Assessment of species distributions in Pleurotus based on trapping of airborne basidiospores

Abstract

A species-specific spore trapping method was employed to detect different species of the oyster mushroom genus Pleurotus from different geographic regions. Monokaryotic tester strains representing five intersterility groups in the P. ostreatus complex were used as spore trap baits. Colonies of each strain were exposed to the outside environment from 24 to 48 hours. Afterward, explants taken from the plates were transferred to fresh media and observed for evidence of dikaryotization. Sets of petri dishes containing all five species were distributed by mail to mycologists at diverse locations in the Northern Hemisphere, where they were placed out for sampling and later returned by mail for scoring. In spite of a relatively high level of contamination, dikaryotization was observed for all five species. The results suggest that spore trapping in this manner can be an effective method for sampling genetic diversity over broad geographic areas.

Key Words:

• dispersal
• intersterility groups
• mating compatibility
• Pleurotus cornucopiae
• Pleurotus djamor
• Pleurotus ostreatus
• Pleurotus populinus
• Pleurotus pulmonarius