D3502: Cold survival of Bactericera cockerelli on solanaceous plants: Exploring the impact of “Candidatus Liberibacter solanacearum”

The interactions between plant pathogens and their insect vectors may influence vector biology and ecology, which affect pathogen spread. The potato psyllid, Bactericera cockerelli (Hemiptera: Triozidae), is the vector of “Candidatus Liberibacter solanacearum” (Lso), the bacterial pathogen associated with zebra chip disease (ZC) in potatoes. Lso is also known to negatively affect reproductive output of potato psyllids. There are four distinct haplotypes of B. cockerelli identified in the U.S, and some of these haplotypes are found overwintering on wild solanaceous hosts. The present study was developed to evaluate the survival of different Lso+ and Lso- potato psyllid haplotypes reared on bittersweet nightshade and cultivated potatoes when exposed to cold temperatures (-4℃, 0℃, and 4℃) in the laboratory. Lso significantly increased potato psyllid survivorship in cold temperatures. Potato psyllid survival in low temperatures tended to be consistently higher when reared on bittersweet nightshade than potato plants. Likewise, the temperatures of 0℃ and 4℃ were the most favorable for psyllid survival. Overall, the results presented here indicated that Lso promotes cold tolerance in potato psyllids, which should increase the overwintering success of both the vector and the bacterium.