Nematology (2014) 16, 929-936

Temesgen Addis, Asmamaw Teshome, Olaf Strauch and Ralf-Udo Ehlers (2014)
Life history trait analysis of the entomopathogenic nematode Steinernema riobrave
Nematology 16 (8), 929-936
Abstract: Life history traits (LHT) of Steinernema riobrave strain Sr 7-12 and Sr HYB19 were assessed at 25°C in monoxenic culture using a hanging drop technique. The LHT were studied with 5 × 10⁹, 10 × 10⁹ and 20 × 10⁹ cells ml^-1 of Xenorhabdus cabanillasii in semi-solid Nematode Growth Gelrite. Increased X. cabanillasii densities had a significant positive influence on offspring production on both Sr 7-12 and the hybrid Sr HYB19. At the higher bacterial food density, the total fertility rate (TFR) per female of Sr 7-12 was 2022 offspring and the net reproductive rate (R0) reached 1904 offspring. Similarly, for Sr HYB19, the TFR per female was 2434 and R₀ was 1903. The percentage offspring produced via intra-uterine development (endotokia matricida) was relatively higher at 5 × 10⁹ bacterial cells ml^-1 than at higher bacterial density, with 64% and 66% of the total offspring produced by Sr 7-12 and Sr HYB19, respectively. A positive correlation (R=0.648) was recorded for offspring production and bacterial food density and for female body volume with bacterial density (R=0.610). Female nematodes survived longer at higher bacterial food density; however, females of both strains could not survive longer than 7.8 days, beginning from hatching and always ending 1 day after initiation of endotokia matricida. Based on LHT results, there is a potential to maximise yield of dauer juveniles in liquid culture through increasing bacterial food density.
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Link to article at publishers website
Database assignments for author(s): Ralf-Udo Ehlers

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Steinernema riobrave/Xenorhabdus cabanillasii (entomopathogen)