Although Fusarium is a soil-borne pathogen, it has a life-cycle that infests not only the ground, but potentially all areas, not just of plants, but also boots, gardening tools, and farm equipment.
Different species of Fusarium behave differently, but in general terms there is asexual (mitotic) sporulation, and sexual (melodic) sporulation. Once these spores come into contact with the soil, they affect the roots, producing Fusarium Root-Rot. As they spread up the stem, Fusarium reproduces plugging up vessels, thus constricting the uptake of water and nutrients, resulting in stunted growth and potentially death. Fusarium can reach leaves and buds allowing spores to either fall to the ground or be carried by the wind, infecting the rest of the plantation. Once Fusarium has spread, it’s considered hard or nearly impossible to get rid of it.
BioDox, an aqueous chlorine dioxide, has been tested and applied to what would be considered the full cycle of viral, bacterial and fungal pests with great success and without the common side effects found when using other types of disinfectants, such as, accumulation of toxic chemicals, production of trihalomethane (in the case of chlorinated disinfectants, which chlorine dioxide is not), and resistance over time.
However, the question whether chlorine dioxide is effective against Fusarium specifically comes to the forefront.
In the tests done by W.E. Copes, from the Small Fruit Research Station in Poplarville, MS, G.A. Chastaganer and R.L. Hummel, both from the Puyallup Research Extension Center at the Washington State University in Puyallup, they proved that Chlorine Dioxide solutions are effective under different types of water conditions and qualities, which is one of the problems related to the use of disinfectants (like sodium hypochlorite), which are highly sensitive to pH levels, suspended solids, organic matter, and water hardness in general.
Their study,[1] “Activity of Chlorine Dioxide in a Solution of Ions and pH Against Thielaviopsis basicolaand Fusarium oxysporum,” states the following: “Chlorine dioxide exhibits biocidal activity against a range of organisms, including algae, animal planktons, bacteria, fungi and viruses.”
The effectiveness of the biocidal activity, as mentioned above, will depend on the medium (water quality and characteristics), but they found that:[2]
This research demonstrates the need to adjust the rate of ClO2 according to the demand requirements of the water solution as well as the pathogen and propagule type being targeted. Fungi and types of fungal propagule ranked in order of increasing levels of ClO2 necessary to achieve mortality were: F. oxysporum f. sp. narcissi (conidia) ≤ T. basicola (conidia) << T. basicola (aleurio- spores). The factors that affected activity of ClO2 in the order of decreasing reactivity were concentration of the divalent metal ion solution >> pH > concentration of the nitrogen and hard water solution.
In other words, an adjustment in the concentration, contact time, and type of pathogen is necessary to ensure the effectiveness of Chlorine Dioxide.
Researchers have demonstrated that high biocidal activity was obtained from ClO2 with con- centrations and duration of exposure that ranged from 1 to 9 mg/liter and 1 to 20 min, respectively. For example, a high reduction in viable propagules resulted when conidia or sporangiospores of Botry- tis cinerea, Penicillium expansum, Mucor piriformis, and Cryptosporiopsis peren- nans were exposed to ClO2 at 3 to 5 mg/liter for 1 min, and when Phytophthora cinnamomi, Fusarium oxysporum, Colleto- trichum capsici, Pythium ultimum, and Alternaria zinniae were exposed to ClO2 at 3 mg/liter for 8 min (18,24). These papers demonstrated that concentration of ClO2 varies with time, with an equal mortality of propagules obtained at lower concentra- tions of ClO2 by lengthening the duration of exposure. The upper rate of 9 mg ClO2 per liter is higher than rates commonly used to treat drinking water or in fruit and vegetable dump tanks, where rates of 2 to 5 mg/liter are commonly used.[3]
The good news is that Chlorine Dioxide solutions do, in fact, control and kill various fungal infections, among them Fusarium:[4]
Chlorine dioxide rates needed to achieve LD50 values were similar for conidia of F. oxysporum f. sp. narcissi and T. basicola. Roberts and Reymond (24) noted mortality of Cryptosporiopsis perennans, Mucor piriformis, Penicillium expansum, and Botrytis cinerea spores reached 100.0, 100.0, 99.2, and 93.9%, respectively, from 30 s exposure to 3 mg ClO2 per liter.
This means that different types of fungal infections were easily dealt with (between 93.9% to 100% kill rate) at solutions as low as 3 ppm (parts per million), in a time-period of only 30 seconds of exposure.
The suggested application of BioDox™ goes from 2.5 ppm for preventative root drench, 5 ppm for infection control (with plants in the ground), 25 ppm for soil sterilization (without plants in the ground), 25 ppm for foliar spray on the plants and up to 100 ppm for equipment and surface sterilization, which exceeds by far the tested concentrations as well as times of exposure.
When you try this, you will come to realize that there is indeed an all-round way to control Fusarium (and other fungal, as well as bacterial and viral) infections, without endangering your investment through undesired side-effects.
[1] Copes, W. E., et al. “Activity of Chlorine Dioxide in a Solution of Ions and pH Against Thielaviopsis Basicola and Fusarium Oxysporum.” Plant Disease, vol. 88, no. 2, Feb. 2004, pp. 188–94. DOI.org (Crossref), https://doi.org/10.1094/PDIS.2004.88.2.188
[2] Copes, W. E., et al. This research demonstrates the need to adjust the rate of ClO2 according to the demand requirements of the water solution as well as the pathogen and propagule type being targeted. Fungi and types of fungal propagule ranked in order of increasing levels of ClO2 necessary to achieve mortality were: F. oxysporum f. sp. narcissi (conidia) ≤ T. basicola (conidia) << T. basicola (aleurio- spores). The factors that affected activity of ClO2 in the order of decreasing reactivity were concentration of the divalent metal ion solution >> pH > concentration of the nitrogen and hard water solution.
[3] Copes, W. E., et al.Researchers have demonstrated that high biocidal activity was obtained from ClO2 with con- centrations and duration of exposure that ranged from 1 to 9 mg/liter and 1 to 20 min, respectively. For example, a high reduction in viable propagules resulted when conidia or sporangiospores of Botry- tis cinerea, Penicillium expansum, Mucor piriformis, and Cryptosporiopsis peren- nans were exposed to ClO2 at 3 to 5 mg/liter for 1 min, and when Phytophthora cinnamomi, Fusarium oxysporum, Colleto- trichum capsici, Pythium ultimum, and Alternaria zinniae were exposed to ClO2 at 3 mg/liter for 8 min (18,24). These papers demonstrated that concentration of ClO2 varies with time, with an equal mortality of propagules obtained at lower concentra- tions of ClO2 by lengthening the duration of exposure. The upper rate of 9 mg ClO2 per liter is higher than rates commonly used to treat drinking water or in fruit and vegetable dump tanks, where rates of 2 to 5 mg/liter are commonly used.
[4] Copes, W. E., et al. Chlorine dioxide rates needed to achieve LD50 values were similar for conidia of F. oxysporum f. sp. narcissi and T. basicola. Roberts and Reymond (24) noted mortality of Cryptosporiopsis perennans, Mucor piriformis, Penicillium expansum, and Botrytis cinerea spores reached 100.0, 100.0, 99.2, and 93.9%, respectively, from 30 s exposure to 3 mg ClO2 per liter.
