Yujiao Wang

Systematic field data on adjuvant-amended microbial-derived pesticides against L. pratensis in arid, high-ultraviolet cotton regions remain scarce. This study systematically evaluated the laboratory toxicity and field efficacy of four kinds of microbial-derived pesticides (abamectin, emamectin benzoate, B. bassiana, and M. anisopliae) and their combinations with adjuvants against L. pratensis in Xinjiang cotton fields. As a comprehensive regional study, this work elucidates the differential enhancement patterns of d-limonene and mineral oil on antibiotic insecticides and entomopathogenic fungi, providing targeted field data for pesticide reduction strategies. The laboratory toxicity of seven microbial-derived pesticides was determined using the leaf-tube residual film method. Four effective agents were selected and combined with d-limonene or mineral oil for field efficacy trials. Abamectin and emamectin benzoate exhibited rapid and high insecticidal activity, with 48 h LC₅₀ values of 1.198 mg/L and 3.424 mg/L, respectively. The two entomopathogenic fungi exhibited slower insecticidal activity than the chemical insecticides but maintained relatively stable control effects throughout the observation period. In field trials, when abamectin or emamectin benzoate was applied at a 30% reduced rate in combination with mineral oil or d-limonene, the control efficacy was equivalent to or higher than that of the full-rate application of the pesticide alone. The treatment of abamectin (4.20 g a.i./hm²) plus mineral oil achieved the highest control efficacy (89.24%) at 3 days post-treatment. For B. bassiana and M. anisopliae, reduced-rate adjuvant-amended treatments showed numerically higher initial and residual efficacy than the full-rate single-agent fungal treatments. The treatment of M. anisopliae (7.35 × 10¹² spores/hm²) plus d-limonene reached 70.50% efficacy at 7 days post-treatment, which was significantly higher than that of the full-rate fungal treatment alone. No phytotoxicity symptoms were observed on cotton plants. Under the tested conditions, the rational combination of microbial-derived pesticides with appropriate adjuvants demonstrates the potential for a 30% reduction in pesticide dosage while maintaining or improving field efficacy, providing region-specific reference for the sustainable management of L. pratensis in Xinjiang cotton fields.

The practical efficacy of Azadirachtin (AZA)—a botanical insecticide valued for its strong antifeedant activity—is often undermined by its poor environmental stability, arising from rapid photolysis and thermal decomposition. Herein, amino-modified mesoporous silica nanoparticles (MSNs) were employed as nanocarriers to encapsulate AZA, yielding the AZA@MSNs−NH₂ nanoinsecticide. Under UV irradiation (254 nm), the degradation rate of AZA@MSNs−NH₂ was more than 35% lower than that of commercial AZA after 24 h of exposure. In biosafety tests, MSNs at 50–800 mg/L enhanced cotton seed germination and seedling growth, whereas MSNs below 200 mg/L caused no observable harm to zebrafish survival. Free AZA (0.5–10 mg/L) showed limited efficacy in bioassays against Helicoverpa armigera and Apolygus lucorum, reducing larval weight gain only marginally in the former (mortality < 5%) and performing poorly against the latter. In contrast, AZA@MSNs−NH₂ significantly boosted both growth inhibition and lethal effects against both pests, yielding > 80% growth inhibition and 62.65% corrected mortality for H. armigera, as well as strong lethality toward A. lucorum. Overall, this work confirms that nanoformulation of AZA not only circumvents its physicochemical drawbacks but also boosts its insecticidal performance against cotton pests, supporting the advancement of sustainable cotton pest control.

Nanopesticides are pesticide formulations in which intentionally designed nanoscale carriers shape how an active ingredient (AIng) is deposited, transformed, and released. These systems can improve retention and efficacy, but carrier complexity introduces challenges: nanomaterials can transform in real soil–water matrices, reshaping exposure and risk. These processes are hard to quantify because test protocols and risk assessment frameworks for nanopesticides remain underdeveloped. In this review, we relate design choices across major carrier families—including polymer and lipid particles, nanoemulsions, porous inorganic carriers, and bio-based nanomaterials—to transformations in soil–water systems. We then connect these transformations to ecotoxicological evidence across key non-target taxa. We also address a central “measurement gap” in current risk assessment. Many standard tests were developed for dissolved chemicals. As a result, they do not capture (i) particle stability in realistic matrices, (ii) particle-bound versus dissolved (and ion-released) forms, or (iii) time-resolved exposure. Finally, we propose a Safe-and-Sustainable-by-Design roadmap that prioritizes low-hazard materials, predictable degradation, life-cycle thinking, and staged data generation to enable scalable, field-relevant adoption.

Characterizing the genetic diversity and population structure can determine whether there is gene flow of the natural population of Helicoverpa armigera (Hübner) under disparate climate and habitat conditions in Northwest China. In this paper, H. armigera was genotyped in various regions of Xinjiang using Genotyping-by-Sequencing (GBS). The samples were compared using the single nucleotide polymorphism (SNP) and insertion deletion (InDel) marker data. The SNPs were used to analyze the population structure and five subgroups were obtained, which was further confirmed by principal component analysis (PCA). The phylogenetic tree identified five cluster populations of H. armigera . The average values of polymorphic information content (PIC) and genetic differentiation index (Fst) are 0.1783 and 0.1293, respectively, which are at a high level. The phylogenetic tree differentiation also indicates that the genetic diversity of cotton bollworm populations in different regions of Xinjiang is low diversity, moderate differentiation, and widespread gene flow. According to correlation analysis of the source of feeding on host plants (Bt cotton and non Bt crops) of H. armigera, seven SNPs with significant differences were obtained. The most significant SNP sequence was compared with the whole genome of H. armigera , and 10 candidate genes were screened. Whether the candidate genes function are related to Bt resistance needs further verification. This study can provide scientific basis for screening Bt resistance genes and formulating refuge strategy of H. armigera in Northwest China.

Chemosensors based on traditional fluorescent dyes have always contributed to the development of chemical sensor areas. In this review, the rhodamine-based chemosensors’ improvements and applications from 2018 to 2022 are discussed, mainly focusing on cations (metal ions and H⁺), anions (CN⁻, F⁻, etc.), and small bio-functional molecules’ (thiols, amino acids, etc.) detection. Specifically, this review highlights the detection target, detection limit, detection solution system, detection mechanism, and performance of the rhodamine-based sensors. Although these rhodamine-based sensors are well developed, their repeatability and sensitivity still need significant improvement. This review is expected to bring new clues and bright ideas to researchers for further advances in rhodamine-based chemosensors in the future.