Efficacy assessment of diatomaceous earth against <i>Callosobruchus maculatus</i> (F.) (Coleoptera: Bruchidae) on gram at different temperature and relative humidity regimes

  • W. Wakil Department Of Agricultural Entomology, University Of Agriculture, Faisalabad, Pakistan. Email: waqaswakeel@hotmail.com
  • M. U. Ghazanfar Plant Pathology, College Of Agriculture, D.G. Khan, Sub-Campus University Of Agriculture, Faisalabad, Pakistan
  • M. Ashfaq Department Of Agricultural Entomology, University Of Agriculture, Faisalabad, Pakistan
  • K. Ali Department Of Agricultural Entomology, University Of Agriculture, Faisalabad, Pakistan.
  • T. Riasat Department Of Agricultural Entomology, University Of Agriculture, Faisalabad, Pakistan.

Abstract

The efficacy of diatomaceous earth against Callosobruchus maculatus (Coleoptera: Bruchidae) was evaluated on stored gram under laboratory conditions. The bioassay was conducted at 25 and 30°C in combination with 50 and 60% r.h. Diatomaceous earth (DE) formulation (Diafil 610), at the dose rates of 200, 400, 600 and 800 ppm was admixed with gram grains. Fifty unsexed adults of C. maculatus were released in each jar and treatments replicated thrice. Mortality data was recorded after 2, 3 and 5 days of exposure intervals and after every count the dead individuals were removed, and the commodity was maintained for an additional period of 25 d, in order to record the emergence of F1 adults. The results showed that all treatments were highly effective against the bruchids; however, the highest mortality (100%) was observed at 30°C and 50% relative humidity at 800 ppm of DE with minimal progeny production.

Keywords: Diatomaceous earth, Callosobruchus maculatus, Temperature, relative humidity, Gram
Veröffentlicht
2010-09-20
Rubrik
Section: Residual Insecticides - Synthetic and Botanical