Soybean field and farmer's hand

Who we are. Why we’re back.

We’re the second SCN Coalition – a diverse group of University researchers, Extension specialists and ag company representatives who are concerned about the evolving threat from soybean cyst nematode. Just like the first SCN Coalition from 1997, we’re encouraging growers to Take the Test. Beat the Pest.

What’s different this time? Because SCN is becoming resistant to the PI 88788 source of resistance (used in more than 90% of resistant varieties), we’re encouraging growers to “Know Your Number” and actively manage SCN. Our goal is to decrease SCN populations and increase yield potential. root-illustration.png

The events that led to the new SCN Coalition

Historical Events

Industry Response


SCN is first discovered in northeast China


SCN is first reported in the scientific literature


SCN is given the scientific name Heterodera glycines by a Japanese scientist


SCN is discovered in the U.S., in North Carolina


First soybean breeding lines with SCN resistance (sources of SCN resistance) are reported: PI 548402 (Peking) and PI 90763


SCN is discovered in the Midwestern U.S., in south-eastern Missouri


PI 88788 is first reported as a source of SCN resistance


Numerous published disease loss estimates dating back to 1974 list SCN as most damaging soybean pathogen


Bedford, the first soybean variety with PI 88788 SCN resistance, is released


SCN is discovered in the upper Midwestern U.S., in southern Minnesota and northern Iowa


SCN is discovered in Ontario, Canada, Michigan, and Wisconsin


First report of SCN causing increased soybean sudden death syndrome (SDS) symptoms and yield loss


A survey of Illinois reveals that about one fourth of SCN infestations have increased reproduction on resistance: the first published evidence that SCN is building up on PI 88788


Criteria for describing soybean varieties as resistant, moderately resistant, moderately susceptible, and susceptible to SCN are published


About half of 1,325 surveyed Midwestern soybean growers indicate it's important to scout for SCN, but 65% have never tested their fields for SCN


The SCN Coalition is organized and launched with funding by the soybean checkoff through the North Central Soybean Research Program (NCSRP)


The SCN Coalition provides training for agronomists and growers, educational materials, advertising, public relations, a website, demonstration plots and offers for free SCN soil sample processing


A follow- up survey of Midwestern U.S. soybean growers two years after the 1997 survey shows 13% more growers say it's important to scout for SCN and 6% more say they have tested for SCN. University SCN testing labs report increases - from 11% to 736% - in numbers of SCN soil samples submitted


The first SCN Coalition ends as funding shifts to breeding for SCN resistance


Standard greenhouse method - the HG type test - for assessing soybean resistance to SCN (SCE08) published


Surveys of Missouri, Illinois, Kentucky, Tennessee, Indiana, and Ontario, Canada, demonstrate that increasing numbers of SCN populations are reproducing at greater levels on PI 88788


First published report of relationship between high SCN and high soil pH in the field


SCN is discovered in Quebec, Canada


An annually updated list of SCN-resistant soybean varieties in the Upper Midwest shows nearly all (>90%) have PI 88788 source of resistance


University, industry, and growers come together to discuss how to avoid another resistance crisis in agriculture similar to the herbicide resistance problem. Their decision: Build a second SCN Coalition


Growers on the NCSRP board approve funds to build the second SCN Coalition. The goal: Increase the number of growers who are testing their fields and actively managing SCN


Analysis of 15 years of experiments in Iowa farmers' fields show an increase in SCN reproduction on PI 88788 and an accompanying decrease in yields of resistant varieties with PI 88788


Growers on the United Soybean Board (USB) approve funds to expand the SCN Coalition's reach to all soybean-producing states


Yield losses will likely continue to worse as SCN reproduction on PI 88788 increases. The SCN Coalition aims to minimize future yield losses