Germination, Establishment and Mycorrhizal Synthesis in the Epacrid Woollsia pungens

Woollsia_-/+mycorrhiza

Summary of final report on the Australian Flora Foundation funded project:

Anne E Ashford & John H Palmer
School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW 2052, Australia.
Grant Details    Final Report

Seeds of known provenance of Woollsia pungens (Cav.) F. Muell. were collected from a large population growing in the Georges River National Park on two different years and subjected to germination trials, with emergence of the radicle as the measure of successful germination. No dormancy was apparent and we found no specific effects of photoperiod, light intensity, temperature or smoke on percentage germination. We have found that W. pungens has a distinct juvenile stage and that there is a transition from this to the adult stage when the seedlings are 12-18 months old. This transition is accompanied by a change in leaf shape. Calcium hypochlorite was found to be an effective surface sterilizing agent for the seed and an axenic culture system was established to grow seedlings and inoculate them with an appropriate mycorrhiza-forming fungus and follow whether mycorrhizal synthesis had occurred and whether it had been beneficial to plant growth. Using this system we inoculated boxes containing seedlings with the endophyte MG60 that had been isolated from Woollsia pungens in the wild. We found that plants in boxes that had been inoculated with MG60 developed mycorrhizas. Plants in the boxes that had been inoculated were more vigorous than those in boxes that had not.