Integrated Pest Management Research Articles

Exposure dose, light distribution and wavelength affect the fate of introduced bacterial biological control agents in the phyllosphere of greenhouse grown tomato

Societal Impact StatementThe use of chemical plant protection products must be reduced to promote sustainability in food production. One possible alternative is biological control agents (BCAs), but their efficacy under commercial conditions does not always reach the standard of chemical control agents. Previously, light has been found to induce mechanisms in bacterial BCAs that can affect their distribution and establishment. This could promote BCA efficacy. We looked into how monochromatic and polychromatic (which is what growers use) light treatments affected the occurrence of three BCAs post‐application. By combining two non‐chemical methods: a biological (BCA) and a cultural (light) control method, this offers a new integrated pest control strategy.Summary The dynamics and functionality of beneficial and non‐beneficial, non‐phototrophic bacteria can be influenced by light quality. We investigated if light could aid the survival of three bacterial biological control agents (BCAs; Bacillus amyloliquefaciens DSM7, Pseudomonas chlororaphis 50083 and Streptomyces griseoviridis CBS904.68) in the canopy of greenhouse‐grown tomatoes at four light treatments. Tomato plants were exposed to 50 μmol m−2 s−1 of either polychromatic light (white) or monochromatic light (blue: 420 nm, green: 530 nm and red: 660 nm) using DYNA LED lamps for a total of 48 h post foliar application of the BCAs. Leaves were harvested from two levels in the canopy at the top and middle of each plant at 0, 2, 4, 8, 12, 24 and 48 h post inoculation. The occurrences of the BCAs were quantified by plate count and droplet digital PCR (ddPCR). S. griseoviridis persisted under most treatments, whereas P. chlororaphis and B. amyloliquefaciens preferred the polychromatic and green light treatments as depicted by the viable count analyses. Significant differences between the DNA and cDNA concentrations were only noted for P. chlororaphis, with prominent wavelength effects. Light exposure dose, placement in the canopy and wavelength were found to be decisive factors for BCA re‐isolation, indicating that they have different optimal light environments.

Evaluation of TNAU Integrated pest management (IPM) module and farmers practices against maize fall army worm, Spodoptera frugiperda (J.E Smith) at Madurai in Tamil Nadu

Evaluation of TNAU Integrated pest management (IPM) module and farmers practices against maize fall army worm, Spodoptera frugiperda (J.E Smith) at Madurai in Tamil Nadu

Behavioral, Physiological, and Molecular Mechanisms Underlying the Adaptation of Helicoverpa armigera to the Fruits of a Marginal Host: Walnut (Juglans regia).

In northwest China, changes in cultivation patterns and the scarcity of preferred hosts have forced Helicoverpa armigera to feed on the marginal host walnut (Juglans regia). However, the mechanisms allowing this adaptation remain poorly understood. Here, we investigated the behavioral, physiological, and molecular mechanisms underlying the local adaptation of this pest to walnut fruits. The green husk and shell generally contained higher levels of phytochemicals than the kernel. Bioassays revealed that the phytochemical-rich green husk and shell were less preferred, reduced larval fitness and growth, and elevated the activity of detoxification enzymes compared to the nutrient-rich kernel, which were further supported by a larger number of upregulated detoxification genes in insects fed green husks or shells based on transcriptome sequencing. Together, these data suggest that P450 genes (LOC110371778) may be crucial to H. armigera adaptation to the phytochemicals of walnuts. Our findings provide significant insight into the adaptation of H. armigera to walnut, an alternative host of lower quality. Meanwhile, our study provides a theoretical basis for managing resistance to H. armigera larvae in walnut trees and is instrumental in developing comprehensive integrated pest management strategies for this pest in walnut orchards and other agricultural systems.

Insecticidal and Microbial Effect of Essential Oil on Wheat and Chickpea During Storage

In recent years, limited research works has been reported on the use of integrated pest management to control the insect and pests in stored grain. Management of stored grain insects and pests using essential oils either in combination or alone will be of great importance as it is economical and eco-friendly. Tests were conducted to evaluate the toxicological impact of essential oils on stored product beetles in wheat and chickpea storage, as well as their influence on germination characteristics. The impact of essential oils was assessed for their fumigant toxicity, mortality, repellent properties, and effects on germination against storage pests such as Sitophilus oryzae, Rhyzopertha dominica, Tribolium castaneum, and Collasobruchus chinensis in wheat and chickpea. During the fumigant toxicity test the selected essential oils either alone at 0.4 percent or in combination at 0.2 percent each were highly effective against Sitophilus oryzae, Rhyzopertha dominica, Tribolium castaneum, Collasobruchus chinensis. All the essential oils at 0.4% concentration demonstrated complete mortality within twenty-four hours of treatment against Sitophilus oryzae, Rhyzopertha dominica, Tribolium castaneum, and Collasobruchus chinensis, compared to untreated samples. The evaluated essential oils exhibit the greatest repellent activity against Sitophilus oryzae, Rhyzopertha dominica, Tribolium castaneum, Collasobruchus chinensis. Whether applied individually at a concentration of 0.4% or in combinations at 0.2%, they show no impact on the percentage of germination, vigour index, and viability significance after eight and ten months of storing wheat, respectively.

One-step TaqMan® RT-qPCR detection of sugar beet-infecting poleroviruses in Myzus persicae from yellow water pan traps opens up new possibilities for early risk assessment of virus yellows disease

Virus yellows disease (VY) is a major threat to sugar beet production in Europe. Beet chlorosis virus (BChV) and beet mild yellowing virus (BMYV) are of particular economic importance and are both persistently transmitted by the aphid vector Myzus persicae. As part of integrated pest management strategies, M. persicae influx into sugar beet fields is recorded weekly using yellow water pan traps. To date, only ELISA and RT-PCR assays have been described for BChV and BMYV detection in individual aphids.In this study, we describe for the first time two one-step TaqMan® RT-qPCR assays designed for the specific detection of BChV and BMYV in M. persicae after 7d incubation in water pan trap medium. Both viruses were reproducibly detected in individual aphids. After 7d incubation in trap medium, both viruses were reproducibly detected in individual aphids, as well as in one viruliferous aphid in a pool of 99 non-viruliferous aphids. Significant correlations can be shown between different mixing ratios of viruliferous to non-viruliferous aphids and Ct values of total RNA templates, allowing the percentage of viruliferous aphids in yellow water pan traps to be estimated using a standard curve.The described methodology provides a high sensitivity combined with a high sample throughput and can be used, after evaluation in the field, for practical monitoring, risk modelling and development of decision support systems for VY.

Effect of temperature on in vitro germination and growth of Colletotrichum fioriniae, a new emerging pathogen of olive fruits.

Olive anthracnose induced by different Colletotrichum species causes dramatic losses of fruit yield and oil quality. The increasing incidence of Colletotrichum fioriniae (Colletotrichum acutatum species complex) as causal agent of olive anthracnose in Italy, is endorsing new studies on its biology, ecology, and environmental factors such as temperature. Five isolates from different sampling sites in Lazio region (Central Italy) were studied under controlled laboratory conditions aiming to better understand the differences of thermal development among the isolates and to lay the foundations of a future mathematical model able to describe the key aspects of the pathogen's life cycle. The mycelial growth rate and the conidial germination rate were assessed at seven different constant temperatures (5, 10, 15, 20, 25, 30, and 35°C) and fixed relative humidity (100% RH). The obtained dataset was analysed to estimate the parameters of mathematical functions that connect the mycelial growth rate and the spore germination with the environmental temperature. The parameters set provided as the result of this study constitute a key step forward in the biological knowledge of the species and the basis for future formulations of mathematical models that might be the core of decision support systems in an integrated pest management framework.

SUSTAINABLE STRATEGIES FOR INTEGRATED MANAGEMENT OF BREVICORYNE BRASSICAE IN CABBAGE CULTURE: ECOLOGICAL APPROACHES AND IMPACT ON BIOLOGICAL CONTROL IN MOZAMBIQUE

Cabbage (Brassica oleracea) is a vegetable widely cultivated due to its nutritional and economic value, especially for small farmers. However, kale production faces significant challenges, mainly due to attacks by aphids (Brevicoryne brassicae), a pest that causes wilting and deformations in plants and acts as a virus vector. In regions such as Southern Africa, inadequate control of this pest has resulted in considerable losses in production, reaching 40% in Mozambique.The adult stage of Brevicoryne brassicae is the most damaging, especially affecting the cabbage crop during its vegetative phase, when the plants are most vulnerable. Effective management of this pest involves continuous monitoring and the use of Integrated Pest Management (IPM) practices, which include cultural, biological and chemical methods. Applying these techniques in an integrated way, adapted to local conditions, can significantly reduce damage and improve agricultural productivity, promoting food security and sustainability for small Mozambican farmers.

Potential distribution of Acerophagus papayae, a parasitoid of the papaya mealybug (Paracoccus marginatus), across Africa

The papaya mealybug, Paracoccus marginatus, is a highly polyphagous invasive pest that affects at least 133 economically important crops, and causes economic losses worldwide. Acerophagus papayae (Noyes and Schauff), a parasitic wasp, has proven to be a successful biocontrol agent, but its use in Africa is limited. Here, we use a predictive correlative model to explore the potential distribution of A. papayae and relate it to data showing the potential distribution of P. marginatus, to highlight potentially suitable areas for biological control of P. marginatus, for its current distribution, as well as its potential future distribution.The resulting model performed well with a test AUC of 0.89. Areas that were highly suitable for P. marginatus and were also suitable for A. papayae were highest across West Africa. Whilst there were areas which were suitable for both species in both East Africa and Central Africa, there were large areas of cropping land which were highly suitable for P. marginatus although not suitable for A. papayae. Across Northern and Southern Africa, there were limited cropping areas which were suitable for P. marginatus and where there was suitability, it was only moderate. Across these areas, there was limited suitability for A. papayae.Our results offer refined information on the potential suitability for A. papayae across Africa with the aim to help guide decisions on the areas where use of A. papayae could be used effectively as a part of an integrated pest management programme against P. marginatus.

Evaluation of Efficacy of Certain Pesticides and Black Plastic Mulch as an Approach of Developing Integrated Pest Management for Melon Fruit Fly (Bactrocera cucurbitae)

A field experiment was conducted at Pyuthan Municipality, Pyuthan district of the Federal Democratic Republic of Nepal to develop an integrated pest management strategy against melon fruit fly (Bactrocera cucurbitae). The experiment was laid out in two factorial Randomized Complete Block Design (RCBD). The first factor was different doses of pesticides; Spinosad (45% SC) @ 1ml/3l water, Cypermethrin (10% EC) @5ml/20l water and, botanical Jholmol @ 1:3 ratio (1 part Jholmol and 3 part water). The second factor was Black plastic mulch and no mulch. The pesticides were applied at 9 day intervals and data on fruit infestation, ovary damage, yield and, post-set damage were collected at 3 day intervals and the data analysed using R Studio. The result revealed highly significant differences among mulching and non-mulching plots. Mulching plots had the lowest fruit infestation (3.95%), lowest ovary damage (0.88%), lowest post-set damage (2.38%) and, higher yield per plot (21.25 kg) than non-mulched plots. Highest protection against melon fruit fly was observed by Spinosad at the third spray; percentage of fruit infestation (3.71%), ovary damage (0.76%) and yield (20.20 kg/plot) followed by Cypermethrin and Jholmol. The highest protection was obtained by the application of Cypermethrin (1.78%) at the post-set stage followed by Spinosad and Jholmol. The application of Spinosad, Cypermethrin alone with black plastic mulch provided superior protection than Jholmol and control. However, the pest reduction and yield observed on the treatments with the combination of Jholmol and black plastic mulch was satisfactory (21.87 kg/ha) than control (14.58 kg/ha). Int. J. Appl. Sci. Biotechnol. Vol 12(3): 126-136.

Chromosome-level genome assembly and annotation of Clanis bilineata tsingtauica Mell (Lepidoptera: Sphingidae).

The soybean hawkmoth Clanis bilineata tsingtauica Mell (Lepidoptera, Sphingidae; CBT), as one of the main leaf-chewing pests of soybeans, has gained popularity as an edible insect in China recently due to its high nutritional value. However, high-quality genome of CBT remains unclear, which greatly limits further research. In the present study, we assembled a high-quality chromosome-level genome of CBT using PacBio HiFi reads and Hi-C technologies for the first time. The size of the assembled genome is 477.45 Mb with a contig N50 length of 17.43 Mb. After Hi-C scaffolding, the contigs were anchored to 29 chromosomes with a mapping rate of 99.61%. Benchmarking Universal Single-Copy Orthologues (BUSCO) completeness value is 99.49%. The genome contains 252.16 Mb of repeat elements and 14,214 protein-coding genes. In addition, chromosomal synteny analysis showed that the genome of CBT has a strong synteny with that of Manduca sexta. In conclusion, this high-quality genome provides an important resource for future studies of CBT and contributes to the development of integrated pest management strategies.

Physical and chemical characterization of wild tomato Solanum habrochaites accessions for resistance to the sweetpotato whitefly

Sweetpotato whitefly Bemisia tabaci is a significant worldwide insect pest affecting tomato production, causing direct damage during feeding and transmitting multiple plant viruses to this crop. Continuing research to improve integrated pest management (IPM) of sweetpotato whitefly is required to maintain profitable tomato production for growers. This study evaluated the resistance of eight wild tomato accessions of Solanum habrochaites and four commercial tomato cultivars of Solanum lycopersicum to sweetpotato whitefly infestation. Field experiments were conducted at the Wiregrass Research and Extension Center at Auburn University, where whitefly populations were reported in vegetable crops. Accessions and cultivars were evaluated for resistance to whiteflies through the ability to reduce the insect population, analysis of the presence of glandular trichomes, and the profile and quantification of terpenes of each tomato species. Results indicated significant variations in whitefly population dynamics among the wild tomato accessions and commercial tomato cultivars. Wild tomato accessions of S. habrochaites had higher numbers of glandular trichomes and distinct terpene profiles, particularly sesquiterpenes, known for their pest-repellent properties. Multivariate analysis identified three clusters based on terpene profiles and trichome types correlating with whitefly resistance. Accessions of S. habrochaites PI127826, PI134418, and G29258 had prominent results. They significantly reduced whitefly nymph development compared to cultivars of S. lycopersicum. The GC-MS analysis of leaflet extracts revealed that accessions of S. habrochaites had higher levels of sesquiterpenes, including α-zingiberene, β-caryophyllene, and α-humulene, with PI127826 uniquely producing Ar-curcumene and 9-hydroxy-zingiberene. Results highlight the potential of wild tomato accessions of S. habrochaites in breeding programs to enhance whitefly resistance in tomatoes, which can support a sustainable IPM program.

Integrated Pest Management: An Update on the Sustainability Approach to Crop Protection.

Integrated Pest Management (IPM) emerged as a pest control framework promoting sustainable intensification of agriculture, by adopting a combined strategy to reduce reliance on chemical pesticides while improving crop productivity and ecosystem health. This critical review synthesizes the most recent advances in IPM research and practice, mostly focusing on studies published within the past five years. The Review discusses the key components of IPM, including cultural practices, biological control, genetic pest control, and targeted pesticide application, with a particular emphasis on the significant advancements made in biological control and targeted pesticide delivery systems. Recent findings highlight the growing importance of genetic control and conservation biological control, which involves the management of agricultural landscapes to promote natural enemy populations. Furthermore, the recent discovery of novel biopesticides, including microbial agents and plant-derived compounds, has expanded the arsenal of tools available for eco-friendly pest management. Substantial progress has recently also been made in the development of targeted pesticide delivery systems, such as nanoemulsions and controlled-release formulations, which can minimize the environmental impact of pesticides while maintaining their efficacy. The Review also analyzes the environmental, economic, and social dimensions of IPM adoption, showcasing its potential to promote biodiversity conservation and ensure food safety. Case studies from various agroecological contexts demonstrate the successful implementation of IPM programs, highlighting the importance of participatory approaches and effective knowledge exchange among stakeholders. The Review also identifies the main challenges and opportunities for the widespread adoption of IPM, including the need for transdisciplinary research, capacity building, and policy support. In conclusion, this critical review discusses the essential role of IPM components in achieving the sustainable intensification of agriculture, as it seeks to optimize crop production while minimizing adverse environmental impacts and enhancing the resilience of agricultural systems to global challenges such as climate change and biodiversity loss.

Effects of Microbial Biostimulants on Maize and Its Pest, the Western Corn Rootworm, Diabrotica virgifera virgifera

The western corn rootworm, Diabrotica virgifera virgifera, (Coleoptera: Chrysomelidae) is a serious pest of maize in the USA and Europe. Microbial plant biostimulants such as bacteria, fungi, and algae are designed to stimulate plant nutrition and growth, with some hypothesized to also possess insecticidal properties. We tested 10 biostimulants (four bacteria, five fungi, and one alga) under laboratory and greenhouse conditions. Most biostimulants did not affect the eggs, larvae, or adults of D.v. virgifera. However, in the laboratory, 10% of biostimulants improved egg hatching, and 40% killed some larvae, including the fungi Beauveria bassiana, Rhizophagus irregularis, and Trichoderma asperellum, and the bacterium Ensifer meliloti. Under potted-plant conditions in the greenhouse, these insecticidal effects were not detectable. However, several biostimulants slightly increased height and shoot length of uninfested maize plants, but reduced volume and length of their roots as well as above-ground biomass. Interestingly, 30% of the biostimulants enhanced the plant’s defence against larvae, for example, Bacillus amyloliquefaciens, B. subtilis, and E. meliloti. These may warrant further research into their modes of action as well as field trials to better understand and optimize their potential use in sustainable and integrated pest management.

Side effects of semi-synthetic insecticide spinetoram on the whitefly parasitoid Encarsia formosa.

Insecticide risk assessment for biological control agents is essential for implementing integrated pest management (IPM) programs. Spinetoram is a naturally derived insecticide used to control a variety of agricultural sap-sucking insect pests, and Encarsia formosa Gahan (Hymenoptera: Aphelinidae) plays a key role in the biocontrol of greenhouse whiteflies. Despite its presumed safe ecotoxicological profile, the side effects of spinetoram on E. formosa are partially unknown, especially at sublethal doses. In the laboratory, we estimated the lethal concentrations (LC) of spinetoram on E. formosa by topical exposure of pupae and 48 h residual contact exposure of emerged adults. Afterwards, we assessed the impact of spinetoram LCs on the life history traits (juvenile development, adult longevity, parasitism, adult emergence) and population growth parameter (the instantaneous rate of increase, ri) of the parasitoid. Probit analysis allowed the estimation of LC10 = 0.10 mg/L, LC50 = 0.56 mg/L, and LC90 = 3.28 mg/L. Spinetoram at LC10 had no impact on the observed parameters of E. formosa. Conversely, spinetoram at LC50 and LC90 significantly reduced adult longevity by 19.2% and 40.6%, total parasitism by 33.4% and 38.7%, and total adult emergence by 29.6% and 39.1%, respectively. Also, the ri of E. formosa was significantly affected by spinetoram LC50 and LC90 with a reduction of 8.17 and 29.83%, respectively. Our results suggested that spinetoram significantly threatens the effectiveness of E. formosa when applied at the field recommended rate. However, further validation of spinetoram under greenhouse conditions is required for a comprehensive risk assessment for E. formosa in IPM programs. © 2024 Society of Chemical Industry.

Sterol regulatory element-binding proteins mediate intrinsic fungicide tolerance and antagonism in the fungal biocontrol agent Clonostachys rosea IK726

Sterol regulatory element-binding proteins (SREBPs) are transcription factors governing various biological processes in fungi, including virulence and fungicide tolerance, by regulating ergosterol biosynthesis and homeostasis. While studied in model fungal species, their role in fungal species used for biocontrol remains elusive. This study delves into the biological and regulatory function of SREBPs in the fungal biocontrol agent (BCA) Clonostachys rosea IK726, with a specific focus on fungicide tolerance and antagonism. Clonostachys rosea genome contains two SREBP coding genes (sre1 and sre2) with distinct characteristics. Deletion of sre1 resulted in mutant strains with pleiotropic phenotypes, including reduced C. rosea growth on medium supplemented with prothioconazole and boscalid fungicides, hypoxia mimicking agent CoCl2 and cell wall stressor SDS, and altered antagonistic abilities against Botrytis cinerea and Rhizoctonia solani. However, Δsre2 strains showed no significant effect. Consistent with the gene deletion results, overexpression of sre1 in Saccharomyces cerevisiae enhanced tolerance to prothioconazole. The functional differentiation between SRE1 and SRE2 was elucidated by the yeast-two-hybridization assay, which showed an interaction between SREBP cleavage-activating protein (SCAP) and SRE1 but not between SRE2 and SCAP. Transcriptome analysis of the Δsre1 strain unveiled SRE1-mediated expression regulation of genes involved in lipid metabolism, respiration, and xenobiotic tolerance. Notably, genes coding for antimicrobial compounds chitinases and polyketide synthases were downregulated, aligning with the altered antagonism phenotype. This study uncovers the role of SREBPs in fungal BCAs, providing insights for C. rosea IK726 application into integrated pest management strategies.

Life table analysis and RNA-Seq reveal hormesis and transgenerational effects of deltamethrin on Aphis gossypii.

Deltamethrin, as a highly effective and broad-spectrum insecticide, has been widely used for agricultural pest control such as Aphis gossypii worldwide. Increasing evidence has shown that despite great economic benefits brought by it, deltamethrin has also non-negligible side effects. However, the potential risks and related molecular mechanisms remain largely unclear. Herein, the life table parameters and transcriptome sequencing analyses of the four successive aphid generations were performed to investigate the hormesis and transgenerational effects of deltamethrin on A. gossypii. The life table analysis showed that although the exposure of G0 aphid to 30% lethal concentration (LC30) deltamethrin significantly reduced the net reproduction rate (R0), intrinsic rate of increase (r), and fecundity of G0, but it significantly enhanced the R0 and fecundity of subsequent two generations (G1 and G2) of A. gossypii. Moreover, transcriptomic analyses showed that the signaling pathways related to posttranscriptional regulation (spliceosome), protein processing, longevity regulating, and cell proliferation (DNA replication, homologous recombination and non-homologous end-joining) were significantly up-regulated in G1 or G2 under LC30 deltamethrin treatment. Additionally, we also found that the deltamethrin-sulfoxaflor rotation of G0 and G1 still induced reproductive stimulation, but the reproductive stimulation induced by insecticides rotation treatment was significantly lower than that in the deltamethrin exposure alone. Our study demonstrates that sublethal concentrations of deltamethrin significantly enhanced the offspring fecundity of cotton aphid. In addition, our study also reveals the transcriptional response mechanism of hormesis-induced fecundity increase, providing valuable reference for optimizing the application of deltamethrin in integrated pest management. © 2024 Society of Chemical Industry.

Enhancing yield and economic benefits through sustainable pest management in Okra cultivation.

Okra (Abelmoschus esculentus) is a prominent vegetable crop in Asia, confronting persistent threats from pests such as leafhoppers, whiteflies, and shoot and fruit borers. Conventional chemical control methods, despite their adverse ecological effects, remain the primary approach for pest management. Indiscriminate chemical use has led to reduced biodiversity among natural predators and the disruption of food webs in ecosystems. To address these challenges, this study assessed the efficacy of integrated (IM) and biointensive (BM) pest management modules in comparison to conventional chemical methods (CM) for mitigating insect damage to okra leaves and fruits, and subsequently, their impact on okra yield. Our result revealed that the BM exhibited the least effectiveness but outperformed untreated control plots significantly. In contrast, both IM and CM significantly reduced damage from sap-sucking insects and borer pests. Notably, plots treated with the chemical module found decreased populations of natural enemies. The IM demonstrated the lowest fruit infestation rate (5.06%), yielding the highest crop production (8.97 t ha-1), along with the maximum net return (Indian Rupees: 44,245) and incremental cost-benefit ratio (3.31). Thus, the study suggested that the implementation of integrated pest management practices can result in higher okra yields and greater economic benefits. These findings shed light on the potential of sustainable agricultural practices as a safer and more economically viable alternative to chemical-intensive pest control in okra cultivation.

Can Pest Management and Cultivar Affect Phytoptus avellanae Infestations on Hazelnut?

The big bud mite Phytoptus avellanae is a resurgent pest of hazelnut, Corylus avellana, causing substantial yields reductions in many productive areas. Mites colonise and develop within healthy buds which become swollen, with subsequent alteration to the plant's development. To date, there has been limited knowledge on how the cultivar and pest management strategies affect infestations. This study explored these aspects through two ad hoc experiments carried out in central Italy. In the first experiment, the susceptibility of 11 cultivars with different geographic origins was tested in a germplasm hazelnut collection. The second experiment assessed the infestation level in orchards with integrated pest management (IPM) and organic pest management strategies and in a renaturalised environment (a former agricultural area now converted in a natural park). The results showed that the most and the least susceptible cultivars were Tonda Gentile and Nocchione, respectively. No significant differences were found between IPM and organic management, but they were both different to the renaturalised environment. The outcomes of this research can serve as a valuable reference and can be applied to all current or potential hazelnut cultivation areas characterised by the same environmental conditions.

Leveraging long-lasting insecticide-incorporated netting to improve fumigation efficacy against stored product insects.

Long-lasting insecticide-incorporated netting (LLIN) has successfully been used to impair mobility and prevent infestation of stored grain by stored product beetles. Understanding how to integrate LLIN with existing integrated pest management (IPM) tactics, such as phosphine fumigation, can further enhance IPM programs. We used three 110 metric tons (MT) capacity grain bins, and in each, 60 perforated buckets (e.g., miniature silos) were filled with 500 g of uninfested wheat. Miniature silos were protected by LLIN (0.3% α-cypermethrin, Carifend®, BASF), positive control (without insecticide), or negative control (no netting). Half of each treatment was randomly assigned to phosphine fumigation treatment, while the remainder were not fumigated. Monthly samples of 100 g of grain from four silos from each treatment in four blocks from three-grain bins were taken between June and October both in 2022 and 2023. We determined whether phosphine fumigation could be reduced with the use of LLIN over the season. Overall, we found that silos protected with LLIN showed insect dispersal and progeny production that was reduced by 83-99% and 89-99%, respectively, compared with insecticide-free netting and no-netting controls. Additionally, damage in silos was reduced by 37-99% compared with controls. Importantly, the total number of fumigations could be reduced by 68-91% by using LLIN compared with controls. Our study demonstrates that LLIN is consistently effective for existing pest management tactics such as phosphine fumigation in bulk storage structures. © 2024 Society of Chemical Industry. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Constitutive and inducible tomato defenses contribute to Bacillus thuringiensis lethality against Spodoptera exigua

In nature, insect herbivory exerts continuous selective pressure on plants that, in turn, have developed a wide array of constitutive and inducible defenses to fight against attackers. Since plant defenses may affect higher trophic levels, including entomopathogens, further research is required to understand how plant compounds influence insect-pathogens interactions and their implications for integrated pest management programs. Here, we evaluated the impact of tomato defenses on the lethality produced by the bacterial entomopathogen Bacillus thuringiensis (Bt) against second instar larvae of Spodoptera exigua. We first examined the effect of constitutive defenses from fifteen wild tomato species and forty cultivated varieties (Solanum lycopersicum) on S. exigua larval growth and susceptibility to Bt. The results showed larvae fed on wild tomato species had a reduced larval growth compared to larvae fed on cultivated varieties, whereas susceptibility to Bt was similar between both groups. We then selected six cultivated varieties, including those with high and low impacts on larval growth and Bt-induced mortality, to further explore the effect of inducible defenses. Elicitation of defenses by methyl jasmonate (MeJA) reduced larval growth and increased basal mortality. Additionally, when larvae were infected with Bt, MeJA treatment further increased their susceptibility to the entomopathogen. Metabolomic analysis confirmed a reprogramming of tomato leaf metabolism following MeJA elicitation, with an induced accumulation of bioactive compounds, such as saponins or flavonoids, known for their anti-herbivory properties in most tomato varieties. Overall, these data reveal that both constitutive and inducible tomato defenses not only protect the plant by directly affecting the insect pest but also enhance the efficacy of bacterial entomopathogens