Summary
Blattisocius tarsalis (Berlese) (Acari: Ascidae) is an effective predatory mite species on eggs of Mediterranean flour moth Ephestia kuehniella Zeller (Lepidoptera: Pyralidae). Mediterranean flour moth is an important pest of flour storages and mills in Turkey. The aim of this paper is to investigate the possibilities for the use of B. tarsalis as a biological control agent to control moth. The effect of different temperatures (15±1 ºC and 25±1 ºC) on development time of B. tarsalis at different food density levels (5, 10, 15 and 20 eggs densities) has been investigated. For 15 ºC; the development times of immature stages were 5,53 (1-6); 4,86 (3-5); 4,53 (0-5) and 4,86 (1-6) days while adults life span were determined 52,00 (3-67); 42,77 (5-67); 29,85 (1-66) and 27,36 (7-39) days for 5, 10, 15 and 20 moth egg densities. For 25 ºC the development times of immature stages were 5,00 (5-5) days at 10 prey eggs and 6,00 (6-6) days at the rest of prey densities, beside this life span of adults were determined 32,00 (20-39); 30,67 (15-40); 42,20 (10-64) and 38,67 (4-69) days at each food densities consequently. Fecundity and the consumption capacity of predatory mites have been carried out for each temperatures at different food densities. The duration of preovipositon, oviposition and postoviposition periods of B. tarsalis were also determined. The highest consumption of immature stages were determined (13,27 individuals/for development time) for 20 moth egg densities at 15 ºC, this value was observed at 10 moth egg densities for adults (172,8 individuals/duration of adult life span). The highest consumption of immature stages were determined (34,20 individuals /for development time) for 20 moth egg densities while this value was observed at 20 moth egg densities for adults (555,1 individuals /duration of adult life span) at 25 ºC.
Key words: Blattisocius tarsalis, Ephestia kuehniella, Biological control, Predatory mite
Anahtar sözcükler: Blattisocius tarsalis, Ephestia kuehniella, Biyolojik kontrol, Avcı akar
Introduction
Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) (Mediterranean flour moth) is the most abundant and primary pest species of cereals, flour, mills and other stored products. This moth causes 10 % of crop losses in Turkey (Esin, 1990; Çobanoğlu, 2002; Coşkuncu & Kovancı, 2005).
The protection of storage pests is mainly based on the use of traditional pesticides and residual insecticides. Among these the most preferred chemicals are phosphine and methyl bromide. Due to Montreal protocol, the using of methyl bromide will be banned completely in Turkey at 2007. The possibilities of methyl bromide alternatives have been investigated and biological control is considered as good alternatives for Mediterranean flour moth. The predatory mite Blattisocius tarsalis (Berlese) (Acari: Ascidae) is a common predatory mite of moth eggs in storages (Hughes, 1976; Haines, 1981; Hansen & Nielsen, 2001). However, many studies are known related to the biology of this predatory mite in the world (Haines, 1981; Hansen, 1998; Nielsen, 1998, 1999, 2001; Hansen & Nielsen, 2001). There was no information on the biology of this mite in Turkey.
We choose B. tarsalis because this predatory mite is very common in storages of Turkey (Özer et al., 1989; Çobanoğlu, 1996). The potential of B. tarsalis against Mediterranean flour moth has not been tested previously in Turkey. The goal of this study was to determine the reproductive potential, consumption capacity, developmental time of immatures and adult longevity of B. tarsalis on different prey egg densities.
