Maeli Melotto and her team at the UC Davis Department of Plant Sciences are looking for strains of lettuce that are genetically stronger at resisting bacteria that can make people sick. Their work has led to the identification of a gene that could play a role in the plant’s susceptibility to E. coli, a bacterium that causes potentially lethal intestinal illness.
If the team could develop lettuce that can fight off the bacterium, that would avoid thousands of cases of sickness each year, cut production costs for farmers and save millions of dollars in public health expenses.
Lettuce “sweats” substances onto the surface of leaves that E. coli and other bacteria can eat. In addition, bacteria can live just below the surface of lettuce leaves. Melotto, a professor specializing in the interactions between plants and microbes, is studying the genetic factors that determine how long bacteria can endure in the leaves. She and her team looked at more than 300 samples of lettuce and how they react to the pathogens, identifying the gene responsible for letting them in.
Their next step is to test whether removing that gene could make lettuce more resistant to bacteria.
Maeli Melotto, a professor in the UC Davis Department of Plant Sciences, and her team have found a gene she thinks governs whether lettuce can resist bacteria such as E. coli. (Trina Kleist/UC Davis)
Some lettuce more likely to “feed” bacteria
In a related study, Melotto’s team is looking at the surface of lettuce leaves and the layer just below the surface, which has tiny spaces where bacteria can live. The researchers want to learn what natural chemicals are in these two areas, and what compounds lettuce releases onto the surface of leaves that bacteria can use as food. Melotto expects to find that some types of lettuce are genetically disposed toward “feeding” bacteria.
Melotto presented her findings at meetings earlier this year of the California Specialty Crops Council and the California Leafy Greens Research Board. Her work is funded in part by a five-year grant from the National Institute of Food and Agriculture.
Strawberry growers, researchers, and other industry members from around the globe are invited to attend the 10th North American Strawberry Symposium (NASS), a meeting of to be held in conjunction with the annual North American Strawberry Growers Association (NASGA) conference, March 7-10, 2023 at the Embassy Suites in San Luis Obispo, California, USA. California, where nearly 90% of U.S. strawberries are grown, features a unique coastal environment with its western ocean exposure, moderate temperatures, warm sunny days, and cool foggy nights –perfect for growing strawberries year-round.
The Symposium will include two and a half days of workshops, reception, research presentations, marketing presentations, poster sessions and an award luncheon, and will be followed by a post- conference tour on March 10, which will encompass strawberry production in the region as well as the research, training and testing facilities at the CalPoly Strawberry Center. The Program Committee is committed to making this a world-class research symposium for growers and scientists, and we eagerly look forward to seeing you in San Luis Obispo.
Subject areas for oral and poster presentations include: Global and North American Overviews, Breeding, Genetics, Molecular Biology, Disease & Pest Management, Propagation & Nursery Management, Cultural Practices, Indoor Production, Precision Agriculture, Robotics, Automation, Plant Nutrition and Water Management, Plant Physiology, Economics of Production Practices, Post-Harvest Quality Management, and Food Safety.
Workshop topics include: Disease Management, Nursery Developments, Entomology, Strawberry Breeding Tools and Tips, Production Management/Plant Physiology, Getting Started with Automation/Precision Agriculture, Indoor Production, Methyl Bromide Alternatives, Novel Weed Management Approaches. View the full program HERE.
Look for a mail-in registration form and more program details (abstract deadlines, keynote speakers, etc.) and opportunities for industry, organization and agency sponsorship on the NASGA website: http://www.nasga.org/. Please spread the word to fellow researchers and strawberry growers.
The Central Coast Olive Oil Competition, hosted annually by the California Mid-State Fair and in partnership with the Lodi Grape Festival, is now accepting entries. The 15th Annual competition will take place in April 2023 and feature olive oil from across the state of California.
Olive oils are separated into two categories: extra virgin and flavored. The categories are then separated into classes by varietal which have been reorganized for 2023. The panel of competition judges, who are from across the state of California, evaluate each entry according to aroma, taste, and intensity, ranging from delicate to robust. Judges are qualified based on their experience using olive oil in cooking, education and production. The awarded organic oils (if applicable) will be noted as being organically produced.
The early bird registration period is now through Friday, March 24 and is $65 per entry. From Saturday, March 25 to Sunday, April 2, registration increases to $75 per entry. Register today at https://cmsfw.fairwire.com/
The UC Cooperative Extension will be hosting its 2023 Carrot Research Symposium on Tuesday, February 14th online via Zoom from 8 a.m. to noon. Attendance is free and open to the public. The symposium will focus on the latest information in research and activities related to carrots, with 1.5 hrs. of ‘Other’ CEUs applied for from the CA Dept. of Pesticide Regulations. Some of the highlighted topics on the agenda include: screening carrot lines for resistance to cavity spot and other traits, carrot breeding to develop/introduce improved cultivars for CA production, root-knot nematode injury prevention in CA fresh carrot production, steam disinfestation of weed seed banks in carrots, and more. See the full agenda HERE. Register to attend HERE.
Like all living organisms, vegetables need nutrients for their proper growth and development. But where do they get their mineral nutrients from? The answer is soil. Okay, the next question is, how do nutrients go from the soil and into the vegetables?
The three processes responsible for nutrients from the soil reach the plant are diffusion, mass transport, and root interception. I know it seems to be complex to understand, but I promise it is not.
Diffusion
When the concentration of nutrients is higher in the soil than in the plant root, then the nutrients in the soil will move from a region of higher concentration (soil) to a region of lower concentration (vegetable). Potassium and phosphorus are examples of nutrients that get into the vegetables by diffusion.
Mass transport
Nutrients move to the roots via water. As plants transpire water, it draws water and nutrients from the soil up through the root system. Mass transport accounts for nutrient acquisition of mobile nutrients, such as nitrogen and sulfur.
A radish plant with soil pulled aside to demonstrate the root system. Plants get their nutrients from the soil – and if the soil is deficient in nutrients, the resulting crop will be too. Credit: Carlos Bonini Pires
Root interception
Vegetable roots grow through the soil to meet nutrients. As the root grows through the soil it generally only comes in contact with about 1% of soil volume. Good soil structure is essential in the process of root interception. Soil compaction can significantly limit root growth and interception with nutrients throughout the soil. Some important macro and micronutrients such as calcium, magnesium, iron, manganese, and zinc are absorbed by root interception.
Of course, some nutrients are absorbed in more than one way. For example, iron and zinc can be absorbed by three different methods. As you can see, there are a lot of variables that may impact how vegetable acquire their nutrients.
Moving within the plant
Once the nutrients get inside the plant, they can move upward to the leaves and developing vegetables. How? Like a human body, plants also have a vascular system. Rather than a bloodstream, they have xylem and phloem. The Xylem distributes water and dissolves nutrients upward to the plant, from the roots to the leaves. The phloem carries nutrients downward, from the leaves to the roots (photosynthesis). In simple words, the root is the mouth and xylem and phloem are the veins of a “plant body.”
Checking soil nutrients
Soils nutrient concentration is crucial for ensuring high nutrient content vegetables. If the soil has few nutrients, no matter how the plant tries, it will not be able to acquire the nutrients it needs for good yields and plant health.
That is why soil testing is important, and correct fertilization might be needed. Understanding how nutrients are absorbed is vital for a placement strategy. Phosphorus and potassium are nutrients with low mobility and are absorbed by diffusion, so it is important to place them near the plant. On the other hand, nitrogen can be spread over the plants since it is mobile in the soil. This is true whether you are applying organic or mineral fertilizer.
In agronomy, we pay attention to the nutrient 4R’s: right source, right rate, right time, and right place. This refers to choosing the right type of nutrient or fertilizer, applying at the right amount, when the plant can use it the most, and in the right location. By applying these principles to your home garden, you can increase your yields and create more nutritious produce for your next meal! — By Carlos Bonini Pires, Kansas State University
An illustration of a soybean plant growing in nutrient-rich soil, producing nutrient-rich soybeans on the left. On the right, a soil that has fewer nutrients will result in soybeans with less nutrients. Credit: Jim Toomey
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.
Hidden beneath the delicate, red skin and juicy flesh of a tomato is a wealth of nutrients and genetic makeup. With recent research on the first genome of a species in the tomatillo tribe (part of the tomato family), we now have a better idea of how this vital plant family came to be.
Put simply, a genome is a complete set of DNA (genetic material) in a plant. The genome contains all the information needed for a plant to develop and grow. When scientists assemble genetic sequences to build an entire genome– a lot like completing a puzzle – this helps them predict things like how a plant will grow (straight or crooked) and what the fruit might look like (thin or thick skinned.) This information is important for understanding how different varieties come to be and is key for breeding better crops.
“The tomato family is simply the most fascinating family. It consists of plants that are major crops, invasive weeds, important medicines, beautiful bedding plants, and many wild species that are crop relatives,” says Stacey Smith, a professor at the University of Colorado-Boulder.
This research was published in The Plant Genome Journal, a publication of the Crop Science Society of America.
A closer look at the flower and fruit of an Iochroma cyaneum shrub grown in southern Ecuador. Like its relative, the tomatillo, this shrub’s fruit has an enlarged husk growing around it. Researchers recently were able to create a full genetic sequence for the plant, called the genome.
Smith led the work on the sequencing the genome of Iochroma cyaneum, a wild shrub in the tomatillo tribe of the tomato family. Iochroma displays striking blue flowers but isn’t widely grown. Scientists like Smith can learn how important plant families evolved by collecting many genomes from different sub-species.
“Unlike most plants in the family with sequenced genomes, it is not a crop species. It’s also the only member of its entire tribe with genome assembled to the level of chromosomes,” says Smith. These unique traits make the new genome even more valuable to understand how the broader family evolved.
After sequencing the Iochroma genome and assembling the sequences into chromosomes like a puzzle, Smith’s research team compared it to other members of the family. The broader tomato family has almost 3,000 species. Some of these species, like belladonna, are poisonous to humans. Forty species have been domesticated, which include potatoes, eggplants, and hot peppers, in addition to tomatoes. All of these plants belong to the family are also called “nightshades.” In the puzzle example, this means that they all have a similar set of puzzle pieces, up to a point. From there, their puzzle pieces are different.
The genome told researchers that Iochroma was part of the family known as the “berry clade.” This subgroup forms “berries” which are juicy fruits with many seeds, like tomatoes and hot peppers. But the scientists were surprised to find that the family relationships within this clade were far from clear. The genetic evidence was uncertain about which species were most closely related. Biologists call this kind of disagreement “discordance.”
“This kind of disagreement often arises when lineages reproduce quickly within different species,” says Smith. “That may be what happened tens of millions of years ago when fleshy-fruited berries from this family burst onto the scene. As a result of this discordance, we can’t make definitive statements about which species are more closely related.”
A wild Iochroma cynaeum growing in southern Ecuador. South America is home to many diverse members of the tomato family, which also includes potatoes and chili peppers. Researchers can learn how important plant families evolved by collecting genomes from different sub-species. This information can inform future breeding efforts.
Still, the new genome gives a new look into the evolution of the family. One clue is how the genes have moved around. As species evolve, genes can move from one chromosome to another. Plants adjust efficiently to these changes. But Iochroma offered up a surprise. Its genome shuffling didn’t closely resemble any other sequenced genome, meaning the shrub has had its own unique evolutionary path.
“With the addition of the lochroma genome, we are working towards understanding how genes have been shuffled around during the evolutionary history of the berry clade,” says Smith. “We have only scratched the surface in terms of understanding how this diversity evolved.”
While the new research won’t produce a tastier tomato or tangier tomatillo right away, Smith says the family already offers a lot of flavors to the bold gardener. And, perhaps, an appreciation for the diversity offered by evolution.
“I would encourage anyone who is curious about nightshades to get to know some of the lesser-known crops — try out golden berries, ground cherries, pepinos, wonderberries, or naranjillas!” says Smith. “There are even species that can be eaten as greens. Many of these will happily grow in northern climates and bring a lot more flavor than any tomato you can find on the grocery store shelf.”
Funding for this research was supported in part by NSF-DEB 1355518.
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.
As of January, California’s tomato processors reported they have, or will have, contracts for 12.4 million tons in 2023, which is an increase of 18% compared to 10.5 million contracted tons forecast in the August 2022 California Processing Tomato Report. Processors estimate that the contracted production for 2023 will come from 248,000 acres, generating an average yield of 50.0 tons per acre. The contracted planted acreage forecast is 8% higher than the 2022 acreage of 229,000 reported under contract in August.
The USDA-NASS Pacific Regional Office surveyed California’s tomato processors for their intended contract acreage and tonnage for the upcoming 2023 season. The data reported by processors was either tonnage with derived acreage, or acreage with derived tonnage.
This early processing tomato estimate is funded by the California League of Food Producers.
The North American Blueberry Council (NABC) released the full slate of its recently elected board of directors, including new president Pat Goin of Goin’s Blueberry Lane in Indiana, and other board officers. Starting in 2023, the board has been expanded from six to 15 members, several of which hail from California. Among the new Board members is Todd Sanders, Executive Director of the California Blueberry Commission. “I am excited to join the NABC Board of Directors and help with the continued promotion and market development of the blueberry industry. The California blueberry industry has grown exponentially over the last 10 years and I look forward to representing the California blueberry industry in their efforts on the National level.”
The NABC board is charged with addressing issues, opportunities and industry practices that drive success and profitability in the production and distribution of blueberries in North America and around the world. Over the past two years, the NABC’s board leadership has taken a bold approach to further develop and drive the organization’s mission, including the expansion of board representation and new categories of membership to encourage membership growth.
Prior to her tenure as NABC board president, Goin served as vice chair of the board and chair of the NABC’s Government Affairs Committee. She was also the chair of the U.S. Highbush Blueberry Council’s (USHBC) Good Practices Committee.
“NABC continues to be uniquely positioned to unite our industry efforts,” explained Goin. “I look forward to working with our newly expanded board to accomplish together what none of us could accomplish alone. This is an exciting evolution for our organization, and I’m proud to be a part of where we are going.”
In addition to Goin, the 2023 executive board includes:
• Teddy Koukoulis, Chair Elect, Fabulous Farms LLC • Ellie Norris, Secretary, Norris Farms LLC • Art Galletta, Treasurer, Atlantic Blueberry Co. • Ken Patterson, Past Chair, Island Grove LLC
Newly elected members of the board include:
• Tom Avinelis, AgriCare Inc. • Chelsea Consalo, Consalo Family Farms • David Jackson, Family Tree Farms • Brittany Lee, Florida Blue Farms • Jason Smith, Fraser Berry Farms • Cesar Ortiz Mendoza, Aba Value/Berries Paradise • Bo Slack, California Giant Berry Farms • Ryan Lockman, North Bay Produce • Derek Eisele, Scenic Fruit • Todd Sanders, California Blueberry Commission
The Hass Avocado Board is now accepting applications for its yearlong Board Leadership Development program. The program includes customized training to help participants prepare to serve on the boards of avocado industry organizations such as HAB and the California Avocado Commission, among others. The deadline to complete the application is January 31. There are currently 12 open seats.
The course includes:
A curriculum that covers topics ranging from finance and fiduciary duties to understanding the roles of nutrition research and marketing
Gaining real-world experience by attending actual board meetings
Participating in on-campus instruction at the University of California Davis.
A potential trip to Washington, D.C. to meet with the U.S. Department of Agriculture
For those interested in leadership opportunities and serving on industry boards, this course provides valuable educational and networking opportunities.
For the first time, under authority of Section 32 of the Agricultural Adjustment Act Amendment of 1935, the U.S. Department of Agriculture will purchase up to $20 million of fresh mandarins and tangerines for distribution to food banks, schools and other non-conventional markets.
USDA also announced that it will purchase up to $20 million in oranges and $10 million in grapefruit as well.
In response to USDA’s announcement, California Citrus Mutual President Casey Creamer made the following statement, “Section 32 is an important procurement program that supports America’s farmers and provides domestic products to communities and schools. Twenty years ago, mandarins trailed all varieties of fresh citrus in per capita U.S. consumption. By 2025, however, it is anticipated that mandarins will overtake oranges as the most-consumed fresh citrus in the U.S.”
“USDA’s domestic nutrition programs should reflect this significant shift in citrus consumption by ensuring mandarins are made available to schools and food banks. This Section 32 purchase is an excellent first step to introducing mandarins to other procurement and food distribution programs in the future. California Citrus Mutual applauds the USDA Agriculture Marketing Service for their efforts to bring American grown mandarins and other citrus products to all consumers.”
The purpose of Section 32 is to encourage domestic consumption of U.S. food products by diverting them from conventional market channels. Information about the purchases, including the official solicitations and procurement specifications, is posted on the Agricultural Marketing Service’s website at www.ams.usda.gov/selling-food.
About California Citrus Mutual (CCM)
CCM is a voluntary, non-profit trade association representing California citrus growers on the economic, regulatory, and political issues that impact them most.
Maeli Melotto and her team at the UC Davis Department of Plant Sciences are looking for strains of lettuce that are genetically stronger at resisting bacteria that can make people sick. Their work has led to the identification of a gene that could play a role in the plant’s susceptibility to E. coli, a bacterium that causes potentially lethal intestinal illness.
Like all living organisms, vegetables need 
Hidden beneath the delicate, red skin and juicy flesh of a tomato is a wealth of nutrients and genetic makeup. With recent research on the first genome of a species in the tomatillo tribe (part of the tomato family), we now have a better idea of how this vital plant family came to be.
