UC Davis Releases 5 Strawberry Varieties Resistant to Deadly Fungal Disease

By Emily C. Dooley

The University of California, Davis, is releasing five new strawberry varieties that are resistant to the soilborne disease Fusarium wilt, have high yields and improved fruit quality.

UC Eclipse, UC Golden Gate, UC Keystone, UC Monarch and UC Surfline will be available for sale to California nurseries from Foundation Plant Services in April.

Roughly 88 percent of strawberries grown in the nation come from California. Fusarium wilt is one of the most common reasons for crop loss and death and yet 55 to 59 precent of cultivars planted in the state since 2014 have not been resistant, according to UC Davis research.

This is the first release from the UC Davis Strawberry Breeding Program where all the cultivars have Fusarium wilt resistance. They are meant to replace susceptible plants on the market such as Monterey, UCD Royal Royce and UCD Valiant.

Monarch was also developed specifically as a prototype for mechanical harvesting – another first out of the breeding program, which dates to the 1930s and has released 72 patented cultivars over the decades.

“These provide the same yield or better and they are Fusarium resistant,” said Steve Knapp, a Distinguished Professor in the Department of Plant Sciences and director of the UC Davis Strawberry Breeding Program. “They have a better collection of traits. They’re superior.”

Dangerous pathogen

Fusarium wilt didn’t present much of a danger to strawberry crops until after the fumigant methyl bromide was phased out of use in the United States in 2005. But the pathogen had always been in the soil, and cases of wilt appeared a year later and increased over time, leading to concerns that a Fusarium wilt pandemic could destroy the crop in California.

“The disease has taken off fast and we need to react quickly to address the need,” said Glenn Cole, a breeder and field manager with the Strawberry Breeding Program.

Knapp said the program tries to “encourage people to consider things like disease resistance” and routinely invites growers and other experts to events showcasing research breakthroughs and improved cultivars.

Varieties for the seasons

The new strawberry varieties each have improved flavor and characteristics that allow for near year-round growing around California, where about 1.8 billion pounds of the fruit are harvested each year. Some of the cultivars are adapted for production in the southern part of the state while others do well under the long daylight hours of summer along the coast.

Eclipse, a “summer plant” cultivar, has the potential to increase grower profitability as it produces in the fall and winter, and yields during research testing were 54 percent higher than similar cultivars. “We expect this cultivar to have wide commercial appeal,” Knapp said. “Eclipse is going to eclipse them all.”

Golden Gate and Keystone are “day neutral.” Those type of cultivars grow throughout the summer on about 60 percent of strawberry farming acres in the state. The “short-day” plants Surfline and Monarch are resistant to Verticillium wilt and Phytophthora crown rot.

Surfline and Eclipse are firmer and promise longer shelf lives. Monarch provides growers with improved fruit qualities relative to other mass-produced cultivars and has characteristics needed for advances in mechanical harvesting, Knapp said.

Genetic tools

Breeding program experts have long been researching ways to improve strawberry cultivars so the crop can withstand pests, disease and other stressors. To find plants that had Fusarium wilt resistance, they obtained the DNA of thousands of plants in field studies. The scientists also developed genetic tools to screen the plants and identify the genes that have resistance to the Fusarium pathogen.

Knowing that information allowed the team to breed resistance into and develop new cultivars, at a faster rate than previous efforts. “These tools have allowed us to sweep out the susceptibility and bring in resistance,” Knapp said.

California Ag Today2023-04-27T08:27:32-07:00April 27th, 2023|

California Strawberry Commission Statement on Pajaro and Salinas River Flooding

California Strawberry Commission President Rick Tomlinson released the following statement regarding the flooding occurring in the Pajaro community and along the Salinas River.

“This week’s flooding events along the Pajaro and Salinas Rivers have been devastating for those communities. Preliminary assessments estimate hundreds of millions in losses and thousands of people displaced in the town of Pajaro. The entire California strawberry industry would like to thank the first responders, aid organizations and volunteers who have helped begin the long recovery process.

We are thankful that the Pajaro River levee breach is being repaired. Stopping the river from flowing into the community is the first priority. This is a good start toward a safer place to live, raise a family, and work.

The foreseeable future will be challenging. Families will work to restore their homes, their jobs, and many other aspects of their lives.

Farms face a massive cleanup. As soon as the cleanup is complete, farmers will begin the process of preparing the fields and starting over.

For the farms that were flooded, this catastrophe hit at the worst possible time. Farmers had borrowed money to prepare the fields and were weeks away from beginning to harvest. Disaster relief and emergency financial assistance will be critical for both the residential community and the farming operations.

California strawberry operations, most of which are multi-generational and family-owned, will remain vital to the damaged areas during the recovery and well beyond.

California’s 400 family strawberry operations create 70,000 jobs in the state and invest 97 cents of every dollar back into the community. That commitment will only grow as the damaged area recovers. Despite the challenges, there will be increased shipments of California strawberries from Oxnard and Santa Maria to stores across the country to keep up with high demand.

Times are tough, but the town of Pajaro, the surrounding communities and the strawberry farming families are more resilient than ever, and we will work together to recover,” said Rick Tomlinson, California Strawberry Commission President.

There are photos available for media use. Plese click here and credit California Strawberry Commission.

California Ag Today2023-03-17T16:16:53-07:00March 17th, 2023|

UC Study Breaks Down Costs of Growing Organic Strawberries

By Pam Kan-Rice, UCANR

Thinking about commercially growing organic strawberries on the Central Coast?

To help prospective and current growers evaluate financial feasibility, the University of California has estimated costs to produce and harvest organic strawberries for fresh market in Santa Cruz, San Benito and Monterey counties.

“This revise of the last cost-of-production study incorporates the newest in labor costs along with updates on cultural techniques,” said study co-author Mark Bolda, UC Cooperative Extension strawberries and caneberries advisor in Santa Cruz, San Benito and Monterey counties.

The new study, “Sample Costs to Produce and Harvest Organic Strawberries in the Central Coast Region-2022,” has been released by UC Agriculture and Natural Resources and UC Davis Department of Agricultural and Resource Economics.

The analysis is based on a hypothetical well-managed organic strawberry farm using practices common to the region, but the costs, materials and practices shown in this study will not apply to all farms. Growers, UC Cooperative Extension farm advisors and specialists, pest control advisers and others provided input and reviewed the methods and findings of the study.

“Current growers can use it as a baseline to compare with their own cost and returns estimates to make sure they have an accurate picture of the profitability of their organic strawberry enterprise,” said co-author Brittney Goodrich, UC Cooperative Extension agricultural economics specialist. “Many agricultural lenders use these studies as a baseline to determine whether to approve operating or investment loan requests from current and potential strawberry growers.”

The researchers assume a farm operation size of 30 contiguous acres of rented land, with strawberries are planted on 27 acres. The study includes a list of suitable strawberry varieties for the region, but no specific variety is used in the study. The crop is harvested by hand and packed into trays containing eight 1-pound clamshells from April through early October, with peak harvest in June through August.

The authors describe the assumptions used to identify current costs for production material inputs and cash and non-cash overhead. Ranging analysis tables show net profits over a range of prices and yields. Other tables show the monthly cash costs, the costs and returns per acre, hourly equipment costs, and the whole farm annual equipment, investment and business overhead costs.

The study’s expanded section on labor includes information on California’s new minimum wage and overtime laws.

“It’s reached a wider audience this time through presentations of the material to students at Cal Poly [San Luis Obispo] and also a group of USDA officials at the California Strawberry Commission,” said Bolda.

“All of this just underlines the value of these studies to California growers and others working in agriculture,” Bolda said.

Free copies of this study and other sample cost of production studies for many commodities are available. To download the cost studies, visit the UC Davis Department of Agricultural and Resource Economics website at https://coststudies.ucdavis.edu.

This cost and returns study was funded by the UC Davis Department of Agricultural and Resource Economics.

For additional information or an explanation of the calculations used in the studies, contact Jeremy Murdock, UC Davis Department of Agricultural and Resource Economics, at jmmurdock@ucdavis.edu or UC Cooperative Extension’s Bolda at (831) 763-8025.

California Ag Today2022-08-26T08:15:47-07:00August 26th, 2022|

Study: New Fumigation Stategy

New Fumigation Techniques for Soilborne Diseases

By Tim Hammerich with the Ag Information Network

Protecting fruit from soilborne pathogens is a big concern for strawberry growers. Researchers at the University of California Ag and Natural Resources are looking to see if a drip application of fungicides might be effective, noted UC Cooperative Extension advisor in entomology and biologicals, Surendra Dara.

“This particular study was based on a request from FMC. They wanted to evaluate if drip application of some fungicides could be supplemental to whatever the growers are currently following to control soilborne diseases. And they also wanted to see if it has any impact on improving the crop health, and potentially other diseases,” said Dara.

Dara noted the results from the first trial were positive, but he didn’t see enough incidence of soilborne disease in the control group to be sure. He’s optimistic though, given drip application of fungicides has been effective on other plant pathogens.

“They do apply fungicides to drip, but not necessarily for soilborne diseases. The management practices are usually obtaining clean transplants and fumigating or crop rotation. These are the typical management recommendations for soil-borne diseases,” explained Dara.

Dara hopes to continue to study the potential for this management practice.

California Ag Today2021-07-23T21:22:40-07:00July 22nd, 2021|

Naturipe Farms Produces Berries for Global Consumers

Naturipe Farms is Leading Growers of Blueberries in the World

By Tim Hammerich, with the Ag Information Network of the West

Naturipe Farms is a brand most Americans have seen in the supermarket. What many may not realize is that the company is actually owned by growers. California Ag Today’s Patrick Cavanaugh recently spoke to Jill Overdorf, who is Naturipe’s Director of Business Development for Food Service & their Corporate Chef.

“Producing fresh berries since 1917, Naturipe Farms is unique to the produce industry with a partnership between four highly esteemed berry growers: Naturipe Berry Growers, MBG Marketing(Michigan Blueberry Growers), Hortifrut, and Munger Companies,” said Orverdorf.

Overdorff said Naturipe is the leading grower of blueberries in the world, second in strawberries, and also produce raspberries, blackberries, avocados, and cranberries.

“Our strawberry growers had a very challenging year, but they developed some great crops,” noted Overdorff. “We also have a good breeding program. Our blueberry growers, the Mungers, are the largest growers of blueberries in California. They had a phenomenal year, and they are branching out and are enormously innovative. They’re leading our value added program with their proprietary wash process, which enables 21 days on a fresh blueberry shelf life for a snack product,” explained Overdorff.

“Our blackberries and raspberries, we have a number of proprietary varieties, including the Centennial Raspberry and the Madeline Blackberry, both flavorful and non traditional berries because of their load seed count and they’re delicious flavor,” she said.

California Ag Today2020-02-01T08:07:49-08:00January 31st, 2020|

Produce Passes All Residue Testing in 2017

FDA Produce Residue Sampling “Once Again” Verifies Safety

Last week the Federal Food and Drug Administration (FDA) released its 2017 pesticide residue sampling data results. FDA concluded: “The latest set of results demonstrate once again that the majority of the foods we test are well below the federal limits set by the Environmental Protection Agency.”

Note the term “once again” in FDA’s statement. They used it because government residue sampling data year after year reaffirms the safety of our food and the exceptionally high level of compliance among farmers with laws and regulations covering the use of organic and conventional pesticides.

Let’s get a little technical for a moment and focus on how FDA residue sampling is protective of consumers. FDA employs a three-fold strategy to enforce the Environmental Protection Agency’s (EPA) tolerances or safety standards for pesticide residues.
If you haven’t heard – September is National Fruit and Vegetable month. Yes, it is time to celebrate the only food group health experts and nutritionists agree we should all eat more of every day for better health and a longer life.
While decades of studies have shown the nutritional benefits of fruits and vegetables are overwhelming and significant, the safety of both organic and conventional produce is also impressive. Government sampling data shows an over 99% compliance rate among farmers with the laws and regulations required for pesticide applications on organic and conventional fruit and vegetable crops. This led the United States Department of Agriculture to state that: “The U.S. food supply is among the safest in the world.”

Many health organizations are promoting National Fruit and Vegetable month to remind consumers about the importance of increasing consumption – only one in 10 of us eat enough of these nutrient-packed foods each day.

However, studies show a growing barrier to consumption is fear-based messaging which inaccurately calls into question the safety of the more affordable and accessible fruits and veggies. This messaging is predominantly carried by the same activist groups year after year despite studies which show that “prescriptions” for fruits and veggies could reduce health care costs by $40 billion annually. Or that 20,000 cancer cases could be prevented each year.

California Ag Today2019-09-23T15:06:22-07:00September 23rd, 2019|

Even Organic Production of Strawberries Not Sustainable

Data Shows Even Organic Production Uses Resources

By Jessica Theisman, Associate Editor

Is growing strawberries organically sustainable? That’s something that Surendra Dara is trying to find out. Dara is a UC Cooperative Extension Advisor in Entomology and Biologicals. He is based in San Luis Obispo County as well as Santa Barbara County. Dara met with California Ag Today recently and let us in on his research and some of his findings.

“I have not come across a mainstream grower that has told me that organic is sustainable,” Dara said.

After pulling in data and understanding the inputs, Dara is asking if there is anybody out there that has a different opinion.

“When we are talking about sustainability, we are looking only in terms of non-chemical being the sustainable, ecological practice,” he said.

There are such things as organic pesticides that harm natural enemies.

“Some of the organic ones can be as bad as some of the chemicals,” Dara said.

Data is showing that growing strawberries organically has not been sustainable economically. In terms of the carbon footprint and the bigger picture, “even organic production is not sustainable with the resources because certainly some resources are being used up,” Dara said.

California Ag Today2021-05-12T11:05:02-07:00July 10th, 2019|

2019 Strawberry Harvest is Brisk

Labor Tight, But Incentive Programs Keep Berries Harvested

By Patrick Cavanaugh, Editor

The 2019 strawberry harvest is going strong, and field employees are busy picking at the height the ripeness. Carolyn O’Donnell, a communication director for the California Strawberry Commission based in Watsonville, said lots of hands are harvesting the berries.

Carolyn O’Donnell, communications director, California Strawberry Commission

“We need to harvest the berries when ready,” O’Donnell said. “We can’t leave the ripe berries on the plant a few extra days, and we can’t harvest them early and then ripen them in some other modified atmosphere. They have to be picked when they’re ready to go. So, timing is part of it, as well as just having an adequate supply.”

O’Donnell explained how growers are handling the tight labor supply.

“It’s been a challenge. The growers have been doing all kinds of different incentive programs. Definitely, wages have been raised, different benefits have been offered, but we do find that growers are still struggling to keep up with their harvest,” O’Donnell said.

And when those harvesters out there picking the strawberries, they want to make the money, and they are in fact running back and forth with their trays to refill them.

“We are definitely in a busy harvest season right now. And so with a quick harvest comes incentive pay. And harvest workers will be hustling a little bit more. There are lots of berries to pick. There is money to be made,” O’Donnell said.

California Ag Today2019-07-08T16:37:07-07:00July 8th, 2019|

Bio-Control for Strawberry Growers

Strawberry Growers Lean on Biologicals to Manage Pest

By Jessica Theisman, Associate Editor

California Ag Today recently met with Surendra Dara, a UC Cooperative Extension entomologist based in San Luis Obispo County. According to Dara, California strawberry growers follow many sustainable options.

“Growers are well-educated and have a support system that provides information to them very regularly,” Dara said.

Growers try to apply as much of the IPMs as possible, but there is always a lot more scope in terms of using non-chemical alternatives. That is an area that has room to grow.

“The more we know about the options and their potential, they can be more adopted,” Dara said.

He explained that the strawberry growers often lean on biological insects such as beneficial mites that treat those damaging insects. It’s all part of IPM.

The insects are used outdoors along with in greenhouses.

“A bio-control is very well done in strawberries for mite control, but we do not have similar natural enemies for other pests,” Dara said.

There are botanical and microbial options for pest and disease management, and a lot of work is being done about understanding how they work and placing them in the right strategy.

“So, there is definitely plenty of options for us,” Dara said.

California Ag Today2021-05-12T11:01:47-07:00June 28th, 2019|

Electric Tractors Will Soon Be Available

With So Many Electric Cars, Why Not Electric Tractors?

By Patrick Cavanaugh, Editor

There are many different models of electric cars—they are even mainstream in most U.S. cities and other countries—and now farmers may soon have electric tractors to use in specialty crops in California.

Bakur Kvezereli is president and CEO of Ztractor, the first autonomous electric tractor for specialty crops. Kvezereli, who is based in Palo Alto, explained why the tractor is being developed in California.

“First, California is our market. Second, we teamed up with some great engineers, who graduated from Stanford, and my school, which was MIT. We were friends, and we wanted to look into this technology looking to replace the 25 or 30 HP diesel motor as well as the 30-gallon diesel,” he said.

“And we started as an electric tractor company in September 2017. And in two months, we realized that to achieve an electric tractor, you have to find a solution for making it autonomous,” Kvezereli explained.

“We now have three models in our manufacturing pipeline. One 24 horsepower will be available to the farmers this year. The next model will be a bigger tractor, 45 horsepower, which will be available 2020, and a 125 horsepower will be available in 2021.”

“Our basic tractor will have all the usual features found in most other tractors. The premium model line will have more features, especially on the software and hardware area. The zTractors will have no emissions and no hydraulics—just strong torque power.”

A four-hour charge will provide 6 to 10 hours of work in the field. “It requires only level two charging similar to car charging. “We are exploring a better battery, however currently it is the nickel ion technology,” Kvezereli said

“Horsepower is where we estimate the metrics for a tractor. What we think farmers care about is torque. In electric, to achieve higher torque is much easier than to achieve it with diesel power, and electric technology in general is very reliable for many types of tasks,” said Kvezereli.

The electric tractors keep the same three-point hitch as well as a PTO, both electrically operated.

“We build everything based on the requirements for the PTO and three-point hitch, and I think that’s what makes the Ztractor different from any other robotics companies that will provide a better tractor. It’s a general purpose and can replace a regular traditional tractor,” he said.

The main farming operations will be strawberry vineyards and vegetable operations. The tasks will include soil preparation and crop management. Harvest tasks are not yet available.

The prices for the tractors, calculated at $1,000 per horsepower, are similar to traditional tractors.

California Ag Today2019-06-05T15:01:14-07:00June 5th, 2019|