title: Germination polarity of Beauveria bassiana conidia and its possible correlation with virulence.
abstract: Three different germination types of conidia; unidirectional, bidirectional and multidirectional, were revealed through microscopic observations for eight Beauveria bassiana isolates germinated on Sabouraud dextrose agar. Canonical correlation analysis indicated that there is a positive correlation between unidirectional germination and virulence against diamondback moth, Plutella xylostella and the Colorado potato beetle, Leptinotarsa decemlineata. Scanning electron microscopy revealed different in vivo behaviors for unipolar- and bipolar-germinated conidia. Unipolar-germinated conidia produced a strong germ tube with mostly appressorium-like structures while bipolar-germinated conidia continued to invasive hyphal growth without any penetration, indicating that germination polarity in one way or another may be an indicator of pathogenic ability.
authors.affiliation: Department of Plant Protection, College of Agriculture, University of Tehran, Karaj, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Talaei-Hassanloui
authors.forename: Aziz
authors.initials: A
authors.lastname: Kharazi-pakdel
authors.forename: Mark S
authors.initials: MS
authors.lastname: Goettel
authors.forename: Shannan
authors.initials: S
authors.lastname: Little
authors.forename: Javad
authors.initials: J
authors.lastname: Mozaffari
mesh_terms: D000818:Animals; D052982:Beauveria / Q000254:growth & development* / Q000472:pathogenicity* / Q000648:ultrastructure; D001517:Coleoptera / Q000382:microbiology*; D006790:Host-Parasite Interactions; D008855:Microscopy, Electron, Scanning; D009036:Moths / Q000382:microbiology*; D010572:Pest Control, Biological / Q000379:methods; D013172:Spores, Fungal / Q000254:growth & development* / Q000472:pathogenicity* / Q000648:ultrastructure; D014774:Virulence