Bridging the GAPs: Approaches to Treating Water On Farms

in enzymes and other proteins. PAA irreversibly disrupts enzyme systems, which destroys the microorganism.

Peroxyacetic acid offers several advantages in that it is more resilient to organic matter compared to chlorine and is not as impacted by pH of water when compared to chlorine. However, it has yet to be a commonly used preharvest treatment for biofouling, and the cost of peroxyacetic acid is significantly more than chlorine.

Chlorine is the most widely used antimicrobial for irrigation water. Which of the following statement(s) supports the widespread use of chlorine?

o Chlorine is widely available; in liquid form (sodium hypochlorite), gas form (chlorine gas), and solid form (calcium hypochlorite)

o It is relatively inexpensive compared with other types of antimicrobial pesticides (PAA and chlorine dioxide).

o It targets a broad spectrum of microorganisms, including bacteria, viruses, and parasites

All the above

o

Antimicrobial Devices – Ultraviolet l ight

Electromagnetic radiation is a form of energy all around us and in many forms, including radio waves, microwaves, and X-rays, to name a few. These forms of energy each span an enormous range of wavelengths and frequencies, making up the electromagnetic spectrum. One common form of electromagnetic radiation is ultraviolet (UV) light, which is a component of sunlight. Ultraviolet (UV) light has proven to be an effective technology for the treatment of water, air, and surfaces.

Overview and mechanism of bacterial destruction

UV light can be divided into three categories, UV-A, UV-B, and UV-C, all separated by wavelength. UV-A has the longest wavelength at 320 to 400 nanometers and is responsible for sunburns and commonly associated with skin cancer. UV-B wavelength measures from 280 to 320 nanometers, and is also linked with burning and tanning of skin; however, UV-B is much weaker. The third category, UV-C, has much shorter wavelengths, measuring between 100 and 280 nanometers.

UV-C light is germicidal in that it can kill or inactivate bacteria, viruses, and other microorganisms that could cause infection or disease in plants or humans. In order for UV light to kill microorganisms, the UV rays must

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