California Fruit and Vegetable

Category: Non-Video

  • CDFA Teams up with Partners to Introduce California Pollinator Coalition

    CDFA Teams up with Partners to Introduce California Pollinator Coalition

    A broad array of organizations from across California’s agricultural and environmental landscape today announced a working coalition to address their shared commitment to the health of wild and managed pollinators.

    The Coalition is focusing on increasing the value working lands provide to our environment, to benefit biodiversity and farmers alike. The California Pollinator Coalition, convened by Pollinator Partnership, the California Department of Food and Agriculture, and the Almond Board of California, includes more than twenty organizations–representing the large majority of California’s crop and range land–pledging to increase habitat for pollinators on working lands.

    Together, the goal is to increase collaboration between agriculture and conservation groups for the benefit of biodiversity and food production. The result will be on-the-ground improvements, technical guidance, funded research, documentation of relevant case studies, and tracked progress toward increasing healthier pollinator habitats.

    Achieving this bee friendly goal is laden with benefits for farmers and the environment in California, increasing biodiversity and sequestering more carbon in the soil.

    The Coalition also hopes its success will serve as a model for even more collaboration among interests who have not always been aligned, but who are willing to come together in partnership to confront common challenges.

    “What we are doing in California is acknowledging the urgency to address the critical issue of protecting all pollinators, including native and managed species,” said Laurie Davies Adams, President and CEO of Pollinator Partnership. “Agriculture and conservation must work together to achieve this goal, especially when we will be facing many of the same issues –increasing temperatures, erratic and unpredictable weather, fires, drought, soil depletion, and more. The outcome will not be a tidy report that sits on a shelf, but rather a metric of acres, projects, and species added to the landscape while agriculture continues to profitably feed the nation.”

    The collective land represented by coalition members will provide the critical mass to address habitat on an unprecedented scale, for the benefit of beneficial insects, such as bees, butterflies, beetles, wasps, moths and more. California is home to more than 1,600 native bees and hundreds of other species of pollinating insects. Globally, pollinators provide service to more than 180,000 different plant species, more than 1,200 crops, and are responsible for producing an estimated one out of every three bites of food. They sustain our ecosystems and support natural resources, all while adding $217 billion to the global economy each year.

    But pollinator populations are declining and often suffer from the same challenges as California’s agriculture. The Coalition will work together on a variety of fronts to support pollinators:

    •Preparing farmer-friendly guidance to buildand maintainpollinator habitat on farms and ranches

    •Promoting voluntary, incentive-based habitat establishment projects and Integrated Pest Management (IPM) practices

    *Conducting research and disseminating relevant science

    •Monitoring outcomes (adoption rates and effectiveness of practices)

    “Collaborative action can mitigate risks to California’s pollinators, and that’s exactly why this coalition has come together,” said Karen Ross, Secretary of California Department of Food and Agriculture. “We need urgent action, yet the first step in the process is building trust that encourages, enables, and enhances the result. The California Pollinator Coalition is a big step forward in a journey of grower and conservation groups voluntarily demonstrating leadership.”

    “This will not be an easy or quick fix,” said Josette Lewis, Chief Scientific Officer of the Almond Board of California. “It will require a robust and sustained effort, but we are determined to be part of the solution. Almond growers and many other farmers depend on pollinators to produce a crop and pollinators depend on us to provide safe habitat. Working lands can and should be part of the solution.”

    “Farm Bureau supports voluntary, farmer-friendly efforts to improve habitat for native pollinators, and we have long advocated improved research on pollinator health,” said Jamie Johansson, President of the California Farm Bureau. “We will work with the coalition for the benefit of native pollinators and managed bees, and to assure stability for the domestic bee business.”

    “Climate change will affect the wildlife of California and the way we grow food in many ways,” said Dan Kaiser, director of conservation at Environmental Defense Fund. “The best chance for biodiversity and farms to thrive is to rebuild the natural infrastructure that supports pollinators, soil health and water resilience throughout the Central Valley. This coalition will promote robust research and guidance to support a more resilient and biodiverse agricultural landscape.”

    While just beginning its work, the Coalition is catalyzing new collaborations and continuing to recruit partners who understand the urgency and share the common goal of supporting both the health of pollinators and agriculture. Current California Pollinator Coalition membership includes:

    • Agricultural Council of California
    • Almond Alliance of California
    • Almond Board of California
    • California Alfalfa and Forage Association
    • California Association of Pest Control Advisers
    • California Association of Resource Conservation Districts
    • California Cattlemen’s Association
    • California Citrus Mutual
    • California Department of Food and Agriculture
    • California Farm Bureau Federation
    • California State Beekeepers Association
    • California Sustainable Winegrowing Alliance
    • Environmental Defense Fund
    • Monarch Joint Venture
    • Monarch Watch
    • Pollinator Partnership
    • Project Apis m.
    • University of California Agriculture and Natural Resources
    • USDA Natural Resources Conservation Service of California
    • Western Growers
    • Dr. Neal Williams, University of California, Davis

    About the California Pollinator Coalition — The California Pollinator Coalition, convened by Pollinator Partnership, the California Department of Food and Agriculture and the Almond Board of California, is made up of a diverse group of agricultural and environmental organizations with the shared goal of providing enhanced habitat for pollinators. The Coalition and its members have pledged to increase habitat for pollinators on working lands. Additionally, the group plans to promote research and track its progress toward healthy and abundant habitats.

  • Healthy Roots, Healthy Trees: HLB & Soil Microbes

    Healthy Roots, Healthy Trees: HLB & Soil Microbes

    The rhizosphere, defined as the soil environment that surrounds the plant roots, is a rich and diverse habitat for microbes. Some members of the rhizosphere microbiome (or collection of microbes), are good, others bad while many are just there and don’t provide any benefits or harm to the host. One function of the good microbes in the rhizosphere is to help facilitate the availability and assimilation of nutrients and water from the rhizosphere. Just like the human gut, the plant rhizosphere conveys key nutritional functions and the analogy was made that “plants wear their gut on the outside”. One example is the symbiotic relationship between legumes (peas, beans) and rhizobia. Those bacteria help the plant fix atmospheric nitrogen in exchange for carbon supply. Another example is the symbiotic relationship between the plant and mycorrhizal fungi, whereby the mycorrhizae receive carbon from the plant in exchange for increased nutrient uptake (principally phosphorus and nitrogen). There is undeniable evidence that plants have developed a mechanism for recruiting good microbes to cope with environmental stress such as protection against opportunistic pathogens or drought. The rise of ‘omics’ technologies have helped profile entire microbial communities associated with plants and shed light in their biological functions. This research has fueled the development of novel commercial bioproducts to address the increasing consumer’s demand of environmentally-friendly products. As a result, there has been several commercial ‘probiotics’ and ‘prebiotics’ that have been marketed for agricultural use including many biocontrol agents such as fungal- (e.g., Trichoderma) and bacterial- based (e.g., Bacillus, Streptomyces, or Pseudomonas) bioproducts.

    One goal of my research program is to identify beneficial microbes for tree and vines crops, promote practices that support the presence and abundance of beneficial microbes and figure out how good microbes help combat pathogens and support plant health. As part of a collaborative project (UC Riverside, University of Florida, USDA-ARS) funded by the California Citrus Research Board and the USDA-NIFA, we profiled the microbiome of citrus trees in the context of Huanglongbing disease (or HLB). HLB is a highly destructive and lethal disease to all commercial citrus cultivars making it a threat to citrus production globally. Finding strategies that do not only rely exclusively on management of the insect vector of the bacterium (the Asian Citrus Psyllid), is a priority to the citrus industry. In our research, we found that there were significant tissue-specific microbial shifts occurring within the citrus microbiome as trees get sicker, especially in the root compartment. As HLB progressed, there were depletions of beneficial species in roots, such as mycorrhizal fungi, and enrichments of parasitic microorganisms, such as Fusarium and Phytophthora (see Figure). HLB-affected trees decline because of the clogging the phloem sieve tubes, which limit movement of sap and translocation of sugar to the roots, hence leading to feeder root collapse. Once tree is weakened, it becomes more susceptible to pathogens such as Phytophthora which further weakens the trees and exacerbate above ground HLB symptoms. In addition, several studies from Florida suggested that cultural practices that supported root health and rhizosphere microbiome richness and diversity limited root collapse.

    Figure: Citrus decline caused by HLB (https://apsjournals.apsnet.org/doi/10.1094/PBIOMES-04-20-0027- R – Ginnan et al. 2020. Phytobiomes); canopy thinning, wood dieback, feeder roots decline, collapse of beneficial microbes and enrichment of pathogens in roots.

    Our group was recently awarded another research funding by the USDA-NIFA Emergency Citrus Disease Research and Extension program (project director, M.C. Roper, Microbiology and Plant Pathology, UC Riverside). This research effort in collaboration with UC Agricultural and Natural Resources, UC Davis, University of Florida, and the USDA-ARS aims at investigating the root collapse associated with HLB- impacted trees and finding ways to mitigate it by promoting root health. In the proposed work, we will test how different sectors of the root microbiome contribute to or lessen fibrous root loss and if soil amendments (e.g., humic acid treatment, mulching) and planting of HLB tolerant rootstocks (Poncirus trifoliata and P. trifoliata hybrids) can be used to mitigate root loss associated with HLB in Florida, and how tree respond to those practices under a HLB free environment in California. While these approaches will not cure trees from HLB, it will provide a science-based information for strategies that support root and tree health and sustain orchard longevity until remedies are discovered. — By Philippe Rolsausen, Professor in Cooperative Extension, UC Riverside

  • Tarped Against Asian Citrus Psyllid

    Tarped Against Asian Citrus Psyllid

    Researchers at the California Data Analysis and Tactical Operations Center (DATOC) have analyzed Asian citrus psyllid (ACP) trapping data along major transportation routes before and after tarping regulations for bulk citrus shipments were enacted. The purpose was to determine the effectiveness of the policy.

    DATOC is an independent group of scientists sponsored by the Citrus Research Board and the California Citrus Pest and Disease Prevention Program. The group was formed in 2016 to create and amend tactical response plans for huanglongbing (HLB) suppression and management for California citrus.

    DATOC found a significant reduction in the rate of ACP finds throughout the San Joaquin Valley (SJV) after tarping regulations went into effect. The SJV contains more than 70% of California’s packinghouses. Coastal and Southern California counties ship more than 63 million pounds of bulk citrus into the SJV annually for processing.

    Source: Citrus Pest & Disease Prevention Program

    In years past, ACP populations have soared as they presumably “hitchhiked” on trucks that weren’t properly covered, coming from Southern California into the SJV and threatening the livelihood of commercial groves throughout California along the way. However, after the California Department of Food and Agriculture (CDFA) required tarping in 2017, DATOC data shows that tarping has effectively reduced ACP movement.

    While these results are encouraging, scientists say that growers must continue to remain vigilant. In a recent letter, Citrus Pest & Disease Prevention Committee (CPDPC) chairman Jim Gorden stated that ACP populations are expected to “flare up” occasionally, such as the late 2020 ACP detections in Kern, Madera, San Luis Obispo, Santa Barbara, Santa Clara, Tulare, Contra Costa and other counties.

    The CPDPC emphasizes that growers, packers, transporters and other stakeholders must continue to stay on top of this elusive ACP pest and the dangerous HLB disease it spreads. The upfront cost to manage ACP is much less than the potential hit to the citrus industry if HLB spreads throughout the state.

    In order to move bulk citrus from an ACP regional quarantine zone or a HLB quarantine area under the terms of the permit(s), growers, grove managers, haulers and harvesters must comply with the CDFA’s transporting requirement as detailed in their order. Get specific details here. — By Ben Faber, UCCE Advisor, Ventura & Santa Barbara Counties

  • With Climate Change Will We Grow Cactus (Biofuel, Food & Forage Crop)?

    Could cactus pear become a major crop like soybeans and corn in the near future, and help provide a biofuel source, as well as a sustainable food and forage crop? According to a recently published study, researchers from the University of Nevada, Reno believe the plant, with its high heat tolerance and low water use, may be able to provide fuel and food in places that previously haven’t been able to grow much in the way of sustainable crops.

    Global climate change models predict that long-term drought events will increase in duration and intensity, resulting in both higher temperatures and lower levels of available water. Many crops, such as rice, corn and soybeans, have an upper temperature limit, and other traditional crops, such as alfalfa, require more water than what might be available in the future.

    “Dry areas are going to get dryer because of climate change,” Biochemistry & Molecular Biology Professor John Cushman, with the University’s College of Agriculture, Biotechnology & Natural Resources, said. “Ultimately, we’re going to see more and more of these drought issues affecting crops such as corn and soybeans in the future.”

    Fueling Renewable Energy

    As part of the College’s Experiment Station unit, Cushman and his team recently published the results of a five-year study on the use of spineless cactus pear as a high-temperature, low-water commercial crop. The study, funded by the Experiment Station and the U.S. Department of Agriculture’s National Institute of Food and Agriculture, was the first long-term field trial of Opuntia species in the U.S. as a scalable bioenergy feedstock to replace fossil fuel.

    Results of the study, which took place at the Experiment Station’s Southern Nevada Field Lab in Logandale, Nevada, showed that Opuntia ficus-indica had the highest fruit production while using up to 80% less water than some traditional crops. Co-authors included Carol Bishop, with the College’s Extension unit, postdoctoral research scholar Dhurba Neupane, and graduate students Nicholas Alexander Niechayev and Jesse Mayer.

    “Maize and sugar cane are the major bioenergy crops right now, but use three to six times more water than cactus pear,” Cushman said. “This study showed that cactus pear productivity is on par with these important bioenergy crops, but use a fraction of the water and have a higher heat tolerance, which makes them a much more climate-resilient crop.”

    Cactus pear works well as a bioenergy crop because it is a versatile perennial crop. When it’s not being harvested for biofuel, then it works as a land-based carbon sink, removing carbon dioxide from the atmosphere and storing it in a sustainable manner.

    “Approximately 42% of land area around the world is classified as semi-arid or arid,” Cushman said. “There is enormous potential for planting cactus trees for carbon sequestration. We can start growing cactus pear crops in abandoned areas that are marginal and may not be suitable for other crops, thereby expanding the area being used for bioenergy production.”

    Fueling People and Animals

    The crop can also be used for human consumption and livestock feed. Cactus pear is already used in many semi-arid areas around the world for food and forage due to its low-water needs compared with more traditional crops. The fruit can be used for jams and jellies due to its high sugar content, and the pads are eaten both fresh and as a canned vegetable. Because the plant’s pads are made of 90% water, the crop works great for livestock feed as well.

    “That’s the benefit of this perennial crop,” Cushman explained. “You’ve harvested the fruit and the pads for food, then you have this large amount of biomass sitting on the land that is sequestering carbon and can be used for biofuel production.”

    Cushman also hopes to use cactus pear genes to improve the water-use efficiency of other crops. One of the ways cactus pear retains water is by closing its pores during the heat of day to prevent evaporation and opening them at night to breathe. Cushman wants to take the cactus pear genes that allow it to do this, and add them to the genetic makeup of other plants to increase their drought tolerance.

    Bishop, Extension educator for Northeast Clark County, and her team, which includes Moapa Valley High School students, continue to help maintain and harvest the more than 250 cactus pear plants still grown at the field lab in Logandale. In addition, during the study, the students gained valuable experience helping to spread awareness about the project, its goals, and the plant’s potential benefits and uses. They produced videos, papers, brochures and recipes; gave tours of the field lab; and held classes, including harvesting and cooking classes.

    Fueling Further Research

    In 2019, Cushman began a new research project with cactus pear at the U.S. Department of Agriculture – Agricultural Research Service’ National Arid Land Plant Genetic Resources Unit in Parlier, California. In addition to continuing to take measurements of how much the cactus crop will produce, Cushman’s team, in collaboration with Claire Heinitz, curator at the unit, is looking at which accessions, or unique samples of plant tissue or seeds with different genetic traits, provide the greatest production and optimize the crop’s growing conditions.

    “We want a spineless cactus pear that will grow fast and produce a lot of biomass,” Cushman said.

    One of the other goals of the project is to learn more about Opuntia stunting disease, which causes cactuses to grow smaller pads and fruit. The team is taking samples from the infected plants to look at the DNA and RNA to find what causes the disease and how it is transferred to other cactuses in the field. The hope is to use the information to create a diagnostic tool and treatment to detect and prevent the disease’s spread and to salvage usable parts from diseased plants. — By Claude Wharton, University of Nevada

  • With Climate Change Will We Grow Cactus (Biofuel, Food & Forage Crop)?

    With Climate Change Will We Grow Cactus (Biofuel, Food & Forage Crop)?

    Could cactus pear become a major crop like soybeans and corn in the near future, and help provide a biofuel source, as well as a sustainable food and forage crop? According to a recently published study, researchers from the University of Nevada, Reno believe the plant, with its high heat tolerance and low water use, may be able to provide fuel and food in places that previously haven’t been able to grow much in the way of sustainable crops.

    Global climate change models predict that long-term drought events will increase in duration and intensity, resulting in both higher temperatures and lower levels of available water. Many crops, such as rice, corn and soybeans, have an upper temperature limit, and other traditional crops, such as alfalfa, require more water than what might be available in the future.

    “Dry areas are going to get dryer because of climate change,” Biochemistry & Molecular Biology Professor John Cushman, with the University’s College of Agriculture, Biotechnology & Natural Resources, said. “Ultimately, we’re going to see more and more of these drought issues affecting crops such as corn and soybeans in the future.”

    Fueling Renewable Energy

    As part of the College’s Experiment Station unit, Cushman and his team recently published the results of a five-year study on the use of spineless cactus pear as a high-temperature, low-water commercial crop. The study, funded by the Experiment Station and the U.S. Department of Agriculture’s National Institute of Food and Agriculture, was the first long-term field trial of Opuntia species in the U.S. as a scalable bioenergy feedstock to replace fossil fuel.

    Results of the study, which took place at the Experiment Station’s Southern Nevada Field Lab in Logandale, Nevada, showed that Opuntia ficus-indica had the highest fruit production while using up to 80% less water than some traditional crops. Co-authors included Carol Bishop, with the College’s Extension unit, postdoctoral research scholar Dhurba Neupane, and graduate students Nicholas Alexander Niechayev and Jesse Mayer.

    “Maize and sugar cane are the major bioenergy crops right now, but use three to six times more water than cactus pear,” Cushman said. “This study showed that cactus pear productivity is on par with these important bioenergy crops, but use a fraction of the water and have a higher heat tolerance, which makes them a much more climate-resilient crop.”

    Cactus pear works well as a bioenergy crop because it is a versatile perennial crop. When it’s not being harvested for biofuel, then it works as a land-based carbon sink, removing carbon dioxide from the atmosphere and storing it in a sustainable manner.

    “Approximately 42% of land area around the world is classified as semi-arid or arid,” Cushman said. “There is enormous potential for planting cactus trees for carbon sequestration. We can start growing cactus pear crops in abandoned areas that are marginal and may not be suitable for other crops, thereby expanding the area being used for bioenergy production.”

    Fueling People and Animals

    The crop can also be used for human consumption and livestock feed. Cactus pear is already used in many semi-arid areas around the world for food and forage due to its low-water needs compared with more traditional crops. The fruit can be used for jams and jellies due to its high sugar content, and the pads are eaten both fresh and as a canned vegetable. Because the plant’s pads are made of 90% water, the crop works great for livestock feed as well.

    “That’s the benefit of this perennial crop,” Cushman explained. “You’ve harvested the fruit and the pads for food, then you have this large amount of biomass sitting on the land that is sequestering carbon and can be used for biofuel production.”

    Cushman also hopes to use cactus pear genes to improve the water-use efficiency of other crops. One of the ways cactus pear retains water is by closing its pores during the heat of day to prevent evaporation and opening them at night to breathe. Cushman wants to take the cactus pear genes that allow it to do this, and add them to the genetic makeup of other plants to increase their drought tolerance.

    Bishop, Extension educator for Northeast Clark County, and her team, which includes Moapa Valley High School students, continue to help maintain and harvest the more than 250 cactus pear plants still grown at the field lab in Logandale. In addition, during the study, the students gained valuable experience helping to spread awareness about the project, its goals, and the plant’s potential benefits and uses. They produced videos, papers, brochures and recipes; gave tours of the field lab; and held classes, including harvesting and cooking classes.

    Fueling Further Research

    In 2019, Cushman began a new research project with cactus pear at the U.S. Department of Agriculture – Agricultural Research Service’ National Arid Land Plant Genetic Resources Unit in Parlier, California. In addition to continuing to take measurements of how much the cactus crop will produce, Cushman’s team, in collaboration with Claire Heinitz, curator at the unit, is looking at which accessions, or unique samples of plant tissue or seeds with different genetic traits, provide the greatest production and optimize the crop’s growing conditions.

    “We want a spineless cactus pear that will grow fast and produce a lot of biomass,” Cushman said.

    One of the other goals of the project is to learn more about Opuntia stunting disease, which causes cactuses to grow smaller pads and fruit. The team is taking samples from the infected plants to look at the DNA and RNA to find what causes the disease and how it is transferred to other cactuses in the field. The hope is to use the information to create a diagnostic tool and treatment to detect and prevent the disease’s spread and to salvage usable parts from diseased plants. — By Claude Wharton, University of Nevada

  • San Joaquin Valley Olive Oil Competition

    San Joaquin Valley Olive Oil Competition

    The San Joaquin Valley Olive Oil Competition is back! Entries are now being accepted for the 2021 San Joaquin Valley Olive Oil Competition (SJVOOC)! Extra Virgin Olive Oil and Flavored Olive Oil entries from commercial producers in the State of California are eligible and olive oil must be made from producers’ most recent olive harvest. Deadline for entries is May 27, 2021.

    Awards will be given out for Gold and Silver medals in each category, as well as one overall “Best of Show” and one overall “Best of the Valley” award. Judging will be evaluated and scored as follows:

    • Gold Medal: Awarded to an olive oil that demonstrates its type and/or varietal character, balance, structure and complexities to the highest standards. Gold Medals will be awarded to those oils receiving scores between 86 – 100 points.
    • Silver Medal: Awarded to an olive oil reflecting the correct distribution of balance and character of its type or variety; an oil deemed to be well crafted and of excellent quality. Silver Medals will be awarded to those oils receiving scores between 76- 85 points.
    • Best of Show: Awarded to an olive oil recognized to possess special characteristics of the highest quality overall. Only gold medal winners are eligible to compete for Best of Show in their division.
    • Best of the Valley: Awarded to the oil that scored the highest with the ranch or office located in the San Joaquin Valley. Medals will be awarded for both EVOO and flavored oils. (Kern, Tulare, Kings, Fresno, Madera, Merced, Stanislaus and San Joaquin Counties eligible)

    Questions on entering? Email Stacy Rianda at srianda@fresnofair.com.

  • Early Season Retail Promotions Build Demand For California Avocados

    Early Season Retail Promotions Build Demand For California Avocados

    California Avocado Commission — Early demand for California avocados is high this year among targeted retailers, with both national chains and regional retailers indicating they are anxious for the start of the California avocado season. In past years, the season kicked off with “first of the season” Big Game or Valentine’s Day promotions at local specialty retailers. This year, due to market and harvest conditions, the early-season promotions at loyal retailer partners’ locations are instead focusing attention on spring and Easter.

    Both Gelson’s and Mollie Stone’s responded positively to the California Avocado Commission’s spring and Easter promotional plans, which include a combination of in-store display and sales contests partnered with robust online, social media and digital advertising campaigns. The Commission’s integrated promotional plans recognize that due to COVID-19 safety protocols retailers remain cautious about in-store promotions, such as demos, and that online marketing continues to play a primary role in marketing California avocados this season. Display and sales contests, which elevate in-store merchandising to draw attention to the fruit, also are important tactics in CAC customized retail programs.

    Gelson’s “Spring Into California Avocados” promotion ran from February 15 – 25. The upscale retailer hosted display and sales contests at its 27 Southern California locations, ensuring early season California avocados were front-and-center to announce the start of the long-anticipated season. Mollie Stone’s Easter promotion runs from March 22 – April 4, and includes sales and display contests at the retailer’s nine locations throughout the San Francisco Bay area. Both retail chains feature Commission display bins and signage.

    For both retailers, the in-store contests are complemented by value-added social media promotions created by the Commission. Posts on the retailers’ social media platforms showcase California avocado centric recipes, photos and messaging that celebrates the availability of fresh California avocados as we swing into spring. The social posts play a critical role in expanding the reach of the Commission’s messaging, promoting the fruit’s versatility in meals and snacks, touting California avocados’ nutritional qualities and showcasing the premium character of this locally grown fruit.

  • Adding ACP-Effective Materials to Suppress Kern County HLB Vectoring Pest in Citrus

    Adding ACP-Effective Materials to Suppress Kern County HLB Vectoring Pest in Citrus

    ACP/HLB San Joaquin Valley Task Force – To Citrus Growers in the Kern County area: last fall and early this year, there has been a significant number of Asian citrus psyllid (ACP) trap detections (over 100) in Kern County. The detections occurred in residential properties, as well as commercial citrus areas in Kern County – especially the City of Bakersfield and areas south and east of it. Unfortunately, in addition to the trap detections, live breeding populations of ACP were discovered by CDFA survey crews in both residential and commercial citrus. Although these detection areas were treated, there is significant concern low level ACP populations may still exist undetected and left to build on the new spring flush. It is imperative for us to continue our efforts to protect Kern County citrus from the devastating effects of Huanglongbing (HLB) – especially in light of the significant level of HLB-positive citrus trees found just south in Los Angeles, Orange, San Bernardino and Riverside counties. An established population of ACP increases the threat of HLB but will also cause the need for additional insecticide treatments to try to suppress the population. Additionally, if HLB is detected and confirmed by CDFA, critical regulatory changes may affect everyone. Given the posed risks, it is important the San Joaquin Valley keep ACP populations as close to eradicated as possible.

    The San Joaquin Valley ACP/HLB Area-Wide Task Force has been tracking and analyzing all ACP detections to date in Kern County. After recent review of the data, the Task Force strongly recommends growers add an ACP-effective material to their pre-bloom or spring foliar treatments – the sooner, the better since ACP build populations on the young leaf flush.  Fortunately, this timing coincides with pre-bloom treatments and treatments for katydid, worms, thrips and other pests.  See below for material examples from the University of California.

    IMPORTANT: If there is any open bloom in the orchard, state bloom regulations and pesticide label pollinator protections must be followed.  Contact the Kern County Agricultural Commissioner’s Office for details at (661) 868-6300.

    WHAT WE NEED YOU TO DO:

    1. Consider treating ALL your citrus blocks in Kern County, especially if they are located east and south of Bakersfield – including non-bearing trees and blocks not normally treated at this time.
    1. Use an ACP-effective insecticide next time you are treating the block. The sooner, the better – click on the link below for a list of ACP-effective insecticides from the University of California: Asian Citrus Psyllid / Citrus / Agriculture: Pest Management Guidelines / UC Statewide IPM Program (UC IPM) (ucanr.edu)

    Examples of ACP-effective materials which also suppress Katydids (from the UCIPM Guidelines):

    • Danitol
    • Baythroid
    • Mustang
    • Micromite
    • Entrust

    Examples of ACP-effective materials that can be used during the bloom period – some with restrictions (ALWAYS check the pesticide label and state bloom regulations prior to use):

    • Sivanto
    • Sefina
    • Micromite
    • Beleaf
    • Fujimite
    • ** = Restricted use to only 1 hour after sunset until 5 hours before sunrise.
    • **Delegate
    • **Entrust
    • **Exirel
    1. Suggested Dilution – 100 to 300 g.p.a. for airblast sprayers. FYI – many nutritional products are compatible with ACP insecticides however you should always check with your PCA before tank mixing.
    1. Please treat the borders of the block first, if possible, since ACP tend to populate block borders first. This way ACP will be driven toward the center of the block where they will get treated instead of away from the block and miss treatment.

    By adding an ACP-effective material to your spring foliar treatment, we will greatly lower both the ACP population and the risk of HLB being transmitted into our trees. Please let me know if you have any questions or concerns regarding this important effort by the SJV ACP/HLB Area-Wide Task Force.

    Sincerely,
    The ACP/HLB San Joaquin Valley Task Force

    For additional information on Kern County operations, please contact:
    Judy Zaninovich
    ACP/HLB Grower Liaison for Kern County
    (559) 730-8691
    jsleslie@msn.com

  • Fabled Silk Road Could be the Route to Better Apples

    Fabled Silk Road Could be the Route to Better Apples

    The Silk Road – the 4,000-mile stretch between China and western Europe where trade flourished from the second century B.C. to the 14th century A.D. – is responsible for one of our favorite and most valuable fruits: the domesticated apple.

    Snack-packing travelers would pick apples at one spot, eat them and toss their cores many miles away. The seeds grew into trees in their new locations, cross-bred with the wild species and created the more than 7,000 varieties of apples that exist today.

    Hybridizations with wild species have made the apple genome very complex and difficult to study, but a team of multi-disciplinary researchers – co-led by Zhangjun Fei, faculty member at the Boyce Thompson Institute, and Gan-Yuan Zhong, a scientist with the U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS) in Geneva, New York – tackled this problem by applying cutting-edge sequencing technologies and bioinformatics algorithms to assemble complete sets of both chromosomes for the domesticated apple and its two main wild progenitors.

    The team’s research is described in a paper published Nov. 2 in Nature Genetics, with authors from BTI, Cornell, the USDA and Shandong Academy of Agricultural Sciences.

    The researchers found that the apple’s unique domestication history has led to untapped sources of genes that could be used to improve the fruit’s size, flavor, sweetness and texture.

    “Plant breeders could use this detailed information to improve upon traits that matter most to consumers, which today is primarily flavor,” said Fei, also an adjunct associate professor in the College of Agriculture and Life Sciences’ School of Integrative Plant Science.

    “Perhaps more importantly,” he said, “the information will help breeders produce apples that are more resistant to stress and disease.”

    Fei said the new study was the outgrowth of an earlier collaboration, published in Nature Communications in 2017, which traced the history of apple domestication and evolution along the Silk Road.

    Follow-up discussions among Fei, Zhong and other colleagues at Cornell inspired them to build better apple reference genomes by applying new sequencing and assembly technologies to material in USDA’s Geneva Clonal Repository, which houses the largest collection of apple accessions in the world. Many of these accessions can be traced back to the Silk Road.

    In the current work, the researchers sequenced, assembled and compared the full reference genomes for three apple species: Gala, a top commercial cultivar of Malus domestica; and apple’s two main wild progenitors – the European crabapple (M. sylvestris) and the central Asian wild apple (M. sieversii), which together account for about 90% of the domesticated apple’s genome.

    The results provide apple breeders with detailed genomic roadmaps that could help them build a better apple.

    “We wanted to develop new genomes, especially the wild progenitors, because of the tremendous impact they could have on understanding apple’s genetic diversity and identifying useful traits for breeding new cultivars,” said Zhong.

    By comparing the three genomes, the researchers were able to identify which progenitor species contributed the genes responsible for many traits in the domesticated apple.

    For example, the team found that the gene giving apple its crunchy texture is located near the gene that makes it susceptible to blue mold.

    “Now that we know exactly where those two genome regions are,” Fei said, “breeders could figure out a way to keep the texture gene and breed out or edit out the blue mold gene to produce a more disease-resistant cultivar.”

    The team also assembled pan-genomes for the three species. A pan-genome captures all of the genetic information in a species, unlike a reference genome that captures one individual organism. Pan-genomes are especially important for a very diverse species like apple.

    The team identified about 50,000 genes in the pan-genome of the domesticated apple, including about 2,000 that were not present in previously published reference genomes for apple species. “These ‘missing genes’ turn out to be really important, because many of them determine the traits of greatest interest to apple breeders,” Fei said.

    Using RNA extracted from different stages of Gala fruits, they also identified genes linked to texture, aroma and other fruit characteristics that were preferentially expressed between the two copies of the genes.

    “That provides us and breeders with an even deeper understanding of the genetic diversity underlying a particular trait,” Zhong said. “The findings will help our group better manage and curate more than 6,000 apple accessions in the USDA Geneva Clonal Repository, as well as enable us to provide critical genetic and genomic information associated with the accessions to breeders and other researchers.”

    The team is planning on sequencing other wild apple species, which Fei said may have valuable traits that could improve stress-resistance and resilience in the domesticated apple.

    The research was supported by the USDA-ARS and by the National Science Foundation. — By Michael J. Haas, Boyce Thompson Institute

  • Gene Discovery May Help Peaches Tolerate Climate Stress

    Gene Discovery May Help Peaches Tolerate Climate Stress

    A team led by a Boyce Thompson Institute researcher has identified genes enabling peaches and their wild relatives to tolerate stressful conditions – findings that could help the domesticated peach adapt to climate change.

    The study, co-led by Boyce Thompson Institute faculty member Zhangjun Fei, examined the genomes of peach’s wild relatives and landraces – varieties that have adapted over a long time to specific local conditions – from seven regions in China. They identified genes responsible for peach’s tolerance to multiple environmental factors, including cold, drought and ultraviolet (UV-B) radiation levels at high altitudes.

    “Our study provides many candidate genes, showing how peach has adapted to all kinds of environmental stresses and stimuli,” said Fei, who is also an adjunct professor in the School of Integrative Plant Science. “Breeders can use this information to develop more resilient domesticated peach trees that cope better with temperature extremes, drought and other harsh, changing conditions imposed by climate change.”

    The research is described in a paper published March 9 in the journal Genome Research, with authors from BTI, the U.S. Department of Agriculture, the Chinese Academy of Agricultural Sciences, and the Institute of Agrifood Research and Technology in Barcelona. Lirong Wang, a professor at the Chinese Academy of Agricultural Sciences, co-led the work with Fei.

    Over the past decades, climate change has made many food crops less productive, highlighting an urgent need to make them more resistant to climate stressors. Many studies have identified the genes that enable rice, soybean and other food crops to adapt to their local environments. But few studies have looked at major fruit crops like the domesticated peach (Prunus persica), which has an annual global yield of 24.5 million tons.

    Many of domesticated peach’s adaptation genes have been lost as humans bred the plant to focus on flavor, sweetness and other traits. However, peach’s wild relatives and landraces harbor great genetic diversity that could provide resources for improving the resilience of their domesticated cousin.

    The researchers gathered 263 peach wild relatives and landraces – 218 from the National Peach Germplasm Repository of China and 45 from the Tibetan Plateau. The team then conducted genome-wide environmental association studies on the samples, and identified more than 2,700 spots in the genome that are linked to 51 environmental factors affecting the local climates of those regions.

    For example, peaches from a region with extremely low winter temperatures had a genetic variation in the histidine phosphotransfer protein AHP5, suggesting the variant gave the peach tree the ability to resist cold. The team confirmed this idea by showing levels of the protein increased when the plants were subjected to low temperatures.

    Plants from a very arid region harbored variants in multiple genes in the abscisic acid (ABA) biosynthesis pathway that regulates drought stress responses, and in 12 genes on pathways that regulate starch and sugar metabolism. Further experimentation showed that in response to drought stress, ABA induced higher levels of a sucrose-producing enzyme, thereby explaining why fruit from the peach trees in this region have consistently higher sugar contents than fruit from less arid regions.

    “When a fruiting plant like peach is growing under a stressful condition like drought, its fruit gets sweeter,” Fei said. “In this study, we have found the direct genetic link between drought and the sugar content of peach.”

    In the peach trees from the Tibetan Plateau, the team identified a variant in chalcone synthase 2 associated with tolerance to the intense UV-B radiation of that high-altitude region. The variant increased the production of the purple-colored flavonoid anthocyanin in the plant’s new shoots, protecting them from UV-B radiation damage.

    “Overall, the genetic information we found could help people breed peach trees that grow in many different and harsh environments, expanding peach’s geographic range to new regions,” Fei said. “Breeders could develop cultivars that thrive on otherwise unused land, bolstering the local economy and bringing more good food to local markets.”

    Climate change has also affected many temperate flowering and fruiting species, including peach, by causing them to bloom earlier. The team analyzed 89 peach samples spanning three decades (1983-2011) from one region in China, and found that bloom dates had advanced by about 10 days over that period. They also identified a potential genetic explanation for this advance: a variation in a circadian clock gene, LNK1, which is up-regulated by warm temperatures and highly expressed during blooming.

    “This finding could eventually let breeders control the bloom date of their trees, so that the peach crop is ready for harvest when the grower and the market are ready,” Fei said.

    The research was supported by grants from the U.S. National Science Foundation, the Agricultural Science and Technology Innovation Program, the National Natural Science Foundation of China, Huazhong Agricultural University and the Crop Germplasm Resources Conservation Project. — By Michael J. Haas, Boyce Thompson Institute