Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


UC Riverside entomologist helps manage invasion threats posed to California's avocados

Avocado seed moth could devastate California’s avocados, warns Mark Hoddle, currently on a field trip in Peru

California's avocado industry is worth more than $320 million annually, and has about 6,000 growers farming more than 6,000 acres of land. Indeed, California grows nearly 95 percent of the country's avocados.

University of California, Riverside entomologist Mark Hoddle is in Peru until the end of July 2010 to look for known avocado pests, in particular, the avocado seed moth, Stenoma catenifer, that could wreak havoc on California's avocados should the pest make its way to the state.

"This pest is native to Peru, and is particularly destructive in avocado-growing areas in the Chanchamayo region of the Junin District – a somewhat warm and humid jungle zone," said Hoddle, the director of the Center for Invasive Species Research, who, like an Indiana Jones of invasive species, travels several times a year to locations around the world in search of invasive pests that could threaten California's agriculture, urban, and wilderness areas.

Hoddle, also a biocontrol specialist in the Department of Entomology, and his research team have collected almost 300 pest-infected avocados from orchards and fruit vendors in Peru, and are rearing out the pests and their natural enemies in their lab. Later, these pests and their biocontrol agents will be identified by taxonomic specialists, and described and named if they turn out to be species new to science.

"As part of the Stenoma survey, we are prospecting also for unknown species of avocado fruit pests – those that have not been recorded attacking avocados before," Hoddle said. "These would be the wild cards in invasion biology because we don't know what they are and we don't know how to look for them, or what their tell-tale damage signatures are. This type of information collected in collaboration with overseas trade partners will help us to more confidently identify risky invasive pests."

When an unknown pest shows up, establishes and causes havoc, oftentimes researchers can be left scrambling for information on how best to develop eradication or management plans.

"We have seen this twice before in California with avocado pests, the persea mite, and the avocado thrips," Hoddle said. "Both were species new to science when they first showed up in the United States, and they are the worst two invasive pests California avocado growers need to manage. The persea mite, which is native to Mexico, has also spread to Costa Rica, Israel, and Spain where it attacks avocados."

Hoddle explained that in the case of Peruvian avocados, which are already being imported into California, he and his team want to be fully prepared for pests that could be invasive in California.

"We want to get ahead of the curve by proactively identifying any new pests, should they exist, and documenting in detail what damage they cause," he said. "We also want to identify any natural enemies they may have and how effective these biocontrol agents are."

The avocado seed moth can attack close relatives of the avocado, such as greenheart, an important timber tree in South America. The pest could possibly attack and survive on California bay laurel, a plant native to California that is closely related to the avocado.

"We have also found some generalist avocado pests in Peru that eat a variety of plants," Hoddle said. "One of these is the well known native bag worm, Oiketicus kirbyi, which can feed on more than a hundred different plants, including eucalyptus!"

Hoddle noted that Peruvian avocados exported to California arrive from export orchards certified by the U.S. Department of Agriculture.

"We have visited some of these orchards during this trip," Hoddle said. "They are impressive in terms of their vast size, the professionalism with which they are managed and the extraordinarily strict entrance procedures which are designed and rigorously enforced to keep pests out."

To monitor Stenoma that could be infecting Peruvian avocados, the Hoddle team deployed pheromone traps in certified avocado export orchards and avocado growing areas not certified for export.

"The sex pheromone is very attractive to adult male Stenoma," Hoddle said. "As expected, Stenoma has not been trapped in export orchards located in the coastal desert production regions of Peru. In non-certified export areas in the Junin District, where Stenoma is known to occur, males have been trapped.

"It is abundantly clear that the sex pheromone we developed for Stenoma cantenifer from our recent research in Guatemala works in Peru," Hoddle said. "We have shown that it also works in Mexico, Guatemala and Brazil. It is likely to work in any country with a native Stenoma population – Mexico, all of Central America and parts of South America. Countries exporting or wanting to export avocados to the United States should use the Stenoma pheromone to monitor their export orchards for this pest to demonstrate that they are pest-free year round."

In California (San Diego, Riverside, Ventura, and San Luis Obispo Counties), Hoddle's team already has set up a proactive monitoring network with the Stenoma pheromone to detect the moth early should it ever arrive in the state and, if need be, eradicate it when populations are still small and highly localized.

For the research project in Peru, Hoddle is partnering with SENASA (Servicio Nacional de Sanidad Agraria), Peru's equivalent of the U.S. Department of Agriculture's Animal Plant Health Inspection Service (USDA-APHIS). SENASA invited Hoddle to Peru to place Stenoma pheromone traps in their export orchards, and provided him with staff and laboratory space to rear out the bugs inside avocados collected from non-certified export areas.

"Without SENASA's assistance, we would never have been able to access the orchards or our study sites," Hoddle said. "SENASA has been a first class and extremely cooperative partner in this avocado pest survey project."

The California Avocado Commission provided financial support for Hoddle's research trip to Peru. Hoddle is accompanied in this research project by Christina Hoddle, his field assistant.

In mid-August, he will travel to India and Pakistan to study the Asian citrus psyllid and its natural enemies, and to potentially develop a biocontrol project for this pest, which poses a serious threat to California's citrus after its successful establishment in San Diego County in August 2008.

The University of California, Riverside ( is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment of about 18,000 is expected to grow to 21,000 students by 2020. The campus is planning a medical school and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Graduate Center. The campus has an annual statewide economic impact of more than $1 billion.

A broadcast studio with fiber cable to the AT&T Hollywood hub is available for live or taped interviews. To learn more, call (951) UCR-NEWS.

Iqbal Pittalwala | EurekAlert!
Further information:

Further reports about: Avocado SENASA Stenoma invasion threats invasive pests sex pheromone

More articles from Agricultural and Forestry Science:

nachricht Forest Management Yields Higher Productivity through Biodiversity
14.10.2016 | Technische Universität München

nachricht Farming with forests
23.09.2016 | University of Illinois College of Agricultural, Consumer and Environmental Sciences (ACES)

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

How nanoscience will improve our health and lives in the coming years

27.10.2016 | Materials Sciences

OU-led team discovers rare, newborn tri-star system using ALMA

27.10.2016 | Physics and Astronomy

'Neighbor maps' reveal the genome's 3-D shape

27.10.2016 | Life Sciences

More VideoLinks >>>