Skip to main content
ARS Home » Southeast Area » Fort Pierce, Florida » U.S. Horticultural Research Laboratory » Subtropical Plant Pathology Research » Research » Publications at this Location » Publication #360693

Research Project: Mitigating High Consequence Domestic, Exotic, and Emerging Diseases of Fruits, Vegetables, and Ornamentals

Location: Subtropical Plant Pathology Research

Title: Risk-based HLB Surveys extension– optimizing delimiting survey distance

Author
item Gottwald, Timothy
item Luo, Weiqi - North Carolina State University
item Mcroberts, Neil - University Of California, Davis

Submitted to: Citrograph
Publication Type: Popular Publication
Publication Acceptance Date: 3/1/2019
Publication Date: 3/1/2019
Citation: Gottwald, T.R., Luo, W., Mcroberts, N. 2019. Risk-based HLB Surveys extension– optimizing delimiting survey distance. Citrograph. 10(2):30-32.

Interpretive Summary: A risk-based survey method was developed in 2013 to search California residential areas for citrus huanlongbing, a devastating disease of citrus. Sins the discovery of the disease in 2012 the method has been used to conduct one to three cycles or sweeps of survey throughout the southern California area yearly. To date the method has uncovered ~900 infected trees in the Los Angeles Basin for eradication in an attempt to slow the spread of the disease in California. Each year the results for the prior year survey are statistically analyzed and the survey is 'tweaked' to optimize detection the following year. The risk-based survey captures the current HLB situation, identifies high risk areas, predicts where the disease will occur, and directs surveyors to these areas to more efficiently search for the disease. Such early searches aid state and federal regulatory agencies and the California citrus industry to accomplish disease mitigation and management when the disease is at low incidence, thereby suppressing a severe impending epidemic.

Technical Abstract: Evidence from citrus-producing areas worldwide clearly demonstrates that huanglongbing (HLB) is not a disease that can be managed effectively by individual growers. Rather, it is a disease that must be managed simultaneously by regulatory agencies and the whole production industry. The importance of an effective early HLB detection system for California is increased by the existence of the large and diverse commercial citrus industry, whose landscape is intermixed with an extensive residential citrus population. Since 2013, we have developed and continuously refined a risk-based survey that addresses the urgent need to respond to the HLB threat. Rather than waiting for the disease to appear locally the survey anticipates pathogen introduction and spread statewide. The risk-based survey captures the current HLB situation, identifies high risk areas, predicts where the disease will occur, and directs surveyors to these areas to more efficiently search for the disease. Such early searches aid disease mitigation and management when the disease is at low incidence, thereby suppressing a severe impending epidemic.