Current issue: 53(4)
Infection of living Norway spruce (Picea abies (L.) H. Karst.) trees by bacteria, and the properties of these bacteria were studied. Bacterial antagonism to three decay fungi was also studied in laboratory conditions.
Bacteria could be found in 26% of all spruce injuries. Bacterial infection was most frequent in injuries made in March–April and June, and least frequent in December–February. Bacteria infected most often sapwood injuries in roots above soil level, 55% of the bacterial colonies were isolated from these injuries. 27% of the colonies were isolated from injuries made by increment borer at breast height, extending to heartwood, 16% from sapwood injuries at breast height, and 2% from injuries at stump height. The main bacterial groups were gram-positive rods (55%) and gram-negative rods (29%).
In 65% of the bacteria the metabolism was fermentative, in 14% slowly fermentative, in 7% oxidative, in 8% slowly oxidative, and in 6% alkalizing. 19% utilized cellulose, 15% in the presence of organic, 3% in the presence of inorganic nitrogen.
One bacterial strain was the only micro-organism growing in the injury a year after the damage, although the injury had been infected with Peniophora gigantea (Phlebiopsis gigantea). In laboratory experiments, this rod bacterium, gram-negative strain proved to be antagonistic to Fomes annosus (Heterobasidion annosum), Stereum sanguinolentum and P. gigantea. It had no capacity for cellulose utilization.
The PDF includes a summary in Finnish.