2010 Annual Report
2. Develop/refine rapid, sensitive reliable detection/sampling methods for pathogens.
3. Develop or improve comprehensive integrated disease management strategies. a. Assess the impact of a wide array of control/mitigation/therapeutic strategies on Huanglongbing (HLB) and the Asian citrus psyllid epidemiology to evalute optiumu means of disease control.
Continuing disinfectant trials have identified several effective sanitation protocols for eliminating tobamoviruses from cutting tools during propagation and production of ornamentals.
Huanglongbing (HLB), the most devastating citrus disease, is widespread in Florida, and is an impending threat to the citrus in California and Texas. Monoclonal antibodies against the HLB pathogen and reagents for qPCR and nested PCR were developed and have been transferred to university and state regulatory laboratories for diagnostic and basic research purposes. Genome sequencing of Ca. L. solanacearum (Las), the causal agent of potato zebra chip, has been initiated and a complete genome of 1.25 Mb has just been obtained. Functional genomics of Las, such as characterization of ATP translocase, putative Zinc uptake operons has been carried out. The genetic diversity of the Las bacterium has been revealed, which is associated with phenotype variations of the HLB diseases. Seed transmission of Las is being investigated using several different approaches.
A stochastic statewide stratified survey program for HLB/canker/citrus variegated chlorosis/citrus leprosis virus/black spot continued to be used in 2010 and was further adapted to determine the distribution of HLB and its vector the Asian citrus psyllid to target areawide control efforts. The method will be used for a delimiting survey for black spot in Florida to determine how far the disease has spread. A new predictive model has been developed based on travel and US census information to predict introductions of plant pathogens and pests and has possible adaptation to animal and human disease prediction as well. Rapid detection methods for HLB were developed based on a spectral analyses of chemical changes in plant tissues that could aid in both early detection and the processing of large numbers of samples.
Hall, D.G., Gottwald, T.R., Nguyen, N.C., Ichinose, K., Le, Q.D., Beattie, G.A.C., Stover, E. 2008. Greenhouse investigations on the effect of guava on infestations of Asian citrus psyllid in grapefruit. Proceedings Florida State Horticultural Society. 121:104-109 Parnell, S., Gilligan, C., Gottwald, T.R., Cunniffe, N., Van Den Bosch, F. 2009. The effect of landscape pattern on the optimal eradication zone of an invading epidemic. Phytopathology. Vol. 100, No. 7:638-644. Hawkins, S.A., Park, B., Poole, G.H., Gottwald, T.R., Windham, W.R., Lawrence, K.C. 2010. Detection of Citrus Huanglongbing by Fourier Transform Infrared-Attenuated Total Reflection (FTIR-ATR) Spectroscopy. Applied Spectroscopy. 64:100-103. Bock, C., Parker, P., Cook, A., Gottwald, T.R. 2009. Automated image analysis of the severity of foliar citrus canker symptoms. Plant Disease. 93:660-665 Parker, P., Bock, C., Cook, A., Gottwald, T.R. 2008. Dispersal of Xanthomonas citri subsp. citri bacteria downwind from harvested, infected fruit. Phytopathology. 98:S121 Hawkins, S.A., Park, B., Poole, G.H., Gottwald, T.R., Windham, W.R., Albano, J.P., Lawrence, K.C. 2010. Comparison of FTIR spectra between huanglongbing (citrus greening) and other citrus maladies. Journal of Agricultural and Food Chemistry. 58(10):6007-6010. Chellemi, D.O., Von Wedel, R., Adkins, S.T., Turechek, W. 2010. Integrating Sunflower Oil Seed Crops into Florida Horticultural Production Systems. Proceedings of Florida State Horticultural Society. 122:289-294. Lewandowski, D., Hayes, A.J., Adkins, S.T. 2010. Surprising results from a search for effective disinfectants for Tobacco mosaic virus-contaminated tools. Plant Disease. 94:5:542-550. Webster, C.G., Perry, K., Lu, X., Horsman, L., Frantz, G., Mellinger, C., Adkins, S.T. 2010. First report of Groundnut ringspot virus infecting tomato in south Florida. Plant Health Progress. doi:10.1094/PHP-2010-0707-01-BR. Matos, L., Hilf, M.E., Comejo, J. 2009. First report of Candidatus Liberibacter asiaticus infecting citrus in the Dominican Republic. Plant Disease. 93:668. Gent, D.H., Turechek, W., Mahaffee, W.F. 2008. Spatial and Temporal Stability of the Estimated Parameters of the Binary Power Law. Phytopathology. 98:1107-1117. Zhang, M., Duan, Y., Turechek, W., Stover, E.W., Powell, C.A. 2010. Screening molecules for control of citrus Huanglongbing (HLB) using an optimized regeneration system for 'Candidatus Liberibacter asiaticus' infected periwinkle (Catharunthus roseus) cuttings. Phytopathology. 100:239-245. Lin, H., Chen, C., Doddapaneni, H., Duan, Y., Civerolo, E.L., Bai, X., Zhao, X. 2010. A New Diagnostic system for Ultra Sensitive and Specific Detection and Quantitation of “Candidatus Liberibacter asiaticus”, the Bacterium Associated with Citrus Huanglongbing. Journal of Microbiological Methods. 81(1):17-25. Li, W., Abad, J.A., French-Monar, R.D., Rascoe, J., Wen, A., Gudmestad, N.C., Secor, G.A., Lee, I., Duan, Y., Levy, L. 2009. Multiplex real-time PCR for detection, identification and quantification of ‘Candidatus Liberibacter solanacearum’ in potato plants with zebra chip. Journal of Microbiological Methods. 78:59-65. Trivedi, P., Duan, Y., Wang, N. 2010. Citrus huanglongbing shapes the structure of bacterial community associated with citrus roots. Applied and Environmental Microbiology. Bock, C., Poole, G.H., Parker, P., Gottwald, T.R. 2010. Estimation of plant disease severity visually, by digital photography and image analysis, and by hyperspectral imaging. Critical Reviews in Plant Sciences. 29:59-107 Bock, C., Gottwald, T.R., Parker, P., Ferrandino, F., Parnell, S., Van Den Bosch, F. 2009. Horsfall-Barratt recalibration and replicated severity estimates of citrus canker . European Journal of Plant Pathology. 125:23-38. Turechek, W., Kousik, C.S., Adkins, S.T. 2010. Patterns of Virus Distribution in Single and Mixed Infections of Florida Watermelons. Phytopathology. doi:10.1094/PHYTO-01-10-0018. Wu, Z., Wu, J., Adkins, S.T., Xie, L., Li, W. 2010. Rice ragged stunt virus segment S6-encoded nonstructural protein Pns6 complements cell-to-cell movement of Tobacco mosaic virus-based chimeric virus. Virus Research. 152:176-179. Adkins, S.T., Webster, C.G., Baker, C.A., Weaver, R., Rosskopf, E.N., Turechek, W. 2009. Detection of three whitefly-transmitted viruses infecting the cucurbit weed, Cucumis melo var. dudaim, in Florida. Plant Health Progress. doi:10.1094/PHP-2009-1118-01-BR Folimonova, S., Robertson, C., Shilts, T., Folimonov, A., Hilf, M.E., Garnsey, S., Dawson, W. 2010. Strains of Citrus tristeza virus do not exclude superinfection by other strains of the virus. Journal of Virology. 84:1314-1325. Webster, C.G., Adkins, S.T., Perry, K., Lu, X., Horsman, L., Frantz, G., Mellinger, C. 2010. Groundnut ringspot virus detected infecting tomato in south Florida. Pest Alert. http://entomology.ifas.ufl.edu/pestalert/groundnut_ringspot.htm Gottwald, T.R. 2010. CURRENT EPIDEMIOLOGICAL UNDERSTANDING OF CITRUS HUANGLONGBING. Annual Review of Phytopathology. 48:119-139.