Biocontrol Science and Technology (2005) 15, 379-392

Jarrod E. Leland, Donald E. Mullins, Larry J. Vaughan and Herman L. Warren (2005)
Effects of media composition on submerged culture spores of the entomopathogenic fungus, Metarhizium anisopliae var. acridum, Part 1: Comparison of cell wall characteristics and drying stability among three spore types
Biocontrol Science and Technology 15 (4), 379-392
Abstract: Metarhizium anisopliae var. acridum (IMI 330189) can produce at least three spore types in vitro; blastospores, submerged conidia, and aerial conidia, as defined by culturing conditions, sporogenesis, and spore morphology. This study compares morphological characteristics (dimensions and cell wall structure), chemical properties of cell wall surfaces (charge, hydrophobicity, and lectin binding), and performance (germination rate and drying stability) among these three spore types. Submerged conidia and aerial conidia both possessed thick, double-layered cell walls, with hydrophobic regions on their surfaces. However, in contrast to aerial conidia, submerged conidia have: (1) a greater affinity for the lectin concanavalin-A; (2) more anionic net surface charge; and (3) a less distinct outer rodlet layer. Blastospores were longer and more variable in length than both submerged conidia and aerial conidia, and had thinner single-layered cell walls that lacked an outer rodlet layer. Also, blastospores had a greater affinity than either conidia type for the lectin, wheat germ agglutinin. Blastaspores lacked hydrophobic regions on their surface, and had a lower anionic net surface charge than submerged conidia. In culture, blastospores germinated the fastest followed by submerged conidia, and then aerial conidia. Survival of submerged conidia and aerial conidia were similar after drying on silica gel, and was greater than that for blastospores. We provide corroborating information for differentiating spore types previously based on method of production, sporogenesis, and appearance of spores. These physical characteristics may have practical application for predicting spore-performance characteristics relevant to production and efficacy of mycoinsecticides.
(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): Larry Vaughan, Jarrod E. Leland

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
rearing/culturing/mass production
general biology - morphology - evolution

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Pest and/or beneficial records:

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