Incidence and pathogenicity of Phytophthora palmivora and Pythium vexans associated with durian decline in far northern Queensland.

摘要

In recent years, dieback of durian has become a major problem in mature orchards in the wet tropics region of northern Queensland, Australia. A survey of 13 durian orchards was conducted during the dry season (July-September 2001) and following wet season (February-April 2002), by sampling the roots and soil from the root zone of affected trees. Phytophthora palmivora was recovered from the roots of the affected trees on 12 of the 13 farms during the dry season, and all farms during the wet season. Pythium vexans was recovered from all 13 farms in both seasons. P. palmivora and P. vexans were recovered from diseased roots of 3-month-old durian seedlings cv. Monthong artificially inoculated with these organisms.