Crown gall can spread between walnut trees in nurseries and reduce future yields
James R. McKenna
Joseph A. Grant
William H. Olson
Wilbur O. Reil
Authors AffiliationsL. Epstein is Professor, Department of Plant Pathology, UC Davis; S. Kaur is Staff Research Associate, Department of Plant Pathology, UC Davis; J.R. McKenna was Staff Research Associate, Department of Pomology, UC Davis, and is currently with the USDA Forest Service at Purdue University; J.A. Grant is Farm Advisor, UC Cooperative Extension (UCCE), San Joaquin County; W.H. Olson is Farm Advisor Emeritus, UCCE Butte County; W.O. Reil is Farm Advisor Emeritus, UCCE Yolo County. We thank Susan Bassein for statistical advice.
Hilgardia 62(3):111-115. DOI:10.3733/ca.v062n03p111. June 2008.
While walnut trees on Juglans hindsiix J. regia ‘Paradox’ rootstocks are highly susceptible to crown gall, it is unknown whether this bacterial disease is acquired in the nursery or the orchard. We selected two groups of gall-free trees in nurseries, those adjacent to trees with and without galls. Two years after being transplanted in the orchard, trees in the group adjacent to those with galls had significantly greater — more than four times more — crown gall incidence than those adjacent to trees without galls (14% versus 3%). In addition, trees in prolonged (17-day), bare-root, unrefrigerated storage before transplanting were associated with higher crown-gall incidence. We also found that crown gall can decrease walnut tree productivity. For every quarter of trunk circumference that was galled, there was a 12% decrease in cumulative nut yield over the first 4 years of production.
Alconero R. Crown gall of peaches from Maryland, South Carolina, and Tennessee and problems with biological control. Plant Dis. 1980. 64:835-8.
Bouzar H, Moore LW, Schaad NW. Crown gall of Agrobacterium strains and potential for biological control in Georgia. Plant Dis. 1983. 67:310-2. doi:10.1094/PD-67-310 https://doi.org/doi:10.1094/PD-67-310
Garrett CME. The effect of crown gall on growth of cherry trees. Plant Pathol. 1987. 36:339-45. doi:10.1111/j.1365-3059.1987.tb02241.x https://doi.org/doi:10.1111/j.1365-3059.1987.tb02241.x
Htay K, Kerr A. Biological control of crown gall: Seed and root inoculation. J Appl Bacteriol. 1974. 37:525-30. PubMed PMID: 4436158
Kainski JM. Bacterial crown gall disease on plants in Kansas. Plant Dis Rep. 1964. 48:664-8.
McKenna JR, Epstein L. Relative susceptibility of Juglans species and interspecific hybrids to Agrobacterium tumefaciens.. Hort Science. 2003. 38:435-9.
Moore LW. Latent infections and seasonal variability of crown gall development in seedlings of three Prunus species. Phytopathol. 1976. 66:1097-101.
Moore LW, Canfield M., Hall R. Biology of Agrobacterium and management of crown gall disease. Principles and Practice of Managing Soilborne Plant Pathogens. 1996. St. Paul, Minn.: APS Pr. p. 153-91.
Pionnat S, Keller H, Héricher D, et al. Ti plasmids from Agrobacterium characterize root-stock clones that initiated a spread of crown gall disease in Mediterranean countries. Appl Environ Microbiol. 1999. 65:4197-206. PubMed PMID: 10473434
Potter D, Gao F, Baggett S, et al. Defining the sources of Paradox: DNA sequence markers for North American walnut (Juglans L.) species and hybrids. Scientia Hort. 2001. 94:157-70.
Smith EF, Brown NA, McCulloch L. The structure and development of crown gall: A plant cancer. USDA Bull No 255. 1912. Washington, DC.: Government Printing Office.
UC IPM. Pest Management Guidelines - Walnut Crown Gall. 2007. UC Statewide Integrated Pest Management Program. http://ucipm. ucdavis.edu/PMG/r881100211.html (updated 12/07).
Young JM, Kuykendall LD, Martinez-Romero E, et al. A revision of Rhizobium Frank 1889, with an emended description of the genus, and the inclusion of all species of Agrobacterium Conn 1942 and Allorhizobium undicola de Lajudie et al. 1998 as new combinations: Rhizobium radiobacter, R. rhizogenes, R. rubi, R. undicola and R. vitis.. Intl J System Evol Microbiol. 2001. 51:89-103.
Also in this issue:Tree Taper Model Volume Equations: II. Tree Taper Models for Major Commercial California Conifers
Focus on the future: Staying relevant in a changing California
Large nesting birds threaten arboretum trees
Safe alternatives to replace invasives in California gardens
Solutions sought to protect valuable blueberries from citrus thrips
San Joaquin Valley blueberries evaluated for quality attributes
Field trials identify more native plants suited to urban landscaping
Pheromone-based pest management can be cost-effective for walnut growers
Glyphosate-resistant hairy fleabane documented in the Central Valley