Leaf Wetness, Warning Systems, and Site-Specific Weather Data


A goal of my program is to help growers acquire the weather data they need to operate disease-warning systems reliably and conveniently.
In a project funded by a USDA/RAMP grant, our team (including ISU meteorologists Elwynn Taylor and Eugene Takle, Kwang-Soo Kim from HortResearch in Auckland, New Zealand, and plant pathologists Bob Seem of Cornell University, Mary Hausbeck of Michigan State University, and Walt Stevenson of University of Wisconsin) is conducting a 3-year (2006-2008), 4-state validation of implementing disease-warning systems for apples, carrots, potatoes, watermelons, and grapes with site-specific weather estimates (SkyBit, Inc.), using models by Kim et al. (Agricultural and Forest Meteorology 127:53-64, 2004) to enhance the accuracy of leaf wetness duration estimates.

 A recent collaboration with Drs. Terry Gillespie (University of Guelph) and Paulo Sentelhas (ESALQ, Piracicaba, Brazil) focused on heterogeneity of leaf wetness duration (Sentelhas et al., 2005, Int. J. Biomet. 49:363-370) and estimating in-canopy wetness from measurements made outside agricultural fields (Sentelhas et al., 2004, Agric. and Forest Met. 126:59-72).

Eduardo Monteiro, a PhD student of Dr. Sentelhas in agricultural meteorology at Piracicaba, is visiting our lab from March-August 2006. Eduardo is collaborating with Dr. Paul Esker, a postdoc in X.B. Yang’s lab at ISU, on analysis of Eduardo’s data set from Brazil on epidemiology of anthracnose (also called ramulosis; pathogen:Colletotrichum gossypii var. cephalosporioides). Eduardo is also advising Jean Batzer on analysis of her data set on heterogeneity of leaf wetness duration in apple tree canopies, and advising Katie Duttweiler on analysis of her data sets for refinement of a SBFS warning system.