Influence of the endophyte (Neotyphodium lolii) on morphology, physiology, and alkaloid synthesis of perennial ryegrass during high temperature and water stress

Abstract

The influence of the endophyte (Neotyphodium lolii) on morphology and physiology of perennial ryegrass (Lolium perenne) ’Grasslands Nui’ was examined in a replicated glasshouse experiment. Ryegrass plants either free of endophyte or infected with its endemic endophyte (wildtype) or AR6 (low lolitrem B‐producing endophyte strain) were grown under combinations of water (well watered versus water stressed) and temperature (25°C (hot) average versus 20°C (low) average) treatments. Endophyte‐free plants had significantly higher shoot and total weight, higher water use and water use efficiency, and were more wilted than endophyte‐infected plants. There was a significant (P < 0.05) endophyte × temperature interaction and endophyte × temperature × water interaction for lolitrem B concentration and wilt score, and the endophyte × water interaction was significant (P < 0.05) for ergovaline concentration and wilt score.