Pest Management Science (2015) 71, 58-64

Guoxiong Peng and Yuxian Xia (2015)
Integration of an insecticidal scorpion toxin (BjalphaIT) gene into Metarhizium acridum enhances fungal virulence towards Locusta migratoria manilensis
Pest Management Science 71 (1), 58-64
Abstract:
BACKGROUND
Entomopathogenic fungi have been developed as biopesticides, but poor efficacy has blocked their application. One approach to improving virulence is by genetic manipulation. BjalphaIT from the venom of Buthotus judaicus is an insect-selective neurotoxin. To clarify the insecticidal potency of BjalphaIT as a virulence candidate in microbial biocontrol agents, the entomopathogenic fungus Metarhizium acridum was genetically modified with BjalphaIT, and its resulting activity against locusts (Locusta migratoria manilensis) was assessed.
RESULT
In comparison with the wild-type strain, the engineered isolate BjalphaIT-102 grew significantly quicker in locust haemolymph. Correspondingly, the median lethal dose (LC₅₀) for BjalphaIT-102 was 18.2-fold lower, and the median lethal times (LT₅₀) for BjalphaIT-102 were reduced by 28.1 and 30.4%, respectively, after topical inoculation and injection. BjalphaIT-102 formed conidia on dead locusts, although the conidial yield was reduced 1.58-fold. Moreover, there were no significant differences in germination and appressorium formation between the BjalphaIT-102 and wild-type strains.
CONCLUSION
Expression of BjalphaIT in M. acridum significantly increased virulence against locusts by shortening the in vivo infection period without affecting conidium formation on the carcasses. This study demonstrated that engineering entomopathogenic fungi to incorporate BjalphaIT offers great potential for increasing their virulence.
(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): Yuxian Xia

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
genetical engin./transgenic plants

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Locusta migratoria
Metarhizium acridum (entomopathogen)	Locusta migratoria