Stored products insect pests

Mites are arachnids in the order Acari and should not be classified or referred to as insects. Mites are typically very small (about 0.5 mm) and have oval bodies with little or no differentiation of their two body regions. Over 50 species of mites have been found associated with stored products some feed directly on stored products, but others are predators, feed on fungi, or are parasites of other stored-product pests such as birds or rodents (Boczek, 1991). Mites can be important pests of stored food worldwide, but their economic importance varies considerably with location, commodity, and management practices. Some mite species can cause allergic reactions in... 

Direct behavioral evidence of how stored-product insects move among patches is limited, but what is available shows that stored-product pests readily leave patches of food, can find and exploit multiple patches, and that these processes are influenced by a variety of endogenous and exogenous factors. The time Cryptolestes ferrugineus spent in refugia has been shown to be influenced by strain, sex, and age (Cox and Parish, 1991 Cox et al., 1989, 1990). A variety of factors have been shown to influence the decision by red flour beetles to leave food patches, including insect density... 

The control of scale insects, whiteflies, plant hoppers, aphids, chinch bugs, phytophagous beetles, flies, caterpillars, masquitoes, and stored product pests costs more than one-half billion dollars annually in the United States alone. In the last decade great progress was made in the commercial production of microbial insecticides which can partially replace synthetically prepared insecticides. 

The following section reviews structures of pheromones that are biosynthesized from propanoate or clearly result from a mixed propanoate/acetate (methylmalonate/malonate) sequence. Several compounds showing corresponding carbon skeletons are known from various insect taxa, especially from ants and beetles.1 As some important stored-product pests use compounds like P7, P8, or Pll (see below), efforts have been made to use such compounds in IPM. Consequently, investigations covered (flight)behavior of the insects in the presence of pheromones and host odors771-773 as well as longevity, pheromone production, and... 

This method is suitable for stored-product pests. The evaluation of toxic vapor is a somewhat similar operation. The insecticide is introduced into a sealed container along with the insects and mortality is recorded at different intervals. Various fumigation techniques were described by Busvine (1971), including (1) small-scale techniques for measuring the susceptibility of exposed insects and (2) semipractical tests using large fumigation chambers. 

Magnesium silicate is used against juvenile and adult store product pests, exerting its lethal activity predominantly on juvenile and adult forms by sorption of the cuticular lipid layer, thus causing dehydration of the insects. 

Ethyl N-[2-(p-phenoxyphenoxy)ethyl]carbamate (Ro 13-5223, fenoxycarb, 56), a compound possessing high juvenile hormone activity, has gained practical importance in the control of various lepidopterous species, scale insects, fire ants and stored product pests (Fischer eta/., 1980 Masnere/a/., 1981 Dome/a/., 1981). It completely inhibits the population growth of the California red scale, Aonidiella aurantii in a concentration as low as 0.03%. It interrupts the development during morphogenesis and thus prevents eclosion of adults. 

Coleoptera. Sterol metabolism studies with another important stored products pest, the khapra beetle, Trogoderma granarium, revealed another phytophagous Insect that is unable to dealkylate and convert C28 and C29 phytosterols to cholesterol (23). Similar results were obtained whether a diet consisting of cracked wheat and brewer s yeast or an artificial diet coated with radiolabeled sterols was used (24). There was some selective uptake of cholesterol from tFe dietary sterols, as indicated by an enrichment of cholesterol in the pupal sterols 1.2% of total), compared to the dietary sterols (0.5% of total). Unlike the previously discussed stored product coleopteran pests, T. confusum and T. castaneum, both of which had high levels of 7-dehycTrochoiesterol, Tfo 7-dehydrocholesterol could be identified in the sterols from the khapra beetle. 

Larval development is so finely controlled, that the general belief has been that a minor disruption may result in a major effect for the insect. Disruption of the endocrine system for insect control was first proposed by Williams (19,20), Considerable attention has been paid to JH analogs (JHAs) for insecticidal use in the field. The JHAs have been exploited for control of a number of pest insects including stored product pests, fleas and mosquito larvae (21,22). 

Pyrethroids are used primarily for the control of household and agricultural insect pests, and secondarily in industrial, stored product, and veterinary applications. They are especially advantageous for use in northern climates because their toxicity is enhanced at low temperatures (Smith and Stratton 1986). Synthetic pyrethroid insecticides, including fenvalerate, are used as alternatives... 

Ramos-Rodriguez O, Campbell JF, Ramaswamy SB. Efficacy of the entomopathogenic nematode Steinemema riobrave against the stored-product insect pests Tribolium castaneum and Plodia interpunctella. Bio Cont. 2007 40 15-21. 

FIG. 1 Diagram illustrating the relationship between stored-product insect distribution and movement among resource patches, and the subsequent targeting of monitoring and pest suppression tools. 

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