​​​​Risk-Based Residential HLB/ACP Survey for California, Texas, and Arizona​

October 2013 | 47 min., 05 sec.
by Tim R. Gottwald


​This presentation will help consultants, growers, regulators and other practitioners in the Florida, Texas, California and Arizona citrus growing regions to understand and employ a risk based urban survey for early detection of Citrus Huanglongbing (HLB). HLB is a devastating citrus disease threatening many citrus industries and growing regions worldwide. The capacity for HLB to increase very rapidly highlights the importance of early detection and response when dealing with exotic and invasive diseases; developing a detection protocol for HLB for California, Texas and Arizona is the primary objective of this research. The importance of an effective detection system for HLB is underlined by the existence of the large urban citrus population with no disease or vector control that exists as a mixed landscape with commercial citrus production and which poses a continual treat of vector and disease immigration. By the end of the presentation, concerned stakeholders will understand the underlying survey model and risk factors utilized to develop an overall risk algorithm that is used to maximize targeting of manpower and resources and optimize disease/vector detection and response.

About the Presenter

Tim R. GottwaldTim R. Gottwald received his BS in Botany from Long Beach State University in California, in 1975 and his PhD in Plant Pathology from Oregon State University in 1979. He joined the USDA-ARS as a Research Plant Pathologist/Epidemiologist in 1979. Dr. Gottwald was stationed in Byron, Georgia, until 1984, when he moved to the ARS U.S. Horticultural Research Laboratory (USHRL) in Orlando, Florida, to address the 1984 outbreak of citrus canker. Dr. Gottwald relocated with the USHRL when it moved to Fort Pierce in 2000, where he has served as the Research Leader of Plant Pathology for the last 13 years. He has also been an adjunct Full Professor in the Department of Plant Pathology, University of Florida, Gainesville since 1984. Dr. Gottwald is continually consulted on epidemiology and sampling designs on a wide range of pathogens and pests by state, national, and international regulatory agencies and institutions. His research focuses on phytopathology and epidemiology to provide fundamental knowledge on exotic and domestic bacterial, viral, and fungal pathogens. His long-term research goal is to develop innovative disease control/mitigation and sampling strategies based on biological and epidemiological evaluation of disease pathosystems.

Contact Information:
Email: Tim.Gottwald@ARS.USDA.GOV


In 2020, Grow webcasts had more than 110,000 views. Help support our mission to provide comprehensive high-quality, science-based resources to and for plant health researchers and practitioners at no cost.

PDMR submission guidelines and schedule information are available online.


Plant Health Progress is a peer-reviewed multidiciplinary, online journal of applied plant health.