“The effects of an established presence of ‘Candidatus Liberibacter solanacearum’ in the midgut of the potato psyllid nymph”
The potato psyllid (Bactericera cockerelli) is responsible for the transmission of ‘Candidatus Liberibacter solanacearum’ (Lso), an economically important bacterial pathogen that affects solanaceous crops. There are currently two haplotypes of Lso found in America, Lso A and B. With Lso B causing more severe symptoms in comparison with Lso A. Lso is transmitted in a persistent circulative manner by psyllids; and nymphs are efficient vectors. The gut is the first barrier that Lso needs to cross in the insect for transmission. Therefore, understanding the molecular mechanisms at play in the psyllid gut during Lso transmission could lead to the development of control strategies to disrupt pathogen transmission. However, if an acquired or established presence of Lso plays a role in the nymph gut is currently unknown. By using nymphs from laboratory colonies, I was able to compare 3rd and 5th nymphal instars harboring either Lso A or Lso B. I was able to determine the transmission rate, effects on programmed cell death, and nuclear and cellular structures using fluorescent microscopy for each haplotype. There were no significant differences between Lso A or B or either instar.