The potential of a New Zealand strain of <i>Phasmarhabditis hermaphrodita</i> for biological control of slugs

Abstract

In New Zealand the European invasive slug Deroceras reticulatum is a pest in home gardens horticulture pastoral and arable agriculture At present there are no biological control options available in New Zealand unlike Europe where the nematode parasite Phasmarhabditis hermaphrodita is sold in several countries under the trade name Nemaslug This paper describes the finding of a nematode parasitising D reticulatum in New Zealand that was identified by morphological and molecular (18S rDNA sequencing) methods as P hermaphrodita The nematode was reared on slug cadavers and shown to infect and kill fieldcollected D reticulatum In mesocosm experiments with clover the New Zealand P hermaphrodita applied at the recommended commercial rate substantially increased plant density even under high slug pressure

Development ofPhasmarhabditis hermaphrodita(and members of thePhasmarhabditisgenus) as new genetic model nematodes to study the genetic basis of parasitism

“…Phasmarhabditis species have been isolated from slugs from around the world including the U.K. (Wilson et al, 1993; this study), Germany (Schneider, 1859;Mengert, 1953), France (Coupland, 1995;Maupas, 1900), Iran (Karimi et al, 2003), Egypt (Azzam, 2003;Genena et al, 2011), Norway (Ross et al, 2015), Chile (France & Gerding, 2000), New Zealand (Wilson et al, 2012), South Africa (Ross et al, 2012;Pieterse et al, 2017a,b). China (Huang et al, 2015), Japan (Waki, 2017), Italy (Nermut et al, 2016a), Czechoslovakia (Nermut et al, 2010;2016b,c) and P.…”

“…The genus Phasmarhabditis contains 11 species: P. hermaphrodita , P. apuliae , P. papillosa , P. neopapillosa , P. valida , P. nidrosiensis , P. californica , P. tawfiki , P. bonaquaense , P. bohemica and P. huizhouensis (Andrássy, 1983; Hooper et al , 1999; Azzam, 2003; Tandingan De Ley et al , 2014, 2016; Huang et al , 2015; Nermut et al , 2016a, b, 2017). Phasmarhabditis hermaphrodita and other Phasmarhabditis species have been isolated from slugs from around the world, including the UK (Wilson et al , 1993; this study), Germany (Schneider, 1859; Mengert, 1953), France (Maupas, 1900; Coupland, 1995), Iran (Karimi et al , 2003), Egypt (Azzam, 2003; Genena et al , 2011), Norway (Ross et al , 2016), Chile (France & Gerding, 2000), New Zealand (Wilson et al , 2012), South Africa (Ross et al , 2012; Pieterse et al , 2017a, b), China (Huang et al , 2015), Japan (Waki, 2017), Italy (Nermut et al , 2016a) and the Czech Republic (Nermut et al , 2010, 2016b, 2017), and P. californica has been found in the USA (Tandingan De Ley et al , 2016), Ireland (Carnaghi et al , 2017) and Wales (this study). From these studies it is apparent that members of the Phasmarhabditis genus have a cosmopolitan distribution and are very easy to isolate from gastropod hosts.…”

“…The majority of research on P. hermaphrodita has focused on optimizing application techniques in the field (see Rae et al , 2007), host range studies (Wilson et al , 1993; Grewal et al , 2003; Rae et al , 2009), taxonomic descriptions, and surveys charting abundance and diversity of Phasmarhabditis in various countries (Ross et al , 2012, 2016; Wilson et al , 2012; Tandingan De Ley et al , 2014, 2016; Nermut et al , 2016a, b, 2017). There are few details and no reported methods regarding how to keep this nematode under lab conditions, like C. elegans , and whether it could be amenable to genetic manipulation.…”

Phylogenetic evidence for the invasion of a commercialized European Phasmarhabditis hermaphrodita lineage into North America and New Zealand

“…The P. hermaphrodita strain that became Nemaslug1 was isolated in Bristol, England [18]. With increased interest in this potential biocontrol there has been increased surveying efforts; P. hermaphrodita has also been discovered in Chile [27], Iran [28], Egypt [29], and more recently in New Zealand [30,31] and the west coast of North America [32,33]. It remains unclear, however, whether these reported observations of P. hermaphrodita in non-European locations constitute previously unknown natural populations of the species, or instead resulted from the introduction of Nemaslug1.…”

“…With increased interest in this potential biocontrol there has been increased surveying efforts; P . hermaphrodita has also been discovered in Chile [ 27 ], Iran [ 28 ], Egypt [ 29 ], and more recently in New Zealand [ 30 , 31 ] and the west coast of North America [ 32 , 33 ]. It remains unclear, however, whether these reported observations of P .…”