Economic evaluation of anaerobic soil disinfestation with varying carbon and nitrogen application rates in open-field organic strawberry production

Authors: DUAN, DINGLIN - University Of Florida; NIAN, YEFAN - Clemson University; XU, NAN - Oregon State University; ZHAO, XIN - University Of Florida; Hong, Jason; Rosskopf, Erin; GAO, ZHIFENG - University Of Florida

Submitted to: HortTechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/7/2025
Publication Date: 8/19/2025
Citation: Duan, D., Nian, Y., Xu, N., Zhao, X., Hong, J.C., Rosskopf, E.N., Gao, Z. 2025. Economic evaluation of anaerobic soil disinfestation with varying carbon and nitrogen application rates in open-field organic strawberry production. HortTechnology. 35(5):674–686. https://doi.org/10.21273/HORTTECH05631-25.
DOI: https://doi.org/10.21273/HORTTECH05631-25

Interpretive Summary: One of the limiting factors for growing crops are soilborne pathogens, nematodes, and weeds. Typically, these biological factors are managed by chemical fumigants, however the most effective chemical fumigant was banned due to being hazardous to the environment and humans. Anaerobic soil disinfestation (ASD) is a biologically based technique for managing these soilborne pathogens, nematodes, and weeds. This is achieved by working in soil amendments, molasses and pasteurized composted poultry litter to the soil, covering the soil with a plastic mulch, and saturating the soil with water. The soil under the plastic becomes anaerobic and during the three-week process and the anoxic conditions and shifts in the microbiome have shown to manage soilborne pathogens, nematodes, and weeds as well as chemical fumigants. This study evaluates ASD in organic production of strawberries over a two-year timespan. The authors found that although ASD has higher upfront costs, the yield and resulting profits were greater for plants grown in ASD treated soil than those grown in non-treated soil.

Technical Abstract: The phaseout of methyl bromide in agricultural production due to its adverse environmental impact has prompted specialty crop industry stakeholders to seek alternative soilborne disease management practices in the US. Anaerobic soil disinfestation (ASD), recognized as a biological and environmentally friendly alternative, is considered a promising practice for managing soilborne pathogens, nematodes, and weeds. However, the economic feasibility of ASD in strawberry (Fragaria x ananassa Duch) production remains under-investigated. This study evaluates the economic viability of ASD using various application rates of carbon and nitrogen fertilizer sources in open-field organic strawberry production. Using field experiment data from production seasons 2022 and 2023 in Citra, FL, this study finds that although ASD treatments incur higher costs, the additional returns from increased yields of some treatments can offset these costs. In particular, using 1,486.0 gal/acre of molasses as the carbon source and 4.2 tons/acre of Everlizer as the nitrogen source in season 2022 produced the highest yield compared to the control group that did not use ASD in production. The same treatment in season 2023 produced the third-highest yield. However, when averaging the yields from both seasons, using 1,145.5 gal/acre of molasses and no Everlizer generated the highest added profit compared to the control group. Sensitivity analysis identified yield as the primary determinant of profit. Meanwhile, the profitability of strawberry production in treatment groups was highly sensitive to fluctuations in both strawberry selling price and molasses price. The result of this study provides crucial information for strawberry producers to determine the economic viability of using ASD in organic crop production systems.