The NOA Summer Convention featured presentations from Brian Nault with Cornell University and Erin Otto with USDA APHIS discussing the Allium leafminer.
Otto reminded attendees that the Allium leafminer is a non-quarantined pest in U.S. ports of entry. Anything with the pest on it can enter the country, except for states with the Federally Recognized State Managed Phytosanitary (FRSMP aka “free-stamp”) program in place. Currently, only California has FRSMP, which means the feds officially recognize the state’s desire to control the pest’s movement and provide assistance at ports of entry.
As of March 2019, Oregon has temporary FRSMP status because the state has informed APHIS’ Plant Protection and Quarantine (PPQ) of its intent to submit a FRSMP petition. If Oregon does not submit a petition by April 2020, the temporary status ends.
If customs officials find Allium leafminer at a California (or Oregon, temporarily) port of entry, there are four options: treatment (if available), re-export to the country of origin, destruction or the shipment can be redirected to another state.
Any state can apply for FRSMP, but it is a complicated and lengthy process. More information can be found at www.aphis.usda.gov/frsmp or by emailing Otto at erin.m.otto@usda.gov.
Nault said that leafminer infestations in onion are really nothing new. The American serpentine leafminer is found throughout all onion areas in North America, and the vegetable leafminer is found in southern states. Both of these pests feed on leaves, so economic loss is typically not much of a problem in onion.
Allium leafminers are larger and lay eggs in leaves. The larvae ultimately migrate down to the base of the plant, leaving entry points in bulbs for bacteria, which can lead to soft rot. The insect is found in Pennsylvania, New York, Massachusetts, New Jersey and Maryland.
The good news, Nault said, is that there has been no economic loss due to Allium leafminer damage in conventional onion bulb fields.
“This insect seems to clearly like leek and scallion a lot more than it does bulb onion,” he said.