Citrus Huanglongbing: The Pathogen and Its Impact

Fig. 27. Response surface representations of disease development and spatial spread of citrus huanglongbing disease in Reunion Island. The citrus grove was established in 1970. Assessments of disease severity were conducted in 1975 (top), 1977 (middle), and 1979 (bottom) panels, respectively. Note high disease severity around perimeter of western half of grove in 1975, early in the epidemic followed by spread and increase to the east. Final panel is an aerial photo of the Reunion Island HLB plot. Photo is in a similar orientation as the response surface maps in Fig. 2 and was take about the same time as the final disease assessment in 1979. (Photo courtesy of Bernard Aubert).



Image from Plant Health Progress article:
Citrus Huanglongbing: The Pathogen and Its Impact