- Author: Claude Wharton
medias contact: whartonc@unr.edu
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.
Among three cactus varieties researched by the University of Nevada, Reno as drought-tolerant crops for biofuel, Opuntia ficus-indica produced the most fruit while using up to 80% less water than some traditional crops. And spineless too.
Photo by John Cushman, University of Nevada, Reno.
https://onlinelibrary.wiley.com/doi/10.1111/gcbb.12805
/h4>- Author: Ben Faber
It's also for apple. And an apple tree acts more like an avocado tree than an alfalfa plant. Perennial woody plants have certain characteristics that are distinct from herbaceous plants. They are all plants, but how you prune, fertilize and irrigate are different. And this course covers fruit trees, which are again different from a pine tree. Zoom in to this multi-day course and learn about fruit tree culture. It is not explicitly on citrus, cherimoya or avocado, but you will gain insights in how to manage subtropical tree crops. And do it from the comfort of your home.
Register for this upcoming course by April 12. More information and registration available at http://fruitandnuteducation.ucdavis.edu/education/principles/
Register for this upcoming course by April 12.
More information and registration available at
http://fruitandnuteducation.ucdavis.edu/education/principles/
/span>- Author: Ben Faber
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.
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.
Source: Citrus Pest & Disease Prevention Program
- Author: Ben Faber
David Haviland, UCCE Farm Advisor discussed integrated pest management for five different species of mites that cause economic damage to citrus, including proper identification, monitoring, and tools for management. Biological control was also be discussed, including the use of predatory mites.
Recording of the February 2021 webinar on Mites in California Citrus by David Haviland is now available on our YouTube playlist - https://youtu.be/pIOe4ZBbYkM
Other recordings in the"Ask the Ag Experts" series from UC IPM are available at:
https://www.youtube.com/playlist?list=PLo3rG4iqv4gHBV3YA6w4wkBufwh7GBjrX
IMAGE: Citrus Red Mite Damage
/span>
- Author: Ben Faber
Paraquat is a very lethal pesticide that requires sime pretty heavy level of protective gear if it is to be used. It's an old pesticide and there are many newer ones that are much safer to use. Here's an example of the power of fungi to neutralize this chemical. Fungi are nature's chemical that shows the power that they have. And we also need to be careful around some of these fungi. They are found to colonize all sorts of things. Penicillium is a common mold on fruit. This one lives in the sea.
Biologically active compounds from the marine fungus Penicillium dimorphosporum protect cells from paraquat, the highly toxic herbicide with no remedy, and might enhance the action of some drugs. The fungus was isolated from soft coral collected in the South China Sea during an expedition on the Akademik Oparin research vessel. Scientists of Far Eastern Federal University (FEFU) and G. B. Elyakov Pacific Institute of Bioorganic Chemistry reported the results in Marine Drugs.
Paraquat a herbicide compound highly toxic for animals and humans. About a hundred countries, including the United States, apply it for crop cultivation and weed control. Dozens of countries, including Russia, have banned the poisonous compound. The problem of paraquat harm to people is widely known in India. Farmers who work in the fields risk dying because of getting a dangerous dose of the substance.
FEFU specialists, together with Russian and foreign colleagues, have found out that compounds from the marine-derived fungus Penicillium dimorphosporum might protect the cells against the effects of paraquat. The experiment was carried out on a neuroblastoma cell line. By origin, these are tumor cells adopted for studying the neuroprotective activity of forthcoming drugs.
"At a very low concentration, about one micromole per liter, the compounds fortified the viability of cells treated with paraquat by almost 40 percent compared to cells treated with paraquat alone. As a further step, we want to clarify the mode of action of these protecting natural molecules. Perhaps they act as antioxidants, and, probably, they can also secure cells from other toxic substances," said Olesya Zhuravleva, Head of the Laboratory of Biologically Active Compounds at the FEFU School of Natural Sciences.
According to the scientist, many active natural compounds have the disadvantage of low production in the host-organism, so their quantity is not enough for the in-depth study.
The case of Penicillium dimorphosporum is no exception. The fungus does not synthesize active compounds galore. However, scientists noticed an interesting feature of the fungus metabolism, which might help to get over this limitation. The point is the sea mold produces a broad range of isomeric compounds, as well as their biogenetic precursor. That means they have the same elements in the composition but differently structured. It looks like a kind of natural crooked mirror, where the set of atoms is reflected many times, and in different ways. That provides the compounds with different functions and the scientists with the chance to modify them. Usually, the synthesis of a large number of isomers is not typical for living organisms.
"In this regard, we plan to scrutinize not the active natural compound itself, but its precursor synthesized by fungus abundantly, which we can modify up to the active state. That would be a successful step because the minor substance is much more difficult to get from a natural source than to adapt one's major inactive precursor. For example, the fungus produces 200 milligrams of an inactive compound that we can customize and as little as six milligrams of an active natural substance. Many medicinal compounds are obtained in a similar semi-synthetic way, which allows avoiding complex and expensive complete synthesis," said Olesya Zhuravleva.
Next, the scientists plan to study in detail the neuroprotective mechanism of the selected active compounds, as well as prospects of using them in a combination with other existing compounds. According to the hypothesis, active molecules of the sea fungus might enhance the effect of some known drugs.
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The study was supported by the grant of the Russian Science Foundation (project 19-74-10014). In the research took part collaborators from Far Eastern Federal University, G.B. Elyakov Pacific Institute of Bioorganic Chemistry (PIBOC FEB RAS), Institute of Chemistry FEB RAS, University Medical Center Hamburg-Eppendorf (Germany), and the Vietnam Academy of Sciences and Technologies (Nhatrang Institute of Technology Research and Application).
Media Contact
Alexander Zverev
zverev.ase@dvfu.ru
84-956-907-816
A delicate Penicillium, although not the one spoken of here. Dr David Ellis, University of Adeliade