Huanglongbing Disease in Citrus is Top Problem

By Patrick Cavanaugh Farm News Director

Gary Schulz, President of the Citrus Research Board in Visalia, said the pest pressure in citrus comes down to three problems.

“You know, there’s three really. There’s Huanglongbing, Huanglongbing, and Huanglongbing, (HLB)” Schulz said at the recent California Citrus Conference in Visalia. “When I moved to California in 1990, I had an old-timer that was on my board. He said, ‘You know, in California, we have three major challenges: water, water, and water.’ Well, in the citrus research for pests and diseases, it’s really Huanglongbing.”

Gary Schulz

“If we’re talking about red scale or Phytophthora or lemon fruit drop, those are important challenges, but if HLB begins infecting our commercial groves and spreads as rapidly as it can without our attention and treatment or tree removal, the rest are moot,” Schulz said.

He discussed his hope for the future of the California citrus industry.

“I hope that in five years, we’ve solved HLB. That’s my personal goal. Somebody’s got to put the stake in the ground and put a date out there,” he noted.

Schulz said that Citrus Research Board has got a number of research programs that are all working side by side to find that solution, turn that key, and make that happen.

“It may be more than just one solution. We have a researcher at Washington State University in Pullman for example. They’ve earned a research grant from the USDA because of the creativity in putting their work team together and the fact that they bring a whole new fresh approach and fresh thought process to how to culture the bacteria that causes HLB disease. That’s huge in the science community and has never been done before,” Schulz said.

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