- Author: Ben Faber
Loquat is an evergreen tree with delicious fruit. Too bad some varieties have big seeds, but in some countries like Spain and China they are a big deal. At one point, Orange County had 500 acres of trees – ‘Big Jim', ‘Gold Nugget', ‘Victory', ‘Mammoth'….. Now it's more of a pleasurable backyard shade tree that gets immense quantities of fruit twice a year. Too good to be true.
But it may be troubling to hear that a new bark beetle pest of loquats has been identified in China by the University of Florida's Forest Entomology Lab. A new paper describing the beetle has just been published in the journal Insects.
The beetle, newly named Cryphalus eriobotryae, was first observed in April of 2018 in a tree nursery near the city of Suzhou in Jiangsu, a coastal province of China. Loquat trees were dying for unknown reasons. There are no other insect pests known either to specialize in loquat trees or to kill them. But when the problem spread to other areas during the summer of 2018, it became clear that a real problem had emerged.
Chunrong Chu, a technician with Suzhou's forest service, and Sizhu Zheng, an entomologist with Suzhou's customs agency, sent photos and specimens of the beetles to the UF Forest Entomology Lab for identification, led by Dr. Jiri Hulcr. The lab has staked out an unusual specialty in the entomology world. Having already built the world's largest cryo-collection of bark and ambrosia beetles, Hulcr's team established a volunteer service for the global identification of bark and ambrosia beetles.
Dr. Andrew Johnson, a research scientist in the UF Forest Entomology Lab, was studying the genus. He quickly realized that he was looking at an entirely new species. He named the beetle eriobotryae in reference to the name of the genus of plants to which loquats belong. "By giving this a name and recognizing it as a potential threat, we can encourage further work," said Johnson. "Before giving it a name, it is difficult to coordinate and to work on this species."
The work has barely started. The beetles' DNA has recently been sequenced and analyzed via a method that examines one very specific part of a genome in order to determine its identity. But a full pre-invasion assessment has not been conducted. It is still not clear exactly where the beetle came from, what its potential is as an invasive species, or what means can be used to prevent and fight future outbreaks.
Bark beetles are a group of insects including thousands of species that chew holes through the bark of a tree and feed on the phloem just beneath the bark. They live most of their lives invisibly, breeding and rearing their young in tunnels called galleries. Most bark beetles only colonize recently dead trees, but some species may turn their attention to living trees and can kill them, sometimes on a massive scale, as with the Southern pine beetle.
In affected areas of Jiangsu, the threat of the loquat beetle is not an obscure issue. Loquats are as economically and culinarily important as, say, oranges in Florida or avocados in Mexico. "Local people really want to know how to control and kill this pest," says Dr. You Li, a scientist with the UF Forest Entomology Lab who also contributed to the paper. "That's why they are happy we could tell them more about this beetle."
So far, the loquat beetles have all been found in nurseries, which may be a clue to the origins of the beetle and the means of its spread. Transportation of live plants from one location to another is a frequent vector for movement of invasive species that can hitch a ride.
The process of loquat death begins when beetles make tiny holes at the base of the tree. This progresses up along the trunk as the offspring of the initial beetles mature and start tunnels of their own. As the galleries of beetles become more dense, eventually, the tree may be girdled around its circumference. At that point, it is no longer able to move water and nutrients from the roots to the leaves. The leaves rapidly turn brown and die while remaining attached to the branches.
So it looks like we can add another beetle to the list that is causing problems around the world.
Get the low down on bark beetle spread:
Peter H.W. Biedermann et al. Bark Beetle Population Dynamics in the Anthropocene: Challenges and Solutions, Trends in Ecology & Evolution (2019). DOI: 10.1016/j.tree.2019.06.002
Photo: Loquat orchard under netting in Spain:
Read on:
https://www.mdpi.com/2075-4450/10/6/180
Cryphalus eriobotryae sp. nov. (Coleopetera: Curculionide: Scolytinae), a New Insect Pest of Loquat: Eriobotrya japonica in China
(A) Tree killed by Cryphalus eriobotryae; (B) teneral adult; (C) adult outside a newly excavated gallery; (D) larva; (E) pupa; (F) cankers on the trunk; (G) adults made the canker; (H) tree recovered after failed beetle attack; (I) galleries on the underside of peeled bark.
The newly-identified loquat beetle. Credit: Dr. Andrew Johnson
/span>- Author: Ben Faber
Snails and Slugs (May 22, 2019 from 3-4pm)
Presenters: (!) Dr. Cheryl Wilen (UC IPM), (2) Dr. Rory Mc Donnell and (3) Dr. Dee Denver (Oregon State University), (4) Dr. Adler Dillman and (5) Dr. Irma De Ley (UC Riverside). The webinar will cover an overview of snail and slug biology, damage and management with emphasis on brown snail and Italian white snail, and current research on slug biocontrol using nematodes. One DPR CE unit (other) and one CCA CE unit (IPM) are approved.
And What Else Are the
UC Ag Experts
Talking About?
Event Name | Date |
---|---|
UC Ag Experts Talk: Snails and slugs | 5/22/2019 |
Uc Ag Experts Talk: Management of Weeds in Citrus Orchards | 6/19/2019 |
UC Ag Experts Talk: Citrus Dry Root Rot | 7/24/2019 |
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
And Next up is:
Management of Weeds in Citrus Orchards (June 19, 2019 from 3-4pm)
Dr. Travis Bean, assistant weed science specialist in UCCE, will discuss the importance of weed management in citrus, tree age and variety considerations, scouting and weed identification, cultural and mechanical practices, and pre- and post-emergence herbicides. One DPR CE unit (other) and one CCA CE unit (IPM) are pending.
Register in advance for the webinars by clicking on the event links above.
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).
- Author: Beth Grafton-Cardwell
What Are the Ag Experts Talking About?
Event Name | Date |
---|---|
UC Ag Expert talks about citrus thrips | 10/17/2018 |
What is involved in the webinars?
A series of 1 hour webinars 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. These programs are open to all, but are geared to those individuals, such as PCAs and Growers who need CEUs.
Topics: pests and diseases of citrus and avocados
What are the topics and how do I register?
Citrus Thrips - October 17, 2018 at 3 pm
Register in advance for this webinar by clicking on the event link above.
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).
https://ucanr.edu/sites/ucexpertstalk/
Photo: The mighty citrusthrips - Scirtothrips citri
/table>/h1>
- Author: Ben Faber
Citrus: UC IPM Pest Management Guidelines
Publication Number: 3441 Copyright Date: Rev. 2017
Length: 234 pp.
Language: English
Inventory Type: PDF File
|
|
This is a free publication if you access it as a web page or downloadable PDF document.
These official UC-approved guidelines for pest monitoring techniques, pesticide use, and nonpesticide alternatives for agricultural crops are essential tools for anyone making pest management decisions in the field. This 124-page guideline covers citrus fruit. Updated August 2015. A hard copy version of these guidelines can be purchased as Publication 3441P. The PDF version of this publication is best viewed using the free Adobe® Acrobat® Reader. You can download a free copy of the Acrobat Reader from Adobe Systems Incorporated. Some users have experienced problems using Preview with these documents; we recommend using the Adobe® Acrobat® Reader. |
- Author: Ben Faber
Leafminer, sometimes Leaf Miner. It's that time of year. Those little moths come out in the late afternoon and flit about. They lay their eggs and when they hatch the larvae start burrowing through the leaf. The recent heat and also the generally warm summer have set them off. And it is obvious now. The heat has exacerbated the collapse and drying of the leaves and on older trees it looks like trees have been decorated with a sprinkling of light brownish ornaments. It is disturbing. But it's not the end of the world, like …………ACP can be.
Leafminer adults are tiny moths less than 0.12 in long (2 mm) with wings span twice as wide.
Pretty shocking from a distance
Citrus leafminer larvae feed by creating shallow tunnels, referred to as mines, in young leaves. It is most commonly found on citrus (oranges, mandarins, lemons, limes, grapefruit and other varieties) and closely related trees (kumquat and calamondin). The larvae mine the lower or upper surface of the leaves causing them to curl and look distorted. Mature citrus trees (more than 4 years old) generally tolerate leaf damage without any effect on tree growth or fruit yield. Citrus leafminer is likely to cause damage in nurseries and new plantings because the growth of young trees is retarded by leafminer infestations. However, even when infestations of citrus leafminer are heavy on young trees, trees are unlikely to die. But they can sure struggle pushing new leaves that then get attacked anew.
Several years ago, we did a trial where we sprayed mature trees with leafminers every month for 18 months with a rotation of different chemicals and even the most heavily treated trees had some damage on them. The most heavily infested trees looked horrible, but in that period of time there were no lemon yield differences. Young trees treated with a systemic were able to free themselves of infestation. This has been commented on by others, that soil applied systemics on heavier soils can have problems controlling leafminers.
http://ipm.ucanr.edu/PMG/r107303211.html
Photos: Tunnels and the rapidly dried leaf after a heat spell