Browsing by Author "Pennanen, Laura"

The potato virus Y (PVY) is a type member of the family Potyvirus which infects the nightshade family (Solanaceae) plants. Economically it is considered to be the most siqnificant problem in seed potato production worldwide. Meaningful methods to prevent economical damage caused by PVY are the production of certified seed potato and breeding of PVY-resistant cultivars. The starting point of breeding is identifying different PVY strains. Sequence information from HCPro protein (HCPro) and coat protein (CP) regions are essential to be able to identify different PVY strains and their recombinant forms. The aim of this study was to express the variation in CP and HCPro regions of PVY. This was done by sequencing PVY data from Finlands seed potato fields from year 2015 and comparing it to Yanping Tians (Doctor of Science, Agriculture and Forestry) sequence data from the same area from the years 2006 and 2007. The PVY positive samples used in this study were collected in 2015 in a virus screening test executed by Evira. The screening was done by using ELISA test. The comparison in this study was executed by aligning CP and HCPro regions from all samples and examining the regions by nucleotide and aminoacid level. Comparison was also executed by creating phylogenetic trees from aligned sequences. On the findings of this study the recombinant strain PVY-NTN was the most common strain in Finlands seed potato fields in 2015. Occurence of PVY-O strain was reduced significantly when compared to data from 2006 and 2007. The seven PVY-NTN samples that were examined in this study had a typical aminoacid region to PVY-O strain. This region covers aminoacids R269–K270 and is absent from a known recombinant PVY-NTN ”Nevski” and it is also a singular finding when compared to Yangping Tians samples. However, this change in aminoacid structure did not seem to provoke resistant genes in known potato cultivars to recognize these samples. It is plausible that PVY profits from this new mutation in its aminoacid structure, but this cannot be point out on the bases of this study.