Name
Potential of two partitiviruses in the biocontrol of fungal forest pathogen Heterobasidion annosum
Presenter
Elina Roininen, University of Helsinki
Co-Author(s)
Elina Roininen1,2, Suvi Sutela2, Anna Poimala2, Muhammad Kashif2, Aku Korhonen2, Leena Hamberg2, Rajendra Ghimire2, Eeva Terhonen2, Minna Kivimäenpää2, Tuula Piri2, Eeva J. Vainio2, Minna Poranen1 and Jarkko Hantula2
1.Faculty of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1, Helsinki FI-00790, Finland
2.Natural Resources Institute Finland (Luke), Latokartanonkaari 9, Helsinki FI-00790, Finland
Abstract Category
Combatting and Exploiting dsRNA viruses
Abstract
Heterobasidion root rot, caused by Heterobasidion parviporum and H. annosum, is a widespread, economically significant disease affecting mainly Picea and Pinus. These fungi host diverse dsRNA mycoviruses that may influence the fungal virulence, and thus have potential for Heterobasidon biocontrol. Previous studies have shown that alphapartitiviruses HetPV13-an1 and HetPV15-pa1 reduce the growth of many H. parviporum and some H. annosum strains, but the effect of HetPV13-an1 and HetPV15-pa1 coinfection has been investigated previously only with one H. annosum strain.
We analyzed the transmission frequencies of HetPV13-an1 and HetPV15-pa1 from donor to recipient fungus together and separately. In addition, we investigated the impact of partitivirus infections on the growth of several Finnish H. annosum strains in vitro, in billet, and in living trees. We found that transmission efficacy was overall high, and that coinfection did not enhance it. All the tested H. annosum strains tolerated well the partitivirus infections when grown in vitro or in dead wood. However, experiments in living trees revealed high variation in the virus induced growth effects. In addition, we currently investigate the regulation of heterokaryon incompatibility by partitiviruses and how this mediates virus spread. In conclusion, our findings suggest that HetPV13-an1 and HetPV15-pa1 show limited potential in controlling H. annosum under natural conditions.
We analyzed the transmission frequencies of HetPV13-an1 and HetPV15-pa1 from donor to recipient fungus together and separately. In addition, we investigated the impact of partitivirus infections on the growth of several Finnish H. annosum strains in vitro, in billet, and in living trees. We found that transmission efficacy was overall high, and that coinfection did not enhance it. All the tested H. annosum strains tolerated well the partitivirus infections when grown in vitro or in dead wood. However, experiments in living trees revealed high variation in the virus induced growth effects. In addition, we currently investigate the regulation of heterokaryon incompatibility by partitiviruses and how this mediates virus spread. In conclusion, our findings suggest that HetPV13-an1 and HetPV15-pa1 show limited potential in controlling H. annosum under natural conditions.