Location: Horticultural Crops Research
2013 Annual Report
Objective 1C: We have compared the ability of different Phytophthora species to infect the host plant Rhododendron. Two pathogens, P. plurivora and P. syringae appear to be the most aggressive under warm and cold temperatures, respectively.
Objective 1D: We developed a novel spore trapping system that can be used to capture airborne spores released after specific temperature and wetness periods. We developed techniques to simulate grape bark wetting and drying that will allow for greater experimental control and flexibility than using grape trunks to experimentally manipulate overwintering conditions and test their impact on cleistothecia. These advances will allow us to better determine the exact conditions required for ascospore release and improve disease forecasting.
Objective 2A: We sampled foliar infections of Rhododendron to assess which species of Phytophthora are dominant. P. syringae and P. plurivora are the two dominant species causing foliar Phytophthora disease on Rhododendron in the Pacific Northwestern US.
Objective 2C: We demonstrated that leaf removal occurring as early as BBCH growth 53 did not reduce yield or grape quality but reduced severity powdery mildew and bunch rot. These results indicate the growers can pull leaves earlier in the season improve disease control without increasing production costs.
Objective 2D: We demonstrated that loop mediated isothermal amplification can be used by growers to detect the grape powdery mildew pathogen and time fungicide applications. The significantly lower capital costs and simplicity of the technique indicate that this tool could be commercially viable for disease management.Utro, F., Haiminen, N., Livingstone Iii, D., Cornejo, O.E., Royaert, S., Schnell, R.J., Motamayor, J.C., Kuhn, D.N., Parida, L. 2013. iXora1: exact haplotype inferencing and trait association. BioMed Central (BMC) Genetics. 14:48.
Faukner, J., Rawles, S.D., Proctor, A., Sink, T.D., Chen, R., Philips, H., Lochmann, R.T. 2013. The effects of diets containing standard soybean oil, soybean oil enhanced with conjugated linoleic acids, menhaden fish oil, or an algal docosahexaenoic acid supplement on channel catfish performance, body composition, sensory evaluation, and storage characteristics. North American Journal of Aquaculture. 75:252–265.
Fry, W.E., Mcgrath, M.T., Seaman, A., Zitter, T.A., Mcleod, A., Danies, G., Small, I.M., Myers, K., Everts, K., Gevens, A.J., Gugino, B.K., Johnson, S.B., Judelson, H., Ristaino, J., Roberts, P., Secor, G., Seebold, K., Snover-Clift, K., Wyenandt, A., Grunwald, N.J., Smart, C.D. 2013. The 2009 late blight pandemic in eastern USA – causes and results. Plant Disease. 97:296-306.
Berbegal, M., Perez-Sierra, A., Armengol, J., Grunwald, N.J. 2013. Evidence for multiple introductions and clonality in Spanish populations of Fusarium circinatum. Phytopathology. 103:851-861.
Gent, D.H., Mahaffee, W.F., Mcroberts, N., Pfender, W.F. 2013. The use and role of predictive systems in disease management. Annual Review of Phytopathology. 51:267-89.