2) beneficial fungi that infect and kill aphids (Moist, humid environments in the soybean canopy favor development of fungal infections.); and 3) hot temperatures above 90F slow soybean aphid growth and reproduction.

The percentage of plant infested by soybean aphids has been increasing in northern RRV, Fergus Falls area, and southwest Minnesota. The IPM crop scouts in North Dakota and Minnesota found soybean aphids in 40% of the soybean fields surveyed (last week was 26%). Percentage of plants infested with soybean aphids ranged from 0 to 90% with an average of 26% of plants infested. Last week’s incidence report was 0 to 77% with an average of 14% plants infested. The average number of soybean aphids per plant ranged from 0 to 29, and increased from last week’s scouting report of 0-10 aphid per plant. We are still below the economic threshold; so, scouting is critical for the next several weeks with slowly increasing soybean aphid counts.

Continue to scouting through R5 (beginning seed). The USDA NASS reports that 81% of the soybeans were blooming (R1), and 36% setting pods in North Dakota (USDA NASS News Release – July 24, 2016).

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Janet J. Knodel

Extension Entomologist

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