Citrus Research Meeting Focuses on Moving Plant Material

Industry Discusses Strategies in Fighting  Huanglongbing Disease

By Jessica Theisman, Associated Editor

Franco Bernardi, the interim president of the California Citrus Research Board based in Visalia, attended a recent citrus regulatory meeting in Denver, Colorado. He has sat on that board for 27 years and is helping out while a new president is searched for and named.

The CRB just turned 50 years old, and it is all about finding solutions to the trying issues of pests and diseases in California citrus. Bernardi said the meeting was comprehensive in regard to moving plant material between research labs around the country.California citrus

“It was a very good meeting and fortunately it had the right people in the room, which doesn’t always happen when you have a large meeting like that,” Bernardi said.

It is a very complicated subject, but with the regulators, researchers and plant breeders, it was a good meeting. These decisions are leading to allow genetic material to be moved from one state to the other.

A lot of this surrounds huanglongbing (HLB) genetic material which is causing concern, but Bernardi said there was a consensus on how to do it.

“The regulators are now going to have to put some teeth in the regulation,” he said.

Some regulations may even need to be changed. Many states have the same safeguards. One thing that came out of the meeting is some of these processes and protections of moving material from one place to the other are already in place.

No End in Sight for Stopping Huanglongbing Disease

Millions Spent to Fight Huanglongbing, with No Cure

By Mikenzi Meyers, Associate Editor

The California citrus industry—made up of 3,500 growers in Ventura, Riverside, and the San Joaquin Valley, and encompassing 70-75 packing houses—is an agricultural facet that continues to make California a fresh citrus powerhouse. Joel Nelsen, President and CEO of the California Citrus Mutual, spoke to California Ag Today recently on the industry-wide issue of Huanglongbing Disease—a deadly disease that has threatened the industry in every part of the state.

“For our industry, it’s a combination of enthusiasm, unity, frustration, and aggravation because we continue to fight the spread of the disease in Southern California.”

“We’re continually frustrated because science has not yet found a cure. We’ve given the scientific community an average of thirty to forty million dollars a year to find a cure for this disease.”

In a recent study done by the University of California, Riverside, economic outputs of the citrus industry is roughly $7 billion.

“It’s an economic engine for certain parts of this state. Lose it, and it’s not a positive alternative, that’s for sure,” Nelsen said.

IR-4 Program Trying to Help Florida Citrus Industry Due to HLB

IR-4 Researchers Control Material to Help Citrus Industy

By Patrick Cavanaugh, Editor

Jerry Barron, executive director of the IR-4 Project at Rutgers University in New Jersey spoke to California Ag Today recently about his program.

A major priority with the IR-4 Project is the prioritization of projects that need to be done to find crop protection products for crops such as citrus. Among the urgent challenges for citrus is the control of the Asian Citrus Psyllid (ACP) which vectors Huanglongbing (HLB)—a fatal disease to citrus. Barron spoke about the disease, which has devastated Florida citrus growers and all parts of the citrus economy in the state.

“HLB is devastating Florida citrus growers and the economy in Florida. It’s about a billion dollars of lost production, which is affecting local communities, food processors, and the people who are harvesting the fruit,” Barron said. “It is totally disrupting the whole economic base of certain areas.”

Asian Citrus Psyllid Yellow Trap (Source: Citrus Pest & Disease Prevention Program)

“So what we’re trying to do is work with the people in Florida, to provide them some tools, not only to control the Psyllid which transmits the disease but also provide them some tools to help control the disease once it’s infected the plant.

“At this point, it’s very difficult because certain crop protection products are just not available, but we’re trying to find these magic bullets to truly give them a solution for this devastating problem,” he said.

Fighting Asian Citrus Psyllid On and Off the Farm

Fighting ACP on Farms and Residential Areas Critical

By Hannah Young, Associate Editor

Pests and diseases are as prominent as ever not only for California farmers but in residential areas as well. California Ag Today recently spoke with Rick Westcott, a senior sales rep for Bayer Crop Science, about preventative materials for pests and diseases and the importance of controlling the spread of those diseases, particularly Asian citrus psyllid.

Westcott explained that the advantage of Movento, a powerful insecticide, is that it is systemic, it’s applied early, and it will translocate throughout the entire tree.

“It’s both phloem and xylem movement, so it’ll go down into the roots and then back up so it constantly recirculates within the plant,” Westcott said. “That’s what gives it the longevity of control.”

In citrus trees, Movento typically takes about 65 to 70 days to start working after circulating through the plant which helps with the longevity of the product, Westcott added.

Although Movento is not used specifically for Asian citrus psyllid, it has proved to aid in controlling the pest.

Westcott said Movento is currently being used against citrus red scale and applied during pedal fall along with thrip sprays, which farmers are applying anyway.

“It will take care of your red scale, your early red scale spray, and of course, because it also controls Asian citrus psyllid, it’s a bonus to do that too,” Westcott said. “Then the other thing that they’re doing with the thrip spray as well for katydid control, which is also an issue in citrus at that thrip timing.”

By patrolling and monitoring for ACP, the spread of HLB can also be controlled.

“The key is to keep the ACP at the lowest level possible or zero if that’s possible. [The] fortunate thing for us in the San Joaquin Valley is the fact that we do a lot of spraying for other pests throughout the year that almost everything that we put in the tank happens to also control ACP at the same time,” Westcott explained.

Westcott said that this is the reason we have not seen a huge outbreak of ACP in the San Joaquin Valley, unlike other parts of California.

“The problem isn’t in any commercial grove at this point, but it’s all residential,” Westcott continued. “It’s all concentrated in the residential areas, so there are certain products that you can use an ag that you can’t use there, but most of them, fortunately, you know, they have a label for both residential and agriculture, so they do crossover to stop them there so they don’t get here.”

HLB is still posing a threat in California, but most specifically in the Los Angeles area.

“The total amount of trees currently that are infective with HLB in the counties of LA, Orange and Riverside County is 645. And then if you compare that from a year ago: a year ago, there were only 73 trees that they had infected, and it’s changing every day,” Westcott said.

Governor Brown Includes $12.5 Million In Budget for HLB Control

HLB Funds To Be Used by the Citrus Pest and Disease Prevention Program

News Release

Recognizing the importance of protecting California’s commercial citrus industry and backyard citrus trees, Governor Jerry Brown’s 2018-19 California state budget includes $12.5 million from the general fund dedicated to fighting an incurable citrus disease called Huanglongbing (HLB).

Signed last week, the funds will be used by the Citrus Pest & Disease Prevention Program (CPDPP), a program primarily funded by California citrus growers and administered by the California Department of Food and Agriculture. The CPDPP helps detect and eradicate Huanglongbing in residential areas, suppress Asian citrus psyllid populations, control the movement of the Asian citrus psyllid, enforce regulations, and fund outreach programs to homeowners, industry members and local governments.

While Governor Brown’s commitment to helping fight HLB is a step in the right direction, California citrus is at a crossroads. More than 685 cases of Huanglongbing have been detected in California, with more than 350 detections in 2018 alone, all in urban areas of Los Angeles, Orange and Riverside counties.

Research Nets Going Over Citrus Trees To Prevent Huanglongbing Disease

Blocking Psyllids Carrying Disease is Key

By Jessica Theisman, Associate Editor

Beth Grafton-Cardwell is the director of the Lindcove Research Extension Center in Tulare County and research entomologist based out of the University of California, Riverside. She recently told California Ag Today that there is work being done on installing a net structure to protect trees from Asian Citrus Psyllids, which spread the deadly Huanglongbing disease. Texas A&M researchers are installing net structures on the edge of groves to block psyllids from coming into an orchard.

Psyllids have a preference for borders. These nets could have yellow sticky strips of material with an insecticide on it, so there would be an attract and kill process.

Beth Grafton-Cardwell

Other research is looking at netted structures that will completely enclose the citrus trees.

“Researchers are going to construct a completely enclosed net structure to grow the citrus trees in a block at Lindcove,” Grafton-Cardwell said. “We will study how well one can grow citrus under the screen so there could be the ultimate protection against pests and diseases.”

“The mother trees and increased trees have to be grown under the screen, but the field trees do not necessarily have to be,” she said.

Cold temperatures in the winter to protect the citrus from the psyllid.

“The cold temperatures hardened off the tissue, which makes it hard for the psyllid to find any place to lay eggs, and they probably cost some mortality to the psyllid,” Grafton-Cardwell explained.

Most outbreaks are in Southern California. Los Angeles, Orange County, and a few trees in Riverside.

“Prevention is working and there are fewer outbreaks in the Central Valley,” Grafton-Cardwell said.

Dr. Mark Hoddle and Dr. Kelsey Schall (both from UC Riverside) have been monitoring backyard situations. They are researching the release of beneficials such Tamarixia and other generalist predators like Syrphid flies.

“They have been reducing psyllids by about 70 percent in the backyards, and that’s really good news,” Grafton-Cardwell said.

Citrus Psyllid Control Strategy Changes

Reducing Sprays in Areas, and Border Nets

By Jessica Theisman, Associate Editor
beth_grafton-cardwell
Entomologist Beth Grafton-Cardwell

Huanglongbing, vectored by the Asian Citrus Psyllid, (ACP) is the dreaded disease that has nearly wiped out the Florida citrus industry and is a potential problem for citrus growers in California. California Ag Today recently met with Beth Grafton-Cardwell, a UC Cooperative Extension Specialist. She specializes in integrated pest management; she discussed new strategies for the control of HLB.

“We have been surveying grower orchards in southern California and following how pesticide sprays are working, and I’m going to make some new recommendations on how to handle the populations down there,” said Grafton-Cardwell, who is also the director of the Lindcove Research and Extension Center. “Some regions of Southern California are easier to control psyllids than others. The pesticide treatment is less intensive due to the desert climate. San Diego is one of the areas that is less intensive due to the drier trees making them more hardened off, with less new flushes, where ACP is attracted.”

“There are other areas of southern California where the trees flush continually, providing great places for the psyllids to lay eggs, and that is where treatments are going to have to intensify,” she explained.

Areas such as Ventura, Riverside, and San Bernardino have to increase their treatments in the fall for better control.

And researchers are currently studying new prevention and control methods.

“Texas A & M has been looking at erecting net-like borders around the orchards because the psyllid tends to go to the edges,” Grafton-Cardwell said.

They want to treat the netting with yellow strips of sticky paper that would attract and/or apply insecticides to kill the psyllid.

“Our research is showing that often the infestation starts on the borders. Growers may have to intensify the number of treatments, but they don’t have to treat the entire orchard,” Grafton-Cardwell said. “Growers might be able to fight the psyllid with only treating the trees on the outer edges.”

Relentless Search for ACP and HLB Trees

Intense Inspections of Urban Citrus Trees Continue

By Patrick Cavanaugh, Editor

Joel Nelsen is president and CEO of California Citrus Mutual, based in Exeter. He told California Ag Today recently that there is an “active plan to look for trees harboring Asian Citrus Psyllids (ACP) infected Huanglongbing (HLB) trees in urban areas because we’re looking for nobody else across this country, let alone in the southern hemisphere, to look for infected trees in the urban area. Mexico and Brazil didn’t do it. We’re doing it.”

Huanglongbing
Joel Nelsen

The hope is that they find HLB and stop it there.

“Commercial growers are under tight testing programs to combat the Asian Citrus Psyllid. As far as it relates to commercial growers, we’re doing enough trapping that we’re not finding what we call hot spots of Asian Citrus Psyllids,” Nelsen said. “Secondarily and most importantly, we have a very strict clonal protection program, so growers are only allowed to access trees after they’ve gone through a rigorous testing program at both the nursery and the rootstock from the university.”

Nelsen said that the chances of a grower introducing the insect into an area is rather slim; it’s more often likely that the disease will be introduced to a grove.

Testing is random and more lab space is needed.

“Most of it’s been random because it is an intensive program. We’re analyzing roughly 20,000 leaves and twigs every month,” Nelsen explained. “We’re analyzing several thousand ACP every month. In fact, our lab capacity is capped, and one of the discussions that we’re having is to identify what labs can do what and whether or not we need to expand the number of labs doing business.”

“So we are looking at additional lab space, and in fact, we have already contracted with the University of Arizona Lab in Tucson  and maybe we’ll consider using private labs to do the initial work,” Nelsen said. “Now, they’re not going to be able to confirm whether or not an ACP is there, but they go in and evaluate that twig or green waste waste and if in fact there is a suspicion, then you send in the California Department of Food and Agriculture folks.”

More Cooperation Regarding Citrus Health and HLB Disease

Citrus Health Response Program Discussed at UC Riverside

By Patrick Cavanaugh, Editor

California Ag Today recently interviewed Joel Nelsen, president and CEO of the California Citrus Mutual. He spoke on his recent trip to UC Riverside about the Citrus Health Response Program. While speaking with USDA, they discussed the game plans that will be used to battle Huanglongbing (HLB) disease, which is vectored by an invasive insect called Asian Citrus Psyllid.

“We got into it, which I thought was an interesting discussion. What would growers do if in fact HLB was discovered in a grower’s orchard and what would the be obligated to do,” Nelsen said.

“And what came out of that discussion is that we are going to work with the USDA. We’re going to develop a war game scenario. We’re going to bring people into a room and start talking about it, just to see what the reactions were, and we’re going to challenge these individuals to do what needs to be done,” Nelsen explained. “We’re just going to have to figure out how best to address the industry and areas like this.”

Nelsen said that they discussed whether or not there was enough being done in that partnership with the homeowner. “We came to the conclusion that no, quite frankly the industry has been carrying that ball and that USDA and CDFA can do a little bit more in their role as government”

Tree removal and beneficial insects were also discussed.

“We talked about the continued trees being removed, and everybody was satisfied about that. We talked about whether or not beneficial insects can help in this situation. Surprisingly, the answer was pretty much no,” Nelsen explained. “Beneficial releases may help in an urban environment to a small extent, but from a commercial standpoint, it doesn’t help. So there were a lot of discussions, some debate, and most of all, some camaraderie that was developed as far as going forward.”

Nearly 400 trees in front and back yards of homes have been destroyed due to testing positive to HLB disease.

“They’re all in a clearly defined geographical area in Southern California,” Nelsen said. “So what we have is a lot of backyard adventures that bring in rootstock that unfortunately was diseased, and as a result of that, those individuals are the ones that are seeing problems associated with their own trees.”

Fighting Huanglongbing Is Job One

Citrus Health Program Protecting State’s Industry

By Patrick Cavanaugh, Farm News Director

Joel Nelsen, president and CEO of the California Citrus Mutual based in Exeter, spoke to California Ag Today about a recent trip to UC Riverside to discuss the Citrus Health Response Program and huanglongbing disease.

“For the last several years, the federal government and the California citrus industry had a wonderful partnership with some ideas, some regulation, and most importantly, with some funds,” Nelsen said. “So periodically, USDA comes to do an audit as to what we’re doing, how we’re doing it, and whether or not there needs to be some reevaluation.”

“The Citrus Health Response Program is the program we call a CHRP for a two-day evaluation. You had scientists and regulators from USDA; you had regulators from CDFA, along with a few scientists,” Nelsen explained.

“You had that entire stakeholder group and members from the scientific community and UC Riverside to evaluate what we’re doing and why, but eventually we did achieve one objective and that’s coming up with several action steps that we need to do as an industry in partnership with government,” he said.

The concern of Huanglongbing disease was discussed and game plans were presented.

“What was interesting is this was a friendly audit. They weren’t interested in taking money away, they weren’t interested in determining if we’re using dollars appropriately, but they wanted us to talk about why we were still spraying in the urban environment for the Asian Citrus Psyllid, which vectors Huanglongbing,” Nelsen said.

“They wanted us to talk about whether or not growers were doing what they were supposed to be doing and of course, they are doing what they need to do to keep the deadly disease out of commercial citrus orchards,” Nelsen said.