The Astragalus polysaccharides (APS) are important bioactive components of Astragali Radix, the dry root of Astragalus membranaceus, which has been used in traditional Chinese medicine. In this review, the extraction conditions and extraction rates of APS are first compared for water, microwave-assisted, ultrasonic wave, and enzymatic hydrolysis extraction methods. Some studies have also shown that different methods can be combined to improve the extraction rate of APS. Subsequently, the chemical composition and structure of APS are discussed, as related to the extraction and purification method. Most studies have shown that APS is mainly composed of glucose, in addition to rhamnose, galactose, arabinose, xylose, mannose, glucuronic acid, and galacturonic acid. We also reviewed studies on the modification of APS using chemical methods, including sulfated modification using the chlorosulfonic acid–pyridine method, which is commonly used for chemical modification of APS. Finally, the pharmacological activities and mechanisms of action of APS are summarized, with a special focus on its immunoregulatory, antitumor, anti-inflammatory, and antiviral effects. This review will serve as a valuable resource for the research on APS.

With the rapid development of intelligent agriculture and precision agriculture, computer image processing technology has been widely used to solve various problems in the agricultural field. In particular, the advantages of convolutional neural networks (CNNs) in image classification have also been widely used in the automatic recognition and classification of plant diseases. In this paper, a deep convolutional neural network named LeafNet capable of recognizing the seven types of diseases from tea leaf disease images was established, with an accuracy of up to 90.23%, aiming to provide timely and accurate diagnostic services in the remote and topographic tea plantation in China. At the same time, the traditional machine learning algorithm is applied for comparative analysis, which extracts the dense scale-invariant feature transform (DSIFT) of the image and constructs the bag of visual word (BOVW) model to express the image based on the DSIFT descriptor. The support vector machines (SVMs) and multilayer perceptron (MLP) were used to identify tea leaf diseases, with an accuracy of 60.91 and 70.94%, respectively.

Introduction: Atractylodes chinensis (DC.) Koidz, a medicinal herb in the Chinese Pharmacopoeia, is grown in sandy soils. However, water scarcity in the Horqin Sandy Land limits its growth, and the effects of irrigation remain poorly studied. This research aimed to determine how irrigation levels affect its yield and quality through leaf structure, physiology, and secondary metabolism. Methods: A field experiment tested five irrigation rates (4500–2500 m ³ ·hm ⁻² ). We measured leaf anatomy, photosynthetic parameters, yield, and quality indicators. Results and discussion: Irrigation altered leaf anatomy (palisade and spongy tissue thickness). Photosynthetic pigment content showed a initial increase then decrease with reduced irrigation. An irrigation rate of 3500 m ³ ·hm ⁻² maintained high electron transfer efficiency, carbon assimilation, and key enzyme activity for alkaloid synthesis. While yield declined with less water, quality peaked at moderate irrigation. Moderate irrigation (3500 m ³ ·hm ⁻² ) best balances yield and quality by supporting both physiological function and secondary metabolism. These findings offer a theoretical basis and practical guidance for cultivating A. chinensis in water-limited sandy lands under climate change.

Background: Continuous cropping is a major constraint that limits the sustainable cultivation of medicinal plants. However, the effects of continuous cropping on yield, medicinal quality, and the rhizosphere soil microecological environment of Atractylodes chinensis , particularly in the Horqin Sandy Land, remain unclear. In this study, we conducted a field experiment with continuous cropping and rotation systems to compare the yield, bioactive compound content, soil chemical properties, and rhizosphere microbial communities of A. chinensis and to further elucidate their potential relationships. Methods: Plant and soil samples were collected to assess plant yield and bioactive compounds, soil chemical properties, and soil microbial communities using high-throughput sequencing, followed by bioinformatic analysis of the sequencing data. Results: Compared with crop rotation, continuous cropping significantly reduced yield and the contents of major bioactive compounds, including atractylodin, atractylon and β-eudesmol. Continuous cropping significantly increased soil pH, electrical conductivity (EC), and available potassium, and decreased alkali-hydrolyzable nitrogen and organic matter (OM). Additionally, continuous cropping decreased fungal richness (Chao1 index) and increased bacterial diversity (Shannon index) and evenness (Pielou’s evenness). Fusarium and Volutella were significantly enriched, whereas Nocardioides and Arthrobacter were depleted. The predicted microbial functional potential associated with carbon and nitrogen cycling significantly decreased under continuous cropping. The correlation analysis revealed that the yield of A. chinensis was negatively correlated with soil EC and positively correlated with OM content, and the relative abundances of Heydenia and Enterocarpus . Atractylon content was positively correlated with Aleuria and Acremonium and negatively correlated with Volutella . Conclusion: These findings demonstrate that continuous cropping reduces the yield and medicinal quality of A. chinensis in the Horqin Sandy Land and is associated with the deterioration of several soil chemical properties and dysbiosis of the rhizosphere microbial community. This study provides novel insights into the continuous cropping constraint associated with A. chinensis and its ecological consequences in the Horqin Sandy Land and establishes a theoretical foundation for optimizing cropping systems, maintaining soil ecological health, and improving the yield and quality of this medicinal herb.

Fangfeng (Saposhnikovia divaricata) is a perennial plant belonging to the Umbelliferae family, and is widely cultivated as a traditional Chinese medicine plant used to treat various diseases in northern China. In August 2022, a widespread leaf spot disease emerged on the Fangfeng leaves across a 2.5-acre farmland located in the Naiman District of Tongliao City, China ( 44°17' N; 121°29' E), where 5,000 acres of Fangfeng had been cultivated. The incidence of the disease approached 100% in the two-year-old Fangfeng crops within the specific fields. Small, pale yellow spots were observed on the affected leaves of the Fangfeng plant. Diseased tissue pieces (5 mm) from symptomatic leaves were sterilized in 75% ethanol for 5 s and 1% NaClO for 25 s, then rinsed three times with sterilized distilled water and placed on potato dextrose agar (PDA) at 26°C in the dark for 7 days. Thirty-three isolates were obtained from 11 diseased leaf samples, representing one fungal species. The cultures had a dark olive color on both sides, accompanied by the presence of loose, cottony mycelium on the surface (Simmons, 1992). The conidiophores were light brown with clear separation, solitary or in clusters and ranged from 5.5 to 44.4 μm. Conidia are obpyriform with a cylindrical beak ( 0 to 22 µm in length) in short chains on Potato Carrot Agar (PCA). Conidia averaged 15.3 × 47.4μm with one to five transverse septa and zero or two occasional longitudinal septa. It is similar to those described as Alternaria sp. based on morphological characteristics (Simmons, 2007). The ITS, TEF1 and RPB2 gene fragments of isolates FFYB2 and FFYB4 were amplified with the primer pairs ITS5/ITS4, EF1-728F/EF1-986R and RPB2-5F/RPB2-7cR (White et al, 1990; Carbone and Kohn, 1999; Berbee et al., 1999; Liu et al., 1999) and submitted to GenBank (ITS, PP976058 and PP976059; TEF, PQ096003 and PQ096004; RPB2, PQ120838 and PQ120839). The three gene sequences ITS+ TEF1+ RPB2 were aligned in Clustal X 1.83 with equal weight and a phylogenetic tree was constructed in Mega 7.0.26 software (He et al., 2021). Finally, it was identified as A. alternata based on morphological and molecular characteristics. 36 Fangfeng leaves from six 8-month-old plants were utilized to assess the pathogenicity of the FFYB2 isolate, encompassing the control. All of PDA plugs (0.5 cm in diameter) colonized with the isolate and without the isolate were placed on the pinholes by a sterilized needle of the Fangfeng leaf surface sterilized with 75% alcohol-tampon, then removed after 48 h. On the fifth day, brown lesions (5 mm) appeared on 15 out of 18 Fangfeng leaves inoculated. No lesions were observed on 18 control leaves inoculated with PDA plugs. The fungi were re-isolated from the new lesions after a 7-day post-inoculation period, utilizing the aforementioned method, and their morphology was found to be identical to that of Alternaria sp.. Although A. divaricata was previously identified as a pathogen in Badong County (30°28'N; 110°29'E) of Yichang City, Hebei Province, China (He et al., 2021), the research results were deficient in providing details on the severity, symptoms, pathogenicity tests of the disease, and other relevant aspects. To our knowledge, this is the first report of A. alternata causing Fangfeng leaf spot in China. Fangfeng Alternaria leaf spot has caused severe economic losses in the region. Effective management strategies for this disease were urgently needed.