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Latham Hi‑Tech Seeds

Time to Begin Early Crop Scouting

Many Midwest farmers will wrap up the 2011 planting season this week, but there won’t be much rest for the weary. As soon as seed is in the ground, it’s a good idea to start scouting fields.

Post-planting is an ideal time to begin scouting one’s crops. Many soilborne pathogens strike as soon as the seed begins to take on water; others strike young seedlings. Because seeds can germinate quickly and emerge in 3 – 5 days, it’s not too soon to start walking your fields.

Check plant populations, evaluate stands and be on the lookout for early summer diseases. Is there a germination problem? Do you see effects of chilling or crusting?

Assessing your situation ASAP will allow you to formulate a plan while there’s still plenty of time to implement it. You could replant in parts or in all of a field now, so you can attain the yields and returns you want this fall. Information on corn replanting decisions is available from www.agronext.iastate.edu/corn. Click on the “Planting” topic, then click on the “Replant Decision Aid Calculator” tab and use that tool and related information to help make a replant decision. For a resource on soybean replanting decisions, go to www.extension.iastate.edu/publications/pm1851.pdf.

Another benefit of evaluating current stands is to help you determine what adjustments should be made before planting next year’s crop: Do you need to adjust your planter settings or your planting speed?

Once you get past the mechanical issues, look at the disease pressure. If soybeans are damping off, perhaps next season you should opt for seed-applied fungicides? Do you need to pay closer attention to a particular soybean brand or corn hybrid’s disease rating? Seed selection is one of the most important decisions affecting yield. Click here for tips on selecting soybean brands and selecting corn hybrids.

May 12, 2011

Agronomics, Disease, Emergence, Fertility, Fungicide, General, Growth Stages, Insects, Weed Control
Latham Hi‑Tech Seeds

New Tool to ID Soybean Diseases

A colorful, 36-page guide with information on 24 soybean diseases is now available for free – including shipping – through Iowa State University Extension’s online store at www.extension.iastate.edu/store.

“Soybean Diseases” (CSI 0004), gives farmers a comprehensive look at soybean diseases and outlines management options once the disease is identified.

The publication was written by Daren Mueller, Extension specialist; Alison Robertson, plant pathologist; Greg Tylka, nematologist; and Adam Sisson with the ISU Corn and Soybean Initiative. Funding was supplied by the Iowa Soybean Checkoff, Iowa Soybean Association and ISU Extension.

Team Latham

January 25, 2011

Agronomics, Disease, General
Latham Hi‑Tech Seeds

Consider Risk of Soybean Diseases in 2011

Due to the widespread outbreak of Sudden Death Syndrome in 2010, many soybean growers are taking an even closer look to disease rating scores as they select seed for the 2011 growing season. The effects of last season’s disease is fresh on our minds, but industry experts remind growers to recall what happened in their fields two seasons ago if they use a corn-soybean rotation.

“… The risk of white mold should be considered as well, particularly in northern Iowa where white mold was wide spread in 2009,” says X.B. Yang, an Iowa State University Extension plant pathologist and soybean disease expert.

Both SDS and white mold have built a sufficiently high amount of inoculum in soybean fields in Iowa, according to a December 4 article in Wallaces Farmer. Next summer’s weather conditions will help determine which of these diseases has the greater risk of outbreak.

To read more about the risk of SDS and white mold in 2011, click here to read the article in its entirety.

Team Latham

December 7, 2010

Agronomics, Crop, Disease, General, Soybeans
Latham Hi‑Tech Seeds

Fall Tillage Impacts Soybean Diseases

To till or not to till? That’s been one of the most frequently asked questions this fall as many farmers finished harvest 30 days ahead of last year and weather conditions allowed them to work the ground.

Fall tillage practices impact Soybean White Mold and Sudden Death Syndrome, says Iowa State University Plant Pathologist X.B. Yang. The effects of fall tillage are completely opposite: no-till can decrease the risk of White Mold while SDS is usually more severe in no-till fields.

SDS is more severe in no-till situations because soil temperatures remain cooler and wetter, according to a recent Wallaces Farmer article. No-till fields have a lower risk of White Mold, however, due to the placement or distribution of sclerotia.

To read this article in its entirety, click here.

Team Latham

November 23, 2010

Agronomics, Crop, Disease, General, Soil, Soybeans
Latham Hi‑Tech Seeds

SDS: What to watch for and how to choose a soybean brand

In recent blog posts, we’ve mentioned the struggle many Midwest farmers are experiencing with SDS in their soybean fields this year. You may have seen one or two of the videos we’ve posted with Mark Grundmeier, soybean product manager at Latham Hi‑Tech Seeds providing tips on SDS management and prevention.

Below are the final two videos in Mark’s SDS series. In the first video, Mark speaks about what symptoms you should watch for in your fields to help identify SDS, including yellowing or dark blotches on the leaves, and in later stages, dropping leaves.

Symptoms of Sudden Death Syndrome

[youtube]http://www.youtube.com/watch?v=_Sdx4EqpNw4[/youtube]

In the second video, Mark speaks about the importance of variety selection in preventing outbreaks of SDS. Mark recommends finding those brands that have the strongest SDS tolerance, and taking notes about what varieties performed best against the disease in your field if you do experience SDS.

The Best Tolerance Against Sudden Death Syndrome

[youtube]http://www.youtube.com/watch?v=V9_pXGl7y_Y[/youtube]

Did you have any SDS outbreaks in your fields this season? If so, how do you plan to manage these fields in the future?

Team Latham

September 7, 2010

Agronomics, Crop, Disease, General, Soybeans
Latham Hi‑Tech Seeds

Widespread SDS has many asking, “What do I do?”
In last week’s crop report, we highlighted the fact that SDS has been widespread in Iowa and surrounding states. One reason we’re seeing widespread SDS this year is because fields have experienced the perfect storm: soils that were compacted last fall due to a late and wet harvest were also wet and cool during the 2010 planting season. As a result, ideal conditions were created for the soil-borne fungus that causes SDS.

Farmers throughout Latham service areas, including Iowa, Minnesota, Wisconsin, Nebraska, Missouri and South Dakota, have been asking repeatedly, “What should I do?”

Although there isn’t anything you can do right now to minimize the severity of damage from SDS this season, there are multiple management practices you can employ to help ensure SDS doesn’t strike again in the future. Ways to avoid future SDS damage include:
1. Crop rotation – Make sure you don’t plant beans-on-beans in fields that have been hit with SDS. Note fields where SDS is especially prevalent. Crop notes will help you plant a soybean brand with high SDS tolerance in those areas the next time you plant soybeans.
2. Tillage – No-till practices allow soil to remain cooler and wetter longer, which can increase the severity of SDS. Tilling helps change soil conditions to be more adverse to SDS.
3. Planting Date – Planting at a later date can help reduce the risk of SDS, as well.
4. And Variety Selection – Variety selection is incredibly important. Choose soybeans brands that have high SDS tolerance. Latham^® brands that have done very well in SDS-affected soils include the following:
  1. L2085R
  2. L2767R2
  3. L2987L
  4. L2648R2
  5. L2875R
  6. L3268R2
We will follow up with additional blogs on SDS this week. Please feel free to ask any questions you may have about your own fields. Are you seeing SDS in your fields? If so, to what degree?
Team Latham

August 24, 2010

Agronomics, Crop, Disease, General, Soybeans
Latham Hi‑Tech Seeds

Soybean Seedling Diseases

Preventing Soybean Seedling Diseases

The first form of prevention in soybean seedling diseases is to avoid using poor quality seed. Use only high quality seed that isn’t contaminated with fungal pathogens. This will help prevent low germination and increase seedling vigor.

Other factors that could lead to seedling diseases include: inadequate seedbed preparation, compaction, planting too deep, nematode infestations, and high rates of some herbicides.

Scouting, Identifying Seedling Diseases

If scouting reveals stand reduction, it’s important to determine if the cause was a fungal pathogen. Different pathogens are present under different field conditions. The following information can help distinguish which pathogen may be present in your field: general soil temperatures, general soil moisture (saturated, wet or dry), variety resistance or tolerance to Phytophthora, and plant growth stage.

There are three main categories of seedling diseases:

Seed rot occurs during the VO-VE growth stages and may be caused by three pathogens; Pythium, Phytophthora, and Phomopsis. Determining which pathogen caused the seed rot can be difficult. Typical symptoms are soft decay of seed, missing seedlings in the row or poor emergence.

Seedling Mortality (damping-off or seedling blight) occurs during the VE-V4 growth stages. Pythium, Phytophthora, and Rhizoctonia, can cause seedling mortality.

Root or lower stem decay may take place during the seedling stage or may not be apparent until later reproductive stages (VE-Rn). Pathogens that cause root stem decay during the seedling stage are the same as those that cause seedling mortality (above).

Finally, seedling disease symptoms may be confused with herbicide damage, effects of low pH, or other seedling disorders. To help ensure you have a seedling disease problem versus herbicide damage, consider the following: seedling diseases usually occur in irregular patterns that may correspond to changes in soil type. Herbicide damage typically follows a pattern related to the equipment and a group of adjacent plants will be affected.

Source: Monsanto Agronomic Spotlight, photos courtesy of Iowa State University Extension and University of Minnesota extension

Team Latham

May 27, 2010

Agronomics, Disease, General
Latham Hi‑Tech Seeds

Temperature Fluctuations May Inhibit Corn Emergence
Corn planting occurred at an all-time record this spring. In Iowa in particular, we’ve experienced one of the best planting seasons in history. Recent cool temperatures throughout the Corn Belt, however, are requiring extra close attention be paid to corn fields as those cool temperatures may have caused seedling growth problems.

We recommend farmers pay particularly close attention to corn fields planted recently, as they would be the most likely to exhibit seedling rot or poorer emergence. For those in low-lying areas, frost may have been an issue, causing leaf necrsosis and delayed growth of sprouted seeds.

Listed below are seedling growth problems to scout for:
1. Imbibitional chilling damage — the chilling effect seeds may experience when they imbibe, or absorb, water when soil temperatures are less than 55° F for an extended time. Seedlings may “corkscrew” or not emerge when exposed to cool soil temperatures. This may happen also when temperatures swing rapidly by 30° F.
2. Soil crusting — wet soil at planting or heavy rain following planting can lead to reduced plant stands. Significant stand reductions lower yield potential.
3. “Leafing out” underground — occurring most often in crusted soils (also appears with imbibitional chilling, above).
4. Variable plant emergence and reduced plant population. Variable emergence and growth will reduce yield.
Any of the situations listed above could call for a need to replant, but be sure to assess stands before making this decision.

Contact your Latham representative with any questions or click here to read more.
Team Latham

May 18, 2010

Agronomics, Disease, Emergence, General, Season, Spring
Latham Hi‑Tech Seeds

Soybeans at Risk for BPMV

Soybean farmers in 16 Iowa counties may have fields at risk this summer from a soybean virus called bean pod mottle virus (BPMV), according to a model developed at Iowa State University (ISU).

Counties identified by the ISU Pre-Plant BPMV Prediction Model to be at moderate risk are: Cedar, Clinton, Des Moines, Henry, Jefferson, Johnson, Keokuk, Lee, Linn, Louisa, Marion, Muscatine, Osceola, Scott, Wapello and Wayne. All counties but Osceola are located toward the southeast part of the state.

“Soybean growers in those counties are cautioned to use recommended best management practices for bean leaf beetle control to minimize the impact of the disease,” says ISU Plant Pathologist Forrest Nutter.

In counties identified as being at risk, soybean growers should conscientiously scout to detect areas where bean leaf beetle populations may be high enough to warrant mid-season foliar insecticide control measures, noting that early planted soybean fields have higher risk of BPMV incidence.

Those growers in low-risk counties should still scout their fields routinely for bean leaf beetles, as there may have been pockets where the depth and duration of snow cover was sufficient to provide insulation for bean leaf beetles to survive.

Click here for the full release from the Iowa Soybean Association.

Team Latham

May 11, 2010

Agronomics, Disease, General, Season, Spring
Latham Hi‑Tech Seeds

Weak Stalks and Stalk Lodging

I am beginning to get reports that corn is lodging this year. What is particularly alarming is that stalk lodging is occurring in fields with hybrids that typically have very strong stalks. And, even more perplexing, when stalks are split open, they appear to look healthy however the pith is gone right above the node where the stalk lodged over. Many farmers are asking how this can happen.

Typically, weaker stalks result from smaller root systems. This leads to less nutrients going into the plant to satisfy the high demand for carbohydrates of the grain. If the roots bring in less nutrients than the demand of the grain then the grain will pull the carbohydrates it requires from the leaves and stalk. This creates hollowed out pockets above the nodes, which weaken the stalk, and predispose stalks to lodging whenever we get strong winds.

Below, I have put together some talking points that can be helpful in diagnosing weak stalks that may be found in your fields this harvest season.

The most effective management practice at this point in the season is to monitor fields and determine the level of weak stalks in the field. Randomly walk each field and test stalk strength of 50-100 plants by squeezing the stalk at the lower two internodes. If the stalk collapses between the thumb and forefinger of 25 or more plants, weak stalks have advanced to problem levels. These fields are at high risk to wind damage and should be harvested first to decrease lost yield from unharvestable ears.

#1 Wet Spring (late planting, small roots, side-wall compaction, N loss, and poor potassium uptake)
Corn plants have smaller than normal root systems this year. Later planting did not allow the plants time to generate roots that will reach water deep in the soil profile. In addition, when soils are wet, sidewall compaction at planting time can cause nutrient deficiencies later in the season, particularly nitrogen and potassium. We probably lost some applied nitrogen due to wet conditions early. In essence, the plant will do all it can to “pump” carbohydrates into the kernels, sometimes at the expense of the health and maintenance of other plant parts including the roots and lower stalk.

#2 Dry periods (drought) during grain fill
Fields subjected to several weeks without rain will stress the plant and cause the plant to move nutients from the stalk into the ear to fill the grain. This weakens the plant to the point that lodging can occur. Additionally, pathogens can invade and infect the plant causing premature plant death, dropped ears, lightweight grain and encourage the development of stalk rot.

#3 Cooler temperatures and cloudy conditions during grain fill
Cooler temperatures and cloudy days during grain fill can reduce sunlight to the leaf area that provides carbohydrates to the developing kernels. As a result, the corn plant draws reserves from the stalk tissue. The mobilization of nutrients our of the stalk creates hollowed out pockets which weaken stalks and can predispose the plant to stalk rot diseases.

John Latham, President

October 6, 2008

Agronomics, Corn, Crop, Disease

Latham Hi‑Tech Seeds

Time to Begin Early Crop Scouting

Latham Hi‑Tech Seeds

New Tool to ID Soybean Diseases

Latham Hi‑Tech Seeds

Consider Risk of Soybean Diseases in 2011

Latham Hi‑Tech Seeds

Fall Tillage Impacts Soybean Diseases

Latham Hi‑Tech Seeds

SDS: What to watch for and how to choose a soybean brand

Latham Hi‑Tech Seeds

Widespread SDS has many asking, “What do I do?”

Latham Hi‑Tech Seeds

Soybean Seedling Diseases

Latham Hi‑Tech Seeds

Temperature Fluctuations May Inhibit Corn Emergence

Latham Hi‑Tech Seeds

Soybeans at Risk for BPMV

Latham Hi‑Tech Seeds

Weak Stalks and Stalk Lodging