Endophyte Infection Rate and Alkaloid Concentrations in Seeds of Commercial Cultivars of Perennial Ryegrass

Abstract

Perennial ryegrass (Lolium perenne L.) is used for not only forage but also turf. Recently, since many turf-type cultivars that are artificially infected with endophyte have been marketed, seeds of those cultivars could be sown in grasslands. To compare varietal characteristics of poten- tial endophyte toxicosis, endophyte infection rate and ergovaline and lolitrem B concentrations as alkaloid were investigated for seeds of 28 commercial cultivars of perennial ryegrass. The cultivars consisted of 5 forage-type and 23 turf-type. Endophyte infection rate and ergovaline and lolitrem B concentrations varied among 28 cultivars in the range of 0-96%, 0.0-2.8ppm, 0.0-6.5ppm, respectively. In endophyte infection rate, the cultivars could be roughly divided into two groups, one with the higher value of above 60%, and the other with the lower value of below 20%. All of cultivars in the high-rate group were turf-type and had higher ergovaline and lolitrem B concentrations. On the other hand, any cultivars in the low-rate group did not have ergovaline and lolitrem B. All of forage-type cultivars had 0% of endophyte infection rate and did not have ergovaline and lolitrem B.