African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6849

Full Length Research Paper

Economic threshold level (ETL) of okra shoot and fruit borer, Earias spp. on okra

Sandeep Kaur
  • Sandeep Kaur
  • Department of Vegetable Science, Punjab Agricultural University, Ludhiana141 004, Punjab, India.
  • Google Scholar
Kulwinder Kaur Ginday
  • Kulwinder Kaur Ginday
  • Department of Entomology, Punjab Agricultural University, Ludhiana141 004, Punjab, India.
  • Google Scholar
Subash Singh
  • Subash Singh
  • Plant Clinic, Punjab Agricultural University, Ludhiana141 004, Punjab, India.
  • Google Scholar


  •  Received: 21 November 2013
  •  Accepted: 10 October 2014
  •  Published: 12 February 2015

Abstract

Shoot and fruit borer (SFB), Earias spp. is the second major pest on okra after cotton jassid under Punjab conditions. High incidence of this pest has been reported mainly in the pre- and post- rainy seasons. The farmers are using indiscriminate sprays of insecticide on this crop. Since crop is harvested on every alternate day, thus, insecticide residues on this crop are of great concern. Therefore to develop more safe and eco-friendly management strategies involving the application of insecticides at right time to reduce the use of insecticides on okra for the quality vegetable production; the present studies on “Economic threshold level (ETL) of shoot and fruit borer, Earias spp. on okra” were carried during the year 2009. Cumulative percent fruit infestation on the basis of fruit numbers and weight was found to be significantly lower in the first three ETLs (12.89-14.15 and 14.73-16.81%, respectively) than other ETLs (16.67-22.08 and 19.09-23.41%, respectively) standard check (20.14 and 22.67%, respectively) and control (23.13 and 24.22%, respectively). Marketable yield were significantly higher (95.49-96.17 q/ha) in the former three ETLs, that is, 20% shoot infestation (6 sprays), 2% fruit infestation (5 sprays) and 4% fruit infestation (5 sprays) in comparison to other ETLs (65.64-85.25 q/ha), standard check (67.73 q/ha) and control (64.19 q/ha). Significantly higher economic returns (Rs. 23059 - Rs. 23378/-) were also achieved from first three ETLs. The lower number of sprays, higher marketable yield and economic returns were obtained in the two ETLs, that is, 2 and 4% fruit infestation level. Keeping in view the development of resistance to the insecticides, it is desirable to start the spray at 4% fruit infestation which will provide sufficient protection against pest.  

 

Key words: Determination, economic threshold level (ETL), shoot and fruit borer, Earias spp., okra.