Pest Management Science最新文献

Background: Meloidogyne incognita is a highly damaging pathogenic nematode that causes significant annual economic losses. Therefore, the development of reliable biological control agents against M. incognita is imperative. The Bacillus velezensis RKN1111 strain, isolated from inter-root soil, demonstrates the ability to directly kill M. incognita. In this study, we investigated the effect of RKN1111 in inducing resistance to M. incognita in Cucumis sativus and examined changes in the content of immune-responsive substances in the induction-treated cucumber plants.

Result: The RKN1111 treatment reduced the number of root galls in infected cucumbers, with a maximum reduction of 78.19%. RKN1111 stably colonized cucumber roots, reaching 3.65 × 10⁶ CFU/g in 3 days. The approach and infestation rates of M. incognita on RKN1111-induced treated cucumber root tips declined at varying time points. Furthermore, RKN1111 induced significant increases (P < 0.05) in hydrogen peroxide (H₂O₂) and superoxide anion (O^2-) contents, as well as in the callose deposition area in cucumber, by up to 59.84, 83.28, and 61.59%, respectively.

Conclusion: RKN1111 has been demonstrated to stably colonize cucumber root systems and defend against M. incognita infestation by inducing systemic resistance in the host plant. Additionally, RKN1111 elevated the levels of immune-responsive substances in cucumber plants. RKN1111 has great potential for application in the integrated pest management of M. incognita. © 2025 Society of Chemical Industry.

Background: Herbicides based on protoporphyrinogen IX oxidase (PPO; EC 1.3.3.4) are widely used for weeding control in agricultural fields to safeguard food security. PPO herbicides, because of their low dosage, rapid action on weeds, slow accumulation in the environment and low toxicity to mammals, have become an important field of research in the development of new herbicides. This study presents a novel molecular scaffold with remarkably potent herbicidal activity.

Results: A series of novel oxime ether derivatives containing 1,5-dimethyl-6-thioxo-1,3,5-triazinane-2,4-dione 6a-6z were designed and synthesized based on bioisosterism and substructure splicing, and characterized by ¹H and ¹³C nuclear magnetic resonance spectroscopies, and high-resolution mass spectrometry. The configuration of compound 6u was confirmed by single-crystal X-ray diffraction. Compound 6r displayed excellent herbicidal activity of >95% against Echinochloa crus-galli, Digitaria sanguinalis, Medicago sativa and Conyza canadensis at a dosage of 37.5 g hm-2 in the glasshouse. At a dosage of 75 g hm-2, 6r was safe for application on rice and showed low toxicity (>200 μg g-1) towards Apis mellifera. Transcriptomics analysis of E. crus-galli treated by compound 6r, using oxadiazon as a positive control, revealed the compound's mode-of-action. There were eight metabolic and biosynthetic pathways of DEGs containing 'photosynthesis', 'porphyrin metabolism', 'carotenoid biosynthesis' and so on between 6r and oxadiazon as same. Scaffold94.443 (coproporphyrinogen-III oxidase) as upstream protoporphyrinogen IX changes were downregulated with quantitative reverse transcription PCR combined analysis treated 6r and oxadiazon in chlorophyll biosynthesis. Compound 6r target may be PPO and the NtPPO inhibitory effects, as represented by Ki, was 30.34 nm in vitro. Molecular docking showed that 6r could form two hydrogen bonds with Arg98.

Conclusion: Through bioisosterism and substructure splicing, we successfully developed compound 6r as lead compound exhibiting herbicidal activity, with no harm to rice and honeybees. Further development of herbicides based on this scaffold is warranted. © 2025 Society of Chemical Industry.

Background: Ips cembrae is serious forest pest of European larch (Larix decidua). The negative impacts on nontarget invertebrates of the use of different I. cembrae trapping methods has not yet been evaluated, although mortality of nontarget invertebrates may occur.

Results: Between 2016 and 2022, the impact of different I. cembrae trapping methods on nontarget invertebrates was assessed. Four trapping methods (slot traps, insecticide-treated tripods, logs and trees) baited with the pheromone lure Cembräwit were tested. Based on larval feeding habits, the captured nontarget invertebrates were grouped into four feeding types: predators, phloexylophagous, saproxylophagous and mycetophagous. The results indicate that predators, especially the clerid beetle Thanasimus formicarius, were the most negatively affected group of nontarget invertebrates. A negative effect on a number of IUCN Red List species also was shown, particularly on Corticeus fraxini (Tenebrionidae). The results show that Cembräwit-baited slot traps capture not only I. cembrae, but also other serious forest pests such as I. sexdentatus and Pityogenes chalcographus. The overall effect of different trapping methods on I. cembrae population densities has not been studied; however, our results indicate that the use of insecticide-treated methods has a negative effect on I. cembrae predators.

Conclusion: The negative effect on the predators may be sufficiently large to outweigh any benefits gained from a reduction in I. cembrae numbers resulting from trapping. Therefore, in order to reduce the negative impacts on nontarget invertebrates, properly timed and consistent salvage logging should be used rather than insecticide-treated trapping methods. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The cover image is based on the article Psyllid-mite interactions promote psyllid fecundity by selecting for a different life history by Pengxiang Wu et al., https://doi.org/10.1002/ps.8539.