title: Pathogenicity of a microsporidium isolate from the diamondback moth against Noctuid moths: characterization and implications for microbiological pest management.
abstract: BACKGROUND
  Due to problems with chemical control, there is increasing interest in the use of microsporidia for control of lepidopteran pests. However, there have been few studies to evaluate the susceptibility of exotic species to microsporidia from indigenous Lepidoptera.
  
  
  RESULTS
  We investigated some biological characteristics of the microsporidian parasite isolated from wild Plutella xylostella (PX) and evaluated its pathogenicity on the laboratory responses of sympatric invasive and resident noctuid moths. There were significant differences in spore size and morphology between PX and Spodoptera litura (SL) isolates. Spores of PX isolate were ovocylindrical, while those of SL were oval. PX spores were 1.05 times longer than those of SL, which in turn were 1.49 times wider than those of the PX. The timing of infection peaks was much shorter in SL and resulted in earlier larval death. There were no noticeable differences in amplicon size (two DNA fragments were each about 1200 base pairs in length). Phylogenetic analysis revealed that the small subunit (SSU) rRNA gene sequences of the two isolates shared a clade with Nosema/Vairimorpha sequences. The absence of octospores in infected spodopteran tissues suggested that PX and SL spores are closely related to Nosema plutellae and N. bombycis, respectively. Both SL and S. exigua (SE) exhibited susceptibility to the PX isolate infection, but showed different infection patterns. Tissular infection was more diverse in the former and resulted in much greater spore production and larval mortality. Microsporidium-infected larvae pupated among both infected and control larvae, but adult emergence occurred only in the second group.
  
  
  CONCLUSIONS
  The PX isolate infection prevented completion of development of most leafworm and beet armyworm larvae. The ability of the microsporidian isolate to severely infect and kill larvae of both native and introduced spodopterans makes it a valuable candidate for biocontrol against lepidopteran pests.
authors.affiliation: Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia.
authors.forename: Idris Abd
authors.initials: IA
authors.lastname: Ghani
authors.affiliation: School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia.
authors.forename: Hamady
authors.initials: H
authors.lastname: Dieng
authors.affiliation: Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia.
authors.forename: Zainal Abidin
authors.initials: ZA
authors.lastname: Abu Hassan
authors.affiliation: Department of Biomedical Science, Islamic University of Malaysia, Pahang, Malaysia.
authors.forename: Norazsida
authors.initials: N
authors.lastname: Ramli
authors.affiliation: Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia.
authors.forename: Nadia
authors.initials: N
authors.lastname: Kermani
authors.affiliation: Faculty of Pharmaceutical Sciences, Fukuoka University, Japan.
authors.forename: Tomomitsu
authors.initials: T
authors.lastname: Satho
authors.affiliation: School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia.
authors.forename: Hamdan
authors.initials: H
authors.lastname: Ahmad
authors.affiliation: Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, Kuching, Malaysia.
authors.forename: Fatimah Bt
authors.initials: FB
authors.lastname: Abang
authors.affiliation: Faculty of Pharmaceutical Sciences, Fukuoka University, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Fukumitsu
authors.affiliation: School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia.
authors.forename: Abu Hassan
authors.initials: AH
authors.lastname: Ahmad
mesh_terms: D000818:Animals; D061046:Biological Control Agents; D004271:DNA, Fungal / Q000145:classification* / Q000235:genetics; D058507:Host Specificity; D007413:Intestinal Mucosa / Q000382:microbiology; D007814:Larva / Q000382:microbiology*; D021861:Microsporidia, Unclassified / Q000145:classification / Q000235:genetics / Q000472:pathogenicity*; D009036:Moths / Q000382:microbiology*; D016818:Nosema / Q000145:classification / Q000235:genetics; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013172:Spores, Fungal / Q000145:classification / Q000235:genetics / Q000472:pathogenicity*
chemical_list: D061046:Biological Control Agents; D004271:DNA, Fungal