Cytospora kunzei on plantation-grown Pinus elderica in Turkey

Abstract.

Cytospora kunzei was detected on Pinus elderica at the plantation of Besni-Beskoz in Adiyaman, Turkey between 1999 and 2002. This is the first record of C. kunzei on P. elderica. Infections were evident on a number of trees when first detected in the beginning of April 1999, but rapidly increased during spring and early summer throughout 1999 and 2000. After 2001, disease development began to decrease, and many moderately and slightly infected trees recovered from this infection by producing healthy young shoots. However, disease development continued on some trees during 2001 and 2002. The percentage of infected trees was 40.1% in 1999, 63.2% in 2000 and 7.9% in 2001; disease severity was 7.5% in 1999 and 15.4% in 2000. No tree mortality occurred during 1999, but 0.6% of the trees were killed in the second year. Disease development, based on infection rates at four different intervals was r ² = 0.999 in 1999 and r ² =0.944 in 2000. C. kunzei was isolated from tissue adjacent to cankers on diseased trees and inoculation tests indicated that trees were more predisposed to canker development in 1999 and 2000 compared with 2001. Low rainfall, high temperature and their combined effect during 1999 and 2000 were probably the main stresses predisposing the trees to this pathogen and favouring the development of this epidemic.