YUMA, Ariz. - There are many underlying factors as to what can affect a crop.
In today’s Home Grown, we will learn about a study conducted by the Yuma Center of Excellence for Desert Agriculture.
A study on Fusarium wilt, a microscopic fungus that can literally lie under a lettuce crop, waiting to strike.
As a plant pathologist, Dr. Stephanie Slinski is the expert when it comes to trying to solve wilting lettuce caused by the Fusarium fungus.
For the past year, Slinski has been working closely with farmers affected.
To begin a study like this, researchers must first gather information on what has already been done regarding the fungus.
In the short term, her team has come up with new lettuce varieties to give to farmers, so they can grow them and mitigate the problem in the field.
The problem? Fusarium fungus, may not be harmful to humans but harmful to lettuce.
“It resides in the soil, it likes lettuce, but they can also grow on whatever plant material is actually in the soil. So it can survive for a long period. It infects the lettuce roots, and it causes dieback, so you’ll see yellowing of the outer leaves, and it can stunt the crop and it can make the crop unmarketable,” said Dr. Slinski.
Throughout the study thus far, Slinski learned that some growers have seen this fungus affect their crop in a big way.
“They could see 50 to 100% loss in that field,” said Dr. Slinski.
According to Slinski, the best way to not have a problem with the disease is to prevent it, and that is to use resistant plants.
“We also say tolerant, which means that the fungus can get into roots but you don’t see any symptoms in the plant,” said Dr. Slinski.
During trials, growers that have the fungus in their fields plant different lettuce varieties.
“We evaluate them for how severe the disease symptoms are. So we go out at different times during the season, and we rate the lettuce to see how much yellowing is there how much dieback,” said Dr. Slinski.
Just like in human diseases, there will always be a need for varieties that are resistant to the fungus.
“So if we have a resistant variety, all the growers plant that variety year after year eventually it’s not going to be resistant anymore because this is biology. If you think about diseases of humans, there’s overcoming of antibiotics. So we need to ramp it up and get more tolerant varieties of the field, and find more ways to deal with the disease,” said Dr. Slinski.
The trial will continue until growers can see good solutions.
Slinski will continue to work to come up with resistant lettuce varieties along with groups like UC Davis and the USDA to collect data and release those varieties.