AR37 endophyte effects on porina and root aphid populations and ryegrass damage in the field

Abstract

The novel endophyte, AR37, in ryegrass has reduced porina larval survival and plant damage in pot trials. To determine the effect of AR37 on larvae in the field, populations were estimated in two ryegrass field trials in Canterbury. Plant damage and plant densities were also scored in one trial. At Ceres Farm, no porina were found in Italian ryegrass 'Status' infected with AR37 whereas low populations (

Temperature and Plant Genotype Alter Alkaloid Concentrations in Ryegrass Infected with an Epichloë Endophyte and This Affects an Insect Herbivore

“…The endophyte AR37 is very important for the control of porina in New Zealand as although other endophytes such as AR1 and the common toxic strain provide protection against some pest insects ( Prestidge et al, 1982 ; Popay et al, 1999 ; Pennell et al, 2005 ; Popay and Gerard, 2007 ; Popay and Thom, 2009 ) it is only AR37 which provides ryegrass with protection against porina ( Jensen and Popay, 2004 ; Popay et al, 2012 ). Control against porina, which are a major pasture pest in parts of New Zealand, currently involves an integrated pest management strategy involving planting ryegrass infected with the AR37 endophyte and the application of insecticides at particular times of the year ( Barratt et al, 1990 ).…”

“…The endophyte gains from its host shelter, nutrients and a means of transmission ( Saikkonen et al, 2004 ). In return the plant gains increased protection from biotic stresses including insects ( Prestidge et al, 1982 ; Ball and Prestidge, 1992 ; Pennell et al, 2005 ; Popay et al, 2012 ), mammalian herbivores ( Edwards et al, 1993 ; Cosgrove et al, 2002 ), pathogens ( Pańka et al, 2013 ) and nematodes ( Eerens et al, 1997 ; Bacetty et al, 2009 ) as well as increased tolerance to abiotic stresses such as drought and nutrient stress ( Ravel et al, 1997 ; Kane, 2011 ; Nagabhyru et al, 2013 ).…”

“…Larvae can be highly destructive as they feed by cutting ryegrass tillers off at the base of the plant or by grabbing low lying leaves before dragging the herbage back into their burrow ( Harris, 1969 ). The ‘selected’ endophyte AR37 has been shown to provide ryegrass with resistance against porina larvae in pot trials ( Jensen and Popay, 2004 ), choice bioassays ( Jensen and Popay, 2004 ) and field trials ( Popay et al, 2012 ). In addition, when pure and semi-pure epoxy-janthitrem I, produced by AR37, was incorporated into a semi-synthetic diet and fed to porina larvae, larval diet consumption and growth were significantly reduced ( Finch et al, 2010 ; Hennessy, 2015 ).…”

Quantifying the economic cost of invertebrate pests to New Zealand’s pastoral industry

“…The ryegrass endophyte AR37 deters porina and is available in a range of cultivars. Swards of AR37-infected ryegrasses have been shown to support fewer porina than their uninfected equivalents (Popay et al 2012) and to persist in the presence of populations of porina exceeding 200/m 2 (Ferguson unpublished). In porina-prone areas, economic benefit can be achieved by using AR37-infected ryegrasses, despite a small increase in seed cost (about $3.00/kg).…”

Identification and Structure Elucidation of Epoxyjanthitrems from Lolium perenne Infected with the Endophytic Fungus Epichloë festucae var. lolii and Determination of the Tremorgenic and Anti-Insect Activity of Epoxyjanthitrem I

“…Another commercial endophyte, AR37, shows much broader effects against common insect pasture pests. Although not producing peramine and thus being ineffective against adult Argentine stem weevil, AR37 has a strong effect on reducing Argentine stem weevil larval damage [10], has an effect on adult African black beetle [11] as well as effects on porina (Wiseana cervinata) [12,13], root aphid [11,14,15] and pasture mealybug (Balanococcus poae) [16]. The AR37 endophyte in perennial ryegrass does not express lolitrem B but does induce ryegrass staggers, although episodes recorded in animals grazing AR37 are less frequent and less severe than those observed in animals grazing naturally-occurring, common-toxic endophyte pastures [17].…”