Epichloë uncinata infection and loline content afford Festulolium grasses protection from black beetle (Heteronychus arator)

Abstract

The potential of loline-containing Epichloë uncinata-infected Festulolium to resist herbivory by black beetle was examined. We tested the hypothesis that concentration of lolines is pivotal to plant protection. A series of non-choice assays were performed, with excised roots and whole plants offered to larvae, artificial diets offered to adult and larvae, and seedling plants offered to adults. Feeding and live-weight gain of larvae were negatively related to loline concentration in the offered food. Assays with whole potted plants and seedlings showed that the presence of lolines afforded plant protection. Replicated and non-replicated field trials showed population densities of black beetle in plots sown to E. uncinata-infected, loline-containing plant genotypes were generally similar to a genotype infected with Epichloë festucae var. lolii wild type strain, but lower than an endophyte-free genotype and genotypes infected with E. festucae var. lolii strains AR1 and AR37. The results are discussed in relation to plant breeding objectives.