Posts Tagged: greenhouse

Grape seeds, stems and skins can reduce dairy cattle emissions

A UC Davis-led pilot research project, to be detailed in a paper later this year, found that mixing in grape pomace reduced methane emissions, improved feed efficiency and increased healthful fats. Archive photo by Elena Zhukova

Low-cost wine industry additive also improved feed efficiency and milk quality

Researchers at University of California, Davis, added fresh grape pomace left over from winemaking operations to alfalfa-based feed for dairy cows and found that methane emissions were reduced by 10% to 11%.

The preliminary findings could offer a low-cost sustainable pathway for vineyards to reduce waste while helping dairy operations maintain quality while cutting back on emissions of methane, which is a powerful greenhouse gas.

“This is the first time anybody has shown that this can work in California,” said Ermias Kebreab, an animal science professor and associate dean of global engagement at UC Davis. “You're reducing emissions, you're improving the quality and it may also reduce the cost of production.”

The pilot research project, which will be detailed in a paper later this year, also found that mixing in grape pomace improved feed efficiency and increased healthful fats, said Selina Wang, an associate professor of Cooperative Extension in small scale fruit and vegetable processing.

“We found that the feed with the additive of grape pomace changed the fatty acid composition of the milk and, in particular, increased the polyunsaturated fats, which are the main fats in grape pomace,” Wang said. “This suggests that supplementing the feed with an optimal fatty acid profile may have positive impact on the fatty acid profile of the milk and increase their health benefits.”

Symbiotic commodities?

In 2022, California was the leading dairy producer in the country, generating $10.40 billion in sales, while 90% of wine production came from the Golden State, with a market value of $5.54 billion.

Processing grapes for wine generates thousands of tons of waste in the form of grape pomace, which consists of leftover seeds, skins and stems. Dairy and livestock are responsible for more than half of the state's methane emissions, owed largely to cow burps.

They are the top two agricultural commodities in California, according to state production statistics, and reducing waste and emissions for both industries are key to the state meeting its climate goals.

From left to right: wet, dry, and dry and ground grape pomace. Photo by Edwin Grey, UC Davis

Tannins for emission reductions

Wine grapes are high in fats and tannin, which is known to reduce methane emissions, so Kebreab sought to test if adding grape pomace to feed could have a positive effect while not adversely affecting production.

“It's a byproduct that's not being used much,” he said. “This is something that can be included in our efforts to try to reduce emissions.”

A mix of feed options

To do the research, scientists worked with Holstein dairy cows and gave the animals feed consisting of alfalfa, wheat, almond hulls, cottonseed and grain. After two weeks, the cows were split into three groups: A control group with no change in diet, another where the feed combination included 10% grape pomace and a third that received 15% grape pomace.

Every four weeks, the cow groups would change feed combinations.

They were fed twice daily by postdoctoral students and interns, and emissions were monitored daily. Milk production was documented in the morning and evening and milk samples were collected weekly to analyze for fat, protein, lactose and other measurements, which showed no differences between the control and other groups.

Methane and hydrogen emissions were reduced compared with the control group, suggesting that grape pomace reduced enteric emissions without affecting production.

“I think the dairy industry will be very interested in this,” Kebreab said. “Sometimes when you're using additives, they have palatability issues. With grape pomace, they absolutely love it.”

Next on the list is a trial with olive pomace and working to understand the mechanism that reduces emissions. “If we have a better understanding of the mechanisms, we can select the feed additive or a mix of feed additives to reduce dairy cattle emissions and make dairy milk healthier while making use of the agriculture byproducts,” Wang said. “There's a lot of room to grow in this space and we're excited about this work.”

The research was supported by the California Dairy Research Foundation.

This article was first published on the UC Davis news site.

UC Davis to build new $5.25M greenhouse to protect U.S. grapevine collection

A new greenhouse at UC Davis will be built to protect grapevines from diseases such as red blotch disease, which can cause leaves to turn red, hamper fruit ripening and reduce wine quality. Photo courtesy of Foundation Plant Services/UC Davis

Project designed to prevent red blotch and other grapevine diseases

A new, $5.25 million greenhouse is being built on the University of California, Davis, campus to safeguard an important grapevine collection from red blotch disease and other pathogens. 

The 14,400-square-foot greenhouse will have a vestibuled entry, be insect-proof and provide another level of disease protection. It is being spearheaded by Foundation Plant Services, or FPS, which provides the U.S. grape industry with high-quality, virus-tested grapevine plant material.

The program serves as the primary source for grapevine plant material distributed to nurseries under the California Department of Agriculture's Grapevine Registration and Certification Program, which provides the majority of grapevines planted in the United States. For the grape industry, it is essential to protect this material from disease-carrying insects and guarantee fast access to clean plant material.

“The program is considered the largest quarantine center for the grapevine industry in the United States,” said Maher Al Rwahnih, a plant pathologist and FPS director. “This is kind of a game changer for us.”

A history of serving the grapevine industry

FPS has maintained healthy grapevine planting stock on the UC Davis campus for more than 70 years in open fields at the Classic and Russell Ranch foundation vineyards. FPS scientists first detected grapevine red blotch virus at Russell Ranch in 2017. By 2021, an estimated 51.6% of the crop there was infected. Material from that vineyard is not being sold, and the site is now part of an epidemiological study to try to pinpoint how the disease is transmitted.

FPS pathologists have detected red blotch on less than 1% of the Classic vineyard crop. But it may not always be that way in the future.

“We don't know how long the Classic vineyard will remain clean,” Al Rwahnih said. “Every testing season, this is what keeps me up at night. We're not sure why it's happening in Russell Ranch and not the Classic vineyard.”

Once the greenhouse is operating, grapevines propagated from plant material from the Classic vineyard will be moved into the greenhouse, tested and verified as clean from disease. From there it will be sold to nurseries, which will grow additional plants to sell to growers.

Two greenhouses part of plan

Normally the foundation has 4,000 vines available, but the greenhouse will only house 2,000 vines, so inventory will be cut in half.

“This phase is just a starting phase,” Al Rwahnih said. “It's not sufficient for our needs.”

FPS plans to build another greenhouse in the next two to three years to increase capacity.

Industry groups and FPS identified greenhouses as the best way to protect the plants from red blotch and other pathogens transmitted by insects. They are also consulting with those same people on the grape varieties to include in the greenhouse.

“We have a large selection, and we need to make sure all the varieties that are important to industry are contained,” he said.

The first greenhouse is expected to be finished by the end of 2023.

Funding for the first greenhouse is coming from a variety of sources. The California Fruit Tree, Nut Tree and Grapevine Improvement Advisory Board, managed by the California Department of Food and Agriculture, contributed $4 million to the project. The California Grape Rootstock Research Foundation gave $500,000, Foundation Plant Services with UC Davis is funding $450,000, and the California Grape Rootstock Commission gave $100,000.

“This is crucial for the grapevine industry, and we are very grateful for the support,” Al Rwahnih said.

Innovating dairy digester research

Dr. Pramod Pandey, a faculty member and cooperative extension specialist at the UC Davis School of Veterinary Medicine runs experiments in capturing biogas.

California leads the nation in agricultural production, producing nearly all the nation's leafy green vegetables, most nut and fruit varieties, and is ranked first in egg and dairy production.

What that means is that California also produces a lot of agricultural waste materials, including lots of manure.

Historically these waste materials have been used as a rich source of compost. However, researchers at UC Cooperative Extension are researching innovative uses for this material. 

Dr. Pramod Pandey, a faculty member and Cooperative Extension specialist at the UC Davis School of Veterinary Medicine, focuses on better ways to manage waste material for both large and small farms. Dr. Pandey researches how to convert the organic matter in manure and other waste materials into a renewable energy source that can be used to power our state.

Converting manure to renewable energy

California gets over 27% of its energy from renewable resources like solar wind, and hydroelectric. Our goal is 50% renewable energy by 2030. California is taking steps towards this goal by building a network of dairy digesters which use bacteria to break down dairy manure and convert it into biogas. Clean burning fuels, such as biogas, are a sustainable source for generating energy because when they are burned, harmful by products are not produced.

Big bonus

A bonus is that the solid material left after the digesters have done their job is a fertilizer that can be used to grow the fruits, vegetables and nuts that our state is famous for. This type of fertilizer contains nutrients that are more readily available for plants because the digestion process breaks up organic materials more efficiently than traditional composting. The digestion process also helps reduce the number of harmful bacteria found in manure, making it much safer for use on plants grown for human food.

California leading in discovery and innovation

When we think about where agriculture has been and where it is going, innovation, efficiency and environmental sustainability are hallmarks of our approach in California. People like Dr. Pandey are driving forward research and technology to minimize the impact of agriculture production on the environment. When we think about where agriculture has been and where it is going, innovation, efficiency and environmental sustainability are hallmarks of our approach in California. His multidisciplinary approach to solving this complex problem of agricultural waste materials and water/air quality helps improve the economic wellbeing of farmers, and benefits Californians by providing nutrients for safe, healthy, and nutritious food.

While the importance of California's agriculture might be huge, its footprint on the environment doesn't have to be, and it is researchers like Dr. Pramod Pandey who are ensuring our state leads in discovery and innovation for many harvests to come.

Heather Johnson, Instructional Systems Designer, Gregory Wlasiuk, E-Learning Curriculum Designer, and Dr. Sara Garcia, Project Scientist, with the Western Institute for Food Safety and Security at the University of California, Davis, provided the script for the video which was used in this story. View Heather, Sara and Greg's filming and editing skills in the video below. Greg provides the narration. 

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