The Vertebrate Pest Council is hosting a seminar series this year in conjunction with new partner Target Specialty Products. Don't miss this unique opportunity to learn about wildlife management of a number of bird and mammalian species from staff at the University of California, California Department of Fish and Wildlife, California Department of Food and Agriculture, the Department of Pesticide Regulation and more!
Both structural and DPR continuing education units are available and Vector CEUs have been approved for some venues. For more information on these workshops including speakers, costs, directions, and registration, please see www.vpconference.org.
Next up on Ag Experts Talking is Laurel Wilt Disease which is causing major damage in the native tree populations of the south east United States and the avocado groves in particular. Learn what is being done there and what the potential threat is to California avocados.
What Are the UC Ag Experts Talking About?
What is involved in the webinars?
A series of 1 hour webinars, designed for growers and Pest Control Advisors, will highlight various pest management and horticultural topics for citrus and avocados. During each session, a UC Expert on the subject will make a presentation and entertain write-in questions via chat during and/or after the presentation. As we develop this program, we may expand to other crops.
Topics: pests and diseases of citrus, avocado and other crops
What are the topics and how do I register?
Laurel Wilt (March 20, 2019 from 3-4 pm)
Dr. Monique J. Rivera will present current knowledge of the laurel wilt, the biology and ecology of its vector - Ambrosia beetles, current known location of the disease in the US, Identifying the disease, and the laurel wilt disease prevention in California.Dr. Monique J. Rivera will present current knowledge of the laurel wilt, its biology and spreading. One DPR CE unit (other) and one CCA CE unit (IPM) are pending.
Management of Glyphosate-Resistant Weeds in Orchard Crops (April 24, 2019 from 3-4pm)
Dr. Brad Hanson, cooperative extension specialist, will discuss what is herbicide resistance, current state of resistant weeds in CA permanent crops, identification and lifecycle of key glyphosate-resistant weeds, selection pressure for resistant biotypes and species, herbicide modes of action, and examples of herbicide programs for orchard crops. One DPR CE unit (other) and one CCA CE unit (IPM) are pending.
Are there Continuing Education units?
When the subject discusses pest or disease management, continuing education units will be requested from DPR (1 unit per session). Participants will pre-register, participate in the webinar and be awarded the unit. The sessions will be recorded and hosted on this web site for future study. However, continuing education units will be awarded only to the participants who attend the live version of the webinar.
Who is involved?
This webinar series is brought to you by Ben Faber (UC ANR Ventura Advisor) and Dr. Beth Grafton-Cardwell (Depart of Entomology UC Riverside Extension Specialist) with the technical support of Petr Kosina (UC IPM Contect Development Supervisor) and Cheryl Reynolds (UC IPM Interactive Learning Developer).
Sometimes we don't see things that are not uncommon, but suddenly catch our eye. A recent lemon harvest of a trial in the Central Valley turned up lots of fruit with enlarged nipples on the stylar end. These are from a 'Limoneira 8A' rootstock trial. Not all of of the fruit was like this, but all of the rootstocks had these fruit, so it wasn't a rootstock effect.
On asking around it turns out, this happens in other places, for example on Spanish fruit:
And on Australian fruit:
And even in many normal years and orchards there is some of this special fruit
During the 2018 spring bloom there were several heat waves that hit citrus growing areas. Dr. Mary Lu Arpaia, UCR Fruit Specialist, surmises that high temperatures make for elongated fruit and quite likely impact cell division at the stylar end, as well. So the more heat spells during bloom, it's likely that we will see more of this fruit shape. It's still good to eat.
So a question comes in about a problem with a backyard avocado tree. And it would seem the first question would be about the overgrowth happening at the base of the trunk. This a ‘Fuerte' avocado that is grafted on a seedling avocado rootstock. It's not unusual to see an overgrowth, but this is the most extreme example I have ever seen. So it's basically an incompatibility between the graft and the rootstock. In many cases this is no big problem and trees can live a long time, as this tree has.
But the homeowner wasn't asking about the unusual growth at the base, but the canker that had appeared in the center of the trunk near the base.
This has the classic white sugar exudate that occurs with a wound of any kind in avocado. The sugary sap that contains the unusual mannoheptulose 7-carbon sugar characteristic of the laurel family to which avocado belongs will ooze out of the wound and result in a white crust (Read more about this sugar at: https://www.sciencedirect.com/science/article/pii/S0254629911001372 ).
Anyway, so this backyard tree is in an area that is getting 10 minutes of lawn watering a day. Lawns and avocados don't get along. And avocados don't get along with short, shallow irrigation that result in salt accumulating in the root zone. Which is what has happened here. Salt stress and the result is an infection of bacterial canker (https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=7920 ).
It's not fatal in an old tree like this, but it can predispose the tree to root rot. And that's not something that is easy to treat in backyard settings.
A recent article from the Journal of Agricultural Education explorers how group decisions are often made.
CHAMPAIGN, Ill. -- A tiny insect, no bigger than the head of a pin, is threatening to topple the multibillion-dollar citrus industry in the U.S. by infecting millions of acres of orchards with an incurable bacterium called citrus greening disease.
The battle to save the citrus industry is pitting crop producers and a team of agriculture researchers - including agricultural communications professor Taylor K. Ruth of the University of Illinois - against a formidable brown bug, the Asian citrus psyllid, which spreads the disease.
Trees infected with the disease, also called Huanglongbing or HB, bear small, misshapen, bitter-tasting green fruit and often die within five years. Currently, there's no known cure for the disease, which has cost the U.S. citrus industry billions of dollars in crop production and thousands of jobs since it was first identified in Florida in 2005, according to agriculture experts.
Among other solutions, scientists are exploring the possibility of breeding genetically modified trees that are resistant to the disease.
But given the controversy over the safety of genetically modified food, scientists need to know whether producers will adopt this technology and whether shoppers will buy and consume GM citrus fruit.
A recent study, funded by the U.S. Department of Agriculture, provides some encouraging answers.
Ruth was on a team of scientists from several universities that surveyed a representative sample of U.S. consumers and conducted focus groups to better understand American consumers' attitudes about GM food and agriculture.
About half of the 1,050 people who responded to the survey had positive attitudes toward GM science, the researchers found. Nearly 37 percent of the consumers surveyed felt neutral about GM science and 14 percent had negative perceptions of it.
Most of the people who were receptive to GM science were white males who were millennials or younger, the data indicated. They were highly educated - most held a bachelor's degree or higher - and affluent, with annual incomes of $75,000 or greater.
Women, on the other hand, constituted 64 percent of the group with negative feelings about GM science. Baby boomers and older adults were nearly twice as likely to fall into this group. People in this group also were less educated - about half reported some college but no degree.
The findings were published recently in the journal Science Communication. Co-authors of the paper were Joy N. Rumble, of Ohio State University; Alexa J. Lamm, of the University of Georgia; Traci Irani, of the University of Florida; and Jason D. Ellis, of Kansas State University.
Since social contexts influence public opinion on contentious issues, the survey also assessed respondents' willingness to share their opinions about GM science, their current perceptions of others' views on the topic and what they expected public opinion about it to be in the future.
The research team was particularly interested in exploring the potential impact of the "spiral of silence" theory, a hypothesis on public opinion formation that states in part that people who are highly vocal about their opinions in public encourage others with similar views to speak out while effectively silencing those who hold opposite views.
"If people believe the majority of others disagree with them on a topic, they will feel pressure to conform to the majority opinion," Ruth said.
"People aren't going to be supportive of something if nobody else is supportive of it - no one wants to feel like they are different from the group. That's the reality of the world that we live in today."
By contrast, people surveyed who rejected GM science were more likely to express their opinion when they believed others held the opposite view. But people with positive feelings about GM technology were less likely to speak out when they believed others supported it too.
"The way others express their attitude has an indirect effect on what our attitude ends up being," Ruth said. "We might fall in the actual majority opinion about some of these complex topics, but if other people aren't vocalizing their opinions, we don't know that others out there are like-minded.
"Then we start to think 'Well, maybe I should realign my attitude to what I'm seeing in the media.' What we see in the media is just reflective of the most dominant voice in the conversation, not necessarily the majority opinion. And I think sometimes people don't quite understand that."
Like climate change, GM science is among the complex challenges that some researchers call "wicked issues" - societal problems that are often poorly understood and fraught with conflict, even when the public is provided with relevant science and facts, Ruth, Rumble, Lamm and Ellis wrote in a related study.
That paper was published recently in the Journal of Agricultural Education.
"We must have these conversations about these wicked issues," Ruth said. "If scientists let other people who don't have a scientific background fill the void, we're not going to be a part of that conversation and help people make decisions based upon all of the facts."
To reach Taylor Ruth, call 217-300-6442; email email@example.com