The specific objective of this project is to encourage statewide monitoring for the soybean cyst nematode, by providing funding to offer this service to soybean farmers across NY. The soybean cyst nematode (SCN) is considered the number one pest of soybeans nationally and globally, causing an estimated 109 million bushels of yield loss in the U.S. in 2017.
Extensive collaborative sampling for this pest from 2014-2017, partially supported by both the NY Corn and Soybean Growers Association (NYCSGA) and Northern NY Agricultural Development Program (NNYADP), was coordinated by Cornell University and Cornell Cooperative Extension programs. Over the four years of the soybean disease surveys, numerous fields in 17 counties were sampled, and one field in Cayuga County was identified as positive for SCN in 2016, albeit at very low levels. Though it was promising that SCN wasn’t identified widely across NY, we were fairly confident that it is very likely in many more than just one field in one county. In 2019, with funding through NYS Dept. of Agriculture and Markets (NYSDAM) for a cooperative agricultural pest survey, SCN was confirmed in seven additional fields in six new counties. Funding through NYCSGA and NYSDAM in 2020 allowed for testing of an additional 100 fields across the state. Results of the 2020 survey revealed an additional 22 counties with fields testing positive for SCN. Continued surveillance testing for this pest is critical toward management. NY soybean growers need to be aware that they are potentially dealing with SCN in their fields in order to stay ahead of it, before it becomes the number one pest of soybean in NY.
All investigators and collaborators will communicate with their respective soybean growers to identify 5-10 soybean fields to monitor and sample for SCN testing within their geographic territories. During the growing season, collaborators will conduct typical scouting of the soybean fields, while paying close attention to areas of the fields that may be most likely to have SCN infestation (compacted areas, flooded areas, areas with stunted plants, areas of the field with sudden death syndrome). If they identify any suspect areas of the fields, they will dig up symptomatic plants to visually inspect roots for presence of SCN cysts. If they find any cysts on roots, they will submit the plant roots and surrounding soil for confirmation of SCN to the SCN Diagnostics testing facility. If they find no cysts, they will make note of the suspect areas within the fields and will return to those areas to collect soil samples post-harvest.
This project is related to the previous soybean disease and nematode surveys funded by NYCSGA (2014, 2020), NNYADP (2014-2017), NYSDAM (2019-2020). These previous surveys led to eight confirmations of SCN in seven NY counties.

KPI #1: Project investigators and collaborators will identify soybean growers willing to participate, and 5-10 soybean fields to monitor and sample for SCN testing.
KPI #2: Project investigators and collaborators will collect soil samples from 5-10 soybean fields at the end of the growing season and submit to SCN Diagnostics Laboratory testing facility.
KPI #3: Results from the testing facility will be shared with growers and summarized for sharing via websites, extension meetings, reports, and articles. Positive test results will be shared with participating growers, and will include extensive educational information and resources on best integrated management practices to minimize losses to this pest.

Updated July 29, 2021:
The PI and collaborators have identified 5-10 fields each from their respective regions for sampling at the end of the soybean season (Sept-Oct). Ideally, while samples may be taken from fields in counties where fields have tested positive in the past, none of these fields will have been sampled previously. Our goal is not only to monitor SCN populations in areas of known infestation, but to identify as-of-yet unknown populations in areas/counties that have either not been sampled previously, or have not yielded SCN-positive samples in the past.

Two collaborators have left CCE since the approval of this project, but the remaining collaborators have agreed to collect samples in their stead (and in their respective region of the state, where applicable).

This year's wet weather has stressed soybean crops in many fields around the state, so it will be interesting to see how these difficult field conditions relate to SCN populations at harvest, when fields will be sampled for this study.

Updated October 28, 2021:
Soybean crops are still being harvested around the state, and our samples are currently being submitted for testing. So far, we have received results for 16 fields, 8 of which have come back positive for SCN. Of these, 3 have yielded eggs counts in the "moderate" range, where yield losses may occur without visible above-ground symptoms.

While sample results are still outstanding, we plan on sharing partial results during an upcoming regional industry webinar hosted by the Atlantic Soybean Council (Nematodes in Atlantic Soybean Production Virtual Webinar, 9:00-12:00 EST November 16, 2021).

Updated January 18, 2022:
In all, eight collaborators submitted soil samples from 56 soybean fields to SCN Diagnostics. Two collaborators left Cornell before the field season, and the remaining collaborators were unable to sample fields in their territories. Another two collaborators were unable to sample fields in their areas as the wet weather caused the soybean crops in their earmarked fields to either fail or be terminated early.

Of the 56 sampled fields, 13 tested positive for SCN (23.2% of fields), including one each in Schenectady and Tioga Counties, where SCN had not previously been identified. Of the 13 SCN-positive fields, nine had populations in the “low” range (<500 SCN eggs/cup of soil), while the remaining four had populations in the “moderate range” (500 - 10,000 eggs/cup). Only one of these fields had been sampled previously, and that field tested in the “high” range last year (<20,000 eggs/cup), was planted into oats this year, and the number dropped into the “moderate” category this year (5,250 eggs/cup).

This year’s results (partial) have been presented by the PI at an in-person grower meeting in Herkimer County, two webinars ("SCN Monitoring and Virulence of SCN Soil Populations in NY", hosted by the Atlantic Soybean Council, Nov. 16; "Invasive Species in NY", hosted by CCE Madison Co, Dec. 10), and the full results are being compiled into an upcoming extension article. Results will be shared by collaborators at the Northwest NY Soybean and Small Grain Congress on Feb 9th, and a poster is being prepared for an upcoming NYSIPM Symposium.

Updated April 29, 2022:
See attached document

View uploaded report

In 2021, 68 soybean fields were tested for soybean cyst nematode (SCN), of which 13 fields tested positive. This is a decrease from last year's rate of positive samples, but it's unrealistic to expect that this represents a decline in SCN overall. After covering most of the state in prior years, we expanded our search into mostly all previously un-sampled soybean fields, and into two previously un-sampled counties, both of which yielded positive samples. Together with fields sampled for a companion study of dry bean fields, SCN was found in an additional 4 counties this year. Soybean cyst nematode has now been detected in 34 of the 45 upstate counties sampled since 2016. Results from this year's study and current management recommendations were shared at 14 extension meetings in NYS, Colorado, and virtually via the University of Delaware. A forthcoming extension article will share 2021's results and promote the project for 2022.

Many agronomically important soybean diseases have been identified as new or expanding in soy production areas across NYS in recent years, including sudden death syndrome, brown stem rot, and northern stem canker. These soilborne diseases, especially sudden death syndrome, are often highly correlated with soybean cyst nematode infestations. SCN is a ‘silent’ yield-robber, capable of causing significant yield losses with minimal above-ground symptoms. Given the potential impact this pest could have on NY soybean production, especially as the associated diseases expand, we feel it is important to continue these monitoring efforts to stay ahead of this pest in NYS. In order to do that, we need to know how widespread it is throughout NY soybean production areas, and at what population levels to provide best management recommendations. By utilizing our network of field crops extension specialists and a reliable testing facility that specializes in this pest, we can cast a broad net for sampling and receive dependable results for our efforts. Despite our ongoing efforts to encourage SCN testing with our soybean growers, adoption of the testing practice has been minimal. This is mostly because growers assume SCN isn’t a problem in NY. Expanded testing will likely yield more positive identifications of SCN infestations across NY acreage, which would in turn help raise awareness among soybean growers about the actual threat of this pest. We are very lucky in NY, compared to other states who have been dealing with SCN for decades, in that we have the opportunity to not allow this pest to become our #1 pest of soybeans. While populations of SCN are thus far identified as low in NY, we have a better chance of managing yield losses with an integrated pest management approach through specific crop rotations, genetic resistance and nematode protectant seed treatments to keep the populations in check before they become unmanageable.