In October 2003, a new bacterial disease with symptoms similar to those caused by Xanthomonas axonopodis pv. poinsettiicola was observed on poinsettia leaves at a flower nursery in Zhejiang Province of China. Three Xanthomonas strains were isolated from infected plants and classified as X. axonopodis. They were differentiated from the pathotype strain LMG849 of X. axonopodis pv. poinsettiicola causing bacterial leaf spot of poinsettia by comparison of pathogenicity, substrate utilization and BOX-PCR genomic fingerprints.
Cell Differentiation ; China ; Euphorbia ; microbiology ; Plant Diseases ; microbiology ; Plant Leaves ; microbiology ; Species Specificity ; Xanthomonas ; classification ; genetics ; isolation & purification ; pathogenicity

Endophytic fungi were isolated from Macleaya cordata growing in Dabie Mountain by agar-block method, and then the endophytic fungi were grouped into different types based on their morphological characteristics, and thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) were employed to determine whether the metabolic substances contained sanguinarine or not, and then preliminarily identified by morphological method. The results showed that the leaves hosted the largest number of endophytes (96 isolates) followed by the stems (57 isolates) and finally the roots (28 isolates), respectively. Based on morphological characteristics the endophytic fungi were grouped into 26 types in our study. TLC and HPLC results showed that there was sanguinarine in the metabolic substances of BLH 51 strain. According to the morphological characteristic, the BLH 51 strain was identified as Fusarium proliferatum. All these indicated that the medicinal plant M. cordata harbors abundant endophytes, which could be a new source for the search of active secondary metabolites.
Benzophenanthridines ; metabolism ; Endophytes ; isolation & purification ; Fungi ; isolation & purification ; Isoquinolines ; metabolism ; Papaveraceae ; metabolism ; microbiology ; Plant Leaves ; microbiology ; Plant Roots ; microbiology ; Plant Stems ; microbiology

The paper is aimed at studying the diversity of endophytic fungi community from Paris polyphylla var. yunnanensis, and to provide a scientific basis for the utilization value of the endophytic fungi as bioactive material resources. In the present study, endophytic fungi were isolated from roots, rhizomes and leaves of wild P. polyphylla var. yunnanensis collected from Baoshan, Heqing county and Songming city of Yunnan province, and identified and classified by morphological methods together with its ITS sequence analysis. Seven and forty-nine strains of endophytic fungi were isolated from P. polyphylla var. yunnanensis. They were identified belonging to 41 genus. In these 41 genus, 3 genus exist in root only, 12 genus only exist in rhizome and 8 genus only exist in leaf. There was difference in endophytic fungi isolated from different sample sites. Endophytic fungi diversity from rhizomes of Heqing site was the highest. Endophytic fungi similarity coefficient was low among different sites and tissues. Based on these results, it is reasonable to propose that endophytic fungi of P. polyphylla var. yannanensis from different tissue and different sample sites has a certain difference which is possibly relate to their different habitats, different structure and composition of each tissue.
Biodiversity ; Endophytes ; classification ; genetics ; isolation & purification ; Fungi ; classification ; genetics ; isolation & purification ; Liliaceae ; microbiology ; Molecular Sequence Data ; Phylogeny ; Plant Leaves ; microbiology ; Plant Roots ; microbiology ; Plant Stems ; microbiology

Through investigation,it was found that the main disease of leaves was grey mold on Dendrobium officinale in Hubei province,which has a great impact on the yield and quality of D. officinale. The identification of morphological and molecular biological was used to prove that the pathogen was Botrytis cinerea. Through test the effect of 5 plant source fungicides and 4 antibiotic fungicides on mycelial growth of strain HS1,which proved 0. 3% eugenol had the best inhibitory effect,EC50 was 0. 29 mg·L^-1,the second was1% osthol and EC50 was 1. 12 mg·L^-1,the EC50 of 0. 5% matrine was 9. 16 mg·L^-1,the EC50 of the other six fungicides was higher than 10 mg·L^-1. The field control effect test proved that 0. 3% eugenol had the best control effect,reaching 89. 44%,secondly for 1%osthole,which was 77. 17%,0. 5% matrine was in the third place with 62. 37% of effective rate. However,the control effect of the other fungicides was less than 60%. The three plant-derived fungicides were safe for the produce of D. officinale and showed no phytotoxicity. The effect of these fungicides on the growth of D. candidum was tested,and proved that all the fungicides were safe and harmless to D. candidum. This study provides a research basis for the safe and effective prevention and control gray mold of D. officinale.
Alkaloids ; Botrytis/pathogenicity* ; Coumarins ; Dendrobium/microbiology* ; Eugenol ; Fungicides, Industrial ; Plant Diseases/prevention & control* ; Plant Leaves/microbiology* ; Quinolizines ; Matrines

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

Detecting plant health conditions plays a key role in farm pest management and crop protection. In this study, measurement of hyperspectral leaf reflectance in rice crop (Oryzasativa L.) was conducted on groups of healthy and infected leaves by the fungus Bipolaris oryzae (Helminthosporium oryzae Breda. de Hann) through the wavelength range from 350 to 2,500 nm. The percentage of leaf surface lesions was estimated and defined as the disease severity. Statistical methods like multiple stepwise regression, principal component analysis and partial least-square regression were utilized to calculate and estimate the disease severity of rice brown spot at the leaf level. Our results revealed that multiple stepwise linear regressions could efficiently estimate disease severity with three wavebands in seven steps. The root mean square errors (RMSEs) for training (n=210) and testing (n=53) dataset were 6.5% and 5.8%, respectively. Principal component analysis showed that the first principal component could explain approximately 80% of the variance of the original hyperspectral reflectance. The regression model with the first two principal components predicted a disease severity with RMSEs of 16.3% and 13.9% for the training and testing dataset, respectively. Partial least-square regression with seven extracted factors could most effectively predict disease severity compared with other statistical methods with RMSEs of 4.1% and 2.0% for the training and testing dataset, respectively. Our research demonstrates that it is feasible to estimate the disease severity of rice brown spot using hyperspectral reflectance data at the leaf level.
Data Interpretation, Statistical ; Least-Squares Analysis ; Oryza ; classification ; microbiology ; Plant Diseases ; classification ; microbiology ; Plant Leaves ; classification ; microbiology ; Principal Component Analysis ; Regression Analysis ; Severity of Illness Index ; Spectrum Analysis ; methods

Through potted inoculation test at room temperature and indoor analysis, the photosynthetic parameters and physiological and biochemical indexes of Paris polyphylla var. yunnanensis were observed after 28 arbuscular mycorrhizal (AM) fungi were injected into the P. polyphylla var. yunnanensis growing in a sterile soil environment. The results showed that AM fungi established a good symbiosis with P. polyphylla var. yunnanensis. The AM fungi influenced the photosynthetic parameters and physiological and biochemical indexes of P. polyphylla var. yunnanensis. And the influences were varied depending on different AM fungi. The application of AM fungi improved photosynthesis intensity of P. polyphylla var. yunnanensis mesophyll cells, the contents of soluble protein and soluble sugar, protective enzyme activity of P. polyphylla var. yunnanensis leaf, which was beneficial to resist the adverse environment and promote the growth of P. polyphylla var. yunnanensis. Otherwise, there was a certain mutual selectivity between P. polyphylla var. yunnanensis and AM fungi. From the comprehensive effect of inoculation, Racocetra coralloidea, Scutellospora calospora, Claroideoglomus claroideum, S. pellucida and Rhizophagus clarus were the most suitable AM fungi to P. polyphylla var. yunnanensis when P. polyphylla var. yunnanensis was planted in the field.
Fungi ; classification ; isolation & purification ; physiology ; Liliaceae ; metabolism ; microbiology ; Mycorrhizae ; classification ; isolation & purification ; physiology ; Photosynthesis ; Plant Leaves ; metabolism ; Rhizome ; microbiology

Calcium-dependent protein kinases (CDPKs) play an important regulatory role in the plantarbuscular mycorrhiza/rhizobium nodule symbiosis. However, the biological action of CDPKs in orchid mycorrhiza (OM) symbiosis remains unclear. In the present study, a CDPK encoding gene, designated as DoCPK1 (GenBank accession No. JX193703), was identified from D. officinale roots infected by an OM fungus-Mycena sp. using the reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) methods, for the first time. The full length cDNA of DoCPK1 was 2137 bp in length and encoded a 534 aa protein with a molecular weight of 59.61 kD and an isoelectric point (pI) of 6.03. The deduced DoCPK1 protein contained the conserved serine/threonine-protein kinase catalytic domain and four Ca2+ binding EF hand motifs. Multiple sequence alignment demonstrated that DoCPK1 was highly homologous (85%) to the Panax ginseng PgCPK1 (ACY78680), followed by CDPKs genes from wheat, rice, and Arabidopsis (ABD98803, ADM14342, Q9ZSA2, respectively). Phylogenetic analysis showed that DoCPK1 was closely related to CDPKs genes from monocots, such as wheat, maize and rice. Real time quantitative PCR (qPCR) analysis revealed that DoCPK1 was constitutively expressed in the included tissues and the transcript levels were in the order of roots > stems > seeds > leaves. Furthermore, DoCPK1 transcripts were significantly accumulated in roots 30 d after fungal infection, with 5.16 fold compared to that of the mock roots, indicating involvement of DoCPK1 during the early interaction between D. officinale and Mycena sp., and a possible role in the symbiosis process. This study firstly provided important clues of a CDPK gene associated with OM symbiosis, and will be useful for further functional determination of the gene involving in D. officinale and Mycena sp. symbiosis.
Agaricales ; growth & development ; physiology ; Amino Acid Sequence ; Base Sequence ; Cloning, Molecular ; DNA, Complementary ; genetics ; Dendrobium ; enzymology ; genetics ; microbiology ; Gene Expression Regulation, Plant ; Molecular Weight ; Mycorrhizae ; growth & development ; physiology ; Phylogeny ; Plant Leaves ; enzymology ; genetics ; microbiology ; Plant Roots ; enzymology ; genetics ; microbiology ; Plant Stems ; enzymology ; genetics ; microbiology ; Plants, Medicinal ; enzymology ; genetics ; microbiology ; Protein Kinases ; genetics ; metabolism ; Seeds ; enzymology ; genetics ; microbiology ; Sequence Alignment ; Symbiosis

Fallen leaves of Ficus altissima, F. virens, F. benjamina, F. fistulosa and F. semicordata, were collected in Chiang Mai Province in northern Thailand and examined for fungi. Eighty taxa were identified, comprising 56 anamorphic taxa, 23 ascomycetes and 1 basidiomycete. Common fungal species occurring on five host species with high frequency of occurrence were Beltraniella nilgirica, Lasiodiplodia theobromae, Ophioceras leptosporum, Periconia byssoides and Septonema harknessi. Colletotrichum and Stachybotrys were also common genera. The leaves of different Ficus species supported diverse fungal taxa, and the fungal assemblages on the different hosts showed varying overlap. The fungal diversity of saprobes at the host species level is discussed.
Ascomycota ; isolation & purification ; Basidiomycota ; isolation & purification ; Ecosystem ; Ficus ; microbiology ; Fungi ; classification ; isolation & purification ; Mitosporic Fungi ; isolation & purification ; Plant Leaves ; microbiology ; Species Specificity ; Thailand

OBJECTIVETo study the influence of arbuscular mycorrhizal fungi to Pinellia ternata leaf index, propagation coefficient, tuber yield and chemical composition.

METHODThe Pinellia ternata leaf length, width, plant height and leafstalk diameter were measured during growing time till P. ternata loded. The leaf index was calculated and the tuber yield were measured after harvest. The contents of guanosine was determined by HPLC method, and the alkaloid contents were determined by spectrophotometric method.

RESULT AND CONCLUSIONInoculated AM fungi could increase P. ternata propagation coefficient and the yield of tuber. Inoculated AM fungi could increase P. ternata leaf index, made leaf tends to be more like bamboo leaf type. Inoculated AM fungi could delayed P. ternata lodging time; G. mosseae + G. intraradices treatment (early inolulation time) proved better influence on increasing fresh weight and dry weight of P. ternata tuber and the propagation coefficient. Inoculated AM fungi could increase guanosine and alkaloid contents of Pinellia ternata tuber, and the contents of guanosine and alkaloid in inoculated treatments were higher than those in cultivated P. ternata from Hezhang; G. mosseae + G. intraradices treatment (later inolulation time) proved good effect on increasing the contents of guanosine and alkaloid.

Alkaloids ; chemistry ; Chromatography, High Pressure Liquid ; Guanosine ; chemistry ; Mycorrhizae ; growth & development ; physiology ; Pinellia ; chemistry ; growth & development ; microbiology ; Plant Leaves ; chemistry ; growth & development ; microbiology