Stable isotope markers differentiate between mass-reared and wild Lepidoptera in sterile insect technique programs
Keywords:
elemental analysis-isotope ratio mass-spectrometry (EA-IRMS), sterile insects, release/recapture, isotopic signature, sugar, larval diet, markers, mothsAbstract
In this study we identified a number of moth (Lepidoptera) species that are potential targets for the sterile insect technique (SIT), and we assessed the feasibility of using stable isotope signatures as markers to distinguish mass-reared from wild moth species. Large natural differences in the isotopic signatures of commercially available sugars render them novel markers for mass-reared insects. Sugar beet (Beta vulgaris L.; Caryophyllales: Amaranthaceae), a C3 plant, has a stable isotopic signature (a measure of the ratio of the stable isotopes 13C:12C) of around −27‰ relative to Vienna Pee Dee Belemnite (VPDB; the international C isotope standard for the stable isotopes, 13C and 12C), and sugarcane (Saccharum spp.; Poales: Poaceae), a C4 plant, has an isotopic signature of around −11‰. Thus by means of such a distinct isotope ratio in the sugar in the diet, mass-reared insects can be easily distinguished from wild insects with a high degree of certainty. It was shown that the method could be extended using a multiple isotope approach, with 15N or a full suite of C, N, S and O isotopes. Intrinsic isotope marking of mass-reared moths proved to be an accurate means of distinguishing wild from mass-reared populations, based on isotopic differences between the wild host plant species and the diets used in mass-rearing, which where possible, had been manipulated to contain the isotopically divergent sugar type. This intrinsic labeling using stable isotopes could be useful in the assessment of the quality of mass-reared moths, because a stable isotope is a marker that does not affect the insect in any detrimental manner.
Resumen
En este estudio se identificaron una serie de especies de polillas (Lepidoptera) como objetivos potenciales para la técnica del insecto estéril (TIE), y se evaluó la viabilidad del uso de firmas isotópicas estables como marcadores para distinguir especies de polillas salvajes de las polillas criadas en masa. Las diferencias naturales mayores en las firmas isotópicas de los azúcares comerciales disponibles los hacen nuevos marcadores para los insectos criados en masa. La remolacha azucarera (Beta vulgaris L .; Caryophyllales: Amaranthaceae), una planta C3, tiene una firma isotópica estable (una medida de la proporción de los isótopos estables: 13C:12C) de alrededor de −27 ‰ relativa a Viena Pee Dee Belemnite (VPDB; el estandar internacional para el isótopo C de los isótopos estables, 13C y 12C), y la caña de azúcar (Saccharum spp .; Poales: Poaceae), una planta C4, que tiene una firma isotópica de alrededor de −11 ‰. Por lo tanto, por medio de esta relación de isótopos distinta en el azúcar en la dieta, los insectos criados en masa se pueden distinguir fácilmente de los insectos salvajes con un alto grado de certeza. Se demostró que el método podría ampliarse mediante un enfoque múltiple de isótopos, con 15N o un grupo completo de isótopos C, N, S y O. El marcado de los isótopos intrínsecos de las polillas criadas en masa demostró ser un medio preciso para distinguir entre las poblaciones salvajes y las poblaciones criadas en masa, basado en las diferencias isotópicas entre las especies de plantas hospederas silvestres y de las dietas usadas en la cría en masa, que cuando sea posible, habían sido manipuladas para contener el tipo de azúcar isotópicamente divergente. Este marcador intrínseco utilizando isótopos estables podría ser útil en la evaluación de la calidad de las polillas criadas en masa, porque un isótopo estable es un marcador que no afecta el insecto de cualquier manera perjudicial.
Downloads
Issue
Section
License
Copyright for any article published in Florida Entomologist is held by the author(s) of the article. Florida Entomologist is an open access journal. Florida Entomologist follows terms of the Creative Commons, Attribution Non-Commercial License (cc by-nc). By submitting and publishing articles in Florida Entomologist, authors grant the FOJ and Florida Entomologist's host institutions permission to make the article available through Internet posting and electronic dissemination, and to otherwise archive the information contained both electronically and in a hard printed version. When used, information and images obtained from articles must be referenced and cited appropriately. Articles may be reproduced for personal, educational, or archival purposes, or any non-commercial use. Permission should be sought from the author(s) for multiple, non-commercial reproduction. Written permission from the author(s) is required for any commercial reproduction.