Spatial and Temporal Distribution of <i>Iris yellow spot virus</i> and Thrips in Colorado Onion Fields

Fig. 1. Spatial distribution of the density of thrips (upper row) and the corresponding incidence of iris yellow spot (IYS) (lower row) on 12 July (A), 8 August (B), and 15 August (C) at the Peckham direct-seeded onion bulb field in 2005 in Colorado. Dark green areas indicate where thrips density or incidence of IYS was 0, while red indicate areas of highest thrips density (57.0/plant) or IYS incidence (97.2%). Maps were produced from data interpolated using the inverse distance weighting technique based on the assumption that the interpolating surface should be influenced most by the nearby points and less by the more distant points (19).



Image from Plant Health Progress article:
Spatial and Temporal Distribution of Iris yellow spot virus and Thrips in Colorado Onion Fields