| Diplodia tip blight | |
|---|---|
 Red pine (Pinus resinosa) with bark removed to show dark wood staining caused by Diplodia tip blight | |
| Common names | dieback of pine shoot blight of conifers shoot dieback of conifers tip blight of conifers twig blight of conifers whorl canker of pine |
| Causal agents | Diplodia sapinea |
| Hosts | pine trees |
| EPPO Code | DIPDPI |
| Distribution | United States |
Diplodia tip blight, also known as Sphaeropsis blight, is a widespread disease affecting conifers caused by an opportunistic fungal pathogen, Diplodia sapinea. It is found in “both hemispheres between the latitudes 30° and 50° north and south".[1] The diseases symptoms include: damping off and collar rot of seedlings, stem canker, root disease, and, most commonly, shoot blight. These symptoms have caused significant economic loss to nurseries and pine plantations. In a nursery in the north-central United States, losses of 35% have been reported.[1] Shoot blight and eventual die back can cause a reduction of marketable volume in timber by 63%.[1] Infection of terminal shoots can result in dead-top which significantly limits the usable length of the tree trunk.[1] The presence of the pathogen in concert with severe weather conditions can lead to extreme loss. Following a severe hailstorm in South Africa, nearly 5,000 acres of pine plantation were infected with Diplodia tip blight. It was necessary to prematurely harvest large swaths of the plantations resulting in a loss of 45%. Areas that were not harvested prematurely still suffered an average timber loss of 11%.[2]
- ^ a b c d Swart, W.J. (1991). "Biology and control of Sphaeropsis sapinea on Pinus species in South Africa". Plant Disease. 75 (8): 761–766. doi:10.1094/PD-75-0761.
- ^ Zwolinski, J. B.; Swart, W. J.; Wingfield, M. J. (1990-12-01). "Economic impact of a post-hail outbreak of dieback induced by Sphaeropsis sapinea". European Journal of Forest Pathology. 20 (6–7): 405–411. doi:10.1111/j.1439-0329.1990.tb01155.x. ISSN 1439-0329. S2CID 85072546.