Qinghai Zhang

Pseudostellaria heterophylla is increasingly utilized as a functional food ingredient in East Asian cuisines, valued for its bioactive polysaccharides and saponins. Concurrently, the scarcity of genetically diverse and regionally adapted cultivars poses a significant challenge to the sustainable production of this crop. This study integrates the evaluation of agronomic, yield, and nutritional traits with electrical parameters to evaluate 13 P. heterophylla varieties from diverse geographical origins. Significant varietal differences were observed in intracellular water metabolism, nutrient transport, and metabolic activity, as reflected by intrinsic electrical parameters (p < 0.05). Among the tested varieties, “Zheshen I” exhibited the best results, with a fresh weight of 675.74 kg/667 m² and a dry weight of 267.41 kg/667 m². “Zheshen II” contained the highest polysaccharide content (49.27%), while “Zheshen IV” showed the highest saponin content (2.83%). Grey relational analysis identified six varieties—“Guishen I,” “Zheshen IV,” “Xuanshen I,” “Shitai I,” “Anguo,” and “Space breed”—as having superior comprehensive performance, making them suitable for promotion and cultivation in the Guizhou region. Notably, “Guishen I” (the current main cultivated variety) and “Shitai I” (a local variety) ranked among the top performers, suggesting the potential of our experimental evaluation to reflect practical cultivation outcomes. Overall, this study provides quantitative data on the nutritional components of P. heterophylla to support the standardized procurement of raw materials for functional foods, while simultaneously identifying potentially superior genotypes based on phenotypic vigor for regionally adapted breeding.

Although zinc‐fulvic acid chelate (Zn‐FA) can efficiently reduce the cadmium (Cd) accumulation in rice grains, little is known about the impacts on other beneficial elements (such as zinc) levels in rice, along with the optimal concentration and underlying molecular mechanisms. The aim of this study is to investigate the effect of Zn‐FA on Cd accumulation in rice and its metabolic mechanism through pot experiments. The results demonstrated that Zn‐FA treatments significantly reduced Cd and increased Zn content in rice grains, with 10 g/L Zn‐FA identified as the optimal concentration for spraying. Zn‐FA treatment primarily reduced the translocation of Cd from stems to grains, thereby limiting Cd accumulation in the grain. Metabolomic analysis revealed that Zn‐FA application significantly altered the metabolic profiles of rice leaves under Cd stress. In Yixiangyou586 (YXY586), Zn‐FA involved the upregulation of flavonoids with antioxidant properties, along with associated pathways such as flavonoid biosynthesis, flavone, and flavonol biosynthesis; similarly, in Gengxiangyou703 (GXY703), Zn‐FA modulated the metabolism of flavonoids. Under Zn‐FA application, the reduction of Cd content and increase of Zn accumulation in rice grains are mainly related to the altered metabolism of phenolics, especially flavonoids in rice leaves. The findings of this study offer new insights into the mechanism of Zn‐FA in reducing Cd content in rice, thereby providing a scientific foundation and technical support for ensuring safe crop production and promoting ecological safety.

The rapid and ultrasensitive detection of Salmonella holds strategic significance for food safety surveillance and public health protection systems. This study innovatively developed a label-free biosensing platform based on the synergistic integration of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas12a and the fluorescent deoxyribozyme Aurora for the efficient detection of foodborne Salmonella. The detection mechanism operates through a molecular cascade reaction: target-activated Cas12a protein specifically degrades Aurora deoxyribozyme via its trans-cleavage activity, thereby abolishing the enzyme’s catalytic capability to convert 4-methylumbelliferyl phosphate (4-MUP) into the highly fluorescent product 4-methylumbelliferone (4-MU). This cascade ultimately enables quantitative target analysis through fluorescence signal attenuation. Following systematic optimization of critical reaction parameters, the biosensing system demonstrated exceptional analytical performance: a detection limit of 1.29 CFU/mL with excellent linearity (R² = 0.992) spanning six orders of magnitude (1.65 × 10¹–10⁶ CFU/mL), along with high specificity against multiple interfering bacterial strains. Spike-and-recovery tests in complex food matrices (milk, chicken, and lettuce) yielded recoveries of 90.91–99.40% (RSD = 3.55–4.72%), confirming robust practical applicability. Notably, the platform design allows flexible detection of other pathogens through simple replacement of CRISPR guide sequences.

Pseudostellaria heterophylla (or Taizishen in Chinese), a medicinal, edible, and ornamental Chinese herb, is seriously affected by leaf spot disease (LSD). Oligochitosan is a natural agricultural antibiotic that is produced via the degradation of chitosan, which is deacetylated from chitin; pyraclostrobin is a broad-spectrum and efficient strobilurin fungicide. In this work, the ability of pyraclostrobin, oligochitosan, and their formula to manage P. heterophylla leaf spot disease and their role in its resistance, leaf photosynthesis, agronomic plant traits, root growth, and root quality were studied. The results show that the joint application of oligochitosan and low-dosage pyraclostrobin could control LSD more efficiently, with control effects of 85.75–87.49% compared to high-dosage pyraclostrobin or oligochitosan alone. Concurrently, the application of this formula could more effectively improve the resistance, leaf photosynthesis, agronomic plant traits, root yield, and medicinal quality of P. heterophylla, as well as reduce the application of pyraclostrobin. This finding suggests that 30% pyraclostrobin suspension concentrate (SC) 1500-time + 5% oligosaccharin aqueous solutions (AS) 500-time diluent can be recommended for use as a feasible formula to manage LSD and reduce the application of chemical pesticides.

China ranks third in the global production of dairy products; however, dairy products are extremely vulnerable to contamination, which leaves harmful effects on the human body. This study assesses the risk classification of hazards, and examines regional and temporal distribution patterns using sample data on dairy products produced in China from 2017 to 2021. The risk value was estimated using the entropy weight method. Both global and local spatial autocorrelations were applied. The findings indicate that the primary high and relatively high-risk substances in circulation and production are veterinary medications, additives, microorganisms, and chromium whereas the main high and relatively high-risk substances in catering are additives, microorganisms, and chromium. Unqualified dairy samples were reported from 2017 to 2021. The categorical sampling of dairy products primarily takes place in western China, and only coliform group and total bacterial counts demonstrated high–high and low–low agglomeration, respectively. The dynamic adjustment of targeted regulatory opinions and regulatory plans is proposed to provide scientific basis for the safe supervision of dairy products through the classification of risk substances and the characteristics of related time and space distribution.

Pseudostellaria heterophylla (Miq.) Pax is a popular clinical herb and nutritious health food. However, leaf spot disease caused by fungal pathogens frequently occurs and seriously influences the growth, quality, and yield of P. heterophylla. In this work, the field control roles of difenoconazole, chitosan, and their combination in the leaf spot disease in P. heterophylla and their effects on the disease resistance, photosynthetic capacity, medicinal quality, and root yield of P. heterophylla are investigated. The results manifest that 37% difenoconazole water-dispersible granule (WDG) with 5000-time + chitosan 500-time dilution liquid had a superior control capacity on leaf spot disease with the control effects of 91.17%~88.19% at 15~30 days after the last spraying, which significantly (p < 0.05) exceeded that of 37% difenoconazole WDG 3000-time dilution liquid and was significantly (p < 0.01) higher than that of 37% difenoconazole WDG 5000-time dilution liquid, chitosan 500-time dilution liquid, or chitosan 1000-time dilution liquid. Simultaneously, this combination could more effectively enhance the disease resistance, photosynthetic capacity, medicinal quality, and tuberous root yield of P. heterophylla compared to when these elements were applied alone, as well as effectively reduce difenoconazole application. This study emphasizes that chitosan combined with a low dosage of difenoconazole can be proposed as a green, efficient, and alternative formula for controlling leaf spot disease in P. heterophylla and enhancing its resistance, photosynthesis, quality, and yield.