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Pathogenicity of Isolates of Serratia Marcescens towards Larvae of the Scarab Phyllophaga Blanchardi (Coleoptera).

Pineda-Castellanos ML, Rodríguez-Segura Z, Villalobos FJ, Hernández L, Lina L, Nuñez-Valdez ME - Pathogens (2015)

Bottom Line: Oral and injection bioassays using healthy Phyllophaga blanchardi larvae fed with the S. marcescens isolates showed different degrees of antifeeding effect and mortality.S. marcescens (Sm81) cell-free culture supernatant caused significant antifeeding effect and mortality to P. blanchardi larvae by oral bioassay and also mortality by injection bioassay.This insecticidal protein could have applications in agricultural biotechnology.

View Article: PubMed Central - PubMed

Affiliation: Centro de Investigación en Dinámica Celular, Instituto de Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Col. Chamilpa, CP 62209, Cuernavaca, Morelos, Mexico. mlpc@uaem.mx.

ABSTRACT
Serratia marcescens is a Gram negative bacterium (Enterobacteriaceae) often associated with infection of insects. In order to find pathogenic bacteria with the potential to control scarab larvae, several bacterial strains were isolated from the hemocoel of diseased Phyllophaga spp (Coleoptera:Scarabaeidae) larvae collected from cornfields in Mexico. Five isolates were identified as Serratia marcescens by 16S rRNA gene sequencing and biochemical tests. Oral and injection bioassays using healthy Phyllophaga blanchardi larvae fed with the S. marcescens isolates showed different degrees of antifeeding effect and mortality. No insecticidal activity was observed for Spodoptera frugiperda larvae (Lepidoptera: Noctuidae) by oral inoculation. S. marcescens (Sm81) cell-free culture supernatant caused significant antifeeding effect and mortality to P. blanchardi larvae by oral bioassay and also mortality by injection bioassay. Heat treated culture broths lost the ability to cause disease symptoms, suggesting the involvement of proteins in the toxic activity. A protein of 50.2 kDa was purified from the cell-free broth and showed insecticidal activity by injection bioassay towards P. blanchardi. Analysis of the insecticidal protein by tandem- mass spectrometry (LC-MS/MS) showed similarity to a Serralysin-like protein from S. marcescens spp. This insecticidal protein could have applications in agricultural biotechnology.

No MeSH data available.


Related in: MedlinePlus

Mortality of larvae fed with the S. marcescens isolates. Panel A. P. blanchardi. Mortality was recorded during 27 days after oral inoculation. Control groups were fed with pieces of carrot alone and also with carrot containing the non-pathogenic bacterium Serratia plymuthica ATCC15928. No significant differences are indicated by the same letter above the lines (χ2, p < 0.01); n = 10. Panel B. Spodoptera frugiperda. Mortality was recorded during 11 days. Control groups were fed with an artificial diet where bacteria were replaced with the same amount of sterile water and S. plymuthica ATCC15928. No significant differences between treatments were observed (χ2, p < 0.05).
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pathogens-04-00210-f002: Mortality of larvae fed with the S. marcescens isolates. Panel A. P. blanchardi. Mortality was recorded during 27 days after oral inoculation. Control groups were fed with pieces of carrot alone and also with carrot containing the non-pathogenic bacterium Serratia plymuthica ATCC15928. No significant differences are indicated by the same letter above the lines (χ2, p < 0.01); n = 10. Panel B. Spodoptera frugiperda. Mortality was recorded during 11 days. Control groups were fed with an artificial diet where bacteria were replaced with the same amount of sterile water and S. plymuthica ATCC15928. No significant differences between treatments were observed (χ2, p < 0.05).

Mentions: Significant mortality (p < 0.01) compared with control larvae was observed for the larvae inoculated with Sm67, Sm81, Sm73 and Sm65 after 27 days from the beginning of the test (Figure 2). The observed mortality for the control larvae was 20% and the observed mortality in the group fed with the Sm89 isolate was also 20%. On the contrary, the larvae inoculated with the other four S. marcescens isolates showed a mortality of 70% for both Sm67 and Sm81 and mortalities of 50% and 40% for Sm73 and Sm65, respectively. Larvae inoculated with the different S. marcescens isolates developed a slightly brown color compared with the beige appearance of healthy larvae observed in the control groups.


Pathogenicity of Isolates of Serratia Marcescens towards Larvae of the Scarab Phyllophaga Blanchardi (Coleoptera).

Pineda-Castellanos ML, Rodríguez-Segura Z, Villalobos FJ, Hernández L, Lina L, Nuñez-Valdez ME - Pathogens (2015)

Mortality of larvae fed with the S. marcescens isolates. Panel A. P. blanchardi. Mortality was recorded during 27 days after oral inoculation. Control groups were fed with pieces of carrot alone and also with carrot containing the non-pathogenic bacterium Serratia plymuthica ATCC15928. No significant differences are indicated by the same letter above the lines (χ2, p < 0.01); n = 10. Panel B. Spodoptera frugiperda. Mortality was recorded during 11 days. Control groups were fed with an artificial diet where bacteria were replaced with the same amount of sterile water and S. plymuthica ATCC15928. No significant differences between treatments were observed (χ2, p < 0.05).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493471&req=5

pathogens-04-00210-f002: Mortality of larvae fed with the S. marcescens isolates. Panel A. P. blanchardi. Mortality was recorded during 27 days after oral inoculation. Control groups were fed with pieces of carrot alone and also with carrot containing the non-pathogenic bacterium Serratia plymuthica ATCC15928. No significant differences are indicated by the same letter above the lines (χ2, p < 0.01); n = 10. Panel B. Spodoptera frugiperda. Mortality was recorded during 11 days. Control groups were fed with an artificial diet where bacteria were replaced with the same amount of sterile water and S. plymuthica ATCC15928. No significant differences between treatments were observed (χ2, p < 0.05).
Mentions: Significant mortality (p < 0.01) compared with control larvae was observed for the larvae inoculated with Sm67, Sm81, Sm73 and Sm65 after 27 days from the beginning of the test (Figure 2). The observed mortality for the control larvae was 20% and the observed mortality in the group fed with the Sm89 isolate was also 20%. On the contrary, the larvae inoculated with the other four S. marcescens isolates showed a mortality of 70% for both Sm67 and Sm81 and mortalities of 50% and 40% for Sm73 and Sm65, respectively. Larvae inoculated with the different S. marcescens isolates developed a slightly brown color compared with the beige appearance of healthy larvae observed in the control groups.

Bottom Line: Oral and injection bioassays using healthy Phyllophaga blanchardi larvae fed with the S. marcescens isolates showed different degrees of antifeeding effect and mortality.S. marcescens (Sm81) cell-free culture supernatant caused significant antifeeding effect and mortality to P. blanchardi larvae by oral bioassay and also mortality by injection bioassay.This insecticidal protein could have applications in agricultural biotechnology.

View Article: PubMed Central - PubMed

Affiliation: Centro de Investigación en Dinámica Celular, Instituto de Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Col. Chamilpa, CP 62209, Cuernavaca, Morelos, Mexico. mlpc@uaem.mx.

ABSTRACT
Serratia marcescens is a Gram negative bacterium (Enterobacteriaceae) often associated with infection of insects. In order to find pathogenic bacteria with the potential to control scarab larvae, several bacterial strains were isolated from the hemocoel of diseased Phyllophaga spp (Coleoptera:Scarabaeidae) larvae collected from cornfields in Mexico. Five isolates were identified as Serratia marcescens by 16S rRNA gene sequencing and biochemical tests. Oral and injection bioassays using healthy Phyllophaga blanchardi larvae fed with the S. marcescens isolates showed different degrees of antifeeding effect and mortality. No insecticidal activity was observed for Spodoptera frugiperda larvae (Lepidoptera: Noctuidae) by oral inoculation. S. marcescens (Sm81) cell-free culture supernatant caused significant antifeeding effect and mortality to P. blanchardi larvae by oral bioassay and also mortality by injection bioassay. Heat treated culture broths lost the ability to cause disease symptoms, suggesting the involvement of proteins in the toxic activity. A protein of 50.2 kDa was purified from the cell-free broth and showed insecticidal activity by injection bioassay towards P. blanchardi. Analysis of the insecticidal protein by tandem- mass spectrometry (LC-MS/MS) showed similarity to a Serralysin-like protein from S. marcescens spp. This insecticidal protein could have applications in agricultural biotechnology.

No MeSH data available.


Related in: MedlinePlus