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Raymond G. Grogan Student Travel Grant

Colleagues and friends established this grant in honor of Dr. Raymond G. Grogan for the contributions he made to the science of plant pathology through his research, teaching, and service.


Raymond G. Grogan

Raymond G. Grogan (1920-2016), professor of plant pathology at the University of California, Davis, was born in Emma, GA, and educated at the North Georgia College of Dahlonega and the University of Georgia at Athens, where he earned B.S. and M.Sc. degrees. After a three-year stint in the Navy, he went to the University of Wisconsin to obtain a Ph.D. degree under J. C. Walker in 1948.

He began his career at the University of California, Davis, in 1948, was promoted to professor by 1960, and served as department chair from 1969 to 1974. Professor Grogan taught courses on advanced plant pathology and diseases of vegetable and field crops and guided 23 Ph.D. degree and several M.S. students.

In 1987, Dr. Grogan was awarded the Award of Distinction by The American Phytopathological Society. The Award of Distinction formally recognizes exceptional productivity in research, inspiring leadership, and effective application of plant pathology for the benefit of humanity. This rarely-bestowed honor has been presented only 10 times in the history of the society; Dr. Grogan was the seventh recipient.

Dr. Grogan served the profession as president of the APS Pacific Division, chaired the Committee on Editorial Policy for Phytopathology, and served as APS representative to AAAS and other committees. He served on editorial boards of Phytopathology, Plant Disease, Virology, and the Annual Review of Phytopathology. Dr. Grogan was awarded a National Science Foundation Post-Doctoral Fellowship in 1958 and the Campbell Award for Vegetable Research in 1962, was named fellow of APS in 1969, and was included in Who’s Who in America in 1974.

His innovative, diverse, and creative research included foliar and soilborne diseases of vegetable crops caused by viruses, bacteria, fungi, and abiotic factors. Under J. C. Walker’s tutelage, Grogan demonstrated that a necrotic disease of bean was caused by a hypersensitivity in resistant cultivars to Bean common mosaic virus; later, he showed this seedborne virus to transmitted by bean pollen.

At Davis, Grogan and associates demonstrated that June yellows in lettuce was caused primarily by the seedborne Lettuce mosaic virus and could be controlled by using virus-free seed. He established that the soilborne chytrid, Olpidium brassicae, transmitted the big-vein agent in lettuce, which was the first report of a fungus as a vector of a disease agent. Later, in Australia, he and a colleague described Lettuce necrotic yellows, a virus disease that served as a model for basic research on bullet-shaped viruses. Grogan found that Tomato mosaic virus could be transmitted mechanically from tomato seed to seedling.

Dr. Grogan discovered that Pseudomonas tomato inhabits and is transmitted by tomato seed, and that P. phaseolicola, cause of halo blight of bean, is a seed contaminant in which sanitation is needed to produce bacterium-free seed. Using nucleic acid hybridization he identified four of six homologous groups of pseudomonads with distinct genotypic characterizations. More recently he and co-workers reported that corky root rot of lettuce is caused by a soilborne gram-positive bacterium, and that this disease can be controlled by cultural practices that improve soil water drainage and aeration.

Grogan’s research led to detection of a new mutant strain of lettuce powdery mildew that is endemic on wild lettuce in California and that caused the mildew epidemics during the 1950s. He incorporated resistance to lettuce downy mildew in Lactuca serriola from Russia into L. sativa and this resistance in the lettuce ‘Calmar’ has been effective for nearly 30 years. In other work, Grogan established: 1) the importance of seed transmission in celery by Septoria apii and that crop rotation and use of disease-free seed are effective controls, 2) that stem canker of tomato is caused by Alternaria alternata, leading to the identifiable stable resistance probably from a single dominant gene, and the identification (with coworkers) of a host-specific toxin useful in screening tomato cultivars for resistance, and 3) that lettuce drop is caused by Sclerotinia minor and S. sclerotiorum with extensive research into the biology, epidemiology, and control of these two species.

Difficult problems in research challenged Dr. Grogan: he determined in the 1950s that the cause of root rot, rapid collapse, and death of lettuce plants in the field was caused by damage from ammoniated nitrate fertilizer. He concluded that high temperatures and calcium deficiency at or near crop maturity contributed to tip burn of lettuce and symptom development.

Few have contributed as much to science and plant pathology as Ray Grogan has. After years of experience, he developed a philosophy that inspired two articles, “The Science and Art of Plant-Disease Diagnosis” and “The role of Genetics in Etiological Pathology and Maintenance of Plant Health.” Throughout his career, Dr. Grogan strove for excellence in himself while instilling it in his students. To him, research should be challenging and fun, and he often compared research to solving a crossword puzzle in which the problem is not solved until all of the squares are filled. His devotion to that philosophy accounted for the many contributions to plant pathology in particular and to agriculture, science, and education in general.

Dr. Grogan died July 30, 2016, at his home in Santa Cruz, CA.