Incipient resistance of the African maize stemborer, Busseola fusca (Lepidoptera: Noctuidae) to Cry2Ab2 maize in South Africa
Resistance of Busseola fusca (Lepidoptera: Noctuidae) to Cry1Ab was documented in 2006, 7 years after the first cultivation of MON 810 in South Africa. This was mitigated by introducing a second-generation Bacillus thuringiensis (Bt) maize (MON 89034), which contains the Cry1A.105 and Cry2Ab2 proteins. The first reports of B. fusca infestations of MON 89034 maize came in the KwaZulu-Natal province (2017-2018 cropping season), followed by reports in the Mpumalanga province (2022-2023 season). Here we report results of artificial diet- and plant-based laboratory assays to assess the susceptibility of B. fusca populations to the Bt proteins in MON 89034.
Evaluation of the strategy for insecticidal crystal encapsulation with cell wall in industrial processes
Bacillus thuringiensis (Bt) can produce insecticidal crystal proteins during sporulation, and these are the basis of the most successful microbial insecticides in use today. However, the susceptibility of insecticidal crystal proteins to inactivation by ultraviolet (UV) radiation from sunlight causes damage to the insecticidal crystals and subsequent loss of toxicity. The deletion of the mclX gene, an unknown functional gene, can make the insecticidal crystal proteins become encapsulated by the cell wall which provides some protection against UV radiation. This study evaluates the potential of this innovative strategy during the industrial process of commercial strain KN11.
Determining the optimal time window to detect emerald ash borer damage for effective management
The emerald ash borer (EAB) is an invasive pest of global concern. Accurate detection of EAB is crucial for effective management. Traditional field surveys fail to meet large-scale monitoring requirements. Remote sensing methods offer a potential solution, but the phenological decline of ash trees may obscure the remote sensing features for detecting EAB. Therefore, determining the timing of leaf abscission caused by EAB before phenology is crucial for effective detection. We collected time-series data of Leaf Area Index (LAI), leaf sizes, and hyperspectral images of damaged ash trees throughout the growing season to determine the optimal detecting time window for EAB detection using field surveys or remote sensing techniques.
Salivary effector DcE1 suppresses plant defense and facilitates the successful feeding of Asian citrus psyllid, Diaphorina citri
Piercing-sucking insects secrete diverse repertoires of effectors into their hosts to weaken host defenses and promote infestation. The Asian citrus psyllid, Diaphorina citri Kuwayama, is the most destructive insect pest in citrus orchards because of its role as a vector for the huanglongbing pathogen, Candidatus Liberibacter asiaticus (CLas). However, specific effector proteins and their functions in D. citri remain unclear.
What motivates the choice to custom hire pest management spraying services?
This article presents a model of how farmers choose to custom hire for pest control. The decision-making process is illustrated through a discrete choice experiment conducted via a pilot survey of soybean growers in Michigan, Illinois, and Indiana. Farmers responded to a hypothetical pest infestation by choosing between custom operators, spraying on their own, or leaving the field to its fate.
Bee bread collected by honey bees (Apis mellifera) as a terrestrial pesticide biomarker to complement water studies
Pesticides in aquatic environments are frequently studied, yet those in terrestrial environments remain relatively unexplored. This study monitored bee bread collected from two apiaries located in a typical agricultural environment in Switzerland from March to August 2022 as a proxy for terrestrial pesticide inputs. The temporal appearance of the selected pesticides was compared to their profiles in the water of a small catchment within this area.
RNAi-based transgenic maize to control double-spotted leaf beetle (Monolepta hieroglyphica)
The double-spotted leaf beetle (DLB), Monolepta hieroglyphica, is becoming a significant corn pest in China. It mainly attacks corn silk and developing kernels during the adult stage and is causing significant corn yield loss in north-eastern China. The damage caused by DLB is expected to worsen as pesticide usage is likely to decrease along with the upcoming commercial planting of transgenic lepidopteran-resistant maize in China. Therefore, it is highly desirable to develop transgenic corn for DLB resistance.
Efficacy and utility of isocycloseram a novel isoxazoline insecticide against urban pests and public health disease vectors
Isoxazolines inhibit γ-aminobutyric acid chloride channels in insects and acarids by binding to postsynaptic receptors. This prevents chloride influx, leading to depolarization/hyperexcitation, paralysis, and death. Here, we evaluated the potential utility of a novel isoxazoline, isocycloseram, against several urban insect pests.
Linalool fumigation improves mating competitiveness of males for population suppression of the global fruit pest Cydia pomonella
The implementation of sterile insect technique (SIT) has proven effective in the area-wide suppression of several significant agricultural and sanitary pests by using traditional cobalt-60 (Co-γ) as a radiation source. Recently, X-ray has been validated as a feasible alternative to Co-γ radiation sources. Nonetheless, higher doses of X-ray irradiation led to insect sterility but diminish mating competitiveness, thereby impacting the effectiveness of SIT applications.
RNA interference-mediated targeting of monooxygenase SsMNO1 for controlling Sclerotinia stem rot caused by Sclerotinia sclerotiorum
Sclerotinia sclerotiorum is a devastating fungal pathogen that poses a threat to a variety of economically important crops. Owing to the lack of highly resistant cultivars and the prolonged survival of sclerotia, effective control of Sclerotinia diseases remains challenging. RNA interference (RNAi) agents targeting essential active transcripts of genes associated with the development and virulence of pathogens are a valuable and promising disease control method.
Reduction of pesticide dosage and off-target drift with enhanced control efficacy in unmanned aerial vehicle-based application using lecithin adjuvants
Unmanned aerial vehicles (UAVs) are increasingly used in precision agriculture, particularly for pesticide application in rice cultivation. One challenge is off-target pesticide drift, which raises environmental concerns and reduces pesticide efficiency. Lecithin adjuvants have been suggested to enhance droplet stability, reduce drift, and improve control efficacy. This study aims to evaluate the efficiency of lecithin adjuvants in reducing pesticide drift and improving deposition during UAV-based pesticide application under various paddy field conditions.
The evaluation on control potential using X-ray to irradiate adult Spodoptera frugiperda (Lepidoptera: Noctuidae)
The sterile insect technique (SIT), involving the rearing of larvae for pupation followed by irradiating pupae, is employed for environmentally friendly invasive pest management. Despite its effectiveness, the cost of pupae production poses challenges for small farmers in developing countries. Alternatively, utilizing insect trapping techniques can capture abundant adult insects in their natural habitats, but application potential of adult SIT approach remains unclear.
Enhancing collaboration quotient in crop protection research and development - multi-disciplinary cross-learning to promote sustainability
After a decade of consolidation with a focus on top market players, global crop protection research is undergoing a paradigm transition by integrating new cutting-edge technologies originating from established and new research organizations. Both development and distribution organizations are working together to make these innovations available to the global farming community. For this, excellent crop protection products are in demand, creating value for farmers and society with superior biological performance and at the same time very high product safety profiles. However, the enormous constraints researchers are exposed to, require the discovery and development of innovative solutions in the shortest possible time frame, while embracing environmental, social, and governance (ESG) objectives as the new normal across the whole industry. Today, fully integrated research and development (R&D) companies are addressing the whole plethora of agrochemistry, biologicals and plant health products, organic farming, seeds and traits, new application technologies, digital farming, improved diagnostics, artificial intelligence (AI), and machine learning (ML)-based approaches. However, there is still a strong need for further innovations from a wide range of sources. Targeted collaboration across various market players is key to combining required activities. This mandates a high level of discipline to frame the proprietary and knowledge environment across the industry. Furthermore, the cooperation of industry and academia will enable an extra push for innovation in the crop protection landscape. Current trends and suggestions are given of how collaborations need to be framed within the industry as well as within the public sector. © 2024 Society of Chemical Industry.
Evaluating the use of in-season measures of pest abundance to predict end-of-season damage: a study in commercial almond (Prunus dulcis)
Pre-harvest pest management tools are essential to minimizing crop loss. The development of predictive models using early warning signs of pest abundance to predict imminent crop loss can guide management decisions and enable targeted, well-calibrated intervention. With sufficient data, in-season measures of pest abundance can be an important factor in generating accurate predictions of damage. However, sampling plans for tracking insect phenology and those designed to guide informed pest-management may not be equivalent. Using data from a commercial almond orchard setting, we evaluated five different lure-trap combinations used for monitoring navel orangeworm (Amyelois transitella; a primary pest of almond) under different management conditions. Using these data, we developed a predictive model of almond damage and evaluated the contribution of in-season measures of pest abundance towards accurate predictions of end-of-season damage.
Psyllid-mite interactions promote psyllid fecundity by selecting for a different life history
In interspecific competitive interactions at the same trophic level, herbivores are often hypothesized to exhibit a fast life-history strategy characterized by early reproduction and a short lifespan. Here, we analyzed the shift in life history of the psyllid Bactericera gobica when it interacts with the aphid Aphis gossypii, the thrips Frankliniella occidentalis, or the mite Aceria pallida in similar ecological niches because all of them cause damage to goji berry leaves.
Combination of atmospheric and room temperature plasma and ribosome engineering techniques to enhance the antifungal activity of Bacillus megaterium L2 against Sclerotium rolfsii
Sclerotium rolfsii is an extremely destructive phytopathogenic fungus that causes significant economic losses. Biocontrol strategies utilizing antagonistic microorganisms present a promising alternative for controlling plant pathogens. Bacillus megaterium L2 has been identified as a potential microbial biocontrol agent in our previous study; however, its efficacy in controlling pathogens has yet to meet current demands. This study aims to enhance the antifungal activity of strain L2 against S. rolfsii R-67 through a two-round mutagenesis strategy and to preliminarily investigate the mutagenesis mechanism of the high antifungal activity mutant.
Cry1 resistance in a CRISPR/Cas9-mediated HaCad1 gene knockout strain of the Australian cotton bollworm Helicoverpa armigera conferta (Lepidoptera: Noctuidae)
Helicoverpa armigera is a highly polyphagous species that causes huge losses to agricultural and horticultural crops worldwide. In the cotton industry, H. armigera, including the Australian subspecies Helicoverpa armigera conferta, is largely managed using genetically modified crops that express insecticidal toxins, such as Cry1Ac. Resistance to Cry1 proteins occurs and, in some cases, is mediated by changes to HaCad1, a gene that encodes the midgut protein cadherin. Around the world, numerous resistance-associated polymorphisms have been identified in the HaCad1 gene of H. armigera, but Cry1Ac resistance is rare in the Australian subspecies. We used CRISPR/Cas9 to disrupt the cadherin gene in H. armigera conferta and characterised the resulting phenotype with bioassays and transcriptomics.
Response of the tomato leaf miner Phthorimaea absoluta to wild and domesticated tomato genotypes
Phthorimaea absoluta, a highly destructive invasive pest, poses a significant threat to tomato production globally. Exploring alternative control methods, such as host plant resistance can contribute to diminish reliance on insecticides and promote sustainable integrated pest management (IPM) practices. Thus, the identification of new P. absoluta-resistant tomato cultivars and potential wild sources for breeding programmes remains imperative. We evaluated the effect of 19 tomato genotypes, comprising 16 domesticated varieties and three wild tomato species, on oviposition output of female P. absoluta, as well as on larval performance under no-choice conditions using detached leaves. We also characterized and quantified glandular and nonglandular trichomes, exploring their potential correlation with the response of P. absoluta to the tomato plants.
Effect of intercropping apple trees with basil (Ocimum basilicum) or French marigold (Tagetes patula) on the rosy apple aphid regulation (Dysaphis plantaginea) and the abundance of its natural enemies
In a global context of pesticide reduction, the sustainable management of aphids is a major challenge in maintaining economically viable fruit production. Intercropping with companion plants (CPs) that emit volatile organic compounds (VOCs) with repellent or attractive properties could be successful in the laboratory. Still, their effects on the orchard have been little documented. We tested in 2018 and 2019 the hypotheses that the introduction of basil or French marigold, decreases the populations of Dysaphis plantaginea Passerini, the rosy apple aphid (RAA) and increases the abundance of its natural enemies (NEs) in an apple orchard in the south of France.
Enhancing agrochemical delivery in citrus leaves with geraniol: a promising strategy for controlling huanglongbing (HLB)
Citrus huanglongbing (HLB) is a devastating disease in citrus, caused by Candidatus Liberibacter asiaticus (CLas), which primarily resides in the phloem where chemicals cannot effectively reach, posing a significant challenge in controlling HLB. To address these challenges, plant essential oils (EOs), widely used as transdermal enhancers and known for their benefits for plant tissues, were investigated for their potential to enhance chemical permeation.
Natural UV protectants and humectants to improve the efficiency of Steinernema carpocapsae in controlling foliar pests
Entomopathogenic nematodes (EPNs) are recognized as effective biocontrol agents against various soil-dwelling pests. However, their efficacy in managing leaf pests is often constrained by factors such as ultraviolet (UV) radiation and desiccation.