title: Evaluation of alternative Plutella xylostella control by two Isaria fumosorosea conidial formulations - oil-based formulation and wettable powder - combined with Bacillus thuringiensis.
abstract: BACKGROUND
  Entomopathogenic fungi are potential candidates for controlling the diamondback moth Plutella xylostella (L.) (Lepidoptera: Plutellidae). The control efficacy of two Isaria fumosorosea conidial formulations - wettable powder and oil-based formulation - combined with Bacillus thuringiensis against P. xylostella was tested.
  
  
  RESULTS
  In the laboratory, the combined application of two pathogens increased larval mortality either in an additive or a synergistic way. P. xylostella larvae treated with oil-based formulation died sooner than larvae infected with wettable powder. For pot and field experiments, each formulation was applied alone or combined with B. thuringiensis 668 µg mL(-1) , and then larval mortality, pupation rate, adult emergence rate, female longevity and fecundity were recorded. In pot experiments there was no evidence of any antagonistic effects between the two pathogens. Combined application of B. thuringiensis and a high concentration of the two I. fumosorosea formulations resulted in higher mortality (84.4 and 86.2%) with minimum pupation (15.6 and 11.9%) and adult emergence rates (8.7 and 7.0%). Female longevity and fecundity were significantly reduced by the two formulations at high concentration compared with the control. Similar results were also observed in field experiments.
  
  
  CONCLUSIONS
  The combined application of I. fumosorosea and B. thuringiensis is a promising alternative strategy for P. xylostella control. © 2015 Society of Chemical Industry.
authors: College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong, China.
authors: Xiao-Ge
authors: http://orcid.org/0000-0001-6341-6431
authors: XG
authors: Nian
authors: College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong, China.
authors: Yu-Rong
authors: YR
authors: He
authors: Plant Protection Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong, China.
authors: Li-Hua
authors: LH
authors: Lu
authors: College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong, China.
authors: Rui
authors: R
authors: Zhao
mesh_terms: D000818:Animals; D001413:Bacillus thuringiensis; D005260:Female; D005298:Fertility; D006999:Hypocreales / Q000502:physiology*; D007306:Insecticides; D007814:Larva / Q000254:growth & development / Q000382:microbiology; D008136:Longevity; D008297:Male; D009036:Moths / Q000254:growth & development / Q000382:microbiology*; D010572:Pest Control, Biological / Q000379:methods*; D010938:Plant Oils; D013172:Spores, Fungal
chemical_list: D007306:Insecticides; D010938:Plant Oils
keywords: Bacillus thuringiensis; Isaria fumosorosea; Plutella xylostella; additive and synergistic effects; biological control; formulation