Bacillus thuringiensis Bioinsecticides Induce Developmental Defects in Non-Target Drosophila melanogaster Larvae
- Others:
- Institut Sophia Agrobiotech (ISA) ; Université Nice Sophia Antipolis (1965 - 2019) (UNS) ; COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement (INRAE)-Université Côte d'Azur (UCA)
- Institut Olga Triballat (PR2016-19)
- ANSES PNR-EST & ECOPHYTO II (EST-2017-22)/Agence Nationale de Sécurité Sanitaire de l'Alimentation, de l'Environnement et du Travail
- ANR-11-LABX-0028,SIGNALIFE,Réseau d'Innovation sur les Voies de Signalisation en Sciences de la Vie(2011)
- ANR-13-CESA-0003,ImBio,Impacts d'une intoxication chronique par des bioinsecticides Bt k sur l'homéostasie intestinale et la réponse immunitaire: des insectes aux mammifères(2013)
Description
Bioinsecticides made from the bacterium Bacillus thuringiensis (Bt) are the bestselling bioinsecticide worldwide. Among Bt bioinsecticides, those based on the strain Bt subsp. kurstaki (Btk) are widely used in farming to specifically control pest lepidopteran larvae. Although there is much evidence of the lack of acute lethality of Btk products for non-target animals, only scarce data are available on their potential non-lethal developmental adverse effects. Using a concentration that could be reached in the field upon sprayings, we show that Btk products impair growth and developmental time of the non-target dipteran Drosophila melanogaster. We demonstrate that these effects are mediated by the synergy between Btk bacteria and Btk insecticidal toxins. We further show that Btk bioinsecticides trigger intestinal cell death and alter protein digestion without modifying the food intake and feeding behavior of the larvae. Interestingly, these harmful effects can be mitigated by a protein-rich diet or by adding the probiotic bacterium Lactobacillus plantarum into the food. Finally, we unravel two new cellular mechanisms allowing the larval midgut to maintain its integrity upon Btk aggression: First the flattening of surviving enterocytes and second, the generation of new immature cells arising from the adult midgut precursor cells. Together, these mechanisms participate to quickly fill in the holes left by the dying enterocytes
Abstract
International audience
Additional details
- URL
- https://hal.archives-ouvertes.fr/hal-02987070
- URN
- urn:oai:HAL:hal-02987070v1
- Origin repository
- UNICA