Known Distribution of the Soybean Cyst Nematode, Heterodera glycines, in the United States and Canada, 1954 to 2017

Abstract

The soybean cyst nematode (SCN) is a major yield-reducing pathogen of soybeans in North America. The nematode is an introduced pest and, therefore, knowledge of the distribution of SCN can be helpful in identifying areas where scouting and management efforts should be focused. Such information is especially important because yield-reducing infestations of SCN can occur without obvious above-ground symptoms appearing. In late 2016, nematologists, plant pathologists, and state plant regulatory officials from the soybean-producing states in the United States and provinces in Canada were queried to obtain the latest information on where the nematode had been found. An updated map of the known distribution of SCN in North America was also created. There were 17 states in which SCN was newly found since 2014, when the map was last updated, including the first discovery of SCN in the state of New York. North Dakota was the state with the greatest number of counties, seven, in which SCN had been newly discovered since 2014. This updated information illustrates that the nematode continues to spread throughout the soybean-growing areas of the continent and emphasizes that continued efforts to scout for and manage SCN are warranted.