Sitophilus Granarius Research Articles

Increasing the Oxygen Consumption in Hermetic Grain Storage Using Grain Weevils (Sitophilus granarius)

Loss of stored plant products due to insect infestation is a problem that is likely to increase with global warming. Improved storage under hermetic conditions in oxygen deficiency can prevent or control infestation and preserve product quality. Oxygen levels in hermetic storage decrease due to different factors, one of which is the oxygen consumption of the insects present. Experiments were carried out using varying numbers (25, 50, or 200) of all developmental stages of the grain weevil Sitophilus granarius L. (eggs, larvae, pupae, and adult beetles) caged and placed in sealed 30-L containers containing 22 kg of wheat for at least 21 weeks. Oxygen levels were measured at regular intervals. The oxygen consumption depended on the number of insects and went below the critical threshold of 3% for S. granarius survival in most of the trials. Some surviving beetles were observed at the end of the hermetic experiments and 12 weeks afterwards during control for progeny, when oxygen levels did not fall below the critical threshold or the low level could not be maintained for a sufficient time. Monitoring oxygen levels in hermetic storage is therefore essential to ensure safe storage over long periods.

Behavioural responses of Sitophilus granarius (L.) and Rhyzoperta dominica (F.) to odours of old and modern wheat genotypes

Sitophilus granarius (L.) and Rhyzopertha dominica (F.) are among the major stored-product pests worldwide. The identification of low or un-attractive wheat genotypes toward storage pests and their Volatile Organic Compounds (VOCs) profile is useful in breeding programs and in characterization of behaviourally active compounds suitable in developing semiochemical-based control means. Old wheat cultivars are genetic resources useful for breeding purposes. In this study, the VOC profiles of old genotypes, Senatore Cappelli, old Saragolla, Dauno III, and modern wheat varieties, Mec, Ofanto, Svevo, and Faridur, were characterized by headspace - solid phase microextraction (HD-SPME) and gaschromatography coupled with mass spectrometry (GC-MS) and their attractiveness towards S. granarius and R. dominica adults was evaluated in two-choice pitfall bioassays and Y-tube olfactometer, respectively. Sitophilus granarius adults were significantly attracted to odours of all varieties, with females being significantly more attracted by Faridur, Ofanto, Mec, and old Saragolla compared to Svevo. Rhyzopertha dominica males and females exhibited a significant olfactory preference for the odours of Faridur, Mec, and old Saragolla. The olfactory preferences of both species could be related to differences emerged in varietal VOC profiles. The most attractive variety for both species, Faridur, was rich in alcohols, alkanes, and terpenes. Old Saragolla, Ofanto, and Mec were rich in alcohols and organic acids. Dauno III was the richest variety in alcohols and lactones, and the poorest in aldehydes and terpenes compared to other varieties. Svevo showed the lowest amounts of alcohols and the highest value of aldehydes; Senatore Cappelli was rich in aldehydes, organic acids, and alkanes. The possible effects of the differences in VOC profiles on the olfactory preferences of insects are discussed. The study offers new knowledge for further investigation testing VOCs of the most and the lowest attractive varieties to identify effective attractants or strong repellents towards S. granarius and R. dominica.

Invasive Alien Plant Species Aqueous Extracts in a War Against the Granary Weevil (Sitophilus granarius [L.]) – are They Long-Term Effective or Can They Only Win the Battle of Cannae?

This study investigates the effectiveness of plant-based extracts in repelling the granary weevil (Sitophilus granarius), a common storage pest causing significant economic losses. The selected plant species (Canadian goldenrod, giant goldenrod, indigo bush, staghorn sumac, and tree of heaven), were examined for their repellent effects on weevils in grain samples. Surprisingly, the short-term repellent effects observed after 24 hours diminished after 3 days, suggesting potential challenges for practical applications, especially in long-term grain storage. Temperature emerged as a significant environmental factor, influencing weevil behavior. Lower temperatures created an illusion of increased effectiveness, while higher temperatures accelerated weevil reproduction. Commercial product NeemAzal, despite its reputation for effectiveness, proved the least potent among all treatments, raising questions about its applicability in such cases. Progeny emergence tests indicated no significant differences between treatments, emphasizing the ineffectiveness of the extracts in sustaining long-term repellent effects. The study concludes that while plant-based extracts may offer short-term victories in pest control, their long-term efficacy remains uncertain. The complex interplay of factors, including temperature and humidity, highlights the challenges in developing sustainable and practical solutions for grain storage pest control, necessitating careful consideration by real-world users.

Histological Studies on Liver, Lung and Kidney of Albino Mice Fed on Wheat Infested with Granary Weevil, Sitophilus Granarius

Histological Studies on Liver, Lung and Kidney of Albino Mice Fed on Wheat Infested with Granary Weevil, Sitophilus Granarius

Bioefficacy of Mucana pruriens extracts against Rice weevil, Sitophilus oryzae (Coleoptera: Curculionidae)

In the agricultural sector, the rice weevil, Sitophilous oryzae L. is one of the most damaging pests, causing significant economic losses worldwide. It is an internal feeder of grains. The female rice weevil causes damage to the grain by creating a hole in it and laying her eggs inside. The main purpose of our study was to investigate the biological effect of an aqueous extract of Mucana prurienson rice weevil under laboratory conditions. To assess the biological activities, data like number of the days to adult emergence, total adult emergence, percent infestation, weight loss, adult longevity, and adult sex ratio were recorded. The findings showed that, in the case of a 100 mg/ml plant extract, the maximum number of days needed for the adult emergence of rice was 66 and 72 days for wheat weevil, and the minimum number of days required was 20 and 25 in case control of both rice and wheat grains. When rice grains were treated with 0 mg/ml aqueous extracts, the maximum number of adult emergences observed was 72 on rice grains, while 66.00 occurred on wheat grains. The highest percentage of infestation (40.00%) was found in rice grains, while the highest percentage (39.78%) was found in wheat grains treated with 0 mg/ml aqueous extracts. The lowest weight loss (7.99%) was observed in rice grains and the highest weight loss (16.66%) in wheat grains treated with 100 mg/ml extracts; on the other hand, the lowest weight loss (13.33%) was observed in rice grains and the highest in wheat grains treated with 0 mg/ml aqueous extracts. When weevils were raised on untreated rice and wheat grains, the longest recorded adult lifespan was achieved overall. For rice weevil control that is safer, plant aqueous extracts with concentrations of 100 mg/ml and 75 mg/ml ought to be utilized. The present studies were carried out to examine the environmentally friendly aqueous extracts of Mucana pruriens and their pesticidal efficacy in controlling rice weevil. The study anticipates that Mucana pruriens extracts will exhibit significant insecticidal properties, potentially providing a natural alternative to synthetic insecticides. This study contributes to sustainable pest management strategies for stored grains.

Odourless vegetable oils as insect pest repellents for short-term protection of various food packaging materials

The repellent activity of two odourless vegetable oils (sweet almond—SAO and soybean—SO) applied on filter paper and four types of food packaging materials (polyethylene film, plastic gunnysacks, cardboard, and wood) was tested against three species of stored product pests (Sitophilus granarius, Tribolium castaneum, and Oryzaephilus surinamensis). The repellence of three doses was evaluated after 24 h, and after 7, 14, 21, and 28 days. Both oils exhibited a repellent effect when applied to filter paper, but this effect decreased with time and concentration. The most susceptible species was T. castaneum. The maximum repellence was 84% and 76% for SO and SAO, respectively. On packaging materials, the repellent effect diminished after a certain period of time, ranging from 7 to 28 days. Subsequently, the oils even became attractive. Generally, the repellent effects of both SO and SAO were higher on cardboard and wood slab than on polyethylene film and plastic gunnysacks. As such, in the case of SO, the repellence against T. castaneum was 88% 24 h after application on cardboard, whilst 68% on plastic bag. This work demonstrated the repellent potential of vegetable oils in the short term for the protection of packaged food against stored product pests.

Population growth of different stored product species on wheat, barley, and tritordeum

Stored product species can be developed in a variety of stored product grains. In this study, were compare three different grains for their suitability for population growth of primary and secondary stored product insects. In the first series, we evaluated the population growth and damage of Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae), Sitophilus granarius (L.) (Coleoptera: Curculionidae) and Sitophilus oryzae (L.) (Coleoptera: Curculionidae) on whole wheat, barley and tritordeum kernels after 65 days. In the second series, three different percentages of whole and cracked kernels were tested: 100% cracked kernels, 100% whole kernels and 50% cracked +50% whole kernels, for Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae) and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). The results showed that tritordeum was suitable for the population growth of all species tested. In most of the cases, R. dominica showed higher frass production but S. granarius showed a higher number of damaged kernels. Cracked kernels were preferred by secondary pests than whole kernels and wheat showed the highest progeny production than tritordeum and barley. Overall, commodity, and grain type and percentage of cracked kernels can affect the population growth of stored product insect species. Results of this study showed that stored product insect species can develop in tritordeum and thus should be taken into consideration for further results as may be damaged during storage.

Biological Study on the Granary Weevil, Sitophilus granarius (L.) on Stored Wheat During the Different Seasons with Special Reference to Its Host Preference

Biological Study on the Granary Weevil, Sitophilus granarius (L.) on Stored Wheat During the Different Seasons with Special Reference to Its Host Preference

Environmental impact assessment of dicationic ionic liquids with ammonium-phosphonium cations and amino acid anions

Progress in the development of biodegradable or biobased ionic liquids (ILs) has led to the design of green compounds for several applications. Herein, four biocompatible dicationic ionic liquids (DILs) with ammonium-phosphonium cations and amino acid anions were synthesized and investigated their environmental impact. The structures of the DILs were confirmed by spectral analyses (1H, 13C and 31P NMR). Furthermore, physicochemical properties such as density, viscosity and refractive index were determined. Water content, bromide content and solubility were thereafter determined as the parameters needed for further studies. Subsequently, their antifeedant activity towards economically important pests of grain in storage warehouses: the granary weevil, the confused flour beetle, and the khapra beetle was examined, showing the dependence on structure. Moreover, selected DILs were investigated for toxicity towards white mustard, Daphnia magna, and Artemia franciscana to specify the environmental impact. These studies were complemented by understand the biodegradation of DILs by bacterial communities derived from soil at the agricultural land. The result was DILs with limited environmental footprints that have great potential for further application studies.

Surface application of diatomaceous earth, SilicoSec® are effective on Sitophilus granarius and Rhyzopertha dominica, but less against Tribolium confusum

Diatomaceous earth (DE) has a promising potential in the control of stored-product pests. Most of the studies on the insecticidal potential of DE products are based on their persistent effects or the mortality they lead to via mixing with the grain. However, the knowledge on the performance of DEs on a particular surface is limited. In the current study, the insecticidal efficacy of a DE product, SilicoSec® was investigated against adults of Sitophilus granarius, Rhyzopertha dominica, and Tribolium confusum by surface application at 2.5, 5.0, 10.0, and 20.0 g/m2 on a concrete surface that is commonly used in storage structures. In S. granarius experiment, the highest immediate mortalities (89.2-99.2%) were obtained by the 5-day exposure even at the lowest rate (2.5 g/m2), while the highest delayed mortalities were 92.5% and 85% at rates of 2.5 and 20 g/m2, respectively by the 3-day exposure. In R. dominica experiment, the highest immediate mortalities (92.5-98.3%) were obtained by the 3-day exposure even at the lowest rate, while the highest delayed mortalities were 90.1 and 98.3% at rates of 10 and 20 g/m2, respectively, by the 1-day exposure. In T. confusum experiment, the highest immediate mortalities (83.3-91.0%) were obtained by the 7-day exposure at 10 or 20 g/m2, while the highest delayed mortalities were obtained by the 7-day exposure, and were 90.0 and 95.9% at rates of 10 and 20 g/m2, respectively. In conclusion, the insecticidal effect of surface application of SilicoSec® was high, moderate, and low against S. granarius, R. dominica, and T. confusum, respectively at concrete surfaces. A rate of 2.5 g/m2 of SilicoSec® provided an efficient control for S. granarius and R. dominica by 3- and 5-day exposures, respectively, while comparable mortality was obtained at a higher rate (10 or 20 g/m2) and exposure time (7-day) for T. confusum.

Investigation of the control of Sitophilus granarius in stored grain using vacuum packaging and the creation of an anaerobic atmospheric environment

The efficacy of vacuum and oxygen absorption-based treatments for controlling Sitophilus granarius L. damage in wheat grains was compared under laboratory conditions. The efficacy of the treatments was evaluated at different temperature ranges (−5, 26, 42 °C) and exposure times (0.5, 1, 3, 6, 24, 48, 72 h). Treatment-survived adult progeny were measured on day 45. Our studies demonstrated that the efficacy of the controlled atmosphere methods (CAs) we tested varied significantly as a function of time. While the mortality curve induced by the different temperature-controlled low-pressure vacuum packaging treatments is logarithmic, the mortality trend induced by the absorber's low oxygen levels follows an exponential slope. The hypoxia induced by low oxygen levels has a much longer duration of action. We have shown that vacuum packaging at lower and higher pessimum temperature ranges other than the thermal optimum of the insect induced significant mortality of S. granarius. The method was particularly effective when vacuum-packed items were kept at a higher pessimum temperature range. Our results confirm that vacuum packaging based on atmospheric modification, especially at elevated temperatures, can be a sustainable solution for pest control of small volume, valuable seed samples.

A new economical route for the grapefruit peel essential oil: Nanoemulsion form and insecticidal activity

The essential oil (EO) extraction is one of the ways to utilize of grapefruit (Citrus paradisi L.) peel waste. However, the low stability and penetration problems of EO limit their use. These limitations can be overcome by nanoemulsions. Therefore, this study aimed to form and characterize of the grapefruit peel essential oil nanoemulsion (EON) and investigate its insecticidal properties against Sitophilus granarius (Linnaeus, 1875) and Tribolium castaneum (Herbst, 1797) for an alternative bio-economic way. The grapefruit peel EON (4:3:3:90 w/w, EO:Tween 80:Ethanol:water) was formed by using the grapefruit peel EO with major chemical components such as d-limonene (85.70 %), myrcene (3.57 %), α-pinene (1.17 %). The grapefruit peel EON was characterized by TEM (50–120 nm), Zeta sizer (the mean droplet particle size: 109.3 nm, ζ-potential value:-20.6 mV, polydispersity index:0.265) and FT-IR analysis. 500 ppm of the grapefruit peel EON caused 50 % and 20 % mortality in S. granarius and T. castaneum after 7 days, respectively. 1000 ppm of the grapefruit peel EON caused 85 % and 50 % mortality in S. granarius and T. castaneum after 7 days, respectively. Based on the findings, the grapefruit peel EON may be considered having the potential to integrate management strategies for these pests and open a new bio-economic way.

Insecticidal activity of Mentha piperita L. (Lamiaceae) essential oil against two important stored product pests and its effect on wheat germination

This study aimed to evaluate the contact activity of the essential oil derived from Mentha piperita L. (Lamiaceae) against two significant stored product pests, namely Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae) and Sitophilus granarius (Linnaeus, 1758) (Coleoptera: Dryophthoridae), in a controlled laboratory setting. For this purpose, concentrations of 0.05, 0.1, and 0.15 µl/insect of plant essential oil were applied to stored product pests using a microapplicator. Dead insects were counted at 24, 48, 72, and 96 hours after application. As a result of the study, the essential oil demonstrated contact activity at varying rates depending on the applied pest and dose. After 24 hours, the 0.15 µl/insect application dose was the most effective against T. castaneum, resulting in a 23.6% mortality rate; after 96 hours, this rate increased to 33.4%. The essential oil exhibited greater contact activity on S. granarius, resulting in a 93.4% mortality rate after 24 hours when administered at a concentration of 0.15 µl/insect. At the end of 96 hours, the mortality rate at the same dose was found for S. granarius to be 98.2%. In addition, the effect of essential oil on the germination power of wheat grain was examined at doses of 2, 5, 10 and 20 μl/Petri under laboratory conditions. 73.8% of the seeds germinated at the maximum dose of 20 µl/Petri, while 99.4% germinated at the minimum dose of 2 µl/Petri. The research findings indicate that the essential oil of M. piperita possesses the capacity to be employed for the management of S. granarius.

Cymbopogon winterianus (Java Citronella Plant): A Multi-Faceted Approach for Food Preservation, Insecticidal Effects, and Bread Application.

Certain plants like Rosemarinus officinalis, Lavandula angustifolia and Origanum vulgare have been used in the food industry for centuries. Cymbopogon winterianus (Java Citronella plant) is one of the most significant plants. The objective of this study is to screen for secondary metabolites by phytochemical screening, evaluate the antioxidant contents of extracts and investigate the use of the Java Citronella plant in food preservation and as an insecticide. Java Citronella powder was added to bread and evaluated for its moisture content, and a visual and sensory analysis was performed. Sitophilus granarius (L.) weevils were exposed to Java Citronella essential oil (JCEO). The phytochemical screening revealed that the extracts were abundant in secondary metabolites. The JCEO had a yield of 0.75%. The aqueous extract had a higher total phenolic content of 49.043 ± 0.217 mg GAE/g than the ethanolic extract, which was 24.478 ± 1.956 mg GAE/g. The aqueous extract had a total flavonoids content 27,725.25 ± 54.96 µg RE/g higher than the ethanolic extract, with 24,263 ± 74 µg RE/g. The ethanolic extract had stronger antioxidant activity, with anIC50 = 196.116 μg/mL higher than the aqueous extract at 420 μg/mL. The 2% Java Citronella powder in the bread was preferred by consumers, and had a shelf life of 6 days. JCEO killed all the weevils with a high dose of 10% after 48 h. The Java Citronella showed insecticidal and food preservative activity. The results should help in future research to enhance the applications of Java Citronella in various domains, from food technology to insecticides.

Evaluation of Some Grain Protectants and Ozone Gas against Sitophilus Granarius L. In Stored Wheat Grain

Evaluation of Some Grain Protectants and Ozone Gas against Sitophilus Granarius L. In Stored Wheat Grain

Ruta chalepensis L. (Rutaceae) uçucu yağının beş coleopteran depo ürün zararlısına karşı fumigant ve kontak toksisitesi ile kolinesterazlar üzerine etkileri

The essential oil composition of aerial parts of Ruta chalepensis L. was analyzed with GC-MS. Seventy-nine compounds were detected representing 85.93 ± 1.08% (n = 3) of the essential oil. The major components of the essential oil were 2-undecanone 21.52 ± 0.21%, 2-nonanone 18.31 ± 0.27%, and 2-nonyl acetate 13.22%. The highest insecticidal contact toxicity of the oil was observed against Rhyzopertha dominica F. with 0.018 μl/insect LD50 and 0.039 μl/insect LD90 after 24h. Essential oil also produced considerably low 0.50 and 0.59 μl/insect LD50 values after 24h against Sitophilus oryzae L. and Sitophilus granarius L. respectively. The lowest contact toxicity was observed against Tribolium castaneum Herbst. and Tribolium confusum Jacquelin du Val. 0.138 and 0.078 μl/insect LD50 after 24h respectively. The highest fumigant toxicity was observed against S. granarius for the application concentration of 10 μl, 10% oil/acetone (v:v) in a 10 ml chamber which afforded 100.00 ± 0.00% mortality after 48h. The essential oil also produced high fumigant toxicity against S. oryzae, T. castaneum and R. dominica which were 95.47 ± 3.41%, 93.30 ± 5.54%, and 85.47 ± 3.41% mortality at 20 μl application concentration of the oil solution after 48h. The R. chalepensis essential oil produced low acetylcholinesterase enzyme 5.29 ± 1.20% (n=3) inhibition and mediocre butyrylcholinesterase enzyme inhibition 42.6 ± 0.71% (n=3). According to the insecticidal activity assays performed, the essential oil R. chalepensis seems to be a promising source that could yield natural compounds that could be employed in stored product pest management.

Insecticidal Effect of Thymus citriodorus (Pers.) Schreb (Lamiaceae) Essential Oil on Sitophilus granarius (Linnaeus, 1758) (Coleoptera: Dryophthoridae) and Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae)

In the current study, the essential oil of Thymus citriodorus (Pers.) Schreb (Lamiaceae) was evaluated for its ability to control adults of two significant pests of stored products, Sitophilus granarius (Linnaeus, 1758) (Coleoptera: Dryophthoridae) and Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae), under laboratory conditions. Using a microapplicator, test insects were exposed to 0.025, 0.05, 0.1 and 0.15 µl/insect concentrations of plant essential oil in order to assess contact toxicity. At 24, 48, 72, and 96 hours following applications, deaths were noted. The experiment revealed that, depending on the insects and dosages, the essential oil showed varying degrees of contact activity. The essential oil of T. citriodorus generally had low effect on adult T. castaneum, with the greatest effect was 15.32% at 0.15 µl/insect dose after 96 hours. Adults of S. granarius showed greater sensitivity to the essential oil of T. citriodorus. After 48 hours, doses of 0.1 and 0.15 µl/insect concentrations of the essential oil resulted in over 95% of S. granarius adult mortality. The findings of the study indicate that T. citriodorus essential oil has the potential to be used in the control of S. granarius.

Eucalyptus and spearmint oils inhibit the biological activity of lesser grain borer and red flour beetles

The objective of this investigation was to assess the insecticidal efficacy of essential oils derived from eucalyptus (Eucalyptus camaldulensis) and spearmint (Mentha spicata) against two species of stored-product insects. The process of Clevenger-type water distillation was employed to extract essential oils from two distinct plant species. Subsequently, the insecticidal properties of these oils were evaluated against specimens of the American wheat weevil (Rhyzopertha dominica) and the red flour beetle (Tribolium castaneum), belonging to the Coleoptera: Bostrichidae and Tenebrionidae families, respectively. Eucalyptus oil exhibited the highest level of inhibition of insects’ reproduction. Still, when tested on adults of both types of insects, eucalyptus and spearmint oils were more effective than the control treatment. A complete inhibition of egg-laying activity (100%) was achieved using a 7% concentration of eucalyptus oil. The trials were done within controlled laboratory settings, with a notable absence of tests conducted under authentic operational conditions. Researchers who want to learn more about using essential oils as insecticides in the future should focus on making pesticide formulations that work well in a wide range of production settings.

Determining the Toxicity of Thyme Essential Oils against Sitophilus granarius L. and Sitophilus oryzae L. (Coleoptera: Curculionidae) Adults

The present study aimed to determine the effects of three different doses of three thyme essential oils on Sitophilus oryzae (L.) and Sitophilus granarius (L.) (Coleoptera: Curculionidae). The present study was conducted under controlled laboratory conditions (25°C temperature and 65% relative humidity) in 2020. Various thyme varieties (Origanum majorona (L.), Origanum saccatum P.H. Davis, Thymbra spicata var spicata L. ( Lamiaceae)), cultivated in Diyarbakır province ecological conditions were employed in the study. After the 4th day of the experiment, the highest mortality rates (100%) were observed with the highest doses of T. spicata var spicata and O. majarona on S. granarius adults, while the mortality rate was 73.75% with O. saccatum. The LC90 values for T. spicata var. spicata, O. majarona, and O. saccatum were 0.9, 0.1, and 1.3 µl/ml respectively. After the 4th day, 100% S. oryzae adult mortality was observed with higher doses of O. majarona (0.5%; 1% v/v), while 1% (v/v) T. spicata var spicata dose led to a 72.50%, and 1% (v/v) O. saccatum oil dose led to 46.25% mortality.

Competition between Two Species of the Genus Sitophilus (Coleoptera: Curculionidae) on Wheat and Barley

Species can coexist and infest stored products at different population densities. We evaluated the population growth of Sitophilus oryzae (L.) and Sitophilus granarius (L.) (Coleoptera: Curculionidae) on wheat and barley in laboratory conditions. Ten adults of each species were placed in vials containing wheat or barley alone or in combination, and the number of adults was counted after 65 and 120 days. These tests were performed at 25 and 30 °C. Moreover, the number of damaged grain kernels and the weight of frass produced were also recorded. In general, the simultaneous presence of both species had a negative effect on the population growth of either S. oryzae or S. granarius. Nevertheless, no significant differences were noted regarding the number of damaged kernels and the weight of frass in most of the combinations tested. Moreover, the temperature seems to have a negative effect if both species were combined, especially at 30 °C. Our results showed that there was competition in the progeny production capacity when both species were together, but this competition was temperature and commodity-mediated.