The bean weevil (Acanthoscelides obtectus (Say.)) is one of the main pests of stored beans in the world. Heterogeneous Inbreed Families (HIF) Population of Near Isogenic Lines (NILs) could be an exceptional strategy to study the inheritance of the resistance against A. obtectus. We developed a HIF population of NILs of R-bufa-80-12 (Phaseolus vulgaris) to study the inheritance related to bean weevil resistance and to search NILs with high resistance to the pest within the HIF population. The objective of this research was to study the inheritance in a HIF population and to identify the best lines to provide weevil resistance in bean breeding for commercial genotypes that could reduce pesticide applications. To achieve this objective, we developed a set of 148 NILs which were near-homozygous in the genome, except in the region under study. The HIF were evaluated in two environments under natural infestation with A. obtectus in free choice bioassays in a warehouse highly infested. The population showed wide variability for the traits studied, from 17.2 to 29.2 g for 100 seed weight, 0.0-0.8 for consumption in grams, 2.0-30.0 for consumption in percent and 1.2-9.6 for preference (number of adults in the bottle to the end of the experiments. The heritabilities for resistance traits were from very low to low 0.0 to 0.19. The heritability for 100 seed weight was the highest, with a value of 0.90. All traits studied in this research have a normal distribution, so they are considered to be quantitatively inherited. However, a great variability was found for the traits studied, which allows selecting lines with a high level of resistance within the R-bufa-80-12 HIF population. All traits studied in present research are of quantitative inheritance. The best lines of the HIF population for resistance to A. obtectus were the Line-45, Line-129, Line-124, Line-108 and Line-47.

Several herbivores feed on maize in field and storage setups making the development of multiple-insect resistance a critical breeding target. In this study, an association mapping panel of 341 tropical maize lines was evaluated in three field environments for resistance to FAW (fall armyworm) whilst bulked grains were subjected to MW (maize weevil) bioassay, genotyped with Diversity Array Technologies single nucleotide polymorphisms (SNPs) markers. A multi-locus genome-wide association study (GWAS) revealed 62 quantitative trait nucleotides (QTNs) associated with FAW and MW resistance traits on all 10 maize chromosomes, of which, 47 and 31 were discovered at stringent Bonferroni genome-wide significance level of 0.05 and 0.01, respectively, and located within or close to multiple-insect resistance genomic regions (MIRGRs) concerning FAW, SB, and MW. Sixteen QTNs influenced multiple-traits of which six were associated with resistance to both FAW and MW suggesting a pleiotropic genetic control. Functional prioritization of candidate genes (CGs) located within 10-30kb of the QTNs revealed 64 putative GWAS-based CGs (GbCGs) showing evidence of involvement in plant defense mechanisms. Only one GbCG was associated with each of five of the six combined-resistance QTNs, thus, reinforcing the pleiotropy hypothesis. In addition, through In-silico co-functional network inferences, an additional 107 Network-based CGs (NbCGs), biologically connected to the 64 GbCGs, differentially expressed under biotic or abiotic stress were revealed within MIRGRs. The provided multiple-insect resistance physical map should contribute to the development of combined-insect resistance in maize.

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 has been 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 gender has been evaluated both numerically and experimentally. Based on the measured results from 15 RPW collected samples with different body sizes, different RPW gender types showed unique microwave signatures. Notable shift to the sensor's resonance frequency has been achieved, where on average a resonant frequency shift of 10% for adult RPWs was achieved, while 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 development stages.

Red palm weevils (RPWs) are a major pest to coconut and palm trees, causing significant economic losses in many countries. The current control method involves using insecticides, which are unsustainable and environmentally damaging. Thus, it is necessary to develop an eco-friendly and sustainable approach to mitigate the RPW problem. Our studies have revealed that feeding RPWs with food containing specific herbs can affect the weevils' mutualistic relationship with gut microbiota or their growth hormones, resulting in a notable reduction in the metamorphosis rate at the pupation stage. For instance, the addition of Kra-jeab (a roselle Hibiscus sabdariffa) and Kra-pao (a holy basil Ocimum tenuiflorum) led to a reduction of 76.7% and 75.6%, respectively, in the metamorphosis rate, while combining the two herbs resulted in a higher reduction rate of 86.7%. In addition to these findings, altering their pupation nature by reducing the fiber length used in RPW feed to less than 1 centimeter can stop the weevil’s pupation entirely. These findings demonstrate the potential application of biological and physical factors to reduce RPWs' metamorphosis rate and control their destructive impact on palm industries, thus providing a promising solution for the conflict between palm and insect farmers.

The red palm weevil (Rhynchophorus ferrugineus) inflicts widespread damage in date palm plantations and urban settings, leading to stand loss and safety concerns, intensified by the economic and ecological burdens of synthetic preventive treatments. A novel approach emphasizes detecting weevil-infested palms through sensors and targeting control efforts at colonized trees. The study analyzes two datasets: field manager-reported results from settings with preventive pest control versus seismic sensor-monitored units. Sensor data translates into damage index values, exploring curative treatments, attack likelihood based on infestation history, and the impact of sensor-based management on infestation incidence decline. Findings reveal lower weevil infestation in urban areas and preventive-treated palm settings. A strong correlation exists between sensor indications and grower decisions in date plantations. Palms previously infested are more prone to the damage. Long-term sensor-based management significantly reduces weevil-affected palm numbers. The high infestation in sensor-equipped date palm settings stems from a gap between sensor-identified and preventively treated palms. Controlling weevils based on sensor indications aligns practically with grower curative treatments, preventing significant damage. Weevils target previously infested palms, optimizing pest control through a continuous strategy integrating sensor monitoring with prompt response treatments. This proves highly effective, offering a cost-efficient alternative to preventive treatment reliance.

The red palm weevil (RPW) Rhynchophorus ferrugineus is highly destructive invasive pest for palms whose management is mainly by application of synthetic pesticides. 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 significantly inhibits infestation signs and results in 75% and 100% protection, respectively. These results lay the foundation for investigating the protective rate of EPF products against RPW in date plantations.

RCH is known rapidly enhance cold tolerance of insects. Trehalose has been demonstrated to be one of the cryoprotectant in L. oryzophilus, an important invasive pest of rice in China. Trehalose synthesis mainly occurs through the TPS/TPP pathway in insects. In this study, LoTPS gene was cloned and characterized for the first time. Its expression and trehalose content changes elicited by RCH were investigated. Our results revealed that RCH not only increased the survival rate of adults but also upregulated the gene expression level of LoTPS and increased trehalose content under low temperature. We hypothesized upregulated LoTPS promoted trehalose synthesis and accumulation to protect adults from low-temperature damage. To further verify the function of LoTPS gene, we employed RNAi technology. Our findings showed that RCH efficiency disappeared and failed to increase the survival rate when the adults were fed dsRNA of LoTPS. Additionally, inhibiting LoTPS gene expression resulted in no significant difference in trehalose content between RCH and non-RCH treatments. Furthermore, the expression patterns of TRET and TRE were also affected. Collectively, these results indicate the critical role of LoTPS in L. oryzophilus cold resistance after RCH induction. LoTPS can enhance the survival ability by regulating trehalose metabolism. These findings contribute to further understanding of the role of TPS in insect cold resistance and invasiveness of L. oryzophilus. Moreover, RNAi of the LoTPS opens up possibilities for novel control strategies against L. oryzophilus in the future.

The implications related to the fight against alien organisms often affect different sectors, from the economic to the landscape one or from the public health to the ecological one. This paper is an upgrade of our previous study focused on the evolution of the red palm weevil in a coastal urban area (central Italy); we investigate the evolution of this parasite in the following period (2013-2020), considering both the effectiveness of the chemicals used and their potential effects. With a multidisciplinary approach, on the one hand we carried out a spatio-temporal analysis to analyze 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, and on the other hand we performed an assessment of the chemical risk associated with the substances used to protect the palms from the red weevil. The fight against weevil is now concentrated in specific areas (parks, relevant roads, villas, hotels, farmhouses, nurseries); the applied preventive chemical treatments 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 the several aspects involve into the fight against this beetle in an urban area.

The forest regeneration phase in Sweden commonly involves mechanical soil preparation followed by planting of Scots pine or Norway spruce seedlings. The prepared soil offers planting positions with different properties, including decreased damage by pine weevil (Hylobius abietis L.). Nitrogen fertilization can be applied at the time of planting to aid establishment of the seedlings. In this study we compared the effect of organic nitrogen-fertilization for different planting positions, and seedling sizes on early survival and growth of Scots pine and Norway spruce seedlings. The main planting positions were capped mound, hinge, and mineral soil. Seedlings planted close to organic material were categorized as “low quality positions”, since proximity to organic material increase pine weevil attraction. Higher mortality rates related to pine weevil damage were recorded for seedlings planted in the low-quality positions, regardless of seedling size or N-fertilization. Pine weevil attack rates increased with increasing seedling size. Growth was in general lowest in mineral soil positions. The effect of organic N-fertilization on growth was positive for spruce regardless of planting positions and seedling size, while depending on planting position and seedling size for pine, indicating that effects of organic N-fertilization depend on seedling species, -size and planting position.