Effect of <i>Epichlo</i> endophyte strains in <i>Lolium</i> spp cultivars on Argentine stem weevil parasitism by <i>Microctonus hyperodae</i>

Abstract

This paper reports on an extensive field investigation conducted at Lincoln during the 20142015 summer/early autumn This aimed to assess the effects of a range of novel Epichlo endophytes when present in different cultivars of Lolium spp on parasitism rates by the biological control agent Microctonus hyperodae in Listronotus bonariensis (ie the Argentine stem weevil) Results for the entire summer and including all treatment combinations did not find any significant differences in parasitism in L bonariensis populations However in the early autumn independent of the endophytes present significantly higher levels of parasitism were found in a tetraploid Lolium multiflorum cultivar and a tetraploid L perenne selection compared to the L perenne cultivars Whether this finding has any bearing on a possible mechanism of weevil resistance is discussed