The Asian citrus psyllid, Diaphorina citri, is the vector for the bacteria causing the citrus disease Huanglongbing. This disease had been destroying Florida’s citrus industry since its introduction in 1998. In north Florida, research investigating the distribution and the penology of D. citri throughout north Florida has been conducted over a 2-year period from 2017 to 2019. Diaphorina citri adults peaked in July and were found throughout the winter months despite temperatures dropping to -5.5°C. Experiments with caged D. citri under ambient temperatures from December to March for two consecutive winters were conducted. We found that 21% percent of D. citri survived the first winter and 19% survived the second. These survival rates were higher than what we would expect from the literature. To mimic field conditions, laboratory cold tolerance experiments have been conducted using reared psyllids. Results show no significant survival rate differences between psyllid color or gender. However, survival did increase when psyllids were introduced to gradual drops in temperature from 24 to -4 degrees Celsius. Over a two-week period, results show a 90% higher survival rate in psyllids that were gradually dropped to -4 degrees Celsius. In comparison, the control group was kept at 24 degrees Celsius over the two-week period and then dropped to -4 degrees Celsius. The control group showed a survival rate of 20% in these conditions. These results suggest that the survival of Asian citrus psyllids in north Florida is facilitated by cold acclimation.
