Abstract:

Pine shoot blight disease(Sphaeropsis sapinea) was a pine disease that took place around the world.It mainly infected Pinus taeda, P.elliottii,P.echinata and P.massoniana in China. This study showed the pine shoot blight fungus could be isolated from the healthy tissues of the four pines in each month yearly.The isolated fungus percentages were associated with 15%～37.7% of P.taeda,13.8%～57.1% of P.echinata,7.5%～29.1% of P.elliottii and 9.7%～22.4% of P.massoniana. There were some percentage differences in different parts of pine individuals,higher on branches and shoots,a little lower on buds,and the lowest on the needles.Asymptomatic shoots and buds were cultured on damp filter paper.After 10 days,pycnidias of S.sapinea could be found on the segments.The results were similar with those used isolation methods.Before the current-year spores were released,some shoots and buds of pine were covered with blastic bags.Some of shoot blight and bud rot appeared.All as above,it was sure that there existed latent infection of S.sapinea on pine.

Key words: Sphaeropsis sapinea, Latent infection, Pinus taeda, P.elliottii, P.echinata, P.massoniana