Cucumber (Cucumis sativus) is an important agricultural plant that, in addition to other pathogens, is also threatened by various viroids, including hop stunt viroid (HSVd). Infection with HSVd causes deformities in plants, stunted growth and yield reduction, which is a major economic problem. The aim of this master's thesis was to compare the efficiency of different types of inoculum for the transmission of HSVd in cucumbers and to investigate possible alternative sources of inoculum. As part of the experiment, we prepared RNA transcripts in positive and negative orientation, a plasmid with HSVd transcript and a PCR product with HSVd transcript. Two cucumber varieties, 'Suyo' and 'Marketer', were then inoculated mechanically with different types of inoculum. The success of this process was checked by RT-PCR and agarose gel electrophoresis. After these analyses were concluded, the presence of the viroid was confirmed by sequencing. We inoculated 50 plants of each variety. The results showed that the highest level of infection was achieved when using the RNA-transcript in the positive orientation, where we achieved 100 % infection in both varieties. Plasmid inoculation had a 50 % infection rate, while PCR products had an infection rate of 50 % for 'Suyo' and 40 % for 'Marketer'. RNA-transcript in the negative orientation had 30 % infectivity in both varieties.
|
