Applied and Environmental Microbiology (2008) 74, 802-810

M. Eugenia Nuñez-Valdez, Marco A. Calderón and Eduardo Aranda (2008)
Identification of a putative Mexican strain of Serratia entomophila pathogenic against root-damaging larvae of Scarabaeidae (Coleoptera)
Applied and Environmental Microbiology 74 (3), 802-810
Abstract: The larvae of scarab beetles, known as 'white grubs' and belonging to the genera Phyllophaga and Anomala (Coleoptera: Scarabaeidae), are regarded as soil-dwelling pests in Mexico. During a survey conducted to find pathogenic bacteria with the potential to control scarab larvae, a native Serratia sp. (strain Mor4.1) was isolated from a dead third-instar Phyllophaga blanchardi larva collected from a cornfield in Tres Marías, Morelos, Mexico. Oral bioassays using healthy P. blanchardi larvae fed with the Mor4.1 isolate showed that this strain was able to cause an antifeeding effect and a significant loss of weight. Mortality was observed for P. blanchardi, P. trichodes, and P. obsoleta in a multidose experiment. The Mor4.1 isolate also caused 100% mortality 24 h after intracoelomic inoculation of the larvae of P. blanchardi, P. ravida, Anomala donovani and the lepidopteran insect Manduca sexta. Oral and injection bioassays were performed with concentrated culture broths of the Mor4.1 isolate to search for disease symptoms and mortality caused by extracellular proteins. The results have shown that Mor4.1 broths produce significant antifeeding effects and mortality. Mor4.1 broths treated with proteinase K lost the ability to cause disease symptoms and mortality, in both the oral and the injection bioassays, suggesting the involvement of toxic proteins in the disease. The Mor4.1 isolate was identified as a putative Serratia entomophila Mor4.1 strain based on numerical taxonomy and phylogenetic analyses done with the 16S rRNA gene sequence. The potential of S. entomophila Mor4.1 and its toxins to be used in an integrated pest management program is discussed.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Maria Eugenia Nunez-Valdez

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.
	Phyllophaga obsoleta	Maize/corn (Zea mays)	Mexico
	Phyllophaga blanchardi	Maize/corn (Zea mays)	Mexico
Serratia entomophila (entomopathogen)	Phyllophaga obsoleta	Maize/corn (Zea mays)	Mexico
Serratia entomophila (entomopathogen)	Phyllophaga blanchardi	Maize/corn (Zea mays)	Mexico