Archives of Phytopathology and Plant Protection (2011) 44, 475-483

R.K. Gupta, Stefan T. Jaronski, K. Srivastava and K. Bali (2011)
First record on epizootics of Entomophthora grylli on grasshopper in Indian subcontinent: pathogen city and bio control potential on Oxya velox
Archives of Phytopathology and Plant Protection 44 (5), 475-483
Abstract: A naturally-occurring fungus called Entomophthora grylli was for the first time isolated from two species of grasshopper Oxya velox and Oxya vicinia in Jammu and Kashmir, India. The epizootic was confined along Indo-Pak border between 74 degrees 24' and 75 degrees 18', East longitude and 32 degrees 50' and 33 degrees 30' North latitude. The fungus proved to be highly pathogenic and the natural mortality was significantly influenced by the population density which increased from 26.00 to 73.60 over the period of epizootics. On the basis of the available literature this appears to be the first record from the Indian sub-continent. While many infected grasshoppers apparently produced neither conidia nor resting spores, the cadavers were found to be full of hyphal bodies and resting spores towards the end of epizootics. These resting spores or their germ tubes were not invasive as such but if provided a saturated environment for a week, they start germinating, resulting in germ conidia which were able to induce dermal pathogencity. Further, it was observed that the disease could not be transmitted to healthy individuals by ingestion. However, the intra-haemocoel infectivity of fresh resting spores, germinated resting spores, and germ conidia proved to be highly pathogenic as they resulted in 81.4% grasshopper mortality. Although E. grylli is fastidious, it is possible to multiply it on a large scale as protoplasts which are infective upon injection in their hosts. However, the lack of a cell wall renders them very fragile, and they are neither infective upon application to the insect's cuticle nor upon ingestion. In the present study, a method on delivery of pathogen through "sticky molasses pan trap" was developed for inducing infection in grasshoppers in a paddy nursery which would facilitate its use as a bioinsecticide, analogous to other entomopathogenic fungi.
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Link to article at publishers website
Database assignments for author(s): Rakesh K. Gupta, Stefan T. Jaronski

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
surveys/distribution/isolation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Oxya velox		India
Entomophaga grylli (entomopathogen)	Oxya velox		India