American ginseng (Panax quinquefolius) is an important medicinal plant cultivated in China since the 1980s. Its dried roots are used for food, health care products, and medicine in China (Yuan et a...

Northeast China is well known for cultivating ginseng (Panax ginseng and P. quinquefolius). Ginseng roots are threatened by the infection of the most notorious Cylindrocarpon-like fungi (CLF), which are a complex containing important soilborne pathogens. Although the disease is economically important, little is known about the genetic diversity and population structure of the pathogenic CLF complex. This knowledge will help in developing effective disease management strategies. To conduct this study, diseased ginseng roots were collected from 12 regions representing the main ginseng-growing areas in Northeast China, and CLF were isolated. A total of 169 isolates with CLF anamorph were identified in two Dactylonectria species and six Ilyonectria species using morphological and molecular methods. Cross pathogenicity tests showed that all species were pathogenic to both P. ginseng and P. quinquefolius, and most of them had slightly stronger aggressiveness in P. ginseng. The analysis of partial sequences of the Histone H3 gene generated a high level of genetic diversity and geographic differentiation. A total of 132 variable sites were detected in 169 sequences, which formed 20 haplotypes with a haplotype diversity of 0.824. Genetic differentiation was positively correlated with geographic distance. The geographic populations in the range of Changbai Mountain were distinctly discriminated from those in other non-Changbai Mountain populations. No significant genetic differentiation was found between ginseng hosts. Cylindrocarpon-like fungi causing ginseng root diseases are geographically correlated in the genetic distance in Northeast China and should be managed correspondingly.

Anthracnose, caused by Colletotrichum species, is one of the most damaging fungal diseases affecting the cultivation of Polygonatum sibiricum , a traditional Chinese medicinal plant. To investigate the effects of Colletotrichum spaethianum infection on the growth and physiological metabolism of Polygonatum sibiricum , we conducted an experiment by root-irrigation the plants with the pathogen. The results indicated that after root treatment, the leaf margins of the plants were the first to show symptoms, beginning with chlorosis and the formation of yellow-brown lesions. These lesions then expanded, eventually leading to complete desiccation and easy detachment of the leaves. Following pathogen infection, there was a decrease in stomatal conductance, transpiration rate, and intercellular CO ₂ concentration in the leaves, yet the maximum photosynthetic efficiency was observed to increase. After infection, the chlorophyll content in leaves remained relatively stable, while the content of soluble protein decreased. The activity of superoxide dismutase (SOD), peroxidase (POD), and the content of malondialdehyde (MDA) all exhibited an initial increase followed by a decrease. Notably, the activity of SOD changed earlier than that of POD and MDA, suggesting that Polygonatum sibiricum has some capacity to resist Colletotrichum spaethianum . However, the growth indicators of Polygonatum sibiricum plants were largely unaffected by the Colletotrichum spaethianum stress. These findings contribute significantly to the understanding of the physiological changes in Polygonatum sibiricum following infection by Colletotrichum spaethianum and provide insights for disease diagnosis and control measures during Polygonatum sibiricum cultivation.

Cultivation culture is a precious wealth developed and inherited in the long-term agricultural activities of our country. The combination of cultivation culture and labor education into practice courses can effectively realize the cultivation of contemporary college students' labor spirit, make labor education more practical. In view of the problems existing in the teaching of practice courses of agriculture-related majors, taking the course of “Skills Practice in Vine Yard” as an example, this paper probes into the establishment of teaching objectives, the reform of course contents, teaching methods and examination methods, etc. Promote the cultivation of new agricultural talents through these measures.

Ilyonectria is a common soil-inhabiting fungal genus that comprises numerous plant phytopathogenic species capable of infecting a wide array of crops, medicinal herbs, and horticultural plants. However, the lack of a reliable and efficient genetic transformation method has severely hindered the elucidation of the pathogenic mechanisms of Ilyonectria pathogens. In this study, we established an efficient protoplast-mediated genetic transformation method for two dominant Panax root rot pathogens, I. robusta and I. vredehoekensis. Key parameters governing high-quality protoplast preparation, including mycelium culture time, enzyme composition, osmotic stabilizer type, digestion speed, and digestion time, were systematically optimized. Subsequently, orthogonal experiments were conducted to optimize the PEG-CaCl₂-mediated transformation conditions and to screen regeneration media for protoplasts. The optimal enzymatic system is composed of 20 mg/mL driselase and 10 mg/mL lysing enzyme, with 0.7 M NaCl as the osmotic stabilizer. Under these conditions, high-viability and high-quality protoplasts were obtained from I. vredehoekensis after 3 h of digestion at 150 rpm, and from I. robusta after 2 h of digestion at 100 rpm, yielding 5.52 × 10⁷ CFU/mL and 5.75 × 10⁷ CFU/mL protoplasts, respectively. Efficient transformation was achieved using a mannitol-prepared STC buffer mediated by 40% PEG4000. PCR and fluorescence microscopy verified positive transformants. Additionally, pathogenicity assays showed no significant differences in virulence between the transformed and wild-type strains, suggesting that the transformation procedure did not alter virulence. To the best of our knowledge, this is the first study to successfully establish genetic transformation methods for I. robusta and I. vredehoekensis, providing an essential technical platform for functional gene analysis, pathogenicity studies, and host–pathogen interaction research. In addition, the optimized transformation strategy may serve as a valuable reference for studies on other Ilyonectria species.