title: Epichloë uncinata Infection and Loline Content Protect Festulolium Grasses From Crickets (Orthoptera: Gryllidae).
abstract: Experiments with artificial diets demonstrated that black field cricket (Teleogryllus commodus (Walker)) and Lepidogryllus sp. were highly responsive to presence of lolines in their diet-quantities of diet consumed declined exponentially with increasing loline concentration. Amount consumed by black field cricket and Lepidogryllus sp. on diet containing 5,600 µg/g lolines was only 8 and 2% relative to those on loline-free diet, respectively. Additional experiments with Festulolium seeds demonstrated that both cricket species predated heavily on endophyte-free seed but largely avoided Epichloë uncinata-infected seed. By 12 h, black field cricket had destroyed 98.8% of endophyte-free but only 24.8% of E. uncinata-infected, loline-containing seed. By 36 h, Lepidogryllus sp. crickets had destroyed 40% of endophyte-free but had not fed on E. uncinata-infected, loline-containing seed. Glasshouse experiments demonstrated this aversion to lolines greatly reduces the damage potential of black field cricket in E. uncinata-infected Festulolium. When microswards were sown with E. uncinata-infected Festulolium, seedling numbers were reduced 25-26%, and yields 29-40%, by black field crickets relative to microswards sown without insect infestation. This contrasts with 70-78% reduction in seedling numbers and 67-80% reduction in yields in microswards sown to either endophyte-free Festulolium, endophyte-free perennial ryegrass, or Epichloë festucae var. lolii-infected Festulolium. Yields of mature E. uncinata-infected Festulolium plants were not adversely affected by black field crickets, irrespective of the presence of the endophyte-free standard Festulolium sown as a companion. In contrast, yields of endophyte-free Festulolium, endophyte-free perennial ryegrass, and E. festucae var. lolii-infected Festulolium plants were reduced by 56-61% by crickets.
authors.affiliation: Research Associate, Landcare Research, Private Bag 3127, Hamilton, New Zealand. 125 Charltons Road, Stony Creek, Victoria 3957, Australia. Corresponding author, e-mail: barkerg@landcareresearch.co.nz.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Barker
authors.affiliation: Cropmark Seeds, PO Box 16-574, Templeton, Christchurch 8441, New Zealand.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Patchett
authors.affiliation: Cropmark Seeds, PO Box 16-574, Templeton, Christchurch 8441, New Zealand.
authors.forename: Nicholas E
authors.initials: NE
authors.lastname: Cameron
mesh_terms: D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D060026:Endophytes; D055329:Epichloe; D005247:Feeding Behavior / Q000187:drug effects; D006135:Gryllidae; D060434:Herbivory; D006109:Poaceae / Q000382:microbiology*
chemical_list: D000470:Alkaloids; C059478:loline
keywords: fungal endophyte; meadow fescue; pest resistance; plant protection; ryegrass