The potato psyllid (Bactericera cockerelli) is an emerging pest of solanacious crops. Traditionally their range expanded from Guatemala north through the central United States and into southern California. Recent expansions have led to potato psyllids residing as far south as Nicaragua and as for north as Washington State. Potato psyllids were also accidentally imported into New Zealand. These expansions are alarming because potato psyllids transmit Candidatus Liberibacter solanacaerum (Lso), the bacteria associated with Zebra Chip disease in potato, which results in millions of dollars in damages annually. In this study, potato psyllid and Zebra Chip range expansion into Central America was explored; the current method of detecting Lso was compared to pyrosequencing to identify irregularities in infections of psyllids in fields and research labs; and the microbial communities of potato psyllids were used to assess differences between populations and to provide evidence of migration patterns. The results of this research indicate that potato psyllids and Zebra Chip disease are spreading throughout Central America and infecting new plants such as tobacco, which could have severe economic impacts on the region. Current methods of detecting Lso are not sensitive enough to detect the pathogen at low levels of infection. Surveys of potato psyllid microbial communities provided insight into the population dynamics of potato psyllids. Potato psyllids in different regions contain drastically different microbial communities, mainly influenced by the proportions of Wolbachia and Candidatus Carsonella rudii. Haplotype, year, and host plant unexpectedly did not have an impact on potato psyllid microbial community.
Date of publication
Arp, Alex, "BACTERICERA COCKERELLI: RANGE EXPANSION, CANDIDATUS LIBERIBACTER SOLANACAERUM DETECTION, AND MICROBIAL COMMUNITY ANALYSIS" (2013). Biology Theses. Paper 7.