RAYMOND, Miss. -- A statewide citrus quarantine was issued recently for Mississippi after one of the most serious citrus plant diseases in the world was detected in the state.

Citrus greening, also known as Huanglongbing or HLB, was confirmed earlier this year, according to a press release from the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service, or USDA APHIS. There is no cure for the disease, which is caused by a bacterial infection spread by the Asian citrus psyllid, a gnat-sized insect. Infected trees die within a few years.

Heeding the quarantine is important to help stop the spread of the disease. Eric Stafne, fruit and nut specialist with the Mississippi State University Extension Service, said people with citrus trees should be vigilant in watching for signs of disease, but there is no need to panic.

“We do not know how widespread the disease is in Mississippi,” Stafne said. “Just because it exists here doesn’t necessarily mean a tree will get it.

“People should be aware of the possible symptoms, but they shouldn’t jump to conclusions about the disease being present in their trees,” he added. “Some of the symptoms of citrus greening, like fruit bitterness, can be caused by other issues. Since we don’t have large acreages of citrus, the chances of widespread infection are less, but not none.”

Officials with USDA APHIS, in cooperation with the Mississippi Department of Agriculture and Commerce, established the quarantine Feb. 20. Under the quarantine, no citrus fruits or plants can be moved in or out of the state without going through the proper USDA protocol.

“APHIS is taking this action because of citrus greening detections in plant tissue samples collected from residential properties in Harrison County,” the release noted. “APHIS is applying safeguarding measures on the interstate movement of regulated articles from the state of Mississippi. This action is necessary to prevent the spread of citrus greening to noninfested areas of the United States.”

Mississippi does have limited commercial production of mostly satsumas along and south of Interstate 10.

“These trees are susceptible, and we could see a decline in the already small industry if these trees were to become infected,” Stafne said.

Symptoms of citrus greening include reduced fruit production and fruit that are bitter, partially green and possibly misshapen. Leaves may have asymmetrical, blotchy mottling, and trees may exhibit twig dieback and drop fruit too soon. Some infected trees will not have any outward symptoms but can still pass the bacteria to other trees.

Adult Asian citrus psyllids are one-eighth of an inch long with either blue-green, gray-brown or orange-yellow abdomens. Their wings are mottled brown, and the last two segments of their antennae are black. They jump or fly when approached.

Nymphs and eggs can be hard to detect. Nymphs excrete a waxy, white substance on plants. The insects lay their yellow-orange, almond-shaped eggs in crevices and leaf folds.

Some species of citrus are more tolerant or resistant to HLB, but satsuma, kumquat, orange, grapefruit, lemon and lime are susceptible, Stafne said.

Items that fall under the quarantine include fruit, trees, branches, green waste and dead trees. Homegrown citrus fruits and plants are also included. Another way to help prevent disease spread is to purchase only USDA-certified citrus plants.

These items can be bought, sold and transported within state lines, but transporting any of these items in or out of state is prohibited.

“The problem with moving quarantined items is that the insect that carries the disease or their eggs may be present. They are small and may not be noticed,” Stafne said. “Taking fruit or trees to new locations can spread the disease since the insects carry it. Once a tree is infected it can act as a reservoir of the disease and lead to more widespread infection. If a tree is confirmed to be infected, it should be removed.”

Citrus greening is found throughout Georgia, Florida, Puerto Rico and the U.S. Virgin Islands. It also has been confirmed in portions of Alabama, California, Louisiana, South Carolina and Texas.

Citrus greening and Asian citrus psyllids are two of five exotic citrus diseases and pests established in the U.S.

For more information about citrus greening and Asian citrus psyllid, visit the USDA APHIS website at https://tinyurl.com/4ek7ddt8.