On the ecology of Lophodermium piceae, a needle endophyte of Norway spruce

The significance of endophytic needle infections to Norway spruce is still largely unsolved. Lophodermium piceae is the most common species representing typically over 90 % of the cultivable isolates obtained from surface sterilized needles. Generally, more than 50 % of the needles are infected with this species and single healthy looking needles can accommodate several, even more than 30 individual infections, while still looking green and healthy (Müller et al. 2001). The foliage of Norway spruce (Picea abies) is noteworthy resistant against herbivores and diseases in North Europe as compared to needles of Scots pine (Pinus sylvestris). Interestingly, Scots pine needles are not colonized with any single dominating endophyte species similarly as needles of Norway spruce. Therefore, it appears intriguing to find out if resistance of Norway spruce needles against herbivores and diseases is mediated by L. piceae.