Effect of ultra violet irradiation (UVC) on biological parameters of Sitotroga cerealella (Olivier) (Lep., Gelechiidae)

Subject Areas : entomology and othea arthropods

S.  Moharramipour ¹ (Department of Entomology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran)
A. A.  Talebi ² (Department of Entomology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran)
R.  Sedaghat ³ (Department of Entomology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran)

Received: 2010-11-01 Accepted : 2011-04-12 Published : 2011-02-20

Keywords:

Abstract :

The Angoumoise grain moth, Sitotroga cerealella(Olivier), is a polyphagous and cosmopolitan species. This pest is distributed in Iran and all over the world. In this research, the effect of UV-irradiation was investigated on the biological parameters of S. cerealella. The 1, 2 and 3-days-old eggs were exposed to UV-irradiation (254 nm wavelength) for 0.5, 1, 2, 3 and 4 minutes at temperature of 27±3ºC, a photoperiod of 10: 14 (L: D) and 60±5% relative humidity. The results indicated that all exposure periods of UV-irradiation reduced percentage of hatching eggs. An increase in time of exposure to irradiation caused a gradual decrease in percentage of hatching in all age groups of eggs. It was observed that 2 and 3-days-old of S. cerealella eggs were more sensitive to UV-irradiation than 1-day-old eggs. Percentage of hatching eggs was 88.33% in control. However, hatching were inhibited up to 35.83, 3.33 and 18.33, respectively by 4 min exposure of 1, 2 and 3-days-old eggs of S. cerealella to UV-irradiation. At 2 and 3-days-old eggs, all exposure periods of UV-radiation increased significantly the incubation period of eggs of males and females in comparison to control. Adult longevity of females originating from 2 and 3 days-old treated eggs decreased significantly in comparison to control. However, in all age groups of eggs, no significant difference was observed between adult longevity of males in treated eggs and control.