BACKGROUNDPlants emit volatile organic compounds (VOCs), which serve as critical cues for herbivorous insects to locate hosts for feeding and oviposition. Understanding how adults identify host plants is essential to develop pest management strategies, particularly for hemiedaphic insects like click beetles, the larvae of which are significant soil-dwelling pests. To investigate click beetle attraction towards plant VOCs and their relevance for oviposition, we tested the attractiveness of constitutive VOCs (emitted by intact plants) and damage-induced VOCs (released by chopped plants) from 11 plant species to male and female Agriotes sputator beetles.RESULTSAgriotes sputator beetles exhibit plant species-specific olfactory preferences, which are influenced by beetle sex and female maturity and differ between constitutive and damage-induced VOCs. Female beetles showed the greatest attraction to buckwheat VOCs, especially during their main oviposition period, whereas males were more attracted to clover and ryegrass. EAG recordings show strong female antennal responses to ryegrass, carrot, maize, wild carrot, barley, and buckwheat VOCs, while male antennae responded significantly only to peas. Antennae from female beetles show overall stronger responses to constitutive VOCs than those of males (P = 0.02).CONCLUSIONThese findings facilitate the development of new approaches for Agriotes pest management. Understanding preferred plant VOCs aids in identifying attractive semiochemicals that can be used for monitoring female beetles. Additionally, recognizing attractive plants aids wireworm management by either avoiding them in crop rotations before sensitive crops (thus reducing oviposition) or by attracting beetles to specific areas where they can be targeted by control measures. (c) 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The increasing expenses and environmental repercussions associated with phosphorus (P) fertiliser underscore the necessity for precision-managed application methods. These changes affect pastoral systems, where cool-season grasses like perennial ryegrass and meadow fescue form beneficial relationships with Epichlo & euml; endophytes. Understanding how fertilisers influence these endophytes, host grasses, and insect pests is crucial, as Epichlo & euml; endophytes enhance resistance to some herbivorous insects. This study examined the indirect impact of various P fertiliser regimes on cool-season grasses, which serve as food sources for porina larvae (Wiseana copularis), a significant pasture pest in New Zealand. Endophyte-infected (Epichlo & euml; sp. LpTG-3 strain AR37) perennial ryegrass and meadow fescue infected with E. uncinata (strain MaxR (AR1017)), alongside their endophyte-free counterparts were grown in P-enriched soil with varying Olsen P levels (9, 18, 28, and 78 mg/L). Freeze-dried foliage was added to semi-synthetic diets and fed to porina larvae in a no-choice assay. Measurements included diet consumption, porina survival, weight gain. Measurements in foliage included fungal alkaloid concentration, fungal biomass, and plant nutrient levels. Endophyte infection of AR37 and MaxR significantly reduced porina diet consumption, larval weight gain and survival irrespective of soil Olsen P levels to the plant. Loline alkaloid concentration in MaxR-infected herbage increased with increasing soil Olsen P levels while fungal mass remained unchanged. In endophyte-free grasses, porina larvae significantly increased their diet consumption, weight gain and survival as the Olsen P level available to the host plant increased. While endophyte strains AR37 and MaxR continue to protect their hosts under different Olsen P regimes, these results suggest that the improved performance of porina on endophyte-free plants is largely driven by P-induced changes in food quality. Here, we discuss the implications of porina damage in New Zealand pastures in the context of decreasing P availability.

The green-belly stink bug is an early pest in the second crop of corn, following soybean. The dynamics of infestations by this pest in systems where corn is defoliated in the early stages is still unknown. Therefore, the objective was to evaluate the feeding of the stink bug on corn subjected to early defoliation. In a greenhouse, used a 2 x 4 factorial design, with two cultivars: BRS3042 VTPRO2 and 1F640PRO2, and four treatments: Without stink bug and with plant cutting (WSB-C); With stink bug before cutting (SB-BC); With stink bug after cutting (SB-AC); With stink bug and without cutting (SB-WC), with ten repetitions. Cutting of the plants was performed at the V3 stage, at a height of five centimeters above the soil. Infestation with stink bugs was carried out five days after emergence and/or after cutting, with two stink bugs per pot. The following were evaluated: injury score, height, stem diameter, fresh and dry plant weight. The plants that were not cut (SB-WC) presented the highest values in height and diameter, resulting in injury scores around 1 compared to those that were infested after the cut (SB-AC), which had scores varying between 3 and 4 and had smaller height and diameter. It was concluded that removing the leaf surface impairs the establishment of the corn plant, and with the infestation of the green-belly stink bug, the severity of the damage increases.

Endophytic Fusarium oxysporum strain V5w2 has been suggested to offer the ecosystem service of suppressing Cosmopolites sordidus and other pests that attack tissue culture banana plants in agroecosystems. The effects of endophytic F. oxysporum V5w2 and nutrient supply on C. sordidus in potted tissue culture banana plants were investigated. In the screenhouse, rhizome damage by C. sordidus larvae was lower in F. oxysporum V5w2-inoculated plants than in non-inoculated ones. Banana plants inoculated with F. oxysporum V5w2 were larger and suffered less rhizome damage but with low chlorophyll content. Weights of C. sordidus larvae were not different between those reared on F. oxysporum V5w2-inoculated banana plants and the non-inoculated ones. Larval C. sordidus from nutrient-treated plants had lower weight than those that fed on plants that did not receive nutrients. In the field, fewer adult C. sordidus were found on F. oxysporum V5w2inoculated banana plants than on non-inoculated plants 12 h after insect release. The number of adult C. sordidus and their eggs did not vary between F. oxysporum V5w2-inoculated banana plants and controls at the end of the experiment. Adult C. sordidus did not discriminate between nutrient-treated banana plants and those without nutrient treatment. However, non-beneficial interactions between F. oxysporum V5w2 and plant-parasitic nematodes negate the chances of its application as an endophytic biological control agent. In conclusion, while F. oxysporum V5w2 is not quite viable for application as an endophytic biological control agent for C. sordidus and other banana pests, this fungus may still have some potential to offer alternative ecosystem services through the provisioning of pest-inhibitive organic compounds.

BACKGROUND: Fertiliser applications are well-established tools in pasture-based agricultural landscapes. This study focuses on the impact of phosphorus (P) fertiliser on grass grub (Costelytra giveni), a major pasture pest. This research investigates the interplay between P, plant growth, and grass grub fitness in Epichlo & euml; endophyte-infected perennial ryegrass (Epichlo & euml; sp. LpTG-3 strain AR37) and meadow fescue infected with E. uncinata (strain MaxR; AR1017), alongside their endophyte-free counterparts. In a glasshouse trial, plants were grown in P-enriched soil with varying Olsen P levels (9, 18, 28 or 78 mg L-1), and grass grubs were introduced. Their survival and weight gain, and plant performance were measured. In a bioassay, grass grubs were placed in specimen vials with P-enriched soils (Olsen P levels 9, 18, 28 and 78 mg L-1) and provided with identical plant material to assess their diet consumption and weight gain. RESULTS: In the glasshouse trial, results highlighted a notable decrease in the survival of grass grub on plants infected with MaxR endophyte, but not with AR37, as well as increasing soil Olsen P levels in both plant species. While grass grub decreased plant performance at the low Olsen P level (9 mg L-1), this effect diminished with increasing P. Likewise, results from the bioassay showed a decrease in diet consumption with increasing soil Olsen P levels. In both trials increasing Olsen P levels correlated with diminished grass grub performance, revealing a nuanced relationship between soil fertility and pest dynamics. CONCLUSION: The study underscores the pivotal role of selected Epichloe endophyte-grass associations in mitigating grass grub damage across varying phosphorus levels. This study highlights the potential to integrate P applications for sustainable pest control against grass grub. Further field trials are required to validate these findings. (c) 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Myochrous armatus Baly, 1865 (Coleoptera: Chrysomelidae) has expanded its occurrence significantly into soybean-growing areas of Brazilian Cerrado and became an important early-season soil pest. Experiments were performed under field conditions from 2020 to 2023 to assess several aspects: (1) population behaviour over crop season and offseason; (2) day/night behaviour during the early stages of soybean plants and (3) injury to plants and potential damage to soybean yield to establish the Economic Injury Level (EIL). Adults of the M. armatus population presented a season-long abundance during the specific period from late October to January, with major captures in November and December (end of Spring), either inside or on the edge of soybean fields. Weeds and volunteer plants of corn and cotton hosts adults and eggs. These findings suggest an univoltine life cycle. Behavioural assessments revealed that M. armatus does not exhibit a specific day, night or crepuscular behaviour, performing deeds at any time. The majority of insects (40% to 70%) were found in the soil throughout the day and night. Adults feed on soybean plants by scraping or cutting the stem, cotyledon, petiole and apical sprouting. Their preference is initially for the stem and cotyledon (up to 14 days after emergence), and later for the petiole (after 21 days of emergence). After 7 days of coexistence at V1-V3 soybean stages, we observed a potential yield reduction of 35% for each insect per plant. Dynamic EIL estimations are between 0.4 and 1.9 adults per row metre, depending on the grower productivity expectation, control costs and soybean market value. Our results are fundamental for establishing Integrated Pest Management for M. armatus in soybean and other crop systems.

Plants have limited resources to allocate to defences against infection and herbivory. While interactions between plant responses to microbial and herbivore attack are complex, it is often the case that the induction of one response will act antagonistically to the other. Recent studies have shown that plant growth promoting rhizobacteria, which improves overall plant health and general stress resistance, can enhance both anti-microbial and anti-herbivore defences. We investigated how soil application of the biofungicide Serenade ASO (Bacillus subtilis strain QST 713), which primes plant defences against fungal and bacterial infection and promotes plant growth, affects anti-herbivore defences by measuring both constitutive and induced defences. We applied Serenade one or two times to the soil of tomato plants and measured the numbers of type IV glandular trichomes on leaves, the weight gain of a generalist caterpillar (beet armyworms; BAW), and the activity of two enzymes associated with defence against insects (polyphenoloxidase and peroxidase). Serenade treated plants grew faster and foliage from treated plants had significantly higher numbers of glandular trichomes and higher polyphenoloxidase and peroxidase activities than untreated plants. However, Serenade treatment did not affect the degree of induction of plant defences when damaged by BAW feeding and did not slow the growth rate of BAW relative to plants not treated with Serenade. Therefore, the biofungicide Serenade increased plant growth and altered the densities of trichomes and the activities of two defensive enzymes in plants, but it did not affect overall susceptibility of the plants to a generalist herbivore.

This article is part of the search for alternatives to the use of pesticides (especially elicitors of resistance) within the context of integrated pest management (IPM). For this reason, resistance triggers based on potassium phosphite were used in the form of oak stem spraying. The aim of the study was to assess the influence of phosphites applied as a commercial product called Kalex. The changes in the immediate environment and the development of root systems and tree crowns (based on defoliation and health indicators) were assessed. The treatment of oak stems with potassium phosphite had no negative effects on the forest environment. The acidity (pH) of the soil did not change nor did the content of Mg and Ca. Phosphorus and potassium from the treatments were taken up by the living part of the bark and transported to the fine roots. However, some of the treatments certainly entered the soil via the logs when it rained. Thus, these elements also reached the vicinity of the roots, where they were present in larger quantities. As a result of leaf loss (defoliation), the crowns of the control trees were more thinned out than those of the trees treated with the phosphite preparation. Over several years, this led to a decrease in the health of the control trees, i.e. a change in the crown architecture (deformation due to the formation of short shoots) expressed in vitality grades. The calculated synthetic damage index (Syn), which takes into account the degree of defoliation and health, was also higher in the control trees than in the treated trees indicating the effectiveness of the treatment with the commercial product Kalex. The fine roots of the treated oaks had more favourable development parameters than the corresponding roots of the control trees especially in terms of length, number and surface area. This increased the ability of the treated oaks to take up the water needed to increase photosynthetic efficiency in order to feed the roots. However, in a situation of extreme drought in 2015 resulted in the death of the fine roots of the oaks (independent of the treatment) and continued the following year. Only in the 2017 season, when soil moisture improved significantly, did the oaks return to the state of root development before the severe drought. As a result, the percentage of dying trees in the treated tree group was statistically lower than in the control group. The treated oaks (especially those that were up to 30% defoliated) survived better during the five-year observation period (2013-2017) and were able to effectively absorb nutrients and water from the soil due to the better condition of their fine roots which was reflected in better shoot development in the crowns (assessed by defoliation, vigour and Syn-index).

Weed harrowing is commonly used to manage weeds in organic farming but is also applied in conventional farming to replace herbicides. Due to its whole-field application, weed harrowing after crop emergence has relatively poor selectivity and may cause crop damage. Weediness generally varies within a field. Therefore, there is a potential to improve the selectivity and consider the within-field variation in weediness. This paper describes a decision model for precision post-emergence weed harrowing in cereals based on experimental data in spring barley and nonlinear regression analysis. The model predicts the optimal weed harrowing intensity in terms of the tine angle of the harrow for a given weediness (in terms of percentage weed cover), a given draft force of tines, and the biological weed damage threshold (in terms of percentage weed cover). Weed cover was measured with near-ground RGB images analyzed with a machine vision algorithm based on deep learning techniques. The draft force of tines was estimated with an electronic load cell. The proposed model is the first that uses a weed damage threshold in addition to site-specific values of weed cover and soil hardness to predict the site-specific optimal weed harrow tine angle. Future field trials should validate the suggested model.

Insect pests cause severe crop damage, resulting in substantial economic losses and threats to global food security. Conventional insecticides are low-cost chemical agents that kill the target insects and some non-specific beneficial organisms. Due to their toxic and non-biodegradable nature, these conventional insecticides persist in the environment, thus causing pollution and accumulating in the food chain. The development of novel insecticidal products based on double-stranded (dsRNA)-based RNA interference (RNAi) technology is a sustainable tool to effectively control insect pests. The dsRNA-based insecticides are known for their specificity, non-toxicity, and biodegradability. The current review introduces the dsRNA-based RNAi technique as a novel tool to control crop insect pests. The review highlights the mechanism behind dsRNA uptake into insect cells. Furthermore, it discusses the commercial aspects of different dsRNA-based products available in the market, their penetration rates, and public acceptance. The review details the latest developments in the field and the regulatory landscape regarding the technology. The advantages and limitations of dsRNA-based insecticides are discussed, and future research directions to overcome the potential challenges have been briefly suggested. The dsRNA-based insecticidal products may be a better alternative to conventional insecticides, thus delineating the resistance among insects and increasing agricultural productivity.