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Khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae) is one of the major insect pests of stored products in hot and dry regions of the world. Being a non-selective feeder, the larvae of this species feed on a wide range of hosts, particularly cereal grains and cause significant damage and health risk. It is commonly found in Asia and Africa, and is a regulated/quarantine pest for much of the rest of the world. Countries housing this species are facing trade restrictions on their products by non-khapra countries, causing them considerable economic losses. This species is more difficult to identify and control than other stored grain insect pests. In this context, this article has been written, which deals with the identification of this species, loss and economic impacts with some case studies, and management tactics, which would bestow handy/helpful information to farmers and bio-security experts for the control of this species in storage and quarantine.

The present study was conducted to probe out the nutritive losses caused by Rhyzopertha dominica (F.) and Trogoderma granarium (Everts) were quantified in six rice genotypes (KSK-434, KSK-282, Irri-6, Shaheen basmati, Basmati 385 and Chenab basmati). Percent crude protein, ash and moisture content were measured for qualitative losses, while for quantitative losses, frass weight and weight loss were examined after infestation period of 90 days of. Highest weight losses (25.76%) and (15.37%) were observed in KSK-434 by infestation of R. dominica and T. granarium, respectively, compared with un-infested grains after a storage period of 90 days. Highest frass weight (8.57 g) was recorded for KSK-434 while relatively low frass weight (4.16 g) was recorded for Basmati 385 by infestation of R. dominica. Relatively low frass weights of 5.67, 4.46 and 4.01 g were recorded in KSK-434, Chenab basmati and Shaheen basmati, respectively by attack of T. granarium. Highest percentage moisture values (14.03 and 11.24%) were recorded for KSK-434 by infestations of both test insects compared to non-infested (controls). Percent crude protein was decreased (from 6.97% to the 4.92%) due to infestation of R. dominica values by strain were KSK-434 (4.54%), Shaheen basmati (4.89%) and chenab basmati (4.92%). In the case of T. granarium infestation, almost all the varieties sustained the low protein contents except KSK-434 (5.02%) and Basmiti 385 (5.17%) and Shaheen basmati, protein contents loss comparable to non-infested control (7.09%). Ash content was high in genotype KSK- 282 (0.68 %) compared to control. KSK-434 and Chenab basmati had relatively low ash percentage due to high infestation of T. granarium. R. dominica attack produced the highest percent ash content (0.66%) in KSK-282 and the least (0.44%) in KSK- 434. The tested rice genotypes were more susceptible to R. dominica than T. granarium among the different genotypes of selected cereals.

In this study four types of inert dusts were mixed with wheat grains at three concentrations 5, 7 and 9 gm/kgm of wheat to estimate their effect on some biological aspects of Khapra beetle Trogoderma granarium Everts. These inert dusts are Chalky limestone, Bituminous limestone, Sand and Celite. The results indicated that these inert dusts affected on some biological aspects of this insect, present results showed that the inert dusts caused death to larvae and pupae during its growth and development, and this led to reduce the number of insects, mortality rate of larvae increased to 46.64, 55.56, 27.78 and 87.78% for Chalky limestone, Bituminous limestone, Sand and Celite , respectively, as compared to 0.0% for the control. Also mortality rate of pupae increased to 15.02, 23.89, 3.69 and 27.77%, respectively, as compared to 0.0% for the control. This inert dusts led to significant increase of the larval period whereas were 30.05, 31.69, 27.41 and 33.85 day, respectively, as compared to 24.07 day for the control. Also inert dusts led to significant decrease of the emerging adults number whereas were 4.56, 3.56, 6.44 and 2.67 insect, respectively, as compared to 10.0 insect for the control, also inert dusts led to significant decrease of the laid eggs number whereas were 16.56, 16.44, 20.89 and 17.67 egg/ female, respectively, as compared to 34.67 egg/ female for the control.

The khapra beetle, Trogoderma granarium, is an important quarantine pest of stored-products. While it is not established in the North America, frequent interceptions highlight the need for treatments to eradicate isolated populations if they occur. Methyl bromide has long been the standard fumigant used for this purpose; however, increasing restrictions on its use necessitate the development of new treatment options. Here we evaluate a treatment for khapra beetle using a combination of sulfuryl fluoride (SF) and propylene oxide (PPO). Experiments were conducted to determine the most tolerant stages and the effective rates for each compound. Combination treatments using both products were then evaluated at several temperatures to determine effective doses for quarantine level control. The egg stage was by far the most tolerant to SF, requiring concentration × time (CT) products roughly 10-fold greater than the next most tolerant stage, diapausing larvae. Diapausing larvae were significantly more tolerant to SF than non-diapausing larvae in a recently collected ‘field’ strain, but not in a more than 30-yr-old ‘laboratory’ culture. PPO treatments were shown to completely control the egg stage at CTs greater than 155 hr-mgL-1 at both 10 and 20°C. Resulting combination treatments with initial dose rates of 96 and 40 mgL-1 at 10°C and 80 and 40 mgL-1 at 20°C are proposed for SF and PPO, respectively. These combination treatments utilize SF’s efficacy against the larval stage along with PPO’s superior ovicidal properties to provide enhanced treatment efficacy over each product alone against all life stages of khapra beetle.

Groundnut production has been reported to be threatened by storage insect pests which caused significant damage in storage. The repellent and efficacy activities of Citrus sinensis leaf extract were assessed on Trogoderma granarium in stored groundnut. The treatment was laid in a Completely Randomized Design with 3, 5, and 7% concentration level of methanolic and petroleum ether Extract for insecticidal activities. The results of C. sinensis leaf extract toxicity obtained was significant at 7% concentration at 24, 48 and 72 hours after treatment with 100% and 80% mortality in methanolic and Pet. ether extracts respectively in adults. Half disc experiment was carried out to determine the repellency activities with 1, 2, and 3% concentration of methanolic and pet. ether extract. It was observed that at 2HAT the insects moved towards the extract with the Index of Repellency of 1.13 at 3 % concentration for methanolic and pet ether extract, as the hours increase from 4 to 6HAT it was observed that the extract acted as repellant towards the insect with methanol and petroleum ether extract of 3 % concentration having the highest repellency index of 0.47. Petroleum ether at 1 % concentration with the value of 1.47, 1.40 and 1.20 repellency index across the 2, 4 and 6HAT showed that the extract remains an attractant towards T. granarium. The results obtained from this study is an indication of the potential of methanolic and petroleum ether crude extract of C. sinensis in groundnut storage

Combined action of various inert dusts (diatomaceous earth DE and zeolite) and microbial insecticides (abamectin and spinetoram) was evaluated against Trogoderma granarium Everts at Grain Research Training and Storage Management Cell, department of Entomology, University of Agriculture, Faisalabad, Pakistan during the year 2018–19. Doses were 750 ppm in case of inert dusts and 1 ppm in case of insecticides. Efficacy was checked on wheat, rice and maize at three different temperatures (15, 25 and 35 °C) and two relative humidity levels (55 and 75%). Mortality data was taken 1, 3, 5 and 7 days after treatments. Factorial under Completely Randomized Design was used for analysis. In all combinations tested, complete mortality (100%) of the insects was achieved at 35 °C + 55% R.H. after 14 days of exposure. But in general, mortality was higher at increased temperature and decreased R.H. With an increase in exposure period, mortality was also increased. Wheat was most susceptible as compared to rice and maize regarding the mortality of insects except in cases of 100% mortality. Results suggested that both DEs and zeolites can be combined with insecticides in order to achieve complete control of this specie but certain factors like dose, temperature, R.H., commodity and exposure time are important in affecting their efficacies which should be kept in mind for the integrated control of this insect. This is first report in which zeolite is used in combination with insecticides against Trogoderma granarium.

Trogoderma granarium Everts (Coleoptera: Dermestidae) is one of the most important quarantine pests of stored grains. Control of this insect species can be achieved through a gaseous insecticide, phosphine. Many studies focus on the effect of phosphine on different developmental stages of insects, with most of them highlighting eggs as the most tolerant stage. Our data showed that 2-d-old eggs of T. granarium are more susceptible than 1-d-old eggs. Faster hatching was observed in eggs exposed to phosphine for 2 d compared to controls and the result was more pronounced for 1-d-old than 2-d-old eggs. In contrast to the 2-d exposure, hatching rates of eggs exposed to 4 and 6 d were notably reduced, while there was a delay in egg hatching compared to controls. Moreover, larval development from untreated eggs was faster than the larvae from treated eggs, regardless of the exposure time. These dissimilar patters in larval growth may suggest certain delayed effects of phosphine fumigation. The results of the present work can be further utilized for the development of phosphine-based quarantine and pre-shipment treatments for the control of T. granarium.

The botanical substances constitute valuable alternatives to synthetic insecticides. In the last decades, numerous substances of natural origin have been tested against stored-product insects, mostly as fumigants or for contact toxicity, while there is limited knowledge on the efficacy of plant secondary metabolites if used as grain protectants. In the present study, we evaluated the lethal activity of 2-undecanone, acetic acid, trans-anethole, furfural, (E)-2-decenal and (E, E)-2,4-decadienal as wheat protectants for the management of larvae and adults of two important storage pests, Tenebrio molitor (Coleoptera: Tenebrionidae) and Trogoderma granarium (Coleoptera: Dermestidae). 2-undecanone caused 98.9% mortality to the exposed T. molitor adults at 1000 μl/kg wheat 7 days post-exposure, while acetic acid and furfural followed providing 94.4% and 92.2% mortality respectively. 2-Undecanone and (E)-2-decenal caused the highest mortalities to T. molitor larvae (i.e., 87.8% and 80.0% respectively) exposed to 1000 μl/kg wheat for 7 days. All T. granarium adults were dead at 1000 μl (E)-2-decenal or acetic acid/kg wheat 5 or 7 days post-exposure respectively. Complete (100%) mortality was assessed for larvae exposed to (E, E)-2,4-decadienal and (E)-2-decenal at 1000 μl/kg wheat after 4 and 6 days respectively. Our findings report for the first time that 2-undecanone, (E)-2-decenal, and (E, E)-2,4-decadienal are effective new candidate control agents of different developmental stages of T. molitor and T. granarium.

Globally, there are growing concerns about the overuse of synthetic insecticides to their subsequent damage to the environment and mammalian. Therefore, developing new and safe eco-friendly insecticides based on natural products, such as essential oils,is considered a substitute for chemical pesticides in pest control.In the present study,mimicry the storage environment for grain products stored in a small scale by surface treatment method to determining the lethal and effective concentrations for three chemical insecticides (Imidacloprid, Zeta-cypermethrin and Lufenuron) and three essential oils (Citrus bergamia, Citrus limon and Cuminum cyminum) against larvae of Trogoderma granarium at various concentrations and time intervals.Results revealed that the C. bergamia EO exhibited high larvacidal activity compared to the other two oils, i.e.,30.36% after 24h of exposure at the higher concentration (10 v/v), while after 72h of exposure at the same,mortality reached 75.33%. Concerning chemical insecticides, the imidacloprid insecticides at all tested concentrations were the most effective against T. granarium larvae, leading to 40% mortality at the lower concentration (1v/v) after 24h. of exposure, and 96.66% mortality at the higher concentration(10 v/v)72h. post-exposure. Whereupon, C. limon oil had significantly higher LC50 and LC99 values than other oils, indicating that C. bergamia oil was more toxic against T. granarium larvae than to both oils. In contrast, LC99 values of Lufenuron were the highest significantly being about 1.61 and 2.31 times compared to Zeta-cypermethrin and Imidacloprid at the maximum concentration tested after 72h of exposure, respectively.In sum,our research focuses on the potential of selected EOs as a suitable substitute for chemical pesticides against this noxious species.

In this study, we evaluated the susceptibility of four different sorghum varieties to infestation by the khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae), as compared with wheat, which served as a ‘control’ commodity. In population growth assays, there was preference for population development on wheat compared to the different sorghum varieties. In contrast, there were no significant differences in total population development among the four varieties of sorghum. However, the proportion of immature stages (larvae, pupae) in relation to the adult stage varied significantly among the different varieties. Moreover, significant differences were noted among the commodities tested regarding the final weight decrease, as well as the amount of frass and kernel damage. Our study clearly demonstrates noticeable differences in the susceptibility of the varieties to T. granarium infestation. These results show that this species can develop on different varieties of sorghum, and variety selection should be further considered in a host-plant resistance-based management program for T. granarium.

We investigated the extent and pattern of damage in wheat caused by Tribolium castaneum Herbst (Coleoptera: Tenebrionidae), Trogoderma granarium Everts (Coleoptera: Dermestidae) and Rhyzopertha dominica F. (Coleoptera: Bostrichidae) over a period of 75 d. Damage parameters included numbers of damaged grains, their weight; numbers of undamaged grains, their weight; frass weight and percent weight loss. Results showed after 75 d, maximum damaged grains were 125.17 ± 22.88 by R. dominica followed 80.50 ± 6.91 by T. granarium and least were 20.00 ± 2.61 after 50 d by T. castaneum. For R. dominica and T. granarium damage to grains increased with time (P 0.05). Maximum percent weight loss was 7.02 ± 1.87 g by R. dominica followed by 2.89 ± 0.33 g by T. granarium and least 0.65 ± 0.08 g by T. castaneum. Maximum dead insects percentage was 82% after 25 d for R. dominica, 59.67 ± 3.44 for T. granarium after 50 d and 100.00 ± 0.00 for T. castenum after 50 or 75 d compared to other time periods (P

Khapra beetle, Trogoderma granarium Everts is a serious pest that affects stored grains and oilseeds. The current work was carried out to investigate the effect of malathion sublethal concentrations (LC10 and LC40) exposed to first and fourth larval instars on biological aspects and population growth of T. granarium. Results indicated that exposure of 1-st instar to either LC10 or LC40 had a destructive effect and treated larvae failed to complete their larval stage. While 4-th instar exposed to the same sublethal concentrations completed their life cycle with considerable impacts on biological aspects and life table parameters. Treatments increased the number of instars molting reaching seven or eightinstars. In contrast, larval, pre-adult, and total longevity periods were decreased in treatments compared with control. Concerning life table parameters such as net reproductive rate (R0), intrinsic rates of increase (r), finite rate (λ), fecundity and mean generation time (T) were decreased compared to control. The current study clarified thatsublethal concentrations of malathion induce strong adverse effects and suppress the population growth of T. granarium. Our results would be useful to assess the overall effects of malathion on T. granarium and can contribute effectively in pest management.

Studies on residual efficacy of insecticides with reduced risk are necessary for strategies on their use and application frequency. Within these insecticides, insect growth regulators, such as pyriproxyfen, have been successfully used to control stored grain pests. The objective of this study was to evaluate the residual efficacy of pyriproxyfen in larvae of the stored grain pests Oryzaephilus surinamensis, Tribolium castaneum and Trogoderma granarium. Grains of wheat, maize, rice, and oats were exposed to pyriproxyfen at concentrations of 1, 2 or 4 mg kg−1. Six bioassays were performed by releasing the insects on treated grains after different post treatment periods (0, 2, 4, 8, 12 and 16 weeks). Adult emergence of the three insect species was reduced at tested concentrations in all treated grains. For all bioassays the residual efficacy of pyriproxyfen decreased with increase in the post treatment period. At 4 mg kg−1, the adult emergence did not exceed 16% at week 0 and it was

Insect meal is a new agricultural commodity that will be produced in huge quantities in the near future and will be treated as all traditional agricultural commodities, i.e., insects will be harvested, processed, transported and stored. As most agricultural commodities, insect meals may be prone to insect infestations during their “post-harvest stages.” However, no information is available at the moment on the susceptibility of insect meals to stored-product insect infestations. The objective of the present study was to evaluate the susceptibility of Tenebrio molitor larvae-meal to insect infestations during storage. Specifically, we investigated the population growth of major stored-product insects, i.e., T. molitor, Tribolium confusum, Alphitobius diaperinus and Trogoderma granarium on T. molitor larvae-meal, as well as on T. molitor meal-based substrates with different percentages of wheat bran (0, 25, 50, 75, 90, 95 and 100%). Our results show that T. molitor and T. confusum can infest 100% T. molitor meal and develop significant populations on this substrate. However, the speed of growth of both species in 100% T. molitor meal was considerably lower compared to the substrates that contained also wheat bran. In contrast, A. diaperinus and T. granarium did not grow at all on 100% T. molitor meal and both exhibited poor growth on the substrate containing 75% insect meal. In general, our results show the susceptibility of T. molitor larvae meal, as well as T. molitor meal-based substrates with different percentages of wheat bran, to infestations by major stored-product insects. To our knowledge, this is the first study on the susceptibility of insect meals to insect infestations.

The results of food kind exposed to radiation exhibited a different mean mortality on adults reached 52.41 ,58.70 ,50.37 and 52.41% and for percent egg hatch reached 12.96 ,17.78 ,18.33 and 18.33% while the mean mortality in larvae reached 45.56 ,46.48 ,41.30 and 38.15%, and the percentage of pupae transformation to adults reached 47.96 , 46.80 , 45 ,43.52%.Results were positively proportion with increasing the energy levels reached 22.08 , 64.86 , 65.14% for larvae , while the mean percentage of eggs hatchling and the means percentages of pupae transformation to adults decrease with increasing energy levels reached 23.61 , 17.66 and 10.28% for egg hatching , and 58.61 , 40.31 and 29.17% for pupae transformation .The means of adults and larvae mortality increase with increasing the exposure period to radiation reached 31.39 , 58.06 , 72.78 , 75.83 and 76.94% , and 21.67 ,41.39 ,54.72 ,64.44 and 74.17% respectively. Means of eggs hatching percentage and pupae transferred to adults were proportionally decrease with increasing the exposure period. Also the storage of bags affected on mortality of adults Khapra beetle , which reached in bags 5.83%. Compared without bags reached zero, and the mean percentage of eggs hatching in bags treatment decrease reached 31.67% compared without bags reached 100%. While it was no differences in the larvae mortalities of both treatments . Also the pupae transferred to adults were proportionally decrease in bags treatment reached 89.17% compared in controlling without bags reached 100%.

The residual efficacy of novaluron on concrete, metal and wood was evaluated against last-instar larvae of Oryzaephilus surinamensis (L.), Triboliumcastaneum (Herbst), and Trogoderma granarium Everts. The larvae and food provided for survival were exposed to surfaces pretreated at rates of 0.053, to 0.209 mg/m2 and bioassays were conducted from 0- to 16-weeks post-treatment. Percentage emergence of adults was recorded after 30 days (d). On all surfaces at week 0, no O. surinamensis or T.castaneum adults emerged, and &le, 3.3% emergence of T. granarium was found at 0.209 mg/m2. Novaluron significantly reduced the percentage emergence of adults of the three species compared to a distilled water control for the first 12 weeks on all the tested surfaces as the residual efficacy declined at a low rate during initial weeks and then at a high rate in the final weeks of the 16-week study. Reductions to emergence were most persistent on metal surfaces, with mean percentages of adult emergence of &le, 18.3 in week 12, followed by concrete (&le, 32.5) and wood (&le, 45.0) for all species at novaluron application rates of 0.209 mg/m2. For &gt, 4-weeks protection, higher application rates would be needed to avoid buildup of pest populations and reductions in profitability. Such results can be helpful for the management of O. surinamensis, T.castaneum, and T. granarium as the costs of commonly used insecticides against postharvest insect pests and the resistance of these insects to the pesticides gradually increase in mills, warehouses, and food storage facilities.

The invasive khapra beetle, Trogoderma granarium, is an economically destructive species and the only stored product insect pest that is quarantined in the USA. In the past several decades, there have been an increasing number of interceptions of T. granarium at ports in the USA. The established trap and lure used for surveillance of T. granarium in high risk areas was developed 30 years ago, but since then new lures containing food and/or pheromonal stimuli have become available. In the USA, researchers must work with it in an approved quarantine facility, which slows research and development into mitigation strategies for the species. However, there are closely related dermestids already in the USA but not under quarantine, such as Trogoderma variabile, which may be able to act as a surrogate species for the behavioral responses of T. granarium. Thus, we evaluated the attraction to, arrestment by, and preference between different semiochemical stimuli for immature life stages of both these species and determined whether T. variabile could serve as a surrogate species for T. granarium. While all lures showed some positive response in each of the assays, lures with food cues and pheromones together exhibited the most consistent positive response by larval T. granarium. However, the behavioral response of T. variabile was not consistently correlated with that of T. granarium. Our study contributes updated data that can be used by biosecurity experts in developing surveillance programs for T. granarium.

Simple Summary The khapra beetle is defined as one of the most important quarantine pests globally, and fumigating by methyl bromide, one of the ozone-depleting substances under the Montreal Protocol, is a routine measure used for phytosanitary treatment. To protect the Ozone layer, an environmentally friendly measure is needed to be developed. The middle- to late-stage larvae and adults were treated with irradiation, modified atmosphere (MA) alone, and their combinations at room temperature of 24–26 ℃. As a result, late-stage larvae are determined as the most tolerant stage. Ionizing radiation was used to enhance the effects of 1% and 2% O2 MA treatments that the obvious synergistic effects are presented in all combinations, resulted in saving as high as 60% of the estimated exposure times comparing with MA treatment alone. A total of 111,366 late-stage larvae were exposed to a 1% O2 atmosphere for 14 or 15 days after a 200 Gy irradiation, resulted in no survivor in the validating tests. Therefore, the MA-irradiation combination treatment can provide quarantine security at a very high level, it may be combined with international transportation (train or sea container) to disinfest the commodities infested by khapra beetle and other stored products insect pests. Abstract The khapra beetle, Trogoderma granarium Everts, is defined as one of the most important quarantine pests globally, and fumigation with methyl bromide, an ozone-depleting substance, is a common phytosanitary measure currently used. The modified atmosphere (MA), irradiation, and their combination treatments of T. granarium larvae and adults were performed at room temperature (24–26 ℃) to develop an ecofriendly phytosanitary disinfestation measure and to shorten the exposure time and overcome treatment disadvantages of irradiation. Late-stage larvae are determined as the most tolerant stage resulted in large LT99.9968 values of 32.6 (29.2–37.5) and 38.0 (35.1–41.7) days treated under 1% and 2% O2 (with N2 balance) atmosphere, respectively. Ionizing radiation was used to enhance the effect of MA and the mortality was highly significantly affected by all the interaction effects, indicating that the synergistic effects present in all the combined treatments. The synergistic ratios, which is defined as the estimated lethal time for MA treatment (LD90, LD99, and LD99.9968), divided by that of combined treatment, were between 1.47 and 2.47. In the confirmatory tests, no individuals recovered from a sum of 111,366 late-stage larvae treated under 1% O2 atmosphere for 14- or 15-d after 200 Gy irradiation, which resulted in validating the probit estimations and achieving an efficacy of 99.9973% mortality at 95% confidence level. Therefore, these treatment schedules are recommended to disinfest T. granarium infecting commodities for phytosanitary purposes under the warehouse, MA packaging, or in combination with international transportation by train or sea container.

Gnomoniopsis castaneae is the cause of the chestnut brown rot but has been also regarded as an important mortality factor for the chestnut gall wasp Dryocosmus kuriphilus. The question to whether G. castaneae could serve as a natural biocontrol agent against insect pests is investigated in the present study. We used three serious insect pests as experimental model insects: Plodia interpuctella and Trogoderma granarium, which are important pests of stored products, and Myzus persicae, a cosmopolitan, serious pest of annual and perennial crop plants. Although chemical pesticides represent effective control means, they are also related to several environmental and health risks. In search for alternative pest management methods, scientific interest has been focused, inter alia, on the use of entomopathogenic fungi. While Isaria&nbsp, fumosorosea has long been recognized as an effective control agent against several pests, G.castaneae has been very little studied. The present study examined whether and to what extent G. castaneae and I. fumosorosea exhibit insecticidal activity against fourth-instar larvae of P. interpunctella and T. granarium and adults of M. persicae. Mortality was examined in interrelation with dosage and time exposure intervals. Both fungi exhibited pesticidal action. However, G. castaneae induced noteworthy mortality only at very high doses. In general, we concluded that G. castaneae failed to cause high insect pathogenicity at normal doses and may not be an efficient biocontrol agent compared with other entomopathogens. On the other hand, our study reiterates the pathogenic potential of I. fumosorosea. More studies are needed to further our insight into the potential of EF species as a component of IPM.

The present study investigates the interaction between cannabidiol (CBD) oil and three biopesticides: Azatin and two baculovirus formulations (Madex and Helicovex), both separately and in combination, in order to investigate their interaction against adults of four major coleopteran stored-product pests: Sitophilus zeamais (Coleoptera: Curculionidae), Rhyzopertha dominica (Coleoptera: Bostrichidae), Prostephanus truncatus (Coleoptera: Bostrichidae) and Trogoderma granarium (Coleoptera: Dermestidae). CBD, which has been understudied for its insecticidal properties, was applied at three different doses (500, 1500 and 3000 ppm). The biopesticides were administered at 1500 ppm. Interactions in the combined treatments were mathematically estimated as not synergistic and mostly competitive except for the combined treatments of CBD (1500 and 3000 ppm) with Azatin (1500 ppm) which were marked by an additive interaction. In its individual application, CBD oil generated the highest insect mortality while its effect was clearly dose-dependent. The findings reveal a promising effect of CBD oil against these coleopterans which had not been previously tested together.

The use of chemical insecticides has had several side-effects, such as environmental contamination, foodborne residues, and human health threats. The utilization of plant-derived essential oils as efficient bio-rational agents has been acknowledged in pest management strategies. In the present study, the fumigant toxicity of essential oil isolated from Satureja intermedia was assessed against cosmopolitan stored-product insect pests: Trogoderma granarium Everts (khapra beetle), Rhyzopertha dominica (Fabricius) (lesser grain borer), Tribolium castaneum (Herbst) (red flour beetle), and Oryzaephilus surinamensis (L.) (saw-toothed grain beetle). The essential oil had significant fumigant toxicity against tested insects, which positively depended on essential oil concentrations and the exposure times. Comparative contact toxicity of S. intermedia essential oil was measured against Aphis nerii Boyer de Fonscolombe (oleander aphid) and its predator Coccinella septempunctata L. (seven-spot ladybird). Adult females of A. nerii were more susceptible to the contact toxicity than the C. septempunctata adults. The dominant compounds in the essential oil of S. intermedia were thymol (48.1%), carvacrol (11.8%), p-cymene (8.1%), and &gamma, terpinene (8.1%). The high fumigant toxicity against four major stored-product insect pests, the significant aphidicidal effect on A. nerii, and relative safety to the general predator C. septempunctata make terpene-rich S. intermedia essential oil a potential candidate for use as a plant-based alternative to the detrimental synthetic insecticides.

Trogoderma granarium Everts, the khapra beetle, is a serious stored product pest known to feed on &gt, 100 different products worldwide and is a major threat to global food security. Deltamethrin-treated storage bags are a resource that could be used to limit infestations during storage of grain in bags. We investigated the efficacy of deltamethrin-treated bags against T. granarium adults and larvae. Deltamethrin-treated and untreated packaging materials were affixed into the bottom of plastic Petri dishes (62 or 137 cm2) to create a bioassay arena. Adult T. granarium were exposed and observed to determine the time to knockdown and the subsequent mortality rate within 24 h. Adult T. granarium were knocked down in &lt, 60 min, and 100% of adults were knocked down or dead after 24 h. Trogoderma granarium larvae were exposed for 0.33, 1, 2, 3, or 4 d or continually exposed and monitored for larval death and adult emergence. Larvae exposed for 4 d had 50% mortality versus 97% if continually exposed. Utilizing this deltamethrin-treated packaging could cause disruptions in natural populations of T. granarium found in storage facilities, and the treated packaging is an effective tool that could be implemented into an integrated pest management program for bagged grain.

The khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae) is a dangerous insect of stored products that has currently expanded in Africa, Asia and Europe. Control of this species encounters difficulties when synthetic insecticides are applied either as surface treatments or as grain protectants. Therefore, new insecticidal formulations should be assessed as additional tools towards an effective management of T. granarium. In the current study, we tested the new insecticidal formulation Dobol, that contains the pyrethroid insecticide d-tetramethrin and the neonicotinoid insecticide acetamiprid, as treatments on concrete. Their direct and delayed mortality against adults and larvae of T. granarium were estimated under two label doses (min and max) and two temperature levels (30 and 35 °C) after 1, 2, 3, 4 and 7 d of exposure interval. Results revealed that Dobol caused direct mortality to T. granarium adults that ranged between 87.8 and 96.7%. Concerning larvae, direct mortality was generally much lower, being at most 84.4% at the max dose after 7 d of exposure. Temperature had significant impact on the direct mortality of T. granarium adults and larvae within the vast majority of the tested exposure intervals at both doses. However, when the surviving adults and larvae were transferred on untreated concrete surfaces, despite higher mortality at 35 than 30 °C, there was no significant impact of temperature on their mortalities within any exposure interval and dose. Our study revealed that Dobol is a promising insecticidal formulation that can be effectively used against adults and larvae of T. granarium on concrete surfaces.

The khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae), is one of the most destructive insect species of stored food worldwide and is subjected to strict phytosanitary legislations. In the present study, we evaluated the egg hatching and larval mortality of T. granarium on concrete surfaces treated with six insecticides (i.e., α-cypermethrin, chlorfenapyr, deltamethrin, pirimiphos-methyl, pyriproxyfen, and s-methoprene) that are registered in Greece for surface treatment and exhibit a broad spectrum of different modes of action. Furthermore, we investigated the influence of the presence of food on egg hatching and larval mortality. Egg hatchability on treated concrete was higher in tests with the presence of food for all tested insecticides, with the exception of s-methoprene. In contrast, larval mortality was lower in treatments where there was nourishment for all insecticides. No egg hatching was recorded on concrete treated with pirimiphos-methyl where there was no food, while with the addition of food, the egg hatching did not exceeded 26.7% after 6 days of exposure. The highest percentage of hatched eggs was recorded on concrete treated with chlorfenapyr (87.7% with food vs. 76.7% without food), followed by deltamethrin (76.7% with food vs. 63.3% without food), pyriproxyfen (50.0% with food vs. 42.2% without food), and α-cypermethrin (28.9% with food vs. 6.7% without food). In the case of s-methoprene, more eggs were hatched in the absence of food (91.1%) in contrast to in the presence of food (86.7%). Regarding mortality, all larvae were dead after 5 days of exposure on pirimiphos-methyl-treated concrete with food. Furthermore, larvae died faster in treatments without food. For α-cypermethrin, 100% mortality was recorded after 4 days of exposure, while with presence of food, all larvae died after 6 days. Chlorfenapyr caused complete mortality of larvae after 5 days of exposure on concrete without food and after 8 days with food. In the case of deltamethrin, 100% mortality was recorded after 7 days in the absence of food and 8 days in the presence of food. Regarding pyriproxyfen, complete mortality was not recorded when food was present, reaching 94.1% 14 days postexposure. However, after 12 days, all larvae died in treatments without food. Although egg hatching was higher in the case of s-methoprene on concrete without food, larval mortality was 100% after 8 days of exposure. Nevertheless, when there was food, 87.3% of the exposed larvae died after 13 days. Therefore, it becomes evident that sanitation of storage facilities before the application of contact insecticides is a key factor for the successful control of T. granarium in the egg stage.

Nano sciences or nanotechnology are the study of small things at nm scale, it is used across the all science fields, such as chemistry, Biology, physics, material sciences and engineering. Nano sciences is an emerging and vastly developed form that can encompasses the fundamental’s elements which can understand and advanced arising form of exploitation of materials, which have one dimension.Trogoderma Granariumwere collected from grain market, located in Faisalabad and population of insect was acclimatized to the laboratory. After extraction of plant materials (oils fromDatura stramoniumandSyzygium aromaticum) biosynthesis of nano-particles was done accordingly to standard procedure. Toxicity bioassays was done by three concentrations (5, 10 and 15 %) of the plant oils (for each of the simple plant oil) and 100, 200 and 300 ppm (for nano-particles) were used. Data regarding mortality was recorded after 24, 48, 72 and 96 hours of the treatment application. In case of plant oil, highest mortality (36.12%) was recorded byDatura stramoniumat 15% and after exposure period of 96 (hr.) whileDatura stramoniumsilver nanoparticle gave 41.40% at 300 ppm. Repellency bioassay was done by area preference method. Silver nanoparticles repellency highest range was 67.89% at 15% concentration ofDatura stramoniumand lowest was 28.31% at same concentration of theSyzygium aromaticum oils, used. Hence, plant based insecticides can be helpful for the management of stored commodities insect pests.

Khapra beetle, Trogoderma granarium Everts, is one of the world's most important pests of stored grain. Common in Africa and Asia, it is a quarantine insect for much of the rest of the world where methyl bromide has traditionally been used for its control. However, this ozone-depleting fumigant is now heavily restricted, and alternate methods of control are required. In a two-step process, we examined the use of high-temperature exposure as one such method of control. First, different life stages were held at 45°C for different periods to calculate LT50 (lethal time to 50% mortality) values. In descending order, the most heat-tolerant life stages at 45°C were diapausing larvae (LT50 = 41 - 122 h) > nondiapausing larvae (LT50 = 47 h) > adults (LT50 = 33 h) > pupae (LT50 = 25 h) > eggs (LT50 = 10 h). Second, diapausing larvae (the most heat-tolerant stage) were held at 45, 50, 55, and 60°C for different periods to calculate LT50, LT95, LT99, and probit 9 (99.9968% mortality) values. Estimated LT99 values for diapausing larvae were 288 h at 45°C, 6 h at 50°C, 1.1 h at 55°C, and 1 h at 60°C. Based on these results, an exposure of 2 h at 60°C is recommended to control T. granarium with high temperatures. To meet requirements for control of quarantine pests, exposure of between 2 and 12 h at 50-60°C is recommended to cause probit 9 mortality, but additional experiments are needed to get a better estimate of probit 9.

Insects damage grain during post-harvest storage. Grain loss during storage is a serious problem, especially in less-developed countries. In this study, a gaseous ClO2 treatment was applied to four different insect species known to damage stored grains: Sitophilus zeamais (Motschulsky), Trogoderma granarium (Everts), Callosobruchus chinensis (Linnaeus), and Tribolium castaneum (Herbst). Different insect species showed different sensitivities to the same ClO2 fumigation conditions. The 100 ppm treatment level with 24 h exposure is effective to controlling S. zeamais, T. granarium, and C. chinensis. However, to control T. castaneum, a higher concentration of the ClO2 gas or increased exposure time is needed. The 200 ppm treatment level with 48 h exposure is effective to controlling T. castaneum.

The khapra beetle, Trogoderma granarium Everts (Coloeptera: Dermestidae), is a globally serious pest of several agricultural stored-commodities. Among new methods that target to control this species is the insecticidal treatment of storage bags. In the present study, we tested the efficiency of alpha-cypermethrin (= α-cypermethrin), chlorfenapyr, deltamethrin and pirimiphos-methyl applied on woven polypropylene, biaxially oriented polypropylene and kraft paper storage bags against adults and larvae of T. granarium under three treatment scenarios: one surface of the storage bag was treated and individuals were exposed on treated or untreated surface or both surfaces were treated. We estimated the immediate mortality after 1, 3 and 5 days (d) of exposure. Then, we placed adults and larvae that were alive unto untreated surfaces of the same type of storage bags and evaluated the delayed mortality after 7 d of exposure. Regarding immediate mortality, the most effective insecticides were chlorfenapyr and pirimiphos-methyl against both life stages. All insecticidal combinations resulted in very high delayed mortality values that finally killed ≥91.1% of the initially exposed adult population of T. granarium while in several combinations all adults died due to the delayed mortality. The initial population of T. granarium larvae was further reduced through delayed mortality, but there were still alive individuals on the storage bags. In the majority of combinations with α-cypermethrin, deltamethrin and pirimiphos-methyl, there were no significant differences in the mortality levels of adults and larvae when they were exposed onto the treated surface of the storage bags having one or both surfaces treated. All insecticides performed equally on the three tested types of storage bags. The present study illustrates that the application of chlorfenapyr and pirimiphos-methyl on different types of storage bags could be considered as additional tools for the management and regulation of expansion of T. granarium.

The laboratory experiments were conducted to study the effect of Exposure Period and Concentration of Abrasive dust (Silica gel, Limestone and Gypsum) on Killing effect of larva and adults of Trogoderma granarium Everts. under laboratory conditions (25±5Cº and 65±5% R.H) in College of Agricultural and Forestry. Mosul University 2013. The results showed that the killing percent was clearly increased So as to increased of Concentration. The Silica gel Exhibit high effective in comparison with Limestone and Gypsum which revealed after two week of treatment had higher average values of larva and adults killing which reached 60, 70.33% respectively at Concentration 70g/kg. where as these values of treatment by Limestone and Gypsum were reached 33.33, 60% and 26.66, 40% respectively at the same Concentration. These results reflected to LC50 values of the abrasive dust which indicated that the adults had more susceptibility than larval stage in their responsable for used Dusts which LC50 values reached after two week of treatment 42.53, 58.88 and 101 ppm for Silica gel, Limestone and Gypsum respectively. These last results reflected too on the values of Relative efficiency and Relative susceptibility of two insect stage (larva, adults) and their higher values were recorded in Silica gel after two week of adults treatment which reached 422.34 for Relative efficiency 1 for Relative susceptibility compared with Gypsum which gave lower values on larval stage which reached 100 for Relative efficiency 0.226 for Relative susceptibility.

In recent years, the use of plant derivatives such as essential oils has been considered as a substitute for chemical pesticides in pest control. Essential oil of Cyperus rotundus L. rhizomes was extracted by hydrodistillation and its compounds were identified by GC/MS. Also, the contact toxicity and repellent activity of essential oil against adults Callosobruchus maculatus F., Oryzaephilus surinamensis L., and Trogoderma granarium Everts were evaluated in the laboratory (27 ± 2 °C, 65 ± 5% relative humidity, and dark conditions). The results showed that elemenone (13.59%), α-cyperone (13.14%), and caryophyllene oxide (13.03%) were the major constituents of essential oil. The values of LC50 for C. maculatus, O. surinamensis, and T. granarium in contact toxicity were 0.36, 0.51, and 0.2 μL/cm2, respectively. The repellency percentage of essential oil on O. surinamensis, T. granarium, and C. maculatus was 94%, 94%, and 80% after 2 h, and 90%, 92% and 70% after 4 h, respectively. According to these results, essential oil of C. rotundus can be used as a suitable substitute for chemical pesticides to protect the stored products against pests.

The effect of Hot air on the Killing a percentage of different stages of Red flour beetle Tribolium castaneum and The Khapra beetle Trogoderma granarium , have study: the larval stage of Khapra beetle is more resisting in expansion to Hot air in killing 50 a percentage having 104°C and in killing 95 % is in 110°C , in Red flour beetle the killed 50 % in all the stages of the same (82°C) but in the killing 95% the pupal stage is more resisting to arrive at 92°C and nearby in adult stage (90°C). Keywords: Hot Air, Control of Insects Stored Products, Local grain products, The Khapra Beetle, The Red Flour Beetle

The results indicated that the kinds of legume seeds and storage period affect to the activity of khapra beetle which represented in the population density of the insects and loss weight of infested seeds and growth rate of insect. The results indicated that the chick pea, Caw pea and green gram had more preferred for insect feeding than another legume seeds as lentil, broad bean, pea and bean, and had a high general mean for insect numbers was 245.67 insect for chick pea and followed caw pea seeds 188.00 insect and green gram seeds 140.89 insect. The general mean of insect numbers were increased with increasing storage period which were 26.05, 72.57 and 171.57 insect for storage period of 3, 6 and 9 moths respectively. According to other characteristics as loss weight, loss percentage of weight and growth rate were higher on the chick pea from another kinds. These characters that arranged between zero on the broad bean seeds and 15.67 gm., 62.68 % and 3.51 individual / month of the chick pea seeds.

The khapra beetle, Trogoderma granarium (Everts), is a highly destructive stored product insect that presents a significant threat to stored bagged grain. Hermetic packaging is designed to maintain the quality and safety of stored grain, while continually protecting the grain from insect infestations during storage. The objective of this research was to evaluate a prototype deltamethrin, all-in-one treated hermetic bag on contact efficacy, larval mobility, and the control of T. granarium in artificially infested wheat. The insecticidal activity of the deltamethrin-treated packaging was tested against larvae and adults of T. granarium through contact bioassays. There was a significant reduction in responsive adults after 5 day and >86% of larvae were unresponsive after 9 d of exposure on the treated bag. Trogoderma granarium movement toward a food bait was

In order to find new, less toxic and eco-friendly pest control agents, natural products are considered to be alternative options of potentially active compounds. In this context, the aim of the present study was the isolation and structural elucidation of the β-carboline and quinazoline alkaloids of Peganum harmala L. seeds. Silver nanoparticles (AgNPs) were prepared using alkaloids through a green synthesis procedure. Harmala alkaloids and their AgNPs showed considerable insecticidal and growth inhibitory activities against khapra beetle, Trogoderma granarium (Everts) (Coleoptera: Dermestidae). On a toxicity bioassay using treated filter papers, the total harmala alkaloids (THAs) were the most toxic followed by harmaline, harmine and harmalol, where LC50’s ranged between (30.6–61.7 µg/cm2) and (24.4–46.1 µg/cm2) 24 h post-treatment against larvae and adults, respectively. The two quinazolines, vasicine and vasicinone, showed moderate to weak activities. At 48 h post-exposure, efficacy of all alkaloids was increased. When tested as AgNPs (size 22.5–66.2 nm diameter), toxicity of alkaloids, especially the β-carbolines, was strongly increased, where LC50 values ranged between (4.7–11.4 µg/cm2) and (4.1–10.2 µg/cm2) 48 h post-treatment against larvae and adults, respectively. Feeding the 2nd instar larvae AgNPs-treated grains at sublethal concentrations led to significant drawbacks on the normal growth and development of the insect. These effects appeared as a high percentage of malformed larvae and pupae, a prolonged life span and a significant reduction in adult emergence. Results suggest the potential of using harmala alkaloids and their AgNPs as a natural approach for controlling T. granarium.

We evaluated the following six insecticides: cypermethrin, deltamethrin, pirimiphos-methyl, silicoSec, s-methoprene and spinosad, that are registered as grain protectants, against adults or larvae of the khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae) on wheat, barley, maize and rough rice. Three doses were tested: the half of the label dose, the label dose and the double label dose for each insecticide and mortality was assessed after 1, 3, 7 and 14 days (d) post exposure. For parental adults, progeny production was estimated after an additional period of 46 d of exposure. All tested insecticides were able to suppress T. granarium adults, even at the lowest dose. Pirimiphos-methyl and silicoSec were found to be most effective than the other insecticides, as these were the only ones that caused application resulted in 100% mortality at the 7-d exposure interval, at the half label or label dose. Conversely, the majority of the insecticides tested were found to be ineffective against T. granarium larvae. Pirimiphos-methyl was the only insecticide on which larval mortality reached 100% on all commodities tested and by far more effective than the other insecticides. For both adults and larvae, mortalities were generally higher on wheat and barley, than on rough rice and maize, for most of the combinations tested. Our findings indicate that the biological stage (i.e., adults or larvae) and the type of infected commodity should be seriously considered when insecticidal management strategies with cypermethrin, deltamethrin, pirimiphos-methyl, silicoSec, s-methoprene or spinosad are planned against T. granarium.

Trogoderma granarium, the Khapra beetle, is a major pest of cereal grains and nuts. In this research, the lethal and sublethal effects of Artemisia sieberi Besser essential oil (EO) was evaluated against 4th instar larvae of T. granarium under the laboratory conditions. Bioassays showed that the larvae were susceptible to both contact and fumigant toxicity. In contact and fumigant toxicity the calculated LD50 and LC50 were 44.3 μg/cm2 and 33.5 μL/L air, respectively. To assess the sublethal effects, 4th instar larvae were exposed to A. sieberi EO in contact (LD25 and LD50) and fumigant (LC25 and LC50) action. The larvae that exposed to LD50 of contact toxicity showed the lowest amylolytic activity (0.064 ± 0.007 mU/Individual) and intensity of bands. Control larvae had greater weight gain and consuming food compared to treated larvae. Furthermore, the highest and the lowest values of relative consumption rate (RCR) and relative growth rate (RGR) were observed on control (0.50 ± 0.02 and 0.084 ± 0.005 mg/mg/day) and LD50 of contact toxicity (0.26 ± 0.02 and 0.052 ± 0.002), respectively. Insects exposed to EO had smaller amounts of protein, glycogen and lipid content than control. Survival rate of EO-treated larvae after exposure to low temperature showed that the potency of contact toxicity was higher than fumigant toxicity for decrease of cold tolerance. Finally, exposure to EO in larval stage reduced the pupal and adults weight, longevity of female, fecundity and fertility. Our findings showed that A. sieberi EO has significant potential for use in controlling T. granarium, in both contact and fumigant applications.

Since time immemorial, the oleo-gum-resins of Ferula assa-foetida and F. gummosa are used in the traditional medical systems as well as in foodstuffs, perfumery and cosmetics. In the present study, we explored the insecticidal efficacy of the essential oils obtained from these oleo-gum-resins to widen their fields of industrial applications. The two essential oils were mainly composed of sulfides [sec-butyl (Z)-propenyl disulfide, sec-butyl (E)-propenyl disulfide, sec-butyl (Z)-propenyl trisulfide and sec-butyl (E)-propenyl trisulfide)] and monoterpenes (α-pinene, β-pinene and β-phellandrene), respectively, as determined by GC-MS analysis. The two essential oils were assayed for toxicity on a panel of insects, represented by species of public health relevance (Culex quinquefasciatus and Musca domestica), agricultural (Spodoptera littoralis) and stored-product pests (Prostephanus truncatus and Trogoderma granarium). The ecotoxicological effects of the essential oils were assessed on the aquatic microcrustacean Daphnia magna and the earthworm Eisenia fetida, as well as on human cells. Overall, the two essential oils were effective against important insect pests and vectors. On the other hand, they resulted cytotoxic to fibroblasts and non-target aquatic microcrustaceans. Thus, further insights are needed to determine the full spectrum of their eco-toxicological effects.

The study showed that the highest activation percentage of the insecticides (Spinosad, Emamectin and the mixture of the insecticides) were obtained when mixed with silica gel for the larvae grown on the corn (2.266, 1.255 and 1300 respectively), while the lowest activation percentage (Antagonism) was recorded for the mixture of each of the Spinosad and Emamectin separately with the gypsum of the larvae grown on the wheat giving 0.776 and 0.989, respectively. The highest of synergism percentage was for silica gel when mixed with each of Spinosad, Emamectin and the mixture of insecticide against the larvae which grown on corn reached 2.014, 1.178 and 1.256 respectively; the lowest of synergism percentage was for gypsum when mixed with the Spinosad and the insecticide mixture against larvae grown on the wheat, which reached 0.454 and 0.918 respectively, while the ratio was 0.841 for the Emamectin insecticide when mixed with the limestone against the larvae which grown on wheat. For the percentage of potentiation, the study showed that the treatment of larvae grown on wheat and corn which treated with a mixture (silica gel and Spinosad insecticide) gave the highest percentage of the potentiation of the pesticide reached 0.41 and 0.252 respectively, and the lowest potentiation percentage of larvae on wheat and maize was recorded for gypsum with the mixture of insecticides reaching 0.082 and 0.016 respectively.

Nanostructured silica can be used as a carrier of pesticides to enhance stability and controlled release of agrochemicals with an effective concentration on target pests. Silica nanoparticles (SNPs) were synthesized by sol–gel process and employed as a carrier of three different insecticides including deltamethrin, pyriproxyfen, and chlorpyrifos. The SNPs were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis and the insecticides-loaded in SNPs were characterized by transmission electron microscopy (TEM). The toxicity of insecticides alone and loaded in SNPs was evaluated against small and large larvae of Trogoderma granarium Everts on concrete surfaces. The immediate mortality was counted after 1, 3, and 7 d of exposure, and then surviving individuals were transferred to untreated surfaces for seven more days, with delayed mortality was recorded. Small larvae were more susceptible than large ones on all insecticide treatments. In addition, insecticides loaded in silica nanoparticles were more effective when compared with application of the insecticides alone. For immediate mortality, deltamethrin loaded in SNPs was the most efficient treatment causing 70.5% mortality on small and 55.5% mortality on large larvae after 7 d of exposure to the highest concentration. Pyriproxyfen loaded in SNPs caused low immediate mortality, but the mortality increased in delayed count indicated that the insecticide could control the larvae even after they have been removed from treated surfaces. It can be concluded that loading insecticides in SNPs could significantly increase their insecticidal efficiency, but this increase was compound-dependent.

New insecticide treatment options would be beneficial for control programs for Trogoderma granarium Everts, the khapra beetle, in the United States. Two insecticides were evaluated, the Polyzone&reg, formulation of deltamethrin and a formulation of the insect growth regulator methoprene combined with deltamethrin and the synergist piperonyl butoxide. In the test with Polyzone&reg, deltamethrin, concrete arenas were treated with a low and high rate, and held outside, inside a shed, or inside a lab. Compared to storage in the lab, residue degradation increased slightly in the shed, and then further outside, as evidenced by greater larval survival and adult emergence. Across all environmental treatments, the high rate was more effective than the lower rate. For the combination methoprene product, the effect of food contact with treated surfaces was examined. When treating arenas with food and transferring the food to clean dishes, there was no immediate effect on larval survival, but there was a reduction in survival and emergence to the adult stage after one month. For both tests, larvae apparently often went into diapause after they were introduced onto the treatment arenas. Both treatments could be utilized in management programs if T. granarium infestations are detected.

Simple Summary The resistance of coleopteran stored-product pests to phosphine fumigation is becoming a global phenomenon. However, there is limited literature available and a lack of knowledge on this issue in Pakistan. Thus, in the current study, we estimated the status of phosphine resistance among ten populations of Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae), Sitophilus granarius (L.) (Coleoptera: Curculionidae), Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) and Trogoderma granarium Everts (Coleoptera: Dermestidae), originated from different regions of Pakistan. Laboratory-susceptible populations of all insect species were also considered in the tests. Concentration–response bioassays were conducted for each insect species. All of the tested populations of each species were found to be resistant to phosphine. However, they varied with regard to their levels of resistance. Overall, R. dominica exhibited the highest resistance level, followed by T. castaneum, T. granarium and S. granarius. Although phosphine is effective against several stored-product pests, the development of resistance may lead to failures in its application in Pakistan. Abstract In Pakistan, the control of stored-product insect pests mainly relies on the use of phosphine gas along with other control tactics. The aim of this study was to determine the level of phosphine resistance among ten differently located populations of the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae), the granary weevil, Sitophilus granarius (L.) (Coleoptera: Curculionidae), the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) and the khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae). Laboratory-susceptible populations of all insect species were also considered in the experiments. Concentration–response bioassays were conducted for each species. All of the tested populations (10 out of 10) of each species were found to be resistant to phosphine, but varied in their level of resistance. Probit analysis estimated LC50 at 2.85, 1.90, 2.54 and 2.01 ppm for laboratory-susceptible populations of R. dominica, S. granarius, T. castaneum and T. granarium, respectively. Against R. dominica, the highest and lowest resistance levels were observed in the Rahim Yar Khan (LC50 at 360.90 ppm) and Rawalpindi (LC50 at 210.98 ppm) populations, respectively. These resistant populations were 126.67- and 74.02-fold more resistant than the laboratory population. The Multan and Lahore populations of S. granarius exhibited the maximum (LC50 at 122.81 ppm) and minimum (LC50 at 45.96 ppm) resistance levels, respectively, i.e., they were 64.63- and 24.18-fold more resistant than the laboratory population. The Layyah population of T. castaneum showed the maximum resistance level (LC50 at 305.89 ppm) while the lowest was observed in the Lahore population (LC50 at 186.52 ppm), corresponding to 120.42- and 73.43-fold more resistant than the laboratory population, respectively. Regarding T. granarium, the Layyah population showed the maximum resistance level (LC50 at 169.99 ppm) while the Lahore population showed the minimum resistance (LC50 at 74.50 ppm), i.e., they were 84.57- and 37.06-fold more resistant than the laboratory population, respectively. Overall, R. dominica presented the highest resistance level, followed by T. castaneum, T. granarium and S. granarius. The current study suggests that the application of phosphine may not be an adequate control strategy for the management of the above tested insect pests in Pakistan.