Subsurface seep irrigation effects on Omnivorous Nematode vertical distribution in Lysimeters

Authors: Waldo, Benjamin; CROW, WILLIAM - University Of Florida; MENDES, MARIA - University Of Florida

Submitted to: Plant Health Progress
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/19/2023
Publication Date: 4/24/2024
Citation: Waldo, B.D., Crow, W.T., Mendes, M.L. 2024. Subsurface seep irrigation effects on Omnivorous Nematode vertical distribution in Lysimeters. Plant Health Progress. 25(2):185–192. https://doi.org/10.1094/PHP-08-23-0070-RS.
DOI: https://doi.org/10.1094/PHP-08-23-0070-RS

Interpretive Summary: Nematodes are microscopic roundworms that live in soil with plant roots. Most nematodes are beneficial to soil health, but some nematodes feed on plant roots. Nematodes that feed on crop plant roots can injure crop roots and reduce crop yields. In Florida, some farmers irrigate their crops by flooding fields. To determine if this is a factor in nematode abundance in soil, nematode counts from flooded soil and overhead watered soil were performed in a greenhouse environment. Fewer beneficial and plant-feeding nematodes were found in soil watered with flooding than overhead-watered soil. These findings suggest that soil watered by flooding may reduce the number of plant-feeding nematodes as compared with watering from above. Utilizing flooding to manage nematodes may help reduce plant-feeding nematodes in soil without using pesticides. Large scale studies are needed to confirm these findings at the field level.

Technical Abstract: Subsurface seep irrigation is a common practice in Florida histosol soils to supply water to crops by utilizing high water tables. This study evaluated the effect of subsurface and overhead irrigation methods on plant-parasitic and free-living nematode densities in 46 cm soil lysimeters in a greenhouse study. Lysimeters were planted with bahiagrass in 2019 and wheat in 2020 and irrigated with subsurface or overhead irrigation for 12 wks. Nematodes were extracted and quantified at 5 cm depth increments. Nematode counts were subjected to analysis of variance to compare treatment effects. Plant-parasitic and omnivore functional group counts were significantly lower in subsurface irrigated lysimeters. Tylenchorhynchus, Trichodorus, and Mesocriconema counts were significantly lower in subsurface irrigated lysimeters. Hemicyclophora counts were significantly greater in subsurface irrigation treatments at multiple depths and lower at one depth in subsurface irrigation treatments. The results of this study show subsurface irrigation significantly affects nematode density at varying soil depths compared to overhead irrigation in soil lysimeters. Data from this study provide preliminary information on subsurface seep irrigation as a cultural nematode management option in Florida histosols.