Grapevine red blotch virus, a disease that is dramatically reducing the value of winegrapes in California's premium wine production region, is harming plants by inhibiting photosynthesis in the leaves, according to research published this month in the Journal of Agricultural and Food Chemistry.
The new research also showed that infected vines weren't able to conduct water effectively, leaving whatever sugar that was created by photosynthesis stuck in the leaves. The accumulation of sugar in the leaves results in reduced sugar in the berries and lower-quality wine, said UC Cooperative Extension specialist Kaan Kurtural, one of the study authors.
According to the report, sucrose and its monosaccharides were the vast majority of soluble sugars found in the leaves. The leaf sugar tended to decrease in the ripening process on red blotch negative vines. But this was not the case in red blotch positive vines. As a result, grapevines infected with the virus produce winegrape clusters with reduced sugar content, poor color development and increased acidity.
Kurtural said the research will inform winegrape growers as they consider possible treatments in vineyards with grapevine red blotch-infected vines.
“There are some treatments that are being offered to growers, but now that we better understand the disease, we know they won't help,” Kurtural said. “Growers don't have to replace the infected vineyards immediately. But if 40 percent of vines are infected, they may want to consider replanting. At least now we know what the disease does, so they won't pay for snake oils.”
Grapevine red blotch virus was first discovered in the Oakville Experiment Station, UC Davis' research vineyard in Napa Valley, in 2008. Since then, researchers found the virus in grapevines throughout California and in 11 other states.
For the new research, the scientists compared naturally infected winegrape vines at the Oakville Station on two rootstocks – 110 R and 420 A – with vines grown on those two rootstocks that were not infected. Grape clusters were collected to examine differences in berry weight, titratable acidity, pH and total soluble solids.
“All those characteristics are important for wine quality,” Kurtural said. “Acidity and pH effect palatability and storage potential. Berry weight and soluble solids impact the physical characteristics of the wine.”
The grapevine red blotch virus impact on anthocyanidins and tannins are a still greater concern for winegrape growers as they change the flavor profiles sought in premium wines.
“High-value winegrapes are sold between $7,000 to $23,000 a ton. If the winegrapes don't have the profiles that wine makers are looking for, they may only be valued between $1,500 to $2,000 per ton,” Kurtural said.
The research was conducted by UC Davis post-doctoral students Johann Martinez-Buscher, Cassandra Plank, Runze Yu and Luca Brillante in collaboration with Kurtural, UCCE viticulture specialist Anita Oberholster, UCCE advisors Monica Cooper and Rhonda Smith and UC Davis Foundation Plant Services academic administrator Maher Al-Rwahnih.
A $4.6 million grant to UC Merced and UC Irvine will help UC Agriculture and Natural Resources researchers develop new tools and methods for California land owners to better manage the state's forests, shrub lands and grasslands.
California's Strategic Growth Council agreed to fund the Innovation Center for Advancing Ecosystem Climate Solutions, a three-year program co-led by UC Merced Professor Roger Bales and UC Irvine Professor Michael Goulden. The money comes through California Climate Investments, a statewide initiative that puts billions of cap-and-trade dollars to work
The goals include reducing wildfire risk, improving long-term carbon sequestration and bolstering resilience in the face of climate change, with an emphasis on California's rural regions and low-income communities.
“Our part of the project is to work with stakeholders and identify areas where we can focus management practices to promote healthy forests, minimize wildfires, improve water security and increase carbon sequestration,” said Toby O'Geen, UC Cooperative Extension soil resource specialist at UC Davis.
“Right now, many of California's forests, shrub lands and grasslands are carbon sources, and we need to change them into carbon sinks,” said Bales, director of the Sierra Nevada Research Institute and distinguished professor of engineering. “Our research will address information bottlenecks to guide decision making, build local capacity for science-based land management and develop methods for translating benefits of land restoration into financing for land restoration.”
California's recent drought, tree die-offs, wildfires and rising temperatures all point to the necessity of improved forest stewardship, Goulden said.
“Officials in the state government and agencies recognize this need, but uncertainty over how to proceed has sometimes slowed progress,” he said.
Most of the work will be conducted by scientists at Merced and Irvine, but collaborators from UC Berkeley, UC Davis, Stanford University, San Diego State University and the University of California Division of Agricultural and Natural Resources, as well as state agencies, will play important roles.
“This research will enable UC Cooperative Extension advisors to provide better advice to land managers to reduce the severity of wildfires,” said Glenda Humiston, UC vice president for agriculture and natural resources. “Severe wildfires are not only releasing greenhouse gases, but polluting the air of many communities, aggravating the health of people in less-affluent, inland areas such as Tulare, Yuba and Mariposa counties.”
At UC Merced, an interdisciplinary group of researchers from two departments — Civil & Environmental Engineering and Management of Complex Systems — will collaborate with UC Cooperative Extension and engage with local stakeholders. The group will study and identify the most-effective land-management practices, in terms of water conservation, forest health, fire resistance and carbon capture.
“We will develop the spatial data and analysis tools to plan landscape restoration, develop local capacity for better managing the state's wildlands in a warming climate, and enumerate the greenhouse gas and other benefits from investments in land management,” Bales said.
Goulden, professor of Earth systems science, said UC Irvine researchers will use a big-data approach to analyze observations collected by satellites since the 1980s to measure the efficacy of thousands of past and ongoing forest treatments, while UC Merced takes a different approach.
“We will work with groups in rural communities to systematically evaluate how well, or poorly, our products can support decision making,” Bales said, “and then develop both implementation pathways and policy recommendations to better and more-quickly implement landscape-restoration and carbon-capture projects across the state.”
Because there are critical gaps in the understanding of carbon cycles, uptake by forests and negative feedback from climate change, this project initiative has been established to develop new knowledge through measurements and modeling. Researchers will synthesize the resulting data to produce actionable information for stakeholders.
Bales and Goulden agreed the Innovation Center will target low-risk, high-yield opportunities to reduce California's greenhouse-gas contributions.
Just a small improvement in management efficiency will have meaningful benefits — on the order of several million metric tons of CO2 per year, Goulden said.
The program will also benefit low-income communities in the state by reducing wildfire risk, which disproportionately impacts poorer areas in California by maintaining water quality through better vegetation management; by fostering tourism in disadvantaged locales; and by preparing students in these areas for careers in sustainability and climate resilience.
UC Cooperative Extension cropping systems specialist Jeff Mitchell is issuing a standing invitation to the public to visit the site of an ongoing conservation agriculture research project and see for themselves the results of long-term soil-building practices.
“Every Friday morning from 9 o'clock till noon, beginning in February and going through June, I invite folks to come to the project site to see up close and personal just what soil health means,” Mitchell said.
The research site is at the University of California's West Side Research and Extension Center, 17353 W. Oakland Ave., in Five Points.
“I promise to be out there every Friday morning from Feb. 15 through June 26,” Mitchell said.
The project, funded by the National Research Initiative, compares plots that have been managed for more than 20 years in an annual rotation of cotton, processing tomatoes and more recently sorghum, garbanzos and melons, under four different treatments: no-tilled plus cover crops, no-tilled with no cover crops, conventionally tilled with cover crops and conventionally tilled without cover crops.
“What we've got at this site is a very long-term example of exactly what implementation of a small set of soil care, or soil health, principles really means for soil function and management,” he said.
Mitchell says that the study site in Five Points is a valuable resource for the people of California because of its dedicated adherence to principles that are widely touted to improve production efficiencies, reduce dust emissions, sequester carbon and reduce inputs over time.
“I recently heard about the value of publicly showcasing long-term sites such as the one we've got in Five Points. It's being done in several other places, including the Dakotas and in Europe,” Mitchell said. “It just seems to make sense to open up our field more widely to folks who might be interested in seeing the remarkable changes we've seen and monitored for a long time.”
According to Mitchell, the NRI Project field is already “the most visited research field in the state,” but with this new invitation, he is hoping to have a still broader impact. “We've got a simply amazing resource here and I want folks to see it,” he said.
The study has been selected as one of the monitoring sites of the North American Project to Evaluate Soil Health Measurements that has been initiated by the Soil Health Institute of Morrisville, N.C. More than 20 peer-reviewed scientific articles have been published based on work done in this study field.
While scientific reports continue to mount confirming that global climate change is increasing temperatures, causing more frequent weather extremes and raising the sea level in California, UC Cooperative Extension is working to ensure the worst predictions are avoided and California residents and businesses will be able to adapt to the change.
Each year, a diverse group of UC Agriculture and Natural Resources academics and program implementation professionals meet to share and collect the latest climate change experiences, ideas, science and solutions. The team works with farmers across the state to improve production practices and minimize environmental impact, conduct agricultural and natural resources conservation research, and coordinate programs like California Naturalist and UC Master Gardener, which recruit and educate volunteers to reach out to communities statewide to extend research-based information.
Reaching real people
In 2019, extension practitioners explored new approaches to delivery of information and services. For example, the first speaker addressed the way climate change impacts may be viewed through the lens of African-American or First Nation experiences, influenced by poverty, historical trauma and even spirituality.
Theopia Jackson, clinical psychologist at Saybrook University in Oakland, encouraged the team to consider whether assisting Americans navigating the changing climate or suffering the consequences of extreme weather events have “the bandwidth to take in one more helping hand.” Jackson has a long history of providing therapy services, specializing in serving populations coping with chronic illness and complex trauma.
Jackson suggested helpers ask themselves, “Are we inadvertently causing more stress than good? Do I have a sense for what they are already dealing with before bringing something new into the community?”
Jackson said the conversation about climate change in many communities might be more productive focused less on whether climate change exists or not, and instead on how to “join with them around the human experience.”
“If I'm trying to ‘talk them into it,' I need to step back,” Jackson said. “The conversation could be about scarcity or lifestyle. We need to find a way to join and hope they will get it before we've done irreversible damage.”
The careful selection of terminology and approach in climate change conversations was also raised by Dan Sonke, director of sustainable agriculture for Campbell's Soup. The company's primary and best-known product is soup, but it owns other familiar brands, including Pepperidge Farms, Snyder Pretzels, Kettle Chips and Emerald Nuts.
In California, Sonke works closely with farmers producing fresh produce to be used in Campbell's products, particularly processing tomatoes. During his career, he also worked in Campbell's marketing, based on its “corporate purpose.”
“We make real food for real people,” says the Campbell's corporate purpose. “People love that our food fits their real lives, fuels their bodies, and feeds their souls. And they appreciate knowing what goes into our food, and why — so they can feel good about the choices they make, for themselves and their loved ones.”
Sonke was hired to increase the use of sustainable farming practices by the company's producers and help farmers apply for grant funding from the state to implement climate-smart irrigation practices. The company was able to track a 20 percent reduction in water use and document a significant reduction in the emission of nitrous oxide, a greenhouse gas. The program is successful, but isn't driving their farmer communications or soup sales, Sonke said.
“Farmers don't think in terms of climate change, but they respond to what they know,” Sonke said. “Consumers don't respond to climate change adaptation in terms of what products they buy. They respect sustainability, but have no understanding of ‘sustainable agriculture' and ‘carbon sequestration.'”
Growing UCCE climate mitigation, adaptation and resilience programs
UC ANR is working on new ways to reach out to farmers and the public with information on climate change. Six community education specialists have been hired and four more are being recruited to work in counties around the state to help farmers access programs that will help them reduce greenhouse gas emissions on farms and dairies, build resilience to climate change and increase profit.
The Climate-Smart Farming Program is a collaborative effort with the California Department of Food and Agriculture focused on implementing on-farm solutions to improve soil health, nutrient management, irrigation management, on-farm composting and manure management.
The CDFA programs involved are:
- State Water Efficiency and Enhancement Program
- Healthy Soils Program
- Alternative Manure Management Program
The new community education specialists are already deployed in Mendocino, Glenn, Yolo, Santa Cruz, Ventura and San Diego counties. The four positions under recruitment will serve Imperial, San Joaquin, Fresno and Kern counties. To get information about these programs, contact:
- Fresno County, UCCE advisor Dan Munk, firstname.lastname@example.org
- Glenn County, UCCE advisor Betsy Karle, email@example.com
- Imperial County, UCCE advisor Oli Bachie, firstname.lastname@example.org
- Kern County, UCCE advisor Brian Marsh, email@example.com
- Mendocino County, UCCE advisor Glenn McGourty, firstname.lastname@example.org
- San Diego County, UCCE advisor Laurent Ahiablame, email@example.com
- San Joaquin County, UCCE advisor Brent Holtz, firstname.lastname@example.org
- Santa Cruz County, UCCE advisor Mark Bolda, email@example.com
- Ventura County, UCCE advisor Ben Faber, firstname.lastname@example.org
- Yolo County, UCCE advisor Morgan Doran, email@example.com
To reach a broad swath of California residents with research-based information on climate change mitigation and adaptation, UC ANR's California Naturalist program is leveraging its well-established partnerships with formal and informal science education institutions across the state to create a legion of climate stewards. At the team meeting, CalNat coordinator Greg Ira announced that the California Naturalist program has hired an academic coordinator to develop curriculum that will allow existing partners to deliver the material as part of the California Naturalist program. The graduates of this California Naturalist course focused on climate change will be encouraged to engage in volunteer service that helps build community resilience to climate change. These include participation in local adaptation planning efforts, community and citizen science projects, or addressing issues of social justice. The coordinator begins Feb. 19.
Renata Brillinger of the California Climate Action Network shared optimistic thoughts about the opportunities for climate change mitigation, adaptation and resilience. In terms of politics, she said California leadership has accepted climate change as a settled matter and are supportive of programs to address the issue. At the federal level, it is not easy to talk about climate change, but “that will change,” she assured.
Brillinger said biodiversification of California is an exciting area for climate change adaptation. Research is needed to understand how to shift crop locations for future production, and determine where, for example, water-intensive crops or orchards with chill requirements should be grown. More information is needed, she said, on how healthy soil will relate to climate resilience in agriculture.
“We have to reinvest in extension and Resource Conservation Districts,” Brillinger said.
Other possible climate change outcomes in California may be returning farmland to less-intensive uses, such as grazing. Fallowing land was one way that the agriculture industry coped with the drought of 2011-16, and implementation of the Sustainable Groundwater Management Act – a direct result of the drought – is estimated to take 1 million acres of farmland out of production. This approach won't be a solution for all farmers and ranchers, said David Lile, UC Cooperative Extension natural resources advisor.
“Ranchers and farmers interested in long-term sustainability, keeping the farm in place, will need help to integrate competing forces,” Lile said. “Economics will not be the only driving force.”
Cannabis is unlike any other agricultural crop. Because of its circuitous history — once illegal to grow, and now legal but heavily regulated — cannabis has cast a unique footprint on the environment and the communities of farmers who grow it.
UC Berkeley's new Cannabis Research Center, announced today by a multidisciplinary team of faculty, will explore how cannabis production impacts the environment and society, and how these impacts will evolve under new regulations set in place by legalization.
While other research groups in the University of California are focusing on the individual and public health ramifications of cannabis, the center will be the first in the UC system to explore oft-overlooked dimensions of cannabis growth.
Berkeley News spoke with center co-directors Van Butsic and Ted Grantham, both assistant cooperative extension specialists in UC Berkeley's Department of Environmental Science, Policy and Management, to learn more about the state of cannabis production in California and the center's goals.
Ted Grantham: My research primarily focuses on the impacts of water use. These farms are taking water directly from streams or from groundwater wells connected to streams. Most farms are located in smaller watersheds, so even though the total amount of water taken can be small, it can have a big impact on streams that support sensitive species, such as salmon. Other potential ecological impacts relate to the use of pesticides and fertilizers, and habitat fragmentation from building roads and clearing trees.
The social scientists in the center are also concerned about equity and the sustainability of growing communities. Historically many growers would be characterized as small-scale, and there is concern that through this process of legalization, there is going to be a consolidation of cannabis production following models of industrial agriculture. We are trying to understand if there is a way to have cannabis cultivation continue to sustain local economies and rural communities, while limiting impacts to the environment.
How have legalization and associated regulations affected cannabis production so far?
Van Butsic: We're about a year into the formal legalization of recreational cannabis production and it has been a rocky start. There have been fewer participants in the market — producers — than were anticipated. Some growers appear to have gone out of production, many appear to remain in black market production and a relatively small subset of growers have gone through the process of compliance. And the grower community that has pursued legal production are very vocal about the issues and challenges facing their group. We have been trying to better understand what are the barriers to compliance and, ultimately, if there can be changes made in policies that can really help to catalyze this transition.
Van Butsic: This is a great system to study really big sustainability problems. How do we develop an agricultural system that's good for the environment and good for farmers? And cannabis is a really interesting spot to look at it because the regulations enforcing cannabis are totally different than in the rest of agriculture, so it would be really interesting to see if we get different outcomes.
How do regulations differ between cannabis production and the rest of agriculture?
Van Butsic: Cultivators need to be permitted by the state water board, by local government and by state government to grow cannabis legally, and there are environmental regulations in all three of those levels that they need to comply with that require a higher order of environmental performance than most other agricultural crops.
So you think that understanding these regulations might help you apply them to other types of agriculture?
Van Butsic: Exactly. Agriculture has been notoriously difficult to regulate in the past, and this is a system where the regulators got the upper hand, and so it will be interesting to see how the producers respond, and if cannabis producers can be profitable and meet these super-high environmental performance measures, then perhaps there is knowledge and technology that can transfer from the cannabis industry to the rest of agriculture that can improve environmental performance of food production.
We are working on a big project right now where we are mapping where all the farms are after the latest regulatory changes. We want to know, if we could take down these barriers and everybody became compliant, what would that mean for local water budgets, environmental health and for the amount of cannabis that would be produced?
Ted Grantham: This is a rapidly changing industry, and no one really knows where it is headed. Everyone is playing catch up to a certain extent, and we believe researchers have an important role in bringing independent scientific information to conversations around cannabis policy./span>