OBJECTIVETo investigate diseases occurring in Rheum palmatum in Gansu province and identify pathogen.

METHODField survey in the main R. palmatum producing area and the pathogens were identified on the base of morphology.

RESULTEight fungal diseases have been found after disease surveys on R. palmatum in Gansu province from 2004 to 2007. They were leaf smut (Thecaphora schwarzmaniana), leaf spot (Septoria sp.), rust (Puccinia rheipalmati), ring spot (Ascochyta rhei), powdery mildew (Erysiphe polygoni.), grey mold (Botrytis sp.), root rot(Fusarium oxyxporium) and a virus disease.

CONCLUSIONLeaf smut, a severe disease with the incidence of 14%-26%, is the urgent problem waiting to be solved effectively. Powdery mildew and grey mold were reported for the first time in China.

Ascomycota ; pathogenicity ; Basidiomycota ; pathogenicity ; Botrytis ; pathogenicity ; China ; Fungi ; pathogenicity ; Fusarium ; pathogenicity ; Plant Diseases ; microbiology ; Rheum ; microbiology

Six diseases have been found after disease surveys on Notopterygium incisum in Gansu province during 2004 to 2007. They were brown spot (Ascochyta levistici), powdery mildew (Erysiphe heraclei), grey spot (Alternaria sp. ; Alternaria burnsii), leaf spot (Septoria dearnessii), angular leaf spot (Pleospora sp.), leaf streak (Phoma sp.), bacterial angular leaf spot and a virus disease. Bacterial angular leaf spot and powdery mildew are the urgent problems waiting to be solved effectively. All these diseases were reported for the first time in China.
Apiaceae ; microbiology ; virology ; Ascomycota ; isolation & purification ; pathogenicity ; Bacteria ; isolation & purification ; pathogenicity ; China ; Plant Diseases ; microbiology ; virology ; Viruses ; isolation & purification ; pathogenicity

In order to find new source of antifungal agents, eleven cultivable endophytic fungi were isolated from the roots,stems and leaves of Chelidonium majus by traditional method. Seven of them were identified as Colletotrichum(L1, L2, L3, S1, S3, S4, S5), and three of them were identified as Fusarium(R1,R2,R3) by morphological features and molecular biological technology. The antifungal activity test showed that all the tested fungi displayed some inhibitory activity against five common plant pathogens(C. gloeosporioides, Curvularia lunata, Pyricularia oryza, Alternaria alternate and A. brassicae), and their inhibition rate of some test items were over 60%. Among them, R1, S2, S3 and S4 were more potent than others. This study enriches the understanding of endophytes from Ch. majus and provides a basis for the study of new microbial fungicides.
Alternaria ; pathogenicity ; Antibiosis ; Ascomycota ; pathogenicity ; Chelidonium ; microbiology ; Colletotrichum ; chemistry ; isolation & purification ; Endophytes ; chemistry ; isolation & purification ; Fusarium ; chemistry ; isolation & purification

Ascomycota ; isolation & purification ; pathogenicity ; Female ; Humans ; Respiratory Hypersensitivity ; microbiology ; Sinusitis ; microbiology ; Young Adult

OBJECTIVETo control the medicinal plant diseases with the preparation of Trichoderma harzianum.

METHODAntagonistic action of the preparation to the pathogens of the medicinal plants in vitro, and controling effects of the preparation on these diseases in greenhouse and in the field were tested.

RESULTThe test in vitro showed that Trichoderma harzianum, used as a biocontrol factor, had stronger antagonistic action to Fusarium equiseti, Sclerotinia sp. and Rhizoctonia solani which were the medicinal plant pathogens of Astragalus membranaceus, Glehnia littoralis and Panax quinquefolium respectively. Biological controling effects on sclerotium root rot of Glehnia littoralis were 83.6% and 72.5% respectively in greenhouse and in the field with the preparation of Trichoderma harzianum. And controling effects on root rot of Astragalus membranaceus and seedling damping-off of Panax quinquefolium were 80% and 60% respectively in the field. The dosage of the preparation used in the field was 10 g.m-2.

CONCLUSIONThe preparation of Trichoderma harzianum can be used as a substitute for such chemicals as Carbendazim. Using the preparation to control medicinal plant diseases provides a technical safeguard for the good agricultural practice of medicinal plants.

Apiaceae ; growth & development ; microbiology ; Ascomycota ; pathogenicity ; Astragalus membranaceus ; growth & development ; microbiology ; Fusarium ; pathogenicity ; Panax ; growth & development ; microbiology ; Pest Control, Biological ; methods ; Plant Diseases ; microbiology ; Plant Roots ; microbiology ; Plants, Medicinal ; growth & development ; microbiology ; Rhizoctonia ; pathogenicity ; Soil Microbiology ; Trichoderma ; physiology

OBJECTIVETo screen the Trichodenna spp. for strong antagonist against ginseng root pathogens.

METHODThe biological characters of ten Trichoderma strains were compared by culturing on different media. And their antagonistic activity against Phytophthora cactorum, Cylindrocarpon destructans and Rhizoctonia solani were measured on PDA.

RESULT AND CONCLUSIONTv04-2 and Th3080 showed a good growth on soil solution medium and PDA, and also showed high inhibitory efficacy to the three pathogens. The two Trichoderma strains showed different growth rate under light conditions and pH. Trichoderma strains were sensitive to most fungicides used in ginseng root disease controlling, however Tv04-2 was not sensitive to the fungicide Junchong Jueba.

Ascomycota ; pathogenicity ; Hydrogen-Ion Concentration ; Light ; Panax ; microbiology ; Phytophthora ; pathogenicity ; Plant Diseases ; microbiology ; Plant Roots ; microbiology ; Plants, Medicinal ; microbiology ; Rhizoctonia ; pathogenicity ; Soil Microbiology ; Trichoderma ; growth & development ; isolation & purification ; physiology

A new stem rot disease is found to occur naturally on Arabidopsis plants in greenhouses of Fuzhou, China. In order to identify its pathogen, we conducted a series of fungal isolation and purification, plant reinoculation, and ascus and ascospore induction from the sclerotia. The isolate caused typical water-soaked lesions after reinoculation and produced sclerotia both on Arabidopsis plants and culture medium plates, and the sclerotia could be induced to produce discal apothecia and 8 binucleate ascospores per ascus. These disease symptom and fungal morphology data revealed that the fungus Sclerotinia sclerotiorum (Lib.) de Bary was the pathogen for Arabidopsis stem rot. To confirm this, we further amplified its large subunit ribosomal DNA (LSU rDNA) by polymerase chain reaction (PCR), and compared the sequence with the known LSU rDNA sequences in GenBank. The results show that the sequence shares the highest identities with the LSU rDNAs of different S. sclerotiorum strains. Taking all these data together, we concluded that the fungus that caused the Arabidopsis stem rot is S. sclerotiorum (Lib.) de Bary. This is the first report that Arabidopsis is naturally infected by S. sclerotiorum.
Arabidopsis ; microbiology ; Ascomycota ; classification ; genetics ; isolation & purification ; pathogenicity ; Base Sequence ; China ; DNA, Fungal ; genetics ; DNA, Ribosomal ; genetics ; Phylogeny ; Plant Diseases ; microbiology ; Plant Stems ; microbiology

OBJECTIVETo study the occurrence of Cercospora leaf spot of Lonicera macrathoides and fungicides control method, so as to provide scientific basis for its integrated pests management (IPM).

METHODThe field investigation and the field controlling trial were carried out for the research.

RESULTCercospora leaf spot was caused by C. rhamni. There was obvious relationship between the damage rate and the altitude, soil organic matter, available K, available P as well as variety. The controlling effect of 10% difenoconazole WG was the highest. 50% Thiram WP, 70% Mancozeb WP also had well controlling effect.

CONCLUSIONCercospora leaf spot of L. macrathoides could be controlled by suitability agricultural and chemical controls.

Ascomycota ; drug effects ; isolation & purification ; pathogenicity ; physiology ; Fungicides, Industrial ; pharmacology ; Lonicera ; microbiology ; Plant Diseases ; microbiology ; prevention & control ; Plant Leaves ; microbiology ; Virulence

OBJECTIVETo study difference among populations which belong to Astragalus membranaceus and A. membranaceus var. mongholicus on morphology, habit, characteristics of physiology and resistance to powdery mildew, and classify them in order to provide theoretical basis for breeding and improving varieties.

METHODMorphology, habits, isozyme and soluble protein electrophoretograms were compared among the populations. They were categorized by cluster analysis based on those electrophoretograms. Different ability of resistance to powdery mildew was also studied through comparing disease indices among six populations.

RESULTThe results showed A. membranaceus var. mongholicus was distinctly different from A. membranaceus. There was a special type in colonies of A. membranaceus, which showed hairy upper epidermis of leaflets and later florescence.

CONCLUSIONAstragalus for medicine could be categorized in three types A. membranaceus var. mongholicus, A. membranaceus early florescence type and A. membranaceus late florescence type. Among them A. membranaceus var. mongholicus is most resistant to powdery mildew, while A. membranaceus is easily infected, and the early florescence type is even more easily infected.

Ascomycota ; pathogenicity ; Astragalus Plant ; classification ; growth & development ; metabolism ; microbiology ; Astragalus membranaceus ; growth & development ; metabolism ; microbiology ; Peroxidase ; metabolism ; Phylogeny ; Plant Diseases ; microbiology ; Plant Proteins ; metabolism ; Plants, Medicinal ; classification ; growth & development ; metabolism ; microbiology

Peach brown rot, caused by Monilinia fructicola, is one of the most serious peach diseases. A strain belonging to the Actinomycetales, named Streptomyces blastmyceticus JZB130180, was found to have a strong inhibitory effect on M. fructicola in confrontation culture. Following the inoculation of peaches in vitro, it was revealed that the fermentation broth of S. blastmyceticus JZB130180 had a significant inhibitory effect on disease development by M. fructicola. The fermentation broth of S. blastmyceticus JZB130180 had an EC₅₀ (concentration for 50% of maximal effect) of 38.3 µg/mL against M. fructicola, as determined in an indoor toxicity test. Analysis of the physicochemical properties of the fermentation broth revealed that it was tolerant of acid and alkaline conditions, temperature, and ultraviolet radiation. In addition, chitinase, cellulase, and protease were also found to be secreted by the strain. The results of this study suggest that S. blastmyceticus JZB130180 may be used for the biocontrol of peach brown rot.
Ascomycota/pathogenicity* ; Bacterial Proteins/metabolism* ; Cell Wall/metabolism* ; Cellulase/metabolism* ; Chitinases/metabolism* ; Fermentation ; Fruit/microbiology* ; Pest Control, Biological/methods* ; Phylogeny ; Plant Diseases/prevention & control* ; Prunus persica/microbiology* ; Siderophores/metabolism* ; Streptomyces/physiology*