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With the phase-out of methyl bromide due to its impact on ozone depletion, research has focused on developing alternative chemical and biologically based soil disinfestation methods. Anaerobic soil disinfestation (ASD) was developed to control plant-parasitic nematodes, weeds, and soilborne pathogens. However, whether farmers will adopt ASD methods on a large scale is unknown. This study evaluates the economic viability of using ASD in open-field, fresh-market tomato (Solanum lycopersicum) production, drawing on data from field experiments conducted in 2015 in Immokalee, FL, and Citra, FL. The experiment included three treatments: chemical soil fumigation (CSF), ASD1 [the standard ASD treatment with 1482 gal/acre molasses and 9 tons/acre composted poultry litter (CPL)], and ASD0.5 (the reduced rate ASD treatment with 741 gal/acre molasses and 4.5 tons/acre CPL). Results from the economic analysis show that ASD treatments require higher labor costs than CSF regarding land preparation and treatment application. However, yields from ASD treatments are higher than those resulting from CSF, and the improvement in yield was enough to offset the increased labor costs. Relative to CSF, ASD0.5, and ASD1 achieved additional net returns of $630.38/acre and $2770.13/acre, respectively, in Immokalee, FL. However, due to unexpected conditions unrelated to soil treatments, the net return of ASD1 was lower than that of CSF in Citra, FL. Breakeven analysis indicates that ASD treatments would remain favorable even with an increase in the molasses price. However, when the tomato price is low, ASD could potentially lose its advantage over CSF.

About 10,000 ha of staked tomato are grown each year in the winter–spring season in southwest Florida. Tomatoes are produced with transplants, raised beds, polyethylene mulch, drip or seepage irrigation, and intensive fertilization. With the development of nutrient best management practices (BMPs) for vegetable crops and increased competition among water users, N recommendations must ensure economical yields, but still minimize the environmental impact of tomato production. The current University of Florida–IFAS (UF–IFAS) N fertilization rate of 224 kg·ha^-1 (with supplemental fertilizer applications under specified conditions) may require adjustment based on soil type and irrigation system. Because growers should be involved in the development and implementation of BMPs, this project established partnerships with southwest Florida tomato growers. Studies evaluated the effects of N application rates on yield, plant growth, petiole N sap, pests, and diseases. Nine on-farm trials were conducted during the dry winter 2004–05 season. Treatments consisted of N fertilizer rates ranging from 224 to 448 kg·ha^-1, with each trial including at least the UF–IFAS rate and the traditional rate. Although total yields were comparable among N rates, there were differences in size category. Nitrogen rates had little effect on tomato biomass 30 and 60 days after transplanting. Changes in petiole sap NO₃-N and K concentrations were different between seepage and drip irrigation, but usually above the sufficiency threshold. It is important to consider the type of irrigation when managing tomato and determining optimum N fertilizer rates.

Anaerobic soil disinfestation (ASD) is considered a promising sustainable alternative to chemical soil fumigation (CSF), and has been shown to be effective against soilborne diseases, plant-parasitic nematodes, and weeds in several crop production systems. Nevertheless, limited information is available on the effects of ASD on crop yield and quality. Therefore, a field study was conducted on fresh-market tomato (Solanum lycopersicum L.) in two different locations in Florida (Immokalee and Citra), to evaluate and compare the ASD and CSF performances on weed and nematodes control, and on fruit yield and quality. In Immokalee, Pic-Clor 60 (1,3-dichloropropene + chloropicrin) was used as the CSF, whereas in Citra, the CSF was Paldin™ [dimethyl disulfide (DMDS) + chloropicrin]. Anaerobic soil disinfestation treatments were applied using a mix of composted poultry litter (CPL) at the rate of 22 Mg·ha⁻¹, and two rates of molasses [13.9 (ASD1) and 27.7 m³·ha⁻¹ (ASD2)] as a carbon (C) source. In both locations, soil subjected to ASD reached highly anaerobic conditions, and cumulative soil anaerobiosis was 167% and 116% higher in ASD2 plots than in ASD1 plots, in Immokalee and Citra, respectively. In Immokalee, the CSF provided the most significant weed control, but ASD treatments also suppressed weeds enough to prevent an impact on yield. In Citra, all treatments, including the CSF, provided poor weed control relative to the Immokalee site. In both locations, the application of ASD provided a level of root-knot nematode (Meloidogyne sp.) control equivalent to, or more effective than the CSF. In Immokalee, ASD2 and ASD1 plots provided 26.7% and 19.7% higher total marketable yield as compared with CSF plots, respectively. However, in Citra, total marketable yield was unaffected by soil treatments. Tomato fruit quality parameters were not influenced by soil treatments, except for fruit firmness in Immokalee, which was significantly higher in fruits from ASD treatments than in those from CSF soil. Fruit mineral content was similar or higher in ASD plots as compared with CSF. In fresh-market tomato, ASD applied using a mixture of CPL and molasses may be a sustainable alternative to CSF for maintaining or even improving marketable yield and fruit quality.

The success of the best management practices (BMPs) program for vegetables in Florida is measured by the level of BMP implementation and the improvement of water quality. Both require keeping water and fertilizer in the root zone of vegetables. The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Extension Vegetable Group has identified the fundamental principles of 1) basing UF/IFAS production recommendations on the rigors of science and the reality of field production; 2) replacing the out-of-date paradigm “pollute less by reducing nutrient application rates” with “improve water management and adjust fertilizer programs accordingly”; 3) engaging growers, consultants, educators, and regulators in open-channel discussions; and 4) regularly updating current fertilization and irrigation recommendations for vegetables grown in Florida to reflect current varieties used by the industry. The group identified 1) developing ultralow-flow drip irrigation; 2) assisting conversion from seepage to drip irrigation; 3) using recycled water; 4) developing controlled-release fertilizers for vegetables; 5) developing real-time management tools for continuous monitoring of soil water and chemical parameters; 6) developing yield mapping tools for vegetable crops; 7) developing and testing drainage lysimeter designs suitable for in-field load assessment; and 8) using grafting and breeding to develop commercially acceptable varieties with improved nutrient use efficiency by improving morphological, biochemical, and chemical traits as new strategies to keep nutrients in the root zone. These strategies should become funding priorities for state agencies to help the vegetable industry successfully transition into the BMP era.