Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: May 16, 2011
Publication Date: June 30, 2011
Citation: Olanya, O.M., Larkin, R.P., He, Z., Jain, S., Honeycutt, C. 2011. Survival potential of Phytophthora infestans sporangia in relation to meteorological factors. American Phytopathological Society Abstracts. 101:6, S132. Technical Abstract: Assessment of meteorological factors coupled with sporangia survival curves may enhance effective management of potato late blight, caused by Phytophthora infestans. We utilized a non-parametric density estimation approach to evaluate the cumulative probability of occurrence of temperature and relative humidity conducive for late blight outbreak at a potato production field site at Presque Isle, ME. Sporangia survival probabilities were computed based on microclimatic data. The influence of solar radiation on sporangia survival potential was also determined, based on modified pathogen survival model. The joint distribution of temperature and relative humidity were similar among years, and favorable for late blight outbreak. Sporangia survival duration and frequency coincided with the potential period for pathogen infection during the cropping cycles. Sporangia survival probability (SSP) ranged from 0-64%, but had variable frequency and temporal changes during the cropping cycle. Analyses of SSP showed that 5-10% of cropping cycle is associated with 48-64% survival probabilities. High humidity and low temperatures were correlated with low solar radiation, with increased risk of high SSP and disease outbreak. By modeling periods of elevated survival potential in diverse locations and production regions, precise forecasts and disease controls can be optimized. P. infestans survival curves and climatic variables can be utilized in predictions of late blight on potato tubers and for better disease controls.