Seed germination is pivotal in the life cycle of native plants in a restorative context because initiation of the metabolic processes critical to establishment is key to survival in such a competitive environment. Dormancy characteristics of some native plants including the subject species, Astragalus utahensis, have evolved mechanisms to control germination in order to maintain a seed bank and ensure germination at the right time under optimal conditions. In vitro germination studies confirm beneficial interactions between Alternaria and Aspergillus fungi and Astragalus utahensis seed. Inoculated seed trials (1.0 x 106 spores/mL) exhibited a highly significant difference in percent germination between the uninoculated control at 5.0 % germination and seeds inoculated with Alternaria and Aspergillus germinating at 95 % and 55 %, respectively. Germination trials conducted in the greenhouse revealed a beneficial relationship between fungal spore inoculation and seed germination. Control seeds germinated in soil at a rate of 16.0 %; three times as high as exhibited in vitro. Seed inoculated with either Alternaria or Aspergillus seeds germinated in soil at the same rate of 50.0 %. A seed germination trial conducted in the field demonstrated a beneficial response with Aspergillus inoculation. Fall plantings on two sites near Fountain Green and Nephi, Utah confirm this beneficial response to Aspergillus spore inoculation. These field trials indicated a highly significant response with the germination of scarified control seed at 14.7 % and the Aspergillus and Alternaria treated seed germinating at 29.3 and 19.3 %, respectively. Greenhouse germination trials with spore-inoculated seed indicated a 100% survival rate. Astragalus utahensis seeds germinated at an accelerated rate when inoculated with Aspergillus and Alternaria spores in-vitro. The beneficial germination response of fungal inoculated seeds indicates the efficacy of these treatments in dormancy contravention in hard-seeded species.
College and Department
Life Sciences; Plant and Wildlife Sciences
BYU ScholarsArchive Citation
Eldredge, Sean D., "Beneficial Fungal Interactions Resulting in Accelerated Germination of Astragalus utahensis, a Hard-Seeded Legume" (2007). All Theses and Dissertations. 1231.
Alternaria, Aspergillus, Astragalus utahensis, seed, accelerated, germination, inoculation, field, mechanisms, restoration, disturbance