Effectiveness of micronized fluorescent powder for marking citrus psyllid, Diaphorina citri

Abstract

Asian citrus greening disease (CGD) is caused by Candidatus Liberibacter asiaticus, transmitted by the Asian citrus psyllid, Diaphorina citri Kuwayama. An effective method for controlling the pathogen is currently unavailable; therefore, controlling psyllids is a more practical strategy for minimizing damage from CGD. However, ecological/ethological field studies on this insect are limited due to a lack of effective marking methods. This study examined the effectiveness of a marking method for psyllids using fluorescent powder (FZ-2803). Equal numbers of marked and unmarked psyllids were released at a distance of 2 m from a light. The collection of marked psyllids near the light was significantly lower than that of unmarked psyllids until 4 h after marking. After 5 h, no significant difference was observed. No significant differences in mortality were detected between the two groups during a 40-day period after marking. The persistence of a mark on the psyllid body was confirmed visually in the laboratory for 40 days. One hundred marked psyllids were released in an orange jasmine field (18 m×18 m). The marked insects were detected visually, and the proportion of marked insects was 30% after 20 days and 20% after 40 days. These results indicate that the marking method using fluorescent powder does not affect survival, and it can be used for ca. 5 weeks in the field.