Trigonelline accumulation in leaves of Panicum virgatum seedlings

Panicum virgatum is a dominant, native, perennial species found in the tallgrass prairie. In this study, we report the biosynthesis and accumulation of trigonelline (TRG) in leaves of P. virgatum in response to water-deficit stress. Once established, half of the seedlings underwent a drought stress treatment while the other half were watered daily (control). Relative water content (RWC) and trigonelline (TRG) concentrations were determined. RWC showed an interaction between moisture treatment and time, in which upland cultivars had the highest mean RWC compared with the lowland cultivars. The moisture treatments showed a significant difference in TRG concentration across all P. virgatum cultivars, which ranged from 0.5-31.8 microg/gFW(-1). There was a divergence in TRG accumulation between upland and lowland cultivars in relation to RWC. This study is the first to report TRG accumulation in the grass P. virgatum, and to test for differences in TRG with respect to water-deficit stress among cultivars. The effect of soil moisture levels on cultivars may be important in making an informed selection and the response of P. virgatum and other dominant grasses should be considered as a potential filter in tallgrass prairies for restoration. Physiological markers such as TRG and RWC can aid in this decision making process.