Wednesday, December 16, 2009

Monsanto Addresses Roundup Ready 1 Post Patent Issues

In a recent letter to the American Soybean Association (dated December 15, 2009) Monsanto described their commitment to the Roundup Ready 1 post patent process. It is important to note that this communication did happen after ASA expressed deep concern on how the RR1 trait would be handled once the patent matured. To be clear I have not provided the entire document presented to the ASA but I have provided the exact bullet points that Monsanto offered within this document.

It is confirmed that:

  • All RR1 trait licenses will extend to the end of the term of all applicable patents for which Monsanto has granted licenses. As a results, the last crop year for which Monsanto will collect royalties on the technology is 2014.
  • Licenses have no obligation to destroy or return seed due to expiration of the RR1 trait licenses.
  • Monsanto will not use variety patents against U.S. farmers who save varieties containing the RR1 trait for planting on their own farms after expiration of the RR1 trait patent. Farmers should check with seed suppliers regarding the policy for seed varieties developed by other companies that contain the RR1 trait.
  • Monsanto will maintain full global regulatory support for this first-generation technology for at least three years post patent (i.e., through 2017). This will allow grain from the 2014 crop to be sold and processed. We will continue to monitor and assess the planned use of this first-generation technology beyond 2017 and work with appropriate stakeholders on any extension of regulatory support that may be needed.
  • Seed company licensees who choose to work with RR2Y will be able to continue to sell varieties with RR1 after the patent expires.
For more information please contact the American Soybean Association. If you believe, belong.

Monday, November 30, 2009

Biological Control and White Mold of Soybean

With the wide-spread reports of White mold (or Sclerotinia stem rot, SSR) this year in Wisconsin and across the region, we have been fielding many questions about control options. In particular, many of these questions have been about Contans WG. In this blog, Angie Peltier (Postdoctoral Research Associate in Plant Pathology) and I try to provide information that will help you understand more what biological control for white mold entails.

What is Contans WG?

Contans WG (SipcamAdvan; Durham, NC) is a commercial biocontrol agent and is a proprietary powder formulation that contains the fungus Coniothyrium minitans. Contans WG has been labeled for use in both conventional and organic soybean.

C. minitans was first described in California in 1947, and it is now known to have a world-wide distribution. The host range of C. minitans includes important plant pathogens such as Sclerotinia sclerotiorum, S. trifoliorum, S. minor, and some strains of Botrytis cinerea, B. fabae, and Sclerotium cepivorum (Turner and Tribe, 1976).

How does it work?

The fungus that causes white mold (Sclerotinia sclerotiorum) produces long-lived survival structures called sclerotia that many say resemble rat droppings. Sclerotia are important in the life cycle of Sclerotinia, allowing the fungus to survive in the soil until conditions are favorable for the disease cycle to begin: Upon canopy closure and during periods of cool and wet weather, sclerotia germinate to produce mushroom-like fruiting structures called apothecia. Apothecia produce ascospores that are wind-disseminated. If during a period of leaf wetness ascospores land on dying soybean flower tissue, they can use this food source to gain entry into susceptible soybean plants and cause disease. Many apothecia can emerge from one sclerotium, making each sclerotium an important inoculum source.

When a water suspension of Contans WG is incorporated into the soil, viable spores of C. minitans that come into direct contact with sclerotia, germinate, and then gain entry into the sclerotium by a chemical etching process, eventually causing the disintegration of the sclerotium. Degraded sclerotia cannot produce apothecia, and therefore, these sclerotia produce no inoculum to initiate infection of soybean.

What factors need to be considered for use?

Application timing. Application timing can influence efficacy. While the Contans WG label does not specifically indicate optimal application timing, the manufacturer’s “Directions for Use” (Prophyta, Germany) suggests a minimum of 3 months between application and when SSR disease is likely to develop, to allow adequate time for colonization of sclerotia. Some research suggests that there is a lag time between application and disease suppression. Important consideration: in fields with a high sclerotia load in the soil, enough sclerotia may survive to still cause a substantial level of disease.

Tillage. TheDirections for Use” states that after soil application, the product “should be incorporated as thoroughly and uniformly as possible to a depth of 5 to 20 cm”. An important consideration is also to avoid additional tillage after incorporation, as tillage can bring uncolonized sclerotia to the soil surface.

Some unanswered research questions:

Much of the published data has focused on both aerial and soil application of C. minitans (not Contans WG). Efficacy of C. minitans application has been shown through the reduction of disease in field trials for other crops susceptible to S. sclerotiorum, including dry and snap bean, sunflower and oilseed rape. To date, no research has been published on the use of Contans WG or C. minitans to control white mold in soybean. Therefore, further field research is needed to understand the efficacy of C. minitans in soybean.

In addition, the label directions state that the product must be incorporated into the soil. We are currently examining how efficacy of Contans WG may be impacted under no-till situations.

Lastly, although this issue has not yet been adequately researched, there is some indication that soil type may affect parasitism of sclerotia by C. minitans, which may reduce efficacy in some production situations.

Monday, November 23, 2009

Late Planted Winter Wheat: Growing Slowly But Surely

As with many growers we had a difficult time getting all of our winter wheat planted in the "Optimal" planting date window in 2009. A significant number of winter wheat acres across Wisconsin were planted under the full knowledge of reduced crop insurance coverage as well as reduced yield. Given that the 10-day weather outlook calls for reduced temperatures as well as potential flurries I was interested in the "state" of our November 13th planted winter wheat in Janesville WI. In Image 1. we see that the radicle, seminal roots, and coleoptile have all emerged. In wheat the radicle and seminal roots will be the first structures to appear. Only after the seminal roots and radicle begin to imbibe water will the coleoptile begin to elongate.

Image 1. Wheat development 10 days after planting (November 13th planting date).
For those winter wheat acres that were planted in the last few days remember that winter wheat will vernalize once the radicle emerges from the seed as fall growth will continue as temperatures fall to zero.

Literature referenced: R.J. Cook and R.J. Veseth. 1991. Wheat Health Management.

Tuesday, October 27, 2009

Soybean Harvest in Wisconsin is at a Crawl

Wisconsin growers are struggling to get their soybean crop harvested and we are no exception. As of today the WSRP (WI Soybean Research Program) have only harvested 18% of all of our plots and projected weather outlooks show no real extended harvest window in sight. One of our combine crews just called from Chippewa Falls, WI minutes ago. We opened up the field and were treated with soybean moisture's in the low to mid 20's. Nothing left for us to do but shut it down for the day and hope for some drying weather. As we continue to struggle through harvest soybean seed quality, drying, and storage issues will continue to arise. Below are a few sources of information that may prove useful as harvest pushes forward.

Note of Interest: John Gaska called from the field after the initial post and indicated that all of the pods he inspected remain tightly sealed and no germination was occuring. Grain quality at the Arlington location still looked good to excellent.

Tuesday, October 20, 2009

Drop Dead Date for Seeding Winter Wheat

Given our 7- day weather outlook and the fact that the winter wheat we planted on October 1st is barely spiking it is obvious that the drop dead date for trying to get the rest of our winter wheat planted in 2009 is quickly approaching. Unfortunately assigning a strict calendar date to end planting is difficult given the fact that we don't know what the weather will be like from now until Christmas or the ground freezes (whichever comes first). What we do know is:

  • From our data at our Arlington and Lancaster winter wheat sites we see significant yield loss as planting date is delayed from mid-September to mid-to-late October (Table 1)

Table 1. Planting date effect on grain yield and winter survival at Lancaster and Arlington WI, 2009.

Planting date

Grain Yield

% Yield Loss

Lancaster, WI










Arlington, WI










  • A warm November or December can do wonders. Our winter wheat variety trial was planted at our Janesville location on November 8th 2006 and averaged 76 bu per acre whereas our Arlington site was planted on September 28th 2006 and yielded 78 bu per acre. However given our record cool season I would not mortgage the farm on a warm November/December.

  • If a grower is still planning on planting winter wheat it is likley for reasons other than just yield (i.e. manure ground, straw, setting up a rotation, etc.). To ensure the best possible success given our planting and growing environment:
  1. Plant "new seed
  2. Plant fungicide treated seed
  3. Plant a minimum of 1.75 million seeds per acre (more would be better, up to 2.2 million)

For additional information regarding wheat establishment please see Recommendations for Winter Wheat Establishment in 2009

Thursday, October 15, 2009

The Fall is a Good Time to Pull Soil Samples for SCN

The UW Agronomy Department, in cooperation with the Wisconsin Soybean Marketing Board, is again offering free SCN testing for Wisconsin growers. This program is intended for growers to sample up to three of their fields in order to identify if SCN is present and at what levels. Growers will be responsible for collecting soil from fields suspected to have SCN and then sending the sample to the SCN testing laboratory. They will receive a lab report back with the SCN egg count and a brochure to help plan future rotations and other cultural practices to lower the level of infestation.

We have a limited number of these free kits available and will furnish them on a first come - first served basis. Each kit has a bag and a prepaid mailer for one soil sample which should represent about 10-15 acres. Both the postage and lab fees are prepaid. Before or right after harvest are great times to collect soil samples for routine soil fertility analysis and for SCN monitoring.

Soil sample test kits are available now and can be requested from Colleen Smith at or at 608-262-7702.

Wednesday, October 14, 2009

Preliminary Soybean Yields

Delayed maturity and inclement weather has greatly delayed/slowed our harvest progress. The rain however has given us a chance to get accurate early yield estimates at a few of our sites. Across the seven experiments we have harvested to date soybean grain yield has ranged from 48 (one of our Mn x glyphosate experiments) to 65 bushels (one of our inoculant experiments) per acre. We have only harvested sites near Arlington and Waterloo WI. As soon as it dries out and our beans become harvest ripe we hope to hit the road and begin harvest at our other out-state experimental sites.

Wednesday, September 9, 2009

Yield Loss and White Mold

We have been receiving multiple questions about the potential yield loss in soybean fields where white mold has been observed in 2009. As soybean moves into the R6 and R7 growth stages, this is an excellent time to assess your fields for plant mortality. Measures to consider include incidence, or the percentage of plants showing symptoms of white mold divivided the total number of plants assessed (multiplied by 100 to obtain the percentage). Also, the severity of white mold can be assessed by examining individual plants and rating each plant using a 0-3 scale (Grau et al. 1982), where:

0 = no symptoms
1 = lesions on lateral branches only
2 = lesions on main stem, no wilt, and normal pod development
3 = lesions on main stem resulting in plant death and poor pod fill

As you scout your fields, the more plants that are rated as a 3 would indicate a increased severity of white mold in the field.

What does this all mean in terms of potential yield loss? Previous studies across Wisconsin has indicated that for every 1% plant mortality, yield loss is 0.25-0.50 bushels per acre. So, for example, if there was 10% plant mortality, yield loss may be from 2.5 to 5 bushels per acre.

For further information, a new video available through UW-Extension YouTube discusses symptoms and risk factors associated with white mold.


Grau, C.R., Radke, V.L., and Gillespie, F.L. 1982. Resistance of soybean cultivars to Sclerotinia
sclerotiorum. Plant Dis. 66:506-508.

Wednesday, September 2, 2009

Planting date effect on winter wheat grain yield and winter survival

As we prepare for the 2009/10 winter wheat production year it is good time to reflect back on the problems that we encountered and devise practical solutions that we can integrate into our upcoming field season. The most widespread issue in our 2009 wheat crop was winter-kill. In our field assessments winter survival was impacted by four major factors, three of which growers have direct control over.
  1. The most obvious factor during a drive-by assessment was location within a field. Areas that were sheltered from driving winds as well as areas that held snow such as fence lines or shaded/wooded areas provided protection for crown tissue and increased winter survival.
  2. Planting depth: Variability across a field with no topographical effect was mainly driven by planting depth. Wheat that was planted at less than 0.5 inches demonstrated more winterkill than wheat planted at the 1 inch depth. Please see: (Recommendations for winter wheat establishment in 2009 for more information).
  3. Genetics (winter-hardiness) played a huge role in 2009. Winter survival ratings ranged from 16 to 69% at our Chilton WI variety trial site and 22 to 73% at our Arlington WI variety trial site. For specific information regarding varietal winter survival ratings please see Wisconsin winter wheat performance tests - 2009.
  4. Planting date: Results from our Lancaster and Arlington WI research sites show that yield and winter survival decreased as planting date was delayed (Table 1. and Image 1.). Given the delayed maturity of Wisconsin's field corn and soybean crop and the fact that delayed planting decreases winter survival growers should put greater weight in 2009 on selecting winter-hardy wheat varieties.
Table 1. Planting date effect on grain yield and winter survival at Lancaster and Arlington WI, 2009.
Lancaster, WI
Planting date Grain yield Winter survival (%)
17-Sep 74.9 88.5
30-Sep 68.3 70.0
13-Oct 54.2 58.0
Arlington, WI
Planting date Grain yield Winter survival (%)
18-Sep 101.9 83.8
1-Oct 93.3 55.3
17-Oct 73.9 30.0

Figure 1. Planting date impact on winter survival at Arlington, WI in 2009.

Friday, August 28, 2009

Impact of Cool Temperatures on Soybean Seed Fill

Delayed crop development due to decreased heat units coupled with forecasted cool nighttime temperatures over the next week have many questioning the fate of the WI soybean crop. The soybean fields that I have scouted over the last week range from the R5.5 growth stage to the R6 growth stage (full seed: pod containing a green seed that fills the pod cavity at one of the four upper most nodes on the main stem with a fully developed leaf). The minimum temperature range required for soybean seed ripening is 46.4 to 48.2 °F; whereas the optimal range is 66.2 to 68°F (Holmberg 1973). A survey of the literature suggests that though cool temperatures during grain fill may adversely affect yield, the more serious impact to soybean would likely be increasing the number of days to physiological maturity and the threat of a killing frost (Image 1).

Image 1. Average date for first killing frost in Wisconsin.

On average a soybean plant remains in the R6 growth stage for 18 days; however the range can be as short as 9 days or as many as 30. The risk to WI growers is that the longer we remain below the optimal temperature range for seed development the longer our crop may remain in the R6 growth stage. As we move through the R6 growth stage and into R7 soybean (physiological maturity) seed moisture declines thus decreasing the risk of yield loss due to frost. Judd et al. (1982) found that seed in green pods which contain 65% moisture are injured at 28 °F whereas seed found in brown pods at 35% moisture was not injured at 10 °F.

Though chilling may adversely impact soybean yield a more important issue may be the effect of chilling on seed quality of yellow hilum soybean. Morrison et al. (1998) found that seed coat discoloration in yellow hilum soybean increased with the accumulation of daily minimum temperature ≤ 59 °F during seed development.

Literate cited:

Holmberg S. A. 1973. Soybeans for cool season climates. Agric. Hort. Genet. 31:1-20.

Judd, R., T.M. Tekrony, D. B. Egli, and G.M. White. 1982. Effect of freezing temperatures during soybean seed maturation on seed quality. Agron J. 74:645-650.

Morrison, M. J., L. Pietrzak, and H Voldeng. 1998. Soybean seed coat discoloration in cool-season climates. Agron J. 90:471-474.

Wednesday, August 26, 2009

Sudden Death Syndrome (SDS) and Soybean Cyst Nematode (SCN)

Images and phone calls related to Sudden Death Syndrome (SDS) have been coming into our offices over the last 7-10 days. Many of the suspect fields are being positively diagnosed with SDS. Paul Esker and I walked a field this morning with Matt Hanson, Doge County Crops and Soils Agent, and found a field that was most likely SDS. The symptomology in this field was odd in that it was appearing in small rings across the field and only in certain varieties. Recent literature however has suggested a positive relationship between soybean cyst nematode and SDS. Therefore we would recommend that anyone finding SDS also check for SCN. Remember the WI Soybean Marketing Board provides free testing for SCN for Wisconsin soybean growers. (For more information on this test please click here).

For more information on SDS please refer to the following links.

Monday, August 17, 2009

Soybean Disease Update

Sclerotinia Stem Rot: Over the past week, we have continued to receive numerous questions regarding Sclerotinia stem rot (aka, white mold) and the control of this disease using foliar fungicides. In most soybean fields, we are at the R4 growth stage, or full pod. Fungicides are not recommended at this time for managing white mold. The key point to always remember is that infection by the pathogen that causes Sclerotina stem rot occurred during the flowering period. Sclerotinia stem rot is a monocyclic disease. This means there is only a primary cycle for infection. There is no secondary spread of the disease; although plants that are adjacent or touching an infected plant may become diseased.

Sudden Death Syndrome: Also in the past week, we have also received reports and have seen symptoms associated with Sudden death syndrome (SDS), caused by Fusarium virguliforme. As a reminder, this is a relatively new disease in Wisconsin and the foliar symptoms of SDS can easily be confused with Brown stem rot (BSR) (Figure 1). Symptoms of SDS include a yellow to brown discoloration of the leaves around veins. These often begin as small, circular spots. A differentiating characteristic to BSR us that roots may be black and rotted with a slightly blue hue (growth of the fungus). Conditions in Wisconsin during the 2009 growing season have been favorable since there was ample soil moisture during early vegetative growth in many parts of the state as well as the cool temperatures around flowering.

Figure 1. Images showing symptoms of Brown stem rot (top) and Sudden death syndrome (bottom).