Meloidogyne enterolobii is an introduced root-knot nematode species to North Carolina. This species has a broad host range (including many vegetables, field crops, and weeds) and threatens profitable soybean production in this state by causing severe root galling. The species is more aggressive than the other endemic root-knot nematode species found in North Carolina. Management of this species is difficult, as it appears to increase population densities to damaging levels even with fumigation. Fumigation for general nematode control in soybean are limited due to the costs of application and the limited economic return with their application. Identification of non-fumigant nematicides most effective in reducing nematode damage from this species and protecting soybean profitability in North Carolina is imperative. In addition to identifying resistant varieties, nematodes are frequently managed through cover cropping with non-hosts. Several small grain cover crops have been reported as resistant or non-host to M. enterolobii, however the utility of using cover crops to suppress the nematode is not well understood. This project will repeat trials performed in 2021 that screened several cover crops for their host status to M. enterolobii as well as their effectiveness in suppressing reproduction of the nematode, thus providing a benefit to a following soybean crop.

1.) Screen cover crops grown in NC for their ability to suppress M. enterolobii and quantify the suppressive effect, contributing to a second year of data on this topic
2.) Perform a field trial for assessment of fluopyram-based products applied in-furrow, in combination with a root-knot nematode resistant soybean variety for management of M. enterolobii.
3.) Develop outreach and extension materials related to M. enterolobii and other plant-parasitic nematodes in soybean.

Cover crops that are non-host to M. enterolobii will be identified and their suppressive effect on the nematode quantified. These data will be compared to the outcomes of the cover crop screening performed in 2021 for robust confirmation of results. Data on the use of RKN resistant soybean and fluopyram-containing chemical nematicides for control of M. enterolobii will be generated. This information will summarized into presentations, fact sheets, and other extension communications through NC State University. This project will generate a peer-reviewed publication to share information to the scientific community to support management of Meloidogyne enterolobii and other root-knot nematodes in soybeans.

Plant-parasitic nematodes impact crop production by feeding on plant roots. Root-knot nematodes in particular cause galling on plant roots, compromising water and nutrient uptake by the roots. Nematodes pose a major threat to North Carolina soybean production, due to the costs of controls, local crop rotations favoring their reproduction, and the suitability of the climate to allow for multiple generations per season. Limited control options are available for nematode management. Although host resistance is the most effective and economical nematode control for soybean producers, Meloidogyne enterolobii is known to overcome root-knot nematode resistance previously deployed resistance genes (Ye et al. 2015), and development of new resistant varieties frequently takes many years. In the short term, identifying chemical control options (including non-fumigant nematicides and seed treatments) that are most effective in reducing nematode damage and protecting soybean profitability in North Carolina is imperative. Root-knot nematodes may be managed by planting non-host cover crops. We propose appraising the effectiveness of diverse cover crops to suppress M. enterolobii populations in a greenhouse experiment to narrow the range of cover crop candidates for future field trial evaluations. This trial will replicate one performed in 2021, to provide a robust, repeated dataset. This information will support informed decision making by growers when selecting over crops to use in fields with a history of M. enterolobii.