| prevalence, incidence, and spatial dependence of soybean mosaic virus in iowa. | the prevalence of soybean fields with plants infected with soybean mosaic virus (smv) in iowa is assumed to be random, because the primary source of the virus is smv-infected seed. data collected from 2,500 soybean fields sampled over a 3-year period as part of the iowa soybean disease survey (2005 to 2007) were used to evaluate this assumption. smv was first detected in early june of each year but counties in which it was first detected varied among years. prevalence at the county scale at end ... | 2010 | 20701491 |