The influence of the type of storage on pest infestation of stored grain in the Czech Republic

Abstract

Stored-product pests cause high economic losses by feeding on stored grain and endanger the public health by contamination of food by allergens. Therefore, the aim of this work was to explore whether the risk of infestation of stored grain by pests is different in various types of storage premises. We compared the level of infestation and the pest species composition in the two main types of grain stores in Central Europe that includes horizontal flat-stores (HFS) and vertical silostores (elevators) (VSS). A total of 147 grain stores located in Bohemia, Czech Republic was inspected. We found that both types of stores were infested with arthropods of three main taxonomic groups: mites (25 species, 120 000 individuals), psocids (8 species, 5 600 individuals) and beetles (23 species, 4 500 individuals). We found that VSS and HFS differ in species composition of mites, psocids and beetles. However, the primary grain pests (i.e. Lepidoglyphus destructor, Acarus siro, Tyrophagus putrescentiae, Lachesilla pedicularia, Sitophilus oryzae, Rhyzopertha dominica, Oryzaephilus surinamensis and Cryptolestes ferrugineus) occurred in both types of stores. The only exception was higher frequency and abundance of two serious beetle-pests (Tribolium castaneum, Sitophilus granarius) in HFS than in VSS. The total numbers of mite and beetle species infesting VSS and HFS was almost the same. There was higher psocid species diversity in VSS than in HFS. The difference between the total (i.e. level of pest infestation per kg of grain sample) numbers of mite and psocid individuals collected from VSS and HFS was not significant. However, the total numbers of beetle-pest individuals collected from HFS was twice the amount collected from VSS. We concluded that both types of stores are equally risky in terms of mite and psocid infestation. HFS is more risky for grain storage than VSS in terms of beetle infestations, although even the VSS structures cannot be in no way called pest-safe. The VSS and HFS microclimatic conditions (humidity, temperature) are discussed in relation to mite, psocid and beetle infestation.Keywords: food; grain; storage; silo; bulk stores; pests; mites; psocids; beetles Production of grain-crops at the farm level is a valueadded agricultural process that includes both field planting and storage of grain. The economical outcome of this process is influenced by many biotic and abiotic factors and their mutual interactions. Infestation of grain by arthropods belongs among the most economically important biotic factors; since these pests cause enormous losses of stored products each season worldwide (Subramanyam and Hagstrum 1996). The type of storage technology is considered a serious abiotic factor influencing the stored-grain quality. Industrial buildings differ in their level of isolation to prevent colonisation by outdoor pests (Murphy and Todd 1993). For example, Mann et al. (1999) found that adults of Cryptolestes ferrugineus were unable to infest wheat grain stored in sealed metal bincontainers. It is also...

A review on the factors affecting mite growth in stored grain commodities

“…Moisture concentration may also occur in the corners of some storage facilities leading to a high mite aggregation rate (Athanassiou et al 2001(Athanassiou et al , 2005. Stejskal et al (2003) found that the type of storage structure had little effect on mite infestations, with horizontal flat and vertical silo stores equally at risk, presumably to due to the inability to control surface moisture absorption, even in aerated bulks.…”

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The toxicity of bean flour (Phaseolus vulgaris) to stored-product mites (Acari: Acaridida)

“…Stored-product mites are abundant and frequent pests in cereal stores in the Czech Republic (STEJSKAL et al 2003), UK, Canada and other countries. The main injurious aspect of these mites is the production of allergens that cause hypersensitivity not only in those who work with stored grain such as farm workers, millers and bakers, but they also seriously endanger the health of the general population (ARLIAN 2002).…”

Entomopathogenic Nematodes (Nematoda: Rhabditida) in Slovenia: From Tabula Rasa to Implementation into Crop Production Systems

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