Efficacy of gaseous ozone at high concentrations against Plodia interpunctella (Hubner) and Ephestia cautella (Walker) in Almond


IŞIKBER A. A., Oztekin M. S., DAYISOYLU K. S., Duman A. D., Eroglu S.

TURKIYE ENTOMOLOJI DERGISI-TURKISH JOURNAL OF ENTOMOLOGY, vol.39, no.2, pp.187-198, 2015 (SCI-Expanded) identifier identifier

Abstract

In this study efficacy of gaseous ozone at high concentrations and short exposure time against all life stages of Plodia interpunctella (Hubner) ve Ephestia cautella (Walker) (Lepidoptera: Pyralidae) in almond was investigated under laboratory conditions. All life stages of E. cautella and P. interpunctella placed at the top and bottom position of 1.3 kg almond in fumigation chamber were exposed to two different concentrations (8.35 and 33.33 mg/l) of ozone flush treatment at 30 minute intervals for 6 hour. The results of biological tests indicated that ozone treatment at 33.33 mg/l concentration resulted in % 100 or nearly % 100 mortalities of only adult and pupa stage of E. cautella and all life stages of P. interpunctella placed at top position of the almond. However, ozone treatments at lower concentration (8.35 mg/l) caused nearly % 100 mortalities of only adult and pupa stage of P. interpunctella at placed at top position of the almond. It was clear that ozone treatments at low concentration (8.35 mg/l) resulted in significantly lower mortalities of all life stages of E. cautella and P. interpunctella than those at high concentration (33.33 mg/l). Generally, in all ozone treatments the mortalities of tested insects placed at top position of the almond were higher than those placed at bottom position of the almond. Notably, it was hard to kill the larvae and eggs of E. cautella and P. interpunctella placed at bottom position of the almond. Moreover, it was found that E. cautella was more tolerant to ozone treatments than P. interpunctella except their egg stage. In conclusion, this study shows that ozone treatment at high concentrations and short exposure time could not be effective alternative to methyl bromide for the rapid disinfestations of the almonds since it did not cause the complete mortality of all life stages of E. cautella and P. interpunctella on almond.