•Increased fish oil (FO) intake led to a rise in ω-3 fatty acid in SPWL.•Health-promoting indices of SPWL lipid improved when fed FO-fortified diets.•SPWL fed a 1.5 % FO-fortified diet had higher ...fat, protein, and mineral content.•3–5% FO had a negative impact on nutritional value and growth performance of SPWL.
The nutritional values of sago palm weevil larvae (SPWL) reared on mixed plant-based diets (ground sago palm trunk (GS), cornmeal, rice bran, soybean, and perilla seed), containing different levels of dietary fish oil (FO) were compared to those reared on commercial pig feed (PF) and GS. Increased FO content resulted in an increase in ω-3 fatty acids (FA) in SPWL (p < 0.05), especially α-linolenic acid and eicosapentaenoic acid. When fed FO-fortified diets instead of PF, the health-promoting indices of the SPWL lipid improved significantly (e.g., decreased ω-6/ω-3 ratio, thrombogenicity index, and hypercholesterolemic FA with increased PUFA content). The lipid, protein, and mineral contents of SPWL were increased while growth performance was maintained on a 1.5% FO-fortified diet. Higher FO levels (3–5%) had a negative impact on the nutritional values and growth performance of the SPWL. Thus, there was a reasonable chance of developing a high-nutrient alternative insect for human consumption.
Palm trees are of immense economic, sociocultural, touristic, and patrimonial significance all over the world, and date palm‐related knowledge, traditions, and practices are now included in UNESCOs ...list of the Intangible Cultural Heritage of Humanity. Of all the pests that infest these trees, the red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier), is its primary enemy. The RPW is a category‐1 quarantine insect pest that causes enormous economic losses in palm tree cultivation worldwide. The RPW synchronizes mass gathering on the palm tree for feeding and mating, regulated by a male‐produced pheromone composed of two methyl‐branched compounds, (4RS, 5RS)‐4‐methylnonan‐5‐ol (ferrugineol) and 4(RS)‐methylnonan‐5‐one (ferrugineone). Despite the importance of odorant detection in long‐range orientation towards palm trees, palm colonization, and mating, the pheromone receptor has not been identified in this species. In this study, we report the identification and characterization of the first RPW pheromone receptor, RferOR1. Using gene silencing and functional expression in Drosophila olfactory receptor neurons, we demonstrate that RferOR1 is tuned to ferrugineol and ferrugineone and binds five other structurally related molecules. We reveal the lifetime expression of RferOR1, which correlates with adult mating success irrespective of age, a factor that could explain the wide distribution and spread of this pest. As palm weevils are challenging to control based on conventional methods, elucidation of the mechanisms of pheromone detection opens new routes for mating disruption and the early detection of this pest via the development of pheromone receptor‐based biosensors.
Dryophthorinae is an economically important, ecologically distinct, and ubiquitous monophyletic group of pantropical weevils with more than 1,200 species in 153 genera. This study provides the first ...comprehensive phylogeny of the group with the aim to provide insights into the process and timing of diversification of phytophagous insects, inform classification and facilitate predictions. The taxon sampling is the most extensive to date and includes representatives of all five dryophthorine tribes and all but one subtribe. The phylogeny is based on secondary structural alignment of 18S and 28S rRNA totaling 3,764 nucleotides analyzed under Bayesian and maximum likelihood inference. We used a fossil‐calibrated relaxed clock model with two approaches, node‐dating and fossilized birth‐death models, to estimate divergence times for the subfamily. All tribes except the species‐rich Rhynchophorini were found to be monophyletic, but higher support is required to ascertain the paraphyly of Rhynchophorini with more confidence. Nephius is closely related to Dryophthorini and Stromboscerini, and there is strong evidence for paraphyly of Sphenophorina. We find a large gap between the divergence of Dryophthorinae from their sister group Platypodinae in the Jurassic‐Cretaceous boundary and the diversification of extant species in the Cenozoic, highlighting the role of coevolution with angiosperms in this group.
This study presents the first phylogeny of the palm weevil subfamily Dryophthorinae (1,200 species, 153 genera), a group that is mainly associated with monocots and includes major pests, such as the Red and South American Palm Weevils. This study includes genetic sampling of all major lineages worldwide, integrated structural alignment of ribosomal DNA and cutting‐edge fossil‐calibrated dating analyses. Major findings include confirmation of an unstable classification system; weak and unreliable diagnostic characters, and diversification coinciding with the dominance of flowering plants. The phylogeny enables pest management personnel and researchers to not only make solid predictions about potential new pests, unknown host associations, potential vectors of invasives, endosymbionts, and natural enemies, but also provides insights into the complicated process of diversification of phytophagous insects.
The Red Palm Weevil (RPW), also known as the palm weevil, is considered among the world’s most damaging insect pests of palms. Current detection techniques include the detection of symptoms of RPW ...using visual or sound inspection and chemical detection of volatile signatures generated by infested palm trees. However, efficient detection of RPW diseases at an early stage is considered one of the most challenging issues for cultivating date palms. In this paper, an efficient approach to the early detection of RPW is proposed. The proposed approach is based on RPW sound activities being recorded and analyzed. The first step involves the conversion of sound data into images based on a selected set of features. The second step involves the combination of images from the same sound file but computed by different features into a single image. The third step involves the application of different Deep Learning (DL) techniques to classify resulting images into two classes: infested and not infested. Experimental results show good performances of the proposed approach for RPW detection using different DL techniques, namely MobileNetV2, ResNet50V2, ResNet152V2, VGG16, VGG19, DenseNet121, DenseNet201, Xception, and InceptionV3. The proposed approach outperformed existing techniques for public datasets.
•Efficient approach for early detection of Red Palm Weevil (RPW).•Recording and analyzing RPW sound activities.•Applying different deep learning techniques to classify palms as infested and not infested.•Monitoring palm farms to detect early signs of RPW infection.•Several experiments are conducted using real-world and public datasets.
Red Palm Weevil (RPW), Rhynchophorus ferrugineus, is a serious pest of palms throughout South and Southeast Asia which are the native habitat of this pest. The aim of this study was to assess ...survival and fertility characteristics of the Red Palm Weevil(RPW),R. ferrugineus in the laboratory. Life tables and population parameters of the RPW were constructed on sugarcane slices as a course food for RPW under laboratory conditions. The results showed that the highest mortality occurred in 12thinstar. The life table analysis showed that the population density of RPW decreased gradually. The survival ratio of male to female was 0.396:0.604. The females lived for a maximum of 196 days. The highest number of eggs produced per female per day was 5. The intrinsic rate of increase (rm) in egg production per female per day was 0.17 and the daily finite of increase (λ) was 1.19 females per female per day, with a mean generation time (T) of 25.15 days. The net reproductive rate (Ro) of the population was 70.18. The population doubling time (DT) was 4.8 days.
Aromatic esterases from the red palm weevil; Rynchophorus ferrugineus 5th instar larvae were partially fractionated using differential centrifugation technique to study some enzyme properties and ...possible use of some inorganic salts as enzyme inhibitors hoping for future use in the field of pest control. Cytosol soluble fraction contained most of esterases activity. Esterases catalysis was activated by organic solvents such as acetone. However, incubation of esterases with 100 μl of different molar concentrations of EDTA, CuSO4, NaF, CaCl2 and NaCl for 10 min at 25 °C had variable effects. NaCl had no effect, but CaCl2 showed some considerable activation. CuSO4 was the strongest inhibitor for both α- and β-esterases catalysis, but β-esterases were more inhibited than α-esterases by the tested CuSO4 concentrations. In vitro partial inhibition kinetics studies showed that IC50 of CuSO4 was 8.5 and 4.4mM for α- and β-esterases of the red palm weevil larvae, respectively. CuSO4 was a competitive inhibitor for esterases. The Dixon plot analysis revealed that CuSO4 had a dissociation constant (ki) value of 4 and 2 mM for α - and β-esterases from cytosol fractions, respectively. On the other hand, the Arrhenius plot showed that activation energy (Ea) was 14.92 and 24.89 kJ/mol for α- and β-esterases hydrolysis reactions. i.e. esterases from 5th instar larvae of R. ferrugineus had minimum activation energy to start naphthyl acetate hydrolysis. Studies must be extended to explore CuSo4 activity in the field of pest control and the possibility of using it as insecticide synergist.
The foraging behaviour of bacteria in colonies exhibits motility patterns that are simple and reasoned by stimuli. Notwithstanding its simplicity, bacteria behaviour demonstrates a level of ...intelligence that can feasibly inspire the creation of solutions to address numerous optimisation problems. One such challenge is the optimal allocation of tasks across multiple unmanned aerial vehicles (multi-UAVs) to perform cooperative tasks for future autonomous systems. In light of this, this paper proposes a bacteria-inspired heuristic for the efficient distribution of tasks amongst deployed UAVs. The usage of multi-UAVs is a promising concept to combat the spread of the red palm weevil (RPW) in palm plantations. For that purpose, the proposed bacteria-inspired heuristic was utilised to resolve the multi-UAV task allocation problem when combating RPW infestation. The performance of the proposed algorithm was benchmarked in simulated detect-and-treat missions against three long-standing multi-UAV task allocation strategies, namely opportunistic task allocation, auction-based scheme, and the max-sum algorithm, and a recently introduced locust-inspired algorithm for the allocation of multi-UAVs. The experimental results demonstrated the superior performance of the proposed algorithm, as it substantially improved the net throughput and maintained a steady runtime performance under different scales of fleet sizes and number of infestations, thereby expressing the high flexibility, scalability, and sustainability of the proposed bacteria-inspired approach.
•A new algorithm for autonomous task allocation in multi-UAVs missions is proposed.•A well-controlled experimental framework for evaluating the proposed algorithm is developed.•The proposed algorithm is investigated against four benchmark algorithms.•The results show significant improvements in considered measures.
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•Four potential entomopathogenic fungal isolates were selected to control RPW.•The EPFs (JEF-484 and JEF-158) have good conidia production and thermotolerance.•Two promising EPFs were ...conducted to the bioassay of RPW egg and larvae.•Two promising EPFs showed ovicidal effect and dosage effect against RPW larvae.•Combine two promising EPF isolates might apply on the controlling of RPW.
The red palm weevil (RPW), Rhynchophorus ferrugineus, is an important pest of palms, and difficult to control by conventional methods. Therefore, microbial control is an alternative strategy for controlling RPW. Herein, a total of 15 entomopathogenic fungi (EPFs) were subjected to primary pathogenicity screening against last stage of RPW larvae. The preliminary data showed that four Beauveria bassiana isolates (JEF-484, 158, 462 and 507) and one Isaria fumosorosea isolate (JEF-014) resulted in 100 % mortality within 5–10 days post inoculation (d.p.i.), respectively. According to the time required for RPW mortality, JEF-484, 158, 462 and 014 were further subjected to bioassays using 107 conidia/ml suspensions by spraying method. Based on the results, JEF-484 showed the highest mortality and shortest LT50 on the last stage of RPW larvae, followed by JEF-158. The two isolates also showed good conidial production and high thermal stability compared to the other isolates. Therefore, JEF-484 and JEF-158 were selected for bioassays against RPW egg and the last larval stage with different concentrations of 105, 106 and 107 conidia/ml conidial suspensions by spraying method. For the bioassay at the egg stage, JEF-158 showed a significantly higher ovicidal effect than JEF-484. In the larval bioassay, both EPF isolates showed a dosage-dependent effect on the RPW larvae. JEF-484 caused higher mortality in RPW larvae than JEF-158. In summary, the combination of the 2 promising EPF isolates might provide an opportunity for the practical microbial control of RPW at different life stages in palm tree fields.
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.
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