Browsing by Subject "symbiotic fungi"

This thesis discusses the concept of mycorrhization in the roots of land plants, their reliance on symbiotic fungi and the diversity of these relationships. Specifically, the focus of this study is the mycorrhization of ericaceous plants in boreal forest ecosystems and the role this plays in aiding host survival of harsh conditions. This study presents the first comparison of the colonization patterns of both fungal and bacterial consortia in the roots and mycospheres of different boreal forest ericoid species. Experimentally, the mycorrhizal fungal and bacterial communities of roots of the Ericaceous species Vaccinium myrtillus, Vaccinium vitis-idaea, and Calluna vulgaris were characterized and quantified. To simulate natural conditions, the host species were grown in forest soil microcosms under controlled conditions with mycorrhization occurring naturally. The morphology and intensity of root colonization by ericoid mycorrhizal fungi was determined through light microscopy. Quantification of fungal and bacterial abundances was performed using quantitative Polymerase Chain Reaction for the roots and soil of each species. Microscopic analysis revealed differences in both morphology and intensity of ericoid mycorrhization for the species studied. The fungal and bacterial abundances for the roots of each host species were found to be significantly different, while the soil abundances of each species showed considerable variation and were not found to be significantly different. An intriguing connection between the fungal and bacterial abundances colonizing the root systems of the different plant species was indicated by comparison. These findings begin to clarify the unique relationships each ericoid species has with the highly diverse fungi and bacteria of their environment. Further refinement of techniques and more in depth analyses are suggested for confirming the differences indicated by these results. The ecological significance of such work is also discussed in regards to fully understanding forest ecosystems as well as the potential for novel discoveries that may benefit many aspects of humanity.