PM 7/157 (1) Dendrolimus sibiricus

Abstract

Specific scope: This Standard describes a diagnostic protocol for Dendrolimus sibiricus.1 This Standard should be used in conjunction with PM 7/76 Use of EPPO diagnostic protocols.

Specific approval and amendment: Approved in 2024-03.

Authors and contributors are given in the Acknowledgements section.

Dendrolimus sibiricus Chetverikov is an insect of the order Lepidoptera, family Lasiocampidae. In its native range, D. sibiricus develops on practically all coniferous species of the Pinaceae family: Abies, Pinus, Larix, and Picea (Kirichenko & Baranchikov, 2007; Rozhkov, 1963). Major hosts are Abies nephrolepis, Abies sibirica, Larix gmelinii, Larix sibirica, and five-needle pines such as Pinus koraiensis and Pinus sibirica (EPPO, 2023a). For more information on other hosts (e.g. experimental hosts), see EPPO (2023b).

The taxonomy and nomenclature of the genus Dendrolimus are not entirely established and for some species the taxonomic position is still controversial. Most experts distinguish around 30 species in the genus, of which 16 species are found in the Palearctic region (Jeong et al., 2018; Mikkola & Ståhls, 2008; Tanaka et al., 2020). Morphologically, D. sibiricus has many similarities to the related species, D. superans, that co-occurs in the Russian Far East and China (Rozhkov, 1963). Rozhkov (1963) considered D. superans as a single species, with two subspecies: D. superans sibiricus Chetverikov and D. superans albolineatus Butler. In the current taxonomy, they are considered as separate species respectively, D. sibiricus and D. superans (EFSA, 2023). A second closely-related species is D. pini, which is native to Europe and Asia and whose distribution range partially overlaps with D. sibiricus in Central Russia (Hardin & Suazo, 2012; Kononov et al., 2016).

For an updated geographical distribution of D. sibiricus consult EPPO Global Database (EPPO, 2023a).

A datasheet providing more information on the biology is also available (EPPO, 2023b).

Name: Dendrolimus sibiricus Chetverikov, 1908.

Other scientific names: Dendrolimus laricis Chetverikov, 1903, Dendrolimus superans sibiricus Chetverikov, 1903.

Common name: Larch caterpillar, Siberian conifer silk moth, Siberian moth, Siberian silk moth.

Taxonomic position: Lepidoptera, Lasiocampidae, Dendrolimus.

EPPO Code: DENDSI.

Phytosanitary categorization: EPPO A2 list n° 308, EU Annex II A.

Larvae cause massive defoliation on coniferous hosts (Figures 1 and 2) (EPPO, 2005; Rozhkov, 1963); during outbreaks large amounts of frass are produced that make them easy to detect (Hardin & Suazo, 2012). Larvae can be found in autumn in the leaf litter under infested trees, where they overwinter. Pupae in silky cocoons are difficult to detect and pupation takes place on branches and twigs of hosts (Rozhkov, 1963). Adult males and females can be detected with light traps and adult males can also be caught in pheromone traps (Mikkola & Ståhls, 2008; Pletniev et al., 1999). Dendrolimus sibiricus and D. pini respond to the same synthetic sex pheromones, such as Z5E7-12Ald, Z5E7-12Ac, Z5E7-12OH, Z5-12Ald, E7-12Ald, E6-12Ald, E6-12OH and E7-12OH (Baranchikov et al., 2006; Klun et al., 2000; Pet'ko et al., 2004).

Due to significant polymorphism of most Dendrolimus-species, identification to species level using only external characters and appearance, cannot be done reliably. Species identification should be based on the examination of male genitalia (Baranchikov et al., 2006; EFSA, 2023; Mikkola & Ståhls, 2008; Rozhkov, 1963) or with molecular methods (DNA barcoding) (Jeong et al., 2018; Kononov et al., 2016; Mikkola & Ståhls, 2008).

Large moths can rot from the inside out (fungi) in humid conditions. This can affect molecular identification by barcoding. It is recommended to preserve material meant to be used for molecular analysis in 96% alcohol (undenatured).

Guidelines on reporting and documentation are given in EPPO Standard PM 7/77 Documentation and reporting on a diagnosis.

When performance characteristics are available, these are provided with the description of the test. Validation data are also available in the EPPO Database on Diagnostic Expertise (http://dc.eppo.int), and it is recommended to consult this database as additional information may be available there (e.g. more detailed information on analytical specificity, full validation reports, etc.).

Further information on this organism can be obtained from:

Taddei A., EURL for Insects and mites, ANSES - Laboratoire de la santé des végétaux, Unité entomologie et botanique, 755 avenue du Campus Agropolis, 34988 Montferrier-Sur-Lez Cedex, France.

Kirichenko N., Laboratory of Forest Zoology, Sukachev Institute of Forest SB RAS, Akademgorodok 50/28, Krasnoyarsk, 660036, Russia and All-Russian Plant Quarantine Center, Krasnoyarsk branch, Zhelyabova str. 6/6, Krasnoyarsk, 660020, Russia.

If you have any feedback concerning this Diagnostic Standard, or any of the tests included, or if you can provide additional validation data for tests included in this protocol that you wish to share please contact [email protected].

An annual review process is in place to identify the need for revision of diagnostic protocols. Protocols identified as needing revision are marked as such on the EPPO website.

When errata and corrigenda are in press, this will also be marked on the website.