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Title: Nitrogen fixation in the stag beetle, Ceruchus piceus (Coleoptera: Lucanidae): could insects contribute more to ecosystem nitrogen budgets than previously thought?
Abstract Nitrogen (N) is a key nutrient required by all living organisms for growth and development, but is a limiting resource for many organisms. Organisms that feed on material with low N content, such as wood, might be particularly prone to N limitation. In this study, we investigated the degree to which the xylophagous larvae of the stag beetle Ceruchus piceus (Weber) use associations with N-fixing bacteria to acquire N. We paired acetylene reduction assays by cavity ring-down absorption spectroscopy (ARACAS) with 15N2 incubations to characterize rates of N fixation within C. piceus. Not only did we detect significant N fixation activity within C. piceus larvae, but we calculated a rate that was substantially higher than most previous reports for N fixation in insects. While taking these measurements, we discovered that N fixation within C. piceus can decline rapidly in a lab setting. Consequently, our results demonstrate that previous studies, which commonly keep insects in the lab for long periods of time prior to and during measurement, may have systematically under-reported rates of N fixation in insects. This suggests that within-insect N fixation may contribute more to insect nutrition and ecosystem-scale N budgets than previously thought.  more » « less
Award ID(s):
2129542
NSF-PAR ID:
10451133
Author(s) / Creator(s):
; ; ; ;
Editor(s):
Cory, Jenny
Date Published:
Journal Name:
Environmental Entomology
Volume:
52
Issue:
4
ISSN:
0046-225X
Page Range / eLocation ID:
618 to 626
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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