Vairimorpha necatrix in Adipose Cells of Trichoplusia ni

Abstract

Vairimorpha necatrix infected adipose ceiis of the fat body organ of Trichoplusia ni larvae 3–31/2 days after exposure of the larvae to infective spores. During the subsequent 4–6 days, the parasitized adipose cells were hypertrophied in part due to the rapid propagation of V. necatrix schizonts. A calcium‐sensitive tubule network developed at the interface of the schizonts and the adipose ceil cytoplasm. The paired nuclei of V. necatrix have pores at the nuclear interface. The pores for each nucleus at this interface are spatially positioned so that they are in conjunction; hence, there is the potential for a channel system between the 2 nuclei.

The pathogenicity of Vairimorpha necatrix (Microspora: Microsporidia) against the tomato moth, Lacanobia oleracea (Lepidoptera: Noctuidae) and its potential use for the control of lepidopteran glasshouse pests

“…During this study, infected L oleracea larvae often died shortly after ecdysis after failing to completely slough off the old exoskeleton. Death during or shortly after moulting has been observed in other noctuid species,16, 17 and is caused by the partially sloughed cuticle constricting the swollen fat body (the main site of infection for V necatrix )1, 18–20 resulting in bacterial septicaemia 17…”

Establishment of the new genus Paranosema based on the ultrastructure and molecular phylogeny of the type species Paranosema grylli Gen. Nov., Comb. Nov. (Sokolova, Selezniov, Dolgikh, Issi 1994), from the cricket Gryllus bimaculatus Deg

“…2I). The characteristic ''tubular structure'' described for various microsporidia infecting insect fat body (Darwish et al, 1989;Wang et al, 1991) appeared in the host cell cytoplasm when the parasite entered the second merogonial stage (Fig. 4C).…”

Nosema ceranae in European honey bees (Apis mellifera)

“…The infectivity of N. ceranae to A. mellifera is not surprising since many microsporidia exploit multiple hosts. As an example, the species Nosema necatrix (described by Kramer (1965)) and later redescribed as Vairimorpha necatrix (Pilley, 1976), which is phylogenetically closer to N. ceranae than to N. apis (Fries et al, 1996;Chen et al, 2009), successfully completes development in a variety of lepidopteran hosts (Darwish et al, 1989;Kramer, 1965;Nordin and Maddox, 1974;Pilley, 1976). Microsporidia infections in A. cerana had been described prior to the description of N. ceranae and were assumed to be infections by N. apis (Lian, 1980;Singh, 1975;Yakobson et al, 1992).…”