POSTERS: Pathogenicity and host specificity
‘Candidatus Liberibacter solanacearum’ haplotypes differentially affect seed-potato sprouting
Fekede Workneh - Texas A&M AgriLife Research. Jordan Trees- Texas A&M AgriLife Research, Charles Rush- Texas A&M AgriLife Research, Li Paetzold- Texas A&M AgriLife Research
‘Candidatus Liberibacter solanacearum’ (Lso), putatively causes potato zebra chip and there are currently two widely recognized haplotypes (A&B) of Lso infecting potatoes in the US. However, the relative impact of the haplotypes on tuber sprouting is unknown. To address the issue, two separate studies were conducted in which sixteen-to-twenty tubers, verified to be infected with individual haplotypes (A, B, or A+B), were planted in the greenhouse in 2018-2019 in a randomized complete-block design. Emergence was monitored daily over a six-week period. At the end, plant height, stem width, leaf area (LA), and plant biomass were determined. In both studies, plant emergence from tubers infected with Lso A (80%) was not significantly different from those of uninfected controls (97%). However, plant emergence from tubers infected with Lso B was significantly lower (60%) than that of the controls (Chi Square, ?=0.05). Emergence of plants from tubers infected with A&B was not consistently different from those of uninfected tubers although it was numerically greater than those from tubers infected with Lso B. Plants from tubers infected with Lso B took a longer time to emerge than those from tubers infected with Lso A or uninfected controls, which had similar length of time for emergence. All plant measurements (biomass, height, LA, and stem width) were significantly higher for plants that emerged from the controls than those from infected tubers regardless of the haplotype (?=0.05).