1.Biological characteristics of pathogen causing damping off on Aconitum kusnezoffiii and inhibitory effect of effective fungicides.
Si-Yi GUO ; Si-Yao ZHOU ; Tie-Lin WANG ; Ji-Peng CHEN ; Zi-Bo LI ; Ru-Jun ZHOU
China Journal of Chinese Materia Medica 2025;50(7):1727-1734
Aconitum kusnezoffii is a perennial herbaceous medicinal plant of the family Ranunculaceae, with unique medicinal value. Damping off is one of the most important seedling diseases affecting A. kusnezoffii, occurring widely and often causing large-scale seedling death in the field. To clarify the species of the pathogen causing damping off in A. kusnezoffii and to formulate an effective control strategy, this study conducted pathogen identification, research on biological characteristics, and evaluation of fungicide inhibitory activity. Through morphological characteristics, cultural traits, and phylogenetic tree analysis, the pathogen causing damping off in A. kusnezoffii was identified as Rhizoctonia solani, belonging to the AG5 anastomosis group. The optimal temperature for mycelial growth of the pathogen was 25-30 ℃, with OA medium as the most suitable medium, pH 8 as the optimal pH, and sucrose and yeast as the best carbon and nitrogen sources, respectively. The effect of light on mycelial growth was not significant. In evaluating the inhibitory activity of 45 chemical fungicides, including 30% hymexazol, and 4 biogenic fungicides, including 0.3% eugenol, it was found that 30% thifluzamide and 50% fludioxonil had significantly better inhibitory effects on R. solani than other tested agents, with EC_(50) values of 0.129 6,0.220 6 μg·mL~(-1), respectively. Among the biogenic fungicides, 0.3% eugenol also showed an ideal inhibitory effect on the pathogen, with an EC_(50) of 1.668 9 μg·mL~(-1). To prevent the development of resistance in the pathogen and to reduce the use of chemical fungicides, it is recommended that the three fungicides above be used in rotation during production. These findings provide a theoretical basis for the accurate diagnosis and effective control strategy for R. solani causing damping off in A. kusnezoffii.
Fungicides, Industrial/pharmacology*
;
Plant Diseases/microbiology*
;
Rhizoctonia/growth & development*
;
Aconitum/microbiology*
;
Phylogeny
;
Mycelium/growth & development*
2.Progress of research on potato scab and its prevention and control.
Yue MA ; Xiu WANG ; Naiqin ZHONG ; Pan ZHAO ; Jiahe WU
Chinese Journal of Biotechnology 2025;41(10):3651-3666
In recent years, potato scab caused by pathogenic Streptomyces spp. has become widespread globally, with increasing damage severely compromising the commercial value and storability of tubers. The pathogens are transmitted through the soil and seeds of potato, while existing control technologies have demonstrated limited efficacy in preventing the colonization and spread of pathogens, which pose a critical bottleneck in the sustainable development of the potato industry. This study systematically examines the pathogen characteristics and pathogenic mechanisms, evaluates the impacts of soil nutrients and microbial community structure on disease severity, and analyzes limitations in current chemical control, biological control, and disease-resistant variety breeding approaches. We propose an integrated control strategy of disease-resistant varieties, phosphorus fertilizer reduction, fertilizer efficiency enhancement, and phosphorus-soluble antagonistic fungicides, aiming to provide novel research perspectives for achieving effective prevention and control of potato scab.
Solanum tuberosum/microbiology*
;
Plant Diseases/prevention & control*
;
Streptomyces/pathogenicity*
;
Disease Resistance
;
Fungicides, Industrial/pharmacology*
;
Fertilizers
;
Soil Microbiology
3.Screening of soil biocontrol bacteria and evaluation of their control effects on Fusarium head blight of wheat.
Dongfang WANG ; Xinxin ZHAI ; Chunlin YANG ; Huilan ZHANG ; Jie WU ; Zerong SONG ; Pan ZHAO ; Yu CHI
Chinese Journal of Biotechnology 2025;41(10):3764-3773
Fusarium head blight (FHB), caused by Fusarium graminearum, not only leads to severe yield losses but also poses a threat to food safety due to the mycotoxins produced by the pathogen. Since this disease is preventable but not curable, the current control mainly relies on chemical fungicides, the long-term use of which may lead to pathogen resistance and environmental pollution. To develop green control methods, we screened 13 biocontrol strains from the rhizosphere soil of wheat, among which strain No. 12 (identified as Pythium aphanidermatum) showed significant antifungal effects. In the plate confrontation test, this strain reduced the colony diameter of the pathogen by 69.2% (1.47 mm vs. 4.78 mm in the control group), with an inhibition rate of 77% (P < 0.01). Microscopic observation revealed obvious deformations in the pathogen hyphae, suggesting a lysing effect. The coleoptile experiment further confirmed that the pre-treatment with this strain reduced the incidence rate to 0. These findings provide new candidate strains for the biocontrol of FHB and offer a scientific basis for reducing the use of chemical fungicides and promoting sustainable agricultural development.
Triticum/growth & development*
;
Fusarium/growth & development*
;
Plant Diseases/prevention & control*
;
Soil Microbiology
;
Pest Control, Biological/methods*
;
Pythium/physiology*
;
Biological Control Agents
;
Rhizosphere
;
Fungicides, Industrial
4.Sensitivity baseline establishment and resistance risk assessment of Botrytis cinerea from Panax ginseng to prochloraz.
Mo-Yi YUE ; Rong WANG ; Yong LI ; Yan-Min LIU ; Wan-Long DING
China Journal of Chinese Materia Medica 2023;48(3):636-641
This study aimed to establish the baseline sensitivity of Botrytis cinerea from Panax ginseng to prochloraz, and ensure the fitness of prochloraz-resistant mutants and the cross-resistance of B. cinerea to prochloraz and commonly used fungicides for the prevention and control of gray mold including boscalid, pyraclostrobin, iprodione, and pyrimethanil. The sensitivity of B. cinerea from P. ginseng to fungicides was determined by the mycelial growth rate method. The prochloraz-resistant mutants were screened out through fungicide domestication and ultraviolet(UV) induction. The fitness of resistant mutants was determined through the stability of subculture, mycelial growth rate, and pathogenicity test. The cross-resistance between prochloraz and the four fungicides was determined by Person correlation analysis. The results showed that all B. cinerea strains tested were sensitive to prochloraz, and the EC_(50) value ranged from 0.004 8 to 0.062 9 μg·mL~(-1), with an average of 0.022 μg·mL~(-1). The sensitivity frequency distribution diagram showed that 89 B. cinerea strains were located within the main peak with a continuous single peak curve, and the average EC_(50) value of 0.018 μg·mL~(-1) was taken as the baseline sensitivity of B. cinerea to prochloraz. The fungicide domestication and UV induction obtained 6 resistant mutants, among which 2 strains were unstable and the other 2 strains showed decreased resistance after multiple generations of culture. Furthermore, the mycelial growth rate and spore yield of all resistant mutants were lower than those of their parents, and the pathogenicity of most mutants was lower than that of their parents. In addition, prochloraz had no obvious cross-resistance with boscalid, pyraclostrobin, iprodione, and pyrimethanil. In conclusion, prochloraz has great potential for controlling gray mold in P. ginseng, and the resistance risk of B. cinerea to prochloraz is low.
Humans
;
Panax
;
Fungicides, Industrial
5.Identification, biological characterization, and fungicide screening of pathogens causing leaf spot of Belamcanda chinensis.
Ya-Wen YANG ; Qiao-Huan CHEN ; Jia ZHOU ; Bi-Sheng HUANG ; Yu-Huan MIAO ; Da-Hui LIU
China Journal of Chinese Materia Medica 2022;47(22):6042-6049
The leaf spot of Belamcanda chinensis often appears in May to June and spreads rapidly during the flowering stage(July to September) in the cultivation fields, seriously affecting the yield and quality of B. chinensis. To identify and characterize the pathogens of the leaf spot, we isolated two species of Alternaria, identified them according to Koch's postulates, and tested their pathogenicity and biological characteristics. Furthermore, we determined the inhibitory effects of 6 chemical fungicides, 1 plant fungicide, and 3 microbial fungicides on the pathogens by using mycelial growth rate and plate confrontation method to select the appropriate control agents. The results showed that the two pathogens causing B. chinensis leaf spot were Alternaria tenuissima and A. alternata. The conidia of A. tenuissima often formed long chains with no or a few branches, while those of A. alternata often formed short branched chains. The optimum growth temperature of both A. tenuissima and A. alternata was 25 ℃. The two pathogens grew well in alkaline environment. The indoor fungicide screening experiments showed that 40% flusilazole had good inhibitory effects on the two pathogens, with the EC_(50) values of 12.42 mg·L~(-1) and 12.78 mg·L~(-1) for A. tenuissima and A. alternata, respectively. The results of this study provide a theoretical basis for the subsequent theoretical research and field control of B. chinensis leaf spot.
Fungicides, Industrial/pharmacology*
;
Research
;
Iris Plant
;
Spores, Fungal
;
Mycelium
6.Identification, biological characteristics, and control of pathogen causing southern blight of Pinellia ternata.
Jia ZHOU ; Qiao-Huan CHEN ; Jia-Wei XU ; Hong CHEN ; Bi-Sheng HUANG ; Yu-Huan MIAO ; Da-Hui LIU
China Journal of Chinese Materia Medica 2022;47(19):5209-5216
In summer in 2020, Pinellia ternata in many planting areas in Hubei suffered from serious southern blight, as manifested by the yellowing and wilted leaves and rotten tubers. This study aims to identify the pathogen, clarify the biological characteristics of the pathogen, and screen fungicides. To be specific, the pathogen was isolated, purified, and identified, and the pathogenicity was detected according to the Koch's postulates. Moreover, the biological characteristics of the pathogen were analyzed. Furthermore, PDA plates and seedlings were used to determine the most effective fungicides. The results showed that the mycelia of the pathogen were white and villous with silk luster, which produced a large number of white to black brown sclerotia. The pathogen was identified as Athelia rolfsii by morphological observation and molecular identification based on LSU and TEF gene sequences. The optimum growth conditions for A. rolfsii were 30 ℃ and pH 5-8, and the optimum conditions for the germination of sclerotia were 25 ℃ and pH 7-9. Bacillus subtilis, difenoconazole, and flusilazole were identified as effective fungicides with PDA, and their half maximal effective concentration(EC_(50)) was all less than 5 mg·L~(-1). The effective fungicides screened with the seedlings were hymexazol and difenoconazole. Based on the screening experiments, difenoconazole can be used as the main agent for the prevention and treatment of southern blight.
Pinellia/genetics*
;
Fungicides, Industrial/pharmacology*
;
Seedlings
;
Bacillus subtilis
;
Mycelium
7.Identification, biological characteristics, and fungicide screening of pathogen of black spot in Aconitum carmichaelii.
Jia ZHOU ; Tie-Lin WANG ; Yu-Huan MIAO ; Da-Hui LIU
China Journal of Chinese Materia Medica 2022;47(5):1215-1221
In Hezhang county, Guizhou province, black spot tends to occur to Aconitum carmichaelii in the hot rainy summer, with the incidence up to 50%-70%, seriously impacting the yield and quality of the medicinal material. Thus, this study aims to clarify the pathogen and the occurrence characteristics. To be specific, the pathogen was isolated and identified according to Koch's postulates and the pathogenicity and biological characteristics were determined. In addition, the sensitivity of the pathogen to four microbial fungicides, four botanical fungicides, and five chemical fungicides was determined with the mycelium growth rate method for the purpose of screening out optimal fungicides. The pathogen was identified as Alternaria alternate, as evidenced by the similar colony morphology and microscopic characteristics and 99.55%-100% similarity in sequences of rDNA-ITS, LSU, 18S, and TEF of the two. The optimum growth conditions for A. alternata were 28 ℃, pH 8, and continuous darkness. Bacillus subtilis had strong inhibitory effect on the pathogen, and the inhibition rate was more than 90% when the concentration was 1 mg·L~(-1). In addition, difenoconazole and quinoline copper can also control the pathogen, with median effective concentration(EC_(50)) of 2.92 and 9.02 mg·L~(-1), respectively. This study lays a theoretical basis for the field control of black spot in A. carmichaelii.
Aconitum
;
Alternaria
;
Fungicides, Industrial/pharmacology*
;
Mycelium
8.Identification,biological characteristics and fungicide screening of pathogen of southern blight in Cynanchum stauntonii.
Jin-Xin LI ; Qiao-Huan CHEN ; Yu-Huan MIAO ; Tie-Lin WANG ; Da-Hui LIU
China Journal of Chinese Materia Medica 2021;46(13):3303-3310
During the high-temperature and rainy season from June to October in 2017-2019,serious southern blight broke out in the Cynanchum stauntonii planting area in Tuanfeng county,Hubei province,which had a great impact on the yield and quality of medicinal materials. In this study,the pathogen of C. stauntonii was isolated,purified,and identified,and the pathogenicity was tested according to Koch's postulates. Meanwhile,the biological characteristics of the pathogen were analyzed. On this basis,the effective fungicides were screened in laboratory. Finally,the pathogen( BQ-1) was identified as Athelia rolfsii( Deuteromycotina,Basidiomycota,anamorph: Sclerotium rolfsii). The optimum growth conditions for BQ-1 were 25-30 ℃,p H 5-8,and alternating light and dark.The effective chemical fungicides were lime-sulphur-synthelic-solution( LSSS) and flusilazole,and the effective botanical fungicide was osthole. BQ-1 was highly homologous to the pathogen HS-1 of peanut southern blight,with the similarity of 18 S r DNA and TEF sequences at 99. 09%. The southern blight in C. stauntonii might be resulted from that in peanut. In the production of C. stauntonii,the following measures should be taken: avoiding rotation or neighboring with peanut,draining water from June to October to reduce humidity,and reasonably applying fungicides.
Basidiomycota
;
Cynanchum
;
Fungicides, Industrial/pharmacology*
;
Humidity
9.Effect of different fungicides on efficiency of mycorrhizal symbiosis on Salvia miltiorrhiza.
Chun-Juan PU ; Peng-Ying LI ; Yu-Zhi LUO ; Xiu-Teng ZHOU ; Ai-Juan SHAO ; Mei-Lan CHEN
China Journal of Chinese Materia Medica 2021;46(6):1368-1373
Arbuscular mycorrhizal fungi provided is beneficial to Salvia miltiorrhiza for increasing yield, promoting the accumulation of active ingredients, and alleviating S. miltiorrhiza disease etc. However, the application of fungicides will affect the benefit of arbuscular mycorrhizal fungi and there is little research about it. This article study the effect of four different fungicides: carbendazim, polyoxin, methyl mopazine, and mancozeb on mycorrhiza benefit to S. miltiorrhiza by the infection intensity of arbuscular mycorrhizal fungi, the growth of S. miltiorrhiza, and the content of active ingredients. RESULTS:: showed that different fungicides had different effects. The application of mancozeb had the strongest inhibitory effect on the mycorrhizal benefit to S. miltiorrhiza. Mancozeb significantly reduced the mycorrhizal colonization and the beneficial effect of arbuscular mycorrhizal fungi on the growth and the accumulation of active components of S. miltiorrhiza. The application of polyoxin had no significant effect on mycorrhizal colonization. Instead, it had a synergistic effect with the mycorrhizal benefit to promoting the growth and accumulation of rosmarinic acid of S. miltiorrhiza. The inhibitory strengths of four fungicides are: mancozeb>thiophanate methyl, carbendazim>polyoxin. Therefore, we recommend applying biological fungicides polyoxin and avoid applying chemical fungicides mancozeb for disease control during mycorrhizal cultivation of S. miltiorrhiza.
Fungicides, Industrial/pharmacology*
;
Mycorrhizae
;
Plant Roots
;
Salvia miltiorrhiza
;
Symbiosis
10.Efficacy of Essential Trace Elements Supplementation on Mineral Composition, Sperm Characteristics, Antioxidant Status, and Genotoxicity in Testis of Tebuconazole-treated Rats.
Hajer BEN SAAD ; Fatma BEN ABDALLAH ; Intidhar BKHAIRIA ; Ons BOUDAWARA ; Moncef NASRI ; Ahmed HAKIM ; Ibtissem BEN AMARA
Biomedical and Environmental Sciences 2020;33(10):760-770
Objective:
This research was performed to evaluate the effect of tebuconazole (TBZ) on reproductive organs of male rats and to assess the protective role of combined essential trace elements in alleviating the detrimental effect of TBZ on male reproductive function.
Methods:
For this purpose, 48 rats were exposed to 100 mg/kg TBZ, TBZ supplemented with zinc (Zn), selenium (Se), copper (Cu), and iron (Fe), TBZ + (Se + Zn); TBZ + Cu; or TBZ + Fe. The experiment was conducted for 30 consecutive days.
Results:
TBZ caused a significant perturbation in mineral levels and reduction in reproductive organs weights, plasma testosterone level, and testicular antioxidant enzyme activities. The TBZ-treated group also showed a significant increase in sperm abnormalities (count, motility, and viability percent), plasma follicle-stimulating hormone and luteinizing hormone concentrations, lipid peroxidation, protein oxidation, and severe DNA degradation in comparison with the controls. Histopathologically, TBZ caused testis impairments. Conversely, treatment with trace elements, in combination or alone, improved the reproductive organ weights, sperm characteristics, TBZ-induced toxicity, and histopathological modifications in testis.
Conclusion
TBZ exerts significant harmful effects on male reproductive system. The concurrent administration of trace elements reduces testis dysfunction, fertility, and toxicity induced by TBZ.
Animal Feed/analysis*
;
Animals
;
Antioxidants/metabolism*
;
Diet
;
Dietary Supplements/analysis*
;
Fungicides, Industrial/adverse effects*
;
Male
;
Minerals/metabolism*
;
Mutagenicity Tests
;
Rats
;
Rats, Wistar
;
Spermatozoa/physiology*
;
Testis/physiology*
;
Trace Elements/metabolism*
;
Triazoles/adverse effects*

Result Analysis
Print
Save
E-mail