Endophyte infection can contribute to aluminum tolerance in fine fescues

Thirteen clonal pairs of endophyte-free and endophyte-infected fine rescues were evaluated in a growth chamber study for growth in three sand-soil formulations differing in available aluminum. This set of plants consisted of four Chewings rescue [Festuca rubra L. subsp. fallax (Thuill) Nyman] and two strong creeping red rescue (Festuca rubra L. subsp. rubra) genotypes inoculated with endophytes originating from Chewings fescue, strong creeping red fescue, and Poa ampla Merr. hosts. The results revealed a considerable endophyte-host interaction on plant growth in the different soils. In most cases, the effect of endophyte infection on dry weight was either positive or neutral. In a few cases, endophyte infection had a negative effect on dry weight. In some endophyte-host combinations, the endophyte-infected clone had significantly better growth in the high aluminum soils relative to the endophyte-free clone. These results indicate that endophyte infection alone is not enough to confer aluminum tolerance in fine fescues, but in certain plant-fungus combinations, endophyte infection can contribute to enhanced aluminum tolerance.