BioControl (2018) 63, 819-831

Pablo Valverde-Garcia, Cándido Santiago-Alvarez, Matthew B. Thomas, Inmaculada Garrido-Jurado and Enrique Quesada-Moraga (2018)
Comparative effects of temperature and thermoregulation on candidate strains of entomopathogenic fungi for Moroccan locust Dociostaurus maroccanus control
BioControl 63 (6), 819-831
Abstract: Strains IMI 330189 of Metarhizium acridum (Driver and Milner) J.F. Bisch., Rehner and Humber (Hypocreales: Clavicipitaceae) and EABb 90/2-Dm of Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Cordycipitaceae) are a promising biocontrol tool of Dociostaurus maroccanus (Thunberg) (Orthoptera: Acrididae), although the effects of thermoregulation and Moroccan locust-fever on the infection process of these fungi remain unknown. In vitro experiments, measuring conidial germination and hyphal growth either at constant or at fluctuating temperatures simulating thermoregulatory conditions, indicated that strain IMI 330189 had greater fitness at temperatures above 27 °C and the strain EABb 90/2-Dm was better adapted to the temperature range of 10–25 °C. These effects were mirrored in vivo, where locust thermoregulation caused a marked reduction in the virulence of EABb 90/2-Dm in comparison to no thermoregulation conditions (average survival time: 6.10 vs. 15.83 days; mortality: 100% vs. 73.7%) but only a moderate reduction in the virulence of IMI 330189 (average survival time: 4.57 vs. 8.26 days; mortality: 100% vs. 100%). Thermal gradient experiments revealed that the strain IMI 330189 induced behavioral fever in D. maroccanus (preferred temperatures approximately 4 °C above the uninfected control), although it only led to a slight reduction in virulence. Strain EABb 90/2-Dm did not induce such a clear behavioral response. Under the temperature conditions of the main breeding areas of the Moroccan locust, strain IMI 330189 is likely a better candidate for use in biocontrol, although strain EABb 90/2-Dm could be also a good alternative in more temperate environments either as a stand-alone one or in mixed combinations of the two fungal strains, potentially providing more effective control over a broader range of temperatures.
(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): Pablo Valverde Garcia, Enrique Quesada-Moraga

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

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Dociostaurus maroccanus
Beauveria bassiana (entomopathogen)	Dociostaurus maroccanus
Metarhizium acridum (entomopathogen)	Dociostaurus maroccanus