African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12496

Full Length Research Paper

Toxic effects of Ricinus communis non-protein trypsin inhibitor on Spodoptera frugiperda (J. E. Smith) (Lepidoptera:Noctuidae)

Gislaine A. Carvalho*
  • Gislaine A. Carvalho*
  • Departamento de Entomologia, Universidade Federal de Vicosa, Vicosa, MG 36570-900, Brazil.
  • Google Scholar
Custódio D. dos Santos
  • Custódio D. dos Santos
  • Departamento de Quimica, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil.
  • Google Scholar
Dejane S. Alves
  • Dejane S. Alves
  • Departamento de Entomologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil.
  • Google Scholar
Geraldo A. Carvalho
  • Geraldo A. Carvalho
  • Departamento de Entomologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil.
  • Google Scholar
Maria das G. Cardoso
  • Maria das G. Cardoso
  • Departamento de Quimica, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil.
  • Google Scholar
Marcelo M. de Haro
  • Marcelo M. de Haro
  • Agricultural Research and Rural Extension Agency of Santa Catarina (EPAGRI/EEI), Itajai, SC 88034-901, Brazil.
  • Google Scholar


  •  Received: 24 March 2015
  •  Accepted: 08 October 2015
  •  Published: 26 October 2015

Abstract

In the study reported herein, we aimed to isolate a trypsin inhibitor from Ricinus communis leaves through chromatographic and spectrometric techniques and evaluate its toxic effects on the development of Spodoptera frugiperda larvae. Plant extracts were submitted to fractionation in adsorption column. The fraction 10, which showed the highest inhibitory activity, were incorporated into an artificial diet at the concentrations of 0, 0.06, 0.12, 0.25 and 0.5%, and offered to S. frugiperda larvae. Fresh weight of larvae, food consumed and weight of eliminated faeces were registered. Based on these parameters the following nutritional index were calculated: Relative Consumption Rate (RCR), Relative Metabolic Rate (RMR), Relative Growth Rate (RGR), Approximated Digestibility (AD), Efficiency of Ingested Food Conversion  (EIC), Efficiency of Digested Food Conversion (EDC) and the Metabolic Cost (100 - EDC). The inhibitor at 0.5% concentration was deleterious to S. frugiperda, extending the larval stage in 11 days, with higher RCR and ECD, and lower RGR, ECI and ECD. Therefore, the trypsin inhibitor from leaves of R. communis affected the S. frugiperda larval development, being promising in studies of alternative and sustainable control methods for lepidopteran pest species.
 
Key words: Castor beans, enzymatic inhibition, integrated pest management, plant defense against herbivory.
 

Abbreviation

RCR, Relative consumption rate; RMR, relative metabolic rate; RGR, relative growth rate; AD, approximated digestibility; EIC, efficiency of ingested food conversion; EDC, efficiency of digested food conversion.