Efficacy of Pyriproxyfen for Control of Stored-Product Psocids (Psocoptera) on Concrete Surfaces

Abstract

The insect growth regulator pyriproxyfen was evaluated as a surface treatment for control of three stored-product psocid pests Liposcelis bostrychophila Badonnel, Liposcelis decolor (Pearman), and Liposcelis paeta Pearman (Psocoptera: Liposcelididae). Nymphs were exposed for 35 d on a concrete surface treated with 2.3 mg of active ingredient/m2 pyriproxyfen. Exposure to pyriproxyfen significantly reduced the numbers of both adults and nymphs in comparison with untreated controls. In adults, the greatest reduction (> 90%) was for L. decolor and L. bostrychophila, whereas for L. paeta it was 49%. Few adults of any species were found in the pyriproxyfen treatments. The greatest numbers of nymphs were recorded for L. bostrychophila for both pyriproxyfen treatments and controls. Few adults of any species were found in the pyriproxyfen treatments. The results indicate that pyriproxyfen is effective for control of L. bostrychophila, L. decolor, and L. paeta on concrete, and although complete control was not achieved, the results warrant further long-term study to determine whether pyriproxyfen can completely eliminate psocid populations over time.

Mobility of Stored Product Beetles after Exposure to a Combination Insecticide Containing Deltamethrin, Methoprene, and a Piperonyl Butoxide Synergist Depends on Species, Concentration, and Exposure Time

“…Our data show a temporary effect in adult movement, which may be desirable, as the inclusion of a neurotoxic agent along with methoprene slows down the exposed adults without terminating the exposure. As methoprene acts on the immatures, the inclusion of an adulticide, such as deltamethrin, is expected to cause adult mortality [24][25][26][27]. For instance, Athanassiou et al [28] used a combination of methoprene with natural pyrethrum, and found that all the exposed psocid individuals were dead in a very short interval, an effect that was apparently due to the presence of natural pyrethrum and not to methoprene.…”

Evaluation of the Entomopathogenic Fungi Beauveria bassiana, Metarhizium anisopliae, and Isaria fumosorosea for Control of Sitophilus oryzae

“…H ence, in a storage facility, the presence of areas with food, such as small food sources in cracks and crevices, may decrease the efficacy o f a given insecticidal application. This is likely to occur even if this food is treated w ith insecticide (4). O ur w ork clearly indicates that availability o f food m ay increase survival o f the exposed S. oryzae to entom opathogenic fungi.…”

Efficacy of a Combination of Beta-Cyfluthrin and Imidacloprid and Beta-Cyfluthrin Alone for Control of Stored-Product Insects on Concrete

“…Similarly, Toews et al (2010) reported that the presence of food affected mortality of T. confusum individuals after exposure to aerosols. Nevertheless, in a recent study, Athanassiou et al (2011) found that there was no clear effect of the presence of food on the efÞcacy of the insect growth regulator (IGR) pyriproxyfen on concrete for control of L. bostrychophila, L. paeta, and L. decolor (Pearman). Hence, knocked down individuals are not affected by the presence of food, and food plays a role only if these individuals are removed from the treated surface.…”

“…Psocids were found highly susceptible, given that mortality was 100% or close to 100% even before the termination of the 7-d interval. This is particularly important given that many psocid species are tolerant to a broad spectrum of insecticides with various modes of action (Nayak et al 1998(Nayak et al , 2005Athanassiou et al 2009bAthanassiou et al , 2010Athanassiou et al , 2011. Guedes et al (2008) found that L. bostrychophila and L. entomophila (Enderlein) were susceptible to beta-cyßuthrin on concrete surfaces, with L. bostrychophila being more tolerant than L. entomophila.…”