By Jennifer Whitlock
Field Editor
Huanglongbing (HLB), also known as citrus greening disease, is a threat to citrus production around the globe and in the U.S.
In just a decade, citrus greening disease caused a 20.5% decrease in the U.S. fresh citrus market and a 72% decline in orange production for juice and other products.
To help combat the devastating disease, the U.S. Department of Agriculture (USDA) National Institute of Food and Agriculture (NIFA) has invested nearly $11 million in research to universities in California, Florida and Texas.
“NIFA’s Emergency Citrus Disease Research and Extension program brings the nation’s top scientists together with citrus industry representatives to find scientifically sound solutions to combat and prevent HLB at the farm level,” NIFA Director Dr. Carrie Castille said. “This year’s awards represent all three major U.S. citrus growing regions and include possible solutions ranging from blocking HLB transmission from inside the insect vector to utilizing novel anti-microbial peptides to treat HLB-infected trees.”
The five projects funded by NIFA are varied in scope, but all have the same goal: to stop citrus greening and protect the U.S. citrus industry.
In the fiscal year (FY) 2021, Texas A&M AgriLife Research was awarded $7 million. AgriLife proposes to leverage public-private partnerships between the citrus industry, state agencies, universities and USDA’s Agricultural Research Service to roll out advanced testing and commercialization of novel citrus greening therapies.
The state agency has been researching citrus greening diseases since at least 2001, when the Asian citrus psyllid was first found in the Rio Grande Valley of Texas. Citrus greening disease soon followed, with the first official case documented in Texas in January 2012.
AgriLife has since made major jumps in research, with scientists lately using gene-editing technology to accelerate citrus greening-resistant variety development.
The University of Florida was awarded $2.7 million for three projects in FY 2021, while the University of California-Riverside received $1.5 million in funding for one project.
Click here to view the list of funded projects.
Citrus greening, which is caused by an insect bacterium, affects nearly all commercial varieties of citrus. Grapefruit, sweet oranges, mandarins and some tangelos are most susceptible, while sour oranges, trifoliate oranges, lemons and limes are least susceptible.
It is spread when a disease-infected insect, the Asian citrus psyllid, moves from tree to tree feeding on new shoots, according to USDA’s Animal and Plant Health Inspection Service.
Although the resulting tree disease is not harmful to humans, infected trees produce fruit that is green, misshapen and bitter, and therefore unusable for fresh fruit or juicing. Most trees die within a few years of infection.
Because there is currently no cure, farmers must destroy infected groves to control the spread.
More information on citrus greening in Texas is available at citrusalert.com.