My research focuses on diseases in trees and shrubs, specifically on Phytophthora and fungal diseases in nurseries, forests, Christmas tree fields and urban green areas. I am also involved in Christmas tree improvement projects where the goal is to find superior Christmas trees for Norwegian conditions. In 2013, I completed my Master of Science in Forestry at the Swedish University of Agricultural Sciences (SLU). In 2018, I achieved my PhD in Forestry and Environmental Resources at North Carolina State University (NCSU) and SLU. During my PhD, I worked on several projects on Phytophthora and fungal diseases in Christmas tree plantations together with researchers at NIBIO. Since August 2018, I have been working at the Department of Fungal Plant Pathology in Forestry, Agriculture and Horticulture at NIBIO.
Poster – Development of fruiting bodies produced by Neonectria fuckeliana on spruce
Venche Talgø, Martin Pettersson
No abstract has been registered
Lecture – Neonectria canker – a potential threat to production of spruce in Sweden
Martin Pettersson, John Framton, Jonas Rönnberg, ...
NIBIO BOOK 4(4):33-34
Lecture – Neonectria fuckeliana on spruce in Norway
Venche Talgø, Martin Pettersson, May Bente Brurberg, ...
NIBIO BOOK 4(4):30-32
The fungus Neonectria fuckeliana has become an increasing problem on Norway spruce (Picea abies) in the Nordic countries during recent years. Canker wounds caused by the pathogen reduce timber quality and top-dieback is a problem for the Christmas tree industry. In this study, four inoculation trials were conducted to examine the ability of N. fuckeliana to cause disease on young Norway spruce plants and determine how different wound types would affect the occurrence and severity of the disease. Symptom development after 8–11 months was mainly mild and lesion lengths under bark were generally minor. However, N. fuckeliana could still be reisolated and/or molecularly detected. Slow disease development is in line with older studies describing N. fuckeliana as a weak pathogen. However, the results do not explain the serious increased damage by N. fuckeliana registered in Nordic forests and Christmas tree plantations. Potential management implications, such as shearing Christmas trees during periods of low inoculum pressure, cleaning secateurs between trees, and removal and burning of diseased branches and trees to avoid inoculum transfer and to keep disease pressure low, are based on experiments presented here and experiences with related pathogens.
Phytophthora cryptogea, P. gonapodyides, P. lacustris, P. megasperma, P. plurivora, P. taxon paludosa and an unknown Phytophthora species were isolated from waterways and soil samples in Christmas tree fields in southern Sweden. In addition, P. megasperma was isolated from a diseased Norway spruce (Picea abies) plant from one of the fields in Svalöv. Inoculation tests were sequentially carried out with one isolate from each of the three species P. cryptogea, P. megasperma, and P. plurivora, all known pathogens on conifers. The same three isolates were used to study a few morphological features to confirm the identification, and temperature-growth relationships were carried out to see how well the organisms fit into Swedish climatic conditions. Seedlings of Norway spruce and Nordmann fir (Abies nordmanniana) were inoculated in the roots and the stems. None of the isolates caused extensive root rot under the experimental conditions, but all three species could be re-isolated from both Norway spruce and Nordmann fir. Phytophthora root rot is currently of minor concern for Christmas tree growers in Sweden. However, the Phytophthora isolations from soil and water indicate the presence of this damaging agent, which may lead to future problems.