Getting Past Carrot Disease Pressure

Carrot Growers Hindered by Rain Over Winter and Spring

By Patrick Cavanaugh, Farm News Director

Carrot producers from around the world joined together in Bakersfield for the 38th Annual International Carrot Conference. Jeff Harrington is Senior Manager of Ag Operations for Bolthouse Farms, a major fresh carrot producer. He also does seed procurement and agronomy work. He noted that there were presenters from around the world presenting research from the last couple of years.

Jeff Harrington, Bolthouse Farms

“In some cases, they’re going back from the late ’80s, this research that they’ve been doing in regards to disease resistance in carrots, breeding and gnomic markers that they’re finding for these resistances,” Harrington said.

As for pressures impacting California Carrot Growers, Harrington noted, “Of course the recent challenge would be water. Then also disease pressure that’s associated with the excess of water that we’ve had this winter and spring.”

“We have not been able to get into some fields to plant, so we have been hunting around for dry ground all over the state,” Harrington said.

Harrington also discussed some of the problematic pest and diseases that growers often face in the industry. “Definitely it’s nematodes and then cavity spot and alternaria leaf blight,” Harrington said.

Harrington explained how the carrot industry often gets past some of these most troublesome diseases.

“Some varieties have a stronger top that help us with those diseases such as Alternaria. And we are seeing more varieties that are … tolerant to cavity spot some. And then we use soil fumigants that help with against nematode pressure. The fumigants also help with weed pressure,” he said.

Crop Production Service’s Justin Dutra on Pest Control

Justin Dutra on Pest Control

Cal Ag Today recently caught up with Justin Dutra, a crop consultant in pest control for the Hanford branch of Crop Production Services (CPS) to discuss some of the crops he looks after, including, “row crops, dairy crops, cotton, nuts and tree crops.

CPS logo”The staff and management at CPS are focused on providing their customers with the products and services they need to grow the best crops possible,” said Dutra. “They do this by providing an extensive selection of herbicides, insecticides and fungicides that farmers need to keep their crops pest-free.” Dutra reported the  leaffooted bug is causing concern for a few growers in his region.

CPS conducts year-round research and training to order to stay up-to-date on crop protection products and provide their members with accurate information on their use, benefits and limitations. While his region has seen relatively low levels of the leaffooted bug, Dutra noted some other bugs that are worrying growers, such as, “leafhoppers on tomatoes and stink bugs.”

Adult leaffooted bug, Leptoglossus zonatus. Note the two yellow spots on the pronotum behind the head, characteristic of this species. (Photo by David R. Haviland, UC Statewide IPM Program)
Adult leaffooted bug, Leptoglossus zonatus. Note the two yellow spots on the pronotum behind the head, characteristic of this species.
(Photo by David R. Haviland, UC Statewide IPM Program)

The problem with leafhoppers is they puncture the underside of plant leaves and extract much-needed nutrients. Their saliva can cause spotting or yellowing of the leaves and stunting or distortion of the plant. The bigger concern growers have is leafhoppers can also transmit disease. Commenting on the disease that has been most problematic for farmers, Dutra said, “Curly top used to be just a virus you would see every once in a while; now it can wipe out a field.” Dutra noted when they started realizing leafhoppers were becoming a problem two years ago, and again this year, “We are starting to treat for them, and they are beginning to die down now, but they are still there to be reckoned with.”

While the shortage of water has affected growers up and down the state, Dutra noted, “I’m on the East Side and the West Side, and there are more tomatoes coming in on the East Side because of water restrictions on the West Side.”