Methods
Infected bean leaves had been collected from Ontario, Manitoba, Saskatchewan, Alberta and the United States. Bacteria were isolated from the lesions and individual isolates of Xap were preserved. Testing of the different isolates on different bean cultivars indicated differences in aggressivity among the isolates. The bacteria were grown on Petri dishes with milk tween agar and fuscous varieties were identified due to the brown agar. For my part of the project, DNA was isolated from the bacterial isolates grown in liquid media and quantified using a spectrophotometer. Several different extraction procedures were tried and the most successful was the one using a kit. The DNA was then put through a rep-PCR reaction using REP primers. The PCR products were run out on a 1.5% agarose gel and were post-stained with ethidium bromide and visualized using UV light. Results were then analyzed using Ntsys software.
Common bean plants (Phaseolus vulgaris) were inoculated with two strains of bacteria. One was aggressive and the other was non-aggressive. The plants were used to demonstrate the effects of the isolates on the bean plants.
Growing bacteria in liquid media
Extracting DNA