Soybeans
Field Performance of Thirty-Six Soybean Varieties Marketed as Resistant to Southern Root-knot Nematode, 2022
The southern root-knot nematode (Meloidogyne incognita) is the most yield-limiting plant-pathogenic nematode that affects soybean production in the Mid-South. It is found in nearly all soybean counties in Arkansas. It can cause significant (>70%) grain yield losses when a susceptible variety is used in a field with a high population density of southern root-knot nematode (RKN). Thirty-six commercially available soybean varieties marketed as resistance to the southern RKN were screened. Varieties were divided into 3 experiments (Table 1 to 3) based on maturity group. Varieties were planted in a randomized complete block design with four replications per entry. Plots were planted on 14 June in a field with moderate nematode pressure sampled in the fall. Six root systems were arbitrarily sampled at R5 growth stage from non-harvest rows of each plot to assess southern RKN susceptibility. These results and those on the UA variety testing website can be helpful for variety selection for the 2023 cropping season.
Field performance of soybean varieties from previous trials (2016, 2017, 2018, 2019, 2020, and 2021) can be found on the UA Research Series website.
What else is important: Overall, the percentage of root system galled was lower than in previous years. Therefore, varieties categorized as moderately resistant (MR) can easily be moderately susceptible (MS) when nematode stress and moisture stress are greater. However, selecting a less susceptible variety will yield more than a susceptible one. For example, Progeny 4444 RXS would be expected to have a lower percent root system galled and greater yield than DM48E62S, but not compare to Stine 46EB22 if planted in the same field. Finally, consult the cross-reference guide for soybean varieties to ensure different varieties selected are not the same genetics.
If you have any questions, please contact tfaske@uada.edu.
