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Weevil infestations cause post-harvest losses and have become important constraints to storage entomology and food security in Nigeria. The present study is aimed at assessing the efficacy of Azadirachta indica-treated storage materials against Sitophilus zeamais and Sitophilus oryzae. Storage materials such as bagco bags, calico bags, and plastic containers were treated with different concentrations (0.5, 1.0, and 1.5mg/ml) of A. indica oil. Untreated storage materials served as the control. These treatments were replicated three times following a completely randomized design in the laboratory and monitored for 100 days. The results showed a significant decrease (p<0.05) in weight loss of infested maize and rice grains with different concentrations of the extract and with the different storage materials compared to the control. The highest weight loss among the treatment concentrations across all the storage materials treated with Azadirachta indica was recorded for rice grains stored in calico bags at 0.5mg/ml with mean value of 10.61±0.37 and7.12±1.41 for maize grains, while the least value of 1.14±0.09 was recorded for rice grains stored in plastic containers at 1.5mg/ml and 0.75±0.21 was recorded for maize grains stored in plastic containers at 1.5mg/ml. there was a significant increase (p<0.05) in mortality of S. zeamais and S. oryzae with increased concentrations of the extracts compared to the control. There was no significant increase in mortality of S. zeamais and S. oryzae compared with the storage materials. The highest mortality for S. oryzae 8.00±0.58 was seen in rice grains stored in plastic containers at 0.5mg/ml concentration and least mortality 4.00±0.58 was seen in those stored in bagco bag at 1.0mg/ml concentration. For S. zeamais, there was no significant increase on the mortality of S. oryzae between 0.5mg/ml and 1.0mg/ml concentrations in A. indica treated bagco bags and between 1.0mg/ml and 1.5mg/ml concentrations in A. indica treated plastic containers. S. oryzae in maize grains stored in plastic containers at 1.0mg/ml had the highest mortality 9.00±1.53 and the least mortality (3.00±0.00) was recorded for S. zeamais in maize grains stored in calico bag at 0.5mg/ml of A. indica treated materials. Results of the storage materials (Bagco bag, Calico bag, and Plastic container) treated with Azadirachta indica leaves extract showed significant decrease (p<0.05) in adult emergence of S. zeamais and S. oryzae in the different concentrations of extracts compared to the control. There was no significant decrease among the A. indica treated storage materials for S. zeamais and S. oryzae emergence. The highest S.oryzae emergence in A. indica treated bags was recorded for S. oryzae stored in Bagco bag at 1.0mg/ml with mean value of 177.67±9.21 and the least value of 107.33±3.76 was recorded for S. oryzae infesting rice grains stored in plastic containers at 1.5mg/ml. There was a significant decrease (p<0.05) in the number of holes bored by S. zeamais and S. oryzae in maize and rice grains treated with Azadirachta indica leaf extract compared to control across various concentrations and storage materials. The highest number of holes bored by S oryzae 390.00±28.22 in infested rice grains was recorded in Calico bag at 0.5mg/ml concentration and the least was recorded in plastic containers at 1.5mg/ml concentration (134.67±11.26). Similar trends were observed with Weevil perforative index and percentage damage. The study concludes that bagco bags treated with A. indica at 1.5mg/ml are more effective for protection of maize and rice grains in storage. [ABSTRACT FROM AUTHOR]

Phosphine is the most common fumigant used for stored product protection, and its use intensified with the global phasing out of methyl bromide due to its ozone depletion characteristics. These use patterns led to phosphine resistance, which was subjected to a globe-wide survey in the 1970's, but without a subsequent (global) update. Thus, the present work aimed to undertake a comprehensive review of the phosphine resistance literature published since the initial survey in 1975 until 2021. Next, meta-analyses were used to synthesize and quantify the resistance observed within the main insect pest species of stored products. Forty-six papers were recognized surveying 13 species of stored product insect species, encompassing 980 populations around the world; 72.96% of these populations exhibited phosphine resistance, and 10 out of the 13 species evaluated exhibited resistance in more than 60% of the populations tested. The most widespread problems were observed with the lesser grain borer (Rhyzopertha dominica), the rice weevil (Sitophilus oryzae), and the red flour beetle (Tribolium castaneum). The frequency of resistant individuals ranged from 12 to 48% for the populations. The levels of phosphine resistance were higher for the lesser grain borer (73-fold on average), followed by the red flour beetle (32-fold), and the maize weevil (28-fold). Furthermore, a considerable variability was observed within species and among localities. Therefore, phosphine resistance remains an ongoing problem and worldwide concern, with increasing levels and prevalence among key pest species of stored products, although reports and monitoring are largely circumscribed to four countries–Australia, Brazil, Greece, and the US. [ABSTRACT FROM AUTHOR]

The main objective was to search for a new chemical insecticide to control the stored grain insect pest Trogoderma granarium particularly when this pest developed resistance against the currently used insecticides. Clove oil has been traditionally considered as an effective pesticide. The present study aimed at determining the efficacy of clove oil against the 4th instar larvae of insecticide resistant populations of T. granarium collected from different regions of Punjab i.e., Layyah, Okara, Gujranwala and Lahore. The Layyah population of Khapra beetle was identified as the most susceptible population (LC50= 0.1%), and the Lahore population as the resistant one (LC50= 0.78%) after exposure to various oil concentrations. The energy reserves and degradation enzymes needed to breakdown these energy stores were the main focus of this study. The alterations in the levels of carbohydrates, proteins and lipids were remarkable after treatment with clove oil at LC20 and LC50 doses. In Layyah population, a considerable loss of total protein (28.93%), glucose (84.1%) and glycogen (55.71%) while an increase in trehalose (4.48%) and lipids (264.22%) were recorded after exposure to LC50 doses compared with unexposed group. In Lahore population, a reduction in lipid contents (45.97%), total protein (67.67%), glucose (50.45%), glycogen (34.36%) and trehalose (31.59%) were observed after treatment with LC50 doses in comparison with untreated group. In case of LC20 doses, a decline in all the tested energy stores of both populations were observed in comparison with their respective unexposed groups. The total activities of degradation enzymes i.e., trehalase, amylase and invertase in Layyah population decreased (56.25, 21.10 and 84.62%, respectively) and in Lahore population reduction in activities were 14.62, 87.45 and 75%, respectively after exposure to their respective LC20 doses as compared to their respective unexposed groups. The activities of all tested enzymes were decreased after exposure to LC50 doses except for invertase activity that increased after exposure to LC50 dose in Lahore population. The trends observed at LC20 doses were milder compared to that of LC50 dose. The clove oil can be used effectively against khapra beetle to control its damage. [ABSTRACT FROM AUTHOR]

Compounds with insecticidal properties from plant essential oils are an alternative to manage Sitophilus zeamais. However, these compounds can affect physiological processes such as seed germination and plant growth. The objective was to evaluate the toxicity of the Cymbopogon flexuosus essential oil by fumigation to S. zeamais and its phytotoxic to Zea mays. The mortality of S. zeamais was 100% with the doses of 20, 30, 40 and 50 µL of the C. flexuosus essential oil per 20 g of grains. The lethal dose (LD50) of this essential oil was 9.3 µL and its lethal time (LT50) greater with the 10 µL (18.8 h) and lowest with that of 50 µL (0.02 h), respectively. The doses of 10 and 20 µL of the C. flexuosus essential oil did not reduce the seed germination and growth of corn plants. The essential oil of C. flexuosus is an alternative for the control of S. zeamais. [ABSTRACT FROM AUTHOR]

Sitophilus oryzae or commonly known as Rice Weevil is a pest that infests stored rice grains. The feeding and movement of this pest within the grain produce sounds that are audible to a high-performance microphone sensor. This study presents a method for early detection of Rice Weevils based on the frequency of the sound they produce. Sound features were extracted using MFCC and utilized as input features to train a Convolutional Neural Network (CNN). The classifier was evaluated using 2800 acoustic samples containing positive and negative datasets. The experimental results show that the method can be an alternative approach for the early detection of the presence of rice weevils in stored rice grains. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Protection & Pathology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simple Summary: Hermetic (airtight) storage systems are used by smallholder farmers to mitigate storage losses caused by insects. These systems rely on insects to consume the residual oxygen within containers. However, prolonged exposure of infested grains to oxygen during hermetic storage can further exacerbate damage. While commercial oxygen scavengers can eliminate residual oxygen, they are costly, unavailable, and unsuitable for smallholder farmers in developing countries. We investigated the potential of germinating cowpea seeds (10, 20, and 30 seeds) as oxygen scavengers within 2 L airtight storage jars filled with cowpea grains. A set of jars was opened daily for 5 days to evaluate insect mortality, progeny, and grain quality. We observed a 100% insect mortality in 72 h when cowpea weevils were exposed to low oxygen levels from 20 and 30 germinating seeds. Infested grains exposed for 96 and 120 h to hypoxia from 30 and 20 germinating seeds, respectively, exhibited no post-treatment progeny development. For optimal results, a 2 L hermetic container filled with infested cowpeas containing 20 or 30 germinating cowpea seeds used as oxygen scavengers should be closed for 5 days. Millions of smallholder farmers use airtight (hermetic) storage to preserve stored commodities. However, relying on biological agents (i.e., insects) to deplete residual oxygen in airtight containers can occasionally extend the process, potentially resulting in grain damage or nutrient loss. Current oxygen scavengers used to remove this residual oxygen are unavailable and unsuitable on smallholder farms in developing countries. We evaluated the effectiveness of germinating seeds for oxygen depletion. Treatments comprised 10, 20, and 30 germinating cowpea seeds in 2 L jars filled with infested cowpea grains. Insect mortality and grain quality were assessed after 24, 48, 72, 96, and 120 h. Progeny development was monitored for 49 days post-treatment. The results showed that all germinating seeds depleted oxygen to 5% or below within 48 h. Complete adult mortality was achieved after 72 h for both 20 and 30 germinating seeds and 120 h for 10 germinating seeds. As germinating seeds increased, egg counts decreased. No adults emerged post-treatment after insects were exposed for 96 and 120 h to hypoxia from 30 and 20 germinating seeds, respectively. However, 120 h insect exposure to hypoxia from 10 germinating seeds had negligible progeny development. Moisture content increased slightly in grains exposed to 30 germinating seeds. Germinating seeds are as effective as controlled atmospheres in accelerating insect deaths, but further research is needed for field application and their effects on stored product quality. [ABSTRACT FROM AUTHOR]

The present study aimed to morphological identification of four species of pests that infect stored grains in Misan province in south Iraq during the period from January 2021 to December 2022. Samples of infecting grains included chickpeas, white and red beans, Indian and amber and American rice, bulgur, sesame, rice flour, flour, dried and canned dates, as well as samples of corn were collected from different regions, including the homes and local and central markets and general company for grain trade Misan branch. The results show that four species belonging to the order Coleoptera return to three families under the four genera. These species are Tribolium castanum Herbst,1797,Latheticcus oryzae Waterhouse, 1880, Trogoderma granarium Everts,1898, Oryzaephilus mercator Fauvel, 1889. [ABSTRACT FROM AUTHOR]

BACKGROUND: The application of allyl isothiocyanate (AITC) has been proposed as an alternative to control stored‐grain insects. However, AITC is a compound with a low diffusion coefficient, making its distribution throughout the grain mass difficult. Therefore, the objective of the present study was to evaluate the effectiveness of AITC applied in systems with or without recirculation for controlling Sitophilus zeamais (Mots. 1855) (Coleoptera: Curculionidae), Rhyzopertha dominica (Fabr.) (Coleoptera: Bostrichidae), and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) infesting a corn grain mass. The assays used a polyvinyl chloride (PVC) prototype, dimensioned 1.60 m in length, 0.30 m in diameter, and a static capacity of 60 kg of grains. AITC toxicity to insects was evaluated at the base, 0.5 m from the base, and top of the grain column (1.0 m). Different concentrations of AITC were tested for an exposure period of 48 h. RESULTS: In the system without AITC recirculation, insect mortality was verified only at the base of the grain column. However, insect mortality was considered uniform at the different positions of the column when the AITC recirculation system was adopted. In this system, there was also a marked reduction in the instantaneous population growth rate of S. zeamais, T. castaneum, and R. dominica, and a decrease in the dry matter loss of the grains, when the AITC concentrations were increased. CONCLUSION: AITC recirculation proved to be a viable strategy for protecting grains against the species S. zeamais, R. dominica, and T. castaneum. AITC fumigation ultimately did not cause changes in grain quality. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Copyright of Diversitas Journal is the property of Diversitas Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The common bean Phaseolus vulgaris in storage is frequently attacked by insect pests, which reduce the quality of the product. The use of phosphine fumigant insecticide to control stored grain insects has led to the selection of resistant populations, and alternatives are needed. In this context, the objective of this study was to assess the insecticidal effect of grapeseed oil (Vitis vinifera) and canola oil (Brassica napus) on Z. subfasciatus in stored bean. Contact tests were carried out to determine the lethal levels of LC50 and LC95 and their respective toxicity ratios, as well as to observe the number of eggs and insects after 12 and 30 days, respectively. For the repellency test, the number of insects attracted in the lethal concentrations LC50 and LC95 was observed, in addition to the reduction in the number of eggs and emergence. In the contact test, there was no difference in the toxicity of essential oils. Both oils were efficient in the reduction of the oviposition when compared to the control treatment, with canola oil presenting the highest reduction in the number of eggs with increasing concentrations. In the repellency test, the oils were repellent in the concentrations LC50 and LC95. The largest reduction in the number of eggs and insects was found in the grape seed oil. [ABSTRACT FROM AUTHOR]

In this paper, Sitophilus oryzae, Sitophilus zeamais, and Sitophilus granarius, three economically significant grain pests are thoroughly analyzed in terms of their morphological and molecular differences. The work provides critical insights into species identification, genetic differentiation, and adaptation by contrasting conventional morphological features and genetic approaches. The samples were collected from eight talukas of district Khairpur: Kingri, Kot Deji, Khairpur, Gamabat, Mirwah, Sobhodero, Nara, and Faizganj during the year 2018-2022. The samples were identified on the basis of morphology and extraction of DNA was done. The samples were sent for sequencing. The findings provide important evolutionary insights and aid in pest management. Additionally, the text describes the distinguishing physical characteristics of mature Sitophilus granarius, maize weevils, and rice weevils, emphasising size, colour, markings, and anatomical aspects. Understanding the differences among various weevil species is made easier by this information. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the chemical profile and acaricidal activity against the mite Suidasia pontifica of the essential oils from leaves of Piper marginatum Jacq and aerial parts (branches, leaves, and inflorescences) of Piper callosum Ruiz & Pav. From the aerial parts (branches, leaves and inflorescences) of P. callosum, three different essential oils were extracted with variations in the contents of their chemical constituents. The major compounds in the essential oil of P. marginatum were δ-3-carene and (E)-β-ocimene, while safrole was the predominant compound in the essential oils of P. callosum. Concentrations of 4 μL/L of the essential oil of P. marginatum and 2 μL/L of the essential oil of P. callosum killed all the mites tested after 72 h of exposure. The 50% lethal concentration ranged from 1.19 to 2.16 µl/L air for P. marginatum and from 1.22 to 3.44 µl/L air for P. callosum. [ABSTRACT FROM AUTHOR]

Discussion The tested aqueous extracts from plants I S. terebinthifolius i , I L. sericea i , I L. tomentosa i , I L. nervosa i , and I L. longifolia i , proved to be effective against I S. zeamais i in stored maize grains, with regard to their repellency. Keywords: bioinsecticide; aqueous extract; maize weevil; stored grains EN bioinsecticide aqueous extract maize weevil stored grains N.PAG N.PAG 11 09/27/22 20220901 NES 220901 1. This study aimed to determine the effects of botanical extracts of five plant species I Schinus terebinthifolius i , I Ludwigia sericea i , I L. tomentosa i , I L. nervosa i , and I L. longifolia i in reducing offspring emergence and repellency potential of adult insects. The plant species were deposited at the Herbarium of the Federal University of Grande Dourados-UFGD, with the following registration numbers: 6391 I L. tomentosa i , 6389 I L. longifolia i , 6388 I L. sericea i and 6390 I L. nervosa i , 6473 I S. terebinthifolius i . [Extracted from the article]

[Display omitted] • Schinus terebinthifolius essential oils showed the excellent yield. • The chemical composition of the essential oils of S. terebinthifolius was studied. • Sitophilus zeamais was susceptible to S. terebinthifolius essential oil. • S. terebinthifolius essential oil is more effective than synthetic insecticide against S. zeamais. Maize weevil, Sitophilus zeamais, is a major cause of damage to corn. The preventive control of this agricultural pest is performed with permethrin. However, due to the intensive use of insecticides, the population of S. zeamais has developed resistance to more than 10 synthetic insecticides, including the active ingredient permethrin. In the search for techniques aiming to reduction of the use of synthetic pesticides for the integrated management of S. zeamais , the present study was evaluate the effects of Schinus terebinthifolius essential oil – by fumigation, contact and ingestion methods – against populations of S. zeamais, both susceptible and resistant to the insecticide permethrin. Chemical profile identification showed α -pinene, β -myrcene, α -phellandrene, δ -3-carene and β -phellandrene were the major components in S. terebinthifolius essential oil. Permethrin susceptibility of the S. zeamais revealed four resistant populations (STP R , STP 1 , STP 2 and STP 3). But, in the Fumigant bioassay, STP R and STP 1 permethrin-resistant populations were susceptible to the essential oil. When the insects were put in direct contact with treated maize grains, only STP R permethrin-resistant population was susceptible this essential oil. Resistance ratio of the permethrin on S. zeamais populations revealed differences of permethrin susceptibility among the groups tested. S terebinthifolius essential oil exhibited high insecticidal activity, reducing the populations of S. zeamais through fumigation and contact/ingestion methods. The present findings suggest that use of permethrin can be substituted with the preparation of botanical insecticide with S. terebinthifolius essential oil. [ABSTRACT FROM AUTHOR]

Ozone (O3) is known as the powerful oxidant and has several beneficial applications, especially in biotechnology and agricultural industries. Ozone can be easily created on site with the use of electricity and air. Ozone is a safe antioxidant when used as a substitute to toxic chemical-based pesticides for the storage of grains. As the awareness and preference is augmenting among the people for consumption of organic foods; in this condition, O3 can play the major role as an effective and non-hazardous decontaminant. The O3 has half-life of 20–50 minutes because it rapidly decomposes to diatomic oxygen (O2), and leaving no harmful residue on the surface of grains. The, decayed O3 releases a single O2 atom that is highly reactive towards the cell membrane of bacteria and attacks the cellular components and disrupts normal cellular activity. It has been reported that, O3 at 350 to 600 ppm-h can show highly destructive effects on bacterial and fungal vegetative cells. On the other hand, it is also important to optimize the dose of O3 from species to species and genus of the different bacteria. Some strains of Escherichia coli are resistant to the lower dosage of O3. On overall analysis of scientific opinion and recent outcomes of the laboratory results, we strongly recommend that the use of O3 for the storage of grains should be further investigated and utilized at large scale. Preservation of grains by the use of O3 is also an ecofriendly and considered as a customer-caring method to reduce food pathogens from seed grains without applying any toxic chemicals. [ABSTRACT FROM AUTHOR]

Sitophilus zeamais (Coleoptera: Curculionidae) is a common pest in stored corn grains [Zea mays (Poaceae)]. Synthetic insecticides are effective to control S. zeamais; however, they can develop resistant insects and are toxic to humans and animals. Compounds with insecticidal potential from plants are alternatives for pest control. This study identified the chemical composition of Cymbopogon flexuosus (Poaceae) essential oil, its insecticidal and repellency activity against S. zeamais. The major chemical constituent found in the essential oil of C. flexuosus was citral (88%). The data showed that the essential oil of C. flexuosus and citral showed better insecticidal and repellent activity than the commercial insecticide Actellic used as positive control. The 100% mortality of S. zeamais was obtained at doses of 50 and 44 µL of essential oil and citral, respectively. The highest repellent activity was obtained with 40 and 50 µL of essential oil and 35.2 and 44 µL of citral, respectively, and the lowest with commercial insecticide Actellic. The lethal dose (LD50) was 18.10 and 18.95 µL for essential oil and citral, respectively. The lethal time was lower at doses of 44 and 50 µL essential oil and citral, respectively, and higher with the commercial insecticide. The insecticidal and repellent action of the essential C. flexuosus and its major compound confirms the potential of producing new biopesticide for the control of S. zeamais in Integrated Pest Management (IPM) programs in stored grains. [ABSTRACT FROM AUTHOR]

The need to eliminate chemical products and the search for ecological alternatives for the control of pests in stored grains based on vegetable powders, motivated the determination of the effect of milled powders of Piper auritum Kunth on Sitophilus oryzae L. for this P. auritum was prepared in different variants and drying temperatures, in two phenological phases: vegetative and reproduction-flowering, dried in the sun and shade, in three temperatures (35, 45 and 60 ° C). Six insects were placed in four replicates for each treatment, the deaths caused in the treatments were recorded and compared. In the vegetative phenological state, dried in the sun, the best efficiencies of P. auritum powder were obtained when the material was dried at 45 and 60 ° C, with 38 and 45 % mortality respectively, while in the shade, the dried material at 35 ° C he achieved 100 % mortality, this being the best treatment of all. The leaves of this plant (dried in the shade and milled) can be used for the control of S. oryzae in stored grains.

The side effects of pesticides and fumigants have led to the development of ecofriendly stored grains in insect management methods. Insect egg remover is one of the recent inventions to be used in the management of stored grain insects. The inner brushing arrangement in the device facilitates the crushing of the eggs, if any, in the grains. Investigations were made to determine the effectiveness of the insect egg remover for the management of stored grain insects. The number of times the grains passed in the device (one, two and three times) and the density of insects (10, 20 and 30) were the two factors of the experiment. After rotating the grains with eggs in the machine, they were incubated for 60 days for assessing progeny production and grains damage. The device proved effective in reducing the emergence of Rhyzopertha dominica (F) and Tribolium castaneum (Herbst) adults without the influence of the densities of insects artificially introduced in paddy and sorghum grains, respectively. The pattern of emerged adults was significantly less in three passes. In addition, the density of insects did not influence significantly the emergence of adults and grain damage. However, grains damage at 40 and 60 days of incubation was significantly affected by the number of passes in the device. The lowest damage was recorded in three passes and the highest damage was in untreated grains. Most farmers could benefit by using this mechanical device. The design of the device is such that it can facilitate in crushing eggs beside the rapid removal of adult insects from mild and severely infested grains and consequently prevent grains damage and eliminates the possibility of the pests developing resistance over time. However, the machine has the limitations of controlling only external feeding stored insects and this study recommends a cost-benefit analysis. [Fundam Appl Agric 2020; 5(3.000): 429-434]

There are several products that have been used for the control of Sitophilus oryzae L. However, the high resistance of the insect to various chemical products has motivated the search for new alternatives for its control, which led to evaluating the in vitro effect of the extracts from Pimenta dioica (L.) Merr, Callistemon citrinus (Curtis) Skeels and Syzygium malaccense (L.) Merr. & L.M. Perry on S. oryzae. The plant material was ground into particles smaller than 1 mm. The powder obtained was used to obtain extracts through three extraction methods (Soxhlet, assisted extraction with Ultrasound and Maceration), with n-hexane, ethyl acetate and methanol solvents. The yield of the extracts was determined and the biological action on S. oryzae was evaluated by means of the percentage of insect emergency mortality and weight loss. The extracts formed by Soxhlet and n-hexane were more effective in vitro on S. oryzae, but all showed high repellency.

Cowpea (Vigna unguiculata) is an important crop as a source of basic protein for populations in tropical countries, generating profit after the processing and storage of grains. However, the attack of pests such as cowpea weevil Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae) can limit the production of cowpea, with the insect causing qualitative and quantitative losses to the grains. Its control is commonly performed with fumigant phosphine, which due to its almost exclusive use, has selected resistant populations of insects, causing control failure. This way, the present research aimed to investigate the effects of essential oils of Betula lenta, Cinnamomum cassia, Citrus aurantium var. Amara and Acorus calamus in the treatment of cowpea grains [Vigna unguiculata (L.) Walp.] under storage conditions, for the management of Callosobruchus maculatus. The effects of essential oils were investigated through contact, fumigation, and repellency tests. The LC50 found in the test of contact was 0.61; 0.63; 0.64 and 22.98 μL/20 g of beans for the oils of A. calamus, B. lenta, C. cassia, and C. auratium var. Amara, respectively. Based on the data, the number of eggs and insects that emerged decreased as the concentration of essential oils increased. The LC50 values in the fumigation test were estimated at 5.16; 8.24; 25.84 and 35.31 μL/L of air for A oils. calamus, B. lenta, C. auratium var. Amara and C. cassia, respectively. In the repellency test, all oils acted like antagonists to C. maculatus biology, but the latter presented deterrence against the oviposition and the emergence of adults in most concentrations. These findings indicate that essential oils can be used to manage C. maculatus. [ABSTRACT FROM AUTHOR]

Oryzaephilus surinamensis (L.) and Sitophilus granarius (L.) are major pests of stored wheat, Triticum aestivum (Linn.) and cause huge economic loss to it. This study aimed to evaluate the toxic and repellent effects of Camelina sativa (L.) extract using green synthesis of silver nanoparticles against O. surinamensis and S. granarius. The bioassays were performed by applying three concentrations (5, 10 and 15%) of C. sativa extract and 200, 300 and 500 ppm in case of silver nanoparticles. Mortality was recorded at 24, 48 and 72 h while repellency was noted after 12, 24, and 36 h of the post-treatment. After 72 h of exposure, the highest concentration of C. sativa extract (15%) caused mortality of 43.1 and 35.2% to O. surinamensis and S. granarius, respectively. In repellency bioassays, the extract of C. sativa caused 37.7 and 30.2% repellency against O. surinamensis and S. granarius after exposure period of 36 h. While the highest mortality of 60.1% was observed against O. surinamensis at highest concentration (500 ppm) of the silver nanoparticles of C. sativa extract compared to S. granarius (46.2%) at same concentration after exposure period of 72 h. Highest repellency (42.7%) was observed against O. surinamensis at 500 ppm of the silver nanoparticles of C. sativa extract compared to S. granarius (36.2%) at same concentration after exposure to 36 h. The results revealed that green synthesized silver nanoparticles from C. sativa extract proved effective and can be used as eco-friendly management strategy of O. surinamensis and S. granarius. [ABSTRACT FROM AUTHOR]

Copyright of Arab Journal of Plant Protection is the property of Arab Society for Plant Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Plant Protection & Pathology is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Fumigant activities for three essential oils; Garlic oil (Allium sativum L); Chili pepper (Capsicum annuum L.) and Nigella (Nigella sativa L.) were assessed at different concentrations against the adult and 20-days old larval stages of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) in the laboratory. The accumulative mortality was observed at different exposure periods (3, 5 and 7 days). The residual effect of garlic oil that was the effective oil, on the treated wheat grains was evaluated with respect to histological changes in the liver, kidney, and stomach of rat fed on this treated wheat. The results showed that the mortality rates of treated stages increased with increasing the time of fumigation treatment. Moreover the highest essential oils toxicity at the Median lethal concentration (LC50) values for exposure periods (3, 5 and 7 days) to fumigation were (126, 53, and 47 mg/L air) for adult stage and were (79, 62, and 41 mg/L air) for larval stage, respectively in the case of Garlic oil treatment. While, the lowest essential oils effective was Nigella oil at the Median lethal concentration (LC50) values for exposure periods (3, 5 and 7 days) to fumigation were (3594, 629, and 335 mg/L air) for adult stage and were (1040, 416, and 227 mg/L air) for larval stage, respectively. The toxicity effect of various essential oils against adults and larvae of T. castaneum at the LC50at 7 days fumigation could be arranged in descending order as follows: Garlic oil, Chili pepper oil, and Nigella oil. The histological changes showed that the organs slightly affected at the fumigation for 3 days. It may be concluded that the garlic essential oil is the good effective fumigant to control T. castaneum in the stored products and it recommended that the fumigation period does not exceed 3 days. The garlic essential oil has the potential for applications in IPM programs for stored-grain pests because of its high volatility and fumigant activity and its safety.

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. [ABSTRACT FROM AUTHOR]

Insect pests not only damaged field crops during the growing season, but also injured stored grain and stored food commodities. The development of substitute treatments for pest control in food products is an increasing demand from the food industry, which should meet consumer demands for the minimum use or elimination of pesticides. Modified atmospheres with higher concentrations of atmospheric gases, especially carbon dioxide (CO2) provide a cost-effective method to kill pests of stored products. CO2 is one of the hastiest option for arthropods control among latest commercial treatments, proposing complete control within hours. In present study aimed to determine the efficacy of CO2 against different stages of Tribolium castaneum (Herbst) that affect stored-food products. Different levels of the carbon dioxide like 25, 30, 35, 40 and 45% were used to protect the different flours such as chickpea, wheat, peanuts, porridge, rice and maize from the larvae and adult of red flour beetle under laboratory conditions at 27 ± 2 °C with Light (L): Dark (D) 12: 12, and 65 ± 5% relative humidity. Results showed that mortality increased with the increase of concentration CO2 level. [ABSTRACT FROM AUTHOR]

Maize (Zeamays) and beans (Phaseolus species) are staple food, feed and sources of income for millions of people in developing countries and most especially for the people of the North West Region (NWR) of Cameroon. Production and storage of these grains is greatly hampered by inappropriate storage practices and pest infestation. This study determined the storage practices and insect pests associated with these grains in theNWR of Cameroon. A structured questionnaire designed to document the indigenous methods of storingmaize and beans against post-harvest insect pests with particular emphasis on plants and plant-derived materials used was administered to 29 farmers selected from Babungo, Kom and Oku villages in the NWR of Cameroon. Samples of maize and beans were also collected from the stores of respondents to collect and identify the insect species. The 29 respondents used more than one method to protect their grains against damage by insects in storage. The different methods implored were conventional methods, local plants and wood ash with independent counts (percentages) of 18 (62.1 %), 18 (62.1 %) and 7 (24.1 %), respectively. Sitophilus zeamais, Tribolium casterneum, T. confusum and Brachymeria spp. were recorded in maize while only Acanthoscelides obtectus was recorded in beans. There were no significant differences in the number of insects recorded across the study sites. Therefore, post-harvest insectpests are a common problem in the NWR of Cameroon. Farmers within this region also use different methods of post-harvest storage practices to combat these pests. Integrated methods of post-harvest management should receive high priority to prevent damage and losses incurred. Management practices should focus on further developing plants used in post-harvest storage. There is equally a strong need for training farmers on aspects of post-harvest storage practices and management in the NWR of Cameroon. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the efficacy of 10 isolates of entomopathogenic fungi as biocontrol agents against Rhyzopertha dominica. The isolates used were Beauveria bassiana (CEP 545, CEP 560, CEP 567), Metarhizium robertsii (CEP 381, CEP 401), M. anisopliae sensu lato (CEP 615, CEP 616, CEP 617) and Cordyceps (=Isaria) fumosorosea (CEP 303, CEP 309). Insects were sprayed with a conidial suspension of each fungus and incubated for up to 15 days under laboratory conditions. The percentage of mortality and the median survival time (MST) were estimated. Beauveria bassiana caused the highest mortality (47-65%) whereas the other fungal isolates caused a maximum of 21%. The isolates of B. bassiana CEP 545 and CEP 567 showed a MST of 8 and 9 days, respectively. Among all the tested isolates, B. bassiana CEP 545 resulted as the most efficient isolate as a biocontrol agent. The median lethal concentration (LC50) of this isolate was calculated with five concentrations within day 15 after treatment. The mortality increased with the highest concentrations and the LC50 was estimated in 9.54x109 conidia mL-1. This study demonstrated that some B. bassiana isolates, especially CEP 545, could be used as biocontrol agents against R. dominica. Highlights The B. bassiana native strains used in this research, especially CEP 545, showed high mortality rates and low LT50. All the fungal isolates evaluated decreased the survival rate of R. dominica. The percentage of mortality with B. bassiana CEP 545 increased as the concentration increased.

Essential oils, when used as bio-insecticides in the control of insect pests of stored grains have shown specificity and variation in the potentiality of their mode of action. In the present study, three essential oils extracted from three aromatic plants of different families, white wormwood (Artemisia herba alba, Asteraceae), oregano (Origanum vulgare, Lamiaceae) and rue (Ruta montana, Rutaceae), were evaluated for their repellent and fumigant toxic potential against the flour moth larvae, Ephestia kuehniella (Lepidoptera, Pyralidae), under laboratory conditions. The essential oils extraction was done by the hydrodistillation method. The repellent activity was carried out in Petri dishes using a filter paper treated with different oil dilutions (25, 75, 100, 120, 130, 150 µL/mL). The fumigant toxicity was determined on three concentrations (50, 130, 150 µL/L air). Two plants were shown to be repellent against the E. kuehniella larvae. Origanum oil was the most repellent with 67% of repellency rate followed by Artemisia oil (46%) at 120µL/mL after 2 hours of exposure. The oil of R. montana had an attractant activity against the larvae and was the most toxic with 56.7% of larval mortality in the first 24 hours. The median lethal concentrations (LC50) recorded were 11.6, 175.4 and 1100.0 µL/L air for the plant oils R. montana, O. vulgare and A. herba alba, respectively. R. montana and O. vulgare essential oil are shown to be efficient with high toxic and repellent properties against E. kuehniella larvae. Their specific potential could be integrated in the selection of the best bioinsecticides for the optimum protection of stored grain.

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae) is a primary insect pest of stored grains. The aim of this study was to evaluate the efficacy of 10 different isolates of entomopathogenic fungi as biocontrol agents against R. dominica. The chosen isolates were Beauveria bassiana CEP 545, CEP 560 and CEP 567, Metarhizium robertsii CEP 381 and CEP 401, M. anisopliae sensu lato CEP 615, CEP 616 and CEP 617 and Cordyceps (=Isaria) fumosorosea CEP 303 and CEP 309. Insects were sprayed with a conidial suspension of each fungus and incubated for 15 days under laboratory conditions. Insect mortality (expressed as percentage) and median survival times (MST) were estimated. Beauveria bassiana caused the highest mortality (47-65%), whereas the other fungal isolates caused a maximum mortality of 21%. The B. bassiana CEP 545 and CEP 567 isolates led to an MST of 8 and 9 days, respectively. Among all the isolates tested, B. bassiana CEP 545 was the most efficient as a biocontrol agent. The median lethal concentration (LC50) of this isolate was calculated with five concentrations on day 15 after the treatment. The insect mortality increased with the highest isolate concentrations and the LC50 was estimated in 9.54x109 conidia mL-1. This study confirmed that some B. bassiana isolates, especially CEP 545, could be used as biocontrol agents against R. dominica. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Entomología is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There are several products that have been used for the control of Sitophilus oryzae L. However, the high resistance of the insect to various chemical products has motivated the search for new alternatives for its control, which led to evaluating the in vitro effect of the extracts from Pimenta dioica (L.) Merr, Callistemon citrinus (Curtis) Skeels and Syzygium malaccense (L.) Merr. & L.M. Perry on S. oryzae. The plant material was ground into particles smaller than 1 mm. The powder obtained was used to obtain extracts through three extraction methods (Soxhlet, assisted extraction with Ultrasound and Maceration), with n-hexane, ethyl acetate and methanol solvents. The yield of the extracts was determined and the biological action on S. oryzae was evaluated by means of the percentage of insect emergency mortality and weight loss. The extracts formed by Soxhlet and n-hexane were more effective in vitro on S. oryzae, but all showed high repellency. [ABSTRACT FROM AUTHOR]

The efficacy of Diatomaceous Earth (Protect IT ®) was tested for the control of Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) in a metallic silo of Matanzas province, Cuba. A random design was arranged and three groups were evaluated: Protect IT (90% of diatomaceous earth), a positive control (Actellic CE 50) and an untreated control. The diatomaceous earth and Actellic were evaluated at 9.0 kg PC. ton - 1 and 12.0 ml. ton - 1, respectively. The dose of Diatomaceous Earth tested showed insecticide activity with 100% mortality percentage during the first 60 days, without statistical differences with the Actellic insecticide. After three months, the insect mortality was 60%, with statistical differences with the chemical insecticide. The results suggest the potentialities of Diatomaceous Earth (Protect IT ®) as an alternative for management of S. zeamais in metallic silos and for reducing the use of chemicals in corn grain storage. [ABSTRACT FROM AUTHOR]

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The objective of this work was to assess the fumigant and repellent effects of essential oils on adults of Callosobruchus maculatus and to identify the chemical composition of two of the tested essential oils. For the fumigation test, the oils of Schinus terebinthifolius, Piper aduncum, Syzygium aromaticum, Piper hispidinervum, Cymbopogon citratus, Cinnamomum zeylanicum, and the eugenol compound were tested at different concentrations on C. maculatus adults. For the repellency test, the oils of S. terebinthifolius, P. aduncum, P. hispidinervum, S. aromaticum, Jatropha curcas, and Ricinus communis were evaluated. In the fumigation test, it was observed that P. aduncum and eugenol showed the highest and lowest LC50s, of 169.50 and 0.28 μL L-1 air, respectively. In the repellency test, the oils of S. aromaticum and P. hispidinervum were repellent to C. maculatus. Gas chromatography coupled to mass spectrometry (GC-MS) analysis of these two oils identified 42 compounds, of which safrole was the main component of P. hispidinervum and eugenol of S. aromaticum. The essential oils of S. aromaticum, C. zeylanicum, and the eugenol compound are the most promising to control C. maculatus, via fumigation.

With the objective to determine the effect exerted by vegetable powders of Tithonia diversifolia (Hemsl) A. Gray, Moringa oleifera (Lam) y Piper auritum Kunth on Sitophilus oryzae L., this experiment was performed. In the execution, adult insects were taken to evaluate the increase of them. Petri dishes of 9 cm with 10 insects were used inside additionally 5 g of rice (Oryza sativa L.) and 0.4 g of powder was added botanical species (T. diversifolia, M. oleifera, P. auritum previously dried at 40 0C for 72 hours and finely ground). At 40 days the test mounted, the number of insects present per plate was counted, and after testing, Z Multiple Comparison was performed using the software Stadistix. The results allowed us to conclude that these plant species are a viable alternative for the control of S. oryzae.

Beetles of the species Sitophilus oryzae and S. zeamais are pests of great economic importance since they attack not only rice and maize but also several other cereals. In fact, these beetles are one of the most visible threats to sustainable food production. Current study estimated the genetic variability of S. oryzae in two samples, one from the State of Paraná (PR), Brazil, and another from the state of Rio Grande do Sul (RS), Brazil, and a sample of S. zeamais from the State of Santa Catarina (SC), Brazil. Isozyme electrophoresis in starch gel technique was employed to analyze eight enzyme systems (AAT, ACP, GDH, GPI, IDH, MDH, PGM and ME). Average heterozygosity rates were 0.0091, 0.0100 and 0.0000 and expected heterozygosity rates were 0.0419, 0.0452 and 0.0000 respectively for the samples of PR, SC and RS samples. The percentage of polymorphic loci was 30% in the PR sample, 0% in the RS sample and 30% in the SC sample. Genetic identity rates were I=0.9983 between samples from PR and RS; I = 0.6892 between PR and SC, and I = 0.6925 between SC and RS. Nei´s (1978) genetic distance rates were 0.0017, 0.3722 and 0.3675. Samples presented low genetic variability.

Mycotoxin contamination in grains is a significant concern due to its adverse effects on human and animal health. Understanding the levels and patterns of mycotoxin contamination in different regions and storage conditions is crucial for developing effective control strategies. This study aimed to assess mycotoxin levels in stored and recently harvested grains in three regions (Idah, Ajaka, and Ogbogbo) and investigate the implications for food safety. The study involved the analysis of mycotoxin levels in maize, rice, sorghum, and millet using appropriate mycotoxin extraction method based on the mycotoxins of interest and a suitable HPLC system. The findings revealed the presence of mycotoxins such as aflatoxins (1±0.2-5±0.4 µg kg -1 ), deoxynivalenol (520±0.8-700±1.2 µg kg -1 ), zearalenone (200±0.4-370±0.6 µg kg -1 ), ochratoxins (2±0.2-4±0.3 µg kg -1 ), and fumonisin (0±0.0-4±0.3 µg kg -1 ) in both recently harvested and stored grains. Patulin was absent in most of the samples. Variations in mycotoxin levels were observed among different grains and regions, highlighting the need for targeted interventions. The European Commission mycotoxin standards in grains for human consumption are: aflatoxins 4 µg kg -1 in maize, millet and sorghum while rice is 8 µg kg -1 , deoxynivalenal 1750 µg kg -1 , zearalenone 100 µg kg -1 , ochratoxin A 5 µg kg -1 for maize, rice and millet, then 10 µg kg -1 for sorghum. Fumonisin is 4000 µg kg -1 but no level for rice and patulin is 50 µg kg -1 for rice and none for the other grains. This study demonstrates the persistence of mycotoxin contamination in stored grains and the importance of considering specific crop types and geographical locations when addressing mycotoxin contamination. The findings underscore the significance of implementing effective control measures to mitigate mycotoxin contamination and enhance food safety. The study provides valuable insights into mycotoxin contamination and emphasizes the need for comprehensive risk assessment studies and appropriate regulatory measures., Competing Interests: The authors declare that there is no conflict of interest in this work., (© 2023 The Authors.)

Abstract: BACKGROUND: Brazil produces approximately 63 million tons of corn kernels annually, which is commonly contaminated with fungi and mycotoxins. The objective of this study was to evaluate the efficacy of gaseous allyl isothiocyanate (AITC) to inhibit the growth of Aspergillus parasiticus and Fusarium verticillioides, and mycotoxin production (aflatoxins B1, B2, G1 and G2, fumonisins B1 and B2) in corn during 180 days of storage. RESULTS: AITC at 50 µL L−1 resulted in a significant reduction of the fungal population (P < 0.05) after 180 days, decreasing 3.17 log(CFU g−1) and 3.9 log(CFU g−1) of A. parasiticus and F. verticillioides respectively in comparison with the control. In addition, 10 and 50 µL L−1 treatments prevented the production of fumonisin B1 for the whole period. Aflatoxins were not detected in either control or treated groups. Residual levels of AITC in corn treated with 10 µL L−1 and 50 µL L−1 were detected up to 14 days and 30 days respectively. CONCLUSION: Prophylactic treatment with AITC reduced the fungal population and inhibited fumonisin B1 production in stored corn, exhibiting great potential to be applied in corn silos to prevent fungi contamination and minimize mycotoxin levels. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]