California Citrus Mutual president Joel Nelsen has refuted claims in the local California press that South Korea has rejected certain citrus shipments from the golden state.

Local press outlet California Ag Today reported the state's citrus consignments were being rejected in the Asian nation due to sightings of Fuller Rose Beetle (FRB) eggs.

"The Cal Ag article is majorly false. We are trying to straighten that out," Nelsen told www.freshfruitportal.com.

There is only a "heightened concern" in South Korea, according to Dr. Beth Grafton-Cardwell, director of the University of California Agriculture and Natural Resources Lindcove Research and Extension Center.

"Last year, we had extremely warm winter temperatures and the adults laid eggs during the winter, which they don't normally do, and this resulted in lots of infestations," Dr. Grafton-Cardwell said.

"While the beetle's larvae feed on roots of citrus trees, California does not consider it to be a significant enough pest, and their growers do not treat for it."

"Therefore, populations of FRB have built up in most Californian orchards."

South Korea does not currently have FRB, and the country aims to ensure the beetle does not become established.
To keep FRB at bay, Korea traditionally treated all citrus coming from California with methyl bromide fumigation to eliminate any pests that might be on the fruit.

However, years ago the authorities decided they no longer wanted to use methyl bromide for citrus, and asked California citrus growers to develop a new plan to eliminate the pest before the fruit is sent to Korea.

Additionally, a preclearance program was set up with Korean inspectors coming to California to check fruit for FRB so that only loads with undetectable levels of FRB would be shipped to Korea.

Now, to curb the recent anxiety over the growing number of infestations due to the warmer-than-normal winter in California without the use of methyl bromide, growers there are resorting to skirt pruning their trees (FRB is flightless so if the tree is pruned up off the ground it can only climb the trunk to get to the fruit).

They are also using ground and foliar treatments to kill adults so that they don't lay their eggs on the fruit, according to Dr. Grafton-Cardwell.

"The difficulty is that the FRB adults emerge 12 months of the year, and none of the pesticides last very long, so it's hard to kill them all and the Korean tolerance for eggs is very low," she said.

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