Risks of pine wood nematode for Russia
Bursaphelenchus xylophilus (EPPO A1 list), the pine wood nematode, is a quarantine pest for Russia. Although the related non-pathogenic species B. mucronatus occurs in Russia, B. xylophilus has not been recorded. The Russian Plant Protection Service considers that the nematode presents a risk of causing serious mortality in areas where mean July temperature exceeds 25øC. In Russia, this includes only a relatively small area around Astrakhan, northwest of the Caspian Sea. However, the Republics of Turkmenistan, Uzbekistan, Tadzhikistan, Kyrgyzstan, and the southern part of Kazakhstan all fall in this danger zone. ;Slower disease development and reduced mortality can be expected where the mean July temperature is 20-25øC. In Russia, this includes most of the Don and Volga valleys, and a limited area along the Chinese frontier in the Far East. This zone also includes southern Ukraine, and central Kazakhstan. In all the rest of Russia, mean July temperature is less than 20øC and B. xylophilus is not expected to cause any damage, although it could still survive and spread.
The main species said to be at risk are Pinus sylvestris, Pinus koraiensis, Picea abies and Abies balsamea. The greatest risk of introduction by natural vector movement would be in the Far East, but the zones concerned have not yet been systematically surveyed. Some information is available from studies in countries importing wood from that zone. These have confirmed that B. mucronatus occurs. USDA has cited a Chinese report of B. xylophilus in wood from Russia.
The greatest potential impact of B. xylophilus is considered to be the problems its presence in Russia would create for Russian wood exports, rather than its direct effects on Russian forests.
Sources
O.A.Kulinin ; N.V. Kolosova (1993) Zashchita Rastenii, no. 8, 22-24.