Research Plant Pathologist
Dr. Barbara J. Smith is a native of south Mississippi and received her B.S. and M.S. degrees in Plant Pathology from Mississippi State University, and her Ph.D. in Plant Pathology from Louisiana State University.
Dr. Smith’s research mission focuses on the epidemiology and control of diseases of blueberries, blackberries, strawberries, and muscadine grapes. Specifically, her objective is to develop environmentally friendly strategies for the control of small fruit diseases based on chemical, biological, and/or cultural control by conducting basic and applied research on the epidemiology, pathogenesis, and genetics of small fruit pathogens and their hosts. Her career with USDA, ARS, began in 1977 at the Small Fruit Research Station, Poplarville, MS (now the Thad Cochran Southern Horticultural Laboratory).
Her strawberry research has dealt primarily with anthracnose diseases caused by Colletotrichum species. She was the first in the U.S. to identify the presence of an important fruit rotting pathogen, C. acutatum, on strawberry and to demonstrate its ability to infect and kill the plant. This pathogen is now recognized as a major cause of fruit rot of fruit and vegetable crops world-wide. She documented important environmental factors required for optimum disease development of anthracnose on strawberry and developed a procedure to efficiently identify anthracnose resistant strawberry germplasm. Currently she is investigating the effect of supplemental lights (LED, UV-B, UV-C, and far UV) on diseases of strawberries grown in protected culture and developing plant screening protocols using non-viable filtrates (presumed toxins) of Colletotrichum species to identify anthracnose resistance in strawberry seedlings.
Dr. Smith has studied major foliar, flower, berry, stem, and root diseases of southern highbush and rabbiteye blueberries. She determined the susceptibility of commercial cultivars to these diseases and developed an assay to identify blueberry germplasm resistant to stem blight. Bacterial leaf scorch was detected in rabbiteye blueberry in Louisiana and three genotypes of the pathogen, Xylella fastidiosa, from rabbiteye blueberry were identified. Her current research is focused on cultural practices and their effect on controlling Phytophthora root rot of blueberries.
On blackberries she has mainly studied the fungal disease, blackberry rosette. She reported that the infection window for this disease extended much longer than previously thought and developed a fungicide spray schedule based on these findings which resulted in higher yields for blackberry growers. Her current research is to develop disease control protocols based on cultural practices of removing rosette infected primocanes, which are a source of fungal inoculum, to reduce rosette disease severity in erect blackberry cultivars.
Dr. Smith identified major berry diseases of muscadine grapes and the susceptibility of major cultivars to these diseases and documented the infection period for the primary fruit rot pathogens. This research showed that six early season fungicide applications were as effective as twelve applications applied over the whole season.
Dr. Smith has had numerous invitations to speak to scientific and grower groups at local, regional, national, and international levels on diseases of small fruit crops and to author chapters on diseases of small fruit crops. She has a total of 106 peer reviewed journal publications and 14 book chapters.