Förekomst av törskate (Cronartium flaccidum, Peridermium pini) på tall (Pinus sylvestris) i relation till markfuktighet och fältskikt
en studie om 2000-talets törskateepidemi i norra Sverige
Resin-top disease is a rust fungi that occurs both as a host alternating form, Cronartium flaccidum G. Winter., and as a non-host alternating form, Peridermium pini Pers. The host alternating form can use a variety of hosts but the most commonly used species in the boreal forest is Melampyrum sylvaticum. In Scandinavia the Resin-top disease infect Scots pine, Pinus sylvestris L. The fungus infects the needles through the stomata and then grows through the branch to the stem where it strangulates the vessels transporting water and nutrition to the treetop, which kills the top. During the 21st century severe damages caused by Resin-top disease was reported in Västerbotten and Norrbotten. This caused The Swedish National Forest Inventory to execute a national damage monitoring in 2007 and 2008. We investigated if the presence and frequency of Resin-top disease increased with better ground cover vegetation (indicating better productivity) and more moist soils, and how a combination of these two site factors affected the presence and frequency. Our results showed that Resin-top disease was more abundant with more severe damages on sites indicating better ground cover vegetation. The soil moisture had no significant effect on neither the abundance nor the damage frequency of Resin-top disease. Mesic productive (fertile) sites had more severe damages than sites with lesser productivity and lower soil moisture.