Proactive avocado pest control

California’s avocado industry is worth more than $320 million annually, and has 6,000 growers farming 6,000 acres. Indeed, California grows nearly 95% of the country’s avocados. University of California, Riverside, entomologist Mark Hoddle is in Peru 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.

Key Points

• Avocado seed moth could devastate California’s avocados.

• Mark Hoddle’s team has collected 300 pest-infected avocados in Peru.

• Hoddle is rearing out the pests and their natural enemies in their lab.

“This pest is native to Peru, and is particularly destructive in avocado-growing areas in the Chanchamayo region of the Junin District,” says Hoddle, the director of the Center for Invasive Species Research. Like an Indiana Jones of invasive species, he travels around the world in search of invasive pests that could threaten California’s agriculture. Hoddle and his research team have collected almost 300 pest-infected avocados from orchards and fruit vendors in Peru, and are rearing the pests and their natural enemies in their lab for study. 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.

It’s happened before “As part of the survey, we are prospecting for unknown species of avocado fruit pests — those that have not been recorded attacking avocados before,” Hoddle says. When an unknown pest shows up, establishes itself and causes havoc, oftentimes researchers can be left scrambling 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 says. “Both were species new to science when they first showed up in the U.S., 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.”

In the case of Peruvian avocados, which are already imported into California, he and his team want to be fully prepared for pests that could be invasive in California. “We also want to identify any natural enemies they may have and how effective these biocontrol agents are,” Hoddle says.

In 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.

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INVASIVE SHOPPING: Mark Hoddle looks for pest-infested avocados in a fruit stall in San Ramon, Junin, Peru. Fruits with feeding insects inside were collected and returned to the SENASA (Peru’s equivalent to the USDA Animal Plant Health Inspection Service) lab in San Ramon and held in cages to rear new insects for study.

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ACCIDENTS HAPPEN: Stenoma catenifer is an extremely destructive insect and an invasion threat to California, because larvae may be accidentally introduced inside of imported avocados that originate from countries where this pest is a native.

This article published in the August, 2010 edition of CALIFORNIA FARMER.

All rights reserved. Copyright Farm Progress Cos. 2010.