(Ed. note: On occasion, when bringing to one’s attention the premise that polluted air can damage human health as well as having the potential to cause death in living, breathing beings, there were also times when I said air pollution can be detrimental to crop, plant and tree health. In the Vegetable Growers News article excerpt presented below, both relevant and substantive information is provided, not only regarding the impact wildfire smoke can have on potato crop health, but also how that might affect potato crop growth. Disclosure: Though, in the original, unabridged article, two presenters’ names were mentioned, as it applies to today’s Air Quality Matters blog discussion, referenced exclusively is Carrie Wohleb, a Washington State University associate professor and potato, vegetable and seed Extension specialist, whom, it should be noted gave a presentation at the 2022 Idaho Potato Conference where she addressed concerns – both present and future – and detailed steps potato growers can take to help circumvent certain negative impacts – as well as to point out potential positive effects – to potato crops exposed to wildfire smoke).
Where there’s smoke, there’s usually fire, and that’s certainly been the case in the Western U.S. in recent years.
The increasing number of Western wildfires – which cause smoke and higher levels of ozone pollution – along with Pacific Northwest (PNW) heat waves and reports of a megadrought have farmers facing an ongoing agricultural crisis of global dimensions.
At the 2022 Idaho Potato Conference, … Wohleb addressed present and future concerns and measures to be taken by potato growers facing these ever-increasing natural disasters during the growing season.
Wohleb, … addressed the potential impact of wildfire smoke, residue and ozone pollution on potato crop development in the PNW.
“Wildfires are a problem because they release a large amount of carbon dioxide, brown carbon and black carbon particles and ozone precursors, like hydrocarbons that when they mix with the air form ozone,” Wohleb said.
Ozone is one of the more damaging or harmful pollutants for plants, she added. “It enters the stomata or the pores on the leaves surfaces during normal gas exchange processes of the plant or taking in CO2 and then once inside it forms reactive oxygen species that can damage cell contents and cell membranes.”
Long-term exposure to high concentrations of ozone may result in leaf and plant cell damage. While chronic exposure to moderate or lower levels doesn’t seem to cause visible injury to leaves, it may still cause some impairment of plant function and limit plant growth.
Potato plants, for example, tend to show a stippling symptom – small black spots – all over the leaves from ozone exposure.
“New leaves that are produced after the ozone and other pollutants have dissipated can be perfectly normal,” Wohleb said. “This is especially true for indeterminate potato varieties like Russet Burbank, that tend to continue to put on new growth throughout the growing season.”
Whereas plants that have more of a determinate growth pattern and don’t develop more leaves after flowering, such as Russet Norkotah, tend to show more smoke damage.
“In addition to wildfires, ozone can be formed by lightning strikes, Wohleb said. “So, you might see some of those stippling symptoms after a storm.”
She cautioned to be mindful of environmental changes created by smoke combined with weather conditions when managing your crop.
“During smoky haze, for instance, you might find that the crop needs less water and you should irrigate less,” she said.
Smoky conditions sometimes play positive roles in plant development, Wolheb [sic] said.
“The CO2 from smoke is not really a negative factor, and it might even be a positive factor as long as low light from smoke is not limiting photosynthesis first – that’s the law of limiting factors,” she said. “Temperatures are often moderated when there’s smoke. So, for many crops the smoke cover may actually be a positive factor if it helps to cool things down when it would otherwise be really hot out.”
The proximity to wildfires makes a big difference in the impact on the crop.
“The closer you are to those fires, usually the bigger difference it makes,” she said.
By Bill Schaefer. Republished with permission of Vegetable Growers News. Representative link: https://vegetablegrowersnews.com/article/wildfire-worries-ramp-up-in-the-pacific-northwest/
