Lethal Doses of Saponins from <i>Quillaja saponaria</i> for Invasive Slug <i>Arion vulgaris</i> and Non-Target Organism <i>Enchytraeus albidus</i> (Olygochaeta: Enchytraeidae)

The slug, <i>Arion vulgaris</i> Moquin-Tandon, 1855, is a serious pest in agriculture and private gardens. White worm, <i>Enchytraeus albidus</i> Henle, 1837, is an important model of decomposer organism in the terrestrial ecosystem. Saponins, which are secondary metabolites...

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Main Authors: Mantas Adomaitis, Grita Skujienė
Format: Article
Language:English
Published: MDPI AG 2020-10-01
Series:Insects
Subjects:
Online Access:https://www.mdpi.com/2075-4450/11/11/738
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author Mantas Adomaitis
Grita Skujienė
author_facet Mantas Adomaitis
Grita Skujienė
author_sort Mantas Adomaitis
collection DOAJ
description The slug, <i>Arion vulgaris</i> Moquin-Tandon, 1855, is a serious pest in agriculture and private gardens. White worm, <i>Enchytraeus albidus</i> Henle, 1837, is an important model of decomposer organism in the terrestrial ecosystem. Saponins, which are secondary metabolites of plants, have previously been shown to have some molluscicidal effect. We investigated which doses of saponins are lethal to the slug, <i>A. vulgaris</i>, and to the non-target organism, <i>E. albidus</i>. An aqueous solution with different concentrations of saponin extract from the bark of the soap tree, <i>Quillaja saponaria</i> Mol., was used in repeat treatments. Slugs were tested in filter paper contact tests as they are naturally exposed to soil contact while crawling. Worms were tested in soil contact tests as they live below ground. It was found that lethality of saponins depends on the slug age group and the environmental temperature. The median lethal concentration (LC<sub>50</sub>, at 15 °C) on adults was 68.5 g/L, and on juveniles, 96.9 g/L. The slugs were significantly more sensitive at 2 and −1 °C compared to 15 °C. The LC<sub>50</sub> (at 6 ℃) on <i>E. albidus</i> was 2.7 g/L (or 0.5 g/kg dry weight of soil), far below those in <i>A. vulgaris</i> (at 15 ℃ and lower). The LC<sub>50</sub> for worms at -1℃ was also significantly lower than at 6 ℃. Therefore, we can conclude: (1) that <i>Q. saponaria</i> saponins may be a successful slug control tool used during colder times of the year, but its concentration should be selected according to the age group of <i>A. vulgaris</i>; (2) this measure is more toxic than expected to white worms, which limits its use.
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spelling doaj.art-d1f844933ff1422792db3dd34777110a2023-11-20T18:47:24ZengMDPI AGInsects2075-44502020-10-01111173810.3390/insects11110738Lethal Doses of Saponins from <i>Quillaja saponaria</i> for Invasive Slug <i>Arion vulgaris</i> and Non-Target Organism <i>Enchytraeus albidus</i> (Olygochaeta: Enchytraeidae)Mantas Adomaitis0Grita Skujienė1Department of Zoology, Institute of Biosciences, Life Sciences Centre, Vilnius University, Saulėtekio av. 7, LT-10257 Vilnius, LithuaniaDepartment of Zoology, Institute of Biosciences, Life Sciences Centre, Vilnius University, Saulėtekio av. 7, LT-10257 Vilnius, LithuaniaThe slug, <i>Arion vulgaris</i> Moquin-Tandon, 1855, is a serious pest in agriculture and private gardens. White worm, <i>Enchytraeus albidus</i> Henle, 1837, is an important model of decomposer organism in the terrestrial ecosystem. Saponins, which are secondary metabolites of plants, have previously been shown to have some molluscicidal effect. We investigated which doses of saponins are lethal to the slug, <i>A. vulgaris</i>, and to the non-target organism, <i>E. albidus</i>. An aqueous solution with different concentrations of saponin extract from the bark of the soap tree, <i>Quillaja saponaria</i> Mol., was used in repeat treatments. Slugs were tested in filter paper contact tests as they are naturally exposed to soil contact while crawling. Worms were tested in soil contact tests as they live below ground. It was found that lethality of saponins depends on the slug age group and the environmental temperature. The median lethal concentration (LC<sub>50</sub>, at 15 °C) on adults was 68.5 g/L, and on juveniles, 96.9 g/L. The slugs were significantly more sensitive at 2 and −1 °C compared to 15 °C. The LC<sub>50</sub> (at 6 ℃) on <i>E. albidus</i> was 2.7 g/L (or 0.5 g/kg dry weight of soil), far below those in <i>A. vulgaris</i> (at 15 ℃ and lower). The LC<sub>50</sub> for worms at -1℃ was also significantly lower than at 6 ℃. Therefore, we can conclude: (1) that <i>Q. saponaria</i> saponins may be a successful slug control tool used during colder times of the year, but its concentration should be selected according to the age group of <i>A. vulgaris</i>; (2) this measure is more toxic than expected to white worms, which limits its use.https://www.mdpi.com/2075-4450/11/11/738plant extractmolluscicideresistance<i>Arion</i><i>Enchytraeus</i>
spellingShingle Mantas Adomaitis
Grita Skujienė
Lethal Doses of Saponins from <i>Quillaja saponaria</i> for Invasive Slug <i>Arion vulgaris</i> and Non-Target Organism <i>Enchytraeus albidus</i> (Olygochaeta: Enchytraeidae)
Insects
plant extract
molluscicide
resistance
<i>Arion</i>
<i>Enchytraeus</i>
title Lethal Doses of Saponins from <i>Quillaja saponaria</i> for Invasive Slug <i>Arion vulgaris</i> and Non-Target Organism <i>Enchytraeus albidus</i> (Olygochaeta: Enchytraeidae)
title_full Lethal Doses of Saponins from <i>Quillaja saponaria</i> for Invasive Slug <i>Arion vulgaris</i> and Non-Target Organism <i>Enchytraeus albidus</i> (Olygochaeta: Enchytraeidae)
title_fullStr Lethal Doses of Saponins from <i>Quillaja saponaria</i> for Invasive Slug <i>Arion vulgaris</i> and Non-Target Organism <i>Enchytraeus albidus</i> (Olygochaeta: Enchytraeidae)
title_full_unstemmed Lethal Doses of Saponins from <i>Quillaja saponaria</i> for Invasive Slug <i>Arion vulgaris</i> and Non-Target Organism <i>Enchytraeus albidus</i> (Olygochaeta: Enchytraeidae)
title_short Lethal Doses of Saponins from <i>Quillaja saponaria</i> for Invasive Slug <i>Arion vulgaris</i> and Non-Target Organism <i>Enchytraeus albidus</i> (Olygochaeta: Enchytraeidae)
title_sort lethal doses of saponins from i quillaja saponaria i for invasive slug i arion vulgaris i and non target organism i enchytraeus albidus i olygochaeta enchytraeidae
topic plant extract
molluscicide
resistance
<i>Arion</i>
<i>Enchytraeus</i>
url https://www.mdpi.com/2075-4450/11/11/738
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AT gritaskujiene lethaldosesofsaponinsfromiquillajasaponariaiforinvasiveslugiarionvulgarisiandnontargetorganismienchytraeusalbidusiolygochaetaenchytraeidae