Total Lipid and Fatty Acid Composition in Male and Female Larvae of Indian-Meal Moth and Almond Moth (Lepidoptera: Pyralidae)

The total body lipid and fatty acid composition of last instar larvae of the Indian-meal moth, Plodia interpunctella, and almond moth, Cadra cautella, reared on a turkey mash diet was determined. Male P. interpunctella larvae contained significantly higher (lA-fold) total body lipid than females, while no differences between the sexes of C. cautella larvae were observed. The relative abundance of the fatty acids palmitate, palmitoleate, stearate, oleate, lineoleate, and linolenate was similar in both sexes of P. interpunctella and C. cautella. The accumulation of individual fatty acids in larvae of both the moth species did not correspond to levels of fatty acids in the diet. The accumulation of palmitate, palmitoleate, and oleate in moth larvae of both the species was greater than linoleate and linolenate, suggesting a sparing effect by the former on the latter, more unsaturated fatty acids

Malathion Resistance in Larvae of Some Southern Minnesota Populations of the Indianmeal Moth,\u3ci\u3e Plodia Interpunctella\u3c/i\u3e (Lepidoptera: Pyralidae), Infesting Bulk-Stored Shelled Corn

Larvae of 21 field collected populations of the Indianmeal moth, Plodia interpunctella, infesting stored shelled corn in southern Minnesota were tested for their susceptibility to malathion in the laboratory. A population that was a composite of the 21 populations and a malathion susceptible population were also tested for their susceptibility to malathion, pirimiphos-methyl and chlorpyrifos-methyl. Comparison of the LDso values of the field populations with the malathion susceptible population indicated that the field populations were ca. 33- to 625-fold resistant to malathion. The composite field population was ca. 243-fold resistant to malathion, and this population was 3.2-fold cross-resistant to pirimiphos-methyl, but was highly susceptible to chlorpyrifos-methyl

The Development and Use of Pitfall and Probe Traps for Capturing Insects in Stored Grain

The development and use of pitfall and probe traps for capture of insects in bulk-stored grain are outlined. Unbaited traps are effective in detecting infestations and they detect a large number of species compared with grain-sampling devices. The effectiveness of the traps is related to temperature, trapping period, and grain moisture content; and traps are less reliable for detecting insect species that are less mobile, have a non uniform distribution in grain, feed within kernels, or can escape from the traps. Comparisons are given between effectiveness of probe traps and grain sampling for detecting insects, and experience using probe traps in stored grain is reporte

Methyl bromide and sulfuryl fluoride effectiveness against red flour beetle life stages

The efficacy of methyl bromide (MB) and sulfuryl fluoride (SF) for managing all life stages of the red flour beetle, Tribolium castaneum, was investigated in the Hal Ross Flour Mill at Kansas State University. Eggs, young larvae, large larvae, pupae, and adults, confined in plastic compartments with dusting of flour and 2-cm deep flour, were exposed at 25 mill locations to two MB and two SF fumigations; in May and August 2009. MB and SF treatments were conducted by commercial fumigators, and each fumigation lasted 24 h. Gas monitoring lines were placed near the bioassay boxes to measure gas concentrations over time during fumigations. Both MB treatments killed 100% of all stages in the boxes except for large larvae in a few locations. In these locations, the mortality of large larvae ranged from 96-98%. SF treatments killed 100% of all stages except eggs. In the May treatment with SF, egg mortality ranged from 44-100% with only two boxes showing 100% mortality, because of under-dosing. Under-dosing occurred because the mill temperature was assumed to be greater than 27\ubaC when it was actually below 27\ubaC. In the second SF trial, only three boxes had egg mortalities that were less than 100%. However, data from the two replications showed that the mean mortalities of eggs and large larvae between MB and SF were not significantly different from each other

Susceptibility of Eggs and Adult Fecundity of the Lesser Grain Borer, Rhyzopertha dominca, Exposed to Methoprene

A series of tests were conducted to determine the susceptibility of eggs and neonates of the lesser grain borer Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae = Bostrychidae), exposed to the insect growth regulator, methoprene, on filter paper and on rough rice. In the first test, the hatch rate of eggs exposed on filter paper treated with methoprene at the label rate of 0.003 mg [AI]/cm2 when used as a surface treatment in structures was 52.0 ± 7.3% compared to 93.0 ± 3.3% on untreated controls. In the second test, eggs were exposed to a dose-response series of 0.00003 to 0.03 mg[AI]/cm2. Egg hatch was directly proportional to concentration and ranged from 85.0 ± 2.0% on untreated controls to 26.7 ± 8.3% at the highest concentration tested. In the third test, 1 ppm of methoprene was sprayed on long grain rough rice (paddy) (Cocodrie variety), and then individual kernels were cracked and an egg of R. dominica was placed directly on the kernel. On untreated rice kernels, 67.5 ± 11.6% of the eggs hatched and were able to bore inside, and all of these larvae emerged as adults. In contrast, 40.0 ± 5.3% of the eggs placed on treated cracked kernels were able to develop to where the larvae were visible through X-ray detection, but none emerged as adults. In the final test, newly-emerged adults were exposed on rough rice treated with 1 ppm methoprene. The number of eggs from adults on untreated rice was 52.1 ± 4.3 eggs per female, and on treated rice the average egg production was 12.5 ± 1.1 eggs per female. Methoprene applied on a surface or on rough rice affected development of egg hatch also reduced fecundity of parent adults exposed on the treated rough rice

Efficacy of ozone against stored grain insect species in wheat: laboratory and field observations

concentration of 0.43 or 0.86 g/m3 for 15-36 h or 4-30 h to estimate lethal time (LT) and lethal dose (LD, or concentration x time (Ct) product) to kill 99% of the adults at 28°C and 65% r.h. After ozone exposure adult mortality was counted daily for 5 d. At 0.43 and 0.86 g/m3, the LT99 values for adult mortality on day 1 were about 67 and 42 h, respectively. Corresponding LD99 values for adult mortality were 28 and 36 g-h/m3, respectively. On day 5, the LT99 and LD99 values decreased by 52 to 54% of day 1 values. Doubling the ozone concentration did not reduce the LT99 values by half. In general, the LD99 values on days 1 through 5 at an ozone concentration of 0.86 g/m3 were significantly greater than similar values at an ozone concentration of 0.43 g/m3. This suggested that R. dominica adults tend to be more susceptible when exposed for long time period to a low ozone concentration. In a bin holding 125 MT of hard red winter wheat, ozone was flushed through the grain mass for 5 d. Ozone concentrations at the plenum showed an increase from 0 to 0.107 g/m3. All adults of R. dominica; the rusty grain beetle, Cryptolestes ferrugineus (Stephens), Tribolium castaneum (Herbst), and eggs of the Indian meal moth, Plodia interpunctella (Hübner), in bioassays succumbed to ozonation. A laboratory strain and four phosphine-resistant field strains of the red flour beetle, T. castaneum, and a laboratory strain and two phosphine-resistant field strains of R. dominica were exposed to 0.43 and 0.86 g/m3 of ozone for 24 h. After one day of incubation following the 24h exposure, the mortality of the laboratory and phosphine-resistant field strains of both species was 100%

The Development and Use of Pitfall and Probe Traps for Capturing Insects in Stored Grain

The development and use of pitfall and probe traps for capture of insects in bulk-stored grain are outlined. Unbaited traps are effective in detecting infestations and they detect a large number of species compared with grain-sampling devices. The effectiveness of the traps is related to temperature, trapping period, and grain moisture content; and traps are less reliable for detecting insect species that are less mobile, have a non uniform distribution in grain, feed within kernels, or can escape from the traps. Comparisons are given between effectiveness of probe traps and grain sampling for detecting insects, and experience using probe traps in stored grain is reporte