Ergovaline concentration in perennial ryegrass infected with a lolitrem B‐free fungal endophyte in north‐west Spain

Abstract Ergovaline concentrations in two perennial ryegrass genotypes (EI 19 and EI24) infected with one lolitrem B‐free fungal endophyte were determined over a 3‐year period at two different locations in north‐west Spain. There was a significant sampling date effect over 3 years and two locations (P < 0.05). The mean ergovaline concentrations ranged from 0.06 ppm in early spring to 0.57 ppm in June. EI19 genotype had significantly (P < 0.05) higher ergovaline concentrations (0.37 ppm, SE = 0.09) than EI24 genotype (0.33 ppm, SE = 0.08) only at one location in year 2000. Under north‐west Spanish conditions, ergovaline levels obtained in this study were not so high to reach values potentially toxic for animals. The results presented in this paper suggest that agriculturally useful ryegrass endophyte associations can be developed free from lolitrem B, and which do not accumulate excessive concentrations of ergovaline.