- Email: [email protected]
Benomyl treatment decreases fecundity of ant queens
Journal of Invertebrate Pathology 130 (2015) 61–63
Contents lists available at ScienceDirect
Journal of Invertebrate Pathology journal homepage: www.elsevier.com/locate/jip
Short Communication
Benomyl treatment decreases fecundity of ant queens Pavel Pech a, Petr Heneberg b,⇑ a b
University of Hradec Králové, Faculty of Science, Hradec Králové, Czech Republic Charles University in Prague, Third Faculty of Medicine, Prague, Czech Republic
a r t i c l e
i n f o
Article history: Received 21 February 2015 Accepted 24 June 2015 Available online 3 July 2015 Keywords: Benlate Carbendazim Environmental chemicals Methyl 1-(butylcarbamoyl)benzimidazol2-yl-carbamate Microgyne Population dynamics
a b s t r a c t Methyl benzimidazole carbamate fungicides, including benomyl, are widely used in agriculture, and to eliminate entomopathogenic infections. We treated queens of Myrmica rubra (Hymenoptera:Formicidae) infected or not by Rickia wasmannii (Laboulbeniales:Laboulbeniaceae) with benomyl, 1 mg/ml p.o. for six weeks. Benomyl did not treat the infection, and the treatment alone caused strong decrease in the fecundity of control healthy queens from 18.0 ± 8.4 to 3.7 ± 5.2 eggs per healthy queen. This is the first evidence on severe adverse effects of methyl benzimidazole carbamate fungicide on the fecundity of insects, which might be responsible for altered species composition of ant assemblages in the cultural landscape. Ó 2015 Elsevier Inc. All rights reserved.
Fungicides are frequently used in agriculture and horticulture, and many of them are also recommended to treat fungal infections in arthropods. Fungal infections by various species of the order Laboulbeniales were successfully treated in lady beetles and cockroaches by benomyl (Welch et al., 2001; Gemeno et al., 2004). Laboulbeniales are obligate parasites that grow characteristically on the cuticle of adult arthropods of ten orders, mostly of the subphylum Hexapoda. Individual laboulbenialean species display strong host specificity. Among hymenopterans, the infections were reported from ants only; three ant-specific laboulbenialean species are known from Europe. Based on the experimental evidence, Gemeno et al. (2004) recommended benomyl [methyl 1-(butylcarbamoyl)benzimidazo l-2-yl-carbamate] as an effective fungicide to treat laboulbenialean infections in hexapods at a dose 0.5–1.0 mg/ml of water or dry food, with no effects on the mortality of tested model organism, Parcoblatta lata (Brunner, 1865). Benomyl displayed promising effectivity against microsporidial infections in insects (Brooks et al., 1978), and is widely used in agriculture. Of note is that DuPont, which manufactured benomyl since year 1968, requested cancellation for benomyl registration and discontinued benomyl production in 2001. However, some other manufacturers still continue in the benomyl production and sell it for the use in agriculture in countries, where its registration has not been revoked. Its ⇑ Corresponding author at: Charles University in Prague, Third Faculty of Medicine, Ruská 87, CZ-100 00 Prague, Czech Republic. E-mail address: [email protected] (P. Heneberg). http://dx.doi.org/10.1016/j.jip.2015.06.012 0022-2011/Ó 2015 Elsevier Inc. All rights reserved.
mechanism of action involves binding to microtubules, and thus it interferes with meiosis and intracellular transport. Benomyl and other benzimidazole derivatives display acute LD50 > 2500 mg/kg in rats, detectable subchronic toxicity at 400 mg/kg in rats when administered for 90 days, acute LD50 > 100 mg/kg in fish and no detectable toxicity in bees (Matolcsy et al., 1988). In this study, we aimed to find out whether benomyl can be used to treat the infection by Rickia wasmannii in Myrmica rubra, and to elucidate whether the treatment applied is associated with any changes in the fecundity of the queens of M. rubra infected or not by R. wasmannii. For the purpose of fecundity assessment, we examined the fecundity of 46 queens of M. rubra, of which 21 (microgynes) were infected by R. wasmannii and 25 (macrogynes) were devoid of any signs of laboulbenialean infection as determined morphologically under the optical microscope. All the queens examined originated in the Czech Republic. Initially we found a nest of infected microgyne queens but despite of intense one-month long search for additional non-infected microgynes, we did not find any, and thus the control group consisted of the predominantly occurring macrogyne form of the study species. The microgyne queens examined originated from a single nest dug out in Znojmo-Popice (48.821°N, 16.015°E, 283 m a.s.l.). The macrogyne queens originated from six nests collected in Hradec Králové (50.188°N, 15.856°E, 243 m a.s.l.) and Jaromeˇrˇ (50.342°N, 15.918°E, 253 m a.s.l.). R. wasmannii is known as a widely distributed parasite of at least eight Myrmica spp. (Csata et al., 2014; Báthori et al., 2015), and was
62
P. Pech, P. Heneberg / Journal of Invertebrate Pathology 130 (2015) 61–63
recorded in the Czech Republic as well as in numerous other European countries (Báthori et al., 2015). The type specimens of R. wasmannii were collected from the study species M. rubra in Germany by Wasmann. Infection of closely related M. scabrinodis by R. wasmannii decreases the lifespan of ant workers (Csata et al., 2014; Báthori et al., 2015) and increases their sensitivity to water deprivation (Báthori et al., 2015). The ants were kept in glass petri dishes, and fed by Acheta domestica (Linnaeus, 1758) (Orthoptera: Gryllidae), honey, and were supplemented with water ad libitum. The vials with water were plugged by cotton, which was in direct contact with the water beneath. The water was supplemented or not with benomyl (1.0 mg/ml; Sigma-Aldrich, St. Louis, MO) as described (Gemeno et al., 2004). The stock benomyl solution was prepared by dissolving benomyl at 50 mg/ml in 10% ethanol, thus the final concentration of the vehicle was 0.2%. All the queens were housed under identical conditions, which consisted of the shady area with a temperature varying between 10 and 30 °C according to the ambient weather conditions. The queens were treated for six weeks (2-Jul to 12-Aug-2014), the experiment was terminated as soon as the first larvae hatched (because having the eggs-eating larvae in the experiment would compromise the resulting egg counts), and the eggs were immediately counted and the fecundity of each of the queens was evaluated. At the end of the treatment, all the queens were preserved in 96% ethanol and the numbers of thalli on the dorsal side of their heads were counted in order to evaluate the effectiveness of the benomyl treatment of infested queens. Data are shown as the mean ± SD unless stated otherwise. One-way ANOVA with Tukey’s pairwise post-tests was used to analyze the fecundity. One-tailed Fisher exact probability test was used to analyze differences in the proportion of queens laying eggs. One-tailed Student’s t-test was used to analyze the number of thalli in the untreated and treated cohorts. Linear correlation r and Spearman’s D were calculated to correlate the number of thalli with the fecundity. We observed strong, statistically significant differences in the fecundity of microgyne females of M. rubra infected or not by R. wasmannii and treated or not with benomyl (one-way ANOVA p < 0.001, df = 3, mean square 605.4, F = 17.6). All but one (90%) of the untreated infected queens laid at least several eggs, and their fecundity reached 5.0 ± 2.3 eggs per queen (median = 5 eggs, min = 0 eggs, max = 7 eggs, n = 10 queens). In the treated infected
Fig. 1. Effects of benomyl treatment on the fecundity of queens of Myrmica rubra. (A) Microgyne queens of M. rubra infected by Rickia wasmannii. (B) Macrogyne queens of M. rubra devoid of any morphologic signs of infection by R. wasmannii.
cohort, 82% of queens laid the eggs, and their fecundity decreased to only 3.7 ± 5.0 eggs per queen (median = 2 eggs, min = 0 eggs, max = 14 eggs, n = 11 queens) (Fig. 1A). The fecundity of benomyl-treated previously infected queens was similar to those of the untreated infected queens (Tukey’s pairwise post-test p > 0.05, Q = 0.73). All but one of the untreated healthy queens (92%) laid the eggs, and their mean fecundity reached 18.0 ± 8.4 eggs per queen (median = 16 eggs, min = 0 eggs, max = 30 eggs, n = 13 queens). Surprisingly, only five of the treated healthy queens (42%) laid the eggs, and their mean fecundity reached 3.7 ± 5.2 eggs per queen (median = 0 eggs, min = 0 eggs, max = 15 eggs, n = 12 queens). Thus, the treatment with benomyl alone caused a strong significant decrease in the fecundity of healthy macrogyne queens of M. rubra (Tukey’s pairwise post-test p < 0.001, Q = 8.2) (Fig. 1B). Also the differences in the proportion of queens laying eggs in the untreated and treated cohorts of healthy queens were significant (one-tailed Fisher exact probability test p = 0.01). The six weeks long treatment by benomyl at 1 mg/ml did not improve the disease. At the end of the experiments, the untreated cohort of queens displayed 30.5 ± 13.9 thalli per queen, whereas the benomyl treated queens displayed 28.5 ± 16.1 thalli per queen (the difference was not significant, one-tailed t-test p > 0.05). The fecundity did not correlate with the number of thalli found at the end of the experiment (linear correlation r = 0.20, p > 0.05; Spearman’s D = 1862.5, p > 0.05, n = 21). Combined data suggest that the p.o. administration of benomyl was ineffective when used to treat the laboulbenialean infection in ants. Moreover, we found that the treatment did not improve the fecundity of infected ant queens, and, instead, it severely decreased the fecundity of healthy control queens. Partial block of the production of eggs is consistent with the mechanism of action of benomyl and other methyl benzimidazole carbamate fungicides (MBCFs), such as carbendazim. MBCFs and their metabolites target the polymerization of tubulin, thus inhibiting the cell proliferation and division, suppressing the assembly of spindle microtubules, disturbing the chromosomal alignment at the metaphase plate, and leading to the nondisjunction, chromosome and chromatid loss (Gupta et al., 2004; Rathinasamy and Panda, 2006; Koo et al., 2009). Other effects involve also the inhibition of mitochondrial aldehyde dehydrogenase (Staub et al., 1998). The effects of benomyl and other MBCFs on the off-target organisms are poorly understood. Earthworms (Black and Neely, 1975), soil nitrification bacteria and phytopatogenic nematodes (Chen et al., 2001) are affected by benomyl treatment. Mutagenic and teratogenic effects are induced by benomyl in multiple bacterial species (Seiler, 1972), mammalian cell cultures (Styles and Garner, 1974) and rats (Lapras et al., 1973). Our data presented in this study prompt further research focusing on possible adverse effects of the MBCFs on the fitness of the off-target organisms, including the hexapods. We speculate that some widely used fungicides, such as benomyl, may severely influence the composition of ant assemblages in the cultural landscape. The queens of some species depend on continual food intake during the establishment of new colonies (semiclaustral founding), whereas the others utilize the energy stored in their fat depots (claustral founding). Some of the latter species, such as Lasius spp. and Tetramorium spp., colonize typically newly established habitats at abandoned fields. In contrast, the otherwise pioneer Myrmica spp. (with semiclaustral mode of colony founding) appear scarcely and rather later (P. Pech, unpubl.), which may be consistent with their sensitivity to the presence of residual fungicides in the soil. Concluded, we provide the first evidence on severe adverse effects of MBCF on the fecundity of insects, namely ant queens. Further research is suggested to elucidate whether such effects may be reproduced under the field conditions.
P. Pech, P. Heneberg / Journal of Invertebrate Pathology 130 (2015) 61–63
Acknowledgments The study was supported by the projects UNCE 204015 and PRVOUK P31/2012 from the Charles University in Prague.
References Báthori, F., Csata, E., Tartally, A., 2015. Rickia wasmannii increases the need for water in Myrmica scabrinodis (Ascomycota: Laboulbeniales; Hymenoptera: Formicidae). J. Invertebr. Pathol. 126, 78–82. Black, W.M., Neely, D., 1975. Effect of soil-injected benomyl on resident earthworm populations. Pestic. Sci. 6, 543–545. Brooks, W.M., Cranford, J.D., Pearce, L.W., 1978. Benomyl: effectiveness against the microsporidian Nosema heliothidis in the corn earworm, Heliothis zea. J. Invertebr. Pathol. 31, 239–245. Chen, S.K., Edwards, C.A., Subler, S., 2001. Effects of the fungicides benomyl, captan and chlorothalonil on soil microbial activity and nitrogen dynamics in laboratory incubations. Soil Biol. Biochem. 33, 1971–1980. Csata, E., Erös, K., Markó, B., 2014. Effects of the ectoparasitic fungus Rickia wasmannii on its ant host Myrmica scabrinodis: changes in host mortality and behavior. Insect. Soc. 61, 247–252. Gemeno, C., Zurek, L., Schal, C., 2004. Control of Herpomyces spp. (Ascomycetes: Laboulbeniales) infection in the wood cockroach, Parcoblatta lata (Dictyoptera: Blattodea: Blattellidae), with benomyl. J. Invertebr. Pathol. 85, 132–135.
63
Gupta, K., Bishop, J., Peck, A., Brown, J., Wilson, L., Panda, D., 2004. Antimitotic antifungal compound benomyl inhibits brain microtubule polymerization and dynamics and cancer cell proliferation at mitosis, by binding to a novel site in tubulin. Biochemistry 43, 6645–6655. Koo, B.S., Park, H., Kalme, S., Park, H.-Y., Han, J.W., Yeo, Y.-S., Yoon, S.-H., Kim, S.-J., Lee, C.-M., Yoon, M.-Y., 2009. a- and b-tubulin from Phytophthora capsici KACC 40483: molecular cloning, biochemical characterization, and antimicrotubule screening. Appl. Microbiol. Biotechnol. 82, 513–524. Lapras, M., Delatour, P., Deschanel, J., Lourge, G., Camps, D., Regnier, B., 1973. Étude expérimentale de ˇl activité tératogéne du parbendazole chez le rat. Bull. Soc. sci. vét. Lyon 75, 117–130. Matolcsy, G., Nádasy, M., Andriska, V., 1988. Pesticide chemistry. Stud. Environ. Sci. 32, 3–808. Rathinasamy, K., Panda, D., 2006. Suppression of microtubule dynamics by benomyl decreases tension across kinetochore pairs and induces apoptosis in cancer cells. FEBS J. 273, 4114–4128. Seiler, J.P., 1972. The mutagenicity of benzimidazole and benzimidazole derivatives. I. Forward and reverse mutations in Salmonella typhimurium caused by benzimidazole and some of its derivatives. Mutat. Res. 15, 273–276. Staub, R.E., Quistad, G.B., Casida, J.E., 1998. Mechanism for benomyl action as a mitochondrial aldehyde dehydrogenase inhibitor in mice. Chem. Res. Toxicol. 11, 535–543. Styles, J.A., Garner, R., 1974. Benzimidazolecarbamate methyl ester-evaluation of its effects in vivo and in vitro. Mutat. Res. 26, 177–187. Welch, V.L., Sloggett, J.J., Webberley, K.M., Hurst, G.D.D., 2001. Short-range clinal variation in the prevalence of a sexually transmitted fungus associated with urbanization. Ecol. Entomol. 26, 547–550.
Contents lists available at ScienceDirect
Journal of Invertebrate Pathology journal homepage: www.elsevier.com/locate/jip
Short Communication
Benomyl treatment decreases fecundity of ant queens Pavel Pech a, Petr Heneberg b,⇑ a b
University of Hradec Králové, Faculty of Science, Hradec Králové, Czech Republic Charles University in Prague, Third Faculty of Medicine, Prague, Czech Republic
a r t i c l e
i n f o
Article history: Received 21 February 2015 Accepted 24 June 2015 Available online 3 July 2015 Keywords: Benlate Carbendazim Environmental chemicals Methyl 1-(butylcarbamoyl)benzimidazol2-yl-carbamate Microgyne Population dynamics
a b s t r a c t Methyl benzimidazole carbamate fungicides, including benomyl, are widely used in agriculture, and to eliminate entomopathogenic infections. We treated queens of Myrmica rubra (Hymenoptera:Formicidae) infected or not by Rickia wasmannii (Laboulbeniales:Laboulbeniaceae) with benomyl, 1 mg/ml p.o. for six weeks. Benomyl did not treat the infection, and the treatment alone caused strong decrease in the fecundity of control healthy queens from 18.0 ± 8.4 to 3.7 ± 5.2 eggs per healthy queen. This is the first evidence on severe adverse effects of methyl benzimidazole carbamate fungicide on the fecundity of insects, which might be responsible for altered species composition of ant assemblages in the cultural landscape. Ó 2015 Elsevier Inc. All rights reserved.
Fungicides are frequently used in agriculture and horticulture, and many of them are also recommended to treat fungal infections in arthropods. Fungal infections by various species of the order Laboulbeniales were successfully treated in lady beetles and cockroaches by benomyl (Welch et al., 2001; Gemeno et al., 2004). Laboulbeniales are obligate parasites that grow characteristically on the cuticle of adult arthropods of ten orders, mostly of the subphylum Hexapoda. Individual laboulbenialean species display strong host specificity. Among hymenopterans, the infections were reported from ants only; three ant-specific laboulbenialean species are known from Europe. Based on the experimental evidence, Gemeno et al. (2004) recommended benomyl [methyl 1-(butylcarbamoyl)benzimidazo l-2-yl-carbamate] as an effective fungicide to treat laboulbenialean infections in hexapods at a dose 0.5–1.0 mg/ml of water or dry food, with no effects on the mortality of tested model organism, Parcoblatta lata (Brunner, 1865). Benomyl displayed promising effectivity against microsporidial infections in insects (Brooks et al., 1978), and is widely used in agriculture. Of note is that DuPont, which manufactured benomyl since year 1968, requested cancellation for benomyl registration and discontinued benomyl production in 2001. However, some other manufacturers still continue in the benomyl production and sell it for the use in agriculture in countries, where its registration has not been revoked. Its ⇑ Corresponding author at: Charles University in Prague, Third Faculty of Medicine, Ruská 87, CZ-100 00 Prague, Czech Republic. E-mail address: [email protected] (P. Heneberg). http://dx.doi.org/10.1016/j.jip.2015.06.012 0022-2011/Ó 2015 Elsevier Inc. All rights reserved.
mechanism of action involves binding to microtubules, and thus it interferes with meiosis and intracellular transport. Benomyl and other benzimidazole derivatives display acute LD50 > 2500 mg/kg in rats, detectable subchronic toxicity at 400 mg/kg in rats when administered for 90 days, acute LD50 > 100 mg/kg in fish and no detectable toxicity in bees (Matolcsy et al., 1988). In this study, we aimed to find out whether benomyl can be used to treat the infection by Rickia wasmannii in Myrmica rubra, and to elucidate whether the treatment applied is associated with any changes in the fecundity of the queens of M. rubra infected or not by R. wasmannii. For the purpose of fecundity assessment, we examined the fecundity of 46 queens of M. rubra, of which 21 (microgynes) were infected by R. wasmannii and 25 (macrogynes) were devoid of any signs of laboulbenialean infection as determined morphologically under the optical microscope. All the queens examined originated in the Czech Republic. Initially we found a nest of infected microgyne queens but despite of intense one-month long search for additional non-infected microgynes, we did not find any, and thus the control group consisted of the predominantly occurring macrogyne form of the study species. The microgyne queens examined originated from a single nest dug out in Znojmo-Popice (48.821°N, 16.015°E, 283 m a.s.l.). The macrogyne queens originated from six nests collected in Hradec Králové (50.188°N, 15.856°E, 243 m a.s.l.) and Jaromeˇrˇ (50.342°N, 15.918°E, 253 m a.s.l.). R. wasmannii is known as a widely distributed parasite of at least eight Myrmica spp. (Csata et al., 2014; Báthori et al., 2015), and was
62
P. Pech, P. Heneberg / Journal of Invertebrate Pathology 130 (2015) 61–63
recorded in the Czech Republic as well as in numerous other European countries (Báthori et al., 2015). The type specimens of R. wasmannii were collected from the study species M. rubra in Germany by Wasmann. Infection of closely related M. scabrinodis by R. wasmannii decreases the lifespan of ant workers (Csata et al., 2014; Báthori et al., 2015) and increases their sensitivity to water deprivation (Báthori et al., 2015). The ants were kept in glass petri dishes, and fed by Acheta domestica (Linnaeus, 1758) (Orthoptera: Gryllidae), honey, and were supplemented with water ad libitum. The vials with water were plugged by cotton, which was in direct contact with the water beneath. The water was supplemented or not with benomyl (1.0 mg/ml; Sigma-Aldrich, St. Louis, MO) as described (Gemeno et al., 2004). The stock benomyl solution was prepared by dissolving benomyl at 50 mg/ml in 10% ethanol, thus the final concentration of the vehicle was 0.2%. All the queens were housed under identical conditions, which consisted of the shady area with a temperature varying between 10 and 30 °C according to the ambient weather conditions. The queens were treated for six weeks (2-Jul to 12-Aug-2014), the experiment was terminated as soon as the first larvae hatched (because having the eggs-eating larvae in the experiment would compromise the resulting egg counts), and the eggs were immediately counted and the fecundity of each of the queens was evaluated. At the end of the treatment, all the queens were preserved in 96% ethanol and the numbers of thalli on the dorsal side of their heads were counted in order to evaluate the effectiveness of the benomyl treatment of infested queens. Data are shown as the mean ± SD unless stated otherwise. One-way ANOVA with Tukey’s pairwise post-tests was used to analyze the fecundity. One-tailed Fisher exact probability test was used to analyze differences in the proportion of queens laying eggs. One-tailed Student’s t-test was used to analyze the number of thalli in the untreated and treated cohorts. Linear correlation r and Spearman’s D were calculated to correlate the number of thalli with the fecundity. We observed strong, statistically significant differences in the fecundity of microgyne females of M. rubra infected or not by R. wasmannii and treated or not with benomyl (one-way ANOVA p < 0.001, df = 3, mean square 605.4, F = 17.6). All but one (90%) of the untreated infected queens laid at least several eggs, and their fecundity reached 5.0 ± 2.3 eggs per queen (median = 5 eggs, min = 0 eggs, max = 7 eggs, n = 10 queens). In the treated infected
Fig. 1. Effects of benomyl treatment on the fecundity of queens of Myrmica rubra. (A) Microgyne queens of M. rubra infected by Rickia wasmannii. (B) Macrogyne queens of M. rubra devoid of any morphologic signs of infection by R. wasmannii.
cohort, 82% of queens laid the eggs, and their fecundity decreased to only 3.7 ± 5.0 eggs per queen (median = 2 eggs, min = 0 eggs, max = 14 eggs, n = 11 queens) (Fig. 1A). The fecundity of benomyl-treated previously infected queens was similar to those of the untreated infected queens (Tukey’s pairwise post-test p > 0.05, Q = 0.73). All but one of the untreated healthy queens (92%) laid the eggs, and their mean fecundity reached 18.0 ± 8.4 eggs per queen (median = 16 eggs, min = 0 eggs, max = 30 eggs, n = 13 queens). Surprisingly, only five of the treated healthy queens (42%) laid the eggs, and their mean fecundity reached 3.7 ± 5.2 eggs per queen (median = 0 eggs, min = 0 eggs, max = 15 eggs, n = 12 queens). Thus, the treatment with benomyl alone caused a strong significant decrease in the fecundity of healthy macrogyne queens of M. rubra (Tukey’s pairwise post-test p < 0.001, Q = 8.2) (Fig. 1B). Also the differences in the proportion of queens laying eggs in the untreated and treated cohorts of healthy queens were significant (one-tailed Fisher exact probability test p = 0.01). The six weeks long treatment by benomyl at 1 mg/ml did not improve the disease. At the end of the experiments, the untreated cohort of queens displayed 30.5 ± 13.9 thalli per queen, whereas the benomyl treated queens displayed 28.5 ± 16.1 thalli per queen (the difference was not significant, one-tailed t-test p > 0.05). The fecundity did not correlate with the number of thalli found at the end of the experiment (linear correlation r = 0.20, p > 0.05; Spearman’s D = 1862.5, p > 0.05, n = 21). Combined data suggest that the p.o. administration of benomyl was ineffective when used to treat the laboulbenialean infection in ants. Moreover, we found that the treatment did not improve the fecundity of infected ant queens, and, instead, it severely decreased the fecundity of healthy control queens. Partial block of the production of eggs is consistent with the mechanism of action of benomyl and other methyl benzimidazole carbamate fungicides (MBCFs), such as carbendazim. MBCFs and their metabolites target the polymerization of tubulin, thus inhibiting the cell proliferation and division, suppressing the assembly of spindle microtubules, disturbing the chromosomal alignment at the metaphase plate, and leading to the nondisjunction, chromosome and chromatid loss (Gupta et al., 2004; Rathinasamy and Panda, 2006; Koo et al., 2009). Other effects involve also the inhibition of mitochondrial aldehyde dehydrogenase (Staub et al., 1998). The effects of benomyl and other MBCFs on the off-target organisms are poorly understood. Earthworms (Black and Neely, 1975), soil nitrification bacteria and phytopatogenic nematodes (Chen et al., 2001) are affected by benomyl treatment. Mutagenic and teratogenic effects are induced by benomyl in multiple bacterial species (Seiler, 1972), mammalian cell cultures (Styles and Garner, 1974) and rats (Lapras et al., 1973). Our data presented in this study prompt further research focusing on possible adverse effects of the MBCFs on the fitness of the off-target organisms, including the hexapods. We speculate that some widely used fungicides, such as benomyl, may severely influence the composition of ant assemblages in the cultural landscape. The queens of some species depend on continual food intake during the establishment of new colonies (semiclaustral founding), whereas the others utilize the energy stored in their fat depots (claustral founding). Some of the latter species, such as Lasius spp. and Tetramorium spp., colonize typically newly established habitats at abandoned fields. In contrast, the otherwise pioneer Myrmica spp. (with semiclaustral mode of colony founding) appear scarcely and rather later (P. Pech, unpubl.), which may be consistent with their sensitivity to the presence of residual fungicides in the soil. Concluded, we provide the first evidence on severe adverse effects of MBCF on the fecundity of insects, namely ant queens. Further research is suggested to elucidate whether such effects may be reproduced under the field conditions.
P. Pech, P. Heneberg / Journal of Invertebrate Pathology 130 (2015) 61–63
Acknowledgments The study was supported by the projects UNCE 204015 and PRVOUK P31/2012 from the Charles University in Prague.
References Báthori, F., Csata, E., Tartally, A., 2015. Rickia wasmannii increases the need for water in Myrmica scabrinodis (Ascomycota: Laboulbeniales; Hymenoptera: Formicidae). J. Invertebr. Pathol. 126, 78–82. Black, W.M., Neely, D., 1975. Effect of soil-injected benomyl on resident earthworm populations. Pestic. Sci. 6, 543–545. Brooks, W.M., Cranford, J.D., Pearce, L.W., 1978. Benomyl: effectiveness against the microsporidian Nosema heliothidis in the corn earworm, Heliothis zea. J. Invertebr. Pathol. 31, 239–245. Chen, S.K., Edwards, C.A., Subler, S., 2001. Effects of the fungicides benomyl, captan and chlorothalonil on soil microbial activity and nitrogen dynamics in laboratory incubations. Soil Biol. Biochem. 33, 1971–1980. Csata, E., Erös, K., Markó, B., 2014. Effects of the ectoparasitic fungus Rickia wasmannii on its ant host Myrmica scabrinodis: changes in host mortality and behavior. Insect. Soc. 61, 247–252. Gemeno, C., Zurek, L., Schal, C., 2004. Control of Herpomyces spp. (Ascomycetes: Laboulbeniales) infection in the wood cockroach, Parcoblatta lata (Dictyoptera: Blattodea: Blattellidae), with benomyl. J. Invertebr. Pathol. 85, 132–135.
63
Gupta, K., Bishop, J., Peck, A., Brown, J., Wilson, L., Panda, D., 2004. Antimitotic antifungal compound benomyl inhibits brain microtubule polymerization and dynamics and cancer cell proliferation at mitosis, by binding to a novel site in tubulin. Biochemistry 43, 6645–6655. Koo, B.S., Park, H., Kalme, S., Park, H.-Y., Han, J.W., Yeo, Y.-S., Yoon, S.-H., Kim, S.-J., Lee, C.-M., Yoon, M.-Y., 2009. a- and b-tubulin from Phytophthora capsici KACC 40483: molecular cloning, biochemical characterization, and antimicrotubule screening. Appl. Microbiol. Biotechnol. 82, 513–524. Lapras, M., Delatour, P., Deschanel, J., Lourge, G., Camps, D., Regnier, B., 1973. Étude expérimentale de ˇl activité tératogéne du parbendazole chez le rat. Bull. Soc. sci. vét. Lyon 75, 117–130. Matolcsy, G., Nádasy, M., Andriska, V., 1988. Pesticide chemistry. Stud. Environ. Sci. 32, 3–808. Rathinasamy, K., Panda, D., 2006. Suppression of microtubule dynamics by benomyl decreases tension across kinetochore pairs and induces apoptosis in cancer cells. FEBS J. 273, 4114–4128. Seiler, J.P., 1972. The mutagenicity of benzimidazole and benzimidazole derivatives. I. Forward and reverse mutations in Salmonella typhimurium caused by benzimidazole and some of its derivatives. Mutat. Res. 15, 273–276. Staub, R.E., Quistad, G.B., Casida, J.E., 1998. Mechanism for benomyl action as a mitochondrial aldehyde dehydrogenase inhibitor in mice. Chem. Res. Toxicol. 11, 535–543. Styles, J.A., Garner, R., 1974. Benzimidazolecarbamate methyl ester-evaluation of its effects in vivo and in vitro. Mutat. Res. 26, 177–187. Welch, V.L., Sloggett, J.J., Webberley, K.M., Hurst, G.D.D., 2001. Short-range clinal variation in the prevalence of a sexually transmitted fungus associated with urbanization. Ecol. Entomol. 26, 547–550.