ABSTRACT
Ericoid mycorrhizas may have been traced in the roots of all Ericoid plants, but not necessarily all year round. Cairney and Ashford (2002) believe that ericoid mycorrhizas, particularly those colonizing the eparcids in Australia, are strongly seasonal. Loss of hair roots, along with the mycorrhizal fungal component, seems common in dry season or drought-affected plants. Hair roots reappear in autumn and their length increases with soil moisture. These roots become mycorrhizal, and the highest colonization rates are around spring time. Studies utilizing ITS sequence analysis indicate that in the Northern Hemisphere, ericoid mycorrhizas persist throughout the year (Read and Kearley, 1995), except in dry years. Within limits, the Ericoid mycorrhizal distribution may not be affected much by the latitude, altitude, edaphic or climatic parameters (Read, 1996). Location-specific effects are equally important. For example, in W. pungens grown in Australia, the mycorrhizal infection may not be correlated with minor changes in moisture, but was negatively correlated with temperature.
