SCIENTISTS FROM UCR DISCOVER NEW CITRUS GREENING TREATMENT

Researchers say it’s safer than chemicals

UC Riverside says its scientists have discovered a new treatment for a disease that has affected millions of acres of citrus crops worldwide and continues to threaten crops in California's citrus hot spots, including Riverside County.

Fingertip-sized, mothlike flying insects spread citrus greening disease, also known as Huanglongbing or HLB, which can destroy plants' vascular systems and render fruits misshapen and unsellable, and typically kills infected trees within a few years.

The new treatment is an antimicrobial peptide that kills the bacterium in affected crops. It's a naturally occurring molecule found in wild citrus relatives, but it needs to be applied a few times each year to fend off new insects that can keep reinfecting crops as time goes on.there remains no onetime systemic cure for the disease, although researchers contend the new treatment can be sprayed on healthy crops periodically as a preventive measure.

According to university officials, the new treatment is safer and more cost-effective than other treatments on the market, which typically include antibiotic sprays.

“This peptide is found in the fruit of Australian finger limes, which can naturally tolerate Citrus Greening bacteria and has been consumed for hundreds of years,” said UCR geneticist Hailing Jin, who discovered the treatment following five years of research.

“It is much safer to use this natural plant product on agricultural crops than other synthetic chemicals.”

In August 2017, the Riverside County Board of Supervisors declared a local state of emergency because of the potential spread of the citrus greening disease.

The county's roughly 20,000 acres of commercial citrus crops yield about $187 million annually, and citrus greening disease poses a direct threat, according to agricultural officials.

Asian citrus psyllids, which spread the disease, made their U.S. debut in Florida nearly 20 years ago. The disease rampaged throughout Florida in 2005 and has inflicted an estimated $3 billion damage to crops in the Sunshine State, according to a study published by the University of Florida.

The insects first appeared in California in 2008.