California Ag Network

Category: Vegetable Industry

  • Researchers & Grower-Shipper Association Collaborate to Battle INSV

    Grower-Shipper Association of Central California (GSA) — Implementing effective disease and pest management strategies is a continual challenge for farmers. While these challenges are not new in agriculture, they impact more than just farmers. Lower yields due to disease and pest pressure affects farm employees and harvesting crews too and can also inhibit our ability to provide a steady supply of affordable and healthy produce to consumers.

    Unfortunately, farmers of leafy greens are now dealing with the re-emergence of a damaging disease called thrips-vectored Impatiens Necrotic Spot Virus or INSV. According to local farm advisors this increase in INSV is often accompanied by Pythium wilt infections, which is a relatively new problem in the region.

    Lettuce fields are infected by INSV via thrips migrating in from infected host plants in the early spring. Fields infected by INSV cause stunting, yellowing, wilting of the outer leaves and eventual death for leafy greens. Currently, there are no effective treatments for INSV and Pythium wilt on organic and conventional lettuce farms.

    To support farmers as they battle INSV, GSA created a new task force to identify major research questions, examine treatment strategies, develop treatment efficacy trials and build a grower education program specific to these diseases.

    Mary Zischke, former Executive Director of the California Leafy Greens Research Board, was hired by GSA to lead and coordinate Task Force activities. In addition, to assist local farm advisors and help advance University of California cooperative research efforts, GSA added Jasmine Rodriguez to its team. Rodriguez is currently working toward her biology degree at California State University, Monterey Bay and also serves as a laboratory assistant for entomology research projects at the UC Cooperative Extension in Monterey County.

    “Mary and Jasmine will provide our industry with the additional personnel resources and experience as we combat this complex disease and pest control problem,” says Christopher Valadez, GSA president.

    To further expand resources and personnel, GSA has applied for a California Department of Food and Agriculture Specialty Block Grant. The grant would allow scientists to conduct multi-year field research trials assessing the effects of common crop rotation sequences, monitor Pythium wilt and INSV occurrence in commercial fields, conduct greenhouse studies to characterize the interactions between Pythium wilt and INSV in lettuce to understand their impacts on overall plant health and disease management.

    If awarded the grant, the GSA team will work with researchers from California State University, Monterey Bay and U.S. Department of Ag, Agricultural Research Service in Salinas. Grant outcomes would include knowledge of the impact of crop rotation on Pythium wilt and thrips populations as well as the interplay between Pythium wilt and INSV and how to jointly manage them.

    While GSA is hopeful the grant provides future resources, we will continue moving needed work forward to uncover potential answers and treatment strategies so farmers in our region can minimize losses. Farming equates to surmounting challenges and GSA is committed to supporting farmers as they face those challenges.

  • New Food Freezing Concept Improves Quality, Increases Safety and Cuts Energy Use

    Shifting to a new food freezing method could make for safer and better quality frozen foods while saving energy and reducing carbon emissions, according to a new study by U.S. Department of Agriculture’s Agricultural Research Service (ARS) and University of California-Berkeley scientists.

    “A complete change over to this new method of food freezing worldwide could cut energy use by as much as 6.5 billion kilowatt-hours each year while reducing the carbon emissions that go along with generating that power by 4.6 billion kg, the equivalent of removing roughly one million cars from roads,” said ARS research food technologist Cristina Bilbao-Sainz. She is with the Healthy Processed Foods Research Unit, part of ARS’s Western Regional Research Center (WRRC) in Albany.

    “T­hese savings could be achieved without requiring any significant changes in current frozen food manufacturing equipment and infrastructure, if food manufacturers adopt this concept,” Bilbao-Sainz added.

    ARS scientists Cristina Bilbao-Sainz (right) and Roberto Avena-Bustillos demonstrate the use of isochoric freezing chambers. Photo: U.S. Department of Agriculture.

    The new freezing method, called isochoric freezing, works by storing foods in a sealed, rigid container—typically made of hard plastic or metal—completely filled with a liquid such as water. Unlike conventional freezing in which the food is exposed to the air and freezes solid at temperatures below 32 degrees F, isochoric freezing preserves food without turning it to solid ice.

    As long as the food stays immersed in the liquid portion, it is protected from ice crystallization, which is the main threat to food quality.

    “Energy savings come from not having to freeze foods completely solid, which uses a huge amount of energy, plus there is no need to resort to energy-intensive cold storage protocols such as quick freezing to avoid ice crystal formation,” Bilbao-Sainz said.

    Isochoric freezing also allows for higher quality storage of fresh foods such as tomatoes, sweet cherries and potatoes that are otherwise difficult to preserve with conventional freezing.

    Another benefit of isochoric freezing is that it also kills microbial contaminants during processing.

    “The entire food production chain could use isochoric freezing—everyone from growers to food processors, product producers to wholesalers, to retailers. The process will even work in a person’s freezer at home after they purchase a product—all without requiring any major investments in new equipment,” said WRRC center director Tara McHugh, co-leader of this study. “With all of the many potential benefits, if this innovative concept catches on, it could be the next revolution in freezing foods.”

    UC-Berkeley biomedical engineer Boris Rubinsky, co-leader of this project, first developed the isochoric freezing method to cryopreserve tissues and organs for transplants.

    Since then, ARS and UC-Berkeley have applied for a joint patent for applying isochoric freezing to preserving food. The research team is now developing the best applications for this technology in the frozen foods industry, especially scaling up the technology to an industrial level. They also are seeking commercial partners to help transfer the technology to the commercial sector.

    UC-Berkeley mechanical engineer Matthew Powell-Palm, one of the lead authors of the study paper, noted that “isochoric freezing is a cross-cutting technology with promising applications in not only the food industry, but in medicine, biology, even space travel.”

    WRRC has also been designated a National Historic Chemical Landmark in 2002 by the American Chemical Society for developing the Time-Temperature Tolerance studies, which made possible the production of stable, safe and high quality frozen food, revolutionizing the industry in the 1950s.

    This research was published in Renewable & Sustainable Energy Reviews.

    The Agricultural Research Service is the U.S. Department of Agriculture’s chief scientific in-house research agency. Daily, ARS focuses on solutions to agricultural problems affecting America. Each dollar invested in agricultural research results in $17 of economic impact.

  • California Processing Tomato Crop Forecast Below May’s Expectation

    Contracted production for California processing tomatoes is forecast at 11.1 million tons, averaging 48.9 tons per acre. The current production forecast is 1.9% below last year’s contracted production, and 4.3% below the May forecast. The projected harvested acreage of tomatoes grown under contract is 227,000 acres, which 0.4% lower than in 2020.

    Drought concerns impacted planting decisions for the 2021 processing tomato crop and acreage has decreased significantly from early season intentions. Extreme high temperatures in May and throughout the summer lowered expected yields and slowed down operations at the canneries. Crop quality is reported to be average or slightly above average.

    Harvest began the first week of July and the flow of tomatoes has generally kept pace with the previous two years. The Processing Tomato Advisory Board published shipments through August 28, 2021, showing a 4.3% decrease compared to the end of August in 2020.

    This processing tomato estimate is funded by the California League of Food Producers.

  • The Threat of Branched Broomrape for California Processing Tomato

    Branched broomrape (Phelipanche ramosa), a parasitic weed that was the focus of a $1.5 million eradication effort four decades ago in California, has recently re-emerged in tomato fields in several Central Valley counties. Processing tomatoes are important to the California agricultural economy; the state produced over 90% of the 12 million tons of tomatoes grown in the United States in 2018. Branched broomrape is listed as an “A” noxious weed by the California Department of Food and Agriculture (CDFA); discovery of broomrape in California tomato fields leads to quarantine and crop destruction without harvest, resulting in significant economic loss to growers.

    In countries where broomrape is common, yield reductions caused by this parasitic weed can range from moderate to 80%, depending upon the infestation level, host and environmental conditions. Developing a detailed understanding of the biology of this weed under local conditions is an important step towards developing effective management plans for California. In the latest issue of California Agriculture (a University of California, Agriculture & Natural Resources publication), extension researchers discuss branched broomrape in the context of California production systems, particularly of tomato. They also discuss the potential management practices that could help to prevent or reduce the impacts of branched broomrape in tomatoes and other host crops. Read the full article HERE.

  • Field Bindweed Yield Impacts on Processing Tomatoes May be Less than Expected

    Figure 1. Field bindweed (Convolvulsus arvensis)

    Field bindweed (Convolvulsus arvensis) is considered by many tomato growers to be the most problematic of all weeds in California production areas. Indeed, field bindweed and the closely related morning glory weeds were ranked the 8th most troublesome weeds in North America in a recent survey by the Weed Science Society of America. The rapid adoption of drip irrigation and the economic necessity of maintaining the beds and replanting with only minimal tillage for multiple seasons in processing tomatoes has created a system where field bindweed has become more prevalent. Field bindweed is extremely difficult to control because it propagates from seed and vegetatively from buds formed in the roots. Seedlings can be controlled with tillage when very young, but they become perennial very rapidly. Chemical control of seedlings is possible, but established plants are much more difficult to control. Established plants often have a large root system relative to the amount of top growth, and thus are extremely tolerant of post emergence herbicides such as carfentrazone (Shark), glufosinate (Rely), and glyphosate (Roundup).

    Bindweed is a headache not only for its persistent and pernicious growth habit and ability to reduce tomato yields, but also because it can physically stop a processing tomato harvester in the field. Vigorously growing vines can become entangled around the shaker and conveyor belts, requiring the equipment operator to shut down and manually clear out the foliage.

    Several years ago, myself and other UC researchers conducted herbicide trials evaluating field bindweed control — with marginal success. In a given year and location, most of the registered herbicides in tomatoes gave only temporary suppression – about 40 – 80% bindweed control at 8 weeks after transplanting. Best results were observed where herbicides were stacked: trifluralin (Treflan) pre-plant incorporated followed by rimsulfuron (Matrix) post. Glyphosate helped in situations where the bindweed emerged early and could be applied before transplanting (Figure 2).

    Figure 2. Bindweed control plots at UC Davis. Untreated control on the left, glyphosate, trifluralin, and rimsulfuron on the right.

    Earlier this year, I was asked to summarize the effects of weeds on processing tomato yield. This made me go back and look at this work, but with a slightly different emphasis: impact of weed control (or really, lack of weed control) on yield. To increase the size of my dataset, I also included data from trials done at UC Davis. Where I had data for both yield and weed control in good, replicated trials, I performed a regression analysis comparing % weed control and % relative yield (relative yields remove the year-to-year and location variability). In the end, I used 4 trials from 2012-13 (Table 1).

    Scott Stoddard, UC Cooperative Extension Merced-Madera Counties Vegetable Crops and Soils Farm Advisor

    Surprisingly, these data suggested that where bindweed dominated, it did not have a big impact on processing tomato yield. Even with just 50% control 8 weeks after transplanting, potential yield was 88-95%. This may have occurred because bindweed does not shade out the tomato canopy nearly as much as some of the common annual weeds. However, when tall broadleaf weeds dominated, such as pigweed, nightshades, and lambsquarters, yields dropped rapidly. I had some plots with a 99% yield drop if these weeds were allowed to grow all season. In this situation, the weeds towered over the tomato canopy.

    There have been no new registered herbicides in processing tomatoes in the last 10 years, while robotic weed control has progressed rapidly during this time. Unfortunately, neither our current slate of registered herbicides nor robots provide adequate control of field bindweed. This may not matter as much as previously thought, however. The annual grasses and broadleaf weeds have far greater yield impact, especially when they grow tall and shade out the crop. Thankfully, there are several registered herbicides that provide effective control of those weed types. — By Scott Stoddard, UC Cooperative Extension

  • Western Growers Unveils Middle School to Post-Graduate Agtech Career Development Pipeline

    Western Growers (WG) has bolstered its workforce development efforts with the launch of five initiatives aimed at transitioning the agriculture workforce to master rapidly developing agricultural technology. The initiatives make up WG’s Agtech Workforce Readiness Campaign, which was announced last night at AgTechX Ed at Reedley College.

    “We need agtech startups and technology experts to help us automate key functions such as harvesting, weeding and thinning,” said Western Growers President and CEO Dave Puglia. “As their innovations come forward, we will need trained and creative people to work on our farms and in our facilities who are adept in everything from agriculture and agronomy to data analytics and technology integration. These initiatives are designed to make sure we get there on time.”

    WG started its agtech workforce development focus in 2016 with the launch of Careers in Ag – a career pathways program. However, with the rapid development of innovative agtech solutions in the past few years, WG has ramped up its efforts to meet the growing demand for workers with a different type of skill set.

    The WG Agtech Workforce Readiness Campaign include the following initiatives:

    • AgTechX Ed: A statewide initiative aimed at developing a future workforce with the skills and knowledge to navigate emerging on-farm technology.
    • NextGen Curriculum Development: A project that will address the need for agriculture worker education by developing a curriculum that can be leveraged across campuses in the University of California, California State University and California Community College systems to provide the training needed for agtech expertise for the next-gen agricultural workforce.
    • Junior AgSharks: Students from middle and high schools in rural areas are invited to serve as AgSharks, where they listen to pitches from agtech startups and vet their technologies as well as learn about the latest technologies by interacting with leaders in the agriculture industry and venture capitalist space.
    • Home for the Holidays: An annual professional mixer where college students are invited to an exclusive meet-and-greet with agriculture industry leaders and technology companies.
    • Careers in Ag: A career pathways program encourages college students to pursue science, technology, engineering and mathematics (STEM) careers within the agricultural industry.

      “The Careers in Ag Program reinforced my desire to work in the ag industry,” said Anahi Huerta, one of 250 students who have participated in the Careers in Ag Program. “During the program, I was exposed to the variety of careers available in ag. When I graduated UC Davis, I was offered a position at a farm in California’s Coachella Valley and have been able to apply my managerial economics degree to my current role as food safety coordinator.”

      To accompany the initiatives, WG also rolled out the Agtech Workforce Readiness Campaign website today: www.agtechworkforce.com.

      The website is a one-stop-shop where stakeholders can find information about WG’s initiatives; watch videos and read articles about students who are already making a difference in the workforce; hear directly from farmers about workforce needs; and join the cause.

  • Measuring Nitrogen in Green Manures (Cover Crops)

    A crimson clover plant, which is generally recommended to grow in a mixture of grasses, which was used in this study (photo by Sandra Wayman)

    Both chemical fertilizers and cover crops can help build the nitrogen content in soil. But cover crops come with many other benefits, like improving soil structure and boosting beneficial microbes. Researchers at Cornell University are looking at ways to help breed better cover crops, also known as green manures, that could help farmers in their quest to grow crops in the most sustainable way. Their results were published in Crop Science, a publication of the Crop Science Society of America.

    Katherine Muller and her team are working on strategies to measure nitrogen fixation in breeding programs for two common cover crops: crimson clover and hairy vetch. Both crops can pull nitrogen from the air to help them grow. This is called nitrogen fixation.

    “Green manures are crops used to improve soil fertility,” says Muller. “They help the soil by adding nutrients. We look at legumes, which bring nitrogen into the soil due to their symbiotic relationship with bacteria.”

    The use of legume green manures has been around for thousands of years. However, after the 1950s, chemical fertilizers became the main nitrogen source for farmers in developed countries. This is because two scientists, Haber and Bosch, found a way to pull nitrogen from the air, and make chemical fertilizer.

    Though this type of fertilizer is productive, it also takes energy to make it – and it can easily slip into water bodies if not managed correctly.

    “Cover crops are important ecological management tools,” says Muller. “They foster microbial communities and put nutrients in the soil. Essentially, they help build fertile soil that can supply nutrients when plants need them.”

    The use of cover crops can be risky to farmers because they cannot determine the exact amount of nitrogen supplied to the soil. Chemical fertilizers allow for the exact calculation of the amount of nitrogen applied to a crop. But how much nitrogen is provided by each type of cover crop isn’t a known number.

    The amount of nitrogen supplied by a legume cover crop depends on how well it grows and how much of its nitrogen comes from fixation versus uptake from soil. Currently, cover crop seeds available do not have selective breeding for nitrogen fixation – a valuable trait.

    Plant breeders are working to develop cover crop varieties that reduce the risks and increase benefits to farmers. They hope that better varieties will increase the use of cover crops as an alternative to chemical fertilizer. Nitrogen fixation is one of their top priorities for legume green manures.

    “We aim to help plant breeders develop strategies to target nitrogen fixation in cover crops,” explains Muller. “Because nitrogen fixation is a complicated trait that changes as plants grow, the timing of measurements is important.”

    A root system of a hairy vetch plant, with nodules that contain a symbiotic nitrogen fixing bacteria (Photo by Katherine Muller).

    For farmers, the most important measurement of nitrogen fixation is when the crop is terminated. Legume green manures are usually terminated in the late flowering stage. Earlier termination means the crop is likely to resprout and become a weed. However, breeding programs for hairy vetch and crimson clover cannot take that measurement, as they need to remove the plant before cross-pollination.

    “Our team did a field experiment with an active breeding program,” says Muller. “We collected plant tissues and measured nitrogen fixation. We were able to tell how much of the plant’s nitrogen comes from fixation versus the soil.”

    The team tested three kinds of samples that a plant breeder may take to compare them to the sample most relevant to farmers. They then measured nitrogen fixation by sending their samples to a lab that measures total nitrogen content and the abundance of a naturally occurring stable isotope.

    Nitrogen from soil usually has a higher abundance of the nitrogen stable isotope than nitrogen from fixation. This allows researchers to estimate the proportion of nitrogen a plant obtains from soil versus fixation.

    “Our recommendation is to collect stems from each plant in the early flowering stage to measure the nitrogen fixation via stable isotopes,” says Muller. “This provides a good proxy for nitrogen fixation in whole plants, measured in the late flowering stage that is more relevant to farmers.”

    According to Muller, if breeders are going to add one measurement, it should be this. The proportion of nitrogen obtained by fixation often does not correlate with plant size or other measurements.

    “It is important to measure actual nitrogen fixed in the cover crop because it can vary,” says Muller. “Farmers want to know how much nitrogen they are bringing into their fields. We need to accurately measure and provide this information to help farmers make decisions. We hope our research will encourage more farmers to adopt legumes cover crops as a nitrogen source.”

    Katherine Muller is a postdoctoral researcher at Cornell University. This research was done in conjunction with the Legume Cover Crop Breeding Project, funded by the United States Department of Agriculture.

    American Society of Agronomy, Soil Science Society of America, Crop Science Society of America: Collectively, these Societies represent more than 12,000 individual members around the world. Members are researchers and professionals in the areas of growing our world’s food supply while protecting our environment. Together we work toward solutions to advance scientific knowledge in the areas of agronomy, crop science, and soil science.

  • Soil-Biodegradable Mulch In Strawberry Field Day, Aug 17

    The UC Cooperative Extension, Washington State University and Monterey Bay Marine Sanctuary have been working together this past year field testing five different formulations of biodegradable bed mulch in strawberry.  See five types of soil-biodegradable mulches (BDMs) applied to strawberries in Salinas Valley. Learn what a BDM is, what it is made from, and comparative economics with traditional PE plastic mulch. See first-hand how it is performing in the field and learn from other farmers who are trialing it about their experiences and expectations. Learn about how plastic impacts soil health. For more information on the event, contact Jazmine Mejia-Muñoz at jazmine@californiamsf.org or call (661) 331-2612. Register HERE  All local and state health guidelines will be enforced. If you have not received a Covid vaccine please wear a mask.

    Location:

    Strobel Ranch
    1656 Castroville Road
    Salinas, CA 93907
    This event is supported by the ‘California Climate Investments’ program.

  • New Ag One President Brings over 30 years’ Experience to Fresno State

    Jim Razor had little inkling how much the key agronomic principles he learned 30 years ago in his Fresno State classes on weeds and vegetable crops would serve him every day.

    After he graduated with a plant science degree in 1990, he began a career as a pest control adviser and is now vice president for J.G. Boswell Company, an internationally-respected agricultural company.

    The newly-appointed Ag One Foundation president currently oversees processing facilities for two of Boswell’s premier products, tomatoes and pima cotton, as well as an edible oil mill, planting seed cleaning and packaging facility. He also manages areas that involve logistics, safety, risk management, workers compensation and environmental affairs.

    “I was fortunate to have wonderful instructors like Dr. (Mahlon) Hile, Dr. (Gary) Ritenour and Dean (Dennis) Nef,” Razor said. “They gave me an incredible mix of agricultural perspectives that range from the fields to economics. My job today is always changing, and the innovation, organization and ability to meet deadlines that I learned from my classes have served as a great foundation.”

    Born on a small farm near Exeter, Razor’s background mirrors many current students. He transferred from the College of the Sequoias to Fresno State as a junior and worked hard to graduate in three semesters. He took 23 units his final semester so he could find a job and support his young family.

    “We had to take out loans to support my education, and I had some scholarships, too,” Razor said. “Ag One’s role is so important to students, through its commitment to supporting scholarships and a wide network of industry ties and partnerships.”

    Razor and his company are also connected to the Jordan College of Agricultural Sciences and Technology at Fresno State through an endowed chair position in the Plant Science Department. Dr. Sharon Benes currently holds the position.

    Additionally, the J. G. Boswell Foundation established a permanent fund in memory of longtime company farm manager Dave Cosyns to support the University Agricultural Laboratory. Cosyns graduated from Fresno State in 1971 and was an accomplished farmer and industry member.

    The Boswell company and foundation, a founding member of the Pinnacle Society for campus philanthropists and supporters, has contributed more than $2 million to Fresno State.

    “It’s great to have so many special bonds with Fresno State,” Razor said. “Getting to meet with the faculty and students confirms that the college still has the same mission today. Nearly half of our agronomy team are Fresno State graduates, including two district managers, and I know they are well prepared for anything.”

    Ag One, which was founded in 1979, has raised nearly $26.7 million in endowed funds. In that span, about 4,800 students have been awarded over $7.6 million in scholarships and another $950,000 is projected in 2021-22.

    Razor’s first Ag One event in his new role is the annual Ag Boosters BBQ fundraiser, tentatively slated for Sunday, Sept. 12, at the Panoche Creek River Ranch.

    As president, Razor succeeds Annie Stuhr, who completed her one-year term on June 30. Other current Ag One Foundation board officers include:

    • Stanley Kjar, Jr., vice president (Fresno, Pearson Realty)
    • Roger Isom, treasurer (Fresno, California Cotton Ginners/Western Agricultural Processors Association)
    • Nick Biscay, secretary (Madera, Stanislaus Farm Supply)

    New members on the 23-person board of directors include:

    • Jason Baldwin (Kerman, Panoche Creek Packing)
    • Fendley Ragland (Fresno, PGIM Real Estate Agricultural Investments)

    For more information on the Ag One Foundation, its programs and upcoming events, contact 559.278.4266 or agone@csufresno.edu.

  • With Over 40,000 Vaccinations Administered, Efforts To Protect Farm Employees Continue

    With over 40,000 vaccinations administered to farm workers through the combined efforts of the Grower Shipper Association of Central California (GSA) and Clinica de Salud del Valle de Salinas (CSVS), this partnership has added smaller clinics for essential workers and will also provide vaccines to children and families of farm workers at farms and facilities.

    “Over the last five months, mass clinics effectively and efficiently provided thousands of farm workers with needed vaccinations,” says Christopher Valadez, GSA President. “But as we have reached this significant vaccination level, our efforts have evolved to smaller clinics which will vaccinate hundreds of farm workers at a time. These clinics will continue to be conducted in coordination with ag employers,” Valadez says.

    Recognizing the need to also protect the health of the families of farm workers, GSA and CSVS recently held vaccination clinics for children. The first clinics were conducted at CSVS in King City and Sierra Farms in Moss Landing.

    “We want to provide these clinics prior to schools re-opening in the fall so children over 12 can be vaccinated in a trusted place and at a time and location that is most convenient for parents,” Valadez says.

    GSA and CSVS conducted their first mass vaccination clinic on February 26. The mass vaccination clinics held at the Rodeo Grounds in Salinas and the Salinas Valley Fairgrounds in King City continue through July and have vaccinated several hundred to thousands of ag employees per clinic. These clinics received national attention for the volume of vaccinations administered and protection provided as essential workers returned for the harvest.

    “While we have made great progress in protecting farm workers from COVID-19, this is a persistent and evolving virus as evidenced by what we are seeing with the Delta variant,” Valadez says. “We must be diligent about onsite worker protection strategies, providing safe and comfortable quarantined housing options for those exposed or infected as well as giving essential employees easily accessible vaccines. The hard work must continue to ensure the health and safety of our region’s farm workers,” he adds.  — By Christopher Valadiez, Grower-Shipper Association President