The brown stink bug, Euschistus heros, is a major pest of soybean (Glycine max) in Brazil, and the development of alternative control strategies is urgently needed. This study evaluated the biocontrol potential of two native endophytic fungal isolates, Trichoderma asperelloides SF001 and Beauveria bassiana SF002, against E. heros under controlled experimental conditions. Both strains caused significant adult mortality, with control efficacies of 58% (SF001) and 46% (SF002). Chitinase assays and UHPLC-Q-TOF metabolomic profiling revealed distinct biochemical characteristics between the two strains: SF002 exhibited higher chitinolytic activity, whereas SF001 produced a diverse array of peptaibols, including asperelines; SF002, in turn, synthesized bioactive cyclic peptides. When co-applied to soybean plants, the SF001 + SF002 combination significantly increased peroxidase, polyphenol oxidase, and phenylalanine ammonia-lyase activities compared with individual applications, with effects persisting for up to 15 days after treatment. These findings suggest that the combined use of T. asperelloides SF001 and B. bassiana SF002 may contribute both to direct insect suppression and to the modulation of plant defense-related responses, highlighting their potential as a dual-strategy approach for integrated management of E. heros in soybean production systems.
Imidazolinone tolerant crop varieties are being developed to deal with problem weeds including brome grass (Bromus diandrus and B. rigidus), annual ryegrass (Lolium rigidum), and barley grass (Hordeum spp.). Despite anecdotal farmer reports of imidazolinone herbicide induced crop injury, determining the phytotoxicity thresholds of imazamox and imazapyr soilborne residues for susceptible lines of cereal and legumes as subsequent crops has not been conducted. Eight field experiments were conducted across two contrasting Australian grain cropping regions, in two growing seasons to investigate the impact of soilborne Intervix (R) (imazamox and imazapyr) herbicide residues on crop growth and productivity of tolerant and susceptible wheat and lentil genotypes. Four pot experiments were conducted to model phytotoxicity thresholds of susceptible wheat and lentil genotypes. Phytotoxicity thresholds for the effective dose of Intervix (R) necessary to achieve a 20% reduction in shoot biomass (ED20) indicated that lentils at 0.41 mu g kg- 1, were more sensitive than wheat which had an ED20 of 2.52 mu g kg- 1. Field data for the two sites indicated that soilborne residues persist in Australian grain cropping systems at levels sufficiently high (3.6 - 3.9 mu g kg- 1) to cause a 20% reduction in shoot and root biomass for susceptible wheat and lentil genotypes following imazamox and imazapyr application at the recommended field application rate. The phytotoxicity thresholds generated from this research provide a practical foundation for developing predictive tools that link measured soil residues with crop safety thresholds. Incorporating such thresholds into decision-support systems would assist growers in evaluating rotational risks more accurately, especially when environmental conditions slow herbicide breakdown.
In response to increasing pressure to reduce reliance on synthetic chemical pesticides, biological control and biostimulant products are being promoted as potential alternatives for more sustainable crop management. However, adoption of these products remains limited, particularly in Ireland, where no specific studies have investigated farmers' reasons for adopting or not adopting these products. To begin to address this knowledge gap, this study surveyed 94 Irish tillage farmers (representing a production area up to 13,000 ha) with an online questionnaire, to examine current perceptions, levels of adoption, and obstacles to wider use of biocontrol and biostimulant products. Overall, 65% of farmers reported using at least one such product, and 81% considered them useful in cropping systems, reflecting a perceived value. The most frequently cited barriers were lack of knowledge (38%) and absence of region-specific performance data (29%). To support realistic policy targets aligned with the European Union's Farm to Fork Strategy, extensive local investigations are now needed to provide farmers with reliable, objective data on product effectiveness within Irish conditions. The study also highlights effective pathways for knowledge transfer, including leveraging advisors, specialist farming groups, and peer networks. By addressing information gaps and strengthening knowledge exchange - if products become available and are proven effective in specific crops and climatic regions then these findings offer guidance for integrating biocontrol and biostimulant solutions into integrated pest management systems and advancing more sustainable, reduced-pesticide farming practices.
Stemona japonica is a medicinal herb widely cultivated in Guizhou Province, China, due to its significant economic value. In September 2025, a previously unreported leaf spot disease was observed on S. japonica in Huangping County, Guizhou, causing severe yield losses. These lesions gradually expanded to cover entire leaves, ultimately causing leaf wilting and plant death and resulting in reduced yields. In this study, the disease was investigated using a five-point sampling method. Infected leaves were collected and subjected to tissue isolation under laboratory conditions. Based on pathogenicity tests, morphological characteristics, and phylogenetic analyses of ITS, TEF1-alpha, and TUB2 sequences, the causal agent was identified as Nigrospora sphaerica. This study is the first to report Nigrospora sphaerica as the causal agent of leaf spot disease in Stemona japonica. This finding significantly contributes to our understanding of pathogen diversity in this valuable medicinal plant and provides an essential theoretical basis for disease diagnosis, future management, and targeted control strategies.
The Asian citrus psyllid (Diaphorina citri), the insect vector of Candidatus Liberibacter asiaticus, is responsible for spreading huanglongbing (HLB), the most devastating citrus disease worldwide. RNA interference (RNAi) has emerged as a promising, species-specific, and environmentally friendly strategy for managing D. citri populations. However, the success of RNAi-based control depends on selecting effective gene targets and efficient dsRNA delivery methods. Four candidate genes involved in core physiological processes were screened via oral ingestion of dsRNA in sucrose solution. Two genes, ATP synthase beta and Actin-alpha, were chosen for further evaluation based on their strong gene-silencing responses. RNAi efficiency and biological effects were assessed through both oral delivery and microinjection. Gene expression was quantified by RT-qPCR, and mortality, oviposition, and sexspecific differences were evaluated on these target genes. Oral delivery of dsRNA targeting ATP synthase beta and Actin-alpha significantly increased adult mortality (up to 74.8%) and reduced oviposition by 61.8%, highlighting their potential as a practical, field-deployable RNAi strategy. Notably, Actin-alpha expression was higher in females than in males, correlating with sex-specific differences in RNAi efficiency and reproductive output. This study identifies ATP synthase beta and Actin-alpha as promising RNAi targets for controlling D. citri and demonstrates the potential of oral dsRNA delivery as a scalable, environmentally safe strategy to reduce psyllid populations and mitigate HLB transmission in citrus crops.
Eucommia ulmoides is an economically and medicinally important tree species indigenous to China. It is widely cultivated across 27 provinces and municipalities, with a total planting area of approximately 333,500 ha and an annual output value exceeding 7 billion USD. In April 2024, a severe leaf spot disease with an incidence of 20-35% was observed in an E. ulmoides plantation at Guizhou University. Symptoms appeared as irregular brown-black spots with distinct dark brown borders and surrounding chlorosis. To identify the pathogen, we isolated the fungus from diseased tissue and performed morphological and multilocus phylogenetic analyses (ITS, TEF, Alt a 1, RPB2, H3), identifying it as Alternaria tenuissima. Pathogenicity test was confirmed by inoculating E. ulmoides cultivars under greenhouse conditions. To our knowledge, this is the first report of A. tenuissima causing leaf spot disease on E. ulmoides in China. This study provides essential information for the accurate diagnosis and management of this disease, supporting the sustainable cultivation of E. ulmoides.
Blossom blight of almond, caused by Monilinia laxa, mainly affects flowers and early-stage fruits. In Spain, the intensification and modernization of almond production have contributed to increasing disease incidence. The number of authorized products available to control this disease is limited, and their efficacy under field conditions is often suboptimal. In this study, we evaluated different products against M. laxa through in vitro, in vivo, and under field conditions. First, the efficacy of 25 products was tested in vitro against M. laxa inoculum at three doses (commercial dose, +/- 10-fold). The most effective products were further tested in vivo using almond detached-flowers from cvs. 'Soleta' and 'Tardona', assessing the disease incidence and severity. The best 10 products were also tested on 'Soleta' under field conditions, over two consecutive years. Our results showed that in both studies, in vitro and in vivo, difenoconazole was consistent with >90% disease reduction compared to the control. Field trials revealed that seven products significantly reduced the blossom blight incidence: difenoconazole, tebuconazole, cyprodinil, cyprodinil + fludioxonil, fluxapyroxad + pyraclostrobin, boscalid + pyraclostrobin, and kresoxim-methyl + difenoconazole. These results indicated that none of the active ingredients (AIs) tested consistently provided complete disease control across all assays. Nevertheless, in this study, a range of products with moderate to high efficacy were identified offering potential for integration into a comprehensive and sustainable disease management strategy.
Greenhouse tomato crops often have tall plant architecture and obvious canopy stratification, which lead to insufficient spray deposition on middle and lower leaves. To address this problem, a vertical three-zone counter-spraying device was developed. A three-factor quadratic regression orthogonal rotation design was conducted to evaluate the effects of nozzle spacing, nozzle inclination angle, and nozzle-to-plant distance on droplet deposition. Regression models and response surfaces were then established. Results showed that (1) all three factors significantly affected spray coverage on both adaxial and abaxial leaf surfaces; (2) the optimal parameters were 43cm nozzle spacing, 20 degrees inclination, and 21 cm spray distance, resulting in predicted coverage rates of 76.92% and 32.56%. Finally, the field experiment showed that the average coverage rate of leaf surface reached 80.51 %, the average coverage rate of leaf back reached 36.84 %, and the coefficient of variation was less than 5 %; and (3) Compared with the traditional horizontal spraying method, the leaf back coverage increased by about 9 %. At the same time, compared with the artificial backpack sprayer, the pesticide consumption was reduced by about 45.5 %. These results suggest that the model has a certain explanatory value for spraying performance and may provide a useful reference for improving spray distribution and promoting intelligent spraying technology in protected cultivation.
Insect symbionts play an important role in the host's resistance to insecticides, but how their community shapes host resistance in field populations remains mostly elusive. In this study, we focused on the correlations between the symbiotic bacterial community, resistance levels, and detoxifying enzyme activities in the field populations of a major rice pest, Chilo suppressalis. The resistance levels and detoxifying enzyme activities among the eight populations of C. suppressalis to five insecticides during 2023-2024 showed significant variations. After performing high-throughput sequencing of their bacterial community, we found that the overall characteristics of the symbiotic bacterial community showed little correlation with resistance, but the abundance of some core bacteria was significantly correlated with resistance. Wolbachia and Latiplantibacillus both showed positive correlations with resistance to four types of insecticides. These findings provide important references for future studies investigating the relationship between bacterial communities and insecticide resistance.
Alternaria leaf blight (ALB), caused by Alternaria spp., is a major disease of carrot (Daucus carota) that can lead to significant yield loss by destroying foliage required for mechanical harvesting. While fungicides are the primary management tool, the comparative efficacy of different methods, such as tractor-mounted sprayer application versus solid-set overhead sprinkler application, is not well understood. This study evaluated the performance of three conventional and three OMRI-listed fungicides delivered by both methods over two years (2023-2024) in North Florida. Disease was assessed using the area under the disease progress curve (AUDPC), and data were analyzed using a two-way ANOVA on ranks. In Year 1 (2023), under lower disease pressure, Fungicide, Application Method, and their Interaction significantly affected ALB control (P < 0.001). Tractor-mounted sprayer application was significantly more effective than solid-set overhead sprinkler application for Fontelis (P = 0.0390) and Nordox 75WG (P = 0.0137). In Year 2 (2024), under higher disease pressure, only the Fungicide effect was significant (P < 0.001). Conventional fungicides (Miravis Prime, Merivon, Fontelis) provided excellent control and were statistically superior to all OMRI-listed options, which grouped with the untreated control. Although the Interaction was not significant in 2024, the tractor-mounted sprayer application of Fontelis remained more effective than solid-set overhead sprinkler application (P = 0.0153). These results indicate that effective ALB management relies heavily on fungicide selection, particularly under high disease pressure, though tractor-mounted application remains advantageous for enhancing the performance of specific chemistries like Fontelis.
Maruca vitrata Fab. (Lepidoptera: Crambidae), is the most devastating insect pest of pigeonpea under tropical and subtropical regions of the world. In this study, the effects of interspecific derivatives of pigeonpea were assessed on the growth, development and feeding performances in M. vitrata under laboratory conditions. The developmental and physiological parameters of M. vitrata were linked with the phytochemicals in the flowers and pods of these interspecific derivatives. The results revealed that M. vitrata had the shortest development period when fed on susceptible genotype (MN 1) and the longest development period on the interspecific derivatives. The approximate digestibility (AD), efficiency of conversion of ingested food into body matter (ECI), efficiency of conversion of digested food into body matter (ECD), relative growth rate (RGR), relative consumption rate (RCR) were highest on susceptible genotype (MN 1) and lowest on interspecific derivatives (ENT 21-154-11 and ENT 21-1389), respectively. The biochemical analysis of the interspecific derivatives exhibited elevated levels of tannins, whereas the susceptible genotype showed higher amount of total soluble sugars, reducing sugars, proteins and amino acids. The defensive components in the interspecific derivatives impaired the growth indices and nutritional requirements of M. vitrata, resulting in delayed larval development and reduced feeding efficiency as compared to the susceptible genotype. These findings highlight the promising potential of interspecific derivative-based pest suppressive breeding strategies within the integrated pest management (IPM) framework.
Lithocarpus litseifolius (Sweet Tea) is a valuable medicinal and edible plant widely used in pharmaceuticals, functional tea beverages, and the production of natural sweeteners. In August 2023, anthracnose emerged as a destructive disease in L. litseifolius cultivation areas of Yiyang County, Jiangxi Province, China, causing substantial quality and yield losses and threatening safe production. Typical symptoms began as small, light-brown, nearly circular leaf spots that subsequently expanded into circular, oval, or irregular necrotic lesions ranging from grayish white to grayish brown, consistently surrounded by a distinct yellowish chlorotic halo. Based on integrated evidence from morphological characteristics, multi-locus phylogenetic analyses (ITS, GAPDH, ACT, HIS3, TUB2, CAL, and CHS), and pathogenicity assays, the pathogen was identified as Colletotrichum aotearoa. To our knowledge, this is the first report of C. aotearoa causing anthracnose on L. litseifolius. These findings provide critical pathogen information and a scientific basis for the precise control of L. litseifolius anthracnose, which is of great practical importance for ensuring high-quality and safe production of this crop.
The invasive spotted-wing drosophila Drosophila suzukii has led to intensified insecticide use in soft-skinned fruit production, highlighting the need for alternative management strategies. Plant-based approaches, including trap cropping, have already been explored. However, field evidence for effective "dead-end" plants (species that elicit oviposition without successful offspring development) remains limited. In this study, we evaluated candidate ornamental species for their potential to function as demographic sinks under realistic conditions. We quantified both oviposition intensity and subsequent adult emergence to identify plant species where high oviposition intensity coincided with limited adult emergence. Field data revealed substantial variation in fruit acceptance and oviposition intensity among species. Several candidates, including Phytolacca acinosa and Prunus lusitanica received substantial oviposition but showed no successful adult emergence, indicating strong developmental constraints. However, overall oviposition levels on the selected species were low, limiting their effectiveness as sinks under field conditions. To enhance sink strength, we experimentally increased fruit attractiveness by application of a fermentation-based attractant solution (apple cider vinegar, red wine and sugar). In laboratory two-choice assays, this treatment significantly increased oviposition across most plant species while developmental success remained low. This effect was particularly pronounced for Pyracantha coccinea and Sorbus aucuparia. Our results suggest that combining behavioral manipulation with developmentally unsuitable host plants may enhance ecological trap function. Exploiting maladaptive host choice in polyphagous pests using attractant-enhanced dead-end plants may thus offer a novel pathway toward reducing dependence on insecticides in berry production systems.
Multisite fungicides, such as mancozeb, have been increasingly adopted for the management of Asian soybean rust (Phakopsora pachyrhizi), as an alternative to improve the control efficiency and to prevent resistance of site-specific fungicides often used in agriculture. Therefore, two experiments were carried out to evaluate the association of different adjuvants with mancozeb under simulated rainfall conditions focusing on both their effects on leaf-surface retention and their control of Asian soybean rust (P. pachyrhizi) (ASR) in soybean crops. Four adjuvants - phosphate alkyl ester (Ochima), soybean methyl ester (Strides), lecithin and propionic acid (LI 700), heptamethyltrisiloxane (Silwet L-77 AG) and a natural polymer (J-S) associated with mancozeb (Unizeb Gold) were evaluated in both experiments. The results demonstrated that simulated rainfall of 20 mm negatively interfered with the retention of the fungicide mancozeb (Unizeb Gold) on the leaf. The addition of the adjuvants phosphate alkyl ester (Ochima), soybean methyl ester (Strides), and heptamethyltrisiloxane (Silwet) improved the retention of the fungicide mancozeb (Unizeb Gold) on soybean leaves when simulated rainfall occurred 120 min after application for Ochima and Strides and 180 min after application for Silwet. The adjuvant Strides improved the performance of Unizeb Gold in controlling Asian soybean rust in soybean crops under simulated rain 120 min after application, whereas the adjuvant Ochima promoted increased yield when associated with Unizeb Gold under the same conditions.
Apple stem pitting virus (ASPV) poses a significant threat to the apple and pear industry worldwide; However, current diagnostic methods rely on laboratory-based techniques that are time-consuming and ill-suited for largescale field surveillance, creating an urgent need for rapid and reliable detection tools. In this study, we developed two optimized, distinct diagnostic platforms to target ASPV: a colloidal gold immunochromatographic assay (GICA) for rapid visual detection and a reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for sensitive molecular detection. The GICA was established using optimized polyclonal antibodies against ASPV, while the RT-LAMP assay employed a newly designed set of primers targeting the conserved region of the ASPV coat protein gene (cp). Both assays exhibited high specificity for ASPV without cross-reacting with other common viruses. The GICA test strip could detect ASPV in sap diluted up to 1:1000 (10- 3), providing results within 5 min. The RT-LAMP assay demonstrated superior sensitivity, reaching a detection limit of 10-4, which was 100 times more sensitive than conventional RT-PCR (10- 2). We successfully developed a rapid GICA test strip and a highly sensitive LAMP assay to detect ASPV. We propose an integrated strategy that combines the GICA strip for on-site preliminary screening with the RT-LAMP assay for accurate laboratory confirmation. This two-tiered approach offers a powerful, efficient, and cost-effective solution for epidemiological monitoring and quarantine inspection of ASPV, significantly enhancing disease control capabilities in the field.
The effects of sex pheromone dose and composition, unsaturated hydrocarbon, trap design, and trap maintenance on trapping efficiency for the striped rice stem borer, Chilo suppressalis, were independently evaluated in Zhejiang, China, using a commercialized ternary sex pheromone blend as a benchmark. Field trials indicated that increasing pheromone dosage did not affect daily or cumulative male catches during the early trapping period, but significantly increased catches over the entire trapping period, indicating that higher pheromone loads primarily extend lure longevity rather than enhance the initial attractiveness. Incorporating (Z)-11-hexadecen-1-ol, an alcohol produced in the female gland, along with the unsaturated alkenes (3Z,6Z,9Z)-tricosatriene and (Z)-9-pentacosene, commonly known as cuticular hydrocarbons or type-II pheromone components, significantly increased male catches across multiple field trials. Comparisons among six trap designs revealed that basin and delta traps were more effective for detection, whereas the basin trap alone was optimal for mass trapping. Furthermore, adding odorless oil or periodically replacing water in basin traps further enhanced trapping efficiency for mass trapping. Understanding these factors that influence detection and mass trapping for C. suppressalis will help strengthen and refine sex pheromone-based pest management for the pest.
