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UF/IFAS Citrus Research and Education Center

UF/IFAS Citrus Research and Education Center

Publications - Dr. Jim Graham


Program Emphasis

Research focuses on pathogenic and mutualistic microbe relationships of citrus trees and citrus soils, and the development of management tactics that sustain root health.   The goal is to improve integrated management strategies for above- and below-ground diseases and pests that reduce productivity of citrus.

Refereed Publications

Johnson EG, Wu J, Bright DB, Graham JH. 2013. Association of ‘Candidatus Liberibacter asiaticus’ root infection, but not phloem plugging with root loss on huanglongbing-affected trees prior to appearance of foliar symptoms. Plant Pathology https://doi.org/10.1111/ppa.12109

Behlau F, Hong JC, Jones JB, Graham JH. 2013. Evidence for acquisition of copper resistance genes from different sources in citrus-associated xanthomonads. Phytopathology 103: 409-418. https://doi.org/10.1094/PHYTO-06-12-0134-R

Bock CH, Graham JH, Cook AZ, Parker PE, Gottwald TR. 2013. Predisposition of citrus foliage to infection with  Xanthomonas citri subsp.  citri. Journal of Plant Pathology 95:99-106.

Campos-Herrera R, Pathak E, El-Borai FE, Stuart RJ, Gutiérrez C, Rodríguez-Martín JA, Graham JH, Duncan LW. 2013. Geospatial patterns of soil properties and the biological control potential of entomopathogenic nematodes in Florida citrus groves. Soil Biology & Biochemistry 66: 163-174. https://doi.org/10.1016/j.soilbio.2013.07.011

Duncan LW, Stuart RJ, El-Borai FE, Campos-Herrera R, Pathak E, Giurcanu M, Graham JH. 2013. Modifying orchard planting sites conserves entomopathogenic nematodes, reduces weevil herbivory and increases citrus tree growth, survival and fruit yield. Biological Control 64: 26–36. https://doi.org/10.1016/j.biocontrol.2012.09.006

Graham JH, Johnson EG, Gottwald TR, Irey M. 2013. Pre-symptomatic fibrous root decline in citrus trees caused by Huanglongbing and potential synergistic interaction with Phytophthora spp. Plant Disease 97: 1195-1199. https://doi.org/10.1094/PDIS-01-13-0024-RE

Graham JH, Myers, ME. 2013. Integration of soil applied neonicotinoid insecticides and acibenzolar-S-methyl for systemic acquired resistance (SAR) control of citrus canker on young citrus trees. Crop Protection 54:239-243. https://doi.org/10.1016/j.cropro.2013.09.002

Jalan N, Kumar D, Andrade MO, Yu FH, Jones JB, Graham JH, White FF, Setubal JC, Wang N. 2013. Comparative genomic and transcriptome analyses of pathotypes of Xanthomonas citri subsp.  citri provide insights into mechanisms of bacterial virulence and host range. BMC Genomics14: 41500. https://doi.org/10.1186/1471-2164-14-551

Johnson NC, Graham JH. 2013. The continuum concept remains a useful framework for studying mycorrhizal functioning. Plant and Soil 363: 411-419. https://doi.org/10.1007/s11104-012-1406-1

Llorens E, Lapena L, Graham JH, Garcia-Agustin P. 2013. A first approach to the use of hexanoic acid as a resistance inducer against Xanthomonas citri. IOBC/WPRS Bulletin 89: 205-209.

Duncan, L.W., Stuart, R.J., El-Borai, F.E., Campos-Herrera, R., Pathak, E., Giurcanu, M., Graham, J.H. 2012. Modifying orchard planting sites conserves entomopathogenic nematodes, reduces weevil herbivory and increases citrus tree growth, survival and fruit yield. Biocontrol 64:26-36. https://doi.org/10.1016/j.biocontrol.2012.09.006

Gottwald, T.R., Graham, J.H., Irey, M. S., McCollum, T.G., and Wood, B.W. 2012. Inconsequential effect of nutritional treatments on Huanglongbing control, fruit quality, bacterial titer and disease progress. Crop Protection. 36:73-82. https://doi.org/10.1016/j.cropro.2012.01.004

Behlau F., Jones, J. B., Myers, M. E. and Graham, J. H. 2012. Monitoring for resistant populations of Xanthomonas citri subsp. citri and epiphytic bacteria on citrus trees treated with copper or streptomycin using a new semi-selective medium. European Journal of Plant Pathology 132:259–270. https://doi.org/10.1007/s10658-011-9870-7

Golmohammadi, M., Llop, P., Scuderi, G., Gell, I., Graham, J. H. and J. Cubero. 2012. mRNA from selected genes is useful for specific detection and quantification of viable Xanthomonas citri subsp. citri.  Plant Pathology 61: 479–488 https://doi.org/10.1111/j.1365-3059.2011.02526.x

Bock, C.H., Gottwald, T.R., Cook, A.Z., Parker and P.E. Graham, J.E. 2011. The effect of wind speed on dispersal of splash-borne Xanthomonas citri subsp citri at different heights and distances downwind of canker-infected grapefruit trees. Journal of Plant Pathology 93: 667-677.

Bock, C.H., Cook, A.Z., Parker, Gottwald, T.R. and P.E. Graham, J.E. 2012. Short distance dispersal of splashed bacteria of Xanthomonas citri subsp citri from canker-infected grapefruit tree canopies in turbulent wind. Plant Pathology 61: 829-836. https://doi.org/10.1111/j.1365-3059.2011.02588.x

Pathak, E., El-Borai, F.E., Campos-Herrera, R., Johnson, E.G., Stuart, R.J., Graham, J.H., Duncan, L.W. 2012. Use of real-time PCR to discriminate parasitic and saprophagous behavior by nematophagous fungi. Fungal Biology 115, 563–573. https://doi.org/10.1016/j.funbio.2012.02.005

Behlau, F., Graham, J. H., and Jones, J. B. 2012. Copper resistance genes from different xanthomonads and citrus epiphytic bacteria confer resistance to Xanthomonas citri subsp. citri. European Journal of Plant Pathology 133:949-963. https://doi.org/10.1007/s10658-012-9966-8

Chellemi, D.O., Wu, T., Graham, J.H., Church, G., 2012. Biological impact of divergent land management practices on tomato crop health. Phytopathology. 102: 597-608. https://doi.org/10.1094/PHYTO-08-11-0219

Graham, J.H., Colburn, G.C., Chung, K.-R., and Cubero, J. 2012. Protection of citrus roots against infection by Phytophthora spp. by hypovirulent P. nicotianae is not related to induction of systemic acquired resistance. Plant and Soil 358:39–49. https://doi.org/10.1007/s11104-011-1119-x

Larsen, J., Graham, J. H., Cubero J. and Ravnskov, S. 2012. Biocontrol traits of plant growth suppressive arbuscular mycorrhizal fungi against root rot in tomato caused by Pythium aphanidermatum. European Journal of Plant Pathology 133:361–369. https://doi.org/10.1007/s10658-011-9909-9

Figueiredo J. F., Römer P., Lahaye T., Graham J.H., White F.F., Jones J.B. 2011. Agrobacterium-mediated transient expression in citrus leaves: a rapid tool for gene expression and functional gene assay. Plant Cell Rep. 30: 1339–1345. https://doi.org/10.1007/s00299-011-1045-7

Campos-Herrera, R., El-Borai F.E., Stuart R.J., Graham J.H., Duncan, L.W. 2011. Entomopathogenic nematodes, phoretic Paenibacillus spp., and the use of realtime quantitative PCR to explore soil food webs in Florida citrus groves. J. Invertebrate Pathology 108: 30–39. https://doi.org/10.1016/j.jip.2011.06.005

Cubero, J., I. Gell, E.G. Johnson, A. Redondo, and J.H. Graham. 2011. Unstable green fluorescent protein for study of Xanthomonas citri subsp citri survival on citrus. Plant Pathology 60:977-985. https://doi.org/10.1111/j.1365-3059.2011.02450.x

Graham, J.H., and Myers, M.E. 2011. Soil drenches of imidacloprid, thiamethoxam and acibenzolar-S-methyl for induction of SAR to control citrus canker in young citrus trees. Plant Dis. 95:725-728. https://doi.org/10.1094/PDIS-09-10-0653

Campos–Herrera, R., Johnson, E., El–Borai, F.K., Stuart, R.J., Graham, J.H., and Duncan, L.W. 2011. Long-term stability of entomopathogenic nematode spatial patterns measured by sentinel insects and real-time PCR assays. Annals of Applied Biology 158: 55-68. https://doi.org/10.1111/j.1744-7348.2010.00433.x

Behlau, F., Canteros, B.I., Minsavage, G.V., Jones, J.B., and Graham J.H. 2011. Molecular characterization of copper resistance genes from Xanthomonas citri subsp. citri and Xanthomonas alfalfa subsp. citrumelonis. Applied Environmental Microbiology 77: 4089–4096. https://doi.org/10.1128/AEM.03043-10

Figueiredo, J, Minsavage, G.V., Graham, J.H., White, F.F., and Jones, J.B. 2011. Mutational analysis of Type III effector genes from Xanthomonas citri subsp. citri. European Journal of Plant Pathology 130:339–347. https://doi.org/10.1007/s10658-011-9757-7

Francis, M.I., Kostenyuk I., Orbovic, V., Loskutov, A, Zolotukhin, M. and Graham, J.H. 2011. Automated Needle-free Injection Method for Delivery of Bacterial Suspensions into Citrus Leaf Tissues. Journal of Phytopathology 159:347-351. https://doi.org/10.1111/j.1439-0434.2010.01774.x

Graham, J. H. 2011. Phosphite for control of Phytophthora diseases in citrus: model for management of Phytophthora species on forest trees? New Zealand Journal of Forestry Science 41 Suppl.: S49-S56.

Bock, C. H., P.E. Parker, A.Z. Cook, J.H. Graham, and T.R. Gottwald. 2011. Infection and decontamination of citrus canker-inoculated leaf surfaces. Crop Protection 30:259-264. https://doi.org/10.1016/j.cropro.2010.10.001

Bock, C.H., Graham, J.H., Gottwald, T.R., Cook, A.Z., and Parker, P.E. 2010. Wind speed and wind associated injury affect severity of citrus canker on Swingle citrumelo. European Journal of Plant Pathology 128: 21-38. https://doi.org/10.1007/s10658-010-9624-y

Bock, C.H., Graham, J.H., Gottwald, T.R., Cook, A.Z., and Parker, P.E. 2010. Wind speed effects on the quantity of Xanthomonas citri subsp. citri dispersed downwind from canopies of grapefruit trees infected with citrus canker. Plant Disease 94: 725-736. https://doi.org/10.1094/PDIS-94-6-0725

Zhang, X., Francis, M.I., Dawson , W.O., Graham, J.H., Orbovic V., Triplett, E.W., and Mou, Z. 2010. Overexpression of Arabidopsis NPR1 gene in citrus increases resistance to citrus canker. European Journal of Plant Pathology 128:91-100. https://doi.org/10.1007/s10658-010-9633-x

Francis, M.I., Peña, A., and Graham, J.H. 2010. Detached leaf inoculation of germplasm for rapid screening of resistance to citrus canker and citrus bacterial spot. European Journal of Plant Pathology 127:571–578. https://doi.org/10.1007/s10658-010-9620-2

Behlau, F., Amorim, L., Belasque Jr, J., Bergamin Filho, A., Leite Jr., R.P., Graham, J.H., and Gottwald, T.R. 2010. Annual and polyetic progression of citrus canker on trees protected with copper sprays. Plant Pathology 59:1031-1036. https://doi.org/10.1111/j.1365-3059.2010.02344.x

Behlau F., J. Belasque Jr., J.H. Graham, R.P. Leite Jr. 2010. Effect of frequency of copper applications on control of citrus canker and the yield of young bearing sweet orange trees. Crop Protection 29:300–305. https://doi.org/10.1016/j.cropro.2009.12.010

Francis, M.I., Redondo, A., Burns, J.K., and Graham, J.H. 2009. Soil application of imidacloprid and related SAR-inducing compounds produces effective and persistent control of citrus canker. European J. Plant Path. 124:283-292 https://doi.org/10.1007/s10658-008-9415-x

Gottwald T., Graham, J., Bock, C., Bonn, G., Civerolo, E., Irey, M., Leite, R., McCollum, G., Parker, P., Ramallo, J., Riley, T., Schubert, T., Stein B., Taylor, E. 2009. The epidemiological significance of post-packinghouse survival of Xanthomonas citri ssp. citri for dissemination of Asiatic citrus canker via infected fruit. Crop Protection 28:508-524. https://doi.org/10.1016/j.cropro.2009.02.003

Rasmann, C., J.H. Graham, D.O. Chellemi, L.E. Datnoff, and J. Larsen. 2009. Resilient populations of root fungi occur within five tomato production systems in southeast Florida. Appl. Soil Ecol. 43:22-31. https://doi.org/10.1016/j.apsoil.2009.05.007

Refereed Proceedings

Graham, J.H. 2011. Systemic acquired resistance for bacterial canker disease management in citrus. Tropical Plant Pathology 36 (suppl.): 87-89.

Graham, J.H., Johnson, E.G., Bright, D.B., and Irey, M.S. 2011. Lack of development of Huanglongbing in seedlings from citrus seed. Proc. Fla. State Hort. Soc. 124:79–84.

Graham J.H., Dewdney, M.M. and Yonce, H.D. 2011. Comparison of copper formulations for control of citrus canker on ‘Hamlin’ orange. Proc. Fla. State Hort. Soc. 124:79–84.

Graham, J.H., Dewdney, M.M., and Myers, M.E. 2010. Streptomycin and copper formulations for control of citrus canker on grapefruit. Proc. Fla. State Hort. Soc. 123:92–99.

Non-refereed Publications

Futch, S. H. and Graham, J. H. 2012 Susceptibility of common rootstocks and scions to foliar citrus canker under Florida conditions. Proc. Fla. State Hort. Soc. 125:47-49.

Graham, J.H., B. Stein, and R.P. Leite, Jr. 2011. Management challenges posed by citrus canker for production of highly susceptible grapefruit in Florida. Proc. Intern. Citrus Congress Wuhan China, October 26-30. Vol. 2: 1055-1059.

Graham, J.H., M.S. Irey and Reed, C. 2010. Assay of citrus seed for viable Xanthomonas citri pv. citri (Xcc) after extraction from fruit affected by citrus canker. Proc. Fla. State Hort. Soc. 123:350.

Turechek, W.W., Irey, M., Sieburth, P., Brlansky, R., DaGraça, J., Graham, J., Gottwald, T., Hartung, J., Hilf, M., Kunta, M., Manjunath, K., Lin, H., Ramadugu, C., Roberts, P., Rogers, M., Shatters, R., Sun, X., and Wang, N. 2009. Evaluation of Quantitative Real-Time PCR Assays for Detection of Citrus Greening. p. 158-160 in: Proc. 10th Int. Epidem. Workshop, Geneva, NY.

Popular Articles

Graham, J., Johnson, E., Gottwald, T. R. and Irey, M. 2013 Integrated management of root health on HLB-affected trees. Citrus Ind. 94(2): 12-14.

Graham, J., Gruber, B. Bock, C. 2013. Integrated management of citrus canker. Citrus Ind. 94(4): 12, 14-17.

Graham, J., Gottwald, T., and Irey, M. 2012. Balancing resources for management of root health in HLB-affected groves. Citrus Ind. 93(7):6-11.

Graham, J. and M. Dewdney. 2012. Research Progress for Management of Citrus Canker in 2012. Citrus Ind. 93(3): 15-17.

Timmer, L.W., Bové, J.M., Ayres, A.J., Bassanezi, R.B., Belasque Jr., J, Chamberlain, H.L., Dawson, W.O., Dewdney, M.M., Graham, J.H., and Irey, M. 2011. HLB: It's not too late – yet. Citrus Ind. 92(1), 6-7.

Graham, J. and M. Dewdney. 2011. Citrus canker management update. Citrus Ind. 92(3):6-10.

Graham, J. 2011. Canker Control. Florida Grower 104 (8):26-27.

Graham, J. and Vallad, G. 2011. The ABCs of SAR. Citrus Ind. 92(5):10-15.

Graham, J., Irey, M. and Taylor, J. 2011. Phytophthora damage to roots: a potential contributor to decline of HLB-affected trees. Citrus Ind. 92(5):20-23.

Graham, J. 2011. Cooperative Producers: Integrating best management practices for HLB. Citrus Ind. 92(10):10-12.

Graham, J. and M. Dewdney. 2010. Management recommendations for citrus canker in 2010. Citrus Ind. 91(3):10-12.

Graham, J. 2010. Citrus black spot lessons from Brazil. Citrus Ind. 91(10): 6-8.

Graham, J. and Dewdney, M. 2009. Management recommendations for citrus canker in 2009. Citrus Industry 90(2): 22-25, 31.

Dewdney, M. and J. Graham. 2009. Cooperative Producers keep greening under control. Citrus Industry 90(9): 5-8.