Isolation, characterization and virulence of bacteria from Ostrinia nubilalis (Lepidoptera: Pyralidae)

Abstract

<jats:title>Abstract</jats:title><jats:p>Isolation, characterization and virulence of the culturable bacteria from entire tissues of larval Ostrinia nubilalis (Hübner) (Lepidoptera: Pyralidae) were studied to obtain new microbes for biological control. A total of 16 bacteria were isolated from living and dead larvae collected from different maize fields in the Eastern Black Sea Region of Turkey. The bacterial microbiota of O. nubilalis were identified as Pseudomonas aeruginosa (On1), Brevundimonas aurantiaca (On2), Chryseobacterium formosense (On3), Acinetobacter sp. (On4), Microbacterium thalassium (On5), Bacillus megaterium (On6), Serratia sp. (On7), Ochrobactrum sp. (On8), Variovorax paradoxus (On9), Corynebacterium glutamicum (On10), Paenibacillus sp. (On11), Alcaligenes faecalis (On12), Microbacterium testaceum (On13), Leucobacter sp. (On14), Leucobacter sp. (On15) and Serratia marcescens (On16) based on their morphological and biochemical characteristics. A partial sequence of the 16S rRNA gene was also determined to confirm strain identification. The highest insecticidal activities were obtained from P. aeruginosa On1 (80%), Serratia sp. On7 (60%), V. paradoxus On9 (50%) and S. marcescens On16 (50%) against larvae 14 days after treatment (p &lt; 0.05). Also, the highest activity from previously isolated Bacillus species was observed from Bacillus thuringiensis subsp. tenebrionis Xd3 with 80% mortality within the same period (p &lt; 0.05). Our results indicate that P. aeruginosa On1, Serratia sp. On7, V. paradoxus On9, S. marcescens On16 and B. thuringiensis subsp. tenebrionis Xd3 show potential for biocontrol of O. nubilalis.</jats:p>

Characterization and pathogenicity assessment of gut-associated microbes of muga silkworm Antheraea assamensis Helfer (Lepidoptera: Saturniidae)

“…Among all the isolated strains, S. marcescensis was found to be most pathogenic one and showed ~73% mortality of the host (Gokce et al, 2010). Recently, it is reported that the gut of Ostrinia nubilalis harbors P. aeruginosa, Serratia sp., Variovorax paradoxus and S. marcescens bacterial strains which is found to be pathogenic against the host (Secil et al, 2012). These results confirm the presence of pathogenic stains in gut of different organisms and signify its vital role in disease development.…”

Pathogenicity of bacteria isolated from gut of Spodoptera litura (Lepidoptera: Noctuidae) and fitness costs of insect associated with consumption of bacteria

“…Out of which S. marcescens showed highest mortality (73%) against larvae within 10 days (Gokce et al, 2010). Similarly P. aeruginosa, Serratia sp., Variovorax paradoxus and S. marcescens associated with the gut of Ostrinia nubilalis (Hubner) have been reported to be pathogenic against their host (Secil et al, 2012). Çakici et al (2014) also documented the pathogenicity of internal bacteria of S. littoralis viz.…”

The internal bacterial diversity of stored product pests

“…The most common species of this genus is A. faecalis which is commonly found in the intestinal canal of vertebrates, decaying materials, dairy products, water and soil (Busse and Stolz 2006). Alcaligenes faecalis has also been isolated from many insect species such as Ips sexdentatus (Boern) (Coleoptera: Curculionidae), Ostrinia nubilalis (Hübner) (Lepidoptera: Pyralidae) and Tapinoma melanocephalum (Fabricius) (Hymenoptera: Formicidae) (Sevim et al 2012a: Secil et al 2012: Pesquero et al 2012. We also isolated one strain of A. faecalis from P. operculella, showing a first isolation of this species from any stored product pest.…”