9808554 Schardl The defenses of plants against insects include diverse nitrogen-containing chemicals called alkaloids. In grasses that possess symbiotic fungal endophytes several important anti-insect alkaloids are produced by the endophytes, which thereby protect the grass plants from herbivorous insects. This project focuses on the lolines, fungal alkaloids that are unique to grass-endophyte systems, highly insecticidal, and exceptionally abundant. building on the finding that the endophyte is the source of lolines, the biochemistry and genetics of loline alkaloid production will be conducted. First, culture methods will be refined to induce or suppress fungal expression of lolines. Making use of these methods, the specific fate of proposed loline alkaloid precursors will be determined. Finally, genes that may code for steps in the biosynthetic pathway to lolines will be identified based on differences in expression under loline alkaloid-expressing and non-expressing conditions. This work will advance understanding of the biosynthesis of secondary metabolites that play important roles in biological protection of plants from their pests, and in ecological interactions between plants and beneficial microorganisms. A likely applied benefit to society will be more informed and widespread use of biological plant protection systems in agriculture and horticulture, helping reduce the use of ecologically damaging chemicals and practices.
