The specific objective of this proposal is to encourage statewide monitoring for soybean cyst nematode (SCN) by providing funding to offer this service to soybean farmers across NY. Extensive collaborative sampling for this pest from 2014-2017, partially supported by both the NY Corn and Soybean Growers Association and Northern NY Agricultural Development Program, was coordinated by Cornell University and Cornell Cooperative Extension programs. Over the four years of these 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 more widely across NY, we were confident that it was unlikely to be limited to just one field in one county.
In 2019, with funding through NYS Dept. of Agriculture and Markets for a cooperative agricultural pest survey, SCN was confirmed in seven additional fields in six new counties. Funding through your agency and NYS Ag. & Mkts allowed for testing of an additional 104 fields across the state in 2020. Of these fields, 51 tested positive for SCN (49.04%), and positive samples were collected from 29 of 41 total counties tested (70.73%). Since it was first identified in NY in 2016, SCN has been confirmed in 30 counties.

NYS Ag & Mkts and NYCSGA provided funding for another 100 fields to be sampled in 2021. While samples are still being submitted and results are still pending, 50% of samples we’ve submitted so far have tested positive for SCN.
Continued surveillance testing for this pest is critical toward management, as NY soybean growers need to be aware if they have SCN in their fields (and at what severity) so they can stay ahead of the infestation and make integrated management decisions. 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.

1: Project investigators and collaborators will identify soybean growers willing to participate, and 5-10 soybean fields to monitor and sample for SCN testing.
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.
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, 2022:
The soybeans in our region have begun flowering and crops are looking clean for the most part in terms of insect pests and disease. My collaborators have some fields they'd like to continue to monitor and sample for SCN from years past, but are currently identifying other fields that they'd like to sample. We've learned that our sister project was not funded this year (USDA-CAPS, run by NYSDAM), so this NYCSGA-funded SCN sampling effort will be the only large-scale SCN sampling project in soybeans in 2022. Because of this, we are very confident that we will have a high level of participation as farmers are eager to know a) whether they have SCN in their fields, b) how severe their infestation may be, and/or c) what the numbers are in fields that have previously tested positive. Ongoing monitoring is as important as discovering an infestation, because populations can fluctuate and management practices may need to change. One of our fields (in the north country) had a very high SCN population in 2020 (~20,000 eggs/cup of soil), but populations had been reduced to ~5000 eggs/cup in 2021 after the field was rotated into a small grain. That field once again has soybeans in it this year, so we are anxious to see how much the SCN population may have rebounded. By the next update, we should be finished sampling, but results may still be outstanding.

Updated October 30, 2022:
Since the last update, soybean crops are slowly being harvested as weather conditions allow. Most of our collaborators chose to collect samples for SCN testing after harvest, so we have sampled around half of our fields so far (~35), and have submitted 25 for testing. The first 5 sample results have come back already, which were all negative. The remaining 20 samples from this round of submissions should yield results in the coming days, and we expect to finish before the Thanksgiving break. This is the only SCN sampling effort in soybean fields in NY this year, so we are expecting to submit all 75 proposed samples. Several of this year's samples were taken from fields that tested positive in previous years, so we are anxious to learn whether the SCN populations in those fields have changed.

Updated April 29, 2023:
In 2022, soil samples from 66 soybean fields were tested for the presence of soybean cyst nematode, and 15 fields tested positive (23%). We added Erie and Herkimer counties to the map of counties with known SCN populations, and while the population levels of most positive samples were considered to be "low" (<500 eggs per cup of soil), 2 fields in Montgomery county, one field in Herkimer county, and one field in Otsego county fell under the category of "moderate" (500 - 10,000 eggs/cup of soil).
Growers with infested fields were provided with an information sheet providing some context for their SCN number and management options based on their level of infestation. An article promoting this project was published in September 2022 via the Cornell Field Crops blog "What's Cropping Up?", and results were presented to hundreds of growers at regional Crop Congresses around the state, both in-person and online.

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View uploaded report 2

In 2022, soil samples from 66 soybean fields were tested for the presence of soybean cyst nematode, and 15 fields tested positive (23%). We added Erie and Herkimer counties to the map of counties with known SCN populations, and while the population levels of most positive samples were considered to be "low" (<500 eggs per cup of soil), 2 fields in Montgomery county, one field in Herkimer county, and one field in Otsego county fell under the category of "moderate" (500 - 10,000 eggs/cup of soil).
Growers with infested fields were provided with an information sheet providing some context for their SCN number and management options based on their level of infestation. An article promoting this project was published in September 2022 via the Cornell Field Crops blog "What's Cropping Up?", and results were presented to hundreds of growers at regional Crop Congresses around the state, both in-person and online.
This information adds to our understanding of the SCN population in the state. We are finding new infestations every year, and as we continue to sample fields through crop rotations, it allows us to monitor fields with stable or increasing populations over time. More counties are progressing from "low" -level infestations into the "moderate" category, so it will be essential to continue to monitor our statewide infestation to provide growers with the most appropriate and effective management strategies for their unique situations.
In 2023, we will use this information to target fields with moderate and high populations for more in-depth studies into SCN susceptibility to resistant soybean varieties (funded by USDA). Without this ongoing screening project, we would not have the foundational information necessary to target these infestations for more advanced research, and growers would not have the information necessary to manage their infestations efficiently and economically.

Soybean cyst nematode is the number one yield-reducing pest of soybean crops globally and in the US. This pest causes twice the domestic soybean yield loss of any other disease, and since 1996 has caused an average annual loss of $1.5 billion in the US alone. Yield losses of up to 60% have been reported, though losses of up to 30% can occur with no above-ground symptoms. This is a pernicious pest with often subtle or unremarkable above-ground symptoms when they do manifest, so growers may assume that either SCN is not in their fields or that it isn’t a problem until they see widespread symptoms or severe yield reduction.

Compounding the issue are the many other agronomically important soybean diseases that 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 SCN infestations. 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 our monitoring efforts to stay ahead of this pest in NYS, to continue to raise awareness of its threat to crops, and to arm NY soybean growers with information about the SCN populations that may be in their fields.

Now that we have confirmation that SCN has spread throughout the state, not only do we need to identify outbreaks in previously unaffected or untested fields, but we also need to monitor population levels on an ongoing basis to provide relevant and reasonable management recommendations to growers, whether they be specific crop rotations, genetic resistance, nematode protectant seed treatments, or a combination of all three. While populations of SCN in NY have shown thus far to be primarily low to moderate, we have a better chance of managing yield and financial losses by continuing to monitor population levels to keep them in check before they do become unmanageable.