2.1 Storage facilities
The storage facilities in which this study took place are located in Central Greece. The selection of these facilities was based on their size, the accessibility from University of Thessaly (UTH) personnel and the known historical presence of stored product insect species and other arthropods. The sampling was conducted in three types of storage facilities refereed as Facility 1, Facility 2 and Facility 3. Facilities 1 and 2 are pasta factories, with substantial quantities of soft and hard wheat, flour and bran, but also some barley and maize, while Facility 3 is a flour mill, mostly focused on soft wheat processing. The deployment of the traps on each facility was conducted at 18 June 2018, 4 July 2018, and 3 July 2018 for Facility 1, 2 and 3, respectively.
2.2. Traps, attractants and inspection
The trap types that were used in our experiments were Dome Trap (Trécé Inc., USA), Wall Trap (Trécé Inc., USA) and Box Trap (Insects Limited, Ltd., USA). These traps have been proven effective for monitoring purposes based on previous studies (Toews et al., 2009; Athanassiou and Arthur, 2018; Gerken and Campbell, 2021).
Four attractants (noted also as lures) were used in our experiments, which were 0.13 g: 1) PantryPatrol gel (gel, Insects Limited, Inc., USA), 2) Storgard™ Oil kairomone food attractant (oil, Trécé Inc.), 3) wheat germ (WG, Honeyville, USA), 4) Dermestid tablet attractant (bait, Insects Limited Inc., USA). Also, an additional series of traps was used without any attractant, and served as “control” (e.g., ctrl). In Facility 1, the different traps and attractant combinations were replicated two times. In Facilities 2 and 3, the combinations were replicated three times, based on larger space availability. For each Facility, the traps were inspected approx. every 15 days, with the exception of some intervals where access to the trapping areas was not possible (e.g. due to fumigations in certain areas etc.). The traps were rotated clockwise after each inspection. The attractants were replaced at 15-day intervals, while the traps were replaced whenever it was considered necessary (damaged or lost traps). All captured insects were transferred to the Laboratory of Entomology and Agricultural Zoology (LEAZ), Department of Agriculture, Crop Protection and Rural Environment, University of Thessaly.
The morphological identification of the captured individuals was carried out up to the species level, or lowest taxonomic unit, whenever this was possible using taxonomic keys, but in general many specimens are referred to as taxa. The insects found were classified into species (species identification) using different taxonomic keys (Bousquet, 1990; Peacock, 1993; USDA 1991).
rfb = red flour beetle
cfb = confused flour beetle
hfb = hairy fungus beetle
lgb = lesser grain borer
stgb = saw-toothed grain beetle
cb = cigarette beetle
rw = rice weevil
gw = granary weevil
imm = indianmeal moth
rgb = rusty grain beetle
trogoderma = dermestid genus