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Background: This overview explores the use of entomopathogenic nematodes (EPNs), fungi (EPFs), bacteria (EPBs), and viruses (EPVs) as biological control strategies against the red palm weevil (RPW) (Rhynchophorus ferrugineus), a significant pest of date palms in Saudi Arabia. Laboratory and field studies have evaluated the efficacy of these pathogens, which employ different infection mechanisms to manage RPW populations. The review aims to provide insights into the pathogenicity and application methods of these microbial agents, supporting the development of sustainable integrated pest management strategies for date palm cultivation. Results: The results indicate that entomopathogenic nematodes (EPNs), fungi (EPFs), bacteria (EPBs), and viruses (EPVs) are effective microbial agents for controlling the red palm weevil (RPW), a significant pest of date palms in Saudi Arabia. Laboratory and field studies have demonstrated their efficacy, utilizing different infection mechanisms to manage RPW populations at various life stages. However, limitations exist, including a lack of comprehensive research on certain microbial pathogens and the need for further studies to optimize application methods and environmental adaptability. These gaps highlight the importance of this review in synthesizing findings and providing a solid foundation for future research on sustainable integrated pest management strategies for RPW control. Conclusion: This overview underscores the potential of entomopathogenic microorganisms as effective biocontrol agents against the red palm weevil, emphasizing their role in sustainable pest management strategies. Continued research is essential to address existing gaps and optimize the application of these microbial agents in date palm cultivation. [ABSTRACT FROM AUTHOR]

Simple Summary: Rhynchophorus ferrugineus is a noxious curculionid species found in date palm and coconut plantations worldwide. Its overall cryptic nature inhibits early detection of infestation symptoms and allows for its rapid expansion. Control methods in plantations usually include single-mode broad-spectrum chemical insecticides to both prevent and mitigate infestations. However, ecological concerns about hazards of both ecosystem and public health, call for safer and more sustainable solutions, including attractants, agronomic approaches, natural enemies and entomopathogenic organisms. This review highlights the published information on the biological traits, host plant spectrum, and management options such as biotechnic and biological control methods like the application of microbial organisms. Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae), the red palm weevil (RPW), is a concealed voracious pest of different ornamental and economically important palm species, particularly the date palm. It can cause huge losses in ornamental and commercial palm plantations. RPW has spread rapidly from its original distribution in Southeast Asia to date palm-growing countries worldwide. It is now established in more than 50% of date palm-growing countries and 15% of the coconut-growing countries globally. To prevent further expansion of this pest, many countries have implemented strict legislative and quarantine measures surrounding the export of the palms plant genetic resources from RPW-infested countries. This review focuses on the general biology (life history, development), host range, geographical distribution, and management on the basis of biotechnic methods, farming practices, natural enemies, and important microbial control agents. [ABSTRACT FROM AUTHOR]

Simple Summary: Insects have specific immune priming to pathogenic microorganisms, such as Bacillus thuringiensis (Bt). However, there may be a trade-off between immunity and development during immune priming and its molecular signaling pathways have not yet been reported. Our study found that Bt priming regulated the development and immune trade-offs in Rhynchophorus ferrugineus by activating the immune gene Spatzle, thereby inhibiting SHADOW transcription and 20E synthesis. Our results contribute to a deeper understanding of the trade-off during immune priming of insects and provide new targets for biological controls of Rhynchophorus ferrugineus. The red palm weevil (RPW) is an invasive pest that causes devastating damage to a variety of palm plants, which exhibit specific immune priming to Bacillus thuringiensis (Bt). However, immune priming in RPW may incur a high fitness cost, and its molecular signaling pathways have not yet been reported. Here, we investigated the effect of Bt priming on RPW development and subsequently analyzed the hormonal and immune-related molecular pathways influencing the fitness cost induced by Bt priming. Bt priming delayed the body weight gain of fifth-instar larvae and prolonged their developmental duration. Bt priming significantly reduced the 20-hydroxyecdysone (20E) content in RPW hemolymph, and the expression levels of the 20E biosynthesis-related genes SHADOW and SHADE were significantly downregulated. Furthermore, we analyzed Toll pathway genes influencing Bt priming and found that only Spätzle (SPZ) transcription was significantly activated under Bt priming. After silencing SPZ expression, the negative effects of Bt priming on development, SHADOW expression, and 20E synthesis were eliminated, thereby suggesting that SPZ is a key molecular signal mediating developmental and immune trade-offs induced by Bt priming. Our results elucidate the molecular cascade pathway of immune priming and provide new targets for improving the efficiency of RPW biological controls. [ABSTRACT FROM AUTHOR]

This review is aimed at exploring the use of remote sensing technology with a focus on Unmanned Aerial Vehicles (UAVs) in monitoring and management of palm pests and diseases with a special focus on date palms. It highlights the most common sensor types, ranging from passive sensors such as RGB, multispectral, hyperspectral, and thermal as well as active sensors such as light detection and ranging (LiDAR), expounding on their unique functions and gains as far as the detection of pest infestation and disease symptoms is concerned. Indices derived from UAV multispectral and hyperspectral sensors are used to assess their usefulness in vegetation health monitoring and plant physiological changes. Other UAVs are equipped with thermal sensors to identify water stress and temperature anomalies associated with the presence of pests and diseases. Furthermore, the review discusses how LiDAR technology can be used to capture detailed 3D canopy structures as well as volume changes that may occur during the progressing stages of a date palm infection. Besides, the paper examines how machine learning algorithms have been incorporated into remote sensing technologies to ensure high accuracy levels in detecting diseases or pests. This paper aims to present a comprehensive outline for future research focusing on modern methodologies, technological improvements, and direction for the efficient application of UAV-based remote sensing in managing palm tree pests and diseases. [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.)

The red palm weevil (Rhynchophorus ferrugineus) is a highly destructive pest, causing severe damage to palm trees and significantly reducing their productivity. This paper aims to develop and analyze a mathematical model that captures the interactions between palm trees, Rhynchophorus ferrugineus, and entomopathogenic nematodes as a means of integrated control. We identify the equilibrium points of the system and perform a stability analysis to assess the system's behavior. Additionally, we design a linear quadratic regulator (LQR) to limit the spread of the red palm weevil within a locally linearized framework. The feedback control law, which is both straightforward and immediately implementable, is employed to avoid the need for complex cost calculations, thus simplifying the solution to the optimal control problem. Numerical simulations demonstrate that the proposed control strategy is effective in reducing the number of infected palm trees. The results indicate that increasing the population of entomopathogenic nematodes can significantly decrease the red palm weevil population, offering a promising approach to mitigating this pest's impact. [ABSTRACT FROM AUTHOR]

This study deals with the field application of lure traps for trapping of the adult red palm weevil (Rhynchophorus ferrugineus) at the date palm orchard of Sindh, Pakistan. The pheromone traps, were installed at the date palm orchard under the field conditions such as aggregation pheromone dosage, food material (molasses), ester (isoamyl acetate) and trap density. During the field trials, it was observed that the 3 mg/trap dose of aggregation pheromone along with the 500 g of molasses and 4 mg/trap of ester trapped maximum female adult insects. The 10 traps/ha was the optimized trap density. Moreover, the higher number of insects were trapped in March and the minimum catches were observed in the month of November, December, January and February. The total male and female adult weevils captured were (N=18 females 60% and N=12 males 40%) and the sex ratio was 2:3 male and female, respectively. [ABSTRACT FROM AUTHOR]

Red palm weevil (RPW) (Rhynchophorus ferrugineus) threatens most palm species worldwide. This study investigated the molecular responses of coconut (Cocos nucifera) leaves to RPW infestation through metabolomics and transcriptomics analysis. An RPW insect attack model was developed by placing different RPW larval densitiesin coconut plants and measuring the relative chlorophyll content of different leaf positions and physiological indicators of dysfunction after RPW infestation. The metabolomic changes were detected in the leaves of 10, 20, 30, 40, and 50 days after infestation (DAI) using GC-MS. Certain metabolites (glycine, D-pinitol, lauric acid, allylmalonic acid, D-glucaro-1, 4-lactone, protocatechuic acid, alpha, and alpha-trehalose) were found to be possible indicators for distinct stages of infestation using metabolomics analysis. The influence on ABC transporters, glutathione, galactose, and glycolipid metabolism was emphasized by pathway analysis. Differentially expressed genes (DEGs) were identified at 5, 10, 15, and 20 DAI through transcriptomics analysis of infested coconut leaves, with altered expression levels under RPW infestation. The KEGG pathway and GO analysis revealed enrichment in pathways related to metabolism, stress response, and plant–pathogen interactions, shedding light on the intricate mechanisms underlying coconut–RPW interactions. The identified genes may serve as potential markers for tracking RPW infestation progression and could inform strategies for pest control and management. [ABSTRACT FROM AUTHOR]

The red palm weevil (RPW), scientifically known as Rhynchophorus ferrugineus, poses a significant threat to various palm species, leading to substantial economic losses in affected countries. The success of R. ferrugineus infestations can be attributed to numerous factors, such as its discreet behaviour, highly chitinized mouthpart, and prolific reproduction. Efforts to control R. ferrugineus, including insecticides, have encountered challenges such as resistance development and environmental harm. Consequently, there is a vital requirement for environmentally friendly chemicals that specifically target R. ferrugineus, with the chemosensory system being a potential focal point. The chemosensory system of the insect, which is crucial to its interaction with its plant host, could provide an effective strategy for preventing infestations. However, current knowledge about R. ferrugineus chemosensory system, including its anatomy, physiology, and relevant receptors or proteins, remains limited. This review aims to compile existing information on the chemosensory system to guide future research initiatives. It highlights the lack of omics-derived data on the chemosensory system of R. ferrugineus. It emphasises the need for a deeper understanding of the structural and functional aspects of related proteins. The review underscores the necessity for comprehensive, multidisciplinary approaches, such as systems biology and computational methods, to unravel the complexities of R. ferrugineus chemosensory system. The review discusses recent findings and seeks to inform and inspire future research endeavours to prevent R. ferrugineus infestations through targeted strategies. In conclusion, omics data available on the chemosensory system of R. ferrugineus is plentiful. This information is a valuable resource that enables analyses to identify potential targets for enhanced pest management strategies. [ABSTRACT FROM AUTHOR]

Despite the severe relevance of Red Palm Weevil (RPW) Rhynchophorus ferrugineus as an insect pest, the strategies applied to control it were poorly sufficient. Hence, this study tested the effects of using food bait pheromone traps (FBPTs) to control RPW. In this context, the experimental design used three types of baits (banana, date, and mixture) represented as (300 g banana, 300 g date, and 300 g mixture "150 g banana & 150 g date); three colors (red; white and black) and their combinations. They were checked once every two weeks to collect the samples caught and evaluate the efficiency roles in controlling RPW regarding the dynamic fluctuation and seasonal activity of RPW during 2021 at Taif governorate, Saudi Arabia. Data illuminated that the black color was significantly (P < 0.05) higher in attracting RPW, followed by red, and the lowest value was recorded at white color with the same bait. Notably, black traps containing date had the highest significance (P < 0.05), and the lowest was recorded in white traps containing bananas in attracting RPW. According to the presence of RPW throughout the year, the highest and lowest population densities were recorded during April and September, respectively. Remarkably, results exhibited a negative significant correlation between RPW mean population density and temperature, but there was a positive correlation between seasonal abundance and relative humidity. Interestingly, this study remarkably the pheromone traps with baits partially with data showed a significant effect in controlling RPW. Data showed that the dynamic fluctuation relationship of the red palm weevil and its relationship to some environmental factors have been changed during different seasons and peaks of weevil activity during spring and lowest during autumn. [ABSTRACT FROM AUTHOR]

The red palm weevil is a notorious insect pest of the palm family around the palm-growing regions of the world. This study investigated the biological effects of six commercially important date palm varieties viz. Dahki, Muzaft, Aseel, Gulistan, Begum Jungi and Fasley on red palm weevil. The newly emerged larvae were cultured on soft portion of the stem of selected varieties in plastic boxes at controlled conditions between 27 ± 2 °C and 65 ± 2% R.H. in incubators. The observations were documented on the number of eggs laid, fecundity, larval and pupal developmental periods, adult life span and sex ratio of red palm weevil. The Dhakki variety was found as the most susceptible having maximum number of eggs hatching (9.5) and weight losses (8.90 g) whereas; Fasley variety was found least susceptible having least egg hatching percentage (8.47) and weight losses (2.94). The maximum total larval developmental duration of 87.2 days was recorded on the variety Fasley which decreased to 64.8 days when red palm weevils were cultured on Dhakki variety. The maximum survival was recorded on variety Dhakki while the minimum survival was recorded on the variety Fasley. The maximum adult longevity (110 days) of female weevils was recorded on variety Dhakki while minimum adult longevity of 50.27 days was recorded on variety Fasley. Our results indicated that varieties significantly influence the development of red palm weevil and can be used as a viable tool for the management of red palm weevil. [ABSTRACT FROM AUTHOR]

Simple Summary: This study examined the behavior of red palm weevils in the United Arab Emirates to develop better and more environmentally friendly trapping methods. The study was conducted in three phases from June to December 2023 in Ras Al Khaimah and Abu Dhabi. Chemical attractants, such as pheromones, ethyl acetate, and food baits, like dates and coconut water, were tested. The weevils were most active between 3:00 and 6:00 a.m., with 85.72% being captured during this period. Adding pheromones to the food bait increased the capture rate by 6.95 times, and while adding food bait and ethyl acetate, and pheromones improved the capture rate by 3.14 times compared to using pheromones alone. The newly synthesized pheromone captured 2.69 times more weevils than the commercially available pheromone. This study examined red palm weevil ecology in the United Arab Emirates to develop effective food baits, pheromone, and eco-friendly trapping methods. Three phases of investigation were conducted (from June to December 2023) on date palm farms in Ras Al Khaimah and Abu Dhabi. The first two phases, each 15 days long, were conducted in Ras Al Khaimah, whereas the third phase, 18 days long, was conducted in Abu Dhabi. Chemical attractants, such as existing pheromones and ethyl acetate, a newly synthesized ferruginol pheromone, and food baits, such as original dates, date paste, coconut water, and date palm syrup, were used to attract the weevils. Multi-funnel traps containing various attractant mixes were tested. The main activity of the red palm weevils was observed from 3:00 to 6:00 a.m., with 85.72 ± 3.39% being captured during this period, coinciding with cooler temperatures. When pheromones were added to the food bait, the capture rate increased by 6.95 ± 1.81 times. Combining food bait, ethyl acetate, and pheromones improved the capture rates by 3.14 ± 0.69 times compared to pheromones alone. The newly synthesized pheromone achieved capture rates 2.69 ± 0.07 times higher than those of the commercially available pheromone, confirming its suitability as a red palm weevil attractant. [ABSTRACT FROM AUTHOR]

The red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier) (Coleoptera: Dryophthoridae), is a destructive and voracious pest of palm species worldwide. Due to environmental and regulatory concerns, ecologically safe alternatives to synthetic chemical insecticides are needed to manage this cryptic insect species. Entomopathogenic fungi have the potential to manage this pest. The scope of management and effectiveness can be improved by direct control or horizontal transmission of entomopathogenic fungal isolates. We tested in the laboratory the virulence and pathogenicity of fifteen different entomopathogenic fungal isolates belonging to the following species: Beauveria bassiana, Metarhizium anisopliae, Beauveria brongniartii and Purpureocillium lilacinum. All fungal isolates were found virulent against larvae (14.9 ± 1.06 to 81.5 ± 1.48% mortality) and adults (5.6 ± 1.12 to 51.7 ± 1.51% mortality) at 12 d post-treatment. From a screening bioassay, five M. anisopliae (WG-08, WG-09) and B. bassiana (WG-23, WG-24, WG-25) isolates were tested for their concentration response mortality against larvae and adults after 7, 14 and 21 days (d) of treatment. Mortality was found positively correlated with concentration and time. At 21 d of treatment, WG-23 and WG-25 1 × 108 conidia/mL resulted in 100% mortality against larvae while only WG-25 1 × 109 conidia/mL caused 100% mortality of adults. Along with mortality, all the potential isolates have strong ovicidal effects that reduced 81.49% at 1 × 108 conidia/mL. The horizontal transmission bioassay indicated that the infected adults transmitted the disease to healthy individuals. Horizontal transmission of fungi from infected to non-infected adults not only caused significant mortality but also had a serious sublethal impact on insect development and fitness including reduced number of eggs/d fecundity, egg viability and neonate survival. Isolate WG-25 reduced oviposition (0.5 eggs/d), fecundity (11.7 eggs/female), egg viability (11.6%) along with larval survival 25.9% when infected male mated with normal female. In semi-field trials, all fungal isolates reduced survival of larvae found inside the palms and ultimately reduced infestations over a period of two months. The results of this study indicate that entomopathogenic fungi should be further tested for sustainable and efficient control of RPW in date palm production systems. [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.)

Aggregation pheromone (ferrolure+) has the potential for sueeessful deteetion, monitoring and management of Red palm weevil (RPW), Rhynchophorusferrugenius. Therefore, studies were undertaken to evaluate the effeetiveness of aggregation pheromone (ferrolure+) along with synthetie inseetieides i.e., Karate 0.25 EC (Lambda-eyhlothrin), Coragen 20SC (Chlorantranliprole), Curaeron 50 EC (profenophos), Steward 150EC (indoxaearb) andTalstar 10EC (bifenthrin) for the management of RPW. Control treatments with and without ferrolure+ were also maintained. Four traps per aere were applied in eaeh study arranged in a randomized eomplete bloek design. Weekly observations were taken till the effeetiveness of ferrolure+. Results eonfirmed that addition of synthetie inseetieides showed a negative impaet on the mean eapture of RPW exeept for indoxaearb (7.59±0.89 weevils per trap) that attraet signifieantly same but eomparatively less RPW attraeted towards only ferrolure+ pheromone traps (8.74±0.96 weevils per trap). Overall RPW eaptured in remaining treatments i.e., ehlorantranliprole, lambda-eyhlothrin, profenophos and bifenthrin were 4.56+0.65 weevils per trap; (5.22+0.69) weevils per trap; 5.63+0.71 weevils per trap and 5.48+0.89 weevils per trap, respeetively. A gradual rise was reeorded in mean eapture of RPW in all treatments till week five after installation and then deelined rapidly upto week eight. More than double number of females were eaptured in traps with maximum male to female ratio (1:2.26) eaptured in lambda-eyhlothrin treatment. Therefore, it is suggested that ferrolure+ traps should be ineluded in the integrated management programs of RPW and indoxaearb pestieide, if required, may be added in trap to get maximum killing of weevils, partieularly females that will also help reduee future population growth. [ABSTRACT FROM AUTHOR]

Copyright of African Journal of Biological Sciences is the property of African Journal of Biological Sciences 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: Public demand for the reduction, or even total elimination, of chemical residues in agricultural products, coupled with increased concerns about the detrimental environmental effects of chemical or synthetic pesticides, facilitated the need to develop alternative pest control means in agriculture. Microbial control agents (MCAs) are considered an attractive alternative to chemical insecticides due to ecological safety with no residues, wide host range, and competitive prices. Here, we evaluated several insect-killing fungi as a preventative control measure against the destructive palm pest, the red palm weevil (RPW), in lab experiments and in the greenhouse. The fungi were applied on healthy Washingtonia palms as a protective mean prior to being challenged with the RPW. The results demonstrated that treated palms were significantly less colonized by the RPW, and the fungi prevented the establishment of this severe pest. This study is the first stage in our bigger research endeavor for protecting date palm plantations with EPF. The red palm weevil (RPW) Rhynchophorus ferrugineus is a highly destructive invasive pest for palms whose management is mainly by application of synthetic pesticides. As a key pest of date palm plantations, it is necessary to integrate environmentally safe measures for its management. Entomopathogenic fungi (EPF) have been primarily studied as a preventative control measure due to the horizontal transfer of conidia within the RPW population. We previously demonstrated the horizontal transmission of fungal conidia from an egg-laying surface to the female weevil and then to the eggs and larvae. Based on that strategy, this study aimed to evaluate the virulence of commercial EPF products and laboratory EPF preparations to RPW females and their progeny, and their ability to protect palms against infestation. As such, it serves as a screening platform for field experiments. Mortality rates of females and eggs depended on the applied treatment formulation and fungal strain. Velifer®, a Beauveria bassiana product, and Metarhizium brunneum (Mb7) resulted in 60–88% female mortality. Mb7—as a conidial suspension or powder—resulted in 18–21% egg-hatching rates, approximately 3 times less than in the non-treated control. Treating palms with Mb7 suspension or dry formulation significantly inhibits infestation signs and results in protection. These results lay the foundation for investigating the protective rate of EPF products against RPW in date plantations. [ABSTRACT FROM AUTHOR]

BACKGROUND: Rhynchophorus ferrugineus, the red palm weevil (RPW), is a key pest that attacks many economically important palm species and that has evolved a sensitive and specific olfactory system to seek palm hosts. Odorant‐binding proteins (OBPs) not only play crucial roles in its olfactory perception process but are also important molecular targets for the development of new approaches for pest management. RESULTS: Analysis of the tissue expression profiles of RferOBP8 and RferOBP11 revealed that these two Rhynchophorus ferrugineus odorant binding proteins (RferOBPs) exhibited high expression in the antennae and showed sexual dimorphism. We analyzed the volatiles of seven host plants by gas chromatography–mass spectrometry and screened 13 potential ligands by molecular docking. The binding affinity of two recombinant OBPs to aggregation pheromones and 13 palm odorants was tested by fluorescence competitive binding assays. The results revealed that eight tested palm volatiles and ferrugineol have high binding affinities with RferOBP8 or RferOBP11. Behavioral trials showed that these eight odor compounds could elicit an attraction response in adult RPW. RNA interference analysis indicated that the reduction in the expression levels of the two RferOBPs led to a decrease in behavioral responses to these volatiles. CONCLUSION: These results suggest that RferOBP8 and RferOBP11 are involved in mediating the responses of RPW to palm volatiles and to aggregation pheromones and may play important roles in RPW host‐seeking. This study also provides a theoretical foundation for the promising application of novel molecular targets in the development of new behavioral interference strategies for RPW management in the future. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Red palm weevil (RPW) (Rhynchophorus ferrugineus) threatens most palm species worldwide. This study investigated the molecular responses of coconut (Cocos nucifera) leaves to RPW infestation through metabolomics and transcriptomics analysis. An RPW insect attack model was developed by placing different RPW larval densitiesin coconut plants and measuring the relative chlorophyll content of different leaf positions and physiological indicators of dysfunction after RPW infestation. The metabolomic changes were detected in the leaves of 10, 20, 30, 40, and 50 days after infestation (DAI) using GC-MS. Certain metabolites (glycine, D-pinitol, lauric acid, allylmalonic acid, D-glucaro-1, 4-lactone, protocatechuic acid, alpha, and alpha-trehalose) were found to be possible indicators for distinct stages of infestation using metabolomics analysis. The influence on ABC transporters, glutathione, galactose, and glycolipid metabolism was emphasized by pathway analysis. Differentially expressed genes (DEGs) were identified at 5, 10, 15, and 20 DAI through transcriptomics analysis of infested coconut leaves, with altered expression levels under RPW infestation. The KEGG pathway and GO analysis revealed enrichment in pathways related to metabolism, stress response, and plant–pathogen interactions, shedding light on the intricate mechanisms underlying coconut–RPW interactions. The identified genes may serve as potential markers for tracking RPW infestation progression and could inform strategies for pest control and management.

In the present study, infective capabilities of two entomopathogenic nematode species including Heterorhabditis bacteriophora and Steinernema carpocapsae were evaluated against red palm weevil, under laboratory and field conditions. Bioassay experiments took place to estimate theLC50, LC90, LT50 and LT90 values. By H. bacteriophora treatment, theLC50's against the 2nd, 4th, 8th and 12th larval instars of R. ferrugineus were 909.48, 1623.00, 1771.08 and 2897.44 IJs/ml, respectively. The correspondent LC90 values were 3389.86, 6586.00, 8096.61 and 22548.21 IJs/ml, respectively after 15 days of treatment. Also, the LT50 values after using the concentration 2500 IJs/ml were 7.43, 9.54, 10.83 and 16.28 days, respectively, while those of LT90 were 21.81, 41.33, 52.68 and 116.40 days, respectively. By S. carpocapsae treatment, theLC50's were 728.97, 1370.00, 1547.21 and 2771.84 IJs/ml, respectively. LC90 values were 3507.36, 6784.74, 9293.00 and 18916.27 IJs/ml, respectively for the 2nd, 4th, 8th and 12th instars after 15 days of treatment. Also, the LT50 values after using the concentration 2500 IJs/ml were 7.04, 7.13, 10.16 and 14.62 days, respectively, while those of LT90 were 19.05, 22.57, 43.46 and 96.78 days, respectively. Whereas, the two species of EPN (H. bacteriophora and S. carpocapsae) by 2500 IJs/ml concentration caused 90 & 95% mortality for 2nd instar, 70 & 75% for 4th instar, 65 & 70% for 8th instar and 50 & 50% for 12th instar, respectively, 15 days after treatment. The field study showed that infested date palm trees injected by H. bacteriophora and S. carpocapsae by concentration 2 x 107 IJs/liter at the infestation site by the red palm weevil caused 60 and 80% recovery, respectively, recovery from infestation after 25 days of treatment. The study recommends using of S. carpocapsae to control the red palm weevil. [ABSTRACT FROM AUTHOR]

Laboratory experiments were conducted to study the effect of three diets on some biological aspects when the black earwig, Chelisoches morio feeds on newly deposited eggs, and first larval instar of the cotton leaf worm, ground cat's dry food and newly deposited eggs of the red palm weevil. Results indicated that the eggs incubation periods of Ch. morio were 6.62, 7.33 and 9.00 days by rearing on the three diets, respectively. A single mated female deposited 95.62, 80.93 and 120.03 eggs per female by rearing on the three diets, respectively. The hatchability percentage among the deposited eggs reached 87.11, 88.22 and 86.11%, respectively. The longest duration was that of the 4th instars (24.7 days), when feeding took place on RPW eggs, while the shortest period was 7.2 days, for the first instar by feeding also on RPW egg. The sex-ratios of females (%) were 60, 56 and 64% females, respectively. The pre-oviposition period of the females was 30.69, 35.27 and 33.01 days, while the oviposition period was 67.54, 56.06 and 55.03 days, for the same treatment, respectively. The post-oviposition was 52.23, 31.00 and 46.00 days, respectively. Nymphs of the 4th instar fed on 329.8 eggs of RPW, being the highest voracious feeder as compared to the first three nymphal instars which consumed the means of 11.1, 65.9 and 166.0 individuals, respectively. The feeding capacity of adults was 1223.6 for males and 1357.4 for females indicating that females were more voracious than male. The study recommends feeding on RPW eggs in mass rearing of the black earwig for biological control. [ABSTRACT FROM AUTHOR]

Red palm weevil (RPW), Rhynchophorus ferrugineus is an invasive insect pest of date palm (Phoenix dactylifera) and several other palm species. RPW causes heigh damage in most date-producing areas of the world, particularly in the Middle East and North Africa. In this study, we discussed the drastic effects of Origanum majorana essential oil on different parameters, including total hemocyte counts (THCs), differential hemocyte counts (DHCs), total protein, lipid, and carbohydrates, as well as some enzyme activity like catalase (CAT), phenol oxidase, super oxide dismutase (SOD),α β-estrase, and acetyl-cholinesterase (AChE) in RPW larvae. Groups of five fourth-stage larvae were submerged for 60 seconds immediately in 9.8% (LC50) of O. majorana. Compared to the control group, the THC levels are reduced after treatment with O. majorana essential oil. The estimated THCs were 27025 ±1356.54 cells/mm³ and 23250 ±1035.82 cells/mm³ for control and treated larvae, respectively. The DHCs showed that granulocytes (Gr) (26.47%) and plasmatocytes (Pl) (31%) were the two hemocyte types that predominated. Compared to the control group, the total protein, lipid, and carbohydrate were significantly lower. In comparison to control larvae, the treated larvae had significantly greater levels of CAT, SOD, and AChE activity. The activity levels of α, β-estrase and phenol oxidase were greatly decreased, but the phenol oxidase level was significantly increased in comparison to the control groups. Through the results obtained can be used Origanum majorana in the integrated control program especially in the period before harvest so that there are no residual pesticides in fruits when control palm after conducting some future studies infestation. [ABSTRACT FROM AUTHOR]

Abstract Botanical oils are considered ecofriendly compounds with insecticidal characteristics. In this study, the effects of basil (Ocimum basilicum), camphor (Cinnamomum camphora), cinnamon (Cinnamomum verum), lemon (Citrus limon), clove (Syzygium aromaticum), ginger (Zingiber officinale), black pepper (Piper nigrum), and orange (Citrus sinensis var balady) oil extracts on the survival of four entomopathogenic nematode strains belonging to the Steinernema and Heterorhabditis genera, as well as their impacts on Rhynchophorus ferrugineus egg hatching and larvae, were assessed. The results for the camphor, lemon, black pepper, and orange oils were promising as 50 μL/mL of each resulted in 0%, 0%, 16%, and 0% hatchability for the R. ferrugineus eggs, respectively. Furthermore, the mortality of R. ferrugineus larvae was up to 95% with the similar concentrations and an exposure time of 48 h, for the other investigated oils. Various morphohistopathological alterations were found in the cuticle; outer cuticle folds swelling or shrinkage and subcuticular muscle degeneration, as well as midgut; fat globules in the epithelial lining with marked degeneration and/or necrosis, of the R. ferrugineus larvae when compared with those of controls replicates. Mortality percentage of infective juveniles (IJs) of Steinernema carpocapsae (S2) was significantly lower than Heterorhabditis marelatus (D1), Steinernema riobravae (Sr) and Steinernema carpocapsae (All) when using camphor oil compared to the other oils (50%). From the obtained observations on oils lethal effects, the target of developing integral biocontrol product formulated from combinations of essential oils and nematode with insecticidal properties against R. ferrugineus (not nematode survival) is possible; a sustainable and ecofriendly product for pest management. [ABSTRACT FROM AUTHOR]

Insect-based food or ingredients have received tremendous attention worldwide because of their potential to ensure food and nutrition security, mitigating the reliance on land-dependent agricultural products. Indeed, insect-farming has low environmental impacts with reduced land, water and energy input. More importantly, insects are rich in high quality proteins and fats. They are also excellent sources of minerals, vitamins and bioactive compounds. Insect-based lipids are intriguing because they may contain high levels of unsaturated fatty acids particularly linoleic and α-linolenic acids. Besides, the insect-based lipids also show a considerable amount of bioactive components such as tocols, sterols and carotenoids. However, their fatty acid compositions and the nutritional values may vary depending on species, feed composition, developmental stage, geographical locations, and extraction techniques. Therefore, the present article aims to provide a comprehensive review on the fatty acid composition, the minor bioactive constituents and the physicochemical properties of fats and oils derived from insects of different orders (Coleoptera, Lepidoptera, Hymenoptera, Orthoptera, Hemiptera and Diptera). The various parameters affecting the nutritional compositions of the insect-based lipids will also be highlighted. These information will definitely provide a detailed insight on the potential applications of these fats in various food systems based on their unique properties. [ABSTRACT FROM AUTHOR]

Simple Summary: The red palm weevil is an exotic and highly endangered pest that is extremely harmful to palm plants. In order to effectively control this pest, we propose an algorithm to automatically detect and count adult red palm weevils in traps. Previously, the trapping and counting of adult red palm weevils was done manually. The population density and damage level were then inferred from the number of adults trapped to guide control efforts. However, the efficiency of this method is very low. The algorithm proposed in this paper solves the drawbacks of manual counting, and the recognition accuracy reaches 93.8%, which also improves the efficiency of agricultural monitoring. The red palm weevil (RPW, Rhynchophorus ferrugineus) is an invasive and highly destructive pest that poses a serious threat to palm plants. To improve the efficiency of adult RPWs' management, an enhanced YOLOv5 object detection algorithm based on an attention mechanism is proposed in this paper. Firstly, the detection capabilities for small targets are enhanced by adding a convolutional layer to the backbone network of YOLOv5 and forming a quadruple down-sampling layer by splicing and down-sampling the convolutional layers. Secondly, the Squeeze-and-Excitation (SE) attention mechanism and Convolutional Block Attention Module (CBAM) attention mechanism are inserted directly before the SPPF structure to improve the feature extraction capability of the model for targets. Then, 2600 images of RPWs in different scenes and forms are collected and organized for data support. These images are divided into a training set, validation set and test set following a ratio of 7:2:1. Finally, an experiment is conducted, demonstrating that the enhanced YOLOv5 algorithm achieves an average precision of 90.1% (mAP@0.5) and a precision of 93.8% (P), which is a significant improvement compared with related models. In conclusion, the enhanced model brings a higher detection accuracy and real-time performance to the RPW-controlled pest pre-detection system, which helps us to take timely preventive and control measures to avoid serious pest infestation. It also provides scalability for other pest pre-detection systems; with the corresponding dataset and training, the algorithm can be adapted to the detection tasks of other pests, which in turn brings a wider range of applications in the field of monitoring and control of agricultural pests. [ABSTRACT FROM AUTHOR]

This paper presents for the first time the design of a microwave sensing setup for the potential monitoring and identification of red palm weevil (RPW) gender type. The microwave sensor consists of a planar two-port transmission line (TL) with a single complementary split-ring resonant (CSRR) inclusion etched from the bottom metallic layer. The CSRR sensor is placed on top of a customized non-conductive container. The microwave sensing setup was designed, numerically demonstrated, fabricated and tested experimentally. Simulated results correlate quite well with the experimental data. Moreover, the sensitivity of the CSRR sensor when in close proximity to different RPW genders was evaluated both numerically and experimentally. Based on the measured results from 15 RPW samples with different body sizes, different RPW gender types showed unique microwave signatures. A notable shift in the sensor's resonance frequency was achieved, where on average a resonant frequency shift of 10% for adult RPWs was achieved, while a 2.4% frequency change was obtained for larvae (young) RPWs. Hence, the proposed microwave sensing setup can be adopted in field trials to examine and differentiate between various RPW genders at various developmental stages. [ABSTRACT FROM AUTHOR]

Red palm weevil (RPW) is a pest that can cause severe damage to plantations and affects palm trees. Classical approaches to detection depend on visual analysis, which is inaccurate and time-consuming. Hence, deep learning techniques emerge as a potential solution used for automating the process of detection and presenting efficient and precise results. The initial detection of the RPW remains a difficult task for good production as the identification will protect palm trees infected from the RPW. So advanced technologies like artificial intelligence (AI) and computer vision (CV) can be used in preventing the spread of the RPW on palm trees. Various scholars still working on identifying a precise method for the classification, identification, and localization of the RPW pest. This article develops an automated Red Palm Weevil Detection using Gorilla Troops Optimizer with Deep Learning (RPWD-GTODL) method. The goal of the presented RPWD-GTODL approach lies in the accurate detection and localization of the RPW effectually. To accomplish this, the presented RPWD-GTODL technique initially uses the Gabor filtering (GF) technique to pre-process the images. For RPW detection, the RPWD-GTODL technique uses a Mask RCNN object detector with MobileNetv2 as a backbone network. Moreover, the detection performance of the RPWD-GTODL technique can be boosted by the design of the GTO algorithm for the hyperparameter selection of the MobileNetv2 model. The performance validation of the RPWD-GTODL technique is tested using the RPW dataset and the results demonstrate the enhanced performance on RPW detection process with maximum accuracy of 99.27%.

Simple Summary: Red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier, 1790) is a highly invasive species of Southeast Asia and Melanesia origin that has spread widely in the Middle East and the Mediterranean area. Its larvae cause extensive damage to several palm species in the Arecaceae family, many of which are economically important for agricultural and ornamental purposes. For this reason, many studies are investigating sustainable and effective management strategies, including the Sterile Insect Technique (SIT). In this study, behavioral bioassays have been carried out in laboratory to evaluate if sterile RPW adult males are able to sexually compete with fertile males in no-choice and choice conditions. Results confirmed that irradiation does not induce any negative effects on the mating behavior and performance of sterile RPW males. Red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier 1790) is a highly invasive species originating from Southeast Asia and Melanesia. Over the past 30 years, this alien pest has spread extensively in the Middle East and the Mediterranean basin. Its endophagous larvae feed on various palm species, causing significant damage that leads to the death of palm trees. Controlling RPW infestations is challenging due to their gregarious nature and the lack of detectable early symptoms. Systemic insecticides are effective means of control, but their use in urban areas is prohibited and resistance can develop. Considering alternative options with minimal environmental impact, the Sterile Insect Technique (SIT) has been explored. Previous research has shown that male RPWs irradiated at 80 Gy or higher achieve full sterility. This study aimed to investigate in laboratory conditions whether RPW sterile males (irradiated at 60 and 80 Gy) could compete sexually with non-irradiate males. Laboratory bio-assays under both no-choice and choice conditions assessed sexual performance in terms of number of matings, mating duration and time elapsed until the first mating. The results confirmed that irradiation does not negatively affect the mating performance of sterile males, demonstrating their ability to compete successfully with non-irradiated males in both experimental setups. [ABSTRACT FROM AUTHOR]

Phoretic mites attach to different body parts of the red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier, 1790), to disperse. However, the question of how the patterns of attachment sites are formed remains intriguing. Here, we examined RPW‐associated phoretic mites in four districts in Northern Portugal (macrohabitat), and investigated the patterns of mite distribution on six body parts of RPW (microhabitat). At the macrohabitat level, we detected seven phoretic mite taxa using the RPW host in each of the four studied districts, all documented for the first time in association with this invasive exotic species in Portugal. However, their relative abundance (species evenness) varied between districts, as did species diversity. All examined weevils carried mites, and the prevalence of the different taxa did not differ between districts or sex of weevils. Measured by mean abundance and degree of aggregation, Centrouropoda sp. proved to be the dominant taxon, while Acarus sp. and Curculanoetus rhynchophorus were considered common subordinate taxa and Uroovobella sp., Mesostigmata, Nenteria extremica and Dendrolaelaps sp. sparse taxa. At the microhabitat level, all taxa were present on all body parts of the RPW; the highest abundance was in a region encompassing the inner surface of the elytra and the membranous hind wings (subelytral space). Analysis of niche overlap revealed that the distribution patterns of phoretic mite taxa on the RPW were not randomly structured. In the subelytral space, interspecific coexistence of mites increased as a function of body size difference with the dominant Centrouropoda sp. We found that in the subelytral space the large dominant species Centrouropoda sp. displaced the larger species Uroobovella sp. and the similarly sized species Nenteria extremica, but coexisted with smaller taxa. [ABSTRACT FROM AUTHOR]

Simple Summary: The red palm weevil poses a significant threat to palm species, resulting in substantial economic losses. While multiple methods have been developed to control its infestations, there is an urgent need for eco-friendly insecticides that selectively target its critical systems or pathways. One such target is its digestive system, which is essential for its survival. This review highlights the potential of using the digestive system of the red palm weevil to manage its infestations. Proteomic and transcriptomic data analyses on the weevils have provided a better understanding of the protein and gene compositions in its digestive system. With technological advancements, a more comprehensive approach can be taken to explore the opportunities in manipulating the data on the digestive system of red palm weevil, leading to improved management methods. Rhynchophorus ferrugineus, commonly known as red palm weevil (RPW), is a high-risk insect pest that has become a threat to many important palm species. There are several dominant factors that lead to the successful infestation of RPW, including its stealthy lifestyle, highly chitinized mouthpart, and high fecundity rate. Due to that, millions of dollars of losses have been suffered by many countries invaded by RPW. Several methods have been designed to control its invasion, including the usage of insecticides, but many cause resistance and environmental pollution. Therefore, an environmentally friendly insecticide that targets specific systems or pathways in RPW is urgently needed. One of the potential targets is the digestive system of RPW, as it is the major interface between the insect and its plant host. The related knowledge of RPW's digestive system, such as the anatomy, microflora, transcriptomic analysis, and proteomic analysis, is important to understand its effects on RPW's survival. Several data from different omics regarding the digestive systems of RPW have been published in separate reports. Some of the potential targets have been reported to be inhibited by certain potential insecticides, while other targets have not yet been tested with any inhibitors. Hence, this review may lead to a better understanding on managing infestations of RPW using the system biology approach for its digestive system. [ABSTRACT FROM AUTHOR]

Simple Summary: The red palm weevil beetle (Rhynchophorus ferrugineus), native to Asia, has assumed highly invasive behavior in the Mediterranean Sea basin, causing great damage to both date crops and ornamental plants. Given the lack of natural antagonists here, chemical substances must be administered to prevent attacks or cure infested palms. Through a multidisciplinary approach, we analyzed the evolution of the distribution of this beetle in San Benedetto del Tronto, a coastal city in central Italy rich in Canary Island date palms, considering both the control strategies used and their potentially negative effects. We observed that this beetle drastically reduced the palm stock by about half over the course of the 15 years between its arrival and the study's conclusion in 2020. The local municipality's program of chemical treatments has been very effective against new palm tree attacks but is expensive and poses toxicity risks for insects, animals, and the environment. However, currently, these treatments are the only effective tool for preserving the cultural landscape of this area. The challenge is to find the right balance between all these aspects. The fight against alien invasive insect pests of plants in the urban environment often affects varied sectors of the economy, landscape gardening, public health, and ecology. This paper focuses on the evolution of the red palm weevil in San Benedetto del Tronto, a coastal urban area in central Italy. We investigated the evolution of this insect pest of palm trees in the 2013–2020 period, considering both the effectiveness of the chemicals used and their potentially harmful effects. With a multidisciplinary approach, we carried out a spatio-temporal analysis of the extent and mode of pest spread over time using historical aerial photos, freely available remote sensing images, and field surveys integrated in a GIS environment. We also assessed the toxicity risk associated with the chemicals used to protect the palms from the red weevil. The fight against this weevil is now concentrated in specific areas such as parks, roads, villas, hotels, farmhouses, and nurseries. The preventive chemical treatments applied are very effective in preserving the palms, but they show a toxic potential for all organisms. We discuss current local management of this pest, focusing on several aspects involved in the fight against this beetle in an urban area. [ABSTRACT FROM AUTHOR]

Simple Summary: This study aimed to explore the effectiveness of a new microbial formulation that utilizes the entomopathogenic fungus, Metarhizium anisopliae, in controlling the red palm weevil (RPW), Rhynchophorus ferrugineus, which is the most destructive insect pest of major cultivated palms. Previously, we published the development of an oil-emulsion formulation system to enhance the biological performance of this particular fungal isolate. The system improved the stability, replicability, shelf life, and resistance to heat stress and UV irradiation. The current results reveal that the formulation has improved fungal bioefficacy and pathogenicity through direct and indirect contact bioassays. The lethal infection of formulated conidia against RPW was more effective and dispersed better than the aqueous suspension of non-formulated conidia. The spread of disease can be observed from a treated individual to a healthy RPW upon contact, which explains the disease-spreading ability of formulated conidia. Additionally, the infections were confirmed through both morphological analysis and DNA sequencing. The results showed that the RPWs were exclusively infected by M. anisopliae throughout the experiments. Therefore, this oil-emulsion formulated conidia could be incorporated into current integrated pest management programs to achieve more promising biocontrol outcomes in the long-term application of sustainable agricultural practices. The red palm weevil (RPW), Rhynchophorus ferrugineus, poses a severe threat to agro-industrial crops, particularly major cultivated palm species. Infestations result in economic losses due to reduced fruit quality and yield. The entomopathogenic fungus, Metarhizium anisopliae, has shown promise as a potential biocontrol agent against the RPW. However, the use of an emulsion formulation of M. anisopliae for managing this serious insect pest has yet to be fully explored. The oil-emulsion formulation containing this entomopathogen may enhance the conidia's stability, prolong its lifetime, and reduce the impact of heat stress or UV irradiation on the fungus. Therefore, this study aimed to investigate the bioefficacy of a new oil-in-glycerol emulsion formulation on mycoinsecticidal activity against RPW adults by direct and indirect bioassays. Results showed that conidia concentration was directly proportional to the RPW mortality percentage. The LT50 of 8.183 days was achieved by the conidial formulation against RPW, with a significantly lower LC50 (1.910 × 105 conidia mL−1) compared to the aqueous conidia suspension (LT50 = 8.716 days; LC50 = 7.671 × 105 conidia mL−1). Indirect bioassays revealed that the oil-in-glycerol emulsion had a disease-spreading ability that resulted in up to 56.67% RPW mortality. A zero E-value reading indicates that the DNA sequence being studied is highly similar to that of the fungal species M. anisopliae, which has been identified in the NCBI database. Although the new emulsion formulation has improved the efficacy and pathogenicity of M. anisopliae in vitro, it is important to also consider the fungal pathogen's compatibility with other agricultural practices to prevent any loss of control efficiency in the actual usage environment. [ABSTRACT FROM AUTHOR]

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Simple Summary: The red palm weevil Rhynchophorus ferrugineus is an invasive pest insect that feeds on more than 20 species of palms, many of which are widely grown for food and ornamental use. Due to its vast spread and the huge economic damage this pest can cause, it is very important to find sustainable and effective eradication strategies. Sterile insect techniques are biological control approaches based on the release of mass-reared sterilized males that could improve the likelihood of successful pest control. However, for the successful implementation of these approaches, it is necessary to develop a deep understanding of the insect's mating system. For this purpose, we built a paternity assignment strategy based on previously developed microsatellite loci to help the future study of the reproductive mechanisms of this species in laboratory-controlled mating experiments. We evaluated the reliability of our genetic tool using a simulation approach that aimed to explore its resolution power in paternity tests, both in the laboratory and in nature. The red palm weevil Rhynchophorus ferrugineus is an invasive pest from southeastern Asia and Melanesia that has spread widely across the Middle East and the Mediterranean Basin over the last 30 years. Its endophagous larvae cause huge amounts of damage to several palm tree species from the Arecaceae family. Many of these palms are economically important for agricultural and ornamental purposes. Therefore, a lot of attention has recently been focused on studying this species with the aim of identifying sustainable and effective eradication strategies. Sterile insect techniques are biological control strategies that are currently being investigated for their potential to eradicate this pest in selected invasion areas. Mating system features (e.g., polyandry and related features) can affect the success and suitability of these approaches. The main goal of this research was to assess the performance of a previously developed microsatellite panel in terms of the paternity assignment of progeny from laboratory mating experiments. Using a simulation approach, we evaluated the reliability of the microsatellite markers in the paternity tests both in complex laboratory experiment scenarios and on the progeny of wild-caught gravid females to help future studies on the RPW mating system. As a case study of the simulation results, we performed two double-mating experiments, genotyped the progeny and estimated the P2 values to compare to the expected progeny genotypes according to the crossing scheme of each experiment. The results of our simulations on laboratory experiments showed that it was possible to carry out paternity assignments for all progeny with reliable statistical confidence using our 13 microsatellites set. On the contrary the low genetic variability measured in red palm weevil populations in invaded areas made the resolution power of our loci too low to carry out paternity analyses on natural populations. Results of laboratory crossing were completely congruent with the expectations from the Mendelian laws. [ABSTRACT FROM AUTHOR]

Simple Summary: The red palm weevil (RPW) Rhynchophorus ferrugineus (Coleoptera: Curculionidae) is a species of beetle that depends on palm trees to complete its life cycle. RPW larvae feed on the palm tree trunk and can result in tree death, thus having a major impact on both wild and cultivated palm trees in several countries. The resulting economic and biodiversity losses caused by invasive populations of the RPW gave it a major pest status, and now governments, companies, and researchers across multiple countries are interested in developing effective control strategies to prevent further damage. Managing agricultural pests in the face of pressures such as climate change, rising levels of insecticide resistance, and increasing demands for food production will require advanced knowledge of pest biology. In this review, after presenting basic aspects of RPW biology and pest status, we gather information on the use of omics technologies, such as transcriptomics, genomics, and metagenomics, and explore their achievements and potentials to illuminate RPW biology and improve management. We finalize the review by exploring current opportunities and challenges in the use of these technologies for RPW management. The red palm weevil (RPW), Rhynchophorus ferrugineus (Coleoptera: Curculionidae), is the most devastating pest of palm trees worldwide. Mitigation of the economic and biodiversity impact it causes is an international priority that could be greatly aided by a better understanding of its biology and genetics. Despite its relevance, the biology of the RPW remains poorly understood, and research on management strategies often focuses on outdated empirical methods that produce sub-optimal results. With the development of omics approaches in genetic research, new avenues for pest control are becoming increasingly feasible. For example, genetic engineering approaches become available once a species's target genes are well characterized in terms of their sequence, but also population variability, epistatic interactions, and more. In the last few years alone, there have been major advances in omics studies of the RPW. Multiple draft genomes are currently available, along with short and long-read transcriptomes, and metagenomes, which have facilitated the identification of genes of interest to the RPW scientific community. This review describes omics approaches previously applied to RPW research, highlights findings that could be impactful for pest management, and emphasizes future opportunities and challenges in this area of research. [ABSTRACT FROM AUTHOR]

Red palm weevil (RPW) is widely considered a key pest of palms, creating extensive damages to the date palm trunk that inevitably leads to palm death if no pest eradication is done. This study evaluates the potential of a remote sensing approach for the timely and reliable detection of RPW infestation on the palm canopy. For two consecutive years, an experimental field with infested and control palms was regularly monitored by an Unmanned Aerial Vehicle (UAV) carrying RGB, multispectral, and thermal sensors. Simultaneously, detailed visual observations of the RPW effects on the palms were made to assess the evolution of infestation from the initial stage until palm death. A UAV-based image processing chain for nondestructive RPW detection was built based on segmentation and vegetation index analysis techniques. These algorithms reveal the potential of thermal data to detect RPW infestation. Maximum temperature values and standard deviations within the palm crown revealed a significant (α = 0.05) difference between infested and non-infested palms at a severe infestation stage but before any visual canopy symptoms were noticed. Furthermore, this proof-of-concept study showed that the temporal monitoring of spectral vegetation index values could contribute to the detection of infested palms before canopy symptoms are visible. The seasonal significant (α = 0.05) increase of greenness index values, as observed in non-infested trees, could not be observed in infested palms. These findings are of added value for steering management practices and future related studies, but further validation of the results is needed. The workflow and resulting maps are accessible through the Mapeo® visualization platform. [ABSTRACT FROM AUTHOR]

Smart agriculture and Internet of Things (IoT) technologies have become the key points for many intelligent decision-making applications to support agricultural experts and farmers, especially for crop pest management and control. In this work, we present an IoT-based sound detection model for identifying red palm weevil (RPW) larvae to protect date palm trees at the early stage of infestation. The proposed detection system is mainly based on a modified mixed depthwise convolutional network (MixConvNet) as a recent deep learning classifier. The public TreeVibes dataset, which contains short audio recordings of feeding and/or moving RPWs, was successfully tested and assessed with the proposed MixConvNet classifier. There were 146 and 351 specimens of infested and clean sounds examined, respectively. The classification results showed that our proposed MixConvNet is efficient and superior to other deep learning classifiers, such as Xception and residual network (Resnet) models in previous related studies, obtaining the best accuracy score of 97.38. Moreover, the MixConvNet classifier is capable of identifying RPW infestation cases precisely with a high accuracy value of 95.90% ± 1.46, using 10-fold cross-validation. Therefore, practical implementation of our proposed IoT-enabled early sound detection system of RPWs is considered the future milestone of this study.

Abstract Background The red palm weevil (RPW), Rhynchophorus ferrugineus (Coleoptera: Curculionidae), overruns date palm ranches in most Oases of Saudi Arabia and causes massive economic losses. Integrated pest management (IPM) of the RPW by biocontrol agents of bacterial isolates was the primary aim of the present study. Results Thirty-seven bacterial isolates were isolated from the larvae of R. ferrugineus, which were collected from infested Phoenix dactylifera trees growing in different parts of Saudi Arabia. 16S rDNA sequencing showed that the isolated bacteria were: Serratia marcescens , Klebsiella pneumoniae and Bacillus thuringiensis. The potential of these isolates was tested against R. ferrugineus in the laboratory. The use of these three isolates showed significant mortality percentages against R. ferrugineus. The highest reduction in mortality was recorded at the concentration of 1 × 108 CFU/ml; B. thuringiensis isolate displayed the highest potency in mortal percentage rate (100%), 4 days post-treatment, followed by S. marcescens isolate after 5 days, and then K. pneumoniae isolate after 6 days. Conclusions These results suggest that the use of these bacterial isolates was very useful in in vitro experiments, and it may consider those bacterial strains of interest as a potential biocontrol agent of R. ferrugineus.

Red palm weevil (RPW, Rhynchophorus ferrugineus) is an invasive pest of palms. In China, coconut (Cocos nucifera) production is being significantly affected by the RPW attack. To develop a long-term RPW control strategy, host-plant resistance is the most sustainable option. In this regard, the availability of transcriptome sequencing data from RPW-infected coconut plants can be highly useful. Therefore, the present study assessed coconut leaf physiological responses and transcriptional changes after different days of RPW attack i.e., 5, 10, 15, 20, and 25 days after infestation (DAI). A comparison of physiological data indicated that populations with the higher number of RPW insects i.e., population C (15 males +21 females) and D (20 males +28 females) triggered higher antioxidant enzyme activities. We used this data to study the transcriptomic responses on 5 and 20 DAI. Of the 38,432 detected transcripts, 3,984, 1,981, 3,925, and 2,257 were differentially expressed in CK (control/no RPW)_vs._C (5 DAI), CK_vs._D (5 DAI), CK_vs._C (20 DAI), and CK_vs._D (20 DAI), respectively. These transcripts were enriched in plant-pathogen interaction, phenylpropanoid/flavonoid biosynthesis, amino sugar and nucleotide sugar metabolism, plant hormone signal transduction, mitogen-activated protein kinase, and reactive oxygen scavenging pathway. We discuss these results and present several candidate genes to be manipulated for developing a sustainable strategy to control RPW attack regarding host-plant resistance. Furthermore, these findings provide a basis for developing effective early and late RPW attack detection strategies.

Infesting a variety of palm trees throughout Egypt, the Red Palm Weevil (RPW), Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae), is regarded as a damaging pest. The objective of the current study was to determine the protein pattern while evaluating six essential oil emulsions as botanical extracts against this pest in a laboratory setting. The method of dipping food was used at concentrations of 2, 3, 4, 5 and 6%. There were notable variations between the various oils and exposure times. The studied oils showed varying fatality rates in response to increasing concentrations. Across all concentrations, the lowest mortality was obtained with citronella oil. After 96 hours, 6% of the clove and orange oils caused 100% death. Totally 90% of insect died when exposed to 4% concentration of chili oil. Even though the tested oils had different fatality rates, longer exposure times resulted in larger percentages. The molecular weights of the bands varied and ranged from 7 to 275 KD in the treated hemolymph and from 6 to 273 KD in the untreated hemolymph, indicating significant variations between the two types of hemolymph. It is stated that essential oils are a good choice for RPW control approaches, as long as the suitable type of oil is used, taking into account exposure time and oil concentration. [ABSTRACT FROM AUTHOR]

The red palm weevil (RPW), Rhynchophorus ferrugineus, is widely considered to be highly invasive and the most damaging insect pest affecting palms in the world. Nonetheless, the prevention or significant slowing of the spread of RPW mainly relies on the application of integrated pest management (IPM) programs. This study aimed to evaluate farmers' adoption of RPW IPM practices and examine the differences in adoption according to the farmers' socio-economic attributes and their farm characteristics. The data were collected from 156 farmers through structured questionnaires by the Al-Kharaj governorate, Saudi Arabia. The findings showed that the farmers moderately adopted the categories of legislative control (54.77%) and cultural practices (50.44%), whereas they were showed a low-level adoption regarding the prevention, mechanical control, and chemical control categories. The cluster analysis revealed two variable farmer segments, "low adopters" and "moderate adopters", based on the average level of adoption of the 23 IPM practices examined. The cluster of "moderate adopters" accounted for 57.1% of the samples and had a higher average adoption in terms of all the practices investigated. Significant differences (p < 0.01) were found between the two groups of farmers, corresponding to their age, education level, farm size, farming experience, number of date palm trees on the farm, off-farm income, farming activities, source of irrigation, type of irrigation, growing of the 'Khodri' cultivar, growing of the 'Barhi' cultivar, and tree spacing. The results suggest that implementing campaigns to increase public awareness of the consequences resulting from the non-adoption of IPM, enhancing the participation of date palm farmers in the area-wide IPM strategy, and improving recognition behavior by detecting RPW with digital devices are useful actions. [ABSTRACT FROM AUTHOR]

Our study's overarching goal was to determine which O. basilicum cell suspensions approach yielded the most insecticidal and R. ferrugineus-inhibitory volatile secondary metabolites. After inoculation with Verticillium dahliae as an activator, the growth kinetics were measured, and the extract was identified using GC-MS. Validation was achieved for the insecticidal efficacy of a volatile extract, the pure phenolic content against larva and adult R. ferrugineus, and the inhibitory effect on proteases (in vivo and in vitro). The volatile extract achieved an LC50 of 1229 µg/mL and an LD50 of 13.8 µg/larva. The LC50 values for β-bergamotene, α-eudesmol, β-farnesene, linalool, 1,8-cineole, eugenol, α-guaiene, and β-caryophyllene were 1294, 1312, 1356, 1398, 1426, 1459, 1491, and 1523 g/mL, respectively. The LD50 activities of α-eudesmol, linalool, 1,8-cineole, eugenol, and nerol were 12.4, 13.7, 13.9, 14.2, and 15.6 g/larva, respectively. Active volatile extract of O. basilicum inhibited trypsin proteinase, elastase, cysteine, overall protease, and metalloprotease activity with IC50 values of 89.4, 101.7, 394.7, 112.4, and 535.2 µg/mL and 178.5, 192.4, 547.3, 208.3, and 924.8 µg/mL, in vitro and in vivo, respectively. There was evidence of action against total proteases (in vitro) with IC50 values of 78.9, 81.2, 88.6, 90.7, 91.5, 97.6, 107.4, and 176.3 µg/mL for β-bergamotene, α-eudesmol, β-farnesene, linalool, 1,8-cineole, eugenol, α-guaiene, and β-caryophyllene, respectively. Total proteases (in vivo) are inhibited by the α-eudesmol, linalool, 1,8-cineole, eugenol, nerol, and (E)-β-ocimene, with IC50 values of 162.3, 192.7, 193.1, 201.4, 248.6, and 273.2 µg/mL, respectively. ADMET and molecular docking modeling were the only two methods used to conduct in-depth computational analyses of compounds. The study recommended using an efficient cell suspension method to produce a volatile extract rich in useful secondary metabolites that may be utilized as a bio-insecticide. [ABSTRACT FROM AUTHOR]

Simple Summary: Rynchophorus ferrugineus Olivier, the red palm weevil (RPW), is a damaging insect that often severely infests palm trees. Since insecticides have a detrimental environmental impact and may lead to pesticide resistance, new biological control methods are needed. Bacteria from many different species affect the RPW larval growth, health, and immunity. The work evaluates the crosstalk between the RPW and rhizosphere bacteria. Four bacterial isolates, three belonging to Bacillus cereus and one belonging to B. thuringiensis, had a significantly higher impact on the mortality of the larvae and adults of the RPW than other bacteria that were tested did. The results emphasize the significant potential of developing new microbial resource-based management techniques for this pest. The Red Palm Weevil (Rhynchophorus ferrugineus (Oliv.) (Coleoptera, Dryophthoridae) is a well-known palm tree pest that has caused enormous economic damage all over the globe. Insecticides are still the primary method of controlling this pest at this period. However, field populations of RPW have been shown to be resistant to pesticides. Using Bacillus spp. might be one of the options for controlling R. ferruginous. In this study, 23 species of Bacillus spp. were isolated from the rhizosphere of date palm trees in Al Ahsa Oasis, Saudi Arabia. The isolates were identified using 16S rRNA gene sequencing. R. ferrugineus larvae and adults were tested on sugarcane pieces that were treated with the B. thuringiensis strain PDC-AHSAA1 and B. cereus strains (PDC-AHSAA2, PDC-AHSA3 and PDC-AHSA4). The LC50 values for larvae and adults were quite low when they were compared with those of the other isolated strains. The B. thuringiensis strain PDC-AHSAA1 was more effective against both the larvae and adults. The determined LC50 values for B. thuringiensis ranged from 4.19 × 107–3.78 × 109. After 21 days, the data on larval mortality and body weight were evaluated. The surviving larvae that were treated with the bacterial isolates did not acquire a substantial weight. For the RPW larvae and adults, the mortality and corrected mortality death rates were increased by increasing the concentration of B. thuringiensis. In conclusion, Bacillus-treated diets negatively influenced the growth and development of the RPW. This research reported on the interaction between the RPW and the rhizosphere Bacillus spp. and highlighted the tremendous potential for the development of microbial resource-based control strategies for this pest. [ABSTRACT FROM AUTHOR]

Weevils, classified in the family Curculionidae (true weevils), constitute a group of phytophagous insects of which many species are considered significant pests of crops. Within this family, the red palm weevil (RPW), Rhynchophorus ferrugineus, has an integral role in destroying crops and has invaded all countries of the Middle East and many in North Africa, Southern Europe, Southeast Asia, Oceania, and the Caribbean Islands. Simple sequence repeats (SSRs), also termed microsatellites, have become the DNA marker technology most applied to study population structure, evolution, and genetic diversity. Although these markers have been widely examined in many mammalian and plant species, and draft genome assemblies are available for many species of true weevils, very little is yet known about SSRs in weevil genomes. Here we carried out a comparative analysis examining and comparing the relative abundance, relative density, and GC content of SSRs in previously sequenced draft genomes of nine true weevils, with an emphasis on R. ferrugineus. We also used Illumina paired-end sequencing to generate draft sequence for adult female RPW and characterized it in terms of perfect SSRs with 1–6 bp nucleotide motifs. Among weevil genomes, mono- to trinucleotide SSRs were the most frequent, and mono-, di-, and hexanucleotide SSRs exhibited the highest GC content. In these draft genomes, SSR number and genome size were significantly correlated. This work will aid our understanding of the genome architecture and evolution of Curculionidae weevils and facilitate exploring SSR molecular marker development in these species. [ABSTRACT FROM AUTHOR]

Red palm weevil (RPW) is a harmful pest that destroys many date, coconut, and oil palm plantations worldwide. It is not difficult to apply curative methods to trees infested with RPW; however, the early detection of RPW remains a major challenge, especially on large farms. In a controlled environment and an outdoor farm, we report on the integration of optical fiber distributed acoustic sensing (DAS) and machine learning (ML) for the early detection of true weevil larvae less than three weeks old. Specifically, temporal and spectral data recorded with the DAS system and processed by applying a 100–800 Hz filter are used to train convolutional neural network (CNN) models, which distinguish between "infested" and "healthy" signals with a classification accuracy of ∼97%. In addition, a strict ML-based classification approach is introduced to improve the false alarm performance metric of the system by ∼20%. In a controlled environment experiment, we find that the highest infestation alarm count of infested and healthy trees to be 1131 and 22, respectively, highlighting our system's ability to distinguish between the infested and healthy trees. On an outdoor farm, in contrast, the acoustic noise produced by wind is a major source of false alarm generation in our system. The best performance of our sensor is obtained when wind speeds are less than 9 mph. In a representative experiment, when wind speeds are less than 9 mph outdoor, the highest infestation alarm count of infested and healthy trees are recorded to be 1622 and 94, respectively. [ABSTRACT FROM AUTHOR]