Part 2: The “Sunk Cost Fallacy” in Cultivation:Why Many Growers Avoid Oxidizers in the Root Zone

Why Many Growers Avoid Oxidizers in the Root Zone

Another factor contributing to persistent biofilm and pathogen pressure in cultivation systems is the long-standing caution many growers have toward using oxidizers in the root zone.

Historically, that caution has been understandable with commodity equipment and chemistries that have saturated the market, while creating “The Sunk Cost Fallacy”.

Many oxidizing chemistries used in irrigation sanitation programs have been unstable or difficult to control, creating the potential for concentration spikes that could damage sensitive root tissue. Concerns about phytotoxicity, nutrient disruption, or impacts on beneficial microbes have led many cultivation teams to limit oxidizer use to the front end of irrigation systems, such as incoming water treatment or storage tank sanitation.

In reality, many controlled environment agriculture operators fall into one of two categories:
(1) those who have never used chlorine dioxide, and (2) those who had a bad experience with unstable or poorly controlled chemistries that were initially from wood pulp bleaching and industrial water treatment sectors that leave residual toxic byproducts.

As a result, oxidizers are often kept away from the root zone entirely. But this approach creates a major sanitation blind spot, that PRO-OXINE® Horticulture addresses.

If antimicrobial chemistry does not maintain an effective residual throughout the irrigation system, biofilms and microorganisms can establish in distribution lines, emitters, manifolds, recycled water loops, and the root zone environment. These areas can become microbial reservoirs that continually reintroduce contamination into the crop.

Irrigation infrastructure and biofilms can harbor or transmit plant pathogens and microorganisms such as Pythium, Phytophthora, Fusarium, Ralstonia, Pseudomonas species, Botrytis, and iron bacteria, all of which can contribute to disease pressure or biofilm development in CEA irrigation systems.

And in cannabis and food CEA production environments, irrigation systems and facility surfaces can also serve as vectors for human pathogens such as:

• Escherichia coli
• Salmonella
• Listeria monocytogenes

Combined, these pathogens are capable of triggering product testing failures, destroyed harvests, and costly recalls.