Root Knot Nematode Occurrence Mapped for Midsouth States
It is well known that the soybean cyst nematode [SCN] is a major soybean pest throughout the U.S. However, the root knot nematode [RKN] is becoming a nematode of concern for Midsouth soybean growers. Click here to access a White Paper on this website that provides information about nematodes [including the RKN] that can negatively affect soybeans.
According to a recent report, RKN resulted in the second-most soybean yield loss in the southern U.S. Click here to access results from surveys conducted to estimate soybean yield loss to diseases and nematodes [including RKN] in the midsouthern U.S.
A first line of defense against this increasingly important soybean pest is knowing where it is so that preemptive action can be taken against it if/when necessary. Now there is a new tool that can be used to know where the RKN has been located and where it might pose a production problem for soybean producers. Dr. Travis Faske, a plant pathologist at the Univ. of Arkansas, has played a major role in the development of a map that shows where RKN has been found. Click here to access the map.
Once the map has been accessed, a producer can see in which counties of each state the presence of RKN has been documented. Information in the above-linked White Paper and in a Progressive Farmer/DTN article titled “Southern Root-Knot Nematode Mapped” by Pamela Smith [with quotes from Dr. Faske] will aid producers in choosing control measures that will be necessary if this nematode pest is expected to be a threat to a planned soybean crop.
The RKN map will tell soybean producers whether or not they should be on the lookout for the RKN in a field planned for soybeans. This is especially important since there are no curative control measure for this pest once it has infected soybeans. The only defense is to plant a variety with the best resistance against RKN. Click here for results from RKN variety tests that have been conducted by Dr. Faske and colleagues in Arkansas over the last several years.
Click here for an article on this website that provides information about genetic resistance to RKN that offers a potential defense against this pest. This lends further credence to varietal resistance to this pest being the surest line of defense against its detrimental effect on soybeans.
Composed by Larry G. Heatherly, Aug. 2023, larryh91746@gmail.com